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Wood use and forest management by Neolithic millet farmers at the Xinglong site,northern China

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Science China Earth Sciences 2024年第6期67卷 1910-1921页

作者： Hui SHEN Zhenwei qiu Keliang ZHAO Xinying ZHOU Xiaoqiang LI Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China National Museum of China Beijing 100006China University of Chinese Academy of Sciences Beijing 100049China

The origin and development of agriculture and its relationship with climate change are hotly debated topics among environmental *** this study,we analyzed wood charcoal materials from the Neolithic Xinglong site in northern China in order to understand the woody vegetation around the site and how early millet farmers shaped local *** results suggest that the area around the Xinglong sites during 8700-7000 yr BP was primarily woodlands,including Prunus sibirica shrubs,Ulmus and Acer forests,and Populus stands near *** 8000 to 7000 yr BP,the warm and humid climate probably contributed to the expansion of Acer,Rhamnus,and Juniperus,and may have facilitated the development of early millet *** these ancient wood fragments that we studied,the high percent of Prunus charcoal appears to indicate an abundance of fruit trees,which might have constituted the main component of local ***,the wood taxa illustrate the existence of a variety of ecological habitats,and it is logical to assume that people made full use of the locally available wood ***,Populus and Ulmus were the dominant sources of *** results of tree-ring curvature analyses indicate that people mainly collected trunks or large branches of Ulmus,Populus,Acer,and Juniperus *** interpret the increasing use of Prunus twigs and the declining percentage of Prunus charcoal in the period between 8000-7000 yr BP as indicating that people started to protect and manage wild fruit *** may have started pruning to acquire more food resources as part of the cultural responses and adaptation strategies employed by these early millet cultivators.

关键词： Xinglong site Wood charcoal Wood use Woodland management

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A new nonfullerene acceptor with an extended π conjugation core enables ternary organic solar cells approaching 19%efficiency

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Nano Research 2024年第5期17卷 4062-4068页

作者： Chunyan Liu Nailiang qiu Zhengjin Li Yan Lu School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China School of Chemistry Chemical Engineering and MaterialsJining UniversityQufu 273155China

In organic solar cells(OSCs),it is an effective way to improve the power conversion efficiency(PCE)by adding a guest component with appropriate absorption and energy levels in the host ***,a new nonfullerene acceptor(NFA)named TBF-2Cl was developed by the strategy of expanding theπconjugated core of 2,2’-(((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b’]dithiophene-2,7-diyl)bis(methaneylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IDT-4Cl)with two benzene *** increase of benzene units,TBF-2Cl exhibits higher lowest unoccupied molecular orbital(LUMO)level of-3.75 eV than that of one benzene unit based NFA IDT-4Cl and fluorene core based NFA F-2Cl,which facilitates enhancing the open-circuit voltage(V_(oc))of ternary ***,TBF-2Cl film shows a medium optical bandgap with the absorption range from 500-800 nm,being well complementary with the wide bandgap polymer donor D18 and narrow bandgap NFA ***,a remarkable PCE of 18.92%with a high short-circuit current density(J_(sc))of 27.40 mA·cm^(-2),a fill factor(FF)of 0.749,especially an outstanding V_(oc) of 0.922 V was achieved for the optimal ternary device based on D18:TBF-2Cl:CH-6F,surpassing the binary counterpart(17.08%).The findings provide insight into the development of new guest acceptors for obtaining more efficient OSCs.

关键词： medium optical bandgap high lowest unoccupied molecular orbital(LUMO)level the third component ternary organic solar cell high open-circuit voltage

Multilevel Attention Unet Segmentation Algorithmfor Lung Cancer Based on CT Images

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Computers, Materials & Continua 2024年第2期78卷 1569-1589页

作者： Huan Wang Shi qiu Benyue Zhang Lixuan Xiao Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’anChina School of Biomedical Engineering Fourth Military Medical UniversityXi’anChina University of Illinois at Urbana Champion ChampaignUSA

Lung cancer is a malady of the lungs that gravely jeopardizes human ***,early detection and treatment are paramount for the preservation of human *** computed tomography(CT)image sequences can explicitly delineate the pathological condition of the *** meet the imperative for accurate diagnosis by physicians,expeditious segmentation of the region harboring lung cancer is of utmost *** utilize computer-aided methods to emulate the diagnostic process in which physicians concentrate on lung cancer in a sequential manner,erect an interpretable model,and attain segmentation of lung *** specific advancements can be encapsulated as follows:1)Concentration on the lung parenchyma region:Based on 16-bit CT image capturing and the luminance characteristics of lung cancer,we proffer an intercept histogram algorithm.2)Focus on the specific locus of lung malignancy:Utilizing the spatial interrelation of lung cancer,we propose a memory-based Unet architecture and incorporate skip connections.3)Data Imbalance:In accordance with the prevalent situation of an overabundance of negative samples and a paucity of positive samples,we scrutinize the existing loss function and suggest a mixed loss *** results with pre-existing publicly available datasets and assembled datasets demonstrate that the segmentation efficacy,measured as Area Overlap Measure(AOM)is superior to 0.81,which markedly ameliorates in comparison with conventional algorithms,thereby facilitating physicians in diagnosis.

