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Chinese Journal of Chemistry 2024年第11期42卷 1247-1259页

作者： Wei-Jiao Feng Yue Gu Pei-Zhi Huang Hong-Ying Yang Rui Zhang Yi-Lin He Ting-Hong Lv Ya Li Kun Gao State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhouGansu730000 China Research Institute Lanzhou Jiaotong UniversityLanzhouGansu730070 China

Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus *** 1 possesses an unprecedented 3/5/7/5/5/6/5/3 fused octacyclic scaffold,featuring a 6(5→4)-abeo-lindenane monomer,while 2 exhibits a 3/5/6/6/5/6/5/3 fused octacyclic *** structures were determined through a combination of spectroscopic analyses and X-ray *** 1,2,and 18 demonstrated significant inhibitory effects on lipid accumulation and effectively reduced the levels of triglycerides and total cholesterol,as well as the levels of aspartate aminotransferase and alanine aminotransferase in a HepG2 cell *** addition,compounds 1,2,and 18 significantly suppressed the protein expression of the fatty acid synthase(FASN)and the sterol regulatory element-binding protein 1(SREBP1).Moreover,the anti-inflammatory assay showed that compounds 19—22 and 25 inhibited the NO production induced by lipopolysaccharide in RAW 264.7 macrophages with IC50 values of 7.89±0.44,6.25±0.46,2.98±0.29,10.77±0.60,and 3.60±0.28μmol/L.

关键词： Chloranthus japonicus Lindenane-type sesquiterpenoid dimers Lipid-lowering activity Anti-inflammatory activity NMR spectroscopy Natural products X-ray diffraction

Phylotranscriptomic discordance is best explained by incomplete lineage sorting within Allium subgenus Cyathophora and thus hemiplasy accounts for interspecific trait transition

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Plant Diversity 2024年第1期46卷 28-38页

作者： Zengzhu Zhang Gang Liu Minjie Li State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000GansuPR China

The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and *** can be learned about this process from phylogeny-based trait ***,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear ***,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium *** concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS ***,GTD was high across the genomes of ***:~27%e38.9%of the SCG trees were in conflict with the species *** and nuclear incongruence was also *** coalescent simulations indicated that such GTD was mainly a product of *** hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the *** phylogeny may have caused the character transition,as well as the anomalous cpDNA *** study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.

关键词： Hemiplasy Multispecies coalescence Lineage sorting Gene tree discordance Phylotranscriptomics Allium subg.Cyathophora

Depressive semantic awareness from vlog facial and vocal streams via spatio-temporal transformer

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Digital Communications and Networks 2024年第3期10卷 577-585页

作者： Yongfeng Tao Minqiang Yang Yushan Wu Kevin Lee Adrienne Kline Bin Hu School of Information Science and Engineering Lanzhou UniversityLanzhouChina The School of Accounting Auditing and TaxationBusiness SchoolUNSW SydneyAustralia Department of Preventive Medicine Northwestern UniversityChicagoILUnited States

With the rapid growth of information transmission via the Internet,efforts have been made to reduce network load to promote *** such application is semantic computing,which can extract and process semantic *** media has enabled users to share their current emotions,opinions,and life events through their mobile ***,people suffering from mental health problems are more willing to share their feelings on social ***,it is necessary to extract semantic information from social media(vlog data)to identify abnormal emotional states to facilitate early identification and *** studies do not consider spatio-temporal information when fusing multimodal information to identify abnormal emotional states such as *** solve this problem,this paper proposes a spatio-temporal squeeze transformer method for the extraction of semantic features of ***,a module with spatio-temporal data is embedded into the transformer encoder,which is utilized to obtain a representation of spatio-temporal ***,a classifier with a voting mechanism is designed to encourage the model to classify depression and non-depression *** are conducted on the D-Vlog *** results show that the method is effective,and the accuracy rate can reach 70.70%.This work provides scaffolding for future work in the detection of affect recognition in semantic communication based on social media vlog data.

