The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brit...The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brittle fault system. There are three types of primary ore including auriferous calcite vein type, disseminated type, and breccia type, and the first two are important in the Phapon gold deposit. Based on fluid inclusion petrography and microthermometry, three types of primary fluid inclusions including type 1 liquid-rich aqueous, type 2 vapor-rich aqueous and type 3 daughter mineralbearing aqueous were identified in hydrothermal calcite grains. The ore-forming fluids are normally homogeneous, as indicated by the widespread type 1 inclusions with identical composition. The coexistence of type 1 and type 2 inclusions, showing similar final homogenization temperature but different compositions, indicate that fluid immiscibility did locally take place in both two types of ores. The results of microthermometry and H-O isotopes geochemistry indicate that there are little differences on ore-fluid geochemistry between the auriferous calcite vein-type and disseminated type ores. The oreforming fluids are characterized by medium-low temperatures(157–268 oC) and low salinity(1.6 wt.%–9.9 wt.% NaCl eq.). It is likely to have a metamorphic-dominant mixed source, which could be associated with dehydration and decarbonisation of Lower Permian limestone and Middle–Upper Triassic sandstones during the dynamic metamorphism. The fluid-wallrock interaction played a major role, and the locally occurred fluid-immiscible processes played a subordinate role in gold precipitation. Combined with the regional and ore deposit geology, and ore-fluid geochemistry, we suggest that the Phapon gold deposit is best considered to be a member of the epizonal orogenic deposit class.展开更多
The highly conserved Notch signaling is precisely regulated at different steps in a series of developmental events. However, little is known about the regulation of Notch receptor at transcriptional level. Here, we de...The highly conserved Notch signaling is precisely regulated at different steps in a series of developmental events. However, little is known about the regulation of Notch receptor at transcriptional level. Here, we demonstrate that dBrmsl is involved in regulating Notch signaling in Drosophila wing. We show that knockdown of dBrmsl by RNA interference （RNAi） in wing disc suppresses the expression of Notch signaling target genes wingless （wg）, cut and Enhancer of split m8 [E（spl）m8]. Consistently, the levels of Wg and Cut are reduced in the dBrmsl mutant clones. Importantly, loss of dBrmsl leads to significant reduction of Notch proteins. Furthermore, depletion of dBrmsl results in apparent downregulation of Notch transcription in the wing disc. Moreover, we find that dBrmsl is functionally conserved with human Breast cancer metastasis suppressor 1 like （hBRMSIL） in the modulation of Notch signaling. Taken together, our data provide important insights into the biological function of dBrmsl in regulating Notch signaling.展开更多
An understanding of the particle transport characteristics in a branched network helps to predict the particle distribution and prevent undesired plugging in various engineering systems.Quantitative analysis of partic...An understanding of the particle transport characteristics in a branched network helps to predict the particle distribution and prevent undesired plugging in various engineering systems.Quantitative analysis of particle flow characteristics is challenging in that experiments are expensive and particle flow is difficult to detect without disturbing the flow.To overcome this difficulty,man-made fractal tree-like branched networks were built,and a coupled computational fluid dynamic and discrete element method model was applied.A series of numerical simulations was carried out to analyze the influence of fractal structure parameters of networks on the particle flow characteristics.The joint influence of inertial,shunt capacity and superposition from upstream branches on particle flow was investigated.The injection position at the inlet determined the particle velocity and its future flow path.The particle density ratio,particle size and bifurcation angle had a greater influence on the shunting of K2 branches than that in the K1 level and N_(k22)/N_(k21) reached a maximum at 60°.Compared with a network with an even number of branches,there was a preferential branch when the branch number was odd.The preferential branch effect or asymmetry degree of the level(K2)branches had a more significant impact on particle shunting than that from the upstream branches(K1).展开更多
基金financially supported by the China Geological Survey Project (No. 121201010000150013)
