Gonadal development and reproductive cycle of Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea were investigated based on monthly changes of gonadosomatic index, gametogenesis, and developmental phases of ovotestis. A. kurodai was simultaneous hermaphrodite; the ovotestis generally embedded in the posterior dorsal surface of the brownish digestive gland. The ovotestis is composed of a large number of follicles, and both oocytes and sperm are produced in the same follicles. In the sampling periods, the adult A. kurodai population have characteristic of seasonal pattern present during only 10 months. The reproductive cycle can be grouped into the following successive stages in the ovary: inactive (December to February), active (December to April), mature and spawning (April to September). The gonadal development of A. kurodai coincided with rising temperature, and spawning occurred from April to September, when the temperature was high. The histological observations of the ovotestis suggested that this species have a single spawning season that extend over six months.
Light characteristics are very specific in the aquatic environment. Fish vision and different light spectra perception are related to each species’ natural habit. Light is one of the main environmental conditions and can be easily manipulated in artificial rearing settings. Cholecystokinin (CCK) and mucus-secreting goblet cells are the main regulators of digestion. In this study, we established whether the light spectrum (natural condition, full spectrum: green, 520 nm; red, 590 nm, and blue, 480 nm) influences growth performance and digestive activity related to CCK mRNA expression and mucus-secreting goblet cell activity in order to develop a good management protocol and optimal rearing system for the longtooth grouper. For each light spectrum, fish were reared 12 weeks under a flow-through system and fed commercial pellet diets once daily. At the end of the experiment, the final body weights differed among the fish reared under different light spectra. The highest growth performance value was observed in fish reared under the green light condition. On the other hand, the growth performances of fish in the natural and blue light conditions were drastically decreased in last 3 weeks of the experiment. CCK mRNA expression and mucus-secreting goblet cell activity were significantly higher in the fish under green light condition than in the fish under the natural, red, and blue light conditions. Rearing of the longtooth grouper under the green light condition had positive effects on fish growth performance and digestion. We recommend that the appropriate light spectrum for the artificial culture of the longtooth grouper is the green light condition from the perspective of growth performance and the synergistic effects of CCK and mucus-secreting goblet cells. However, longer light treatment periods are needed in future investigations to clarify the effects of light spectrum on the longtooth grouper. Together with the findings of the present study, such studies would result in better understanding of the digestive physiology and contribute to the development of optimal rearing management for commercial production of the longtooth grouper.
One of challenging goals of developmental biology is understand of genetic inheritability of developmental programming. This challenging task first requires identification of all genetic factors and their functional dependences, revealing holistic view of genetic organization of cellular and organismal development. Because of high complexity of genotype as well as phenotype, genetic dissection of developmental programs could be even untouchable by combinatorial explosion of the number of possible associations. Therefore, modern genetics needs to be more systematic and predictive. Recently we proposed network-guided approach for genetics of complex traits. First, we construct probabilistic functional gene networks for cells or organisms by benchmarking and integrating heterogeneous multi-omics data that are in general publicly available. Then, using guilt-by-association, and other algorithms of network propagation of known biological information, we predict gene functions, phenotypic effect of loss-of-function, and epistatic interaction. The information can contribute to reconstruction of map between genotype and phenotype. The network-guided genetics method has been effectively applied for various organisms; from simple microbe yeast, to multicellular animal C. elegans, and to the human.
237Np is very important material in the fission products of nuclear reactors. Resonance integral(RI) tests of this material is necessary to check between the experiments and the evaluated data. Such feedback to the evaluated data is very important to correct data and improve of codes. The RI for the 237Np(n,γ)238Np reaction were measured by using the 46-MeV electron linear accelerator (linac) at the Research Reactor Institute, Kyoto University (KURRI). The measurement was performed in the energy region from 0.005 eV and 10 keV. RI obtained as 804.7 barns, compared with those of the evaluated data in JENDL-4.0 and Mughabghab.
In order to simulate a free surface flow in a trench channel, a three-dimensional incompressible unsteady Reynolds-averaged Navier-Stokes (RANS) equations are closed with the model. The artificial compressibility (AC) method is used. Because the pressure
This experiment was carried out to investigate the appropriate chilling requirements for breaking dormancy by treating the dormant plant of Hanabusaya asiatica with low temperature (4℃) for different time periods. The rates of sprouting and flowering were higher with longer treatment periods at low temperature. In addition, the growth and flowering of the plant were better when it was potted after treatment at a low temperature for 90 days. The abscisic acid levels and polyphenoloxidase activity of the dormant plant increased during the low temperature treatment, reached a climax 90 days and decreased thereafter. The catalase activity was the lowest after the low temperature treatment for 90 days and increased subsequently. The peroxidase activity increased and showed a sharp rise after the low temperature treatment for more than 90 days. Considering the physiological activities of the enzymes, the changes in the abscisic acid levels, and the characteristics of growth and flowering after sprouting of the plant, the appropriate cold periods required for breaking dormancy could be 90 days.
The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA) is a potent monoaminergic neurotoxin with the potential to cause serotonergic neurotoxicity, but has become a popular recreational drug. Little has been known about the cellular effects induced by MDMA. This report shows that MDMA inhibits neuronal cell growth and differentiation. MDMA suppressed neuronal cell growth. The results of quantitative real-time PCR analysis showed that Egr-1 expression is elevated in mouse embryo and neuroblastoma cells after MDMA treatment. Transiently transfected Egr-1 interfered with the neuronal differentiation of neuroblastoma cells such as SH-SY5Y and PC12 cells. These findings provide evidence that the abuse of MDMA during pregnancy may impair neuronal development via an induction of Egr-1 over-expression.