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基于图学习的缺失脑网络生成及多模态融合诊断方法

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数据采集与处理 2024年第4期39卷 843-862页

作者：龚荣芳黄麟雅朱旗李胜荣南京航空航天大学数学学院南京211106 飞行器数学建模与高性能计算工信部重点实验室南京211106 南京航空航天大学人工智能学院南京211106 脑机智能技术教育部重点实验室南京211106

融合大脑结构和功能网络的多模态脑网络能够挖掘不同模态间的互补信息,有效提高癫痫等神经系统疾病的诊断准确率,在神经疾病诊断上具有优势。然而,由于多模态数据采集时间长、成本高,在实际应用中常面临模态缺失问题,导致可用数据量减少... 详细信息

融合大脑结构和功能网络的多模态脑网络能够挖掘不同模态间的互补信息,有效提高癫痫等神经系统疾病的诊断准确率,在神经疾病诊断上具有优势。然而,由于多模态数据采集时间长、成本高,在实际应用中常面临模态缺失问题,导致可用数据量减少,模型的诊断精度和泛化能力下降。针对某一模态数据完全缺失问题,提出了基于图学习与循环一致生成对抗网络(Cycle-consistent generative adversarial networks,CycleGAN)的图CycleGAN方法。该方法通过引入图卷积神经网络与图注意力机制等图学习方法捕捉脑网络不同脑区间的特征信息,强化生成框架对图形式脑网络的特征提取能力,实现脑结构网络与功能网络的相互生成。此外,针对目前较少利用诊断结果评估生成数据质量的情况,提出了一种融合真实脑网络与生成脑网络的多模态融合分类模型,以进一步评估生成脑网络的有效性。在癫痫数据集上的实验结果表明,图CycleGAN方法能够有效利用已有的模态信息,实现缺失脑网络的生成。

关键词：脑网络模态缺失图学习生成对抗网络模态补全癫痫诊断

松辽平原典型黑土区不同土壤结构的古气候背景与黑土成因机制

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地质通报 2024年第5期43卷 766-778页

作者：刘航李瑞红李胜荣侯红星秦天高远周业泽李明军中国地质调查局廊坊自然资源综合调查中心河北廊坊065000 中国地质大学(北京) 地质过程与矿产资源国家重点实验室北京100083 自然资源部地球化学探测技术重点实验室中国地质科学院地球物理地球化学勘查研究所河北廊坊065000

黑土成因机制研究是理解黑土形成演化过程的基础,更是加强黑土地保护和可持续利用的关键。以松辽平原典型黑土区吉林梨树县LZK-4钻孔为研究对象,基于粘土矿物学、元素地球化学、^(14)C、光释光测年等手段,重建了梨树县晚更新世中期以来... 详细信息

黑土成因机制研究是理解黑土形成演化过程的基础,更是加强黑土地保护和可持续利用的关键。以松辽平原典型黑土区吉林梨树县LZK-4钻孔为研究对象,基于粘土矿物学、元素地球化学、^(14)C、光释光测年等手段,重建了梨树县晚更新世中期以来的古气候演化序列,揭示不同土壤类型的古气候背景,解析了典型黑土的气候成因机制。结果表明:①研究区典型黑土形成于晚全新世,底界年龄为2452 cal.a BP;②LZK-4钻孔揭示了黑土层—灰白色粘土层—褐黄色粘土层的垂向结构,气候总体变化趋势由温湿向干冷转化;③研究区典型黑土主要形成于晚全新世寒冷干旱的气候条件。本研究有助于理解松辽平原梨树地区典型黑土的形成演化过程,为黑土资源的开发、利用和保护提供科学依据。

关键词：松辽平原粘土矿物元素地球化学古气候黑土成因环境地质调查工程

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Mineral chemistry and isotope geochemistry of pyrite from the Heilangou gold deposit, Jiaodong Peninsula, Eastern China

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Geoscience Frontiers 2014年第2期5卷 205-213页

