Global temperatures will continue to increase in the future.The∼640,000-km2 Loess Plateau(LP)is a typical arid and semi-arid region in China.Similar regions cover∼41%of the Earth,and its soils are some of the most s...Global temperatures will continue to increase in the future.The∼640,000-km2 Loess Plateau(LP)is a typical arid and semi-arid region in China.Similar regions cover∼41%of the Earth,and its soils are some of the most severely eroded anywhere in the world.It is very important to understand the vegetation change and its ecological threshold under climate change on the LP for the sustainable development in the Yellow River Basin.However,little is known about how vegetation on the LP will respond to climate change and what is the sustainable threshold level of vegetation cover on the LP.Here we show that the temperature on the LP has risen 0.27°C per decade over the past 50 years,a rate that is 30%higher than the average warming rate across China.During historical times,vegetation change was regulated by environmental factors and anthropogenic activities.Vegetation coverage was about 53%on the LP from the Xia Dynasty to the Spring and Autumn and Warring States period.Over the past 70 years,however,the environment has gradually improved and the vegetation cover had increased to∼65%by 2021.We forecast future changes of vegetation cover on the LP in 2030s,in 2050s and in 2070s using SDM(Species Distribution Model)under Low-emission scenarios,Medium-emission scenarios and High-emission scenarios.An average value of vegetation cover under the three emission scenarios will be 64.67%,62.70%and 61.47%,respectively.According to the historical record and SDM forecasts,the threshold level of vegetation cover on the LP is estimated to be 53-65%.Currently,vegetation cover on the LP has increased to the upper limit of the threshold value(∼65%).We conclude that the risk of ecosystem collapse on the LP will increase with further temperature increases once the vegetated area and density exceed the threshold value.It is urgent to adopt sustainable strategies such as stopping expanding vegetation area and scientifically optimizing the vegetation structure on the LP to improve the ecological sustainability of the Yellow River Basin.展开更多
Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming...Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming complexes of calcium carbonate and calcium citrate in water.CCCGs were compared to a kind of commonly?used calcium carbonate preparation(CC)in the market in 5-week-old mice that had been treated with omeprazole,to suppress gastric acid secretion,and in untreated control mice.The results showed that:(1)CCCGs had better water solubility than CC in vitro;(2)In control mice,calcium absorption rates after CCCGs administration were comparable to those after CC administration;(3)Inhibition of gastric acid secretion did not affect calcium absorption after CCCGs,but moderately decreased it after CC;(4)The presence of phytic acid or tannin did not affect calcium absorption rates after CCCGs but did for CC;and(5)In nonnal mice,CCCGs did not inhibit gastric emptying and intestinal propulsion,and did not alter the gastrointestinal honnones.The results suggest that CCCGs may be therapeutically advantageous over more commonly used calcium supplement formulations,particularly for adolescents,because of their stable calcium absorption characteristics and their relatively favorable adverse effect profile.展开更多
Rubbers or elastomers play an important role in hi-tech technology and civilian daily life because of their unique and strategical properties.Generally,the rubber additives are essential components for rubbers’practi...Rubbers or elastomers play an important role in hi-tech technology and civilian daily life because of their unique and strategical properties.Generally,the rubber additives are essential components for rubbers’practical application.Nowadays,developing novel multifunctional additives has attracted increasing research attention.In this work,low-cost crude carbon dots(CCDs)were used as multifunctional additives for natural rubber/silica system(without any additional modification)through industrial compatible melt-mixing method.The results revealed that the CCDs could disperse well in the NR/silica system,and they could not only endow the rubber compound with excellent anti-aging capability due to CCDs’radical scavenging activity because of their plenty of nitrogen-containing species,but also improve the curing rate and mechanical performance of the rubber composite.Also,the CCDs could reduce the rolling resistance of the rubber composites(tanδvalue at 7%strain of the rubber composite could be decreased by 34%),which is promising for the application of energy-saving tire industry.Lastly,the addition of CCDs could effectively reduce the ZnO dosage by at least 40%in the rubber composite without deteriorating its performance.Overall,this work provides valuable guidance to develop novel cheap yet effective additives for the elastomer.展开更多
