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A preliminary study of the weathering mechanism of fossilized Cretaceous Hamipterus bones

Science China Earth Sciences 2021年第3期64卷 458-469页

作者： Ying LI wugan luo Yimin YANG Shunxing JIANG Xiaolin WANG Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing100044China Department of Archaeology and Anthropology University of Chinese Academy of SciencesBeijing100049China CAS Center for Excellence in Life and Paleoenvironment Beijing100044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing100049China

The discovery of Hamipterus tianshanensis had important scientific significance because three-dimensional preserved fossils can provide unique information about the reproduction,development,and evolution of pterosaurs.However,the pterosaur fossils exhibited violent weathering,including noticeable cracking and spalling,since the preservation environment changed dramatically after excavation,which severely influenced the preservation of these fossils and the scientific research conducted on them.To determine the weathering mechanism of these fossil bones,the samples were analyzed using X-ray fluorescence(XRF),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS).The results indicate that calcite is the main mineral in the hollow bones,but it is mixed with a small amount of other minerals,such as quartz,feldspar,and other debris particles.Moreover,the main component of the pterosaur bones is hydroxyapatite,and carbonate has substituted for some of the phosphate(B-type carbonated apatite)in the fossil bones.A small amount of calcite and manganese oxides has precipitated in the vascular canals.The phosphate crystallinity index(PCI)is 4.17.These results indicate that the fossils have undergone severe diagenesis.Apart from these alterations,the fossil bones have high contents of anions and cations such as Cl^(-),NO_(3)^(-),SO_(4)^(2-),Na^(+),and Ca^(2+),and the total content of soluble salts is 35584.41μg g^(-1).Based on these results,it is inferred that the weathering mechanism of the fossil bones is as follows.First,the fragile hollow bones cracked easily because of the enormous thermal stress caused by the dramatic temperature changes in the Gobi Desert and the differences in the thermal expansion coefficients(TEC)of the surrounding rocks,the fossil bones,and the different fillers.Second,a large amount of stress is generated by salt crystallization when the temperature and humidity change,and the pterosaur fossils will be damaged

关键词： Hamipterus fossil weathering hydroxyapatite coefficient of thermal expansion Xinjiang

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早期锡青铜冶炼工艺的思考与模拟实验

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南方文物 2022年第5期 143-151页

作者：马丁王昌燧罗武干中国科学院大学考古学与人类学系

冶金作为人类历史上的一项重要进步,一直是历史学研究的热点。关于长期争论的冶金单一起源和多地起源问题,近年来欧亚大陆早期冶金技术多样性的发现以及早期简单冶金技术的揭示,致使多地起源观点更被关注。受早期黄铜冶炼工艺等研究的启... 详细信息

冶金作为人类历史上的一项重要进步,一直是历史学研究的热点。关于长期争论的冶金单一起源和多地起源问题,近年来欧亚大陆早期冶金技术多样性的发现以及早期简单冶金技术的揭示,致使多地起源观点更被关注。受早期黄铜冶炼工艺等研究的启示,本研究利用模拟实验并结合测试分析,探讨了早期锡青铜低温冶炼工艺的可行性。使用坩埚、马弗炉等工具,在650~950℃的温度下,以木炭为还原剂,冶炼孔雀石与锡石的混合物,并进而重熔冶炼产物。利用X射线荧光、X射线衍射、金相分析等方法观察、测试相关冶炼产物,其结果表明,冶炼温度达到700℃左右即可得到海绵状铜块。在930℃左右直接冶炼孔雀石和锡石的混合物,可得到有实用价值的锡青铜块。在不超过1000℃的温度下,能够将小块金属融合成锡青铜锭乃至铜刀坯料,金相组织可见α固溶体树枝晶及α+δ共析体,符合铜锡合金铸造组织特征。本项工作表明,在浇注青铜工艺成熟之前,有可能存在通过类似早期黄铜固态还原工艺冶炼获得锡青铜,期望这一推测能对冶金起源探索有所裨益。

