Axisymmetric polydimethysiloxane microchannels for in vitro hemodynamic studies

The current microdevices used for biomedical research are often manufactured using microelectromechanical systems (MEMS) technology. Although it is possible to fabricate precise and reproducible rectangular microchannels using soft lithography techniques, this kind of geometry may not reflect the actual physiology of the microcirculation. Here, we present a simple method to fabricate circular polydimethysiloxane (PDMS) microchannels aiming to mimic an in vivo microvascular environment and suitable for state-of-the-art microscale flow visualization techniques, such as confocal µPIV/PTV. By using a confocal µPTV system individual red blood cells (RBCs) were successfully tracked trough a 75 µm circular PDMS microchannel. The results show that RBC lateral dispersion increases with the volume fraction of RBCs in the solution, i.e. with the hematocrit

Intravascular stent motor powered by ultrasonic irradiation

We have developed a stent motor that can move in the blood vessel by applying the technique of the ultrasonic motor. First, we have designed a horn to provide ultrasonic energy to the stent from outside of human body. Second, we have also designed a stent motor that consists of two parts; a stator and receivers. The receiver unit obtains the ultrasonic wave from outside. The stator is the coil shape and it can move smoothly in intravascular. Finally, we have made experiments by the horn and stent motor. We have succeeded in driving the stent motor back and forth in the water

Present status and future outlook of plant factories in Japan

Plant factories for the steady production of high-quality vegetables year round, and which can be divided into solar and artificial-light types, have recently been expanding in Japan as trigged by a report by a collaboration study group in 2009 and the Great East Japan Earthquake in 2011. Common solar-type plant factories with mulch-span roofs are often difficult to construct in the northern areas of Japan, especially along the Japan Sea coast, because of limited sunshine duration and heavy winter snowfall, while artificial light-type factories are more promising in this region although high running costs due to electricity bills for irradiating plants and cooling the room often hinder the promotion of such facilities. The use of LEDs has recently increased in artificial light-type plant factories, but fluorescent lights are still predominant for economic reasons. Generally only small plants can be grown commercially in artificial light-type factories and the light intensity reaching the lower leaves decreases continuously as the stem of the plant elongates, deteriorating light use efficiency. Flexible organic electroluminescent devices able to cover the whole plant when irradiation is required and that can easily be applied/removed like a plastic film are expected to be introduced in both types of plant factories

Theory of radiation trapping by the accelerating solitons in optical fibers

We present a theory describing trapping of the normally dispersive radiation by the Raman solitons in optical fibers. Frequency of the radiation component is continuously blue shifting, while the soliton is red shifting. Underlying physics of the trapping effect is in the existence of the inertial gravity-like force acting on light in the accelerating frame of reference. We present analytical calculations of the rate of the opposing frequency shifts of the soliton and trapped radiation and find it to be greater than the rate of the red shift of the bare Raman soliton. Our findings are essential for understanding of the continuous shift of the high frequency edge of the supercontinuum spectra generated in photonic crystal fibers towards higher frequencies.Comment: Several misprints in text and formulas corrected. 10 pages, 9 figures, submitted to Phys. Rev.

Looking at a soliton through the prism of optical supercontinuum

A traditional view on solitons in optical fibers as robust particle-like structures suited for informa- tion transmission has been significantly altered and broadened over the past decade, when solitons have been found to play the major role in generation of octave broad supercontinuum spectra in photonic-crystal and other types of optical fibers. This remarkable spectral broadening is achieved through complex processes of dispersive radiation being scattered from, emitted and transformed by solitons. Thus solitons have emerged as the major players in nonlinear frequency conversion in optical fibers. Unexpected analogies of these processes have been found with dynamics of ultracold atoms and ocean waves. This colloquium focuses on recent understanding and new insights into physics of soliton-radiation interaction and supercontinuum generation.Comment: http://rmp.aps.org/abstract/RMP/v82/i2/p1287_1 (some figures have been deleted due to space limits imposed by archive

Effects of goshajinkigan (Niu-Che-Sen-Qi-Wan) for resiniferatoxin-sensitive afferents on detrusor overactivity induced by acetic acid in conscious rats

Electronic version of an article published as [AMERICAN JOURNAL OF CHINESE MEDICINE, 34, 2, 2006, 285-293] [doi:10.1142/S0192415X06003837] © [copyright World Scientific Publishing Company] [http://www.worldscinet.com/ajcm/ajcm.shtml]ArticleAmerican Journal of Chinese Medicine. 34(2): 285-293 (2006)journal articl