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Comparative transcriptomes reveal the disjunction adaptive strategy of Thuja species in East Asia and North America

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林业研究:英文版 2023年第6期34卷 1963-1974页

作者： Ermei Chang Xue liu Jiahui Chen Jingyi Sun Shaowei Yang Jianfeng Liu State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 10091People’s Republic of China Chongqing Key Laboratory of Traditional Chinese Medicine Resource Endangered Medicinal Breeding National Engineering LaboratoryChongqing Academy of Chinese Materia MedicaChongqing 400065People’s Republic of China CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China

The genus Thuja is ideal for investigating the genetic basis of the East Asia-North America disjunction.The biogeographical background of the genus is debatable and an adaptive strategy is lacking.Through the analysis and mining of comparative transcriptomes,species differentiation and positively selected genes(PSGs)were identified to provide information for understanding the environmental adaptation strategies of the genus Thuja.De novo assembly yielded 44,397-74,252 unigenes of the five Thuja species with contig N50length ranging from 1,559 to 1,724 bp.Annotations revealed a similar distribution of functional categories among them.Based on the phylogenetic trees constructed using the transcriptome data,T.sutchuenensis was divided first,followed by T.plicata and T.occidentalis.The final differentiation of T.koraiensis and T.standishii formed a clade.Enrichment analysis indicated that the PSGs of the North American Thuja species were involved in plant hormone signal transduction and carbon fixation of photosynthetic organisms pathways.The PSGs of East Asian Thuja were related to phenolic,alkaloid,and terpenoid synthesis,important stress-resistant genes and could increase plant resistance to external environmental stresses.This study discovered numerous aroma synthetic-related PSGs including terpene synthase(TPS)genes and lipid phosphate phosphatase 2(LPP2),associated with the synthetic aroma of T.sutchuenensis.Physiological indicators,such as the contents of soluble sugars,total chlorophyll,total phenolics,and total flavonoids were determined,which are consistent with the PSGs enrichment pathways associated with adaptive strategies in the five Thuja species.The results of this study provide an important basis for future studies on conservation genetics.

关键词： Thuja species Comparative transcriptomes East Asia-North America disjunction Specific gene Positively selected gene

Development of Fixture Layout Optimization for Thin-Walled Parts:A Review

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 15-39页

作者： Changhui liu Jing Wang Binghai Zhou Jianbo Yu Ying Zheng Jianfeng Liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

An increasing number of researchers have researched fixture layout optimization for thin-walled part assembly during the past decades.However,few papers systematically review these researches.By analyzing existing literature,this paper summarizes the process of fixture layout optimization and the methods applied.The process of optimization is made up of optimization objective setting,assembly variation/deformation modeling,and fixture layout optimization.This paper makes a review of the fixture layout for thin-walled parts according to these three steps.First,two different kinds of optimization objectives are introduced.Researchers usually consider in-plane variations or out-of-plane deformations when designing objectives.Then,modeling methods for assembly variation and deformation are divided into two categories:Mechanism-based and data-based methods.Several common methods are discussed respectively.After that,optimization algorithms are reviewed systematically.There are two kinds of optimization algorithms:Traditional nonlinear programming and heuristic algorithms.Finally,discussions on the current situation are provided.The research direction of fixture layout optimization in the future is discussed from three aspects:Objective setting,improving modeling accuracy and optimization algorithms.Also,a new research point for fixture layout optimization is discussed.This paper systematically reviews the research on fixture layout optimization for thin-walled parts,and provides a reference for future research in this field.

关键词： Thin-walled parts Assembly quality Fixture layout optimization Modeling methods Optimization algorithms

Influence of volume compression on the unloading deformation behavior of red sandstone under damage-controlled cyclic triaxial loading

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1200-1212页

作者： Huaizhong liu Jianliang Pei Jianfeng Liu Mingli Xiao Li Zhuo Hongqiang Xie State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu610065China

A reasonable evaluation of unloading deformation characteristics is of great significance for the effective analysis of deformation and stability of surrounding rocks after underground excavation.In this study,the damage-controlled cyclic triaxial loading tests were conducted to investigate the pore compaction mechanism and its influences on the unloading deformation behavior of red sandstone,including Young’s modulus,Poisson’s ratio,volumetric strain,and irreversible strain.The experimental results show that the increases of volumetric and irreversible strains of rocks can be attributed to the compaction mechanism,which almost dominates the entire pre-peak deformation process.The unloading deformation consists of the reversible linear and nonlinear strains,and the irreversible strain under the influence of the porous grain structure.The pre-peak Young’s modulus tends to increase and then decrease due to the influence of the unloading irreversible strain.However,it hardly changes with the increasing volumetric strain compaction under the influence of reversible nonlinear strain.Instead,the initial unloading tangent modulus is highly related to the volumetric strain,and clearly reflects the compaction state of red sandstone.Furthermore,both the reversible nonlinear and irreversible unloading deformations are independent of confining pressure.This study is beneficial for the theoretical modeling and prediction of cyclic unloading deformation behavior of red sandstone.

