To obtain carbon dioxide （CO2） flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide par...To obtain carbon dioxide （CO2） flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide partial pressures （pCO2） at air-water interface in the lake were calculated using alkalinity, pH, ionic strength, active coefficient, and water temperature. The carbon fluxes at different sublakes and areas were estimated by concentration gradient between water and air in consideration of Schmidt numbers of 600 and daily mean windspeed at 10 m above water surface. The results indicated that the mean values of pCO2 in Wuli Lake,Meiliang Bay, hydrophyte area, west littoral zone, riverine mouths, and the open lake areas were 1 807.8±1 071.4（mean±standard deviation）μatm （latm=1.013 25×10^5pa）, 416.3±217.0μatm, 576.5±758.8μatm, 304.2±9.43.5μatm, 1 933.6±1 144.7 μatm, and 448.5±202.6μatm, respectively. Maximum and minimum pCO2 values were found in the hypertrophic （4 053.7μatm） and the eutrophic （3.2 μatm） areas. The riverine mouth areas have the maximum fluxes （82.0±62.8 mmol/m^2a）. But there was no significant difference between eutrophic and mesotrophic areas in pCO2 and the flux of CO2. The hydrophyte area, however, has the minimum （--0.58±12.9mmol/m^2a）. In respect to CO2 equilibrium, input of the rivers will obviously influence inorganic carbon distribution in the riverine estuary. For example, the annual mean CO2 flux in Zhihugang River estuary was 19 times of that in Meiliang Bay, although the former is only a part of the latter. The sites in the body of the lake show a clear seasonal cycle with pCO2 higher than atmospheric equilibrium in winter, and much lower than atmospheric in summer due to CO2 consumption by photosynthesis. The CO2 amount of the net annual evasion that enters the atmosphere is 28.42×10^4 t/a, of which those from the west littoral zone and the open lake account for 53.8% and 36.7%, respectively.展开更多
BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation...BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation(CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fi brillation(VF) versus asphyxial cardiac arrest.METHODS: Sixty-two male Sprague-Dawley(SD) rats were randomly divided into an asphyxial group(n=32) and a VF group(n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest.RESULTS: The initial values of PETCO2 immediately after PC in the VF group were signifi cantly lower than those in the asphyxial group(12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation(ROSC), compared with those in rats without ROSC(16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were signifi cantly higher than those in rats without ROSC(20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic(ROC) curves of PETCO2 showed signifi cant sensitivity and specifi city for predicting ROSC in VF versus asphyxial cardiac arrest.CONCLUSIONS: The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR.展开更多
Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in ob...Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in obese patients during general anesthesia. Materials and Methods: From January 2003 to December 2013, we studied 601 patients aged 16 years old or over undergoing general anesthesia. Patients had American Society of Anesthesiology physical status I and II and we reviewed their anesthetic charts. The P(a-ET)CO2 with respect to the BKI divided patients into two groups: 16 to 2 values between the two groups. Results: In patients aged 16 to 2 was 2.2 ± 3.1 mmHg at BKI 2 was 3.2 ± 4.1 mmHg at BKI 2 tends to increase in obese patients during general anesthesia with increasing BKI in patients aged 16 to < 65 years old.展开更多
In the east of China＇s seas, there is a wide range of the continental shelf. The nutrient cycle and the carbon cycle in the east of China＇s seas exhibit a strong variability on seasonal to decadal time scales. On th...In the east of China＇s seas, there is a wide range of the continental shelf. The nutrient cycle and the carbon cycle in the east of China＇s seas exhibit a strong variability on seasonal to decadal time scales. On the basis of a regional ocean modeling system（ROMS）, a three dimensional physical-biogeochemical model including the carbon cycle with the resolution（1/12）°×（1/12）° is established to investigate the physical variations, ecosystem responses and carbon cycle consequences in the east of China＇s seas. The ROMS-Nutrient Phytoplankton Zooplankton Detritus（NPZD） model is driven by daily air-sea fluxes（wind stress, long wave