文摘The Phapon gold deposit, located in northern Laos, is a unique large-scale gold deposit in Luang Prabang-Loei metallogenic belt. It is hosted in the Lower Permian limestone and controlled by a NE-trending ductile-brittle fault system. There are three types of primary ore including auriferous calcite vein type, disseminated type, and breccia type, and the first two are important in the Phapon gold deposit. Based on fluid inclusion petrography and microthermometry, three types of primary fluid inclusions including type 1 liquid-rich aqueous, type 2 vapor-rich aqueous and type 3 daughter mineralbearing aqueous were identified in hydrothermal calcite grains. The ore-forming fluids are normally homogeneous, as indicated by the widespread type 1 inclusions with identical composition. The coexistence of type 1 and type 2 inclusions, showing similar final homogenization temperature but different compositions, indicate that fluid immiscibility did locally take place in both two types of ores. The results of microthermometry and H-O isotopes geochemistry indicate that there are little differences on ore-fluid geochemistry between the auriferous calcite vein-type and disseminated type ores. The oreforming fluids are characterized by medium-low temperatures(157–268 oC) and low salinity(1.6 wt.%–9.9 wt.% NaCl eq.). It is likely to have a metamorphic-dominant mixed source, which could be associated with dehydration and decarbonisation of Lower Permian limestone and Middle–Upper Triassic sandstones during the dynamic metamorphism. The fluid-wallrock interaction played a major role, and the locally occurred fluid-immiscible processes played a subordinate role in gold precipitation. Combined with the regional and ore deposit geology, and ore-fluid geochemistry, we suggest that the Phapon gold deposit is best considered to be a member of the epizonal orogenic deposit class.
基金supported by the grants from National Basic Research Program of China (Nos.2011CB943901, 2011CB943902 and 2011CB943802)the National Natural Science Foundation of China (Nos.31030049, 31271582 and 31071284)the Strategic Priority Research Program of the Chinese Academy of Sciences(No. XDA01010101)
文摘The highly conserved Notch signaling is precisely regulated at different steps in a series of developmental events. However, little is known about the regulation of Notch receptor at transcriptional level. Here, we demonstrate that dBrmsl is involved in regulating Notch signaling in Drosophila wing. We show that knockdown of dBrmsl by RNA interference （RNAi） in wing disc suppresses the expression of Notch signaling target genes wingless （wg）, cut and Enhancer of split m8 [E（spl）m8]. Consistently, the levels of Wg and Cut are reduced in the dBrmsl mutant clones. Importantly, loss of dBrmsl leads to significant reduction of Notch proteins. Furthermore, depletion of dBrmsl results in apparent downregulation of Notch transcription in the wing disc. Moreover, we find that dBrmsl is functionally conserved with human Breast cancer metastasis suppressor 1 like （hBRMSIL） in the modulation of Notch signaling. Taken together, our data provide important insights into the biological function of dBrmsl in regulating Notch signaling.
基金Thig work was supportcd by the National Scicnce and Tech nology Major Project of the Ministry of Science and Technology of China(20172X05009-001)the National Natural Science Foun dation of China(No.J1930001,Nu.J1074208,Nu.J1304270,No.51504277.No.51774308 and No.51904321)+2 种基金the Shan dong Provincial Natural Science Foundation(ZR2019JQ21)the ulnllleltdl Resedltl Fulids fU1 the Celldl Uliveisities(Nu.17CX02008A,No.17CX05003,No.18CX02031A,No.18CX07012A and No.19CX05002A)Key Research and Development Plan of Shandong PToVince(2018GSF116009).
文摘An understanding of the particle transport characteristics in a branched network helps to predict the particle distribution and prevent undesired plugging in various engineering systems.Quantitative analysis of particle flow characteristics is challenging in that experiments are expensive and particle flow is difficult to detect without disturbing the flow.To overcome this difficulty,man-made fractal tree-like branched networks were built,and a coupled computational fluid dynamic and discrete element method model was applied.A series of numerical simulations was carried out to analyze the influence of fractal structure parameters of networks on the particle flow characteristics.The joint influence of inertial,shunt capacity and superposition from upstream branches on particle flow was investigated.The injection position at the inlet determined the particle velocity and its future flow path.The particle density ratio,particle size and bifurcation angle had a greater influence on the shunting of K2 branches than that in the K1 level and N_(k22)/N_(k21) reached a maximum at 60°.Compared with a network with an even number of branches,there was a preferential branch when the branch number was odd.The preferential branch effect or asymmetry degree of the level(K2)branches had a more significant impact on particle shunting than that from the upstream branches(K1).
