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1A new algorithm for fast mining frequent itemsets using N-lists显示文摘Mining frequent itemsets has emerged as a fundamental problem in data mining and plays an essential role in many important data mining tasks.In this paper,we propose a novel vertical data representation called N-list,which originates from an FP-tree-like coding prefix tree called PPC-tree that stores crucial information about frequent itemsets.Based on the N-list data structure,we develop an efficient mining algorithm,PrePost,for mining all frequent itemsets.Efficiency of PrePost is achieved by the following three reasons.First,N-list is compact since transactions with common prefixes share the same nodes of the PPC-tree.Second,the counting of itemsets' supports is transformed into the intersection of N-lists and the complexity of intersecting two N-lists can be reduced to O(m + n) by an efficient strategy,where m and n are the cardinalities of the two N-lists respectively.Third,PrePost can directly find frequent itemsets without generating candidate itemsets in some cases by making use of the single path property of N-list.We have experimentally evaluated PrePost against four state-of-the-art algorithms for mining frequent itemsets on a variety of real and synthetic datasets.The experimental results show that the PrePost algorithm is the fastest in most cases.Even though the algorithm consumes more memory when the datasets are sparse,it is still the fastest one.DENG ZhiHong WANG ZhongHui JIANG JiaJian 2012Science China(Information Sciences)2012,55,9:23
2Autologous transplantation of bone marrow mesenchymal stem cells on diabetic patients with lower limb ischemia显示文摘学习骨头髓的自体同源的移植的功效和安全的目的有更低的手足局部缺血的糖尿病的病人上的间充质的干细胞。有更低的手足局部缺血的五十种类型 2 糖尿病的病人被注册并且使随机化到也的方法移植了组或控制组。病人在两个都,组接受了一样的常规治疗。同时,从每个移植病人的 20 ml 骨头髓被收集,并且间充质的干细胞被密度坡度 centrifugation 分开并且在有自体同源的浆液的媒介有教养。在在 vitro 的三星期的支持者文化以后, 7.32 ????????????????? 金 ???????????? ㈠ ?????? ┷?Lu Debin Jiang Youzhao Liang Ziwen Li Xiaoyan Zhang Zhonghui Chen Bing 2008Journal of Medical Colleges of PLA(China)2008,23,2:16
3Energy dissipation of coal and rock during damage and failure process based on EMR显示文摘The physical and mechanical change processes of coal and rock are closely related to energy transformation,and the destruction and failure of coal and rock is an instability phenomena driven by energy change.However,the energy change of large-scale coal rock in the mine site is hardly calculated accurately,making it difficult to monitor coal-rock systematic failure and collapse from the perspective of energy.By the energy dissipation EMR monitoring system,we studied the damage and failure of coal and rock with bursting liability from the energy dissipation point using the geophysical method-EMR,and explored the energy dissipation characteristics during uniaxial compression and their main influencing factors.The results show that under displacement-control loading mode,there are 2 types of energy dissipation trends for both coal and rock with bursting liability.The type Ⅰ trend is a steady increase one during the whole process,therein,the energy dissipation of rock samples is accelerated at the peak load.The type Ⅱ trend energy is a W-shaped fluctuating one containing 6 stages.Under load-control loading mode,there is one energy dissipation trend of shock downward-steady rise.Besides that,rock samples also present a trend of 4 stages.The energy dissipation characteristics of coal and rockduring loading failure process can be used as effective criteria to assess whether they are in a stable or destructive stage.The factors influencing energy dissipation in the loading failure process of coal and rock mainly include strength,homogeneity,and energy input efficiency.Song Dazhao Wang Enyuan Li Zhonghui Liu Jie Xu Wenquan 2015International Journal of Mining Science and Technology2015,25,5:16
