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Reproductive system and population genetic structure in a dimorphic cleistogamous species Pseudostellaria heterophylla Pax (Caryophyllaceae)

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Reproductive system and population genetic structure in a di...

Passive imaging through dense scattering media

生态文明建设中的植物学：现在与未来——中国植物学会第十五届会员代表大会暨八十周年学术年会

作者： LUO Yan bian fu-hua LUO Yi-Bo Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences School of chemistry and biology technology Yantai University

As a multiple strategy of reproduction, dimorphic cleistogamous species produce both closed (cleistogamous, CL) and open (chasmogamous, CH) flowers on the same or different individuals. Pseudostellaria heterophylla Pax consists of populations producing both CH and CL flowers on the same plants, which is found in the temperate forests of eastern China. In this study, floral syndrum and seed production by CH and CL flowers were investigated in populations of P. heterophylla, and the amount and distribution of genetic variation at random amplified polymorphic DNA (RAPD) levels were investigated. The CH flowers were produced in apical plant, and CL flowers were only observed in axial, which are completely covered by the leaf. The CH flower was signifcantly larger, and its pollen/ovule ratio was approximately 142 times higher than that of CL flowers. The number of produced mature flowers and the average seed set of CL flowers was seven times higher than CH flowers per plant, indicating predominant self-fertilization via cleistogamy and self-pollination prior to anthesis in CH flowers. However, the CH seeds were significantly heavier than the CL seeds, and the emergence of CH seedlings were significantly higher than that of CL seedlings. In addition to outcrossing, CH flowers were capable of delayed selfing. Both CH and CL flowers contributed to reproduction in P. heterophylla as well as delayed CH selfing, thereby creating a mating system that may be an adaptation to pollinator or resource unpredictability within the flowering season. The level and pattern of genetic diversity were measured using random amplified polymorphic DNA (RAPD) in 13 wild populations of the species. The average amount of within-population genetic variation was extremely low (Shannon’s information index I= 0.1293). At the species level, the estimates of total gene diversity (H T ) were 0.124. A high level of genetic differentiation occurred between populations (G ST = 0. 5784). The pattern of popu

关键词： Pseudostellaria heterophylla dimorphic cleistogamy cleistogamous flower chasmogamous flower RAPD genetic structure.

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Photonics Research 2024年第1期12卷 134-140页

作者： YAOMING bian FEI WANG YUANZHE WANG ZHENFENG fu HAISHAN LIU HAIMING YUAN GUOHAI SITU Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Imaging through non-static and optically thick scattering media such as dense fog,heavy smoke,and turbid water is crucial in various ***,most existing methods rely on either active and coherent light illumination,or image priors,preventing their application in situations where only passive illumination is *** this study we present a universal passive method for imaging through dense scattering media that does not depend on any prior *** the selection of small-angle components out of the incoming information-carrying scattering light and image enhancement algorithm that incorporates timedomain minimum filtering and denoising,we show that the proposed method can dramatically improve the signal-to-interference ratio and contrast of the raw camera image in outfield experiments.

关键词： scattering media illumination

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Effect of Al content in molten steel on interaction between MgO-C refractory and SPHC steel

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Journal of Iron and Steel Research International 2024年第4期31卷 838-848页

作者： fu-bin Gao fu-ming Wang Xiang Zhang Tian-yu Du Xin-hua Wangg School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Handan Iron and Steel Company Hegang GroupHandan 056015HebeiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The effect of Al content in molten steel on the interaction between SPHC steel(0.005-0.068 wt.%Al,and 19×10^(-4)-58×10^(-4)wt.%O)and MgO-C refractory(11.63 wt.%C)was ***-metallic inclusions in the steel were examined at various periods(0,5,15,30,45,and 60 min)as well as the MgO-C interface after 60 min of corrosion at 1600℃.The results show that when MgO-C refractory comes into contact with SPHC steel,the refractory interface consists of three layers arranged from the innermost to the outermost,including the original refractory layer,the dense MgO layer,and the iron infiltration *** carbon in the MgO-C refractories and the Al content in the molten steel undergo a reaction with the MgO in the refractories,resulting in an increase in Mg concentration in the *** Al content in the molten steel from 0.005 to 0.068 wt.%causes a spinel layer to appear at the interface,and the disappearance time of Al_(2)O_(3) inclusions in the steel decreases from 60 to 30 min,while the average MgO content in inclusions ***,controlling the Al content in the molten steel and the smelting duration can help regulate the formation of spinel inclusionsinthe steel.

