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Data error propagation in stacked bioclimatic envelope models

Integrative Zoology 2024年第2期19卷 262-276页

作者： Xueyan LI Babak NAIMI peng gong Miguel B.ARAÚJO Guangdong Provincial Key Laboratory of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of ScienceGuangzhouChina ‘Rui Nabeiro’Biodiversity Chair CHANGE-MED InstituteUniversity ofÉvoraÉvoraPortugal Department of Geography and Department of Earth Sciences University of Hong KongHong KongChina Department of Biogeography and Global Change National Museum of Natural SciencesCSICMadridSpain

Stacking is the process of overlaying inferred species potential distributions for multiple species based on outputs of bioclimatic envelope models(BEMs).The approach can be used to investigate patterns and processes of species richness.If data limitations on individual species distributions are inevitable,but how do they affect inferences of patterns and processes of species richness?We investigate the influence of different data sources on estimated species richness gradients in China.We fitted BEMs using species distributions data for 334 bird species obtained from(1)global range maps,(2)regional checklists,(3)museum records and surveys,and(4)citizen science data using presence-only(Mahalanobis distance),presence-background(MAXENT),and presence–absence(GAM and BRT)BEMs.Individual species predictions were stacked to generate species richness gradients.Here,we show that different data sources and BEMs can generate spatially varying gradients of species richness.The environmental predictors that best explained species distributions also differed between data sources.Models using citizen-based data had the highest accuracy,whereas those using range data had the lowest accuracy.Potential richness patterns estimated by GAM and BRT models were robust to data uncertainty.When multiple data sets exist for the same region and taxa,we advise that explicit treatments of uncertainty,such as sensitivity analyses of the input data,should be conducted during the process of modeling.

关键词： richness patterns species distribution stacked bioclimatic envelope models uncertainty

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Study on creep deformation and energy development of underground surrounding rock under four‐dimensional support

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Deep Underground Science and Engineering 2024年第1期3卷 25-38页

作者： Zhanguo Ma Junyu Sun peng gong pengfei Yan Nan Cui Ruichong Zhang School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhouChina State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhouChina Department of Mining Engineering Colorado School of MinesGoldenUSA

There is an urgent need to develop optimal solutions for deformation control of deep high‐stress roadways,one of the critical problems in underground engineering.The previously proposed four‐dimensional support(hereinafter 4D support),as a new support technology,can set the roadway surrounding rock under three‐dimensional pressure in the new balanced structure,and prevent instability of surrounding rock in underground engineering.However,the influence of roadway depth and creep deformation on the surrounding rock supported by 4D support is still unknown.This study investigated the influence of roadway depth and creep deformation time on the instability of surrounding rock by analyzing the energy development.The elastic strain energy was analyzed using the program redeveloped in FLAC3D.The numerical simulation results indicate that the combined support mode of 4D roof supports and conventional side supports is highly applicable to the stability control of surrounding rock with a roadway depth exceeding 520 m.With the increase of roadway depth,4D support can effectively restrain the area and depth of plastic deformation in the surrounding rock.Further,4D support limits the accumulation range and rate of elastic strain energy as the creep deformation time increases.4D support can effectively reduce the plastic deformation of roadway surrounding rock and maintain the stability for a long deformation period of 6 months.As confirmed by in situ monitoring results,4D support is more effective for the long‐term stability control of surrounding rock than conventional support.

关键词： coal mines elastic strain energy four‐dimensional support large roadway depth long‐term stability control plastic deformation surrounding rock

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Deforestation in Latin America in the 2000s predominantly occurred outside of typical mature forests

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The Innovation 2024年第3期5卷 88-98页

作者： Zhiyu Zhang Wenjian Ni Shaun Quegan Jingming Chen peng gong Luiz Carlos Estraviz Rodriguez Huadong Guo Jiancheng Shi Liangyun Liu Zengyuan Li Yating He Qinhuo Liu Yosio Shimabukuro Guoqing Sun Key Laboratory of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China Chinal of Mathematics and Statistics University of SheffieldSheffield S37RHUK Department of Geography and Program in Planning University of TorontoTorontoON M5S 3G3Canada Department of Earth Sciences and Department of Geography University of Hong KongHong KongChina Forest Science Department Luiz de Queiroz College of AgricultureUniversity of São PauloAv.Pádua Dias11Piracicaba 13418-900Brazil National Space Science Center Chinese Academy of SciencesBeijing 100190China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China Research Institute of Forest Policy and Information Chinese Academy of ForestryBeijing 100091China Remote Sensing Department National Institute for Space Research(INPE)Av.dos Astronautas 1758São Josédos Campos 12227-010Brazil Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA

The role of tropical forests in the global carbon budget remains controversial,as carbon emissions from deforestation are highly uncertain.This high uncertainty arises from the use of either fixed forest carbon stock density or maps generated from satellite-based optical reflectance with limited sensitivity to biomass to generate accurate estimates of emissions from deforestation.New space missions aiming to accurately map the carbon stock density rely on direct measurements of the spatial structures of forests using lidar and radar.We found that lost forests are special cases,and their spatial structures can be directly measured by combining archived data acquired before and after deforestation by space missions principally aimed at measuring topography.Thus,using biomass mapping,we obtained new estimates of carbon loss from deforestation ahead of forthcoming space missions.Here,using a high-resolution map of forest loss and the synergy of radar and lidar to estimate the aboveground biomass density of forests,we found that deforestation in the 2000s in Latin America,one of the severely deforested regions,mainly occurred in forests with a significantly lower carbon stock density than typical mature forests.

关键词： forest Latin lidar

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Elevational distribution of forests and its spatiotemporal dynamics in subtropical China from 2000 to 2019

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Science China Earth Sciences 2024年第8期67卷 2563-2582页

作者： Zhencan ZHENG Liuwen ZHUANG Guofang MIAO Han LIU Zhiqiang CHENG Wenyu LI Rong SHANG peng gong Jing Ming CHEN Institute of Geography Fujian Normal University Key Laboratory of Humid Subtropical Eco-Geographical Process (Ministry of Education) Fujian Normal University School of Geographical Sciences Fujian Normal University National Land Consolidation Center Ministry of Natural Resources Key Laboratory of Land Consolidation and Rehabilitation Ministry of Natural Resources Key Laboratory of Digital Mapping and Land Information Application Ministry of Natural Resources Department of Geography & Planning University of Toronto Department of Geography The University of Hong Kong

The subtropical region of China possesses abundant forest resources and features a mountainous terrain. Under the implementation of policies such as natural forest protection, the Grain for Green Project, and other initiatives since the beginning of the 21st century, coupled with climate change, the forest resources in this region have undergone significant changes compared to historical periods. In addition, forest resources distributing mainly in mountainous areas also implies that these changes may vary significantly with elevation. To explore the spatiotemporal dynamics of forest distribution in subtropical China since 2000,especially the trend of changes with elevation, we analyzed the data from two land cover products focusing on forest cover and forest types. We used a hierarchical approach, in which coarse-classification forest cover data with relatively small uncertainties impose constraints on forest type data with larger uncertainties, to achieve a reasonable balance between obtaining more details and reducing data uncertainty. We first divided the forest cover data into ‘unchanged' and ‘changed' categories. With the constraints by the forest cover results, we further analyzed the ‘unchanged' and ‘changed' forest types. The results indicated that,since the implementation of ecological engineering and management policies, 54% of the area in the subtropical region had maintained unchanged forest cover attributes over the past 20 years, which implied the good state of ecological environment. The results also showed that dynamic conversions existed in the long term between forests and lands for essential production needs like croplands. The elevational variations of forest cover suggested that the dominant changes came from the conversion between forests and croplands in low-elevation regions below 700 m, the conversion between forests and shrublands in mid-elevation regions of 700–1500 m, and the conversion between forests and grasslands in high-elevation regions above 2000 m. In the regions with unchange

关键词： Subtropical China Land cover Forest cover Forest type Elevational distribution

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Unusual substructure conformations observed in crystal structures of a dicistrovirus RNA-dependent RNA polymerase suggest contribution of the N-terminal extension in proper folding

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Virologica Sinica 2023年第4期38卷 531-540页

作者： Xiang Fang Guoliang Lu Yanchun Deng Sa Yang Chunsheng Hou peng gong Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan430207China Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangsha410205China University of Chinese Academy of Sciences Beijing100049China Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing100193China Hubei Jiangxia Laboratory Wuhan430207China

The Dicistroviridae is a virus family that includes many insect pathogens.These viruses contain a positive-sense RNA genome that is replicated by the virally encoded RNA-dependent RNA polymerase(RdRP)also named 3D^(pol).Compared with the Picornaviridae RdRPs such as poliovirus(PV)3D^(pol),the Dicistroviridae representative Israeli acute paralysis virus(IAPV)3D^(pol) has an additional N-terminal extension(NE)region that is about 40-residue in length.To date,both the structure and catalytic mechanism of the Dicistroviridae RdRP have remain elusive.Here we reported crystal structures of two truncated forms of IAPV 3D^(pol),namelyΔ85 andΔ40,both missing the NE region,and the 3D^(pol) protein in these structures exhibited three conformational states.The palm and thumb domains of these IAPV 3D^(pol) structures are largely consistent with those of the PV 3D^(pol) structures.However,in all structures,the RdRP fingers domain is partially disordered,while different conformations of RdRP substructures and interactions between them are also present.In particular,a large-scale conformational change occurred in the motif B-middle finger region in one protein chain of theΔ40 structure,while a previously documented alternative conformation of motif A was observed in all IAPV structures.These experimental data on one hand show intrinsic conformational variances of RdRP substructures,and on the other hand suggest possible contribution of the NE region in proper RdRP folding in IAPV.