4Fractal characteristics of surface crack evolution in the process of gas-containing coal extrusion显示文摘In this paper, simulated experiment device of coal and gas outburst was employed to perform the experiment on gas-containing coal extrusion. In the experiment, coal surface cracks were observed with a high-speed camera and then the images were processed by sketch. Based on the above description, the paper studied the fractal dimension values from different positions of coal surface as well as their changing laws with time. The results show that there is a growing parabola trend of crack dimension value in the process of coal extrusion. Accordingly, we drew the conclusion that extruded coal crack evolution is a process of fractal dimension value increase. On the basis of fractal dimension values taken from different parts of coal masses, a fractal dimension of the contour map was drawn. Thus, it is clear that the contour map involves different crack fractal dimension values from different positions. To be specific, where there are complicated force and violent movement in coal mass, there are higher fractal dimension values, i.e., the further the middle of observation surface is from the exit of coal mass, and the lower the fractal dimension value is. In line with fractal geometry and energy theory of coal and gas outburst, this study presents the relation between fractal dimension and energy in the process of extruding. In conclusion, the evolution of crack fractal dimension value can signify that of energy, which has laid a solid foundation for the quantification research on the mechanism of gas-containing coal extrusion.Chen Peng Wang Enyuan Ou Jianchun Li Zhonghui Wei Mingyao Li Xuelong 2013International Journal of Mining Science and Technology2013,23,1:12
5Solar influenced late Holocene temperature changes on the northern Tibetan Plateau显示文摘Considerable efforts have been made to extend temperature records beyond the instrumental period through proxy reconstructions,in order to further understand the mechanisms of past climate variability.Yet,the global coverage of existing temperature records is still limited,especially for some key regions like the Tibetan Plateau and for earlier times including the Medieval Warm Period(MWP).Here we present decadally-resolved,alkenone-based,temperature records from two lakes on the northern Tibetan Plateau.Characterized by marked temperature variability,our records provide evidence that temperatures during the MWP were slightly higher than the modern period in this region.Further,our temperature reconstructions,within age uncertainty,can be well correlated with solar irradiance changes,suggesting a possible link between solar forcing and natural climate variability,at least on the northern Tibetan Plateau.HE YuXin LIU WeiGuo ZHAO Cheng WANG Zheng WANG HuanYe LIU Yi QIN XianYan HU QiHou AN ZhiSheng LIU ZhongHui 2013Chinese Science Bulletin2013,58,9:11
6Abundance of antibiotic resistance genes and their association with bacterial communities in activated sludge of wastewater treatment plants: Geographical distribution and network analysis显示文摘Wastewater treatment plants(WWTPs) are deemed reservoirs of antibiotic resistance genes(ARGs). Bacterial phylogeny can shape the resistome in activated sludge. However, the co-occurrence and interaction of ARGs abundance and bacterial communities in different WWTPs located at continental scales are still not comprehensively understood. Here, we applied quantitative PCR and Miseq sequence approaches to unveil the changing profiles of ARGs(sul1, sul2, tet W, tet Q, tet X), int I1 gene, and bacterial communities in 18 geographically distributed WWTPs. The results showed that the average relative abundance of sul1 and sul2 genes were 2.08 × 10^(-1) and 1.32 × 10^(-1) copies/16 S rRNA copies, respectively. The abundance of tet W gene was positively correlated with the Shannon diversity index(H′), while both studied sul genes had significant positive relationship with the int I1 gene. The highest average relative abundances of sul1, sul2, tet X, and int I1 genes were found in south region and oxidation ditch system. Network analysis found that 16 bacterial genera co-occurred with tet W gene. Co-occurrence patterns were revealed distinct community interactions between aerobic/anoxic/aerobic and oxidation ditch systems. The redundancy analysis model plot of the bacterial community composition clearly demonstrated that the sludge samples were significant differences among those from the different geographical areas,and the shifts in bacterial community composition were correlated with ARGs. Together,these findings from the present study will highlight the potential risks of ARGs and bacterial populations carrying these ARGs, and enable the development of suitable technique to control the dissemination of ARGs from WWTPs into aquatic environments.Haihan Zhang Huiyan He Shengnan Chen Tinglin Huang Kuanyu Lu Zhonghui Zhang Rong Wang Xueyao Zhang Hailong Li 2019Journal of Environmental Sciences2019,31,8:9