radiation, short wave radiation, sensible heat and latent heat, freshwater fluxes） that derived from the National Centers for Environmental Prediction（NCEP） reanalysis2 from 1982 to 2005. The coupled model is capable of reproducing the observed seasonal variation characteristics over the same period in the East China Sea. The integrated air-sea CO_2 flux over the entire east of China＇s seas reveals a strong seasonal cycle, functioning as a source of CO_2 to the atmosphere from June to October, while serving as a sink of CO_2 to the atmosphere in the other months. The 24 a mean value of airsea CO_2 flux over the entire east of China＇s seas is about 1.06 mol/（m^2·a）, which is equivalent to a regional total of3.22 Mt/a, indicating that in the east of China＇s seas there is a sink of CO_2 to the atmosphere. The partial pressure of carbon dioxide in sea water in the east of China＇s seas has an increasing rate of 1.15 μatm/a（1μtm/a=0.101 325Pa）, but p H in sea water has an opposite tendency, which decreases with a rate of 0.001 3 a^（–1） from 1982 to 2005.Biological activity is a dominant factor that controls the pCO_2 air in the east of China＇s seas, and followed by a temperature. The inverse relationship between the interannual variability of air-sea CO_2 flux averaged from the domain area and Ni？o3 SST Index indicates that the carbon cycle in the east of China＇s seas has a high correlation with El Ni？o-Southern Oscillation（ENSO）.展开更多
The primary objective of this article is to analyze the role of tobacco smoke compounds able to damage the cardiovascular system and, in particular, to interfere with blood pressure. They are products of tobacco plant...The primary objective of this article is to analyze the role of tobacco smoke compounds able to damage the cardiovascular system and, in particular, to interfere with blood pressure. They are products of tobacco plant leaves, like nicotine, thiocyanate and aromatic amines, and a chemical derived from cigarette com-bustion, carbon monoxide. Of the other thousands of chemicals, there is no clear evidence of cardiovascular damage. Nicotine and its major metabolite, cotinine, usually increase blood pressure by a direct action and an action stimulating neuro-humoral metabolites of the body as well as sympathetic stimulation. An indirect mechanism of damage exerted by elevated carboxyhe-moglobin concentrations is mediated by carbon mon-oxide, which, mainly induces arterial wall damage and, consequently, late rising in blood pressure by a toxic direct action on endothelial and blood cells. Thiocya-nate, in turn, reinforces the hypoxic effects determined by carbon monoxide. Aromatic amines, depending on their chemical structure, may exert toxic effects on the cardiovascular system although they have little effect on blood pressure. A rise in blood pressure determined by smoking compounds is a consequence of both their direct toxicity and the characteristics of their chemical chains that are strongly reactive with a large number of molecules for their spatial shape. In addition, a rise in blood pressure has been documented in individuals smoking a cigarette, acutely and chronically, with irre-versible artery wall alterations several years after begin-ning smoking. Since cigarette smoking has a worldwide diffusion, the evidence of this topic meets the interest of both the scientifc community and those individuals aiming to control smoking.展开更多
Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studi...Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studied area was higher than that in the atmosphere with only exception of a patch east of Zhoushan Archipelago.The pCO2 varied from 168 to 2 264 μatm,which fell in the low range compared with those of other estuaries in the world.The calculated sea-air CO2 fluxes decreased offshore and varied from -10.0 to 88.1 mmol m-2 d-1 in average of 24.4 ± 16.5 mmol m-2 d-1.Although the area studied was estimated only 2 × 104 km2,it emitted(5.9 ± 4.0) × 103 tons of carbon to the atmosphere every day.The estuaries and their plumes must be further studied for better understanding the role of coastal seas playing in the global oceanic carbon cycle.展开更多
