By establishing a 3-dimensional hydrodynamic model of the Hongtang Bay and the validation tests,tidal currents of the area before and after the construction of the Sanya new airport project,which include two artificia...By establishing a 3-dimensional hydrodynamic model of the Hongtang Bay and the validation tests,tidal currents of the area before and after the construction of the Sanya new airport project,which include two artificial islands built respectively to accommodate the airport and its connected technology park,are simulated.The hydrodynamic impacts of the islands on the Hongtang Bay and surrounding waters were analyzed by comparing flow fields and velocities of tidal currents under the two conditions.展开更多
The annual bloom of the green macroalgal Ulva prolifera from May through July since 2008 and another of giant jellyfi sh Nemopilema nomurai from June through September have been frequent events in the Yellow Sea. Howe...The annual bloom of the green macroalgal Ulva prolifera from May through July since 2008 and another of giant jellyfi sh Nemopilema nomurai from June through September have been frequent events in the Yellow Sea. However, the patterns of benthic ciliate communities during and after the blooms are still not known. In combination with analyses of benthic environmental factors, we investigated the distribution and community composition of benthic ciliates in the Yellow Sea in July and November 2011. In July, ciliates had high standing crops and diversity in the northern Yellow Sea, and in the inshore area off the southern Shandong Peninsula, where large numbers of green macroalgae accumulated. In November, the abundance, biomass and diversity of ciliates were high in the sea areas off the Shandong Peninsula and Changjiang estuary, where a large quantity of jellyfi sh occurred in August. Neither the abundance nor the biomass had signifi cant diff erence between seasons, or between diff erent compartments of the Yellow Sea. The species number, and both Margalef and Shannon-Wiener indices of ciliates were all signifi cantly higher in November than in July. In both seasons, prostomateans and karyorelicteans consistently constituted the fi rst and second most important ciliate groups in biomass; and carnivorous ciliates constituted the primary feeding type in terms of biomass as well as species richness, followed by bacterivores, algivores and omnivores. Compared with that in June 2007 when no macroalgae occurred, the percentage of small-sized bacterivores(e.g. Metacystis spp., Euplotes spp. and scuticociliates) increased in July 2011. The proportion of carnivorous ciliates increased in November, and this increased dominance of carnivorous ciliates may be a response to the increase in predominance of heterotrophic nanofl agellates, which might in turn be ascribed to an eff ect of green macroalgal and giant jellyfi sh blooms in the Yellow Sea.展开更多
AIM:To compare rifaximin and insulin-like growth factor(IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.METHODS:Rats with CCl4-induced cirrhosis with ascites plus portal vein...AIM:To compare rifaximin and insulin-like growth factor(IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.METHODS:Rats with CCl4-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups:Cirrhosis;Cirrhosis + IGF-1;Cirrhosis + rifaximin;Controls;Controls + IGF-1;and Controls + rifaximin.An oral glutamine-challenge test was performed,and plasma and cerebral ammonia,glucose,bilirubin,transaminases,endotoxemia,brain water content and ileocecal cultures were measured and liver histology was assessed.RESULTS:Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups,and improved some liver function parameters(bilirubin,alanine aminotransferase and aspartate aminotransferase).These effects were associated with a significant reduction in cerebral water content.Blood and cerebral ammonia levels,and area-underthe-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group animals.By contrast,IGF-1 administration failed to improve most alterations observed in cirrhosis.CONCLUSION:By reducing gut bacterial overgrowth,only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema,alterations associated with hepatic encephalopathy.展开更多
The margin of the Greenland ice sheet has undergone rapid changes over the past decade as a result of the thinning, acceleration, and retreat of many fast-flowing tidewater outlet glaciers. Satellite observations show...The margin of the Greenland ice sheet has undergone rapid changes over the past decade as a result of the thinning, acceleration, and retreat of many fast-flowing tidewater outlet glaciers. Satellite observations show that three major tidewater outlet glaciers in Greenland retreated between 2000 and 2005, with synchronous increases in flow speed, causing a deficit in ice sheet mass budget and the potential for sea level rise. In this study, we investigated whether this acceleration was related to surface melt processes, and found that both flow speed and positive degree day (PDD) anomalies of the three glaciers varied together, indicating a causal relationship. Jakobshavn Isbr^e had lower flow speeds before 2000, during which PDD anomalies were negative, except for modest warming in 1993 and 1995. From 1999-2000, during which it is thought a threshold was passed, the flow speed of the glacier started to increase. However, the two glaciers in east Greenland showed a delayed response. Abrupt warming occurred in the vicinity of the two glaciers around 2001, but flow speed did not increase until 2003 for the Helheim Glacier, and until 2004 for the Kangerdlugssuaq Glacier. Furthermore, the two eastern glaciers switched to a deceleration mode more quickly than Jakobshavn lsbr^e. The observed differences in both acceleration and deceleration among the glaciers suggest that the relationship between surface melt and outlet glacier dynamics is not simple but complex.展开更多