作者： Yutong Yan Na Zhang shengrong li Yongsheng li Faculty of City and Environmental Science Xinyang Normal University State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences (Beijing) Heilongjiang Seismological Bureau

The Heilangou gold deposit is located in the northern QixiaePenglai gold belt, which is one amongst the three large gold belts in the eastern Shandong Province （Jiaodong Peninsula）. The ore body has formed within the Guojialing granite. In this study, we report the mineral chemistry of pyrite, as well as the S, Pb, and HeO isotope data of the Heilangou gold deposit. The chemical composition of pyrite in the Heilangou gold deposit indicates that the associated gold deposit is a typical magmatic hydrothermal one. The geochemical signatures and crystal structure of pyrite show that the ore-forming materials have been derived from the crust. The S isotope data of the pyrites from Heilangou show an overall range from 5.5 to 7.8＆amp;and an average of 6.7＆amp;. The S isotope data in this deposit are similar to those from the deposits in the Jiaodong gold belt. The Pb and S isotope variations are small in the Heilangou gold deposit. The 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios are 17.4653e17.5958, 15.5105e15.5746 and 38.0749e38.4361, respec-tively. These data plot between the lower crust and the orogenic belt. The Pb isotope data in the Heilangou gold deposit are similar to those in the linglong gold deposit. From the Qixia gold area （the liukou and Majiayao gold deposits） to the MupingeRushan gold belt （Rushan gold deposit） to the ZhaoeYe gold belt （the linglong, Sanshandao and Jiaojia gold deposits）, the 206Pb/204Pb ratios progressively increase. The DeO isotope data obtained from quartz separates suggest that the ore-forming fluid was similar to a mixture of magmatic and meteoric waters. These results suggest that the ore-forming elements were primarily from source fluids derived from the lower crust.

关键词： Heilangou gold deposits Pyrite Isotope geochemistry Genesis

Characteristics of heavy metal accumulation on fly ash-and sewage sludge-amended calcific soil

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Chinese Journal Of Geochemistry 2012年第2期31卷 181-186页

作者： NIU Huapeng li shengrong SHEN Junfeng YAO Meijuan College of Geosciences China University of Petroleum Beijing 102249 China State Key Laboratory of Geological Processes and Mineral Resources China University ofGeosciences Beijing 100083 China

Land disposal of fly ash(FA)and sewage sludge(SS)is a major problem due largely to their potentially harmful *** this paper,a potting experiment was performed to evaluate the effects on the plant growth and to discuss in particular the potential hazard to soils and plants according to the characteristics of heavy metal accumulation and migration when FA and SS are used as the amendments of calcific soil in a limestone mining area. The results showed that the application of FA-SS mixture is capable of accelerating the growth of plants and improving the biomass production at either 1:1 or 1:2 FA-SS mixture:soil(w/w).The highest yields were obtained at 1:1(w/w)mixing *** compared with the Element Background Values of Soils in China,the analysis on heavy metals indicated that the contents of Pb,Cr,Hg,Cd,As,Ni,Cu and Zn in the amended soils came up to the second-class environmental quality standards,only Hg and Cd showed significant *** the same time, though the metal concentrations in roots were higher than those for the control,the concentrations except Cu,Zn in shoots were *** all the heavy metal contents in the plants were substantially lower than the toxicity limits. The results indicated that the combined use of FA and SS at a rational rate of application should pose no danger to both soil and food chain based on the characteristics of the FS and SS,heavy metals and calcific soil.

关键词：土壤重金属积累特征污水污泥粉煤灰钙化修订植物生长重金属含量

Laser Ablation ICP-MS U-Pb Zircon Geochronology of Granitoids and Quartz Veins in the Shihu Gold Mine, Taihang Orogen, North China: Timing of Gold-mineralization and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1211-1224页

作者： CAO Ye li shengrong XIONG Xianxiao li Zhenzhen liU Xiaobin YAO Meijuan ZHANG Huafeng State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China General Institute of Chemical Geology Survey China Chemical Geology and Mine BureauBeijing 100013China School of Earth Science and Resources China University of GeosciencesBeijing 100083China

