Multi-Wavelength Observation of Electron Acceleration in the 2006 December 13 Flare

We present a multi-wavelength observation of a solar flare occurring on 2006 December 13 with Hinode, RHESSI, and the Nobeyama Radio Observatory, to study the electron acceleration site and mechanism. The Solar Optical Telescope (SOT) on board Hinode observed elongated flare ribbons, and RHESSI observed double-footpoint hard X-ray (HXR) sources appearing in part of the ribbons. A photospheric vector magnetogram obtained from SOT reveals that the HXR sources are located at the region where horizontal magnetic fields change the direction. The region is interpreted as the footpoint of magnetic separatrix. Microwave images taken with the Nobeyama Radioheliograph show a loop structure connecting the HXR sources. The brighter parts of the microwave intensity are located between the top and footpoints of the loop. We consider these observations as an evidence of the electron acceleration near the magnetic separatrix and injection parallel to the field line.Comment: 20 pages, 7 figures, accepted by Ap

A new type of fish diet, non-fish meal extruded pellet for yellowtail, Seriola quinqueradiata

A non-fish meal diet using plant and/or animal protein materials for yellowtail, Seriola quinqueradiata was developed. Three kinds of non-fish meal diets and a control diet containing 50% fish meal were processed. In the non-fish meal diets, the fish meal was replaced with commercially available plant or animal materials and supplemented with taurine and other ingredients for maintaining palatability. These diets were fed to one year old yellowtail (body weight: 753±96 g) in net cages. No significant differences in growth, daily weight gain, daily feed rate, feed conversion ratio and protein efficiency ratio were observed among fish given the diets. Non-fish meal diets were processed in a factory and their biological characteristics were studied such as uptake, stomach evacuation rate, and disease resistance. In addition, the diet palatability of each substitute protein source for fish was examined and ingredients that enhanced palatability of the non-fish meal diets were identified. Non-fish meal diets have the potential to support the growth of one year old yellowtail

Induction of Plasma Vitellogenin Synthesis by the Commercial Fish Diets in Male Goldfish (Carassius auratus) and Dietary Phytoestrogens

In this study, we analyzed contents of phytoestrogens (genistein, daidzein, equol, and coumestrol) in two commercial fish diets [a diet for trout (TD) and a diet for ornamental carp (CD)] using Liquid Chromatography-Mass Spectroscopy/Mass Spectroscopy (LC-MS/MS), and these contents were compared with that of a casein-based formulated fish diet (FD) which does not contain soya bean or fish meal. We also analyzed phytoestrogen contents in commercial infant casein- and soya bean-based diets. The contents of phytoestorogens were generally high in CD, TD, and soya milk, and low or non-detectable in FD and casein-based milks. Among these samples, CD showed the highest phytoestrogen contents: genistein, 390800 ng/g; daidzein, 416800 ng/g; coumestrol, 1325 ng/g; equol, 6.4 ng/g. We also determined the estrogenic activity of the fish diets using male goldfish by measuring plasma vitellogenin (VTG) levels as a biomarker of estrogen exposure. When male goldfish were fed one of these diets for 31 days, plasma VTG was detected in CD-fed fish (78.01 ± 48.18 μg/ml) and TD-fed fish (3.51 ± 3.83 μg/ml), whereas plasma VTG was not detected in FD-fed fish (less than 0.040 μg/ml). These results indicate that the commercial fish diets examined contain a large amount of phytoestrogens and showed estrogenic activity that were strong enough to induce VTG production in male goldfish. It is necessary to eliminate estrogenic substances other than test chemicals in the screening test system for estrogenic endocrine-disrupting chemicals (EDCs). Since the formulated diet developed in the present study contain less phytoestrogens than the commercial fish diets and has low estrogenic activity, it is suggested that VTG production using male goldfish in combination with the low estrogen fish diet is a good in vivo system for evaluation of estrogenic effects of EDCs