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Spatiotemporal evolution of wildfire activity during the PaleoceneEocene Thermal Maximum in China

Science China Earth Sciences 2025年

作者： xueting wang Zuoling CHEN Linlin CUI xu wang State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences College of Earth and Planetary Sciences Institute of Geology and Geophysics Chinese Academy of Sciences

The Paleocene-Eocene Thermal Maximum（PETM） was the most prominent warming event in the Cenozoic and serves as a geological analog for the current global warming driven by anthropogenic CO2emissions from burning fossil *** a primary disruptor of Earth's ecosystems, wildfire activity affects the balance of ecosystems, the global carbon cycle, and climate change. Therefore, studying the evolution and driving mechanisms of wildfires during the PETM is essential for predicting wildfire activity under global warming scenarios and for understanding the carbon cycle in the context of wildfire disturbances. Current research on wildfires during the PETM has mainly focused on the Northern Hemisphere, particularly Europe and North America, whereas studies on Chinese mainland remain limited. In this study, we analyzed black carbon（BC）concentration and carbon isotope(δ13C) in the Beigou section of the nanyang Basin and the Xilutian section of the Fushun Basin to reconstruct the spatiotemporal evolution of wildfires in arid/semi-arid and humid zones. We integrated these findings with those of previous studies on the paleoclimate of the research area to elucidate the driving mechanisms behind wildfire occurrences. Our results indicate that wildfire activity weakened at the onset of the PETM, with the negative carbon isotope period characterized by low wildfire activity, except for a brief resurgence in the nanyang Basin. During the recovery phase of the PETM, wildfire activity gradually increased, returning to the pre-PETM levels. The prolonged low wildfire state was likely caused by extremely high temperatures and precipitation as well as the resulting vegetation succession. During the PETM recovery phase, increased wildfire activity transformed “short-term carbon sinks” of the biological-atmospheric carbon cycle into “long-term carbon sinks” through the burial of BC. This process of carbon sink conversion may have acted as a negative feedback mechanism, contributing to carbo

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Tunable non-Markovian and quantum coherence in the single-qubit dephasing noise channel

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： na-na Zhang Chao-Yi Wu xu Zhou Qi-Yuan Liu Cheng-Ge Liu Yong-Rui Guo Ren-Pu Li School of Optoelectronic Engineering Chongqing University of Posts and Telecommunications Department of Physics Applied Optics Beijing Area Major Laboratory Beijing Normal University

In this paper, we construct a single-qubit dephasing noise channel based on the nuclear magnetic resonance（NMR） system by employing the bath-engineering technology, and achieve the construction of the tunable non-Markovian environment in the dephasing noise channel. Our findings indicate that for the single-qubit system, the transition of system dynamics from Markovian to non-Markovian can be achieved by adjusting the base frequency of the noise power spectrum. However, the base frequency corresponding to this phase transition point is not fixed, and there is a certain relationship between it and the total evolution time of the single-qubit system. Through our research, we discovered a fundamental relationship: if the single-qubit system dynamics undergoe a transition from Markovian to non-Markovian at ω0within 0-2t ms, shortening the evolution time to 0-t ms results in an increase of the phase transition point to 2ω0. This insight offers crucial guidance for artificially crafting non-Markovian environments across arbitrary time scales in single-qubit systems, and it is not limited by the type of noise. Apart from system dynamics, quantum coherence is also a focal point of our research. We find that when the system dynamics exhibit non-Markovian behavior, the quantum coherence of the single-qubit system experiences revivals. Notably, the timing of these coherence revivals aligns with the instants of the non-Markovianity enhancement. Therefore, our research also serves as a pivotal foundation for the artificial manipulation and realization of quantum coherence revivals within diverse single-qubit systems.