关键词：锡青铜冶炼模拟实验固态还原

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秦并蜀的铜冶金考古解读：以成都出土烟荷包钺为例

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中国科技史杂志 2022年第4期43卷 495-506页

作者：王睿哲王宁李佩杨弢罗武干中国科学院古脊椎动物与古人类研究所中国科学院脊椎动物演化与人类起源重点实验室中国科学院大学人文学院考古学与人类学系成都文物考古研究院

众多历史及考古学者都对秦并蜀这一重要历史事件进行了深入研究，然而，罕见从铜冶金考古视角对秦并蜀进行解读的工作。故迄今我们并不清楚秦并蜀这一重要历史事件对蜀地青铜手工业是否产生了影响及其具体的影响方式如何。为了探讨此问... 详细信息

众多历史及考古学者都对秦并蜀这一重要历史事件进行了深入研究，然而，罕见从铜冶金考古视角对秦并蜀进行解读的工作。故迄今我们并不清楚秦并蜀这一重要历史事件对蜀地青铜手工业是否产生了影响及其具体的影响方式如何。为了探讨此问题，本文利用X光成像、合金成分及金相显微组织等分析方法，对成都地区出土9件战国中期至西汉早期铜钺进行系统研究。结果显示，秦并蜀前铜钺的锡含量在12%—17%之间，铅含量在0%—10%之间，其范铸成型后又经过热锻等形变加工处理，且銎部与刃部的铸后加工处理方式存在差异；而秦并蜀后铜钺的锡含量为3%—13%,铅含量为7%—23%,其铸造过程中多使用垫片，且成型后不再进行热加工与冷加工。可见，秦并蜀前后铜钺的合金配比、加工工艺及铸造技术都发生了转变。本文还进一步分析了产生这种变化的原因。

关键词：秦并蜀铜钺 X光成像成分分析金相

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Biological Interaction and Imaging of Ultrasmall Gold Nanoparticles

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Nano-Micro Letters 2024年第3期16卷 69-98页

作者： Dongmiao Sang Xiaoxi luo Jinbin Liu Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China

Ultrasmall gold nanoparticles(AuNPs)typically includes atomically precise gold nanoclusters(AuNCs)and AuNPs with a core size below 3 nm.Serving as a bridge between small molecules and traditional inorganic nanoparticles,the ultrasmall AuNPs show the unique advantages of both small molecules(e.g.,rapid distribution,renal clearance,low non-specific organ accumulation)and nanoparticles(e.g.,long blood circulation and enhanced permeability and retention effect).The emergence of ultrasmall AuNPs creates significant opportunities to address many challenges in the health field including disease diagnosis,monitoring and treatment.Since the nano–bio interaction dictates the overall biological applications of the ultrasmall AuNPs,this review elucidates the recent advances in the biological interactions and imaging of ultrasmall AuNPs.We begin with the introduction of the factors that influence the cellular interactions of ultrasmall AuNPs.We then discuss the organ interactions,especially focus on the interactions of the liver and kidneys.We further present the recent advances in the tumor interactions of ultrasmall AuNPs.In addition,the imaging performance of the ultrasmall AuNPs is summarized and discussed.Finally,we summarize this review and provide some perspective on the future research direction of the ultrasmall AuNPs,aiming to accelerate their clinical translation.

关键词： Ultrasmall gold nanoparticle Cellular interaction Organ interaction Tumor interaction Bioimaging

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Single-cell RNA sequencing in juvenile idiopathic arthritis

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Genes & Diseases 2024年第2期11卷 633-644页

作者： Xiwen luo Xuemei Tang Department of Rheumatology and Immunology Children’s Hospital of Chongqing Medical UniversityChongqing 400014China Chongqing Key Laboratory of Child Infection and Immunity Ministry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren's Hospital of Chongqing Medical UniversityChongqing 400014China

Juvenile idiopathic arthritis (JIA) is one of the most common chronic inflammatory rheumatic diseases in children,with onset before age 16 and lasting for more than 6 weeks.JIA is a highly heterogeneous condition with various consequences for health and quality of life.For some JIA patients,early detection and intervention remain challenging.As a result,further investigation of the complex and unknown mechanisms underlying JIA is required.Advances in technology now allow us to describe the biological heterogeneity and function of individual cell populations in JIA.Through this review,we hope to provide novel ideas and potential targets for the diagnosis and treatment of JIA by summarizing the current findings of single-cell RNA sequencing studies and understanding how the major cell subsets drive JIA pathogenesis.

