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Diverse responses of fungal functional groups to desertification in forest soils of Pinus densata on the Chinese Tibetan plateau

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-11页

作者： Hua, Jiani Zhang, Jiangbao Song, Baohan Wang, Tianyi Li, Jingji yang, Nan mao, Lingfeng Nanjing Forestry Univ Coll Ecol & Environm Coinnovat Ctr Sustainable Forestry Southern China Lab Biodivers & Conservat Nanjing 210037 Peoples R China Chengdu Univ Technol Inst Ecol Resources & Landscape Architecture Chengdu 610059 Peoples R China

Rapid increase in desertification is an environmental concern, especially for the health and sustainability of ecosystems in changing climates. How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically important groups such as soil fungi functional groups. This study investigated variations in diversities of three soil fungi functional guilds (saprotrophic, symbiotic, pathogenic) and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense. The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi (mean relative abundance decreasing from 97.0% to 68.3%), in contrast to saprotrophic fungi (increasing from 2.7% to 25.7%) and pathogenic (from 0.3% to 5.9%). Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness, which was significantly lower in arid soils, and positively correlated with saprotrophic and pathogenic fungal alpha-diversity, which were abundant. Different community structures and regulators of the three fungi communities were observed, with pH, total phosphorus and ammonium (NH4+) as the main determinants. This study links the biotic and abiotic components during desertification and the interactions between them, and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a changing climate.

关键词： Desertification Fungal diversity Saprotrophs Ectomycorrhizal fungi Climate change MULTIPLE SEQUENCE ALIGNMENT MICROBIAL COMMUNITIES MYCORRHIZAL FUNGI PLANT DIVERSITY ENZYME-ACTIVITY ECTOMYCORRHIZAL PH ECOSYSTEM FRAMEWORK GRADIENT

Virtual source approach for maximizing resolution in high-penetration gamma-ray imaging

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Matter and Radiation at Extremes 2024年第3期9卷 19-30页

作者： Yuchi Wu Shaoyi Wang bin Zhu Yonghong Yan Minghai Yu Gang Li Xiaohui Zhang Yue yang Fang Tan Feng Lu Bi Bi Xiaoqin mao Zhonghai Wang Zongqing Zhao Jingqin Su Weimin Zhou Yuqiu Gu National Key Laboratory of Plasma Physics Laser Fusion Research CenterCAEPMianyangSichuan 621900China College of Physics Sichuan UniversityChengdu 610065China

High-energy gamma-ray radiography has exceptional penetration ability and has become an indispensable nondestructive testing(NDT)tool in various *** high-energy photons,point projection radiography is almost the only feasible imaging method,and its spatial resolution is primarily constrained by the size of the gamma-ray *** conventional industrial applications,gamma-ray sources are commonly based on electron beams driven by accelerators,utilizing the process of bremsstrahlung *** size of the gamma-ray source is dependent on the dimensional characteristics of the electron *** research has been conducted on various advanced accelerator technologies that have the potential to greatly improve spatial resolution in *** our investigation of laser-driven gamma-ray sources,a spatial resolution of about 90μm is achieved when the areal density of the penetrated object is 120 g/cm^(2).A virtual source approach is proposed to optimize the size of the gamma-ray source used for imaging,with the aim of maximizing spatial *** this virtual source approach,the gamma ray can be considered as being emitted from a virtual source within the convertor,where the equivalent gamma-ray source size in imaging is much smaller than the actual emission *** the basis of Monte Carlo simulations,we derive a set of evaluation formulas for virtual source scale and gamma-ray emission *** optimal conditions,the virtual source size can be as small as 15μm,which can significantly improve the spatial resolution of high-penetration imaging to less than 50μm.

关键词： resolution approach utilizing

Design and fabrication of self-suspending aluminum-plastic/semiconductor photocatalyst devices for solar energy conversion

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Journal of Environmental Sciences 2024年第2期136卷 615-625页

作者： Zhi-Ang Zhao Jingyun mao Chengjing Lu Shuangqiao yang Qingrong Qian Qinghua Chen Hun Xue Xiaoli Sun Min-Quan yang College of Environmental and Resource Sciences College of Carbon Neutral Modern IndustryFujian Key Laboratory of Pollution Control and Resource ReuseFujian Normal UniversityFuzhou 350007China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China

The design and synthesis of self-suspending photocatalyst device with easy recyclability is important for practical ***,this work utilizes aluminum-plastic package waste as raw material to prepare an aluminum-plastic supported TiO_(2)(AP-TiO_(2))photocatalyst device through 3D printing design and surface deposition method.A series of characterizations were carried out to explore the structure,morphology and performance of the AP-TiO_(2)*** UV light illumination,the AP-TiO_(2)-50 efficiently degrade 93.6%tetracycline hydrochloride(THC)after 4 hr,which increases by 8.3%compared with that of TiO_(2)powder suspension system with the same catalyst *** on it,AP-ZnO,AP-CdS,AP-g-C_3N_4and AP-Pt-TiO_(2)are also fabricated,and applied in photocatalytic degradation and hydrogen evolution,which all exhibit higher photoactivities than powder suspension *** work provides a new avenue for the fabrication of advanced recyclable photocatalyst ***,the work offers a novel sight for the high-value utilization of aluminum-plastic package waste,which has positive implications for environmental protection.