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Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第1期68卷 329-336页

作者： Yuzhu Li Yumeng Gao Feng Tian Yu wang Yuan Yao Shaoliang Lin Xiang Ma Binbin xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

关键词： self-assembly conformation ordering alternating copolymer phosphorescence emission

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碱金属修饰g-C_3N_4的能带结构调控与载流子迁移过程

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物理化学学报 2016年第10期32卷 2488-2494页

作者：祝林马新国刘娜徐国旺黄楚云湖北工业大学理学院武汉430068 湖北工业大学太阳能高效湖北省协同创新中心武汉430068

采用平面波超软赝势方法研究了Li、na、K三种碱金属离子修饰对g-C_3N_4能带结构和载流子迁移过程的影响。对建立的六种吸附构型分别采用广义梯度近似和局域密度近似进行计算,发现三种碱金属离子均更趋向于吸附在g-C_3N_4片层内的大空洞... 详细信息

采用平面波超软赝势方法研究了Li、na、K三种碱金属离子修饰对g-C_3N_4能带结构和载流子迁移过程的影响。对建立的六种吸附构型分别采用广义梯度近似和局域密度近似进行计算,发现三种碱金属离子均更趋向于吸附在g-C_3N_4片层内的大空洞中央位置(F位置)。对于碱金属与g-C_3N_4形成的n型Schottky结,通过能带结构和功函数的计算,发现界面电荷的平衡使g-C_3N_4的能带电位分别整体下移1.52V(Li)、1.07V(na)、0.86V(K)。其中K离子的引入一方面将g-C_3N_4的价带和导带调整到更合适的氧化还原电位,另一方面增大了g-C_3N_4的最高占据轨道(HOMO)和最低未占据轨道(LOMO)的分布,有利于提高载流子的迁移率,同时出现的HOMO和LOMO轨道非共面特性有利于电子和空穴的分离。

关键词：光催化 g-C3N4 能带结构载流子迁移

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Enantioselective β-alkenylation of α,β-unsaturated aldehydes via chiral biphosphine ligand modified dirhodium(II) catalysis

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Science China Chemistry 2025年

作者： Guangli xu Hongda Chen Xiaoming wang State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences School of Chemistry and Materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Dirhodium(II) complexes have achieved great success in organic synthesis,and fine-tuning their catalytic properties with various bridging ligands is well-investigated in carbene ***,combining dirhodium(II) with a sophisticated ligand as a catalyst in other reactions is still extremely challenging,especially for the asymmetric synthesis of valuable chiral ***,we report a dirhodium(II)/(S)-MeO-BIPHEP catalytic system for the challenging asymmetric β-alkenylation of α,β-unsaturated aldehydes,affording the corresponding chiral conjugate addition products in good yields with high enantioselectivities.A couple of drug-derived substrates were also compatible with the protocol,which has been successfully used to prepare biologically relevant pyranochromene *** mechanistic studies suggested that the dirhodium core might remain intact over the catalytic cycle,and the chiral diphosphine ligand plays a key role in this novel reactivity and determining the high enantioselectivities of the asymmetric conjugate addition.

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Copper homeostasis and neurodegenerative diseases

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Neural Regeneration Research 2025年第11期20卷 3124-3143页

作者： Yuanyuan wang Daidi Li Kaifei xu Guoqing wang Feng Zhang International Research Laboratory of Ethnomedicine of Ministry of Education Key Laboratory of Basic Pharmacology of Ministry of EducationLaboratory Animal Center and Key Laboratory of Basic Pharmacology of Guizhou ProvinceZunyi Medical UniversityZunyiGuizhou ProvinceChina

Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of *** homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7B),and the three copper chaperones ATOX1,CCS,and *** in copper homeostasis can lead to either the deficiency or accumulation of copper in brain *** evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative ***,the exact mechanisms underlying these processes are not *** is a potent oxidant that increases reactive oxygen species production and promotes oxidative *** reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial *** oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory ***,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell *** study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease *** synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of heredit

关键词： Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease Wilson's disease

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Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： Hang Yang Yulei Xia Yue Ma Mingtong Gao Shuai Hou Shanshan xu Yanqiang wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

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Perfluoropentane-based oxygen-loaded nanodroplets reduce microglial activation through metabolic reprogramming

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Neural Regeneration Research 2025年第4期20卷 1178-1191页

作者： Wanxian Luo Chuanhui xu Linxi Li Yunxiang Ji Yezhong wang Yingjia Li Yongyi Ye Department of Medicine Ultrasonics Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Neuroscience Department of NeurosurgeryThe Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina

Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s *** perfluorocarbon droplets have been reported to not only possess a high oxygen-carrying capacity,but also exhibit remarkable anti-inflammatory ***,the role of perfluoropentane in microglia-mediated central inflammatory reactions remains poorly *** this study,we developed perfluoropentane-based oxygen-loaded nanodroplets(PFP-OLNDs)and found that pretreatment with these droplets suppressed the lipopolysaccharide-induced activation of M1-type microglia in vitro and in vivo,and suppressed microglial activation in a mouse model of Parkinson’s *** suppression led to a reduction in the inflammatory response,oxidative stress,and cell migration capacity in ***,the neurotoxic effects were mitigated,which alleviated neuronal ***,ultrahigh-performance liquid chromatography–tandem mass spectrometry showed that the anti-inflammatory effects of PFP-OLNDs mainly resulted from the modulation of microglial metabolic *** further showed that PFP-OLNDs regulated microglial metabolic reprogramming through the AKT-mTOR-HIF-1α***,our findings suggest that the novel PFP-OLNDs constructed in this study alleviate microglia-mediated central inflammatory reactions through metabolic reprogramming.

关键词： metabolic reprogramming microglia microglial migration nanotherapy neurodegenerative diseases neuroinflammation oxygen-loaded nanodroplets Parkinson’s disease perfluoropentane ultra-performance liquid chromatography–mass spectrometry

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Direct and rapid detection of serum amino acid and monoamine neurotransmitters to assist the diagnosis of panic disorder

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Science China Chemistry 2025年第1期68卷 377-384页

作者： Shiwen Liu xuerui Wan Meng Zhao Jiaqi wang Weilan Wu Linlin You Yonggui Yuan Qian xu Rong Gao Key Laboratory of Environmental Medicine Engineering Ministry of Education School of Public Health Southeast University Key Laboratory of Modern Toxicology of Ministry of Education Department of Hygienic Analysis and Detection School of Public HealthNanjing Medical University Department of Psychosomatics and Psychiatry Zhongda Hospital School of Medicine Southeast University

The measurement of amino acid and monoamine neurotransmitters（NTs） in serum plays a central role in the identification and monitoring of clinical panic disorder（PD）. However, the strong polarity and chemical heterogeneity of NTs make direct extraction and rapid detection extremely challenging. Herein, we developed a strategy that integrated solid phase extraction based on magnetic Fe3O4coated with polydopamine（Fe3O4@PDA） and direct analysis of mass spectrometry in real time（DART-MS） for quantification of 10 NTs. We systematically investigated the optimal conditions of this strategy to achieve good accuracy and precision. Compared with existing magnetic solid phase extraction methods for NTs detection in biological samples, this strategy could adsorb more targets while having similar adsorption efficiencies, and the total process time was reduced by an average of 69.42%. We rapidly determined the metabolic abnormality of 6 types of NTs in the serum of PD patients and demonstrated their diagnostic accuracy. In addition, an outstanding feature of PD in which tryptophan was more metabolized by the KYN pathway and the 5-hydroxytryptamine pathway was inhibited could be elucidated by this strategy. Our results highlighted the potential ability of Fe3O4@PDA coupled with DART-MS to assist in the clinical diagnosis of PD.

关键词： neurotransmitters panic disorder magnetic solid phase extraction direct analysis of mass spectrometry in real time

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基于粒子群优化算法的农业机器人控制策略研究

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农机化研究 2025年第1期47卷 205-209页

作者：王娜吴延凯许娜河南工业职业技术学院河南南阳473000

介绍了粒子群优化算法的概念,并由数学模型、边界约束和环境约束对农业机器人优化约束模型进行了分析,实现了对农业机器人的动态避障和路径规划。仿真实验表明:针对复杂的作业环境,农业机器人可以进行最优避障路径规划,且算法收敛速度较... 详细信息

介绍了粒子群优化算法的概念,并由数学模型、边界约束和环境约束对农业机器人优化约束模型进行了分析,实现了对农业机器人的动态避障和路径规划。仿真实验表明:针对复杂的作业环境,农业机器人可以进行最优避障路径规划,且算法收敛速度较快,能够满足设计要求,证明系统具有一定的可行性。

关键词：农业机器人粒子群优化约束模型避障路径规划

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