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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China

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Plant Diversity 2024年第3期46卷 353-361页

作者： Jingya Zhang Cui Xiao Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang feng Keping ma Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.

关键词： Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits

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Climate change filtered out resource-acquisitive plants in a temperate grassland in Inner Mongolia,China

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Science China(Life Sciences) 2024年第2期67卷 403-413页

作者： Heying Jing Xingshuo Xiong feng jiang Xucai Pu Wenhong ma Daijiang Li Zhongling Liu Zhiheng Wang Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Department of Biological Sciences Louisiana State UniversityBaton RougeLA 70803USA

Global climate change has led to the decline of species and functional diversity in ecosystems,changing community composition and ecosystem functions.However,we still know little about how species with different resource-use strategies(different types of resource usage and plant growth of plants as indicated by the spectrum of plant economic traits,including acquisitive resource-use strategy and conservative resource-use strategy)would change in response to climate change,and how the changes in the diversity of species with different resource-use strategies may influence community-level productivity.Here,using long-term(1982–2017)observatory data in a temperate grassland in Inner Mongolia,we investigated how climate change had affected the species richness(SR)and functional richness(FRic)for the whole community and for species with different resource-use strategies.Specifically,based on data for four traits representing leaf economics spectrum(leaf carbon concentration,leaf nitrogen concentration,leaf phosphorus concentration,and specific leaf area),we divided 81 plant species appearing in the grassland community into three plant functional types representing resource-acquisitive,medium,and resource-conservative species.We then analyzed the changes in community-level productivity in response to the decline of SR and FRic at the community level and for different resource-use strategies.We found that community-level SR and FRic decreased with drying climate,which was largely driven by the decline of diversity for resource-acquisitive species.However,community-level productivity remained stable because resource-conservative species dominating this grassland were barely affected by climate change.Our study revealed distinctive responses of species with different resource-use strategies to climate change and provided a new approach based on species functional traits for predicting the magnitude and direction of climate change effects on ecosystem functions.

关键词： biodiversity ecological strategy functional diversity functional trait long-term change species diversity

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Proposing a machine learning approach to analyze and predict basic high-temperature properties of iron ore fines and its factors

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1082-1094页

作者： Qing-ke Sun Yao-zu Wang jian-liang Zhang Zheng-jian Liu Le-le Niu Chang-dong Shan Yun-fei ma Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic algorithms.First,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was compared.Then,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the model.The test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after optimization.The trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.

关键词： Iron ore Basic high-temperature property machine learning Random forest Genetic algorithm

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Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

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China Foundry 2024年第2期21卷 147-158页

作者： Ning Wang Kai ma Qiu-da Li Yu-dong Yuan Yan-chun Zhao Li feng School of materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals Lanzhou 730050China CNNC Nuclear Power Operation and management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting technology.The microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal testing.The results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the dendrite.manganese(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these areas.With an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then decreases.Similarly,the area fraction initially decreases and then increases.Additionally,the alloy’s strength and wear resistance decrease,while its plasticity increases.The Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

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Effect of low-degree astigmatism on the objective visual quality

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1086-1093页

作者： Ling-Ying Ye Shu-feng Li Jing-Jing Zuo Jin Li Hui-Xiang ma National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

关键词： low-degree astigmatism objective visual quality Optical Quality Analysis System

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Braille Character Segmentation Algorithm Based on Gaussian Diffusion

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Computers, materials & Continua 2024年第4期79卷 1481-1496页

作者： Zezheng Meng Zefeng Cai Jie feng Hanjie ma Haixiang Zhang Shaohua Li School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou310018China

Optical braille recognition methods typically employ existing target detection models or segmentation modelsfor the direct detection and recognition of braille characters in original braille images. However, these methodsneed improvement in accuracy and generalizability, especially in densely dotted braille image environments. Thispaper presents a two-stage braille recognition framework. The first stage is a braille dot detection algorithmbased on Gaussian diffusion, targeting Gaussian heatmaps generated by the convex dots in braille images. Thisis applied to the detection of convex dots in double-sided braille, achieving high accuracy in determining thecentral coordinates of the braille convex dots. The second stage involves constructing a braille grid using traditionalpost-processing algorithms to recognize braille character information. Experimental results demonstrate that thisframework exhibits strong robustness and effectiveness in detecting braille dots and recognizing braille charactersin complex double-sided braille image datasets. The framework achieved an F1 score of 99.89% for Braille dotdetection and 99.78% for Braille character recognition. Compared to the highest accuracy in existing methods,these represent improvements of 0.08% and 0.02%, respectively.

关键词： Computer vision image recognition optical braille recognition

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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao jian Zheng Jin Guo Yunbo Shi Hengzhen feng Jun Tang Jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped lattices.The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and analyzed.The target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent lattices.The proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k Hz.After the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target frequency.These results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

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Guiding function of positron emission tomographycomputed tomography examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 693-699页

作者： Xuan Zhang Qi-Han Guo Rui Liu Jing Li Ying-Chao Li jian-Min ma Beijing Ophthalmology and Visual Sciences Key Laboratory Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Tai’an City Central Hospital Qingdao UniversityTai’an 271000Shandong ProvinceChina