关键词： TiO_(2) Self-suspending Photocatalyst device Aluminum plastic

Demand and key technology for a LEO constellation as augmentation of satellite navigation systems

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Satellite Navigation 2024年第1期5卷 1-9页

作者： Yuanxi yang Yue mao Xia Ren Xiaolin Jia Bjiao Sun Xi’an Research Institute of Surveying and Mapping Xi’an710054ShaanxiChina State National Key Laboratory of Geo-Information Engineering Xi’an710054ShaanxiChina

A Low Earth Orbit(LEO)constellation augmenting satellite navigation is important in the future development of Global Navigation Satellite System(GNSS).GNSS augmented by LEO constellations can improve not only the accuracy of Positioning,Navigation,and Timing(PNT),but also the consistency and reliability of secure PNT *** paper mainly analyzes the diverse demands of different PNT users for LEO augmented GNSS,including the precision demand in real-time,the availability demand in special areas,the navigation signal enhancement demand in complex electromagnetic environments,and the integrity demand with high ***,the possible contributions of LEO constellations to PNT performance are analyzed from multiple aspects.A particular attention is paid to the special PNT user requirements that cannot be fulfilled with existing GNSS,such as the PNT service demand in the polar regions and the onboard GNSS orbit determination demand of some LEO *** key technologies to be considered in the constellation design,function realization,and payload development of the LEO-augmented navigation system are summarized.

关键词： Low earth orbit navigation constellation Accuracy augmentation Orbit determination Integrity

Mechanism of slag pellets sticking on the wall of reduction pot in magnesium production by Pidgeon process

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Journal of Magnesium and Alloys 2024年第6期12卷 2397-2412页

作者： Jilei Xu Jinhui Liu Dong Guo mao Chen Peixu yang Rongbin Li Shaojun Zhang School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Province Industrial Technology Research Institute of Resources and Materials Zhengzhou UniversityZhengzhou 450001China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

In the preparation of magnesium by Pidgeon process,the phenomenon slag pellets sticking on the wall of reduction pot always appear,and the glaze sticking on the inner wall of the reduction pot is difficult to *** mechanism of this phenomenon is studied in this work by X-ray fluorescence spectrometer(XRF)measurement,electron probe microanalyzer scanning(EPMA)analysis,differential scanning calorimetry(DSC)analysis,and thermodynamic *** main components of the glaze are MgO,Ca_(12)Al_(14)F_(2)O_(32),CaF_(2),CaO,and a small amount of Ca_(4)Si_(2)O_(7)F_(2).The solid-liquid transition temperature of Ca_(12)Al_(14)F_(2)O_(32)and CaF_(2)is close to the production temperature of Pidgeon process,which leads to the bonding between the slag pellets and the pot *** loss of CaF_(2)in glaze layer will reduce the total amount of liquid phase and increase the temperature at which Ca_(12)Al_(14)F_(2)O_(32)is completely transformed into liquid phase,which causes glaze layer sticking on the inner wall of the reduction pot.

关键词： Pidgeon process Glaze Ca_(12)Al_(14)F_(2)O_(32) CaF_(2) Solid-liquid transition

The protective role of prebiotics and probiotics on diarrhea and gut damage in the rotavirus-infected piglets

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1424-1448页

作者： Heng yang Xiangqi Fan Xiangbing mao bing Yu Jun He Hui Yan Jianping Wang Institute of Animal Nutrition Sichuan Agricultural UniversityKey Laboratory for Animal Disease-Resistance Nutrition of China Ministry of EducationKey Laboratory of Animal Disease-Resistant Nutrition and Feed of China Ministry of Agriculture and Rural AffairsKey Laboratory of Animal Disease-Resistant Nutrition of Sichuan ProvinceNo.211Gongpinghuimin RoadWenjiang DistrictChengduSichuan Province 611130People’s Republic of China

Rotavirus is one of the pathogenic causes that induce diarrhea in young animals, especially piglets, worldwide. However, nowadays, there is no specific drug available to treat the disease, and the related vaccines have no obvious efficiency in some countries. Via analyzing the pathogenesis of rotavirus, it inducing diarrhea is mainly due to disturb enteric nervous system, destroy gut mucosal integrity, induce intracellular electrolyte imbalance, and impair gut microbiota and immunity. Many studies have already proved that prebiotics and probiotics can mitigate the damage and diarrhea induced by rotavirus infection in hosts. Based on these, the current review summarizes and discusses the effects and mechanisms of prebiotics and probiotics on rotavirus-induced diarrhea in piglets. This information will highlight the basis for the swine production utilization of prebiotics and probiotics in the prevention or treatment of rotavirus infection in the future.

