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The mid-domain effect in flowering phenology

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Plant Diversity 2024年第4期46卷 502-509页

作者： Yanjun Du rongchen Zhang Xinran Tang Xinyang Wang Lingfeng Mao Guoke Chen Jiangshan Lai Keping Ma School of Tropical Agriculture and Forestry(School of Agricultural and Rural Affairs School of Rural Revitalization)Hainan UniversityHaikou 570228China HNU-ASU Joint International Tourism College Hainan UniversityHaikou 570228China School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200062China College of Ecology and Environment Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

The timing of flowering is an important driver of species distribution and community assembly ***,we still have much to learn about the factors that shape flowering diversity(i.e.,number of species flowering per period) in plant *** potential explanation of flowering diversity is the mid-domain effect,which states that geometric constraints on species ranges within a bounded domain(space or time) will yield a mid-domain peak in diversity regardless of ecological ***,we determine whether the mid-domain effect explains peak flowering time(i.e.,when most species of communities are flowering) across *** used phenological data of 16,267 herbaceous and woody species from the provincial Flora in China and species distribution data from the Chinese Vascular Plant Distribution Database to determine relationships between the observed number of species flowering and the number of species flowering as predicted by the mid-domain effect model,as well as between three climatic variables(mean minimum monthly temperature,mean monthly precipitation,and mean monthly sunshine duration).We found that the mid-domain effect explained a significant proportion of the temporal variation in flowering diversity across all species in ***,the mid-domain effect explained a greater proportion of variance in flowering diversity at higher latitudes than at lower *** patterns of flowering diversity for both herbaceous and woody species were related to both the mid-domain effect and environmental *** findings indicate that including geometric constraints in conjunction with abiotic and biotic predictors will improve predictions of flowering diversity patterns.

关键词： Flowering diversity Functional biogeography Latitudinal gradient Macroecology Macrophenology Null model

Chemical composition， biological activities and product development of Gastrodia elata: a review

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Food Science and Human Wellness 2024年

作者： yuchen Jiang Liankui Wen Wenqi Wang rongchen Zhu Jiahua Liu Yang He Fei Zheng yuzhu Wu Department of Food Science and Engineering， Jilin Agricultural University Jilin Ginseng Academy， Changchun University of Chinese Medicine National Engineering Research Center for Wheat and Corn Deep Processing

Gastrodia elata Blume (G. elata) has a rich history of traditional Asian use. However， there is still a need for systematic analysis regarding the relationship and in-depth development between its components and functions. Through comprehensive analysis utilizing databases such as PubMed， Web of Science， and Google Scholar， the practical components， biological activities， and product development of G. elata have been investigated. It has been found that the main active components of G. elata， such as Gastrodin and Gastrodia Polysaccharides， possess functionalities in improving conditions such as epilepsy， hypertension， and osteoporosis. These active components exhibit phenolic hydroxyl groups， molecular weight， conformation， and spatial arrangement， contributing to their enhanced ability to scavenge free radicals. Additionally， G. elata is known to have organic acids and esters， which exhibit potential immune regulatory and antiviral properties. Compounds with multiple acidic functional groups exhibit even more vigorous activity. Steroidal compounds like β-sitosterol， due to their presence of alcohol and ketone groups， along with a multi-ring structure， exhibit superior cholesterol-lowering activity. G. elata has already been recognized in the Traditional Chinese Medicine and Food Homology list， showcasing its potential for development in line with the health demands of the current era. However， challenges regarding quality evaluation， peculiar odor， and the extraction process of the practical components still require immediate attention. Constructing a robust evaluation system and optimizing product processing techniques will be crucial for the future advancement of the G. elata industry.

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Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： WANG yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

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基于相位统计信息特征的相移键控类信号识别

哈尔滨工程大学学报 2024年第6期45卷 1202-1209页

作者：张晓林李铭孙溶辰哈尔滨工程大学信息与通信工程学院黑龙江哈尔滨150001

为解决非协作通信中,相移键控类信号由于相位相似,导致在复杂环境下的分类识别困难的问题,本文在高斯噪声下通过对信号相位信息概率密度的推导,并使用高斯核密度估计的方法得到了一种恢复信号相位信息特征的方法。通过仿真实验将该方法... 详细信息