关键词： Emotional computing Semantic awareness Depression recognition Vlog data

Applicability of different indices for delineating the boundary of arid region: A case study in northwestern China

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Journal of Earth Science 2024年

作者： Xue Peng Xiang Li Yingyibing Shen Xuehua Che Shipei Dong Zhuolun Li Key Laboratory of Western China's Environmental Systems (Ministry of Education) College of Earth and Environmental Sciences center for Glacier and Desert Research lanzhou university

Arid regions are vital components of Earth's land surface. Clarifying the area/boundary of arid region is crucial for comprehending area changes and potential mechanisms. However， the accuracy and applicability of arid region boundary delineated by different indices remain unclear. In this study， the annual precipitation （AP）， humidity index （H）， and aridity index （K） were calculated for delineating arid region of China using 106 meteorological stations during 1990–2019. The results suggest that AP and H can accurately delineate arid region， because they are consistent with the distribution of typical soil and vegetation in arid region， whereas K is not. Moreover， AP is the best index for delineating arid region in regions with limited meteorological data， especially in studying long-term patterns and mechanisms of area changes. The accuracy of delineating arid region using H is enhanced in regions with abundant meteorological data. Over the past 30 years， influenced by the increase of atmospheric moisture influx and precipitation， the area in arid region of northwestern China decreased by 70×103–90×103km2， resulting in the present area of approximately 1.55×106km2. This study provides appropriate indices for delineating arid region， contributing to improving our knowledge of regional responses difference to climate change.

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Recent progress in flexible Zn-ion hybrid supercapacitors: Fundamentals, fabrication designs, and applications

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Carbon Energy 2023年第1期5卷 82-122页

作者： Muhammad Sufyan Javed Sumreen Asim Tayyaba Najam Muhammad Khalid Iftikhar Hussain Awais Ahmad Mohammed A.Assiri Weihua Han School of Physical Science and Technology Lanzhou UniversityLanzhouGansuChina Institute of Chemistry Khwaja Fareed University of Engineering and Information TechnologyPunjabPakistan College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhenGuangdongChina Department of Mechanical Engineering City University of Hong KongKowloonHong KongChina Departamento de Quimica Organica Universidad de CordobaCordobaSpain Department of Chemistry Faculty of ScienceKing Khalid UniversityAbhaSaudi Arabia

One of the most exciting new developments in energy storage technology is flexible Zn-ion hybrid supercapacitors(f-ZIHSCs),which combine the high energy of Zn-ion batteries with high-power supercapacitors to satisfy the needs of portable flexible ***,the development of f-ZHSCs is still in its infancy,and there are numerous barriers to overcome before they can be widely implemented for practical *** review gives an up-to-date description of recent achievements and underlying concepts in energy storage mechanisms of f-ZIHSCs and emphasizes the critical role of cathode,anode,and electrolyte materials systems in speeding the prosperity of *** innovative nanostructured-based cathode materials for f-ZIHSCs include carbon(e.g.,porous carbon,heteroatom-doped carbon,biomass-derived porous carbon,graphene,etc.),metal-oxides,MXenes,and metal/covalentorganic frameworks,and other materials(e.g.,activated carbon,phosphorene,etc.)are mainly ***,the latest developments in flexible anode and electrolyte frameworks and impacts of electrolyte compositions on the electrochemical properties of f-ZIHSC are ***,the advancements based on fabrication designs,including quasi-solid-state,micro,fiber-shaped,and all climate-changed f-ZIHSCs,are discussed in ***,a summary of current challenges and recommendations for the future progress of advanced f-ZIHSC are *** review article is anticipated to further understand the viable strategies and achievable approaches for assembling high-performance f-ZIHSCs and boost the technical revolutions on cathode,anode,and electrolytes for f-ZIHSC devices.

