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Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： Xin li Yibo zhou Tao ZHAO Xingjian HE Yanhong PAN State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material CyclingCentre for Research and Education on Biological Evolution and Environment and Frontiers ScienceSchool of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Institute of Palaeontology Yunnan Key Laboratory of Earth System ScienceYunnan Key Laboratory for PalaeobiologyYunnan UniversityKunming650500China

Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the ***,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep *** address this,we conducted taphonomic experiments to simulate the transformation process of black *** changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman *** results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently *** Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature *** the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

Sequence-activated chemiluminescence probes:programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang Juan li wei-Hong Zhu Zhiqian Guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular EngineeringInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science&TechnologyShanghai 200237China

Sequence-activated chemiluminescence(CL)technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial *** fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest,thus enabling high-contrast signals under complex physiological *** sequential activation could be triggered by enzymes,reactive oxygen species(ROS),biothiols or changes in the *** unique sequence-activated CL probes bestow several advantages,including minimal background,deep-tissue penetration,and the ability of non-invasive or minimally invasive *** sequence-activated CL techniques represent a significant advancement in molecular imaging and *** this mini-review,we focus on the latest developments in sequential CL probes,addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

Identification of potential metabolites responsible for cold tolerance in buds of Vitis amurensis

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Horticultural Plant Journal 2025年第1期11卷 175-188页

作者： Qingyun li Huimin zhou Fengmei Chai Zemin Wang linchuan Fang wei Duan Peige Fan Zhenchang liang Shaohua li Qingfeng Wang Haiping Xin Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhanHubei 430074China Center of Economic Botany Core Botanical GardensChinese Academy of SciencesWuhanHubei 430074China Beijing Key Laboratory of Grape Sciences and Enology CAS Key Laboratory of Plant ResourcesInstitute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China Wuhan Academy of Agricultural Sciences WuhanHubei 430074China

Cold tolerance is one of the important traits for grapevine,especially in regions with extremely low temperatures in *** amurensis is wild species in the Vitis genus with excellent cold hardiness compared with Vitis ***,metabolites that contribute to the cold tolerance of *** remain ***,the metabolomics of buds from ***‘Zuoshan-1'during cold acclimation(CA)were identified,and cold-sensitive cultivar(***‘Jingzaojing')was used as the *** buds were collected in October,November,and December in 2016 and *** cold hardiness of the buds increased during CA in the two ***,browning was observed only in *** buds at temperature below-10℃.Among detected metabolites from buds,443 metabolites were overlapped between two ***-four and thirty differentially accumulated metabolites(DAMs)were identified in *** and ***,*** DAMs including monoacylglycerol(MAG,18:2)isomer 1,trehalose 6-phosphate,and D-glucose showed identical variations in the two grapevines,indicating conserved CA responses within the Vitis *** DAMs exhibited higher accumulation in *** than in ***,D-glucoronic acid,L-aspartic acid,azelaic acid,and 4-hydroxybenzoic acid were reported to accumulate during CA in other *** cold tolerance was detected in grapevine leaves with exogenous 5 mmol L^(-1)L-aspartic acid and 1%*** contributions of other DAMs found in *** such as Cyanidin 3-O-glucoside need to be further ***,eighteen metabolites accumulated in *** can be used for practical application in improvement of cold resistance in *** findings provide new insights into understanding the cold hardiness of ***.

关键词： Grapevine Metabolomics Bud Low temperature Cold hardiness

Arsenic exposure and oxidative damage to lipid,DNA,and protein among general Chinese adults:A repeated-measures cross-sectional and longitudinal study

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Journal of Environmental Sciences 2025年第1期147卷 382-391页

