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昆明市东川干热河谷蚂蚁物种多样性

湖北农业科学 2024年第5期63卷 136-142页

作者：诸慧琴徐正会祁彪李彪陈超郭宁妍钱怡顺云南林业职业技术学院昆明650224 西南林业大学生物多样性保护学院云南省森林灾害预警与控制重点实验室昆明650224

为阐明干热河谷蚂蚁多样性规律,采用样地调查法对昆明市东川干热河谷蚂蚁物种多样性进行研究。结果表明,在8个样地中共采集到蚂蚁5亚科24属53种,蚂蚁群落的优势种为罗氏铺道蚁[Tetramorium wroughtonii(Forel)],此外发现常见种7种(占物... 详细信息

为阐明干热河谷蚂蚁多样性规律,采用样地调查法对昆明市东川干热河谷蚂蚁物种多样性进行研究。结果表明,在8个样地中共采集到蚂蚁5亚科24属53种,蚂蚁群落的优势种为罗氏铺道蚁[Tetramorium wroughtonii(Forel)],此外发现常见种7种(占物种总数的13.21%),较常见种11种(占20.75%),较稀有种21种(占39.62%),稀有种13种(占24.53%)。各样地蚂蚁群落主要指标为物种数目5~22种(平均12.8种),个体密度4.8~147.2头/m2(平均62.4头/m2),多样性指数1.0492~2.0480(平均1.4633),均匀度指数0.5058~0.7086(平均0.5954),优势度指数0.2091~0.4866(平均0.3472);蚂蚁群落间相似性系数0.0000~0.3000,显示2个不同样地间相似性处于极不相似至中等不相似水平。东川干热河谷蚂蚁物种丰富度总体偏低,主要是气温和湿度的联合作用对研究区植被类型产生了重要影响,进而影响蚂蚁群落的主要指标。

关键词：蚁科群落生物多样性干热河谷植被恢复

Well-designed g-C_(3)N_(4)nanosheet incorporated Ag loaded Er_(0.05)La_(0.95)FeO_(3)heterojunctions for isoamyl alcohol detection

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Journal of Advanced Ceramics 2024年第6期13卷 736-745页

作者： Kaichun xu Mengjie Han Zichen zheng Zexin Yu Hanlin Liao hui Sun Chao Zhang College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China Institute for Manufacturing Technologies of Ceramic Components and Composites(IMTCCC) University of StuttgartStuttgart 70569Germany ICB UMR 6303 CNRSUniv.Bourgogne Franche-ComtéUTBMBelfort 90010France School of Space Science and Physics Shandong UniversityWeihai 264209China

Because the volatile content of isoamyl alcohol increases sharply on the seventh day of wheat mildew infection,isoamyl alcohol can be used as an early biomarker of wheat mildew ***,only a few sensors for isoamyl alcohol detection have been reported,and these sensors still suffer from low sensitivity and poor moisture ***,the isoamyl alcohol sensitivity of 5 at%Er@LaFeO_(3)(ELFO)was enhanced by loading Ag nanoparticles on the surface of the ELFO microspheres,while the optimal operating temperature was *** moisture resistance of Ag/ELFO was improved by the incorporation of g-C_(3)N_(4)nanosheets(NSs)on the surface of Ag/ELFO through electrostatic *** the requirements for practical applications in grain granaries,the sensing behavior of a Ag/ELFO-based sensor incorporating g-C_(3)N_(4)NSs at 20%relative humidity(RH)was systematically studied,and the sensor demonstrated excellent repeatability,long-term stability,and superior selectivity(791 at 50 ppm)for isoamyl alcohol with a low limit of detection(LOD=75 ppb).Furthermore,the practical results obtained for wheat at different mildew stages further confirmed the potential of the g-C_(3)N_(4)/Ag/ELFO-based sensor for monitoring the early mildew stage of *** work may offer guidance for enhancing the moisture resistance of gas-sensitive materials through the strategy of employing composite nanomaterials.

关键词： Ag gas sensor moisture resistance isoamyl alcohol Er@LaFeO_(3)(ELFO) g-C_(3)N_(4)nanosheet(NS)

Efficient deep blue OLEDs with extremely low efficiency roll-off at high brightness based on phenanthroimidazole derivatives

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Chinese Chemical Letters 2019年第11期30卷 1989-1993页

作者： Xiang Chen Jue-Wen Zhao xu-hui zheng Jie-Ji Zhu Guo-Xi Yang Shan-Shun Tang Qing-Xiao Tong Si-Lu Tao Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province Shantou UniversityGuangdong 515063China School of Optoelectronic Science and Engineering University of Electronic Science and Technology of China(UESTC)Chengdu 610054China

Phosphorescent and thermally activated delayed fluorescence(TADF)emitters can break through the spin statistics rules and achieve great success in external quantum efficiency(over 5%).However,maintaining high efficiency at high brightness is a tremendous challenge for applications of organic light emitting ***,we reported two phenanthroimidazole derivatives PPI-An-CN and PPI-An-TP and achieved extremely low efficiency roll-off with about 99%of the maximum external quantum efficiency(EQEmax)maintained even at a high luminance of 1000 cd/cm2 based non-doped *** doping the two materials in CBP(4,4'-bis(N-carbazolyl)-1,1'-biphenyl),the doped devices still exhibited excellent stability at high brightness with CIEy≈0.07 and low turn-on voltage of only 2.8 *** state-ofthe-art low efficiency roll-off makes the new materials attractive for potential *** is the first time that the Fragment Contribution Analysis method has been used to analyze the excited state properties of the molecules in the field of OLEDs,which helps us understand the mechanism more intuitively and deeply.