关键词： electrode electrolyte flexible MOFs MXenes Zn-ion hybrid supercapacitor

Seasonal to sub-seasonal variations of the Asian Tropopause Aerosols Layer affected by the deep convection,surface pollutants and precipitation

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Journal of Environmental Sciences 2022年第4期34卷 53-65页

作者： Dongyou Wu Tenglong Shi Xiaoying Niu Ziqi Chen Jiecan Cui Yang Chen Xueying Zhang Jun Liu Mingxia Ji Xin Wang Wei Pu College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Jilin Weather Modification Office Changchun 130000China School of Earth System Science Tianjin UniversityTianjin 300072China

The Asian Tropopause Aerosols Layer(ATAL)refers to an accumulation of aerosols in the upper troposphere and lower stratosphere during boreal summer over Asia,which has a fundamental impact on the monsoon system and climate *** this study,we primarily analyze the seasonal to sub-seasonal variations of the ATAL and the factors potentially influencing those variations based on MERRA2 *** ability of the reanalysis to reproduce the ATAL is well validated by CALIPSO observations from May to October *** results reveal that the ATAL has a synchronous spatiotemporal pattern with the development and movement of the Asian Summer *** enhancement of ATAL intensity is found during the prevailing monsoon period of July-August,with two maxima centered over South Asia and the Arabian *** to the fluctuations of deep convection,the ATAL shows an episodic variation on a timescale of 7-12 *** analysis indicates that deep convection dominates the variability of the ATAL with a contribution of 62.7%,followed by a contribution of 36.6%from surface *** impact of precipitation is *** ATAL further shows a clear diurnal variation:the peak of ATAL intensity occurs from 17:30 to 23:30 local time(LT),when the deep convection becomes strongest;the minimum ATAL intensity occurs around 8:30 LT owing to the weakened deep convection and photochemical reactions in *** aerosol components of the ATAL show different spatiotemporal patterns and imply that black carbon and organic carbon come mainly from India,whereas sulfate comes mainly from China during the prevailing monsoon period.

关键词： ATAL Seasonal to sub-seasonal variations Deep convection Asian Summer Monsoon

The Variability of Air-sea O_(2)Flux in CMIP6:Implications for Estimating Terrestrial and Oceanic Carbon Sinks

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Advances in Atmospheric Sciences 2022年第8期39卷 1271-1284,I0024-I0026页

作者： Changyu LI Jianping HUANG Lei DING Yu REN Linli AN Xiaoyue LIU Jiping HUANG College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Collaborative Innovation center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Enlightening Bioscience Research center MississaugaL4X 2X7Canada

The measurement of atmospheric O_(2)concentrations and related oxygen budget have been used to estimate terrestrial and oceanic carbon ***,a discrepancy remains in assessments of O_(2)exchange between ocean and atmosphere(***-sea O_(2)flux),which is one of the major contributors to uncertainties in the O_(2)-based estimations of the carbon ***,we explore the variability of air-sea O_(2)flux with the use of outputs from Coupled Model Intercomparison Project phase 6(CMIP6).The simulated air-sea O_(2)flux exhibits an obvious warming-induced upward trend(~1.49 Tmol yr−2)since the mid-1980s,accompanied by a strong decadal variability dominated by oceanic climate *** subsequently revise the O_(2)-based carbon uptakes in response to this changing air-sea O_(2)*** results show that,for the 1990−2000 period,the averaged net ocean and land sinks are 2.10±0.43 and 1.14±0.52 GtC yr−1 respectively,overall consistent with estimates derived by the Global Carbon Project(GCP).An enhanced carbon uptake is found in both land and ocean after year 2000,reflecting the modification of carbon cycle under human *** derived from CMIP5 simulations also investigated in the study allow for comparisons from which we can see the vital importance of oxygen dataset on carbon uptake estimations.

