Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)forests.However,the specific ways in which their growth is affected by warm temperatures and drought remain...Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)forests.However,the specific ways in which their growth is affected by warm temperatures and drought remain unclear.To address this issue,60 and 62 tree-ring cores of B.platyphylla and B.costata were collected in Yichun,China.Using dendrochronological methods,the response and adaptation of these species to climate change were examined.A“hysteresis effect”was found in the rings of both species,linked to May–September moisture conditions of the previous year.Radial growth of B.costata was positively correlated with the standardized precipitation-evapotranspiration index(SPEI),the precipitation from September to October of the previous year,and the relative humidity in October of the previous year.Growth of B.costata is primarily restricted by moisture conditions from September to October.In contrast,B.platyphylla growth is mainly limited by minimum temperatures in May–June of both the previous and current years.After droughts,B.platyphylla had a faster recovery rate compared to B.costata.In the context of rising temperatures since 1980,the correlation between B.platyphylla growth and monthly SPEI became positive and strengthened over time,while the growth of B.costata showed no conspicuous change.Our findings suggest that the growth of B.platyphylla is already affected by warming temperatures,whereas B.costata may become limited if warming continues or intensifies.Climate change could disrupt the succession of these species,possibly accelerating the succession of pioneer species.The results of this research are of great significance for understanding how the growth changes of birch species under warming and drying conditions,and contribute to understanding the structural adaptation of mixed broadleaved-Korean pine(Pinus koraiensis)forests under climate change.展开更多
Dear Editor,Timely and effective hemostasis is of great significance for reducing body damage and mortality of patients [1]. Alginate is generally considered to be an excellent hemostatic polymer-based biomaterial and...Dear Editor,Timely and effective hemostasis is of great significance for reducing body damage and mortality of patients [1]. Alginate is generally considered to be an excellent hemostatic polymer-based biomaterial and has been approved by the Food and Drug Administration as Generally Recognized as Safe [2]. However, the violent crosslinking reaction and unstable structure at the wound site limit its clinical applications. Hence, we report a biocompatible and injectable composite hydrogel methacrylate alginate (Alg-AEMA)-based Eosin Y/N-phenylglycine (NPG)-initiated composite hydrogel (AEC) composed of photocrosslinkable alginate, viscosity modifiers and novel white light photoinitiator, namely Eosin Y/NPG system, for instant hemorrhage control.展开更多
针对NOMA-VLC系统中固定功率分配(Fixed Power Allocation,FPA)方法存在用户间干扰严重问题导致通信可靠性差,迭代注水功率分配(Iterative Water-filling Power Allocation,IWPA)方法存在难以保证用户公平性问题,提出基于信道容量的功...针对NOMA-VLC系统中固定功率分配(Fixed Power Allocation,FPA)方法存在用户间干扰严重问题导致通信可靠性差,迭代注水功率分配(Iterative Water-filling Power Allocation,IWPA)方法存在难以保证用户公平性问题,提出基于信道容量的功率分配方法,首先对多用户场景下的系统模型进行分析;在此基础上,基于迭代优化的方式进行发送端用户功率分配,达到信道容量的目标函数,保证系统可靠性和用户公平性;最后建立实验平台,通过蒙特卡洛实验对系统性能进行分析,实验结果表明:在三种不同的调制格式下,文中方法相较于FPA方法系统平均获得10 dB以上性能增益,相较于IWPA方法系统保证两用户可靠通信;随着前端调制阶次的提高,文中方法有效降低SNR需求,减小用户间的性能差异,使用户公平性得到良好保证。展开更多
基金the Key Project of the China National Key Research and Development Program(2021YFD2200401)the National Natural Science Foundation of China(42177421 and 41877426)。
文摘Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)forests.However,the specific ways in which their growth is affected by warm temperatures and drought remain unclear.To address this issue,60 and 62 tree-ring cores of B.platyphylla and B.costata were collected in Yichun,China.Using dendrochronological methods,the response and adaptation of these species to climate change were examined.A“hysteresis effect”was found in the rings of both species,linked to May–September moisture conditions of the previous year.Radial growth of B.costata was positively correlated with the standardized precipitation-evapotranspiration index(SPEI),the precipitation from September to October of the previous year,and the relative humidity in October of the previous year.Growth of B.costata is primarily restricted by moisture conditions from September to October.In contrast,B.platyphylla growth is mainly limited by minimum temperatures in May–June of both the previous and current years.After droughts,B.platyphylla had a faster recovery rate compared to B.costata.In the context of rising temperatures since 1980,the correlation between B.platyphylla growth and monthly SPEI became positive and strengthened over time,while the growth of B.costata showed no conspicuous change.Our findings suggest that the growth of B.platyphylla is already affected by warming temperatures,whereas B.costata may become limited if warming continues or intensifies.Climate change could disrupt the succession of these species,possibly accelerating the succession of pioneer species.The results of this research are of great significance for understanding how the growth changes of birch species under warming and drying conditions,and contribute to understanding the structural adaptation of mixed broadleaved-Korean pine(Pinus koraiensis)forests under climate change.
基金National Key Research and Development Program(2022YFA1104604,2017YFC1103303)Science Fund for National Defense Distinguished Young Scholars(2022-JCJQ-ZQ-016)+2 种基金National Nature Science Foundation of China(32000969,82002056,92268206)Military Medical Research Projects(145AKJ260015000X,2022-JCJQ-ZD-096-00)Key Support Program for Growth Factor Research(SZYZ-TR-03).
文摘Dear Editor,Timely and effective hemostasis is of great significance for reducing body damage and mortality of patients [1]. Alginate is generally considered to be an excellent hemostatic polymer-based biomaterial and has been approved by the Food and Drug Administration as Generally Recognized as Safe [2]. However, the violent crosslinking reaction and unstable structure at the wound site limit its clinical applications. Hence, we report a biocompatible and injectable composite hydrogel methacrylate alginate (Alg-AEMA)-based Eosin Y/N-phenylglycine (NPG)-initiated composite hydrogel (AEC) composed of photocrosslinkable alginate, viscosity modifiers and novel white light photoinitiator, namely Eosin Y/NPG system, for instant hemorrhage control.
文摘针对NOMA-VLC系统中固定功率分配(Fixed Power Allocation,FPA)方法存在用户间干扰严重问题导致通信可靠性差,迭代注水功率分配(Iterative Water-filling Power Allocation,IWPA)方法存在难以保证用户公平性问题,提出基于信道容量的功率分配方法,首先对多用户场景下的系统模型进行分析;在此基础上,基于迭代优化的方式进行发送端用户功率分配,达到信道容量的目标函数,保证系统可靠性和用户公平性;最后建立实验平台,通过蒙特卡洛实验对系统性能进行分析,实验结果表明:在三种不同的调制格式下,文中方法相较于FPA方法系统平均获得10 dB以上性能增益,相较于IWPA方法系统保证两用户可靠通信;随着前端调制阶次的提高,文中方法有效降低SNR需求,减小用户间的性能差异,使用户公平性得到良好保证。