Background Hand, foot, and mouth disease (HFMD) is a common infectious disease in childhood caused by an enterovirus (EV), and which is principally seen in children under 5 years of age. To promote diagnostic awarenes...Background Hand, foot, and mouth disease (HFMD) is a common infectious disease in childhood caused by an enterovirus (EV), and which is principally seen in children under 5 years of age. To promote diagnostic awareness and effective treat-ments, to further standardize and strengthen the clinical management and to reduce the mortality of HFMD, the guidelines for diagnosis and treatment have been developed. Methods National Health Commission of China assembled an expert committee for a revision of the guidelines. The com-mittee included 33 members who are specialized in diagnosis and treatment of HFMD. Results Early recognition of severe cases is utmost important in diagnosis and treatment of patients with HFMD. The key to diagnosis and treatment of severe cases lies in the timely and accurate recognition of stages 2 and 3 of HFMD, in order to stop progression to stage 4. Clinicians should particularly pay attention to those EV-A71 cases in children aged less than 3 years, and those with disease duration less than 3 days. The following indicators should alert the clinician of possible deterioration and impending critical disease: (1) persistent hyperthermia;(2) involvement of nervous system;(3) worsening respiratory rate and rhythm;(4) circulatory dysfunction;(5) elevated peripheral WBC count;(6) elevated blood glucose and (7) elevated blood lactic acid. For treatment, most mild cases can be treated as outpatients. Patients should be isolated to avoid cross-infection. Intense treatment modalities should be given for those severe cases. Conclusion The guidelines can provide systematic guidance on the diagnosis and management of HFMD.展开更多
To the Editor:Membranous nephropathy(MN)is an autoimmune disease and accounts for the most common cause of nephrotic syndrome in adults.In China,the incidence of MN is estimated at approximately 12/million per year,wi...To the Editor:Membranous nephropathy(MN)is an autoimmune disease and accounts for the most common cause of nephrotic syndrome in adults.In China,the incidence of MN is estimated at approximately 12/million per year,with a mean age between 50 and 60 years and a 2:1 male predominance.MN(29.1%)was the most common pathological disease in a 10-year renal biopsy analysis.[1]In 2019,the Kidney Diseases:Improving Global Outcomes(KDIGO)guidelines recognized anti-phospholipase A2 receptor(anti-PLA2R)autoantibodies as a valuable molecular risk factor for the pejorative evolution of kidney function and recommended monitoring them for the diagnosis and assessment of MN immune activity.Assessing circulating anti-PLA2R autoantibodies may help in monitoring disease activity and guiding personalized therapy in patients with primary MN.展开更多
A Keggin-type polyoxomolybdate[H2biim]{Ni（biim）3（SiMO12O40）}[biim =1H,1＇H-[2,2＇]biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-ind...A Keggin-type polyoxomolybdate[H2biim]{Ni（biim）3（SiMO12O40）}[biim =1H,1＇H-[2,2＇]biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-induced and magnetism-induced 2D infrared correlation spectroscopy（2D-IR COS）and UV-vis DRS in order to explore the relationship between structure and properties.Temperatureinduced 2D-IR COS spectroscopy indicates that the terminal Mo-Oμ/υbonds are more sensitive than the bridging Mo=Ot,bands to temperature variation,which is in agreement with the conclusion of temperature-dependent IR.Magnetism-dependent 2D-IR COS spectroscopy reveals the stretching vibration of the Mo=Ot,occurs prior to the stretching vibration of the Mo-Oμ/υ,which is due to the coordination environment and the valence of the Si atom.The stability of compound 1 is investigated via TG and temperature-dependent IR.In RhB degradation,compound 1 shows good photocatalytic abilities.展开更多
The giant panda(Ailuropoda melanoleuca)is recognized worldwide as an icon for wildlife conservation.Since the introduction in 1992 of reliable methods for artificial insemination,the population of captive pandas has g...The giant panda(Ailuropoda melanoleuca)is recognized worldwide as an icon for wildlife conservation.Since the introduction in 1992 of reliable methods for artificial insemination,the population of captive pandas has grown to approximately 350 individuals in 2013.However,ca ptive panda populations are harmed by environmental pollution,diseases trans-mitted from domestic animals,and other anthropologenic activities.Although the Chinese government has proposed the creation of a Giant Panda National Park,there are at least three reasons that suggest that it is premature to reintroduce captive pandas into this proposed national park.First,habitat fragmentation remains the greatest threat to survival of giant pandas;second,most captive pandas are hybrids of the Sichuan and Qinling subspecies and release of hybrids may lead to further introgression between the two subspecies;and third,captive pandas may be competitively inferior to wild pandas in the region,and may not survive fights for food or mates.As an alternative,we suggest establishing a special con-servation zone in the Shennongjia National Nature Reserve for wild training of captive pandas prior to their reintroduction into the National Park.展开更多
基金The National Natural Science Foundation of China(42041005,U2243225)supports this research.
