During the Sino\|American Expedition to Mt. Qomolangma in May 1997, a 41m ice core was recovered from an elevation of 6500m from the northern branch firn basin of the Far East Rongbuk Glacier in Mt. Everest. The ice c...During the Sino\|American Expedition to Mt. Qomolangma in May 1997, a 41m ice core was recovered from an elevation of 6500m from the northern branch firn basin of the Far East Rongbuk Glacier in Mt. Everest. The ice core was dated down to 1814 by counting δ 18 O peaks and referring to the variations of β activity and major ion concentrations. The average annual accumulation is 224mm (ice equivalent). Five cold periods and five warm periods have been reconstructed from the ice core for the last 200 years and the general tendency of climatic change is warming, which is agree with the temperature change in the Northern Hemisphere. Also the climatic records in Far East Rongbuk ice core has good agreement with that in the Guliya ice core. This indicates that the climatic changes are consistent in the northwestern and southern Qinghai—Tibetan Plateau, and the ranges of climatic changes are larger in southern Plateau than that in northwestern Plateau. Though the δ 18 O variations has some negatively correlation with precipitation amount for short time scale, these do not effect δ 18 O changes reflecting temperature for long time scale.展开更多
Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of...Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in China. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North China. Remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57× 104 km2. The area of potential to slightly sandy desertified land is 13.93× 104 km2, moderately land 9.977×104 km2, severely land 7.909 ×104 km2 and very severely land 6.756×104 km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100 km2 ·a-1 in 1976-1988 to 3,600 km2 · a-1 in 1988-2000. The basic status of sandy desertification in North China is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North China can be restored under the conditions of rational land-use ways and intensity.展开更多
Based on historical documents, modern survey and statistics, as well as the result of predecessor studies, the trend and main process of forest dynamics are recognized. The forest area and forest coverage rates for ea...Based on historical documents, modern survey and statistics, as well as the result of predecessor studies, the trend and main process of forest dynamics are recognized. The forest area and forest coverage rates for each province of China from 1700 to 1949 are estimated backward by every 50 years. Linking the result with modern National Forest Inventory data, the spatial-temporal dynamics of Chinese forest in recent 300 years （AD 1700-1998） is quantitatively analyzed. The study shows that in recent 300 years, the forest area in current territory of China has declined by 0.95×10^8 hm^2 （or 9.2% of the coverage rate） in total, with a trend of decrease and recovery. Before the 1960s, there was a trend of accelerated descending. The forest area was reduced by 1.66×10^8 hm^2 （or 17% of the coverage rate） in 260 years. While after the 1960s, there has been a rapid increase. The forest area increased by 0.7×10^8 hm^2 （or 8% of the coverage rate） in 40 years. The study also shows that there is a significant spatial difference in the dynamics of forest. The amplitudes of increasing and decreasing in western China are both smaller than the ones in eastern China. During the rapid declining period from 1700 to 1949, the most serious decrease appeared in the Northeast, the Southwest and the Southeast, where the coverage rate in most provinces dropped over 20%. In Heilongjiang Province, the coverage rate dropped by 50%. In Jilin Province, it dropped by 36%. In Sichuan Province and Chongqing Municipality, it dropped by 42%. In Yunnan Province, it dropped by 35%. During the recovery period 1949-1998, the western provinces, municipality and autonomous regions, including Ningxia, Gansu, Inner Mongolia, Sichuan-Chongqing, Yunnan, Tibet, Xinjiang and Qinghai, etc, the increase rates are all below 5%, while the eastern provinces, municipality and autonomous regions （except Heilongjiang, Hubei, Jiangsu-Shanghai） have achieved an increase over 5%, among which the Guangdong-Hainan, Guangxi, Anhui, Beijing-Tianjin-Hebei, Shandong, Henan, Zhejiang, and Fujian have an increase over 10%.展开更多
The CC1 core, with a length of 216 cm, was drilled in the west part of the Chen Co (Lake) in southern Tibet Plateau. The210Pb and137Cs measurement indicated that it was a consecutive sedimentary sequence since ca. 140...The CC1 core, with a length of 216 cm, was drilled in the west part of the Chen Co (Lake) in southern Tibet Plateau. The210Pb and137Cs measurement indicated that it was a consecutive sedimentary sequence since ca. 1400 years. The ostracoda and their assemblages under the level of 1 cm samples’ cutting interval were finished for this core to reveal the past environmental changes in the lake area. A total of 15 species of ostracods belonging to 7 genera in the core sediments had been identified. According to the ostracod distributions, abundances and preservations in the core, seven ostracod assemblages had been distinguished. The ostracod assemblages and their ecological features, together with the sediments dating decision were used to infer the past ca. 1400 years environmental changes of the Chen Co environmental evolutions in three stages, which had responded to the Medieval Ages Warm-period (MAW), the Little Ice Age (LIA) and modern warm period. The results show that the changes of the Chen Co environment had been mainly influenced by the climatic variations. The trend of the lake level fluctuations had been accorded with that of climatic variation during the past 1400 years.展开更多
