Extinguishment of diffusion flames formed over a porous plate burner using rubber balloons filled with inert gases

We have proposed an inert gas, rubber-balloon extinguishing method which might increase the effectiveness of extinguishing flames and decreasing the amounts of agents needed for fire suppression. Hence, extinguishing experiments have been performed to further clarify possible extinguishing characteristics, mechanisms and scaling effects of this method. Carbon dioxide, nitrogen, argon and helium gases were used as the extinguishing agents. Methane-air and propane-air diffusion flames were formed on two different diameter, round porous plate burner and used as the targets for extinguishment. The extinguishing probabilities were measured, and the extinguishing processes were observed with a high-speed camera. As a result, an effectiveness ranking of an inert gas in the rubber-balloon extinguishing method was in agreement with that of a cup-burner method. Moreover, determinations of extinguishing limits were accomplished, defined as the minimum volume of the inert gas required for successful extinguishment of flames; these limits depended on the balance of the heat loss caused by an inert gas and the heat production within the flame, and also on the forming process of a flammable premixing layer near the surface of the burner. In addition, all the extinguishing limits were represented by a unique, constant relationship depending on the non-dimensional number of the ratio of the heat absorbing rate of the inert gas to the heat release rate of the flame multiplied by the Schmidt number of the fuel species

Regional Inequality Simulations Based on Asset Exchange Models with Exchange Range and Local Support Bias

To gain insights into the problem of regional inequality, we proposed new regional asset exchange models based on existing kinetic income-exchange models in economic physics. We did this by setting the spatial exchange range and adding bias to asset fraction probability in equivalent exchanges. Simulations of asset distribution and Gini coefficients showed that suppressing regional inequality requires, firstly an increase in the intra-regional economic circulation rate, and secondly the narrowing down of the exchange range (inter-regional economic zone). However, avoiding over-concentration of assets due to repeat exchanges requires adding a third measure; the local support bias (distribution norm). A comprehensive solution incorporating these three measures enabled shifting the asset distribution from over-concentration to exponential distribution and eventually approaching the normal distribution, reducing the Gini coefficient further. Going forward, we will expand these models by setting production capacity based on assets, path dependency on two-dimensional space, bias according to disparity, and verify measures to reduce regional inequality in actual communities.Comment: 14 pages, 8 figures. Published online at http://redfame.com/journal/index.php/aef/article/view/494

Immunohistochemical analysis of P-glycoprotein expression in diverse histological types of epithelial ovarian tumors.

P-glycoprotein is a transmembrane protein which acts as an energy-dependent drug efflux pump for a variety of anti-cancer drugs. The mdr-1 gene which encodes P-glycoprotein was successfully cloned in 1986. To investigate P-glycoprotein expression in diverse ovarian tumors, including benign, low malignant potential and malignant, immunohistochemical study was done using a monoclonal antibody (C 219). Overall, 8 out of the 59 epithelial ovarian tumors (13.6%) expressed P-glycoprotein. It was noted that 5 of the 12 mucinous tumors were found to express P-glycoprotein, while none of the 31 serous tumors were immunohistochemically positive. In 10 malignant ovarian tumors, P-glycoprotein immunostaining was examined both prior to and after chemotherapy. Nine of them did not express any P-glycoprotein before or after chemotherapy. However, one tumor expressed P-glycoprotein after six courses of multidrug resistance-related drug administration. These findings indicate that P-glycoprotein expression is not so common in ovarian tumors, regardless of their malignant potential. Nevertheless, the results suggest a strong association between P-glycoprotein expression and certain histological cell types in epithelial ovarian tumors. It is also possible that P-glycoprotein appears as a result of chemotherapy, but such a phenomenon can not occur unless chemotherapy is administered at high doses for a long period of time.</p