The Shihu gold deposit, situated in the Taihang Mesozoic orogen of the North China Craton （NCC）, is hosted by ductile-brittle faults within Archean metamorphic core complex. The deposit is characterized by gold-bearing quartz-polymetallic sulfides veins. The Mapeng granitoids stock and intermediate-basic dikes intruded the metamorphic basement rocks, and are spatially related to gold mineralization. Detailed laser ablation inductively coupled plasma mass spectrometry （LA ICP-MS） U-Pb zircon ages of the granitic rocks, dykes and mineralized quartz veins in the studied area reveal its magmatic and mineralized history. The mineralized quartz veins contain inherited zircons with ages of about 2.55 Ga and 1.84 Ga, probably coming from the basement. These two Precambrian events are coeval with those in other parts of the NCC. The Mapeng granitoid stock, the largest intrusion in the area, was emplaced at ca. 130 Ma, and is coeval with magmatic zircon populations from diorites and quartz diorite pophyrites in the same region. The ca. 130 Ma magmatism and gold mineralization were most likely related to an underplating event that took place in the Taihang orogen at Late Mesozoic. The timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. This episode is simultaneous with those in the eastern margin of NCC, indicative of a widespread late Yanshanian metallogenic event that was a response to the Early Cretaceous lithosphere in the eastern NCC, in which the mesothermal gold deposits were formed from similar tectono-magmatic environments.

关键词： zircon U-Pb geochronology Shihu gold deposit geodynamic setting North China Craton

Calcium carbonate nanoparticles promote osteogenesis compared to adipogenesis in human bone-marrow mesenchymal stem cells

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Progress in Natural Science:Materials International 2018年第5期28卷 598-608页

作者： Xiaoning li Xing Yang Xujie liu Wei He Qianli Huang shengrong li Qingling Feng School of Earth Science and Resources China University of Geosciences State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Graduate School at Shenzhen Tsinghua University School of Materials Science and Engineering University of Science and Technology Beijing Key Laboratory of Advanced Materials of Ministry of Education of China School of Materials Science and Engineering Tsinghua University

Rhombohedron-like and fusiform calcium carbonate nanoparticles were fabricated using a new method. Their geometry was controlled by varying the mixing speed and ratio of ethanol versus water in reaction system. The calcium carbonate nanoparticles(CCNPs) have slight effect on viability of human bone-marrow mesenchymal stem cells(hBMSCs) with dose-dependent and shape-dependent, but they can significantly promote osteogenic differentiation of hBMSCs in vitro by 10–37% increase of alkaline phosphatase(ALP) activity, 9–36% growth of collagen secretion and 1.13–1.83 folds upregulation of osteogenesis-related genes, even at lower dose ranges(5–20 μg/ml). The efficacity of promoting osteogenesis depends on the shape and dose of CCNPs. Furthermore,adipogenesis was inhibited by less accumulation of lipid droplets, lower triglyceride(TG) secretion and downregulation of adipogenesis-related genes. These findings improve the understanding of effects CCNPs on hBMSCs fate towards osteoblasts or adipocytes and have meaningful impact for combining use of CCNPs and hBMSCs in tissue engineering and regenerative medicine fields.

关键词： Human bone-marrow mesenchymal stem cells Calcium carbonate nanoparticles Osteogenesis Adipogenesis

Apatite fission track dating evidence for tectonic movement of Yarlung Zangbo Thrust Zone

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Chinese Science Bulletin 2002年第9期47卷 765-768页

作者： YUAN Wanming HOU Zengqian WANG Shicheng li shengrong Institute of High Energy Physics.Chinese Academy of Sciences Beijing 100080China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China China University of Geosciences Beijing 100083China