7Evaluation of Cloud Top Height Retrievals from China’s Next-Generation Geostationary Meteorological Satellite FY-4A显示文摘To evaluate the validity of cloud top height (CTH) retrievals from FY-4A, the first of China's next-generation geostationary meteorological satellite series, the retrievals are compared to those from Himawari-8, CloudSat, Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), and Moderate Resolution Imaging Spectroradiometer (MODIS) operational products from August to October 2017. Regarding CTHs from CloudSat, CALIPSO, and MODIS as truth, the results show that the performance of FY-4A CTH retrievals is similar to that of Himawari-8. Both FY-4A and Himawari-8 retrieve reasonable CTH values for single-layer clouds, but perform poorly for multi-layer clouds. The mean bias error (MBE) shows that the mean value of FY-4A CTH retrievals is smaller than that of Himawari-8 for single-layer clouds but larger for multi-layer clouds. For ice crystal clouds, both FY-4A and Himawari-8 obtain the underestimated CTHs. However, there is a tendency for FY-4A and Himawari-8 to overestimate the CTH values of CloudSat and CALIPSO mainly for low level liquid water clouds. The temperature inversion near the tops of water clouds may result in an overestimation of CTHs. According to the MBE change with altitude, FY-4A and Himawari-8 overestimate the CTHs mainly for clouds below 3 km, and the overestimation is slightly more apparent in Himawari-8 data than that in FY-4A values. As the cloud optical thickness (COT) increases, the CTH bias of FY-4A CTH retrievals gradually decreases. Two typical cases are analyzed to illustrate the differences between different satellites' CTH retrievals in detail.Zhonghui TAN Shuo MA Xianbin ZHAO Wei YAN Wen LU 2019Journal of Meteorological Research2019,33,3:8
8Preliminary analysis of spatiotemporal pattern of global land surface water显示文摘Land surface water(LSW) is one of the most important resources for human survival and development, and it is also a main component of global water recycling. A full understanding of the spatial distribution of land surface water and a continuous measuring of its dynamics can support to diagnose the global ecosystem and environment. Based on the Global Land 30-water 2000 and Global Land 30-water 2010 products, this research analyzed the spatial distribution pattern and temporal fluctuation of land surface water under scale-levels of global, latitude and longitude, continents, and climate zones. The Global Land 30-water products were corrected the temporal inconsistency of original remotely sensed data using MODIS time-series data, and then calculated the indices such as water area, water ration and coefficient of spatial variation for further analysis. Results show that total water area of land surface is about 3.68 million km2(2010), and occupies 2.73% of land area. The spatial distribution of land surface water is extremely uneven and is gathered mainly in mid- to high-latitude area of the Northern Hemisphere and tropic area. The comparison of water ratio between 2000 and 2010 indicates the overall fluctuation is small but spatially differentiated. The Global Land 30-water products and the statistics provided the fundamental information for analyzing the spatial distribution pattern and temporal fluctuation of land surface water and diagnosing the global ecosystem and environment.CAO Xin CHEN Jun CHEN LiJun LIAO AnPing SUN FangDi LI Yang LI Lei LIN ZhongHui PANG ZhiGuo CHEN Jin HE ChaoYing PENG Shu 2014Science China Earth Sciences2014,57,10:8