关键词： Cyclic loading tests Compaction mechanism Volumetric strain Unloading tangent modulus Red sandstone

Electrolyte Engineering Toward High-Voltage Aqueous Energy Storage Devices

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Energy & Environmental Materials 2021年第3期4卷 302-306页

作者： jianfeng Tan Jinping liu School of Chemistry Chemical Engineering and Life Science and State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China State Center for International Cooperation on Designer Low-carbon&Environmental Materials and School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Aqueous electrochemical energy storage(EES)devices are highly safe,environmentally benign,and inexpensive,but their operating voltage and energy density must be increased if they are to efficiently power multifunctional electronics,new-energy cars as well as to be used in smart grids.This Minireview summarizes the key breakthroughs and progress in expanding the electrochemical stability window(ESW)of aqueous EES devices over the past five years.After briefly introducing the electrode engineering ways to widen ESW,we focus on four ground-breaking electrolyte engineering strategies and classify them into two kinds from the perspective of salts and exotic solutes/solvents.The widening degree toward ESW of these emerging electrolytes is compared and the universal fundamental mechanism relating to the interactions between limited water molecules and high-concentration salts(or large amounts of exotic solutes/solvents)is elucidated.Key challenges and perspectives for high-ESW electrolytes as well as recent advances in low-cost and other metal ion(sodium,potassium,zinc,etc.)-based electrolytes for expanding ESW are also outlined.

关键词： aqueous energy storage systems electrolyte engineering high voltage high-energy density water electrolysis

Coordination environments tune the activity of oxygen catalysis on single atom catalysts:A computational study

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Nano Research 2022年第4期15卷 3073-3081页

作者： Gaofan Xiao Ruihu Lu Jianfeng Liu Xiaobin Liao Zhaoyang Wang Yan Zhao State Key Laboratory of Silicate Materials for Architectures International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Designing highly efficient bifunctional electrocatalysts for oxygen reduction and evolution reaction(ORR/OER)is extremely important for developing regenerative fuel cells and metal-air batteries.Single-atom catalysts(SACs)have gained considerable attention in recent years because of their maximum atom utilization efficiency and tunable coordination environments.Herein,through density functional theory(DFT)calculations,we systematically explored the ORR/OER performances of nitrogencoordinated transition metal carbon materials(TM-N_(x)-C(TM=Mn,Fe,Co,Ni,Cu,Pd,and Pt;x=3,4))through tailoring the coordination environment.Our results demonstrate that compared to conventional tetra-coordinated(TM-N_(4)-C)catalysts,the asymmetric tri-coordinated(TM-N_(3)-C)catalysts exhibit stronger adsorption capacity of catalytic intermediates.Among them,Ni-N_(3)-C possesses optimal adsorption energy and the lowest overpotential of 0.29 and 0.28 V for ORR and OER,respectively,making it a highly efficient bifunctional catalyst for oxygen catalysis.Furthermore,we find this enhanced effect stems from the additional orbital interaction between newly uncoordinated d-orbitals and p-orbitals of oxygenated species,which is evidently testified via the change of d-band center and integral crystal orbital Hamilton population(ICOHP).This work not only provides a potential bifunctional oxygen catalyst,but also enriches the knowledge of coordination engineering for tailoring the activity of SACs,which may pave the way to design and discover more promising bifunctional electrocatalysts for oxygen catalysis.

关键词： single-atom catalysts density functional theory oxygen reduction reaction oxygen evolution reaction coordination environments

A review of the literature on randomized controlled trials of acupuncture and moxibustion in the treatment of chronic prostatitis/chronic pelvic-pain syndrome within 2016-2021

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Journal of Traditional Chinese Medical Sciences 2022年第3期9卷 222-229页

作者： Shiheng Wang Peijie Qin Fengxia Zhang Jianfeng Liu Institute for History of Medicine and Medical Literature China Academy of Chinese Medical SciencesBeijing100700China

Chronic prostatitis(CP)/chronic pelvic-pain syndrome(CPPS)is a common urinary-system disease with a high incidence in young and middle-aged men,seriously affecting patients'ability to work and their quality of life(Qo L).Western medicine(WM)has some limitations in treating CP/CPPS.Acupuncture is an ancient Chinese medical method that is commonly used to treat this condition and has a relatively good effect on it.Many randomized controlled trials(RCTs)on this subject have been published.For this study,we searched the China National Knowledge Infrastructure(CNKI),Chinese Science and Technology Periodical(VIP),Wanfang,Sino Med,and Pub Med databases for RCTs on acupuncture treatment of CP/CPPS in the last 5 years(2016/01/01-2021/12/01).In addition,we conducted analysis and research,aiming to summarize acupuncture treatment in CP/CPPS RCTs and the clinical efficacy,with the goal of providing clinical reference.A total of 466 related documents were retrieved in the search,and 62 articles were retained after screening.We obtained RCT information on acupuncture treatment of CP/CPPS.The results showed that several relevant clinical studies have been performed over the last 5 years and that acupuncture and moxibustion have better curative effect on CP/CPPS than WM.Due to the small number of included studies,more experimental evidence is needed to verify the clinical efficacy of acupuncture.