关键词： Israeli acute paralysis virus(IAPV) Poliovirus RNA-dependent RNA polymerase(RdRP) Crystal structure Catalytic motif

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Microstructural formation and mechanical performance of friction stir double-riveting welded Al-Cu joints

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Chinese Journal of Aeronautics 2023年第8期36卷 454-471页

作者： Shude JI Zhiqing ZHANG peng gong Hua LIU Xiao CUI Yewei ZHANG College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China

A novel friction stir double-riveting welding(FSDRW) technology was proposed in order to realize the high-quality joining of upper aluminum(Al) and lower copper(Cu) plates,and this technology employed a Cu column as a rivet and a specially designed welding tool with a large concave-angle shoulder. The formations, interfacial characteristics, mechanical properties and fracture features of Al/Cu FSDRW joints under different rotational velocities and dwell times were investigated. The results showed that the well-formed FSDRW joint was successfully obtained.The cylindrical Cu column was transformed into a double riveting heads structure with a Cu anchor at the top and an Al anchor at the bottom, thereby providing an excellent mechanical interlocking.The defect-free Cu/Cu interface was formed at the lap interface due to the sufficient metallurgical bonding between the Cu column and the Cu plate, thereby effectively inhibiting the propagation of crack from the intermetallic compound layer at the lap interface between the Al and Cu plates. The tensile shear load of joint was increased first and then decreased when the rotational velocity and dwell time of welding tool increased, and the maximum value was 5.52 k N. The FSDRW joint presented a mixed mode of ductile and brittle fractures.

关键词： Dissimilar Al/Cu metals Friction stir double-riveting welding,Mechanical interlocking Mechanical properties Metallurgical bonding

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Experimental study of the dynamic mechanical responses and failure characteristics of coal under true triaxial confinements

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International Journal of Mining Science and Technology 2023年第6期33卷 761-772页

作者： Zhanguo Ma pengfei Yan Shixing Cheng peng gong Fuzhou Qi Jianguo Wang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

Investigations on the dynamic mechanical properties and failure mechanisms of coal under in-situ stress is essential for the prevention of dynamic disasters in deep coal mines.Thus,a modified true triaxial Hopkinson bar was employed to explore the dynamic mechanical behaviors of coal at different confining pressures(0–20 MPa)and strain rates(40–220 s^(-1)).The results show that the dynamic peak stress is positively correlated with lateral static pre-stressσy andσz,but negatively correlated with axial static prestressσx.At approximate strain rates,increasing the lateral static pre-stress facilitates increasing the dynamic peak stress,but the minimum lateral static pre-stress is the primary factor limiting a significant increase in dynamic peak stress of coal.Furthermore,the dynamic differential stress is linearly related to the logarithm of strain rate,and the peak strain varies linearly with strain rate.However,there is no significant correlation between confining pressure and peak strain.Moreover,X-ray CT images and photographic fracture observations of coal samples show the failure patterns under uniaxial and triaxial conditions are splitting failure and shear failure,respectively.The device provides a viable approach for fully comprehending the dynamic mechanical behaviors of rock-like material in complex stress conditions.

关键词： Coal True triaxial SHPB test Dynamic mechanical properties Failure characteristics

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Clinical characteristics of peripapillary hyperreflective ovoid mass-like structures in myopic children

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1292-1299页

作者： Lu Zhang Zuo-Hui-Zi Yi Xuan Jiang gong-peng Sun Fang Zhao Li Zhang Yi Xiang Chang-Zheng Chen Department of Ophthalmology the Central Hospital of WuhanTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430014Hubei ProvinceChina Eye Center Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina

AIM:To describe the characteristics of peripapillary hyperreflective ovoid mass-like structure(PHOMS)in myopic children and to investigate factors associated with PHOMS.METHODS:This retrospective observational study included 101 eyes of 101 children(age≤17y)with myopia.All included patients underwent comprehensive clinical examination.Optic nerve canal parameters,including disc diameter,optic nerve head(ONH)tilt angle,and border tissue angle were measured using serial enhanced-depth imaging spectral-domain optical coherence tomography(EDI-OCT).Based on the optic disc drusen consortium’s definition of PHOMS,eyes were classified as PHOMS group and non-PHOMS group.PHOMS was categorized according to height.RESULTS:Sixty-seven(66.3%)eyes were found with PHOMS.Small PHOMS could only be detected by optical coherence tomography(OCT).Medium PHOMS could be seen with blurred optic disc borders corresponding to OCT.The most frequent location of PHOMS was at the nasosuperior(91%,61 of 67 eyes)to ONH disc.The axial length and spherical equivalent were more myopic in the PHOMS group than in the non-PHOMS group(both P<0.001).ONH tilt angle was also significantly greater in PHOMS group than in non-PHOMS group[8.90(7.16-10.54)vs 3.93(3.09-5.25),P<0.001].Border tissue angle was significantly smaller in PHOMS group than in non-PHOMS group[29.70(20.90-43.81)vs 45.62(35.18-60.45),P<0.001].In the multivariable analysis,spherical equivalent(OR=3.246,95%CI=1.209-8.718,P=0.019)and ONH tilt angle(OR=3.275,95%CI=1.422-7.542,P=0.005)were significantly correlated with PHOMS.There was no disc diameter associated with PHOMS.In the linear regression analysis,border tissue angle was negatively associated with PHOMS height(β=-2.227,P<0.001).CONCLUSION:PHOMS is associated with optic disc tilt and optic disc nasal shift in myopia.Disc diameter is not a risk factor for PHOMS.The changes in ONH caused by axial elongation facilitated an understanding of the mechanism of PHOMS.

关键词： peripapillary hyperreflective ovoid masslike structure myopia optic disc edema enhanced-depth imaging spectral-domain optical coherence tomography

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The two-stage interaction of Ebola virus VP40 with nucleoprotein results in a switch from viral RNA synthesis to virion assembly/ budding

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Protein & Cell 2022年第2期13卷 120-140页

作者： Linjuan Wu Dongning Jin Dan Wang Xuping Jing peng gong Yali Qin Mingzhou Chen State Key Laboratory of Virology and Modern Virology Research Center College of Life SciencesWuhan UniversityWuhan 430072China Wuhan Institute of Virology Chinese Academy of SciencesWuhan 430071China

Ebola virus(EBOV)is an enveloped negative-sense RNA virus and a member of the filovirus family.Nucleoprotein(NP)expression alone leads to the formation of inclusion bodies(IBs),which are critical for viral RNA synthesis.The matrix protein,VP40,not only plays a critical role in virus assembly/budding,but also can regulate transcription and replication of the viral genome.However,the molecular mechanism by which VP40 regulates viral RNA synthesis and virion assembly/budding is unknown.Here,we show that within IBs the N-terminus of NP recruits VP40 and is required for VLP-containing NP release.Furthermore,we find four point mutations(L692A,P697A,P698A and W699A)within the C-terminal hydrophobic core of NP result in a stronger VP40–NP interaction within IBs,sequestering VP40 within IBs,reducing VP40–VLP egress,abolishing the incorporation of NC-like structures into VP40–VLP,and inhibiting viral RNA synthesis,suggesting that the interaction of N-terminus of NP with VP40 induces a conformational change in the C-terminus of NP.Consequently,the C-terminal hydrophobic core of NP is exposed and binds VP40,thereby inhibiting RNA synthesis and initiating virion assembly/budding.

关键词： Ebola virus nucleoprotein matrix protein two-stage interaction RNA synthesis nucleocapsid assembly/budding

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CO_(2) reduction with coin catalyst

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Nano Research 2022年第5期15卷 3859-3865页

作者： Taishi Xiao Can Tang Hongbin Li Tong Ye Kun Ba peng gong Zhengzong Sun Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200433China School of Microelectronics and State Key Laboratory of ASIC and System Fudan UniversityShanghai 200433China

Most organic commodity chemicals are derived from fossil carbon resources.The dependency is so immense that it is difficult to compensate for the accompanying carbon footprint with current technology and chemical infrastructure.To mitigate the future fossil fuel usage,it is crucial to explore alternative chemical pathways,which are both sustainable and suitable for large-scale productions.Here we demonstrate a closed-loop carbon-neutral chemical route,using standard coin catalyst,to produce high concentrated formate and formic acid.The catalyst's Faradaic efficiency(FE)of formate is~95.3% with great durability.The chemicals are not only synthesized but also purified and utilized in zero-carbon scenarios.We successfully harvested 45%formate salt and 86.2% formic acid,for applications like anti-freezing reagent and green liquid fuel to power the fuel-cell vehicles.

关键词： closed-loop lifecycle electrocatalysis coin catalyst

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