文摘Global temperatures will continue to increase in the future.The∼640,000-km2 Loess Plateau(LP)is a typical arid and semi-arid region in China.Similar regions cover∼41%of the Earth,and its soils are some of the most severely eroded anywhere in the world.It is very important to understand the vegetation change and its ecological threshold under climate change on the LP for the sustainable development in the Yellow River Basin.However,little is known about how vegetation on the LP will respond to climate change and what is the sustainable threshold level of vegetation cover on the LP.Here we show that the temperature on the LP has risen 0.27°C per decade over the past 50 years,a rate that is 30%higher than the average warming rate across China.During historical times,vegetation change was regulated by environmental factors and anthropogenic activities.Vegetation coverage was about 53%on the LP from the Xia Dynasty to the Spring and Autumn and Warring States period.Over the past 70 years,however,the environment has gradually improved and the vegetation cover had increased to∼65%by 2021.We forecast future changes of vegetation cover on the LP in 2030s,in 2050s and in 2070s using SDM(Species Distribution Model)under Low-emission scenarios,Medium-emission scenarios and High-emission scenarios.An average value of vegetation cover under the three emission scenarios will be 64.67%,62.70%and 61.47%,respectively.According to the historical record and SDM forecasts,the threshold level of vegetation cover on the LP is estimated to be 53-65%.Currently,vegetation cover on the LP has increased to the upper limit of the threshold value(∼65%).We conclude that the risk of ecosystem collapse on the LP will increase with further temperature increases once the vegetated area and density exceed the threshold value.It is urgent to adopt sustainable strategies such as stopping expanding vegetation area and scientifically optimizing the vegetation structure on the LP to improve the ecological sustainability of the Yellow River Basin.
文摘Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming complexes of calcium carbonate and calcium citrate in water.CCCGs were compared to a kind of commonly?used calcium carbonate preparation(CC)in the market in 5-week-old mice that had been treated with omeprazole,to suppress gastric acid secretion,and in untreated control mice.The results showed that:(1)CCCGs had better water solubility than CC in vitro;(2)In control mice,calcium absorption rates after CCCGs administration were comparable to those after CC administration;(3)Inhibition of gastric acid secretion did not affect calcium absorption after CCCGs,but moderately decreased it after CC;(4)The presence of phytic acid or tannin did not affect calcium absorption rates after CCCGs but did for CC;and(5)In nonnal mice,CCCGs did not inhibit gastric emptying and intestinal propulsion,and did not alter the gastrointestinal honnones.The results suggest that CCCGs may be therapeutically advantageous over more commonly used calcium supplement formulations,particularly for adolescents,because of their stable calcium absorption characteristics and their relatively favorable adverse effect profile.
基金supported by the National Natural Science Foundation of China(Nos.52103065,51988102 and 52273003)the scientific research fund of Wuhan Institute of Technology(No.K2021044).
文摘Rubbers or elastomers play an important role in hi-tech technology and civilian daily life because of their unique and strategical properties.Generally,the rubber additives are essential components for rubbers’practical application.Nowadays,developing novel multifunctional additives has attracted increasing research attention.In this work,low-cost crude carbon dots(CCDs)were used as multifunctional additives for natural rubber/silica system(without any additional modification)through industrial compatible melt-mixing method.The results revealed that the CCDs could disperse well in the NR/silica system,and they could not only endow the rubber compound with excellent anti-aging capability due to CCDs’radical scavenging activity because of their plenty of nitrogen-containing species,but also improve the curing rate and mechanical performance of the rubber composite.Also,the CCDs could reduce the rolling resistance of the rubber composites(tanδvalue at 7%strain of the rubber composite could be decreased by 34%),which is promising for the application of energy-saving tire industry.Lastly,the addition of CCDs could effectively reduce the ZnO dosage by at least 40%in the rubber composite without deteriorating its performance.Overall,this work provides valuable guidance to develop novel cheap yet effective additives for the elastomer.
