|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Zircon U-Pb age and Hf isotope of Quanyishang A-type granite in Yichang: Signification for the Yangtze continental cratonization in Paleoproterozoic显示文摘Zircon U-Pb age and Hf isotope, and major and trace element compositions were reported for granite at Quanyishang, which intruded into the Kongling complex in Yichang, Hubei Province. The results show that the Quanyishang granite is rich in silicon and alkalis but poor in calcium and magnesium, and displays enrichment in Ga, Y, Zr, Nb but depletion in Sr and Ba, exhibiting the post-orogenic A-type affinity. 90% zircons from the granite are concordant, and give a middle Paleoproterozoic magmatic crystallization age (mean 1854 Ma). Initial Hf isotope ratios (176Hf/177Hf)i of the middle Paleoproterozoic zircons range from 0.280863 to 0.281134 and they have negative εHf(t) values with a minimum of -26.3. These zircons give the depleted mantle model ages (TDM) of 2.9―3.3 Ga (mean 3.0 Ga), and the average crustal model ages (Tcrust) of 3.6―4.2 Ga (mean 3.8 Ga). A Mesoarchean grain with 207Pb/206Pb age of 2859 Ma has a slightly high TDM (3.4 Ga) but similar Tcrust (3.8 Ga) to the Paleoproterozoic zircons. All these data suggest that the source materials of the Quanyishang A-type granite are unusually old, at least ≥2.9 Ga (even Eoarchean). The event of crustal remelting, which resulted in the formation of the Quanyishang granite in the middle Paleoproterozoic, recorded the cratonization of the Yangtze conti- nent. The process may have relation to the extension and collapse of the deep crust with Archean ages, in response to the transition stage of the assembly and breakup of the Columbia supercontinent. | XIONG Qing HENG JianPing YU ChunMei SU YuPing TANG HuaYun ZHANG ZhiHai | 2009 | Chinese Science Bulletin2009，54，3： | 46 |
| 2 | Human Gut Microbiota and Gastrointestinal Cancer显示文摘Human gut microbiota play an essential role in both healthy and diseased states of humans.In the past decade,the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities,as well as the possible mechanisms through which the microbiota are involved in cancer prevention,carcinogenesis,and anti-cancer therapy.A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways.Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing in?ammation and immune dysregulation,which lead to genetic instability,but also interfere with the pharmacodynamics of anticancer agents.In this article,we mainly reviewed the in?uence of gut microbiota on cancers in the gastrointestinal(GI)tract(including esophageal,gastric,colorectal,liver,and pancreatic cancers)and the regulation of microbiota by diet,prebiotics,probiotics,synbiotics,antibiotics,or the Traditional Chinese Medicine.We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future.We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers,which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention,diagnosis,and treatment. | Changting Meng Chunmei Bai Thomas D. Brown Leroy E. Hood Qiang Tian | 2018 | Genomics, Proteomics & Bioinformatics2018，16，1： | 43 |
| 3 | Anisotropic coding metamaterials and their powerful manipulation of differently polarized terahertz waves显示文摘Metamaterials based on effective media can be used to produce a number of unusual physical properties(for example,negative refraction and invisibility cloaking)because they can be tailored with effective medium parameters that do not occur in nature.Recently,the use of coding metamaterials has been suggested for the control of electromagnetic waves through the design of coding sequences using digital elements‘0’and‘1,'which possess opposite phase responses.Here we propose the concept of an anisotropic coding metamaterial in which the coding behaviors in different directions are dependent on the polarization status of the electromagnetic waves.We experimentally demonstrate an ultrathin and flexible