关键词： Diarrhea Piglet Prebiotics Probiotics Rotavirus

Conservation genomic investigation of an endangered conifer,Thuja sutchuenensis,reveals low genetic diversity but also low genetic load

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Plant Diversity 2024年第1期46卷 78-90页

作者： Tongzhou Tao Richard IMilne Jialiang Li Heng yang Shiyang Wang Sihan Chen Kangshan mao Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education&Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station College of Life ScienceSichuan UniversityChengduChina Institute of Molecular Plant Science School of Biological ScienceUniversity of EdinburghEdinburgh EH93BFUK College of Science Tibet UniversityLhasa 850000Xizang Autonomous RegionPR China

Endangered species generally have small populations with low genetic diversity and a high genetic *** sutchuenensis is an endangered conifer endemic to southwestern *** was once considered extinct in the wild,but in 1999 was ***,little is known about its genetic *** collected 67 individuals from five wild,isolated *** populations,and used 636,151 SNPs to analyze the level of genetic diversity and genetic load in *** to delineate the conservation units of ***,based on whole transcriptome sequencing data,as well as target capture sequencing *** found that populations of *** could be divided into three *** groups had low levels genetic diversity and were moderately genetically *** findings also indicate that *** suffered two severe bottlenecks around the Last Glaciation Period and Last Glacial *** Thuja species,*** presented the lowest genetic load and hence might have purged deleterious mutations efficiently through purifying ***,distribution of fitness effects analysis indicated a high extinction risk for *** lines of evidence identified three management units for *** *** possesses a low genetic load,low genetic diversity,suboptimal fitness,and anthropogenic pressures all present an extinction risk for this rare *** might also hold true for many endangered plant species in the mountains all over the world.

关键词： Sichuan Arborvitae Genetic load Deleterious mutations Demographic history Conservation genomics

Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence

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Biomedical and Environmental Sciences 2024年第2期37卷 146-156页

作者： LIAO Zhen Yu yang Shuo HU Song LIU Jia mao Yong Jun SUN Shu Qin Department of Geriatrics the Affiliated Hospital of Qingdao UniversityQingdao 266000ShandongChina Department of Critical Care Medicine the Affiliated Hospital of Qingdao UniversityQingdao 266000ShandongChina

Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were *** SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic *** multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)*** Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 *** of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased ***2 rs4586 and MMP-2 rs14070 exhibited the most significant *** CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS.

关键词： Vascular senescence Pulse wave velocity(PWV) Single nucleotide polymorphism(SNP) Matrix metalloproteinase 2(MMP-2) Extracellular matrix(ECM) Structural degradation Multifactor dimensionality reduction(MDR)

Optimization design of the hydro-pneumatic suspension system for high clearance self-propelled sprayer using improved MOPSO algorithm

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 109-122页

作者： Fan yang Yuefeng Du Changkai Wen Zhen Li Enrong mao Zhongxiang Zhu College of Engineering China Agricultural UniversityBeijing 100083China Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment China Agricultural UniversityBeijing 100083China

Large high clearance self-propelled sprayers were widely used in field plant protection due to their high-efficiency operation *** by the characteristics of field operations such as high power,heavy weight,high ground clearance,and fast operation speed,the comprehensive requirements for the ride comfort,handling stability and road friendliness of the sprayer were increasingly *** the present stage,the chassis structure of the high clearance selfpropelled sprayer that attaches great importance to the improvement of comprehensive performance still has the problems of severe bumps,weak handling performance and serious road damage in complex field ***,this paper proposes an optimization design method for hydro-pneumatic suspension system of a high clearance self-propelled sprayer based on the improved MOPSO(Multi-Objective Particle Swarm Optimization)algorithm,covering the entire process of configuration design,parameter intelligent optimization,and system verification of the high clearance self-propelled sprayer ***,chassis structure of the hydro-pneumatic suspension suitable for the high clearance self-propelled sprayer was designed,and a design method combining the improved MOPSO algorithm based on time-varying fusion strategy and adaptive update with the parameter optimization of hydro-pneumatic suspension based on this algorithm was proposed,and finally the software simulation and bench performance verification were carried *** results show that the optimized hydropneumatic suspension has excellent vibration reduction effect,and the body acceleration,suspension dynamic deflection and tire deflection were increased by 16.5%,9.9%and 0.9%respectively,compared with those before *** comprehensive performance of the hydro-pneumatic suspension designed in this study is better than that of the traditional suspension.

关键词： high clearance self-propelled sprayer vibration reduction hydro-pneumatic suspension MOPSO multi-objective optimization