关键词： MgO-C refractory SPHC steel Inclusion-Spinel Al-killed steel Interfacial reaction

Impact of Local Climate Zones on the Urban Heat and Dry Islands in Beijing:Spatial Heterogeneity and Relative Contributions

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Journal of Meteorological Research 2024年第1期38卷 126-137页

作者： Zuofang ZHENG fu LUO Nana LI hua GAO Yuanjian YANG Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089 School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 Key Laboratory of Urban Meteorology China Meteorological AdministrationBeijing 100089

Based on the building height and density data on a 100-m resolution,hourly 2-m temperature and humidity data at83 automatic weather stations,and gridded local climate zone(LCZ)data on a 120-m resolution in urban Beijing in2020,this study first employs the semivariogram combined with building parameters to calculate spatial correlations and has identified an LCZ grid resolution of 500 m suitable for best usage of the available observation ***,how the spatially heterogeneous LCZs affect and contribute to the canopy urban heat island intensity(UHII)and urban dry island intensity(UDII)are quantitatively *** is found that UHII is high in winter and low in summer with a unimodal diurnal variation while UDI is low in winter but high in summer with a bimodal diurnal *** LCZ with compact mid-rise(open high-rise)buildings exhibits the highest UHII(UDII),followed by the compact high-rise(compact low-rise),while the LCZ of scattered trees presents both the lowest UHII and the lowest *** most significant difference in the UHII(UDII)among the nine LCZ types in the urban area of Beijing is2.62℃(1.1 g kg^(-1)).Area-weighted averaging analysis reveals that the open mid-rise LCZ is the most significant contributor to the UHII(UDII),immediately followed by compact mid-rise(open low-rise),with the least contribution from bare rock or paved(scattered trees).The results also indicate that beyond the intrinsic physical properties of the LCZs of a city,their area proportions cannot be overlooked in evaluating their impact on the UHI and *** quantitatively findings could help urban planners to create a livable urban climate and environment by adjusting the relevant land use.

关键词： local climate zone(LCZ) urban heat island(UHI) urban dry island(UDI) distribution pattern contribution rate Beijing

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PVP/PAN-derived porous carbon fiber for zinc-ion hybrid supercapacitors

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Rare Metals 2024年第7期43卷 3066-3073页

作者： Shu-hua Yang Wen-Qing fu Yan-Wei Cui Bing-Qiang Cao Materials Center for Energy and Photoelectrochemical Conversion School of Material Science and EngineeringUniversity of JinanJinan 250022China

Porous carbon fibers are promising cathodes for zinc-ion hybrid supercapacitors(ZHSs)owing to their abundant active sites,great conductivity,and stable physical and chemical ***,designing a proper preparation technique to regulate the microstructure of carbon fibers still remains a great ***,a poly vinylpyrrolidone/po-lyacry lonitrile(PVP/PAN)-derived porous carbon fiber is developed via the PVP/PAN blend electrospinning and hydrothermal selective PVP removal *** hydrothermal selective PVP removal strategy can effectively avoid a cross-linking between PVP and PAN during the traditional stabilization at air *** PVP/PAN-derived porous carbon fiber,the sufficient micropores provide abundant space for the Zn^(2+)storage,whereas the proper mesopores contribute to the fast ion *** hierarchical porous structures endow ZHSs with high specific capacity and high-rate *** ZHS assembled with the optimal PVP/PAN-derived porous carbon fiber(PVP-PANC-0.8)displays an outstanding specific capacity of 208 mAh·g^(-1),high rate capability(49.5%)from 0.5 to 5 A·g^(-1),and 72.25%capacity retention after 10,000 cycles at 0.5 A·g^(-1).

关键词： Zinc-ion hybrid supercapacitors Porous carbon fibers Hierarchical porous structures Electrospinning

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Effect of Platelet-rich Plasma in Stimulating Macrophage Transformation into M2 Type under AMPK Signaling Pathway

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Chinese Journal of Biomedical Engineering 2024年第02期33卷 85-92页

作者： ZHONG Chang-rui fu Chun-hua Longyan First Affiliated Hospital of fujian Medical University The Second Hospital of Longyan

Objective: To explore the effect of platelet-rich plasma(RPR) in stimulating the transformation of pro-inflammatory(M1) macrophages into antiinflammatory(M2) under the adenosine-monophosphate-dependent protein kinase(AMPK) signaling pathway. Methods: Rat peritoneal macrophages(RAW264.7) were cultured and randomly divided into 8 groups: blank control group, LPS group, RPR group A, RPR group B, LPS+RPR(12 h) group, LPS+RPR(24 h) group A, LPS+RPR(24 h)group B, LPS+RPR(24 h) group C. RPR was prepared based on blood donors. The expressions of AMPK signaling pathway-related proteins(AMPK, ULK1, m TOR) and macrophage markers(i NOS, Arg-1) in the blank control group, LPS group, LPS+RPR(12 h)group and LPS+RPR(24 h) group were observed and compared. The expressions of macrophage markers in LPS+RPR(24 h) B and C groups were compared, and the expressions of AMPK and TGF-β in RPR A and B groups were compared. Results: The gray values of AMPK and ULK1 in LPS cells decreased significantly, while those in LPS+RPR(12 h) and LPS+RPR(24 h) A cells increased significantly. The gray values of AMPK and ULK1 in LPS+RPR(24 h) A cells were higher than those in LPS+RPR(12 h)cells(P<0.05). The m TOR gray value of LPS cells was significantly higher than that of LPS+RPR(24 h) A cells, and the m TOR gray value of LPS+RPR(24 h) A cells was significantly lower than that of LPS+RPR(12 h) cells(P<0.05). The expression of i NOS in LPS cells was significantly decreased, the expression of i NOS in LPS+RPR(12 h) and LPS+RPR(24 h) cells was significantly increased, and the expression of i NOS in LPS+RPR(24 h) cells was higher than that in LPS+RPR(12 h) cells(P<0.05). The expression of Arg-1 in LPS cells was significantly decreased, the expression of Arg-1 in LPS+RPR(12 h) and LPS+RPR(24 h) A cells was significantly increased, and the expression of Arg-1 in LPS+RPR(24 h) A cells was higher than that in LPS+RPR(12 h)cells(P<0.05). The i NOS expression level of LPS+PRP(24 h) C cells was significantly higher