9Electrochemical hydrogen storage characteristics of La_(0.75-x) M_xMg_(0.25)Ni_(3.2)Co_(0.2)Al_(0.1)(M=Zr,Pr;x=0,0.1) alloys prepared by melt spinning显示文摘In order to ameliorate the electrochemical hydrogen storage performances of La-Mg-Ni system A_2B_7-type electrode alloys, the partial substitution of M (M = Zr, Pr) for La was performed. The melt spinning technology was used to fabricate the La_(0.75-x)M_xMg_0.25Ni_3.2Co_0.2Al_0.1 (M = Zr, Pr; x = 0, 0.1) electrode alloys. The influences of the melt spinning and substituting La with M (M = Zr, Pr) on the structures and the electrochemical hydrogen storage characteristics of the alloys were investigated. The analysis of XRD, SEM, and TEM reveals that the as-cast and spun alloys have a multiphase structure composed of two main phases (La, Mg)_2Ni_7 and LaNi_5 as well as a residual phase LaNi_2 . The as-spun (M = Pr) alloy displays an entire nanocrystalline structure, while an amorphous-like structure is detected in the as-spun (M = Zr) alloy, implying that the substitution of Zr for La facilitates the amorphous formation. The electrochemical measurements exhibit that the substitution of Pr for La clearly increases the discharge capacity of the alloys; however, the Zr substitution brings on an adverse impact. Meanwhile, the M (M = Zr, Pr) substitution significantly enhances its cycle stability. The melt spinning exerts an evident effect on the electrochemical performances of the alloys, whose discharge capacity and high rate discharge ability (HRD) first mount up and then fall with the growing spinning rate, whereas their cycle stabilities monotonously augment as the spinningZHANG Yanghuan YANG Tai CAI Ying HOU Zhonghui REN Huiping ZHAO Dongliang 2012Rare Metals2012,31,5:7
10DRAGON-Lab―Next generation internet technology experiment platform显示文摘Testbed technology is very important in the development of the Internet. Similar to the present internet,next generation internet also starts from testbed. There are two kinds of testbeds,testbed networks like CNGI-CERNET2,Internet2,Geant;testbed systems like PlanetLab,NS2. DRAGON-Lab can be viewed as both testbed network and testbed system. DRAGON-Lab is an independent AS(autonomous system) and connected to multiple real networks. On the other hand,DRAGON-Lab integrates many resources of its own,partners' and internet's,so as to provide open service. DRAGON-Lab has a large scale,provides open service,supports remote visualized experiments and programmable experiments. More details will be introduced in this paper.WANG JiLong LI ZhongHui LV GuoHan JIANG CaiPing LI Xing ZHANG QianLi 2008Science in China(Series F)2008,51,11:6
11Exosomal LINC00355 derived from cancer-associated fibroblasts promotes bladder cancer cell resistance to cisplatin by regulating miR-34b-5p/ABCB1 axis显示文摘Cisplatin resistance is a major challenge for bladder cancer(BC).Evidence indicates that exosome derived from cancer-associated fibroblasts(CAF-Exo)can promote chemotherapy resistance in various human tumors by delivering bioactive molecules.We have previously demonstrated that CAF-derived exosomal LINC00355 promotes BC cell proliferation and invasion.However,the underlying mechanisms are still unclear.In this study,we aimed to investigate the role and mechanisms of CAF-derived exosomal LINC00355 in BC cell resistance to cisplatin.Exosomes were isolated from normal fibroblasts(NFs)and BC tumor-derived CAFs,namely,NF-Exo and CAF-Exo.CAFs were transfected with si-Ctrl or si-LINC00355 and then different exosomes were isolated,namely,CAF^(si-Ctrl)-Exo and CAF^(si-LINC00355)-Exo.The human BC cell lines(T24 and 5367)were incubated with NF-Exo,CAF-Exo,CAF^(si-Ctrl)-Exo,and CAF^(si-LINC00355)-Exo in the presence of cisplatin.MTT proliferation assay and flow cytometric analysis showed that CAF-Exo promoted BC cell resistance to cisplatin and upregulated ABCB1 expression in BC cells by transferring LINC00355 to BC cells.Luciferase activity assay confirmed the interaction between miR-34b-5p and LINC00355 or ABCB1.qRT-PCR and western blot analysis further showed that LINC00355 sponged miR-34b-5p to upregulate ABCB1 expression.However,the promoting effects of CAF-Exo on BC cell resistance to cisplatin were abolished by miR-34b-5p overexpression and ABCB1 silencing.In conclusion,exosomal LINC00355 derived from CAFs promotes BC cell resistance to cisplatin by regulating the miR-34b-5p/ABCB1 axis.Guangyue Luo Yangyang Zhang Zhonghui Wu Ligang Zhang Chaozhao Liang Xianguo Chen 2021Acta Biochimica et Biophysica Sinica2021,53,5:6