As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative ...As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative rates of photosynthesis and photorespiration are known to be responsive to changes in gas composition.However,comprehensive profiling methods have not yet been applied in order to characterize the wider consequences of these changes on primary metabolism in general.Moreover,although transcriptional profiling has revealed that a subset of photorespiratory enzymes are co-expressed,whether transcriptional responses play a role in short-term responses to atmospheric compositional changes remains unknown.To address these questions,plants Arabidopsis thaliana（Arabidopsis） ecotype Columbia（Col-O） grown under normal air conditions were transferred to different CO_2 and O_2 concentrations and characterized at the physiological,molecular,and metabolic levels following this transition.The results reveal alterations in the components,which are directly involved in,or supporting,photorespiration,including transcripts and metabolite levels.The results further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription and that the photorespiratory pathway is essential also in conditions in which flux through the pathway is minimized,yet suggest that flux through this pathway is not mediated at the level of transcription.展开更多
The sediment core DGKS9603 collected from the Okinawa Trough was used as research target. By use of unsaturated index U37^k of long-chain alkenone, δ^13C of POC and of planktonic foraminifera (G sacculifer), the evol...The sediment core DGKS9603 collected from the Okinawa Trough was used as research target. By use of unsaturated index U37^k of long-chain alkenone, δ^13C of POC and of planktonic foraminifera (G sacculifer), the evolutions of sea surface temperature and partial pressure of carbon dioxide in the atmosphere during the Holocene were reconstructed in the Okinawa Trough. And in combination of δ^18O of planktonic foraminifera, the relative difference of sea surface salinity during the Holocene was also reconstructed.Consequently, three cooling events (E1-E3) were identified,each of which occurred at 1.7-1.6, 5.1-4.8 and 8.1-7.4kaBP (cal), respectively. Of the three events, E2 and E3 are globally comparable, their occurrence mechanism would be that the main stream of the Kuroshio Current shifted eastward due to the enhanced circulation of the northeastern Pacific Ocean, which was driven in turn by amplified intensity of sunshine and subsequent enhancement of subtropical high pressure; E1 corresponds to the Small Ice-Age Event occurring between 1550 and 1850AD in China. In the Okinawa Trough, E1 might be also related to the eastward shift of main stream of the Kuroshio current driven by powerful Asia winter monsoon.展开更多
基金This research was supported by the Knowledge Innovation Project of Chinese Academy of Sciences (KZCX1-SW-01-15) and (KZCX1- SW-12)
文摘To obtain carbon dioxide （CO2） flux between water-air interface of Taihu lake, monthly water samplers at 14 sites and the local meteorological data of the lake were collected and analyzed in 1998. Carbon dioxide partial pressures （pCO2） at air-water interface in the lake were calculated using alkalinity, pH, ionic strength, active coefficient, and water temperature. The carbon fluxes at different sublakes and areas were estimated by concentration gradient between water and air in consideration of Schmidt numbers of 600 and daily mean windspeed at 10 m above water surface. The results indicated that the mean values of pCO2 in Wuli Lake,Meiliang Bay, hydrophyte area, west littoral zone, riverine mouths, and the open lake areas were 1 807.8±1 071.4（mean±standard deviation）μatm （latm=1.013 25×10^5pa）, 416.3±217.0μatm, 576.5±758.8μatm, 304.2±9.43.5μatm, 1 933.6±1 144.7 μatm, and 448.5±202.6μatm, respectively. Maximum and minimum pCO2 values were found in the hypertrophic （4 053.7μatm） and the eutrophic （3.2 μatm） areas. The riverine mouth areas have the maximum fluxes （82.0±62.8 mmol/m^2a）. But there was no significant difference between eutrophic and mesotrophic areas in pCO2 and the flux of CO2. The hydrophyte area, however, has the minimum （--0.58±12.9mmol/m^2a）. In respect to CO2 equilibrium, input of the rivers will obviously influence inorganic carbon distribution in the riverine estuary. For example, the annual mean CO2 flux in Zhihugang River estuary was 19 times of that in Meiliang Bay, although the former is only a part of the latter. The sites in the body of the lake show a clear seasonal cycle with pCO2 higher than atmospheric equilibrium in winter, and much lower than atmospheric in summer due to CO2 consumption by photosynthesis. The CO2 amount of the net annual evasion that enters the atmosphere is 28.42×10^4 t/a, of which those from the west littoral zone and the open lake account for 53.8% and 36.7%, respectively.