文摘Background Hand, foot, and mouth disease (HFMD) is a common infectious disease in childhood caused by an enterovirus (EV), and which is principally seen in children under 5 years of age. To promote diagnostic awareness and effective treat-ments, to further standardize and strengthen the clinical management and to reduce the mortality of HFMD, the guidelines for diagnosis and treatment have been developed. Methods National Health Commission of China assembled an expert committee for a revision of the guidelines. The com-mittee included 33 members who are specialized in diagnosis and treatment of HFMD. Results Early recognition of severe cases is utmost important in diagnosis and treatment of patients with HFMD. The key to diagnosis and treatment of severe cases lies in the timely and accurate recognition of stages 2 and 3 of HFMD, in order to stop progression to stage 4. Clinicians should particularly pay attention to those EV-A71 cases in children aged less than 3 years, and those with disease duration less than 3 days. The following indicators should alert the clinician of possible deterioration and impending critical disease: (1) persistent hyperthermia;(2) involvement of nervous system;(3) worsening respiratory rate and rhythm;(4) circulatory dysfunction;(5) elevated peripheral WBC count;(6) elevated blood glucose and (7) elevated blood lactic acid. For treatment, most mild cases can be treated as outpatients. Patients should be isolated to avoid cross-infection. Intense treatment modalities should be given for those severe cases. Conclusion The guidelines can provide systematic guidance on the diagnosis and management of HFMD.
基金supported by grants from the“3-Year Action Plan of Shanghai to Further Speed Up the Development of Traditional Chinese Medicine”(Nos.ZY[2018-2020]-FWTX-6025,ZY[2018-2020]-ZYBZ-02).
文摘To the Editor:Membranous nephropathy(MN)is an autoimmune disease and accounts for the most common cause of nephrotic syndrome in adults.In China,the incidence of MN is estimated at approximately 12/million per year,with a mean age between 50 and 60 years and a 2:1 male predominance.MN(29.1%)was the most common pathological disease in a 10-year renal biopsy analysis.[1]In 2019,the Kidney Diseases:Improving Global Outcomes(KDIGO)guidelines recognized anti-phospholipase A2 receptor(anti-PLA2R)autoantibodies as a valuable molecular risk factor for the pejorative evolution of kidney function and recommended monitoring them for the diagnosis and assessment of MN immune activity.Assessing circulating anti-PLA2R autoantibodies may help in monitoring disease activity and guiding personalized therapy in patients with primary MN.
基金financially supported by the National Natural Science Foundation of China(No.51373003)Beijing Natural Science Foundation(No.2122059)Open Fund of State Key Laboratory of Structural Chemistry(No.20130015) and Science
文摘A Keggin-type polyoxomolybdate[H2biim]{Ni（biim）3（SiMO12O40）}[biim =1H,1＇H-[2,2＇]biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-induced and magnetism-induced 2D infrared correlation spectroscopy（2D-IR COS）and UV-vis DRS in order to explore the relationship between structure and properties.Temperatureinduced 2D-IR COS spectroscopy indicates that the terminal Mo-Oμ/υbonds are more sensitive than the bridging Mo=Ot,bands to temperature variation,which is in agreement with the conclusion of temperature-dependent IR.Magnetism-dependent 2D-IR COS spectroscopy reveals the stretching vibration of the Mo=Ot,occurs prior to the stretching vibration of the Mo-Oμ/υ,which is due to the coordination environment and the valence of the Si atom.The stability of compound 1 is investigated via TG and temperature-dependent IR.In RhB degradation,compound 1 shows good photocatalytic abilities.
文摘The giant panda(Ailuropoda melanoleuca)is recognized worldwide as an icon for wildlife conservation.Since the introduction in 1992 of reliable methods for artificial insemination,the population of captive pandas has grown to approximately 350 individuals in 2013.However,ca ptive panda populations are harmed by environmental pollution,diseases trans-mitted from domestic animals,and other anthropologenic activities.Although the Chinese government has proposed the creation of a Giant Panda National Park,there are at least three reasons that suggest that it is premature to reintroduce captive pandas into this proposed national park.First,habitat fragmentation remains the greatest threat to survival of giant pandas;second,most captive pandas are hybrids of the Sichuan and Qinling subspecies and release of hybrids may lead to further introgression between the two subspecies;and third,captive pandas may be competitively inferior to wild pandas in the region,and may not survive fights for food or mates.As an alternative,we suggest establishing a special con-servation zone in the Shennongjia National Nature Reserve for wild training of captive pandas prior to their reintroduction into the National Park.