polarization-controlled anisotropic coding metasurface that functions in the terahertz regime using specially designed coding elements.By encoding the elements with elaborately designed coding sequences(both 1-bit and 2-bit sequences),the x-and y-polarized waves can be anomalously reflected or independently diffused in three dimensions.The simulated far-field scattering patterns and near-field distributions are presented to illustrate the dual-functional performance of the encoded metasurface,and the results are consistent with the measured results.We further demonstrate the ability of the anisotropic coding metasurfaces to generate a beam splitter and realize simultaneous anomalous reflections and polarization conversions,thus providing powerful control of differently polarized electromagnetic waves.The proposed method enables versatile beam behaviors under orthogonal polarizations using a single metasurface and has the potential for use in the development of interesting terahertz devices. | Shuo Liu Tie Jun Cui Quan Xu Di Bao Liangliang Du Xiang Wan Wen Xuan Tang Chunmei Ouyang Xiao Yang Zhou Hao Yuan Hui Feng Ma Wei Xiang Jiang Jiaguang Han Weili Zhang Qiang Cheng | 2016 | Light(Science & Applications)2016，5，1： | 36 |
| 4 | Efficacy and safety of a novel anti-HER2 therapeutic antibody RC48 in patients with HER2-overexpressing,locally advanced or metastatic gastric or gastroesophageal junction cancer:a single-arm phase II study显示文摘Background:Current treatment options for human epidermal growth factor receptor 2(HER2)-overexpressing gastric cancer at third-line have shown limited clinical benefit.Further,there is no specific treatment for HER2 immunohistochemistry(IHC)2+and fluorescence in-situ hybridization-negative patients.Here,we report the efficacy and safety of a novel anti-HER2 antibody RC48 for patients with HER2-overexpressing,advanced gastric or gastroesophageal junction cancer.Methods:Patients with HER2-overexpressing(IHC 2+or 3+),locally advanced or metastatic gastric or gastroesophageal junction cancer who were under at least second-line therapy were eligible and received RC482.5 mg/kg alone every 2 weeks.The primary endpoint was the objective response rate(ORR)assessed by an independent review committee.Secondary endpoints included progressionfree survival(PFS),overall survival(OS),duration of response,time to progression,disease control rate,and safety.Results:Of 179 patients screened,125 were eligible and received RC48 treatment.The ORR was 24.8%(95%confidence interval[CI]:17.5%-33.3%).The median PFS and OS were 4.1 months(95%CI:3.7-4.9 months)and 7.9 months(95%CI:6.7-9.9 months),respectively.The most frequently reported adverse events were decreased white blood cell count(53.6%),asthenia(53.6%),hair loss(53.6%),decreased neutrophil count(52.0%),anemia(49.6%),and increased aspartate aminotransferase level(43.2%).Serious adverse events(SAEs)occurred in 45(36.0%)patients,and RC48-related SAEs were mainly decreased neutrophil count(3.2%).Seven patients had adverse events that led to death were not RC48-related.Conclusions:RC48 showed promising activity with manageable safety,suggesting potential application in patients with HER2-overexpressing,advanced gastric or gastroesophageal junction cancer who have previously received at least two lines of chemotherapy. | Zhi Peng Tianshu Liu Jia Wei Airong Wang Yifu He Liuzhong Yang Xizhi Zhang Nanfeng Fan Suxia Luo Zhen Li Kangsheng Gu Jianwei Lu Jianming Xu Qingxia Fan Ruihua Xu Liangming Zhang Enxiao Li Yuping Sun Guohua Yu Chunmei Bai Yong Liu Jiangzheng Zeng Jieer Ying Xinjun Liang Nong Xu Chao Gao Yongqian Shu Dong Ma Guanghai Dai Shengmian Li Ting Deng Yuehong Cui Jianmin Fang Yi Ba Lin Shen | 2021 | Cancer Communications2021，41，11： | 29 |