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Lithium polysulfide solvation and speciation in the aprotic lithium-sulfur batteries

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Particuology 2024年第6期89卷 238-245页

作者： Jinhao Zhang Qingshan fu Peng Li Ruibo Linghu Xiaozhong Fan Haibin Lin Juncao bian Songbai Han Gengzhi Sun Long Kong Frontiers Science Center for Flexible Electronics and Xi’an Institute of Flexible Electronics Northwestern Polytechnical UniversityXi’an710129China China Automotive Innovation Corporation Nanjing211100China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen518055China Institute of Advanced Materials Nanjing Tech UniversityNanjing211816China

Fingerprinting sulfur speciation in aprotic electrolytes is a key to understand fundamental chemistry and design well-performing lithium–sulfur(Li–S)*** polysulfide(LiPS)dissolution and deposition in ether-based electrolytes during redox reactions have been probed and established by spectroscopy and ***,detailed LiPS structure and solvation properties influenced by conventional and newly developed electrolytes remain elusive,which exert fundamental challenges and practical difficulties in decoupling battery performance from electrolyte *** perspective aims to provide timely information to uncover underlying mechanisms that rein in sulfur speciation by considering the charge density of LiPSs and the coordination strength of solvents/*** discussion starts with unlocking the baseline electrolyte formulation to investigate its role in LiPS formation and *** that,the term coordination strength is used instead of donor number and dielectric constant to describe interactions between solvents and LiPSs and to reveal LiPS structure *** work is expected to encourage the discovery of new electrolyte working mechanisms to develop energy-dense and power-intensive Li–S batteries.

关键词： Sulfur speciation Redox kinetics Coordination strength Solvation chemistry Lithium-sulfur batteries

Fabrication and properties of lightweight zirconia with fine closed porosity

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Journal of Iron and Steel Research International 2024年第6期31卷 1449-1458页

作者： Yi-bo Zhang hua-zhi Gu Lv-ping fu Ao huang Mei-je Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Lightweight refractory materials with thermal insulation properties and erosion resistance are advantageous for hightemperature *** zirconia refractories were prepared using starch as a pore-forming agent,basic magnesium carbonate as a stabilizer,and nano-zirconia as an *** effects of the nano-zirconia content on the pore and thermal insulation properties of the lightweight zirconia refractories were investigated based on the porosity,phase composition,microstructure,and thermal ***-zirconia was shown to have a high surface energy,and its addition effectively increased the driving force for sintering,reduced the sintering temperature,and promoted the sintering reaction,thereby reducing the apparent porosity and improving the density of the prepared *** to the superplasticity of nano-zirconia,the surface stress caused plastic deformation between particles,which increased the migration rate of grain boundaries and trapped more gas inside the material before it diffused to the surface,thereby enhancing the closed porosity of the *** presence of closed pores could extend the thermal conduction path,decrease the conduction rate,and hinder the conduction effect to effectively reduce the thermal conductivity of the *** a nano-zirconia content of 0.75 wt.%,the prepared lightweight zirconia had the highest closed porosity and the lowest thermal *** apparent porosity,closed porosity,and total porosity of the material were 2.8%,7.0%,and 9.8%,respectively,and the thermal conductivity at 800℃was 1.37 W m^(-1)k^(-1).

关键词： Sintering Nano-zirconia Closed pore:Thermal conductivity Refractory material

Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2022

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2842-2861页

作者： Qiang-Qiang fu Le Ma Xiao-Min Niu hua-Xin Zhao Xu-hua Ge hua Jin De-hua Yu Sen Yang Department of General Practice Yangpu HospitalSchool of MedicineTongji UniversityShanghai 200090China Shanghai General Practice and Community Health Development Research Center Shanghai 200090China Department of Shanghai Lung Cancer Center Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030China Department of Oncology Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200090China

BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and *** the evolution and current state of research in this field is *** To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic *** This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the"bibliometrix"R package,VOSviewer,and *** analysis focused on the distribution of publications,contributions by institutions and countries,and trends in *** methods included data synthesis,network analysis,and visualization of international collaboration *** This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and *** highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer *** last five years,substantial advancements have been made,representing nearly 45%of the examined *** rates have dramatically increased,from 20 articles in 2002 to 112 in 2022,reflecting intensified research *** study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication *** shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN *** This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research *** calls for enhanced global collaboration and integration of artificial intelligence to improve cancer p

关键词： Gastrointestinal neoplasms Bibliometric analysis Risk assessment Network analysis Research trends