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| 1 | Relative pollen productivities of typical steppe species in northern China and their potential in past vegetation reconstruction显示文摘The Relative Pollen Productivities(RPPs)of common steppe species are estimated using Extended R-value(ERV)model based on pollen analysis and vegetation survey of 30 surface soil samples from typical steppe area of northern China.Artemisia,Chenopodiaceae,Poaceae,Cyperaceae,and Asteraceae are the dominant pollen types in pollen assemblages,reflecting the typical steppe communities well.The five dominant pollen types and six common types(Thalictrum,Iridaceae,Potentilla,Ephedra,Brassicaceae,and Ulmus)have strong wind transport abilities;the estimated Relevant Source Area of Pollen(RSAP)is ca.1000 m when the sediment basin radius is set at 0.5 m.Ulmus,Artemisia,Brassicaceae,Chenopodiaceae,and Thalictrum have relative high RPPs;Poaceae,Cyperaceae,Potentilla,and Ephedra pollen have moderate RPPs;Asteraceae and Iridaceae have low RPPs.The reliability test of RPPs revealed that most of the RPPs are reliable in past vegetation reconstruction.However,the RPPs of Asteraceae and Iridaceae are obviously underestimated,and those of Poaceae,Chenopodiaceae,and Ephedra are either slightly underestimated or slightly overestimated,suggesting that those RPPs should be considered with caution.These RPPs were applied to estimating plant abundances for two fossil pollen spectra(from the Lake Bayanchagan and Lake Haoluku)covering the Holocene in typical steppe area,using the'Regional Estimates of Vegetation Abundance from Large Sites'(REVEALS)model.The RPPs-based vegetation reconstruction revealed that meadow-steppe dominated by Poaceae,Cyperaceae,and Artemisia plants flourished in this area before 6500–5600 cal yr BP,and then was replaced by present typical steppe. | XU QingHai CAO XianYong TIAN Fang ZHANG ShengRui LI YueCong LI ManYue LI Jie LIU YaoLiang LIANG Jian | 2014 | Science China Earth Sciences2014，57，6： | 13 |
| 2 | Surface pollen assemblages of human-disturbed vegetation and their relationship with vegetation and climate in Northeast China显示文摘Pollen assemblages of 53 surface pollen samples from farmlands and wastelands in Northeast China were analyzed. Tree pollen percentages were usually higher than 30%, with Pinus (26.9%), Quercus (0.9%), Betula (0.9%) and Populus (0.7%) as the major types, and herb pollen percentages were usually higher than 50%, with weedy Poaceae (8.7%), Chenopodiaceae (7.1%), Artemisia (1.9%) and Compositae (3.5%) as the major taxa. Thus, the pollen assemblages were consistent with the regional vegetation compositions. However, there were differences in pollen assemblages among regions, especially among different geomorphological units. For example, in the mountains, there were more types of tree pollen and higher total percentages (average 42%) than in other areas, while cereal pollen percentages were lowest (11.2%). In the hills and high plains, herbs made up more than 60% of the pollens, with cereals (average 53.6%) the dominant type. In the low plains, pollen types were similar to those in the hills and high plains, but total pollen concentrations and the proportion of Concentricystes were much higher, while cereal pollen percentages were slightly lower (average 41.6%). Pollen assemblages in different land use types also differed. For example, in farmland, cereal pollen percentages were more than 40% and Chenopodiaceae was usually less than 2.5%, while in wasteland, weedy Poaceae was usually less than 10% and Chenopodiaceae was usually higher than 25%. Total pollen concentrations in farmland (average 3909 grains/g) were much lower than in wasteland (average 15074 grains/g). Redundancy analysis revealed that pollen assemblages were significantly negatively correlated with mean annual temperature (-0.73) and July mean temperature (-0.81) and significantly