| 5 | Identifying paleoflood deposits archived in Zhongba Site,the Three Gorges reservoir region of the YangtzeRiver,China显示文摘Based on the principle that the present is the key to the past , detailed analyses, such as AMS 14C dating, grain size, component and morphology of heavy minerals, micro-morphology of zircon, Rb/Sr, magnetic susceptibility and total organic carbon (TOC), were conducted to identify paleoflood sediments archived in Zhongba Site. The results indicate that the plaeoflood sediments bear great similarities with modern flood sediments in the following aspects: (1) probability cumulative curves mainly show a pattern of 3―4 segments; (2) grain-size distribution of suspended matter ranges between 3 and 10Ф; (3) the sediments are well-sorted, most of which are suspended matter (>50%); (4) the same species, quantity and morphology of heavy minerals; (5) scanning electronic microscope images show that shapes of zircon are mainly oval and nearly spheral, rounded due to long-distance transport; (6) higher Rb/Sr values (0.55―0.66)than those of sediments from cultural layers (0.03―0.26); (7) magnetic susceptibility values (133.73―433.05 10-6m3/kg) are lower than those of sediments from cultural layers (959.25―2442.44 10?6 m3/kg); (8) TOC (0.14%―0.33%) are lower than those of sediments from cultural lay-ers (1.13%―2.95%). Our results demonstrate that, except for the 1981 flood, there are at least six paleoflood events that occurred during the Qing Dynasty, the middle of Song Dy-nasty, the early Warring States (400BC―350BC), the West Zhou Dynasty (920BC―900BC), the Xia Dynasty (2070BC―1600BC), and the late Neolithic Age (3000BC―2300BC), respectively . | ZHU Chen ZHENG Chaogui MA Chunmei SUN Zhibin ZHU Guangyao WANG Huilin GAO Huazhong WANG Pengling HUANG Run | 2005 | Chinese Science Bulletin2005，50，21： | 28 |
| 6 | Using iron fertilizer to control Cd accumulation in rice plants: A new promising technology显示文摘Effects of two kinds of iron fertilizer, FeSO4 and EDTA·Na2Fe were studied on cadmium accumulation in rice plants with two rice genotypes, Zhongzao 22 and Zhongjiazao 02, with soil culture systems. The results showed that application of iron fertilizers could hardly make adverse effects on plant growth and rice grain yield. Soil application of EDTA·Na2Fe significantly reduced the Cd accumulation in rice roots, shoots and rice grain. Cd concentration in white rice of both rice genotypes in the treatment of soil application of EDTA·Na2Fe was much lower than 0.2 mg/kg, the maximal Cd permission concentra- tion in cereal crop foods in State standard. However, soil application of FeSO4 or foliar application of FeSO4 or EDTA·Na2Fe resulted in the significant increase of Cd accumulation in rice plants including rice grain compared with the control. The results also showed iron fertilizers increased the concentra- tion of iron, copper and manganese element in rice grain and also affected zinc concentration in plants. It may be a new promising way to regulate Cd accumulation in rice grain in rice production through soil application of EDTA·Na2Fe fertilizers to maintain higher content of available iron and ferrous iron in soils. | SHAO GuoSheng, CHEN MingXue, WANG DanYing, XU ChunMei, MOU RenXiang, CAO ZhaoYun & ZHANG XiuFu China National Rice Research Institute, Hangzhou 31006, China | 2008 | Science China(Life Sciences)2008，51，3： | 28 |
| 7 | Influence of temperature and solution composition on the formation of calcium sulfates显示文摘Calcium sulfates (anhydrite and hydrates) were synthesized by mixing CaCl 2 and Na 2 SO 4 solutions at room temperature followed by aging the resulting slurries at elevated temperatures. The variation of the morphology and structure of the calcium sulfates with aging temperature was investigated. Experimental results indicated that CaSO 4 ·2H 2 O plates, CaSO 4 ·0.5H 2 O whiskers and CaSO 4 spindles were formed at ≤100 °C, 130–160 °C and ≥170 °C, respectively. The formation and conversion of the calcium sulfates were discussed on the basis of characterization of the products and chemical analysis of the solutions. Compared to NaCl solution, pure water favors one-dimensional hydrothermal growth of CaSO 4 ·0.5H 2 O whiskers owing to lower supersaturation. | Kangbi Luo Chunmei Li Lan Xiang Huping Li Ping Ning | 2010 | Particuology2010，8，3： | 26 |