关键词： Acupuncture Filament needle Warm-needle moxibustion Electroacupuncture Chronic prostatitis Clinical Mechanism Literature search

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手术在鼻咽癌治疗中的地位

中华耳鼻咽喉头颈外科杂志 2022年第11期57卷 1347-1353页

作者：刘剑锋中日友好医院耳鼻咽喉头颈外科北京100029

鼻咽癌是一种发生于鼻咽上皮组织的恶性肿瘤, 放疗在其治疗中起重要作用, 而手术仅起辅助作用。但放疗存在一定失败率, 同时可能带来严重的并发症, 显著影响患者生活质量。随着内镜颅底外科技术的飞速发展, 很多中心开始重新审视并积极... 详细信息

鼻咽癌是一种发生于鼻咽上皮组织的恶性肿瘤, 放疗在其治疗中起重要作用, 而手术仅起辅助作用。但放疗存在一定失败率, 同时可能带来严重的并发症, 显著影响患者生活质量。随着内镜颅底外科技术的飞速发展, 很多中心开始重新审视并积极探索内镜手术在鼻咽癌治疗中的作用。本文将从以下3个方面总结手术在鼻咽癌治疗中的作用:复发或残存鼻咽癌的手术治疗、放疗后颅底放射性骨坏死的手术治疗以及内镜手术治疗原发性鼻咽癌的尝试。还需要进一步完善多中心、大样本、长期随访的临床试验, 基于循证医学证据, 推动鼻咽癌治疗模式的转变。

关键词：鼻咽癌治疗内镜手术循证医学证据长期随访放射性骨坏死临床试验放疗后恶性肿瘤

Individual Word Length Patterns for Fractional Factorial(Split-Plot)Designs

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Journal of Systems Science & Complexity 2023年第5期36卷 2082-2099页

作者： HAN Xiaoxue CHEN Jianbin YANG jianfeng liu Minqian School of Statistics and Data Science Qufu Normal UniversityQufu 273165China School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China School of Statistics and Data Science LPMC&KLMDASRNankai UniversityTianjin 300071China

Fractional factorial(FF)designs are commonly used for factorial experiments in many fields.When some prior knowledge has shown that some factors are more likely to be significant than others,Li,et al.(2015)proposed a new pattern,called the individual word length pattern(IWLP),which,defined on a column of the design matrix,measures the aliasing of the effect assigned to this column and effects involving other factors.In this paper,the authors first investigate the relationships between the IWLP and other popular criteria for regular FF designs.As we know,fractional factorial split-plot(FFSP)designs are important both in theory and practice.So another contribution of this paper is extending the IWLP criterion from FF designs to FFSP designs.The authors propose the IWLP of a factor from the whole-plot(WP),or sub-plot(SP),denoted by the I_w WLP and Is WLP respectively,in the FFSP design.The authors further propose combined word length patterns C_(w) WLP and Cs WLP,in order to select good designs for different cases.The new criteria C_(w) WLP and Cs WLP apply to the situations that the potential important factors are in WP or SP,respectively.Some examples are presented to illustrate the selected designs based on the criteria established here.

关键词： Effect hierarchy fractional factorial split-plot prior information regular design

Multiscale modeling of gas-induced fracturing in anisotropic clayey rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2091-2110页

作者： Jianxiong Yang Jianfeng Liu Zhengyuan Qin Xuhai Tang Houquan Zhang State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610042China School of Resources and Safety Engineering Wuhan Institute of TechnologyWuhan430073China School of Civil Engineering Wuhan UniversityWuhan430072China State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China

In the context of repositories for nuclear waste,understanding the behavior of gas migration through clayey rocks with inherent anisotropy is crucial for assessing the safety of geological disposal facilities.The primary mechanism for gas breakthrough is the opening of micro-fractures due to high gas pressure.This occurs at gas pressures lower than the combined strength of the rock and its minimum principal stress under external loading conditions.To investigate the mechanism of microscale mode-I ruptures,it is essential to incorporate a multiscale approach that includes subcritical microcracks in the modeling framework.In this contribution,we derive the model from microstructures that contain periodically distributed microcracks within a porous material.The damage evolution law is coupled with the macroscopic poroelastic system by employing the asymptotic homogenization method and considering the inherent hydro-mechanical(HM)anisotropy at the microscale.The resulting permeability change induced by fracture opening is implicitly integrated into the gas flow equation.Verification examples are presented to validate the developed model step by step.An analysis of local macroscopic response is undertaken to underscore the influence of factors such as strain rate,initial damage,and applied stress,on the gas migration process.Numerical examples of direct tension tests are used to demonstrate the model’s efficacy in describing localized failure characteristics.Finally,the simulation results for preferential gas flow reveal the robustness of the two-scale model in explicitly depicting gas-induced fracturing in anisotropic clayey rocks.The model successfully captures the common behaviors observed in laboratory experiments,such as a sudden drop in gas injection pressure,rapid build-up of downstream gas pressure,and steady-state gas flow following gas breakthrough.

关键词： Deep geological repositories Mode-I microcracks Time-dependent damage Fracturing process Anisotropic rock