China has the biggest rare earths resource in the world,no wonder she pays much at-tention to the application of rare earth metals (REM).The application of REM in iron andsteel in China began at the end of 1950’s.The...China has the biggest rare earths resource in the world,no wonder she pays much at-tention to the application of rare earth metals (REM).The application of REM in iron andsteel in China began at the end of 1950’s.The production of REM-treated iron and steelhad been made steady progress in the period of 1980’s.The production of REM-treatediron and steel in 1989 was 1.4 million tons and 250,000 tons respectively.The interest oftreating steel with REM in China keeps growing even in these years,It comes from the nat-展开更多
The words---coordination, coordination abilities and coordination training are getting more and more popular among the coaches in different sports. The rhythm makes the movement logical, easy and correct done. The pur...The words---coordination, coordination abilities and coordination training are getting more and more popular among the coaches in different sports. The rhythm makes the movement logical, easy and correct done. The purpose of this study is to determine any difference between the coordination abilities of 10-11 years old gifts practicing basketball and rhythmic gymnastics. In that study, we have tested 40 girls at the age of 10-11 years practicing basketball and rhythmic gymnastic. We have tested them by 7 coordination tests. The results from the tests have been calculated in math-statistic methods and we have used descriptive statistic and t-test by Student with guaranteed probability Pt 〉 95 %. Ten-eleven old girls practicing rhythmic gymnastic have advantage against the girls practicing basketball in all 7 tests examining coordination abilities. The girls practicing rhythmic gymnastic, guaranteed by statistic, have better results in the balance and rhythmic abilities than the girls practicing basketball game. That statement is showing us that at this age the rhythmic gymnastic or elements from rhythmic gymnastic should be used for developing balance and rhythmic ability, which are very important for the basketball game.展开更多
Objectives:We aim to describe the efficacy,safety,and characteristics of the Amplatzer Vascular Plug(AVP)II and IV“off-label”use for multiple cardiovascular occlusions in children under 10 years.Methods:Observationa...Objectives:We aim to describe the efficacy,safety,and characteristics of the Amplatzer Vascular Plug(AVP)II and IV“off-label”use for multiple cardiovascular occlusions in children under 10 years.Methods:Observational retrospective multicenter(2007–2020,6 centers)review of paediatric procedures using AVP II or IV.Results:A total of 125 children(49.6%aged≤1 year,147 lesions)underwent 136 successive procedures(success rate:98.5%)using 169 devices(109 AVP IV,60 AVP II).The mean device diameter was 7.7±3.2 mm(4–20 mm).The median AVP size to vessel diameter ratio was 1.3(0–2).The median age and weight at implantation were 1.0 year(0.01–9.98)and 8.4 kg(1–69).Procedures were heterogeneous(55 patent ductus arteriosus(PDA),28 collaterals,18 sequestrations,22 arteriovenous/veinovenous/coronary fistulas,6 vertical veins,6 conduits,5 ventricular septal defects,7 miscellaneous).Day 1 and 6-month occlusion rates were respectively 94.8%and 98.5%.Major adverse events(MAE)occurred in 5.2%of cases(no procedure-related deaths),and more frequently in weight≤5 kg(p=0.01),younger patients(p=0.03)during PDA closure(p=0.02)of tubular types(p=0.02)using larger devices(p=0.03)and AVP II(p=0.003).Independent predictor of MAE risk was a higher AVP diameter to patient weight ratio(Odds-ratio:2.33,95%confidence interval 1.31–4.13,p=0.004,optimal cut off:1.45).Conclusions:Both AVPs are safe and effective for percutaneous occlusions in children under 10.Such devices represent an alternative“off label”use for well selected paediatric patients.展开更多
China’s auto industry has gradually been transformed from the original extensive operation, to readjustment and steady growth since 1993. It has begun to concentrate on the development of new leading brands and the d...China’s auto industry has gradually been transformed from the original extensive operation, to readjustment and steady growth since 1993. It has begun to concentrate on the development of new leading brands and the diversification of its automobiles, with multi-grades and functions. The steady increase in output of automobiles is a significant feature in China’s auto industry in recent years. In the 1980s, the industry developed rapidly, with fluctuations at times.展开更多