| 8 | Molecular Mechanisms of Leaf Morphogenesis显示文摘工厂维持能力作为茎的主要侧面的附器在整个他们的生命周期和形式叶子形成侧面的附器。叶子在射击的外部地区开始顶端的分裂组织然后发展成弄平的结构。在大多数植物,叶作为一块太阳的面板工作,在光合作用把二氧化碳和水变换成糖类和氧的地方。为了生产结构,那能最佳地完成这功能,植物精确控制叶子的开始,形状,和极性。而且,叶开发是高度灵活的 ? 但是与保存规章的机制跟随普通主题。叶子可能从被变换成确定的、弄平的结构的侧面的分支演变。许多另外的植物部分例如花的器官,被认为专业化叶子,并且因此,叶开发位于他们的形态发生下面。这里,我们在三维的叶形式怎么被建立的理解考察最近的进展。我们集中基因,植物激素,和机械性质怎么调制叶开发,并且讨论 ? 在叶开始,极性建立和维护,变平的叶,和闰的生长的上下文的这些因素。 | Fei Du Chunmei Guan Yuling Jiao | 2018 | Molecular Plant2018，11，9： | 25 |
| 9 | Climate changes in East China since the Late-glacial inferred from high-resolution mountain peat humification records显示文摘High-resolution peat humification records were obtained from Dajiuhu of the Shennongjia Mountains and Qianmutian of the Tianmu Mountains to study climate changes in East China.The analyses of pollen,organic matters,TOC,and Rb/Sr indicate a high degree of peat humification and thus strong decomposition of organic matter when climate was dry.Conversely,when climate was humid,the degree of humification is low because peat was preserved in a waterlogged condition.Peat humification from Dajiuhu occurred not only during the Younger Dryas(about 11.4-12.6 cal ka BP),the Blling-Allerd Warm Period(12.6-15.2 cal ka BP),and the Oldest Dryas(about 15.2-16.0 cal ka BP),but also during the early Holocene(about 11.4-9.4 cal ka BP),the 8.2 cal ka BP cold event,and the Holocene Optimum(about 7.0-4.2 cal ka BP).Both peat humification records since nearly 5 ka BP are consistent,showing that mountain peatland has synchronous responses to the East Asia monsoon-induced precipitation.The LOI data confirm the above observation.The monsoon precipitation since nearly 5 ka BP recorded in these two peat profiles can be divided into three phases.During 4.9-3.5 ka BP,precipitation amount was high but fluctuated greatly.During 3.5-0.9 ka BP,precipitation amount was low.During 0.9-0 ka BP,degree of humification reduced gradually,indicating the increase of monsoon precipitation.Contrast to other high-resolution records from East China monsoon region shows that the monsoon precipitation records of the two peat profiles since nearly 16 ka BP are controlled by a common forcing mechanism of summer solar radicalization in the Northern Hemisphere. | MA ChunMei ZHU Cheng ZHENG ChaoGui YIN Qian ZHAO ZhiPing | 2009 | Science China Earth Sciences2009，52，1： | 22 |
| 10 | Kinetics and equilibrium of adsorption of dissolved organic matter fractions from secondary effluent by fly ash显示文摘Fly ash was used as a low-cost adsorbent for removing dissolved organic matter (DOM) in secondary effluent. Batch experiments were conducted under various adsorbent dosages, pH, contact time, temperatures and DOM fractional characteristics. Under the optimum conditions of fly ash dosage of 15 g/L, temperature of 303 K and contact time of 180 min, a removal of 22.5% of the dissolved organic carbon (DOC), 23.7% of UV-254, 25.9% of the trihalomethanes precursors in secondary effluent was obtained. The adsorption of DOM fractions onto fly ash all followed the pseudo second-order kinetic model, and the hydrophilic fraction adsorption by fly ash also fitted the intraparticle diffusion model quite well. Freundlich and Langmuir models were applicable to the fly ash adsorption and their constants were evaluated. The maximum adsorption capacities of the adsorptions revealed that fly ash was more effective in adsorbing hydrophilic fraction than the acidic fractions. Structure changes of the DOM fractions after fly ash adsorption were also characterized via spectrum analyzing. Those mechanisms presented critical step toward improved efficiencies of fly ash adsorption via further surface-modification. | Liangliang Wei Kun Wang Qingliang Zhao Chunmei Xie Wei Qiu Ting Jia | 2011 | Journal of Environmental Sciences2011，23，7： | 21 |