基金supported in part by grants from the National Natural Science Foundation of China(30700303)the National Clinical Key Subject Construction Project
文摘BACKGROUND: Partial pressure of end-tidal carbon dioxide(PETCO2) has been used to monitor the effectiveness of precordial compression(PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation(CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fi brillation(VF) versus asphyxial cardiac arrest.METHODS: Sixty-two male Sprague-Dawley(SD) rats were randomly divided into an asphyxial group(n=32) and a VF group(n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest.RESULTS: The initial values of PETCO2 immediately after PC in the VF group were signifi cantly lower than those in the asphyxial group(12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation(ROSC), compared with those in rats without ROSC(16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were signifi cantly higher than those in rats without ROSC(20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic(ROC) curves of PETCO2 showed signifi cant sensitivity and specifi city for predicting ROSC in VF versus asphyxial cardiac arrest.CONCLUSIONS: The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR.
文摘Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in obese patients during general anesthesia. Materials and Methods: From January 2003 to December 2013, we studied 601 patients aged 16 years old or over undergoing general anesthesia. Patients had American Society of Anesthesiology physical status I and II and we reviewed their anesthetic charts. The P(a-ET)CO2 with respect to the BKI divided patients into two groups: 16 to 2 values between the two groups. Results: In patients aged 16 to 2 was 2.2 ± 3.1 mmHg at BKI 2 was 3.2 ± 4.1 mmHg at BKI 2 tends to increase in obese patients during general anesthesia with increasing BKI in patients aged 16 to < 65 years old.
基金The National Key Research and Development Program of China under contract No.2016YFC1401605the National Key Research and Development Program of China under contract No.2016YFC1401605+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences under contract No.XDA 1102010403the National Natural Science Foundation of China under contract Nos 41222038,41206023 and 41076011the Public Science and Technology Research Funds projects of Ocean of China under contract No.201205018the Guangdong Provincial Key Laboratory of Fishery Ecology and Environment under contract No.LFE-2015-3
文摘In the east of China＇s seas, there is a wide range of the continental shelf. The nutrient cycle and the carbon cycle in the east of China＇s seas exhibit a strong variability on seasonal to decadal time scales. On the basis of a regional ocean modeling system（ROMS）, a three dimensional physical-biogeochemical model including the carbon cycle with the resolution（1/12）°×（1/12）° is established to investigate the physical variations, ecosystem responses and carbon cycle consequences in the east of China＇s seas. The ROMS-Nutrient Phytoplankton Zooplankton Detritus（NPZD） model is driven by daily air-sea fluxes（wind stress, long wave radiation, short wave radiation, sensible heat and latent heat, freshwater fluxes） that derived from the National Centers for Environmental Prediction（NCEP） reanalysis2 from 1982 to 2005. The coupled model is capable of reproducing the observed seasonal variation characteristics over the same period in the East China Sea. The integrated air-sea CO_2 flux over the entire east of China＇s seas reveals a strong seasonal cycle, functioning as a source of CO_2 to the atmosphere from June to October, while serving as a sink of CO_2 to the atmosphere in the other months. The 24 a mean value of airsea CO_2 flux over the entire east of China＇s seas is about 1.06 mol/（m^2·a）, which is equivalent to a regional total of3.22 Mt/a, indicating that in the east of China＇s seas there is a sink of CO_2 to the atmosphere. The partial pressure of carbon dioxide in sea water in the east of China＇s seas has an increasing rate of 1.15 μatm/a（1μtm/a=0.101 325Pa）, but p H in sea water has an opposite tendency, which decreases with a rate of 0.001 3 a^（–1） from 1982 to 2005.Biological activity is a dominant factor that controls the pCO_2 air in the east of China＇s seas, and followed by a temperature. The inverse relationship between the interannual variability of air-sea CO_2 flux averaged from the domain area and Ni？o3 SST Index indicates that the carbon cycle in the east of China＇s seas has a high correlation with El Ni？o-Southern Oscillation（ENSO）.
