Study on Heat Transfer and Flow Characteristic Under Phase-Change Process of an Acoustically Levitated Droplet

Acoustic levitation is one of the levitation technique which is expected to be used for analytical chemistry and manufacturing new materials. Thus, it is important to gather the knowledge about acoustically levitated droplet. The purpose of this study is to investigate the heat transfer and flow behavior under phase change process of an acoustically levitated droplet. The following results were obtained from experiments. Evaporation process and external flow structure of the levitated droplet is visualized by a high speed camera and it is found that they differ by the type of fluid. Toroidal vortices are observed near the surface of the ethanol solution droplet. Heat transfer coefficient is estimated from the volume change and temperature gradient. It is substantially higher than that estimated by the existing experimental correlation.     

Semiautomatic leakage analyzing system for time series fluorescein ocular fundus angiography

An algorithm for measuring an index of leakage in fluorescein fundus angiography is presented. The number of pixels whose gray level exceeds an automatically determined slice level is calculated. An automatic blood vessel elimination technique is introduced. Further, a method of measuring the short term change of leakage from a time series of the fluorescein fundus angiographs is described. Our system can also deal with the time series images obtained on different occasions (long term change).The features of this paper are: (1) this paper deals with double time sequence images (short and long term); (2) an automatic blood vessel recognition algorithm is employed.     

Apoptotic proteins Reaper and Grim induce stable inactivation in voltage-gated K+ channels

Drosophila genes reaper, grim, and head-involution-defective (hid) induce apoptosis in several cellular contexts. N-terminal sequences of these proteins are highly conserved and are similar to N-terminal inactivation domains of voltage-gated potassium (K+) channels. Synthetic Reaper and Grim N terminus peptides induced fast inactivation of Shaker-type K+ channels when applied to the cytoplasmic side of the channel that was qualitatively similar to the inactivation produced by other K+ channel inactivation particles. Mutations that reduce the apoptotic activity of Reaper also reduced the synthetic peptide's ability to induce channel inactivation, indicating that K+ channel inactivation correlated with apoptotic activity. Coexpression of Reaper RNA or direct injection of full length Reaper protein caused near irreversible block of the K+ channels. These results suggest that Reaper and Grim may participate in initiating apoptosis by stably blocking K+ channels.     

Effects of protease inhibitors on binding of sperm to the vitelline coat of ascidian eggs: implications for participation of a proteasome (multicatalytic proteinase complex)

The relation between left-ventricular stroke volume (SV) and end-diastolic volume (EDV) was determined based on angiocardiographic measurements in 10 open-chest minipigs under varying filling conditions (blood letting or infusions). The results were compared with a theoretical relation calculated under the assumption of varying EDV but constancy of myocardial properties. In contrast to the linear increase of SV as a function of EDV as found in the animal experiments, the calculated curve reveals a maximum near the normal operating point with a decrease in the range of higher EDV. It can be concluded that the well-known increase of SV with increasing ventricular filling, beyond the normal EDV, is almost completely due to muscle physiological factors (mainly increase in Ca2+ sensitivity of the contractile apparatus), whereas the decrease of SV in the range of low filling pressure is mainly due to the geometrical conditions.     

Surface temperature of Pd/C catalyst under microwave irradiation in dechlorination process of PCBs

In recent years, a new effective method of processing for polychlorinated biphenyls (PCBs) has been developed: It enables PCBs to become harmless by dechlorinating them using a 2.45 GHz microwave (MW). Compared with conventional thermal heating, MW processing hardly produces any harmful byproduct materials, and has high reaction velocity. To investigate such promotion of chemical reaction by MW irradiation, the surface temperature of the catalyst is measured by an infrared camera just after the irradiation by MW. It is recognized that there are some heated regions on the catalyst and the temperature is not uniform. It is natural to say that chemical reaction is promoted well on such a heated region. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Dielectrics loss of PCBs leading to microwave heating

A new effective processing for polychlorinated biphenyls (PCBs) has been recently developed. PCBs become harmless by dechlorination using 2.45 GHz-microwave (MW). To investigate such chemical reaction by MW irradiation, the dielectric loss of pure PCBs solutions and an isomer mixture in MW band is measured. Some PCBs and isopropyl alchol, added as a source of hydrogen supply have high dielectric loss in MW band. This suggests that MW heats PCBs and isopropyl alchol, and then the temperature of the solvent consisting mainly of insulating oil rises by the thermal conduction. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.