为解决非协作通信中,相移键控类信号由于相位相似,导致在复杂环境下的分类识别困难的问题,本文在高斯噪声下通过对信号相位信息概率密度的推导,并使用高斯核密度估计的方法得到了一种恢复信号相位信息特征的方法。通过仿真实验将该方法从加性高斯噪声推广到加性Alpha稳态分布噪声中。在该方法下,本文提出的特征对BPSK、QPSK、OQPSK、π/4_DQPSK、8 PSK 5类信号在Alpha噪声下可以准确识别。研究表明:使用支持向量机方法可以在信噪比0 dB以上时使信号的总体识别率达到90%以上。

关键词：非协作通信高斯核密度估计相位信息特征 Alpha稳态分布噪声相移键控调制识别信噪比支持向量机方法

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Approximate analytical solutions for threedimensional ascent trajectory of a solid-fuel launch vehicle with time-varying mass flow rate

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Chinese Journal of Aeronautics 2024年第10期37卷 275-293页

作者： Qi yu Wanchun CHEN Wenbin yu School of Astronautics Beihang UniversityBeijing 102206China

In the scenario that a solid-fuel launch vehicle maneuvers in outer space at high angles of attack and sideslip for energy management,Approximate Analytical Solutions(AAS)for the threedimensional(3D)ascent flight states are derived,which are the only solutions capable of considering time-varying Mass Flow Rate(MFR)at *** uneven MFR makes the thrust vary nonlinearly and thus increases the difficulty of the problem *** AAS are derived based on a 3D Generalized Ascent Dynamics Model(GADM)with a normalized mass as the independent *** simplify some highly nonlinear terms in the GADM,several approximate functions are introduced carefully,while the errors of the approximations relative to the original terms are regarded as minor ***,a finite series with positive and negative exponents,called Exponent-Symmetry Series(ESS),is proposed for function approximation to decrease the highest exponent in the AAS so as to reduce computer round-off *** calculate the ESS coefficients,a method of seeking the Optimal Interpolation Points(OIP)is proposed using the leastsquares-approximation *** to the artful design of the approximations,the GADM can be decomposed into two analytically solvable subsystems by a perturbation method,and thus the AAS are obtained ***,to help implement the AAS,two indirect methods for measuring the remaining mass and predicting the burnout time in flight are put forward using information from *** results verify the superiority of the AAS under the condition of time-varying MFR.

关键词： Approximate analytical solutions 3D ascent trajectory Solid-fuel launch vehicle Uneven thrust Energy management

Low-melting mixture solvents: extension of deep eutectic solvents and ionic liquids for broadening green solvents and green chemistry

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Green Chemical Engineering 2024年第4期5卷 409-417页

作者： yu Chen Zhiwu yu MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology Department of ChemistryTsinghua University

Green solvents such as water and ionic liquids(ILs) are pillars of the great mansion of green chemistry and green processing. Initially proposed as a new family of ILs,deep eutectic solvents(DESs) have received fast development in the past two decades. In this contribution,DESs are reviewed critically and the concept is extended to lowmelting mixture solvents(Lo MMSs),which cover all kinds of materials including ionic compounds,molecular compounds,and metals. Six classes of Lo MMSs are proposed as the new classification system and examples are given. Finally,several thermodynamic issues concerning Lo MMSs are discussed. Two new concepts,robustness of Lo MMSs and high-entropy Lo MMSs,are proposed.

关键词： Green solvents Deep eutectic solvents Low transition temperature mixture solvents Phase diagram EGaIn

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： yu ZHANG yu Jun ZHU School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy

A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-Qi yu Tao yu Jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

Exclusive enteral nutrition for treating pediatric Crohn’s disease

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World Journal of Pediatrics 2024年第9期20卷 869-871页

作者： yu yu Jie Chen Department of Gastroenterology Children’s HospitalNational Clinical Research Center for Child HealthZhejiang University School of MedicineHangzhou 310052China

Crohn's disease(CD),an enduring and relapsing condition afecting the gastrointestinal tract,manifests in a spectrum of symptoms and clinical manifestations that can profoundly afect quality of life[1].Recently,CD has emerged as a global burden of *** China,the prevalence and incidence of childhood infammatory bowel disease(IBD)have steadily increased,from 0.5 per 1 million in 2001 to 6.0 per 1 million in 2010[2].Pediatric patients often face a longer treatment duration than adults.

关键词： Crohn pediatric nutrition