Photothermal nanoblade for patterned cell membrane cutting.

We report a photothermal nanoblade that utilizes a metallic nanostructure to harvest short laser pulse energy and convert it into a highly localized and specifically shaped explosive vapor bubble. Rapid bubble expansion and collapse punctures a lightly-contacting cell membrane via high-speed fluidic flows and induced transient shear stress. The membrane cutting pattern is controlled by the metallic nanostructure configuration, laser pulse polarization, and energy. Highly controllable, sub-micron sized circular hole pairs to half moon-like, or cat-door shaped, membrane cuts were realized in glutaraldehyde treated HeLa cells

Image patterned molecular delivery into live cells using gold particle coated substrates.

An image-patterned molecular delivery system for mammalian cells is demonstrated by pulsed laser irradiation of gold particles immobilized on a substrate below a cell monolayer. Patterned cavitation bubble nucleation was captured using a time-resolved imaging system and molecular delivery verified by observing the uptake of a membrane-impermeable fluorescent dye, calcein. Delivery efficiency as high as 90% was observed and multiplexed, patterned dye delivery was demonstrated

Subvacuum effects of the quantum field on the dynamics of a test particle

We study the effects of the electromagnetic subvacuum fluctuations on the dynamics of a nonrelativistic charged particle in a wavepacket. The influence from the quantum field is expected to give an additional effect to the velocity uncertainty of the particle. In the case of a static wavepacket, the observed velocity dispersion is smaller in the electromagnetic squeezed vacuum background than in the normal vacuum background. This leads to the subvacuum effect. The extent of reduction in velocity dispersion associated with this subvacuum effect is further studied by introducing a switching function. It is shown that the slow switching process may make this subvacuum effect insignificant. We also point out that when the center of the wavepacket undergoes non-inertial motion, reduction in the velocity dispersion becomes less effective with its evolution, no matter how we manipulate the nonstationary quantum noise via the choice of the squeeze parameters. The role of the underlying fluctuation-dissipation relation is discussed.Comment: 30 pages, 2 figure

Graptopetalum paraguayense

Role of inflammation-induced oxidative stress in the pathogenesis and progression of chronic inflammatory airways diseases has received increasing attention in recent years. Nuclear factor erythroid 2-related factor 2 is the primary transcription factor that regulates the expression of antioxidant and detoxifying enzymes. Graptopetalum paraguayense E. Walther, a vegetable consumed in Taiwan, has been used in folk medicine for protection against liver injury through elevating antioxidation. Recently, we found that gallic acid is an active compound of Graptopetalum paraguayense E. Walther, which has been reported to inhibit T-helper 2 cytokines. Currently, we assumed that Graptopetalum paraguayense E. Walther may potentially protect against ovalbumin-induced allergy and airway inflammation. Results demonstrated that Graptopetalum paraguayense E. Walther ethanolic extracts (GPE) clearly inhibited airway inflammation, mucus cell hyperplasia, and eosinophilia in OVA-challenged mice. Additionally, GPE also prevented T-cell infiltration and Th2 cytokines, including interleukin- (IL-)4, IL-5, and IL-13 generations in bronchial alveolar lavage fluid. The adhesion molecules ICAM-1 and VCAM-1 were substantially reduced by GPE treatment mediated by Nrf2 activation. Moreover, GPE attenuated GATA3 expression and inhibited Th2 signals of the T cells. These findings suggested that GPE ameliorated the development of airway inflammation through immune regulation

SEISMIC ANALYSIS OF WATER SUPPLY SYSTEMS BY EARTHQUAKE SCENARIO SIMULATION

In the past decade, scenario simulation has played a more and more important role in urban earthquake hazard mitigation and emergency response. Both public and private sectors can be enhanced in terms of their seismic preparedness and operation if adequate implementation of seismic scenario simulation can be employed. Regarding water utilities, system-wide retrofit and emergency planning can be conducted to reduce the likely damage and losses prior to the occurrence of a devastating earthquake. Post-earthquake repair personnel and material dispatching, temporary water supply for affected people, emergency water supply for hospitals and fire fighting, strategies for restoration and recovery can all benefit from scenario-based analyses. In this research work, efforts were made to study and integrate pivotal technologies essential to the earthquake damage and serviceability analysis of water systems, such as seismic hazard analysis, empirical formulae for pipe repair rates, hydraulic analysis of water network system in terms of pressurized pipe flow simulation, hydraulic models for various types of pipe damages, and Monte Carlo method for the performance analysis of large and complicated systems. The water system in Yi-lan County, Taiwan was selected as a test bed for the demonstration of its seismic serviceability analysis under an M7.1 earthquake scenario