12Rational design of novel ultra-small amorphous Fe_(2)O_(3)nanodots/graphene heterostructures for all-solid-state asymmetric supercapacitors显示文摘Constructing graphene-based heterostructures with large interfacial area is an efficient approach to enhance the electrochemical performance of supercapacitors but remains great challenges in their synthesis.Herein,a novel ultra-small amorphous Fe_(2)O_(3)nanodots/graphene heterostructure(a-Fe_(2)O_(3)NDs/RGO)aerogel was facilely synthesized via excessive metal-ion-induced self-assembly and subsequent calcination route using Prussian blue/graphene oxide(PB/GO)composite aerogel as precursors.The deliberately designed a-Fe_(2)O_(3)NDs/RGO heterostructure offers a highly interconnected porous conductive network,large heterostructure interfacial area,and plenty of accessible active sites,greatly facilitating the electron transfer,electrolyte diffusion,and pseudocapacitive reactions.The obtained a-Fe_(2)O_(3)NDs/RGO aerogel could be used as flexible free-standing electrodes after mechanical compression,which exhibited a significantly enhanced specific capacitance of 347.4 F·g^(-1)at 1 A·g^(-1),extraordinary rate capability of 184 F·g^(-1)at 10 A·g^(-1),and decent cycling stability.With the as-prepared a-Fe_(2)O_(3)NDs/RGO as negative electrodes and the Co_(3)O_(4)NDs/RGO as positive electrodes,an all-solid-state asymmetric supercapacitor(a-Fe_(2)O_(3)NDs/RGO//Co_(3)O_(4)NDs/RGO asymmetric supercapacitor(ASC))was assembled,which delivered a high specific capacitance of 69.1 F·g^(-1)at 1 A·g^(-1)and an impressive energy density of 21.6 W·h·k·g^(-1)at 750 W·k·g^(-1),as well as good cycling stability with a capacity retention of 94.3%after 5,000 cycles.This work provides a promising avenue to design high-performance graphene-based composite electrodes and profound inspiration for developing advanced flexible energy-storage devices.Chenxiao Wu Zhifang Zhang Zhonghui Chen Zuimin Jiang Huiyu Li Haijing Cao Yongsheng Liu Yanyan Zhu Zebo Fang Xiangrong Yu 2021Nano Research2021,14,4:6
13Acoustic emission generated during the gas sorption-desorption process in coal显示文摘An experimental system for monitoring the acoustic signals generated in coal during gas sorption and/or desorption was designed and the acoustic signals were observed under different gas pressures. The experimental results show that signals generated by the coal during gas adsorption are attenuated over time. Also, the signals are not continuous but are impulsive. The intensity of the signals generated during gas desorption is far smaller than that observed during adsorption. The signal seen during desorption remains essentially stable. Cycles of sorption and desorption cause acoustic emission signals that exhibit a memory effect, which depends upon the maximum gas pressure the sample was exposed to in earlier cycles. Lower pressures in subsequent cycles, compared to the maximum adsorption pressure in previous cycles, cause both the energy and impulse frequency to be lower than previously. On the contrary, a gas adsorption pressure that exceeds the maximum pressure seen by the sample during earlier cycles causes both the energy and impulse frequency to be high.Ma Yankun Wang Enyuan Xiao Dong Li Zhonghui Liu Jie Gan Lijia 2012International Journal of Mining Science and Technology2012,22,3:5
14Mesenchymal stem cell treatment improves outcome of COVID-19 patients via multiple immunomodulatory mechanisms显示文摘The infusion of coronavirus disease 2019(COVID-19)patients with mesenchymal stem cells(MSCs)potentially improves clinical symptoms,but the underlying mechanism remains unclear.We conducted a randomized,single-blind,placebo-controlled(29 patients/group)phase II clinical trial to validate previous findings and explore the potential mechanisms.Patients treated with umbilical cord-derived MSCs exhibited a shorter hospital stay(P=0.0198)and less time required for symptoms remission(P=0.0194)than those who received placebo.Based on chest images,both severe and critical patients treated with MSCs showed improvement by day 7(P=0.0099)and day 21(P=0.0084).MSC-treated patients had fewer adverse events.MSC infusion reduced the levels of C-reactive protein,proinflammatory cytokines,and neutrophil extracellular traps(NETs)and promoted the maintenance of