作者： Yongfang Zhang Min zhou Dongming Wang Ruyi liang wei liu Bin Wang weihong Chen Department of Occupational and Environmental Health School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Key Laboratory of Environment and Health Ministry of Education and Ministry of Environmental Protectionand State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Arsenic-related oxidative stress and resultant diseases have attracted global concern,while longitudinal studies are *** assess the relationship between arsenic exposure and systemic oxidative damage,we performed two repeatedmeasures among 5236 observations(4067 participants)in theWuhan-Zhuhai cohort at the baseline and follow-up after 3 *** total arsenic,biomarkers of DNA oxidative damage(8-hydroxy-2-deoxyguanosine(8-OHdG)),lipid peroxidation(8-isoprostaglandin F2alpha(8-isoPGF2α)),and protein oxidative damage(protein carbonyls(PCO))were detected for all *** we used linearmixed models to estimate the cross-sectional and longitudinal associations between arsenic exposure and oxidative ***-response curves were constructed by utilizing the generalized additive mixed models with thin plate *** adjusting for potential confounders,arsenic level was significantly and positively related to the levels of global oxidative damage and their annual increased rates in dose-response *** cross-sectional analyses,each 1%increase in arsenic levelwas associated with a 0.406%(95%confidence interval(CI):0.379%to 0.433%),0.360%(0.301%to 0.420%),and 0.079%(0.055%to 0.103%)increase in 8-isoPGF2α,8-OHdG,and PCO,*** importantly,arsenic was further found to be associated with increased annual change rates of 8-isoPGF2α(β:0.147;95%CI:0.130 to 0.164),8-OHdG(0.155;0.118 to 0.192),and PCO(0.050;0.035 to 0.064)in the longitudinal *** study suggested that arsenic exposurewas not only positively related with global oxidative damage to lipid,DNA,and protein in cross-sectional analyses,but also associated with annual increased rates of these biomarkers in dose-dependent manners.

关键词： Arsenic Oxidative stress Oxidative damage 8-isoPGF2α 8-OHdG Protein carbonyls(PCO)

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen CHEN wei CAO Bingwei liU Xinhui li Hang College of Mechanical and Aerospace Engineering Jilin UniversityChangchun 130025China School of Mechanical and Vehicle Engineering Changchun UniversityChangchun 130022China

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator(FPSEG)as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m^(3)/h and 6.5 m^(3)/h(~45.1%)air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m^(3)/h air intake.

关键词： biomass gasification combined heat and power(CHP) porous media combustion power generation

Aerodynamic Optimization and Flow Mechanism for a Compressor Cascade at Low Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 92-109页

作者： li lin ZHANG Jianshe CHEN Caiyan TAN wei ZHANG Yanfeng Key Laboratory of light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Key Laboratory of Science and Technology on Advanced light-duty Gas-turbine Beijing 100190China

Low-Reynolds-number effect is an important factor affecting the performance of compressors and other main components of high-altitude long-endurance unmanned aerial *** improve the flow condition and reduce flow loss under the condition of high altitude and low Reynolds number(Re),this paper proposes an optimization process based on a surrogate model,which combines the class-shape transformation method(CST),the Latin hypercube sampling(LHS)method,the light gradient-boosting machine algorithm(lightGBM),and a genetic algorithm(GA)to optimize a high-subsonic compressor *** surrogate model is verified to be accurate and can be used in the optimization *** accuracy of the GA is higher than the other algorithms under common test *** optimization results are verified by numerical simulation,and the flow differences before and after optimization are compared,especially the flow within the boundary *** changing the blade shape,the optimization process adjusts the loading distribution to delay the transition of the optimized blade on the suction surface,which changes the turbulent reattachment in the laminar separation bubble(LSB)into laminar ***,the mixing loss induced by the turbulent reattachment of the LSB and the wake loss of turbulent separation at the trailing edge are significantly reduced,and the performance of the compressor profile is finally *** addition,turbulent separation of the optimized profile is delayed reducing the range of the wake region on the suction *** this optimization process,the reduction of total pressure loss coefficient at Re of 2.5×10^(5),3.5×10^(5),and 4.5×10^(5) are 16.32%,20.76%,and 22.16%,respectively.