positively correlated with mean annual precipitation (0.48), indicating that pollen assemblages in the artificial or human-disturbed vegetation reflect regional climate well. Comparison of pollen assemblages in different areas of northern China showed that pollen concentrations reflect the intensities of human impact to some degree. For example, pollen concentrations decrease as human impacts increase in intensity. The cereal pollen proportions in farmland differed by area. In Northeast China, cereal pollen proportions were distinctly higher than in most other areas of northern China, suggesting differences in planting habits and climate. | LI ManYue LI YueCong XU QingHai PANG RuiMing DING Wei ZHANG ShengRui HE ZhiGuo | 2012 | Chinese Science Bulletin2012，57，5： | 10 |
| 3 | Spatial patterns of vegetation and climate in the North China Plain during the Last Glacial Maximum and Holocene climatic optimum显示文摘Reconstructing the spatial patterns of regional climate and vegetation during specific intervals in the past is important for assessing the possible responses of the ecological environment under future global warming scenarios. In this study, we reconstructed the history of regional vegetation and climate based on six radiocarbon-dated pollen records from the North China Plain. Combining the results with existing pollen records, we reconstruct the paleoenvironment of the North China Plain during the Last Glacial Maximum(LGM) and the Holocene Climatic Optimum(HCO). The results show that changes in the regional vegetation since the LGM were primarily determined by climatic conditions, the geomorphic landscape and by human activity.During the LGM, the climate was cold and dry;mixed broadleaf-coniferous forest and deciduous-evergreen broadleaf forest developed in the southern mountains, and cold-resistant coniferous forest and mixed broadleaf-coniferous forest were present in the northern mountains. The forest cover was relatively low, with mesophytic and hygrophilous meadow occupying the southern part of the plain, and temperate grassland and desert steppe were distributed in the north;Chenopodiaceae-dominated halophytes grew on the exposed continental shelf of the Bohai Sea and Yellow Sea. During the HCO, the climate was warm and wet;deciduous broadleaf forest and deciduous-evergreen broadleaf forest, with subtropical species, developed in the southern mountains, and deciduous broadleaf forest with thermophilic species was present in northern mountains. Although the degree of forest cover was greater than during the LGM, the vegetation of the plain area was still dominated by herbs, while halophytes had migrated inland due to sea level rise. In addition, the expansion of human activities, especially the intensification of cultivation,had a significant influence on the natural vegetation. Our results provide data and a scientific basis for paleoclimate modelling and regional carbon cycle assessment in north China, with implications for predicting changes in the ecological environment under future global warming scenarios. | Manyue LI Shengrui ZHANG Qinghai XU Jule XIAO Ruilin WEN | 2019 | Science China Earth Sciences2019，62，8： | 4 |
| 4 | The crystal structure of Ac-AChBP in complex with α-conotoxin LvlA reveals the mechanism of its selectivity towards different nAChR subtypes显示文摘3* nAChRs,被认为为象疼痛那样的问题正在答应药目标,嗜好,心血管的功能,认知混乱等等,在整个中央、外部的神经系统被发现。-conotoxin (-CTx) LvIA 作为迄今为止知道的 32 nAChRs 的最选择的禁止者被识别了,并且它能把 32 nAChR 子类型与 6/323 和 34 种 nAChR 子类型区分开来。然而,它向 32 的选择的机制, 6/323,和 34 nAChRs 留下逃犯。这里,我们在 3.4 的一个决定与 Aplysia californica 醋胆素绑定蛋白质(Ac-AChBP ) 在建筑群报导 LvIA 的合作水晶结构 ? 。基于这建筑群的结构,和基于另外的 nAChR 子类型和有约束力的亲密关系试金当模特儿的相同,我们断定 LvIA 的 Asp-11 在选择起一个重要作用向 32 的 LvIA 和由做盐的 3/623 nAChRs 与老鼠的 Lys-155 衔接 3 子单元。在被老鼠的 Met-36, Thr-59,和 Phe-119 形成的一个恐水病的衣袋以内的 Asn-9 谎言在 32 nAChR 模型的 2 子单元,向 32 nAChR 子类型为它的更多的有势力选择揭示原因。这些结果提供能被用来设计 ligands 的分子的卓见有选择地指向 32 nAChRs,与为新治疗学的 -CTxs 的设计的重要含意。 | Manyu Xu Xiaopeng Zhu Jinfang Yu Jinpeng Yu Sulan Luo Xinquan Wang | 2017 | Protein & Cell2017，8，9： | 3 |