文摘The primary objective of this article is to analyze the role of tobacco smoke compounds able to damage the cardiovascular system and, in particular, to interfere with blood pressure. They are products of tobacco plant leaves, like nicotine, thiocyanate and aromatic amines, and a chemical derived from cigarette com-bustion, carbon monoxide. Of the other thousands of chemicals, there is no clear evidence of cardiovascular damage. Nicotine and its major metabolite, cotinine, usually increase blood pressure by a direct action and an action stimulating neuro-humoral metabolites of the body as well as sympathetic stimulation. An indirect mechanism of damage exerted by elevated carboxyhe-moglobin concentrations is mediated by carbon mon-oxide, which, mainly induces arterial wall damage and, consequently, late rising in blood pressure by a toxic direct action on endothelial and blood cells. Thiocya-nate, in turn, reinforces the hypoxic effects determined by carbon monoxide. Aromatic amines, depending on their chemical structure, may exert toxic effects on the cardiovascular system although they have little effect on blood pressure. A rise in blood pressure determined by smoking compounds is a consequence of both their direct toxicity and the characteristics of their chemical chains that are strongly reactive with a large number of molecules for their spatial shape. In addition, a rise in blood pressure has been documented in individuals smoking a cigarette, acutely and chronically, with irre-versible artery wall alterations several years after begin-ning smoking. Since cigarette smoking has a worldwide diffusion, the evidence of this topic meets the interest of both the scientifc community and those individuals aiming to control smoking.
基金Supported by the National Basic Research Program of China (973 Program, No. 2005CB407305)the open foundation of the Key Laboratory of Marine Sedimentology & Environmental Geology, SOA (No. MASEG200606)+1 种基金the Qingdao Special Program for Leading Scientists (No. 05-2-JC-90)the 100-Talent Project of the Chinese Academy of Sciences
文摘Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studied area was higher than that in the atmosphere with only exception of a patch east of Zhoushan Archipelago.The pCO2 varied from 168 to 2 264 μatm,which fell in the low range compared with those of other estuaries in the world.The calculated sea-air CO2 fluxes decreased offshore and varied from -10.0 to 88.1 mmol m-2 d-1 in average of 24.4 ± 16.5 mmol m-2 d-1.Although the area studied was estimated only 2 × 104 km2,it emitted(5.9 ± 4.0) × 103 tons of carbon to the atmosphere every day.The estuaries and their plumes must be further studied for better understanding the role of coastal seas playing in the global oceanic carbon cycle.
基金supported by funding from the Max Planck 682 Society(W.L.A.,Z.N.,T.T.,and A.R.F.)the Deutsche Forschungsgemeinschaft as part of PROMICS research group 1186(A.F.,S.T.,H.B.,and A.R.F.)
文摘As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the atmosphere.Given the indiscriminant nature of Rubisco,the relative rates of photosynthesis and photorespiration are known to be responsive to changes in gas composition.However,comprehensive profiling methods have not yet been applied in order to characterize the wider consequences of these changes on primary metabolism in general.Moreover,although transcriptional profiling has revealed that a subset of photorespiratory enzymes are co-expressed,whether transcriptional responses play a role in short-term responses to atmospheric compositional changes remains unknown.To address these questions,plants Arabidopsis thaliana（Arabidopsis） ecotype Columbia（Col-O） grown under normal air conditions were transferred to different CO_2 and O_2 concentrations and characterized at the physiological,molecular,and metabolic levels following this transition.The results reveal alterations in the components,which are directly involved in,or supporting,photorespiration,including transcripts and metabolite levels.The results further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription and that the photorespiratory pathway is essential also in conditions in which flux through the pathway is minimized,yet suggest that flux through this pathway is not mediated at the level of transcription.
文摘The sediment core DGKS9603 collected from the Okinawa Trough was used as research target. By use of unsaturated index U37^k of long-chain alkenone, δ^13C of POC and of planktonic foraminifera (G sacculifer), the evolutions of sea surface temperature and partial pressure of carbon dioxide in the atmosphere during the Holocene were reconstructed in the Okinawa Trough. And in combination of δ^18O of planktonic foraminifera, the relative difference of sea surface salinity during the Holocene was also reconstructed.Consequently, three cooling events (E1-E3) were identified,each of which occurred at 1.7-1.6, 5.1-4.8 and 8.1-7.4kaBP (cal), respectively. Of the three events, E2 and E3 are globally comparable, their occurrence mechanism would be that the main stream of the Kuroshio Current shifted eastward due to the enhanced circulation of the northeastern Pacific Ocean, which was driven in turn by amplified intensity of sunshine and subsequent enhancement of subtropical high pressure; E1 corresponds to the Small Ice-Age Event occurring between 1550 and 1850AD in China. In the Okinawa Trough, E1 might be also related to the eastward shift of main stream of the Kuroshio current driven by powerful Asia winter monsoon.