| 11 | Viral effector protein manipulates host hormone signaling to attract insect vectors显示文摘 | Dewei Wu Tiancong Qi Wan-Xiang Li Haixia Tian Hua Gao Jiaojiao Wang Jin Ge Ruifeng Yao Chunmei Ren Xian-Bing Wang Yule Liu Le Kang Shou-Wei Ding Daoxin Xie | 2017 | Cell Research2017，27，3： | 20 |
| 12 | High-resolution geochemistry records of climate changes since late-glacial from Dajiuhu peat in Shennongjia Mountains,Central China显示文摘A peat core with depths of 297 cm was obtained from the Dajiuhu Basin(31°29′27″N,109°59′45″E,1760 m)in Hubei Province,Central China.10 AMS ages provide a time control and reveal that this core spans the past about 16.0 kaBP(calibrated age)(1 4C age:13.3 kaBP).Multi-proxy indexes analysis of geochemistry shows the following character of climate and environmental changes since about 16 kaBP:(1) The climate during the late-glacial period was cold and wet as a whole,but fluctuated continually.11.4- 12.6 cal.kaBP,12.6-15.2 cal.kaBP and 15.2-16 kaBP were corresponding respectively to the Younger Drays,Bφlling-Allerφd Warm Period and the Oldest Drays.(2)Inheriting the some climate characteristics of the late-glacial,the climate during the early-Holocene was wet and temperature increased gradually,during which an obvious dry event around 10.6 cal.kaB appeared.(3)The climate during the mid-Holocene was genarally warm and wet.During 9.2-7.5 kaBP,temperature increased gradually, precipitation was less comparatively and the 8.2 kaBP cold event which might be representative in the globe was reflected markedly.Then,multi-proxy records were relatively stable during 6.7-4.2 kaBP, which shows the best water and thermal condition in the Holocene Optimum.(4)Around 4.2 kaBP,the climate and environment transform from warm and wet to cool and dry,which may result in the collapse of the Neolithic Culture and midwifery the civilization of Xia Dynasty in this region.After 0.9 kaBP,the climate turned cool and wet.Climate and environmental changes archived in Dajiuhu peat respond to the global changes since the late-glacial period and can be contrasted to the changes recorded in other high-resolution archives from the East Asia Monsoon region,which take on the variety model that the monsoon strengthened abruptly after the late-glacial,was strong during the early Holocene,subse- quently declined and became weak after the middle Holocene with dry climate.According to our analysis,the driving mechanism should be the response of solar radiation changes in the East Asia Monsoon region at middle latitudes. | MA ChunMei ZHU Cheng ZHENG ChaoGui WU ChunLin GUAN Yong ZHAO ZhiPing HUANG LinYan HUANG Run | 2008 | Chinese Science Bulletin2008，53，S1： | 19 |
| 13 | Pigment signatures of some diatoms isolated from China seas显示文摘The photosynthetic pigments of 12 species (14 strains) of cultured diatoms from six genera under specific conditions were examined by the HPLC. The diatom genera were Skeletonema, Thalassiosira, Chaetoceros, Nitzschia, Phaeodactylum and Meuniera. All strains were isolated from China seas and most of them were from the Jiaozhou Bay, China. Fifteen pigments were identified and eight of them were various chlorophyll a derivatives. Chlorophyll a, c2 and c1 and the carotenoids fucoxanthin, diadinoxanthin, diatoxanthin and β, β-carotene existed in all species. The ratios of each pigment to chlorophyll a were compared with the results in literatures. The pigment ratios of this study generally fall within the ranges reported by the literatures although the maximum ratio of fucoxanthin to chlorophyll a was higher and the ratios of chlorophyll c and diatoxanthin to chlorophyll a were low. The pigment ratios are useful to understanding the pigment signatures of diatoms in the Jiaozhou Bay, China, and to setting up the chemotaxonomic method of phytoplankton in these sea areas. | YAO Peng YU Zhigang DENG Chunmei | 2006 | Acta Oceanologica Sinica2006，25，1： | 18 |