This article is a detailed abstract of the strategic objectives and policy suggestions for China’s sustainable development in the national 10th Five-year Plan (2001-2005) and the decade-long National Scheme by 2010, ...This article is a detailed abstract of the strategic objectives and policy suggestions for China’s sustainable development in the national 10th Five-year Plan (2001-2005) and the decade-long National Scheme by 2010, proposed in a report on China’s current actualities by a joint research team on national conditions of the Chinese Academy of Sciences and Tsinghua University.展开更多
The Beizhuangcun profile located at Weinan County, Shaanxi Province at an altitude of 570 m a. s. l. (34°30′N, 109°30′ E) is 16.5 m thick and is located at the eastern bank of Zhuoshui River (muddy river),...The Beizhuangcun profile located at Weinan County, Shaanxi Province at an altitude of 570 m a. s. l. (34°30′N, 109°30′ E) is 16.5 m thick and is located at the eastern bank of Zhuoshui River (muddy river), a west tributary of You River upstream. The profile records the relative continuous sedimentation sequences of about 30,000 a B. P. and is des-展开更多
文摘During the Sino\|American Expedition to Mt. Qomolangma in May 1997, a 41m ice core was recovered from an elevation of 6500m from the northern branch firn basin of the Far East Rongbuk Glacier in Mt. Everest. The ice core was dated down to 1814 by counting δ 18 O peaks and referring to the variations of β activity and major ion concentrations. The average annual accumulation is 224mm (ice equivalent). Five cold periods and five warm periods have been reconstructed from the ice core for the last 200 years and the general tendency of climatic change is warming, which is agree with the temperature change in the Northern Hemisphere. Also the climatic records in Far East Rongbuk ice core has good agreement with that in the Guliya ice core. This indicates that the climatic changes are consistent in the northwestern and southern Qinghai—Tibetan Plateau, and the ranges of climatic changes are larger in southern Plateau than that in northwestern Plateau. Though the δ 18 O variations has some negatively correlation with precipitation amount for short time scale, these do not effect δ 18 O changes reflecting temperature for long time scale.
文摘Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in China. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North China. Remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57× 104 km2. The area of potential to slightly sandy desertified land is 13.93× 104 km2, moderately land 9.977×104 km2, severely land 7.909 ×104 km2 and very severely land 6.756×104 km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100 km2 ·a-1 in 1976-1988 to 3,600 km2 · a-1 in 1988-2000. The basic status of sandy desertification in North China is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North China can be restored under the conditions of rational land-use ways and intensity.
基金National Natural Science Foundation of China, No.40471007 No.40571007 Knowledge Innovation Project of CAS, No.KZCX2-YW-315-4
文摘Based on historical documents, modern survey and statistics, as well as the result of predecessor studies, the trend and main process of forest dynamics are recognized. The forest area and forest coverage rates for each province of China from 1700 to 1949 are estimated backward by every 50 years. Linking the result with modern National Forest Inventory data, the spatial-temporal dynamics of Chinese forest in recent 300 years （AD 1700-1998） is quantitatively analyzed. The study shows that in recent 300 years, the forest area in current territory of China has declined by 0.95×10^8 hm^2 （or 9.2% of the coverage rate） in total, with a trend of decrease and recovery. Before the 1960s, there was a trend of accelerated descending. The forest area was reduced by 1.66×10^8 hm^2 （or 17% of the coverage rate） in 260 years. While after the 1960s, there has been a rapid increase. The forest area increased by 0.7×10^8 hm^2 （or 8% of the coverage rate） in 40 years. The study also shows that there is a significant spatial difference in the dynamics of forest. The amplitudes of increasing and decreasing in western China are both smaller than the ones in eastern China. During the rapid declining period from 1700 to 1949, the most serious decrease appeared in the Northeast, the Southwest and the Southeast, where the coverage rate in most provinces dropped over 20%. In Heilongjiang Province, the coverage rate dropped by 50%. In Jilin Province, it dropped by 36%. In Sichuan Province and Chongqing Municipality, it dropped by 42%. In Yunnan Province, it dropped by 35%. During the recovery period 1949-1998, the western provinces, municipality and autonomous regions, including Ningxia, Gansu, Inner Mongolia, Sichuan-Chongqing, Yunnan, Tibet, Xinjiang and Qinghai, etc, the increase rates are all below 5%, while the eastern provinces, municipality and autonomous regions （except Heilongjiang, Hubei, Jiangsu-Shanghai） have achieved an increase over 5%, among which the Guangdong-Hainan, Guangxi, Anhui, Beijing-Tianjin-Hebei, Shandong, Henan, Zhejiang, and Fujian have an increase over 10%.
