This paper deduced the temporal evolution of the magnetic field through a series of high-resolution vector magnetograms and calculated the fine distribution map of current density during an X9.3-class flare eruptions ...This paper deduced the temporal evolution of the magnetic field through a series of high-resolution vector magnetograms and calculated the fine distribution map of current density during an X9.3-class flare eruptions using Ampère's law.The results show that a pair of conjugate current ribbons exist on both sides of the magnetic neutral line in this active region,and these conjugate current ribbons persist before,during,and after the flare.It was observed that the X9.3-class flare brightened in the form of a bright core and evolved into a double-ribbon flare over time.Importantly,the position of the double-ribbon flare matches the position of the current ribbons with high accuracy,and their morphologies are very similar.By investigating the complexity of current density and flare morphology,we discovered a potential connection between the eruption of major flares and the characteristics of current density.展开更多
In this study, three cDNA sequences corresponding to cytochrome P450 C17(CYP17 Ⅰ), 3β-hydroxysteroid dehydrogenase(3β-HSD) and androgen receptor(AR) were isolated from spotted sea bass(Lateolabrax maculatus). The m...In this study, three cDNA sequences corresponding to cytochrome P450 C17(CYP17 Ⅰ), 3β-hydroxysteroid dehydrogenase(3β-HSD) and androgen receptor(AR) were isolated from spotted sea bass(Lateolabrax maculatus). The mRNA abundances of CYP17 Ⅰ and 3β-HSD increased from stage Ⅱ to stage V with a significant increase at stage Ⅴ, and the highest abundance of AR mRNA was detected at stage Ⅲ in testicular development cycle. CYP17 I, 3β-HSD and AR transcripts were obviously abundant in steroidogenesis tissues such as testis, brain, head kidney among others. Strong and positive signals were observed mainly in interstitial cell regions of L. maculatus testis as were measured with in situ hybridization method. Significant increases of CYP17 Ⅰ and3β-HSD transcripts were detected after 12-48 h hCG(human chorionic gonadotropin) and GnRHa(gonadotropin-releasing hormone analogue) treatments. However, an opposite relationship was found for AR in testis at the same time. In addition, decreasing trends of CYP17 Ⅰ and 3β-HSD mRNA were observed in testis of L. maculatus in freshwater group(FW) from day 2 to day 6, and mRNA abundance of AR increased in brackish water(BW) group from day 4 to day 8. These findings revealed that these three steroid synthesis genes are import for testicular development, hormone and salinity treatment, and provided also an insight into the mechanism of reproductive endocrine of L. maculatus.展开更多
The RNA helicase Vasa is an important regulator of primordial germ cell development. Its function in mature fish, espe- cially the hormone-related differences in maturing male fish has seldom been documented. In this ...The RNA helicase Vasa is an important regulator of primordial germ cell development. Its function in mature fish, espe- cially the hormone-related differences in maturing male fish has seldom been documented. In this study, a full length cDNA sequence of the vasa gene was cloned from Japanese sea bass, Lateolabraxjaponicas, and it was namedjsb-vasa. Homology analysis showed thatjsb-vasa was closely related to its teleost homologs. The spatial distribution ofjsb-vasa indicated that it was only highly ex- pressed in testis, showing its germ cell-specific expression pattern. During the testicular development cycle, jsb-vasa was highly expressed during early period of spermatogenesis, and reduced when spermatogenesis advanced. In addition, the jsb-vasa gene ex- pression was significantly inhibited at 6 h, 12 h and 24 h after injecting hCG （human ehorionic gonadotropin） and GnRHa （Gonad- otropin-releasing hormone analogue）, indicating thatjsb-vasa gene may play an important role in spermatogenesis of Japanese sea bass, and be under the regulation of external sex hormones.展开更多
基金supported by the Natural Natural Science Foundation of China(NSFC,grant No.12303062)Sichuan Science and Technology Program(2023NSFSC1351)+1 种基金Joint Funds of the National Natural Science Foundation of China(NSFC,grant No.U1931116)the Project Supported by the Specialized Research Fund for State Key Laboratories。
文摘This paper deduced the temporal evolution of the magnetic field through a series of high-resolution vector magnetograms and calculated the fine distribution map of current density during an X9.3-class flare eruptions using Ampère's law.The results show that a pair of conjugate current ribbons exist on both sides of the magnetic neutral line in this active region,and these conjugate current ribbons persist before,during,and after the flare.It was observed that the X9.3-class flare brightened in the form of a bright core and evolved into a double-ribbon flare over time.Importantly,the position of the double-ribbon flare matches the position of the current ribbons with high accuracy,and their morphologies are very similar.By investigating the complexity of current density and flare morphology,we discovered a potential connection between the eruption of major flares and the characteristics of current density.
基金supported by the Chinese Agriculture Research System (No. CARS-47)Shandong Provincial Natural Science Foundation (No. ZR2016CQ21)the Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (No. 2018008)
文摘In this study, three cDNA sequences corresponding to cytochrome P450 C17(CYP17 Ⅰ), 3β-hydroxysteroid dehydrogenase(3β-HSD) and androgen receptor(AR) were isolated from spotted sea bass(Lateolabrax maculatus). The mRNA abundances of CYP17 Ⅰ and 3β-HSD increased from stage Ⅱ to stage V with a significant increase at stage Ⅴ, and the highest abundance of AR mRNA was detected at stage Ⅲ in testicular development cycle. CYP17 I, 3β-HSD and AR transcripts were obviously abundant in steroidogenesis tissues such as testis, brain, head kidney among others. Strong and positive signals were observed mainly in interstitial cell regions of L. maculatus testis as were measured with in situ hybridization method. Significant increases of CYP17 Ⅰ and3β-HSD transcripts were detected after 12-48 h hCG(human chorionic gonadotropin) and GnRHa(gonadotropin-releasing hormone analogue) treatments. However, an opposite relationship was found for AR in testis at the same time. In addition, decreasing trends of CYP17 Ⅰ and 3β-HSD mRNA were observed in testis of L. maculatus in freshwater group(FW) from day 2 to day 6, and mRNA abundance of AR increased in brackish water(BW) group from day 4 to day 8. These findings revealed that these three steroid synthesis genes are import for testicular development, hormone and salinity treatment, and provided also an insight into the mechanism of reproductive endocrine of L. maculatus.
基金supported by the National Key Technologies R&D Program of China(2011BAD13B03)
文摘The RNA helicase Vasa is an important regulator of primordial germ cell development. Its function in mature fish, espe- cially the hormone-related differences in maturing male fish has seldom been documented. In this study, a full length cDNA sequence of the vasa gene was cloned from Japanese sea bass, Lateolabraxjaponicas, and it was namedjsb-vasa. Homology analysis showed thatjsb-vasa was closely related to its teleost homologs. The spatial distribution ofjsb-vasa indicated that it was only highly ex- pressed in testis, showing its germ cell-specific expression pattern. During the testicular development cycle, jsb-vasa was highly expressed during early period of spermatogenesis, and reduced when spermatogenesis advanced. In addition, the jsb-vasa gene ex- pression was significantly inhibited at 6 h, 12 h and 24 h after injecting hCG （human ehorionic gonadotropin） and GnRHa （Gonad- otropin-releasing hormone analogue）, indicating thatjsb-vasa gene may play an important role in spermatogenesis of Japanese sea bass, and be under the regulation of external sex hormones.