| 14 | Emission factors of gaseous carbonaceous species from residential combustion of coal and crop residue briquettes显示文摘Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO2, CO, CH4, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4- dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO2. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants. | Qin WANG Chunmei GENG Sihua LU Wentai CHEN Min SHAO | 2013 | Frontiers of Environmental Science & Engineering2013，7，1： | 17 |
| 15 | Characteristics of paleoflood deposits archived in unit T0403 of Yuxi Site in the Three Gorges reservoir areas,China显示文摘Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research the paleoflood sediments archived in the Yuxi Site.The research indicates that, since 7.6 kaBP,at least 16 times of paleoflood with water level above Wusong Elevation 147.024 m(a.s.l.) left deposits in the Neolithic layers of unit T0403 from the Yuxi Site.The results are induced from the following aspects:(1)The plaeoflood sediments take on great similarities with modern flood sediments in the Yuxi Site and Zhongba Site in probability cumulative curves which mainly show a pattern of 3 segments in fluvial pattern.(2)There is some resemblance between the heavy mineral components and the zircon shape characteristics of paleoflood deposits and those of modern flood deposits.(3) Magnetic susceptibility values(40.44―70.10SI)are lower than those of sediments from cultural layers (59.59―188.68SI).(4)Hg values(290.71―742.51 ng/g)are lower than those of sediments from cultural layers(344.16―10518.17 ng/g).(5)Rb/Sr values are higher than those of sediments from cultural layers, while those of the 4th,5th,6th,7th,8th cultural layers are high,which shows that they are inundated by paleoflood.The reason for many flood deposits existing is related to the site situated on the first terrace where the Yuxi River joins with the Yangtze River.As there are some similarities between the plaeoflood sediments and those of the Zhongba Site,it is feasible to confirm the existence of paleoflood sediments based on the above points. | ZHU Cheng MA ChunMei XU WeiFeng BAI JiuJiang ZHENG ChaoGui ZHU GuangYao WANG HuiLin CHEN Ye LU XueFeng | 2008 | Chinese Science Bulletin2008，53，S1： | 16 |
| 16 | Spore-pollen-climate factor transfer function and paleoenvironment reconstruction in Dajiuhu,Shennongjia,Central China显示文摘The identified results of 121 surface sediment spore-pollen samples in Shennongjia and meteorological data base of 30 years(January,1971―December,2000)of 7 meteorological stations around Dajiuhu, Shennongjia are used in this study.Selecting 55 species of common spore-pollen with the method of space fitting and stepwise regression we construct the pollen climate factor transfer function of annual mean tem- perature:T=7.649-2.33097X Abies -0.10873X Betula -0.17352X Compositae -0.13176X Cruciferae +0.13356XEuphorbiaceae -0.83069X Campanulaceae +1.96494XPyrrosia+0.38411XPteris+2.77741XSelaginella+0.04439XMonolites.We had reconstructed annual mean temperature series by use of the sporo-pollen samples concentra-tion percentage in peat section with 297 cm thickness in Dajiuhu since 15.753 kaBP.The temperature series reflect well the character of climatic change since the late glacial,which indicates extreme cold climate event of the Oldest Dryas,the Older Dryas,the Younger Dryas and the 8.2 kaBP,the same to the climate fluctuations of Bolling Warm Period and Allerod Warm Period,and the character of temperature change fluctuating frequently at the transition age from the late glacial to the Holocene.The reconstructed temperature also indicate Holocene Optimum,late Holocene warm-dry climate,and the character of climatic change in Dajiuhu in the last 1 ka.The conclusion is that the sporo-pollen samples have important climatic significance to surface sediment and the section of Dajiuhu,Shennongjia and important reference value to studying climatic change during the last glaciation by the temperature transfer function and reconstructed temperature series. | ZHU Cheng CHEN Xing ZHANG GuangSheng MA ChunMei ZHU Qing LI ZhongXuan XU WeiFeng | 2008 | Chinese Science Bulletin2008，53，S1： | 15 |