关键词： OLED Deep blue Phenanthroimidazole Low efficiency roll-off Fragment contribution analysis

Adsorption,in vitro digestion and human gut microbiota regulation characteristics of three Poria cocos polysaccharides

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Food Science and Human Wellness 2024年第3期13卷 1685-1697页

作者： Fangming Zhang hui zheng Tao zheng Pan xu Yao xu Yuxin Cao Fan Jia Yiqiong Zeng Yubing Fan Kai He Xinwen Dai Fengfei Hou Yong Yang College of Pharmacy Hunan University of Chinese MedicineChangsha 410208China School of Pharmaceutical Science Hunan University of MedicineHuaihua 418000China Hunan Fuling Engineering Technology Research Center Huaihua 418100China

Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep ***,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb ***,the whole PC has also been historically utilized as functional herbal *** the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of *** to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant *** this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three *** polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and *** adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest *** general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful *** gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inh

关键词： Poria cocos polysaccharides Alkali-soluble poria polysaccharide Carboxymethyl poria polysaccharide Adsorption characteristics In vitro simulated digestion In vitro simulated gut microbiota fermentation

Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第3期11卷 159-171页

作者： Rui Wen Shao Jun Wei Wu zheng Xing Wang hui xu Han Qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

Protection of Omicron Sub-Lineage Infection Against Reinfection with Another Omicron Sub-Lineage:Systematic Review,Meta-Analysis,and Meta-Regression-Worldwide,2022-2023

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China CDC weekly 2024年第26期6卷 624-628,I0001-I0009页

作者： xu Guo Zuyao Cheng Junhong Li Yudan Song hui zheng Yamin Wang Chao Ma Zijian Feng National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Disease National Immunization ProgramChinese Center for Disease Control and PreventionBeijingChina Chinese Preventive Medicine Association BeijingChina

Summary What is already known about this topic?Both the decline in immunity over time and the evolution of the virus play a role in the level of protection offered by a prior *** is added by this report?Point estimates indicated variations in protection levels based on the initial infecting variant and the reinfecting *** was a consistent correlation between real-world protection,antigenic distance,and humoral immunity ***,shorter antigenic distances and higher humoral immunity levels corresponded to enhanced real-world *** are the implications for public health practice?Our findings suggest that virological and immunological studies could help identify and assess the epidemic risk posed by new variants before they become *** incorporation of the latest variants into the antigen components of the coronavirus disease 2019(COVID-19)vaccines can significantly contribute to effective epidemic prevention and control measures.

关键词： immunity prevention shorter

A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan Wang Fanjiang xu Quan zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

Challenges and opportunities in Quaternary palynology

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Science China Earth Sciences 2024年第7期67卷 2148-2161页

作者： Qinghai xu Houyuan LU Zhuo zheng College of Geographical Sciences Hebei Key Laboratory of Environmental Change and Ecological ConstructionHebei Normal UniversityShijiazhuang 050024China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519082China

Quaternary palynology plays a pivotal role in investigating global climate change and various other research fields,serving as an essential tool for the quantitative analysis of paleoenvironment ***,due to the vast diversity of terrestrial ecosystems and intricate interactions between vegetation,climate,and human activities,further advancements are required in the following aspects within this discipline.(1)The accuracy of classification in pollen morphology and fossil pollen identification needs improvement,particularly at the species *** represents a significant challenge in present Quaternary ***-aided intelligent recognition holds promise as a solution for species identification based on more detail pollen morphology.(2)Most pollen-based vegetation and climate reconstructions overlook the significance of bare *** bare ground can lead to substantial inaccuracies when quantitatively reconstructing past vegetation and climate.(3)While pollen records provide reliable information on paleoclimate changes,current quantitative climate reconstruction models heavily rely on modern pollen datasets derived from present-day vegetation disturbed more or less by human *** introduces bias and uncertainties into paleoclimate reconstruction.(4)Although pollen can serve as an indicator of human activities,accurately quantifying the intensity of human influence remains *** accurate identification of crop pollen,reconstructing reliable land cover/use data,and integrating multidisciplinary data may enhance the identification and quantification of signals related to human activity in pollen records.

关键词： Quaternary palynology Paleoclimate Paleovegetation Human activity

High-Order Decoupled and Bound Preserving Local Discontinuous Galerkin Methods for a Class of Chemotaxis Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 372-398页

作者： Wei zheng Yan xu School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

In this paper,we explore bound preserving and high-order accurate local discontinuous Galerkin(LDG)schemes to solve a class of chemotaxis models,including the classical Keller-Segel(KS)model and two other density-dependent *** use the convex splitting method,the variant energy quadratization method,and the scalar auxiliary variable method coupled with the LDG method to construct first-order temporal accurate schemes based on the gradient flow structure of the *** semi-implicit schemes are decoupled,energy stable,and can be extended to high accuracy schemes using the semi-implicit spectral deferred correction *** bound preserving DG discretizations are only worked on explicit time integration methods and are difficult to get high-order *** overcome these difficulties,we use the Lagrange multipliers to enforce the implicit or semi-implicit LDG schemes to satisfy the bound constraints at each time *** bound preserving limiter results in the Karush-Kuhn-Tucker condition,which can be solved by an efficient active set semi-smooth Newton *** numerical experiments illustrate the high-order accuracy and the effect of bound preserving.

关键词： Chemotaxis models Local discontinuous Galerkin(LDG)scheme Convex splitting method Variant energy quadratization method Scalar auxiliary variable method Spectral deferred correction method