In order to research possible influences of the adjustment of plant distribution on the development frequency of thunderstorms over the Leizhou Peninsula, mathematic statistic methods, including correlation analyses, ...In order to research possible influences of the adjustment of plant distribution on the development frequency of thunderstorms over the Leizhou Peninsula, mathematic statistic methods, including correlation analyses, 11 kinds of fitting models and all-variable regression methods, were used for analyses and research. The results show that the average trend of the number of annual thunderstorm days is descending obviously, and there are thunderstorms in all seasons, in which warm post-midday thunderstorms have taken up the most part, and high frequency is found from May to September, and the starting and ending dates of thunderstorms have a great annual discrepancy. The vegetation structure has been improved along with the reduction of rice fields and the area increment of sugarcane and fruits planting, which results in the decrease of the number of thunderstorm days; the change in the characteristics of winter spare fields, which is caused by the planting of vegetables, limits the formation of thunderstorms in early winter and late spring. Meanwhile, the area adjustment of peanut planting has little influence on the variation of thunderstorm days. The adjustment of principal crop distribution, such as rice, sugarcane, fruits and vegetables, may have obvious influence on the formation of thunderstorms, and sugarcane has the largest effect, followed in turn by rice, vegetables and fruits, and the adjustment of crop distribution has little influence on the starting and ending dates of thunderstorms.展开更多
Microbes and microbial carbonates in reef-flat and coral community dynamics and submarine geomorphologic features in reef crest and fore reef of Yongxing Island,the Xisha Islands,South China Sea,were studied by means ...Microbes and microbial carbonates in reef-flat and coral community dynamics and submarine geomorphologic features in reef crest and fore reef of Yongxing Island,the Xisha Islands,South China Sea,were studied by means of scuba diving,underwater investigation,and line intercept transect survey.Studies indicate a very high coral mortality with few living corals in the reef flat of Yongxing Island.Moreover,macro algae,sea grass and cyanobacteria are common in reef flat.Microbes and microbially induced carbonates occur in reef flat.Living corals grow mainly in the reef crest and fore reef,but are also declined dramatically.From coast to off shore,the southeast reef flat of Yongxing Island can be divided into beach,inner reef flat,outer reef flat,reef flat front(reef crest and fore reef),and fore-reef slope settings.Sedimentary facies include coast,reef flat,reef crest and fore reef,and fore-reef slope.Reefal carbonate sediments are composed of coral skeletons and framework,coral fragments,bioclasts,and lime mud.With the deterioration of environment and water quality,the coral communities tend to be distributed in the reef crest and fore reef with clean sea water,well circulation and moderate water energy.Reef flat is occupied mainly by the macro algae and Heliopora coerulea communities.The coverage statistics on the reef crest demonstrate that the coverage of Acropora cytherea is more than 28% and represents a dominant species with wave-resistant ecological type.Sedimentary characteristics and geomorphologic features are different between the southeast and northwest reef-flat fronts(reef crest and fore reef) of Yongxing Island.The former shows discontinuously tidal channels in outer reef flat and different dimensional and deep reef ponds in reef crest and fore reef,and the latter presents a typical spur-and-groove system.Microbes(cyanobacteria Lyngbya sp.) occur generally in the inner reef flat and reef ponds of reef crest with restricted water circulation.Widely algae growth indicates a eutrophic environment,and the common microbes on the coral surface in the reef flat and reef ponds also demonstrate eutrophication in seawater and deteriorated water quality.展开更多
文摘By establishing a 3-dimensional hydrodynamic model of the Hongtang Bay and the validation tests,tidal currents of the area before and after the construction of the Sanya new airport project,which include two artificial islands built respectively to accommodate the airport and its connected technology park,are simulated.The hydrodynamic impacts of the islands on the Hongtang Bay and surrounding waters were analyzed by comparing flow fields and velocities of tidal currents under the two conditions.