关键词： low Reynolds numbers compressor optimization boundary layer transition

Research on Stock Price Prediction Method Based on the GAN-LSTM-Attention Model

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Computers, Materials & Continua 2025年第1期82卷 609-625页

作者： Peng li Yanrui wei lili Yin College of Computer Science and Technology Harbin University of Science and TechnologyHarbin150006China

Stock price prediction is a typical complex time series prediction problem characterized by dynamics,nonlinearity,and *** paper introduces a generative adversarial network model that incorporates an attention mechanism(GAN-LSTM-Attention)to improve the accuracy of stock price ***,the generator of this model combines the Long and Short-Term Memory Network(LSTM),the Attention Mechanism and,the Fully-Connected Layer,focusing on generating the predicted stock *** discriminator combines the Convolutional Neural Network(CNN)and the Fully-Connected Layer to discriminate between real stock prices and generated stock ***,to evaluate the practical application ability and generalization ability of the GAN-LSTM-Attention model,four representative stocks in the United States of America(USA)stock market,namely,Standard&Poor’s 500 Index stock,Apple Incorporatedstock,AdvancedMicroDevices Incorporatedstock,and Google Incorporated stock were selected for prediction experiments,and the prediction performance was comprehensively evaluated by using the three evaluation metrics,namely,mean absolute error(MAE),root mean square error(RMSE),and coefficient of determination(R2).Finally,the specific effects of the attention mechanism,convolutional layer,and fully-connected layer on the prediction performance of the model are systematically analyzed through ablation *** results of experiment show that the GAN-LSTM-Attention model exhibits excellent performance and robustness in stock price prediction.

关键词： Stock price prediction generative adversarial network attention mechanism time-series prediction

Spin freezing induced giant exchange bias in a doped Hund's metal

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 167-174页

作者： Shunjiao li Dan Zhao Jian li Baolei Kang Min Shan Yanbing zhou Xuyang li Tao Wu Xianhui Chen Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Superconducting Electronics(CENSE) Shanghai 200050China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Exchange bias(EB)is a fundamental phenomenon in widespread information ***,a comprehensive understanding of its microscopic origin remains a great *** key issue in the debate is the role of frustration and disorder in the EB mechanism,which motivates the exploration of the EB effect in spin glass(SG)***,in the SG state of Crdoped Hund's metal CsFe_(2)As_(2),we discover a giant EB effect with a maximum bias field of -2 T,which is almost two orders of magnitude larger than that of traditional alloy *** results indicate that the giant EB effect should originate from the exchange interactions at the natural boundaries between the tunable ferromagnetic-like(FM)regions around Cr dopants and the SG matrix,via which the FM spins are strongly pinned by the frozen spins in the SG *** addition,the temperaturedependent and cooling-field-dependent EB behaviors could be interpreted well by the SG model with frustrated FM/SG boundaries,which provides an intuitive and explicit understanding of the impact of glassy parameters on the EB *** these results suggest that the correlated metals are promising directions for exploring the EB effect in the SG state.

关键词： Hund's metal spin glass exchange bias iron-based superconductor

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Study on cook-off characteristics and thermal safety venting area of RBOE charge

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Defence Technology(防务技术) 2025年第1期43卷 271-287页

作者： Kebin Zhang Wenbin li Changfang Zhao Zhifang wei Shuxia Zhang Jin li School of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030000China ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing 210094China Department of Engineering Mechanics CNMM and AMLTsinghua UniversityBeijing 100084China

RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the *** on the thermal decomposition reaction characteristics and combustion characteristics of each component of RBOE explosive,the cook-off calculation models of RBOE warhead before and after ignition were *** addition,closed and vented warheads were designed,as well as fast and slow cook-off test *** cook-off characteristics and thermal safety venting area of RBOE warhead were extensively *** results showed that the closed RBOE warhead underwent deflagration reaction under both slow and fast cook-off *** calculation result of the shell wall temperature before slow cookoff ignition response of the warhead was 454.06 K,with an error of+1.75%compared to the test result of462.15 K,and the temperature rise rate calculated was in good agreement with the *** calculated ignition time of RBOE warhead under fast cook-off was 161 s,with an error of+8.8%compared to the test result of 148 s,which verified the accuracy of cook-off model of RBOE warhead before *** to the cook-off calculation model of the warhead after ignition and cook-off test of the vented warhead,it was determined that the thermal safety venting area was 1124.61 mm^(2)for fast cook-off and 530.66 mm~2 for slow cook-off,effectively preventing the reaction of warhead above ***,this study provides a scientific basis for the thermal safety design and evaluation of insensitive warheads.

关键词： RBOE explosive Cook-off model Temperature distribution Pressure growth Venting area