SARS-CoV-2-specific antibodies.To explore how MSCs modulate the immune system,we employed single-cell RNA sequencing analysis on peripheral blood.Our analysis identified a novel subpopulation of VNN2+hematopoietic stem/progenitorlike(HSPC-like)cells expressing CSF3R and PTPRE that were mobilized following MSC infusion.Genes encoding chemotaxis factors—CX3CR1 and L-selectin—were upregulated in various immune cells.MSC treatment also regulated B cell subsets and increased the expression of costimulatory CD28 in T cells in vivo and in vitro.In addition,an in vivo mouse study confirmed that MSCs suppressed NET release and reduced venous thrombosis by upregulating kindlin-3 signaling.Together,our results underscore the role of MSCs in improving COVID-19 patient outcomes via maintenance of immune homeostasis.Rongjia Zhu Tingdong Yan Yingmei Feng Yan Liu Hongcui Cao Gongxin Peng Yanlei Yang Zhen Xu Jingqi Liu Wei Hou Xiaoyue Wang Zhe Li Luchan Deng Shihua Wang Jing Li Qin Han Hongling Li Guangliang Shan Yinghao Cao Xingyan An Jianshe Yan Zhonghui Zhang Huafei Li Xuebin Qu Jiaqi Zhu Shumin Zhou Jiao Wang Fengchun Zhang Jinming Gao Ronghua Jin Dayong Xu Yan-Qing Ma Tao Huang Shuang Peng Zhi Zheng Ilia Stambler Eric Gilson Lee Wei Lim Alexey Moskalev Antonio Cano Sasanka Chakrabarti Brun Ulfhake Huanxing Su Haoying Xu Sihuan Xu Feng Wei Holly MBrown-Borg Kyung-Jin Min Georgina Ellison-Hughes Calogero Caruso Kunlin Jin Robert Chunhua Zhao 2021Cell Research2021,31,12:5
15Cloning of the full-length gene of activin receptor-interacting protein2a and characterization of its interaction with ActR Ⅱ A显示文摘为了调查细胞内部的信号 transduction 的机制,由 activin 受体调停了,编码新奇 activin 的全身的基因交往受体的 protein2a (ARIP2a ) 从一个老鼠大脑 cDNA 图书馆被识别。ARIP2a 和 ARIP2 和在导致 activin 的 RAW264 的 ARIP2 的序列。7 房间被比较,并且在 ARIP2a 和 ActRIIA 之间的相互作用被证实。序列分析表明除了 99 th 氨基酸。RT-PCR 试金证明 ARIP2a mRNA 高度在大脑,垂体和睾丸被表示,并且中等在胰和卵巢,但是在另外的纸巾无法发现。而, ARIP2 mRNA 广泛地在我们测试了的所有老鼠纸巾被散布。而且, ARIP2a mRNA 的表示显著地在刺激 activin 的 RAW264 被减少。7 个房间;然而, ARIP2 mRNA 的表示被增加。另外,在 ARIP2a 之间的相互作用和 activin 类型 IIA 受体(ActRIIA ) 被哺乳动物的二混血儿的试金和下拉试金进一步表明。总起来说,那些结果显示尽管 ARIP2a 对 ARIP2 相应,他们在到 activin 的织物分发和回答是不同的。ARIP2a 能也与 activin 类型 II 受体(ActRIIA ) 交往被哺乳动物的 two-hybird 试金和下拉试金进一步表明。总起来说,那些结果显示尽管 ARIP2a 对 ARIP2 相应,他们在到 activin 的织物分发和回答是不同的。ARIP2a 能也作为 ARIP 家庭的一篇小说与 activin 类型 II 受体交往。CUI Xueling TAI Guixiang ZHANG Hongjun FANG Lin LIU Zhonghui 2007Progress in Natural Science:Materials International2007,17,2:5
16Study and application of monitoring plane displacement of a similarity model based on time-series images显示文摘In order to compensate for the deficiency of present methods of monitoring plane displacement in similarity model tests,such as inadequate real-time monitoring and more manual intervention,an effective monitoring method was proposed in this study,and the major steps of the monitoring method include:firstly,time-series images of the similarity model in the test were obtained by a camera,and secondly,measuring points marked as artificial targets were automatically tracked and recognized from time-series images.Finally,the real-time plane displacement field was calculated by the fixed magnification between objects and images under the specific conditions.And then the application device of the method was designed and tested.At the same time,a sub-pixel location method and a distortion error model were used to improve the measuring accuracy.The results indicate that this method may record the entire test,especially the detailed non-uniform deformation and sudden deformation.Compared with traditional methods this method has a number of advantages,such as greater measurement accuracy and reliability,less manual intervention,higher automation,strong practical properties,much more measurement information and so on.Xu Jiankun Wang Enyuan Li Zhonghui Wang Chao 2011Mining Science and Technology2011,21,4:5