基金National Natural Science Foundation of China, No.G1998040800Chinese Academy of Sciences+1 种基金No.KZCX2-314-2Knowledge Innovation Project of IGSNRR, CAS, No.CXIOG-A1-02
文摘The CC1 core, with a length of 216 cm, was drilled in the west part of the Chen Co (Lake) in southern Tibet Plateau. The210Pb and137Cs measurement indicated that it was a consecutive sedimentary sequence since ca. 1400 years. The ostracoda and their assemblages under the level of 1 cm samples’ cutting interval were finished for this core to reveal the past environmental changes in the lake area. A total of 15 species of ostracods belonging to 7 genera in the core sediments had been identified. According to the ostracod distributions, abundances and preservations in the core, seven ostracod assemblages had been distinguished. The ostracod assemblages and their ecological features, together with the sediments dating decision were used to infer the past ca. 1400 years environmental changes of the Chen Co environmental evolutions in three stages, which had responded to the Medieval Ages Warm-period (MAW), the Little Ice Age (LIA) and modern warm period. The results show that the changes of the Chen Co environment had been mainly influenced by the climatic variations. The trend of the lake level fluctuations had been accorded with that of climatic variation during the past 1400 years.
文摘China has the biggest rare earths resource in the world,no wonder she pays much at-tention to the application of rare earth metals (REM).The application of REM in iron andsteel in China began at the end of 1950’s.The production of REM-treated iron and steelhad been made steady progress in the period of 1980’s.The production of REM-treatediron and steel in 1989 was 1.4 million tons and 250,000 tons respectively.The interest oftreating steel with REM in China keeps growing even in these years,It comes from the nat-
文摘The words---coordination, coordination abilities and coordination training are getting more and more popular among the coaches in different sports. The rhythm makes the movement logical, easy and correct done. The purpose of this study is to determine any difference between the coordination abilities of 10-11 years old gifts practicing basketball and rhythmic gymnastics. In that study, we have tested 40 girls at the age of 10-11 years practicing basketball and rhythmic gymnastic. We have tested them by 7 coordination tests. The results from the tests have been calculated in math-statistic methods and we have used descriptive statistic and t-test by Student with guaranteed probability Pt 〉 95 %. Ten-eleven old girls practicing rhythmic gymnastic have advantage against the girls practicing basketball in all 7 tests examining coordination abilities. The girls practicing rhythmic gymnastic, guaranteed by statistic, have better results in the balance and rhythmic abilities than the girls practicing basketball game. That statement is showing us that at this age the rhythmic gymnastic or elements from rhythmic gymnastic should be used for developing balance and rhythmic ability, which are very important for the basketball game.
文摘Objectives:We aim to describe the efficacy,safety,and characteristics of the Amplatzer Vascular Plug(AVP)II and IV“off-label”use for multiple cardiovascular occlusions in children under 10 years.Methods:Observational retrospective multicenter(2007–2020,6 centers)review of paediatric procedures using AVP II or IV.Results:A total of 125 children(49.6%aged≤1 year,147 lesions)underwent 136 successive procedures(success rate:98.5%)using 169 devices(109 AVP IV,60 AVP II).The mean device diameter was 7.7±3.2 mm(4–20 mm).The median AVP size to vessel diameter ratio was 1.3(0–2).The median age and weight at implantation were 1.0 year(0.01–9.98)and 8.4 kg(1–69).Procedures were heterogeneous(55 patent ductus arteriosus(PDA),28 collaterals,18 sequestrations,22 arteriovenous/veinovenous/coronary fistulas,6 vertical veins,6 conduits,5 ventricular septal defects,7 miscellaneous).Day 1 and 6-month occlusion rates were respectively 94.8%and 98.5%.Major adverse events(MAE)occurred in 5.2%of cases(no procedure-related deaths),and more frequently in weight≤5 kg(p=0.01),younger patients(p=0.03)during PDA closure(p=0.02)of tubular types(p=0.02)using larger devices(p=0.03)and AVP II(p=0.003).Independent predictor of MAE risk was a higher AVP diameter to patient weight ratio(Odds-ratio:2.33,95%confidence interval 1.31–4.13,p=0.004,optimal cut off:1.45).Conclusions:Both AVPs are safe and effective for percutaneous occlusions in children under 10.Such devices represent an alternative“off label”use for well selected paediatric patients.
文摘China’s auto industry has gradually been transformed from the original extensive operation, to readjustment and steady growth since 1993. It has begun to concentrate on the development of new leading brands and the diversification of its automobiles, with multi-grades and functions. The steady increase in output of automobiles is a significant feature in China’s auto industry in recent years. In the 1980s, the industry developed rapidly, with fluctuations at times.
文摘This article is a detailed abstract of the strategic objectives and policy suggestions for China’s sustainable development in the national 10th Five-year Plan (2001-2005) and the decade-long National Scheme by 2010, proposed in a report on China’s current actualities by a joint research team on national conditions of the Chinese Academy of Sciences and Tsinghua University.
基金Project supported by the National Natural Science Foundation of China (grant No, 4870145)
文摘The Beizhuangcun profile located at Weinan County, Shaanxi Province at an altitude of 570 m a. s. l. (34°30′N, 109°30′ E) is 16.5 m thick and is located at the eastern bank of Zhuoshui River (muddy river), a west tributary of You River upstream. The profile records the relative continuous sedimentation sequences of about 30,000 a B. P. and is des-