基金Supported by the National Basic Research Program of China(973 Program)(No.2011CB403604)the National Natural Science Foundation of China(Nos.41476144,41306153)
文摘The annual bloom of the green macroalgal Ulva prolifera from May through July since 2008 and another of giant jellyfi sh Nemopilema nomurai from June through September have been frequent events in the Yellow Sea. However, the patterns of benthic ciliate communities during and after the blooms are still not known. In combination with analyses of benthic environmental factors, we investigated the distribution and community composition of benthic ciliates in the Yellow Sea in July and November 2011. In July, ciliates had high standing crops and diversity in the northern Yellow Sea, and in the inshore area off the southern Shandong Peninsula, where large numbers of green macroalgae accumulated. In November, the abundance, biomass and diversity of ciliates were high in the sea areas off the Shandong Peninsula and Changjiang estuary, where a large quantity of jellyfi sh occurred in August. Neither the abundance nor the biomass had signifi cant diff erence between seasons, or between diff erent compartments of the Yellow Sea. The species number, and both Margalef and Shannon-Wiener indices of ciliates were all signifi cantly higher in November than in July. In both seasons, prostomateans and karyorelicteans consistently constituted the fi rst and second most important ciliate groups in biomass; and carnivorous ciliates constituted the primary feeding type in terms of biomass as well as species richness, followed by bacterivores, algivores and omnivores. Compared with that in June 2007 when no macroalgae occurred, the percentage of small-sized bacterivores(e.g. Metacystis spp., Euplotes spp. and scuticociliates) increased in July 2011. The proportion of carnivorous ciliates increased in November, and this increased dominance of carnivorous ciliates may be a response to the increase in predominance of heterotrophic nanofl agellates, which might in turn be ascribed to an eff ect of green macroalgal and giant jellyfi sh blooms in the Yellow Sea.
基金Supported by A grant from the Instituto de Salud CarlosTM,PI051371,PI080809
文摘AIM:To compare rifaximin and insulin-like growth factor(IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.METHODS:Rats with CCl4-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups:Cirrhosis;Cirrhosis + IGF-1;Cirrhosis + rifaximin;Controls;Controls + IGF-1;and Controls + rifaximin.An oral glutamine-challenge test was performed,and plasma and cerebral ammonia,glucose,bilirubin,transaminases,endotoxemia,brain water content and ileocecal cultures were measured and liver histology was assessed.RESULTS:Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups,and improved some liver function parameters(bilirubin,alanine aminotransferase and aspartate aminotransferase).These effects were associated with a significant reduction in cerebral water content.Blood and cerebral ammonia levels,and area-underthe-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group animals.By contrast,IGF-1 administration failed to improve most alterations observed in cirrhosis.CONCLUSION:By reducing gut bacterial overgrowth,only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema,alterations associated with hepatic encephalopathy.