| 17 | Effects of soil water and nitrogen availability on photosynthesis and water use efficiency of Robinia pseudoacacia seedlings显示文摘The efficient use of water and nitrogen (N) to promote growth and increase yield of fruit trees and crops is well studied.However,little is known about their effects on woody plants growing in arid and semiarid areas with limited water and N availability.To examine the effects of water and N supply on early growth and water use efficiency (WUE) of trees on dry soils,one-year-old seedlings of Robinia pseudoacacia were exposed to three soil water contents (non-limiting,medium drought,and severe drought) as well as to low and high N levels,for four months.Photosynthetic parameters,leaf instantaneous WUE (WUEi) and whole tree WUE (WUEb) were determined.Results showed that,independent of N levels,increasing soil water content enhanced the tree transpiration rate (Tr),stomatal conductance (Gs),intercellular CO2 concentration (Ci),maximum net assimilation rate (Amax),apparent quantum yield (AQY),the range of photosynthetically active radiation (PAR) due to both reduced light compensation point and enhanced light saturation point,and dark respiration rate (Rd),resulting in a higher net photosynthetic rate (Pn) and a significantly increased whole tree biomass.Consequently,WUEi and WUEb were reduced at low N,whereas WUE i was enhanced at high N levels.Irrespective of soil water availability,N supply enhanced Pn in association with an increase of Gs and Ci and a decrease of the stomatal limitation value (Ls),while Tr remained unchanged.Biomass and WUEi increased under non-limiting water conditions and medium drought,as well as WUEb under all water conditions;but under severe drought,WUEi and biomass were not affected by N application.In conclusion,increasing soil water availability improves photosynthetic capacity and biomass accumulation under low and high N levels,but its effects on WUE vary with soil N levels.N supply increased Pn and WUE,but under severe drought,N supply did not enhance WUEi and biomass. | Xiping Liu Yangyang Fan Junxia Long Ruifeng Wei Roger Kjelgren Chunmei Gong Jun Zhao | 2013 | Journal of Environmental Sciences2013，25，3： | 15 |
| 18 | Climate and environment reconstruction during the Medieval Warm Period in Lop Nur of Xinjiang, China显示文摘We made multi-proxy analysis of 14C, grain size, microfossils, plant seeds, and geochemical elements on samples from a profile in the central West Lake of Lop Nur. The grain size suggests relatively stable sedimentary environment around the Medieval Warm Period (MWP) with weak storm effect, which is followed by frequent strong storm events. Abundant microfossils and plant seeds in this stage indicate a warm and humid fresh to brackish lake environment. C, N, and stable elements are high in content in the sediments while Rb/Sr, Ba/Sr, and Ti/Sr are in a steady low level. In addition, plenty of red willows lived here prior to about 700 a B.P., indicating a favorable environmental condition. The results indicate that the environment in Lop Nur and its west bank turned to be favorable at about 2200 a B.P., where the Loulan Culture began to thrive. Then the climate and environment came to be in the good condition in the Tang and Song Dynasties, when the storm effect became weaker, rainfall increased and the salty lake water turned to be brackish to fresh lake water. Hence, limnic biomass increased with higher species diversity. | MA ChunMei WANG FuBao CAO QiongYing XIA XunCheng LI ShengFeng Li XuSheng | 2008 | Chinese Science Bulletin2008，53，19： | 13 |