Fission track geological chronology is an effective method of study on tectonic movement of fault zone. Apatite fission track (AFT) dating analyses of 9-apatite and 4-zircon samples collected from Lhasa to Langkazi, -70-km-long in SN provide an understanding of the age and the uplifting of both sides of the Yarlung Zangbo Thrust Zone (YZTZ) in this work. The AFT ages range from-37 to 14 Ma, indicating the time of major tectono-thermal events, i.e. the continent-continent collision along the YZTZ. Based on the relationship between the AFT ages and the sample elevations, there were two tectonic active periods: -37-20 Ma and 20-14 Ma. In the first period the tectonic event did not bring on differential uplifting. Rapid differential uplifting with rapid cooling, resulting from thrusting, took place in the second period. The vertical displacement was -1020 m and total -2.9 km of overburden has been removed from the present-day surface since cooling below -110°C began. The maximum cooling and denudation

关键词： fission track dating thrusting thermal event uplifting Yarlung Zangbo Zone Tibet.

Apatite fission track dating evidence on the tectonization of Gangdese block, south Qinghai-Tibetan Plateau

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Chinese Science Bulletin 2002年第3期47卷 239-243页

作者： YUAN Wanming WANG Shicheng li shengrong YANG Zhiqiang Institute of High Energy Physics Chinese Acadeny of SciencesBeijing 100039China China University of Geosciences Beijing 100083China Exploration and Production Research Institute SINOPECBeijing100083China

This work makes the quantitative constrain on tectonizations of the Gangdese block, south Qinghai-Tibetan Plateau. Apatite fission track (AFT) dating analyses of 15 samples collected across the Gangdese block show that the Gangdese block went through two periods of tectonizations, during -37.2-18.5 Ma and 18.5 - 8.0 Ma in the south Gangdese block, and during -47.6-5.3 Ma and 5.3-0 Ma in the middle Gangdese block. Different upliftings did not take place in the first period and rapid uplifting occurred in the late period. Meantime, there are some differences be-tween the south and middle Gangdese block. Their uplifting rate is 180 m/Ma and 70 m/Ma respectively. The rapid up-lifting time in the middle Gangdese block lagged behind the time in the south Gangdese block. It is Chala-Jiacuo-Riduo fault zone that is similar to the Yarlung Zangbo fault zone in control of the tectonization.

关键词： tectonization fault zone fission track apatite uplifting and cooling Gangdese block.

Laser probe ^(40)Ar/^(39)Ar dating for quartz from auriferous quartz veins in the Shihu gold deposit,western Hebei Province,North China

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Chinese Journal Of Geochemistry 2010年第4期29卷 438-445页

作者： CAO Ye li shengrong ZHANG Huafeng AO Chong li Zhenzhen liU Xiaobin State Key Laboratory of Geological Processes and Mineral Resources China University ofGeosciences Beijing 100083 China School of Earth Science and Resources China University of Geosciences Beijing 100083 China Department of Earth Sciences Laurentian University Sudbury P3E2C6 Canada

The Shihu gold deposit is situated in the central shear zone of the Meso-Cenozoic Fuping metamorphic core complex in the middle-northern part of the Taihang *** kind of gold deposits named after 'Shihu type' widely occurs in this ***-bearing quartz veins are their most important industrial *** laser 40Ar/39Ar geochronology of the mineralized quartz veins in the study area reveals details of its tectono-magmatic *** 40Ar/39Ar ages for the quartz are between 134.4 Ma and 155.9 Ma with a mean age of 141±4 Ma on the isochron line and 139±7 Ma on the inverse isochron line,respectively,which is interpreted to be the best estimate of the crystalline age of the quartz *** gold mineralization was most likely related to an underplating event that took place in the northern part of the Taihang Mountain at ca.140 *** timing of gold mineralization in the area is similar to those observed in other major gold-producing provinces in the *** episode is simultaneous with those in the eastern NCC,indicative of a widespread late Yanshanian metallogenic event that was a response either to the subduction of the Izanagi-Pacific plate beneath eastern China or to the removal of the Early Cretaceous lithosphere in the eastern *** ore-forming material sources may be the Early Precambrian metamorphic basement,instead of intermediate-acid rock bodies and dykes.

关键词：含金石英脉激光探针中国东部金矿床河北省西部平均年龄成矿时间