基金Supported by the National Natural Science Foundation of China (No.40906096)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry (No. Y0GQ031001)
文摘The margin of the Greenland ice sheet has undergone rapid changes over the past decade as a result of the thinning, acceleration, and retreat of many fast-flowing tidewater outlet glaciers. Satellite observations show that three major tidewater outlet glaciers in Greenland retreated between 2000 and 2005, with synchronous increases in flow speed, causing a deficit in ice sheet mass budget and the potential for sea level rise. In this study, we investigated whether this acceleration was related to surface melt processes, and found that both flow speed and positive degree day (PDD) anomalies of the three glaciers varied together, indicating a causal relationship. Jakobshavn Isbr^e had lower flow speeds before 2000, during which PDD anomalies were negative, except for modest warming in 1993 and 1995. From 1999-2000, during which it is thought a threshold was passed, the flow speed of the glacier started to increase. However, the two glaciers in east Greenland showed a delayed response. Abrupt warming occurred in the vicinity of the two glaciers around 2001, but flow speed did not increase until 2003 for the Helheim Glacier, and until 2004 for the Kangerdlugssuaq Glacier. Furthermore, the two eastern glaciers switched to a deceleration mode more quickly than Jakobshavn lsbr^e. The observed differences in both acceleration and deceleration among the glaciers suggest that the relationship between surface melt and outlet glacier dynamics is not simple but complex.
文摘In order to research possible influences of the adjustment of plant distribution on the development frequency of thunderstorms over the Leizhou Peninsula, mathematic statistic methods, including correlation analyses, 11 kinds of fitting models and all-variable regression methods, were used for analyses and research. The results show that the average trend of the number of annual thunderstorm days is descending obviously, and there are thunderstorms in all seasons, in which warm post-midday thunderstorms have taken up the most part, and high frequency is found from May to September, and the starting and ending dates of thunderstorms have a great annual discrepancy. The vegetation structure has been improved along with the reduction of rice fields and the area increment of sugarcane and fruits planting, which results in the decrease of the number of thunderstorm days; the change in the characteristics of winter spare fields, which is caused by the planting of vegetables, limits the formation of thunderstorms in early winter and late spring. Meanwhile, the area adjustment of peanut planting has little influence on the variation of thunderstorm days. The adjustment of principal crop distribution, such as rice, sugarcane, fruits and vegetables, may have obvious influence on the formation of thunderstorms, and sugarcane has the largest effect, followed in turn by rice, vegetables and fruits, and the adjustment of crop distribution has little influence on the starting and ending dates of thunderstorms.
基金supported by National Natural Science Foundation of China (Grant Nos.40976030,41006029),Projects of International Cooperation and Exchanges of National Natural Science Foundation of China (Grant No.41210104029)Knowledge Innovation Program of Chinese Academy of Sciences (Grant No.SQ201114)
文摘Microbes and microbial carbonates in reef-flat and coral community dynamics and submarine geomorphologic features in reef crest and fore reef of Yongxing Island,the Xisha Islands,South China Sea,were studied by means of scuba diving,underwater investigation,and line intercept transect survey.Studies indicate a very high coral mortality with few living corals in the reef flat of Yongxing Island.Moreover,macro algae,sea grass and cyanobacteria are common in reef flat.Microbes and microbially induced carbonates occur in reef flat.Living corals grow mainly in the reef crest and fore reef,but are also declined dramatically.From coast to off shore,the southeast reef flat of Yongxing Island can be divided into beach,inner reef flat,outer reef flat,reef flat front(reef crest and fore reef),and fore-reef slope settings.Sedimentary facies include coast,reef flat,reef crest and fore reef,and fore-reef slope.Reefal carbonate sediments are composed of coral skeletons and framework,coral fragments,bioclasts,and lime mud.With the deterioration of environment and water quality,the coral communities tend to be distributed in the reef crest and fore reef with clean sea water,well circulation and moderate water energy.Reef flat is occupied mainly by the macro algae and Heliopora coerulea communities.The coverage statistics on the reef crest demonstrate that the coverage of Acropora cytherea is more than 28% and represents a dominant species with wave-resistant ecological type.Sedimentary characteristics and geomorphologic features are different between the southeast and northwest reef-flat fronts(reef crest and fore reef) of Yongxing Island.The former shows discontinuously tidal channels in outer reef flat and different dimensional and deep reef ponds in reef crest and fore reef,and the latter presents a typical spur-and-groove system.Microbes(cyanobacteria Lyngbya sp.) occur generally in the inner reef flat and reef ponds of reef crest with restricted water circulation.Widely algae growth indicates a eutrophic environment,and the common microbes on the coral surface in the reef flat and reef ponds also demonstrate eutrophication in seawater and deteriorated water quality.