17Estimating the productive potential of five natural forest types in northeastern China显示文摘Background: There is a serious lack of experience regarding the productive potential of the natural forests in northeastern China, which severely limits the development of sustainable forest management strategies for this most important forest region in China. Accordingly, the objective of this study is to develop a first comprehensive system for estimating the wood production for the five dominant forest types.Methods: Based on a network of 384 field plots and using the state-space approach, we develop a system of dynamic stand models, for each of the five main forest types. Four models were developed and evaluated, including a base model and three extended models which include the effects of dominant height and climate variables. The four models were fitted, and their predictive strengths were tested, using the 'seemingly unrelated regression'(SUR) technique.Results: All three of the extended models increased the accuracy of the predictions at varying degrees for the five major natural forest types of northeastern China. The inclusion of dominant height and two climate factors(precipitation and temperature) in the base model resulted in the best performance for all the forest types. On average, the root mean square values were reduced by 13.0% when compared with the base model.Conclusion: Both dominant height and climate factors were important variables in estimating forest production. This study not only presents a new method for estimating forest production for a large region, but also explains regional differences in the effect of site productivity and climate.Zhaofei Wu Zhonghui Zhang Juan Wang 2019Forest Ecosystems2019,6,4:5
18地球倾角驱动的末次冰期期间南亚地区变暖显示文摘当前对晚第四纪以来轨道尺度上地球气候变化的认识,主要包括高纬驱动的以~10万年周期为主的冰期-间冰期循环和夏季风影响的以~2.3万年周期为主的低纬水文变化.但是,由于低纬陆地没有较为可靠的温度记录,使得对低纬陆地的长期气候变化仍然缺乏全面的理解.本文通过获取云南腾冲青海的一根湖泊沉积岩芯,分析了沉积物中的支链甘油二烷基甘油四醚酯(brGDGTs)和叶蜡氢同位素,分别重建了~9万年以来南亚地区的年平均温度和季风降水的变化序列.结果表明,夏季风降水与之前的研究一致,表现出明显的2.3万年周期,但是年均温度记录揭示了8.8~7.1万年和4.5~2.2万年存在两个暖期,温度变幅2~3℃,与该记录中的冰期-间冰期变幅接近.通过对比TraCE21ka瞬态模拟结果和相关气候驱动因子,发现这两个暖期很可能受当地的年均太阳轨道辐射影响;而低纬地区的年均太阳辐射由以~4.1万年周期为主的地球倾角变化控制,并与高纬地区的年均太阳轨道辐射呈反向关系.此外,该记录中的两个暖期与古人类活动的年代有较强的相关性,表明末次冰期内温度变化可能对亚洲地区古人类的生存有重要的影响.赵成 Eelco J.Rohling Zhengyu Liu 杨小强 张恩楼 程军 Zhonghui Liu 安芷生 羊向东 冯小平 孙晓双 张灿 闫天龙 隆浩 晏宏 Zicheng Yuk 刘卫国 于世永 沈吉 2021Science Bulletin2021,66,11:5
19Activin A maintains cerebral cortex neuronal survival and increases voltage-gated Na^+ neuronal current显示文摘Activin A,which was first described in 1986,has been shown to maintain hippocampal neuronal survival.Activin A increases intracellular free Ca2+ via L-type Ca2+ channels.Our previous study showed that activin A promotes neurite growth of dorsal root ganglia in embryonic chickens and inhibits nitric oxide secretion.The present study demonstrated for the first time that activin A could maintain cerebral cortex neuronal survival in vitro for a long period,and that activin A was shown to increase voltage-gated Na+ current(INa) in Neuro-2a cells,which was recorded by patch clamp technique.The present study revealed a novel mechanism for activin A,as well as the influence of activin A on neurons by regulating expressions of vasoactive intestine peptide and inducible nitric oxide synthase.Jingyan Ge Yinan Wang Haiyan Liu Fangfang Chen Xueling Cui Zhonghui Liu 2010Neural Regeneration Research2010,5,19:4
20Direct Effects of Activin A on the Activation of Mouse Macrophage RAW264.7 Cells显示文摘Macrophages play critical roles in innate immune and acquired immune via secreting pro-inflammatory mediators, phagocytosing microorganisms and presenting antigens. Activin A, a member of transforming growth factor β (TGF-β) superfamily, is produced by macrophages and microglia cells. In this study, we reported a direct effect of activin A as a pro-inflammatory factor on mouse macrophage cell line RAW264.7 cells. Our data revealed that activin A could not only increase IL-1β and IL-6 production from RAW264.7 cells, but also promote pinocytic and phagocytic activities of RAW264.7 cells. In addition, activin A obviously up-regulated MHC II expression on the surface of RAW264.7 cells, whereas did not influence MHC I expression. Activin A also enhanced CD80 expression, which is a marker of activated macrophages, but did not influence RAW264.7 cell proliferation. These data suggest that activin A may regulate primary macrophage-mediated innate and acquired immune response via promoting the activation of rest macrophages.Jingyan Ge Yinan Wang Ye Feng Haiyan Liu Xueling Cui Guixiang Tai Zhonghui Liu 2009Cellular & Molecular Immunology2009,6,2:4
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