关键词： air-sea O_(2)flux carbon budget land and ocean carbon sinks CMIP6

Tuning Intermolecular Singlet Fission Efficiencies of Perylenediimide Derivatives through Bay Aromatic Substitution

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Chinese Journal of Chemistry 2023年第10期41卷 1170-1176页

作者： Chun-Lin Sun Xiao-Zhen Wang Hu-Hu Tian Qi-Wei Song Bo-Yang Zhang Xian Fei Cheng Zhang Jian-Rong Ma Juan Ye Hao-Li Zhang State Key Laboratory of Applied Organic Chemistry Key Laboratory of Special Function Materials and Structure DesignCollege of Chemistry and Chemical EngineeringFrontiers Science Center for Rare IsotopesLanzhou UniversityLanzhouGansu 730000China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistryTianjin UniversityCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China

Singlet fission(SF)has potential applications in high-efficiency photo-energy harvesting applications,but its practical application is hindered by the limited number of *** this work,we explored the bay aromatic substitution strategy for the design of new perylenediimide(PDI)based SF materials.A series of PDI derivatives with biphenyl or naphthalene units substituted at the bay posi-tions were designed and synthesized to investigate the effects of aromatic substitutes on their photodynamic *** bay substitutions do not shift the energy level of the PDI core significantly but give rise to different intermolecular coupling strengths in the thin films and affect the intermolecular SF *** transient absorption(fsTA)spectroscopy reveals that appro-priate spacing configuration from the bay aromatic substitution groups enhances the SF yields by promoting the interaction of neighbouring PDI *** exciton yields of up to 183%have been obtained from these new PDI derivatives,making them po-tential candidates in future SF-based optoelectronics.

关键词： Singlet fission Perylenediimide Femtochemistry Thin films Density functional calculations

Two‑Dimensional Metal Halides for X‑Ray Detection Applications

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Nano-Micro Letters 2023年第8期15卷 405-422页

作者： Yumin Li Yutian Lei Haoxu Wang Zhiwen Jin School of Physical Science and Technology and lanzhou center for Theoretical Physics and Key Laboratory of Theoretical Physics of Gansu Province Lanzhou UniversityLanzhou 730000People’s Republic of China

Metal halide perovskites have recently emerged as promising candidates for the next generation of X-ray detectors due to their excellent optoelectronic ***,two-dimensional(2D)perovskites afford many distinct properties,including remarkable structural diversity,high generation energy,and balanced large exciton binding *** the advantages of 2D materials and perovskites,it successfully reduces the decomposition and phase transition of perovskite and effectively suppresses ion ***,the existence of a high hydrophobic spacer can block water molecules,thus making 2D perovskite obtain excellent *** of these advantages have attracted much attention in the field of X-ray *** review introduces the classification of 2D halide perovskites,summarizes the synthesis technology and performance characteristics of 2D perovskite X-ray direct detector,and briefly discusses the application of 2D perovskite in ***,this review also emphasizes the key challenges faced by 2D perovskite X-ray detectors in practical application and presents our views on its future development.

关键词： Two-dimensional perovskite High stability Ion migration Charge transport X-ray Detector

Engineering topological state transfer in four-period Su–Schrieffer–Heeger chain

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Chinese Physics B 2023年第2期32卷 87-91页

作者：包茜茜郭刚峰谭磊 lanzhou center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceLanzhou UniversityLanzhou 730000China Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China

An extended Su–Schrieffer–Heeger(SSH) model containing four periods of the hopping coefficients, called SSH4 model, is constructed to explore robust quantum state transfer. The gap state protected by the energy gap plays the role of the topological channel where the particle initially located at the last lattice site has the probability to arise at the first and all even lattice sites equally. Serving those sites as ports, a multi-port router can be realized naturally, and the fidelity reaches unity in a wide range of parameters under the long chain and random disorder. Further, when we reduce the third intracell hopping to a small value, the occupancy probability of the second lattice site in every unit cell will reduce to zero, by which a new topological router can be induced. In addition, our SSH4 model can work as a 1/3 beam splitter. Namely, the particle initially occupies the first lattice site and finally appears with equal probability at three lattice sites. We can also realize a 1/2 beam splitter. Our four-period SSH model provides a novel way for topological quantum information processing and can engineer two kinds of quantum optical devices.

关键词： topological state transfer robust high fidelity