We examined the relationship between the carbonizing temperature of bamboo carbide made from Moso bamboo (Phyllostachys pubescens) and the removal effect of harmful gases and odorants, and the use of a bamboo charcoal as a countermeasure for "Sick Building Syndrome" or "Chemical Sensitivity" and the use as a deodorant. With regard to the carbonizing temperature of the bamboo charcoal, a temperature sensor was installed inside each bamboo material and the carbonizing temperature was controlled at 500, 700 and 1000ºC. The removal effect was tested for formaldehyde, toluene and benzene that are known to cause "Sick Building Syndrome" or "Chemical Sensitivity" and for ammonia, indole, skatole and nonenal as odorants. The formaldehyde removal effect was only slightly different in the charcoal at all the carbonizing temperatures. The benzene, toluene, indole, skatole and nonenal removal effect were the highest for the bamboo charcoal carbonized at 1000ºC and tended to increase as the carbonizing temperature of the bamboo charcoal increased. The removal effect for ammonia was the highest on the bamboo charcoal carbonized at 500ºC. It is concluded that the effective carbonizing temperature is different for each chemical, and a charcoal must be specifically selected for use as an adsorbent or deodorant.

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Schooling behaviour and histological retinal light adaptation in juvenile Pacific bluefin tunaThunnus orientalis were examined under various light intensities to determine the effect of light intensity on behaviour. After monitoring the schooling behaviour of juveniles 35-36 and 45-46 days post hatching, schooling variables such as nearest neighbour distance and separation swimming index were measured under different light intensities. Furthermore, retinal indices of light adaptation were investigated histologically for each experimental light intensity. Under intensities >5 lx, schooling variables in the two juvenile growth stages were nearly constant, allowing schooling. In contrast, the schooling variables indicated that the fish gradually swam more widely and randomly with decreasing light intensities <5 lx. The retinal indices also showed a shift from light adaptation to dark adaptation at light levels <5 lx. From 5 to 0Á01 lx, retinal adaptation and fish schooling behaviour changed with light intensity. These data suggest that the schooling behaviour of juvenile Pacific bluefin tuna is greatly affected by retinal adaptation.

Between September 1996 and March 1999, a total of 135 fish species in 43 families were recorded from the mangrove estuary of Sikao Creek, Trang Province, Thailand, using two sizes of beach seine and a bag net. A checklist of the species is given, with preliminary descriptions of their assemblage structure. In terms of the number of species per family, Gobiidae was the most diverse (28 species), followed by Leiognathidae (11 species) and Engraulidae (10 species). In terms of individual numbers, Engraulidae, Leiognathidae and Ambassidae were the most dominant, whereby the 20 most abundant species comprised 88.5% of the total number of individuals collected. The fish assemblage structure was compared with published accounts of other tropical Indo‐West Pacific mangrove estuaries, and found to be similar to those of tropical Australia. Although a grater number of species were recorded from Sikao Creek than in comparable studies in other geographic regions, all of the studies were similar in that they have relatively few species that are clearly dominant in abundance.

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