| 5 | The effect of LyPRP/collagen composite hydrogel on osteogenic differentiation of rBMSCs显示文摘Although platelet-rich plasma(PRP)plays a significant role in the orthopedic clinical application,it still faces two major problems,namely,uncontrollable factors release,frequent preparation and extraction processes as well as the inconvenient form of usage.To overcome these shortcomings,freeze-dried PRP(LyPRP)was encapsulated into bioactive Col I hydrogel to induce osteogenic dif-ferentiation of rabbit bone marrow mesenchymal stem cells(rBMSCs).And PRP/Col I composite hydrogel was prepared as a control.Compared with Col I hydrogel,the introduction of platelets significantly improved the mechanical properties of hydrogels.Meanwhile,platelets were evenly distributed in the composite hydrogels network.The sustainable release of related factors in the composite hydrogels could last for more than 14days to maintain its long-term biological activity.Further cell experiments confirmed that PRP and LyPRP could effectively alleviate the contraction of collagen hydrogel in vitro,and promote the adhesion,proliferation and osteogenesis differentia-tion of rBMSCs.The results of osteogenic gene expression indicated that the 10%LyPRP/Col I composite hydrogel could facilitate the early expression of BMP-2 and late osteogenic associated protein formation with higher expression of alkaline phosphatase and Osteocalcin(OCN).These results might provide new insights for the clinical application of 10%LyPRP/Col I composite hydro-gel as practical bone repair injection. | Manyu Chen Quanying Liu Yang Xu Yuxiang Wang Xiaowen Han Zhe Wang Jie Liang Yong Sun Yujiang Fan Xingdong Zhang | 2021 | Regenerative Biomaterials2021，8，1： | 1 |
| 6 | A pH Sensitive Fluorescence Probe Based on Tricarbocyanine显示文摘Medical imaging technologies consist of X-ray imagingtechnology, computed tomography(CT), positron emissioncomputed tomography(PET), ultrasound imaging(USG), mag-netic resonance imaging(MRI) and optical imaging(OI)ill. Theyplay an increasingly important role in diagnosis of disease anddrag research. | YAN Luomei ZHOU Hua WU Cunqi WANG Lidan YANG Wei JIN Manyu ZHAO Yongxia XU Jingwei | 2016 | Chemical Research in Chinese Universities2016，32，6： | 0 |
| 7 | Scalable Core–Sheath Yarn for Boosting Solar Interfacial Desalination Through Engineering Controllable Water Supply显示文摘Tailoring water supply to achieve confined heating has proven to be an effective strategy for boosting solar interfacial evaporation rates.However,because of salt clogging during desalination,a critical point of constriction occurs when controlling the water rate for confined heating.In this study,we demonstrate a facile and scalable weaving technique for fabricating core-sheath photothermal yarns that facilitate controlled water supply for stable and efficient interracial solar desalination.The core-sheath yarn comprises modal fibers as the core and carbon fibers as the sheaths.Because of the core-sheath design,remarkable liquid pumping can be enabled in the carbon fiber bundle of the dispersed superhydrophilic modal fibers.Our woven fabrics absorb a high proportion(92%)of the electromagnetic radiation in the solar spectrum because of the weaving structure and the carbon fiber sheath.Under one-sun(1 kW·m^(-2))illumination,our woven fabric device can achieve the highest evaporation rate(of 2.12kg·m^(-2)·h^(-1) with energy conversion efficiency:93.7%)by regulating the number of core-sheath yarns.Practical application tests demonstrate that our device can maintain high and stable desalination performance in a 5 wt%NaCl solution. | Xingfang Xiao Luqi Pan Tao Chen Manyu Wang Lipei Ren Bei Chen Yingao Wang Qian Zhang Weilin Xu | 2023 | Engineering2023，，11： | 0 |
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