| 19 | Effect of various crop rotations on rice yield and nitrogen use efficiency in paddy–upland systems in southeastern China显示文摘To evaluate the effects of various rotation systems on rice grain yield and N use efficiency, a paddy–upland cropping experiment(2013–2016) was conducted in southeastern China. The experiment was designed using six different rice––winter crop rotations: rice–fallow(RF),rice–wheat(RW), rice–potato with rice straw mulch(RP), rice–green manure(Chinese milk vetch; RC–G), rice–oilseed rape(RO), and rice–green manure crop(oilseed rape with fresh straw incorporated into soil at flowering; RO–G) and three N rates, N0(0 kg N ha-1), N1(142.5 kg N ha-1), and N2(202.5 kg N ha-1). Average rice yields in the RF(5.93 t ha-1) rotation were significantly lower than those in the rotations with winter crops(7.20–7.48 t ha-1)under the N0 treatment, suggesting that incorporation of straw might be more effective for increasing soil N than winter fallow. The rice yield differences among the rotations varied by year with the N input. In general, the grain yields in the RP and RO–G rotations –were respectively 11.6–28.5% and 14.80–37.19% higher than those in the RF in plots with N applied. Increasing the N rate may have tended to minimize the average yield gap between the RF and the other rotations; the yield gaps were 18.55%, 4.14%, and 0.23% in N0, N1, and N2, respectively. However, the N recovery efficiency in the RF was significantly lower than that in other rotations, except for 2015 under both N1 and N2 rates, a finding that implies a large amount of chemical N loss. No significant differences in nitrogen agronomic efficiency(NAE) and physiological efficiency(NPE) were found between the rotations with legume(RC–G) and non–legume(RO and RW) winter crops, a result that may be due partly to straw incorporation. For this reason, we concluded that the return of straw could reduce differences in N use efficiency between rotations with and without legume crops. The degree of synchrony between the crop N demand and the N supply was evaluated by comparison of nitrogen balance degree(NBD) values. The NBD values in the RP and RW were significantly lower than those in the other rotations under both N1 and N2 rates. Thus,in view of the higher grain yield in the RP compared to the RW under the N1 rate, the RP rotation might be a promising practice with comparable grain yield and greater N use efficiency under reduced N input relative to the other rotations. The primary yield components of the RF and RP were identified as number of panicles m-2 and numbers of kernels panicle-1, respectively. The NAE and NPE were positively correlated with harvest index, possibly providing a useful indicator for evaluating N use efficiency. | Song Chen Shaowen Liu Xi Zheng Min Yin Guang Chu Chunmei Xu Jinxiang Yan Liping Chen Danying Wang Xiufu Zhang | 2018 | The Crop Journal2018，6，6： | 13 |
| 20 | Signal overcomplete representation and sparse decomposition based on redundant dictionaries显示文摘Decomposing a signal based upon redundan dictionaries is a new method for data representation on sig- nal processing. It approximates a signal with an overcom- plete system instead of an orthonormal basis to provide a sufficient choice for adaptive sparse decompositions. Re- placing the original data with a sparse approximation can result in not only a higher compression ratio, but also greater flexibility in capturing the inherent structure of the natura signals with the redundancy of dictionaries. This paper gives an overview of a series of recent results in this field, and deals with the relationship between sparsity of signal de- composition and incoherence of dictionaries with BP and MP algorithms. The current and future challenges of the dic- tionary construction are discussed. | ZHANG Chunmei YIN Zhongke CHEN Xiangdong XIAO Mingxia | 2005 | Chinese Science Bulletin2005，50，23： | 13 |
您所在的机构暂未开通此部分的功能，请联系管理员