AIM:To explore the role of positron emission tomographycomputed tomography(PET-CT)examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma(OAML).METHODS:The general clinical data,postoperative PET-CT results,treatment regimens,and the prognosis of 21 histopathologically confirmed OAML patients between October 2017 and September 2021 were collected.Among the 21 patients,five patients underwent surgical treatment alone,13 patients underwent surgical treatment combined with radiotherapy,and three patients underwent surgical treatment combined with chemotherapy.RESULTS:The follow-up period ranged from 8 to 79mo,with four cases of recurrence and no deaths.Through PETCT examination,two patients exhibited both local ocular metabolic elevation and systemic metastasis,and one of these patients had cervical lymph node metastasis,while the other had submandibular and parotid gland metastasis.Nine patients showed only local ocular metabolic elevation,while 10 patients had no abnormal metabolic activity locally.CONCLUSION:PET-CT examination plays a crucial role in detecting residual lesions and recurrence following tumor resection,aiding in precise disease staging,and facilitating the development of personalized treatment plans,ultimately improving patient prognosis.

关键词： ocular adnexal mucosa associated lymphoid tissue lymphoma positron emission tomographycomputed tomography ocular tumors

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Plasma-assisted aerogel interface engineering enables uniform Zn2+ flux and fast desolvation kinetics toward zinc metal batteries

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Journal of Energy Chemistry 2024年第8期95卷 29-38页

作者： Zijian Xu Zhenhai Shi Zhan Chang Fan feng Zhuanyi Liu Dongkun Chu jianguo Ren Zi-feng ma Suli Chen Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material Engineering Jiangnan University Shanghai Electrochemical Energy Devices Research Center Department of Chemical Engineering Shanghai Jiao Tong University BTR New material Group Co. LTD.

The poor reversibility of Zn anodes induced by dendrite growth,surface passivation,and corrosion,severely hinders the practical applicability of Zn metal batteries.To address these issues,a plasmaassisted aerogel（PAG） interface engineering was proposed as efficient ion transport modulator that can simultaneously regulate uniform Zn2+flux and desolvation behavior during battery operation.The PAG with ordered mesopores acted as an ion sieve to homogenize Zn deposition and accelerate Zn2+flux,which is favorable for corrosion resistance and dendrite suppression.Importantly,the plasma-assisted aerogel with abundant hydrophilic groups can facilitate the desolvation kinetics of Zn2+due to the multiple hydrogen-bonding interaction with the activated water molecules,thus accelerating the Zn2+migration kinetics.Consequently,the Zn/Zn cell assembled with PAG-modified separator demonstrates stable plating and stripping behavior(over 1400 h at 1 ma cm-2) and high Coulombic efficiency(99.8% at1 ma cm-2after 1100 cycles),and the Zn‖MnO2full cell shows excellent long-term cycling stability and maintains a high capacity of 154.9 ma h g-1after 1000 cycles at 1 A g-1.This study provides a feasible approach for the large-scale fabrication of aerogel functionalized separators to realize ultra-stable Zn metal batteries.

关键词： Aerogel interface Dendrite growth Plasma Zn metal batteries Zn2+ migration kinetics

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Anti-tumor and apoptotic effects in vitro and in vivo of a traditional Chinese medicine prescription

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Chinese Medical Journal 2011年第21期124卷 3583-3587页

作者： FANG Luo WANG Zeng KONG Wei-yue feng jian-guo ma Sheng-lin LIN Neng-ming Laboratory of Clinical Pharmacy Zhejiang Cancer Hospital Hangzhou Zhejiang 310022 China

Background Zhongfei Mixture （ZM）, a traditional Chinese medicine, exploited from the clinical experience, has mainly been used for the treatment of advanced lung cancer since it was produced in 1983. However, little research has been conducted on its anti-tumor mechanism. In this study, we aimed to investigate the anti-tumor and apoptotic effects of ZM in vitro and in vivo. Methods The growth inhibition effect of ZM on A549 cells was evaluated by MTT assay. Morphological observation and clone forming tests were performed to determine the effect of ZM on cell viability. Cell cycle distribution and apoptosis were analyzed by flow cytometry. In addition, the in vivo anti-proliferation activity of ZM was evaluated using mice bearing Lewis lung carcinoma. Further, the apoptosis of cells in tumor tissue was determined by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling （TUNEL） assay, and the expression of Ki-67 protein in tumor tissues was anatyzed by En-Vision immuno-histochemistry staining. Results ZM exerted an obvious inhibitory effect on proliferation of A549 cells. It arrested A549 cells in G2-M phase and induced apoptosis. Compared with 3.02% and 5.32% in control group, the percentages of cells arrested in G2-M phase were 19.20% and 19.58% in 7.94 mg/ml ZM treated A549 cells at 24 hours and 48 hours. Moreover, the apoptosis rate increased from 0.18% to 18.01% after ZM treatment for 48 hours. ZM also significantly inhibited tumor growth in the tumor-implanted mice. Compared with saline control group, the effects of ZM showed significant tumor growth inhibition （P 〈0.05）. Furthermore, ZM could down-regulate the expression of Ki-67 in tumor tissue in mice bearing Lewis lung carcinoma. Conclusions Our results indicated that ZM has notable anti-tumor effect and the effects of ZM in moderate dose groups were superlative both in vitro and in vivo. The possible mechanism of ZM might be associated with arresting cell cycle in G2-M phase as well as down-regulating Ki-67 expression in tumor tissues

关键词： Zhongfei Mixture ki-67 apoptosis mechanism

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