关键词： Juvenile idiopathic arthritis Macrophage Macrophage activation syndrome Monocyte Single-cell RNA sequencing Synoviocyte T cell

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Precision regulation of plant aromatic amino acid homeostasis

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Science China(Life Sciences) 2024年第6期67卷 1316-1317页

作者： Jie luo Yazhouwan National Laboratory(YNL) Sanya 572025China School of Breeding and Multiplication(Sanya Institute of Breeding and Multiplication) Hainan UniversitySanya 572025China

The aromatic amino acids(AAAs)phenylalanine(Phe),tyrosine(Tyr),and tryptophan(Trp)are not only building blocks of proteins,but also precursors of numerous primary and specialized metabolites(Schenck and Maeda,2018).For instance,Trp is a precursor of the phytohormone auxin and the plant defense compounds indole glucosinolates,while Phe serves as a precursor of lignin,coumarin and flavonoids.Some plant natural products such as morphine and vitamin E are derived from Tyr,and have been employed in human medicine and nutrition(Schenck and Maeda,2018;Wu et al.,2022;Yokoyama et al.,2021).

关键词： aromatic instance coumarin

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Microbes in mass extinction: an accomplice or a savior?

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National Science Review 2024年第1期11卷 12-15页

作者： Genming luo Deng Liu Hao Yang China University of Geosciences (Wuhan) State Key Laboratory of Geobiology and Environmental Geology

Microbes include various types of organisms that are invisible to the naked eye,e.g. bacteria, archaea and microeukaryotes. Although the precise number remains largely unknown, microbes are recognized as the unseen majority of our biosphere [1]. As a group of organisms classified by body size, microbes cover a considerable spectrum of metabolisms,

关键词： AFTERMATH

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Large language model and domain-specific model collaboration for smart education

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 333-341页

作者： Yawei luo Yi YANG School of Software Technology Zhejiang UniversityNingbo 315048China College of Computer Science and Technology Zhejiang UniversityHangzhou 310027China

In this paper,we introduce the large language model and domain-specific model collaboration(LDMC)framework designed to enhance smart education.The LDMC framework leverages the comprehensive and versatile knowledge of large domain-general models,combines it with the specialized and disciplinary knowledge from small domainspecific models(DSMs),and incorporates pedagogy knowledge from learning theory models.This integration yields multiple knowledge representations,fostering personalized and adaptive educational experiences.We explore various applications of the LDMC framework in the context of smart education.

关键词： smart language knowledge

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Cell replacement with stem cell-derived retinal ganglion cells from different protocols

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Neural Regeneration Research 2024年第4期19卷 807-810页

作者： Ziming luo Kun-Che Chang Spencer Center for Vision Research Byers Eye InstituteStanford University School of Medicine Department of Ophthalmology Louis J.Fox Center for Vision RestorationUniversity of Pittsburgh School of Medicine Department of Neurobiology Center of NeuroscienceUniversity of Pittsburgh School of Medicine

Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.

关键词： cell clumps cell suspension cell transplantation differentiation direct-induced protocol glaucoma optic neuropathy regenerative medicine retinal ganglion cell retinal organoids stem cells

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Catalyst design and structure control for photocatalytic refineries of cellulosic biomass to fuels and chemicals

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Journal of Energy Chemistry 2024年第7期94卷 102-127页

作者： Lulu Sun Nengchao luo State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Lignocellulosic biomass is the largest renewable hydrocarbon resource on earth.Converting cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation fuels.State-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic biorefineries.Well-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of biorefineries.Besides,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation costs.Charge separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous chemicals.To account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product selectivity.In addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.

关键词： Photocatalysts Biorefineries Cellulose Fuels Hydrogen

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