关键词： Lung cancer computed tomography computer-aided diagnosis Unet segmentation

An Advanced Image Processing Technique for Backscatter-Electron Data by Scanning Electron Microscopy for Microscale Rock Exploration

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Journal of Earth Science 2024年第1期35卷 301-305页

作者： Zhaoliang Hou Kunfeng qiu Tong Zhou Yiwei Cai Frontiers Science Center for Deep-time Digital Earth China University of GeosciencesBeijing 100083China Department of Geology University of ViennaVienna 1090Austria State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChinaUniversity of GeosciencesBeijing 100083China

Backscatter electron analysis from scanning electron microscopes(BSE-SEM)produces high-resolution image data of both rock samples and thin-sections,showing detailed structural and geochemical(mineralogical)*** allows an in-depth exploration of the rock microstructures and the coupled chemical characteristics in the BSE-SEM image to be made using image processing *** image processing is a powerful tool for revealing the more subtle data“hidden”in a picture,it is not a commonly employed method in geoscientific microstructural ***,we briefly introduce the general principles of image processing,and further discuss its application in studying rock microstructures using BSE-SEM image data.

关键词： Image processing rock microstructures electron-based imaging data mining

Two-stage Scheduling for Island CPHH IES Considering Plateau Climate

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1775-1786页

作者： Yuchen Pu Qi Li Yibin qiu Xueli Zou Weirong Chen School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China

In this paper,an island integrated energy system(IES)combining power,heat and hydrogen(CPHH)is built,and optimal power-heat-hydrogen scheduling is studied under actual plateau meteorological *** the comprehensive demands of residents,an IES including renewable energy sources(RESs),fuel cell,electrolyzer,electric boiler,thermal energy storage device and new energy vehicles is established and *** the first stage of operation,according to the prediction of RESs and demands,day-ahead optimization is carried out which aims to minimize operation cost,while electric vehicles(EVs)are considered as special demand response(DR)*** the second stage of operation,ultra-short-term prediction is implemented to provide prediction data for model predictive control(MPC),realizing real-time *** as a CPHH system,the fuel cell and electrolyzer collaborate to meet various needs of the plateau residential area with high *** addition,the method and IES structure proposed in this paper is compared with other options.

关键词： CPHH feul cell hydrogen island IES scheduling

Residue Based Open-Loop Modal Analysis Method for Detecting LFMR of PMSG-WFs Penetrated Power Systems

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1454-1465页

作者： Luonan qiu Tianhao Wen Yang Liu Q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou510640China

This paper proposes a residue based open-loop modal analysis method to detect low frequency modal resonance(LFMR),including asymmetric low frequency modal attraction(ALFMA)and asymmetric low frequency modal repulsion(ALFMR),of permanent magnetic synchronous generator based wind farms(PMSG-WFs)penetrated power *** formation of ALFMA and ALFMR caused by two open-loop low frequency oscillation(LFO)modes moving close and apart is analyzed in *** predicting the trajectories of closed-loop LFO modes based on calculation of residue of open-loop LFO modes,both ALFMA and ALFMR can be *** proposed method can select LFO modes which move to the right half complex plane as control parameters *** studies are carried out on a three-machine power system and a four-machine 11-bus power system to verify the properties of the proposed method.

关键词： Asymmetric low frequency modal attraction asymmetric low frequency modal repulsion low frequency modal resonance residue based open-loop modal analysis method

Effect of Tanshinone IIA on High Glucose-induced Apoptosis and Oxidative Stress Damage in Vascular Endothelial Cells

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Chinese Journal of Biomedical Engineering 2024年第2期33卷 62-68页

作者： qiu Shui-lin HUANG Rong HUANG Jian-qing qiu Rong-shui Longyan First Affiliated Hospital of Fujian Medical University Xiamen Medical College Affiliated Haicang Hospital

Objective: The primary cause of microvascular disease in diabetic complications is long-term hyperglycemia, wherein the damage and apoptosis of vascular endothelial cells play a significant role. Sodium tanshinone IIA sulfonate(STS) has been found to have beneficial effects on cardiovascular health. This study aimed to investigate the impact of STS on high glucose-induced apoptosis and oxidative stress damage in vascular endothelial cells, as well as its potential protective mechanisms. Methods:Human umbilical vein endothelial cells(HUVECs) were divided into five groups:low-glucose group, high-glucose group, and three STS groups(STS-a, STS-b, and STS-c). The low-glucose group was incubated with DMEM low-sugar medium containing 5.5 mmol·L-1glucose, while the high-glucose group was treated with 33.3mmol·L-1glucose. The STS groups were exposed to 10, 30, and 50 μg·m L-1of STS,respectively. Each group was cultured for 72 h, and the MTT method was utilized to assess cell proliferation. Additionally, flow cytometry was employed to monitor changes in cell apoptosis and cellular oxidative stress indicators at 24, 48, and 72 h of cell culture in each group. Results: As time went on, the cell proliferation ability and apoptosis rate of each group gradually increased. The high-glucose group exhibited lower proliferation ability compared to the other groups. The STS-c group demonstrated the highest OD value for proliferation ability(24 h: 1.19±0.12; 48 h: 1.20±0.13; 72 h:1.25 ±0.12), but it was still lower than that of the low-sugar group. Notably, the high-glucose group had the highest cell apoptosis rate, while the low-glucose group had the lowest. The apoptosis rate of the STS-c group(24 h: 8.02±0.13; 48 h: 10.10±0.12;72 h: 13.18 ±0.11)% was between that of the low-glucose group and the high-glucose group, and lower than the STS-a and STS-b groups. Furthermore, the high-glucose group exhibited the highest malondialdehyde and nitric oxide synthase activities, as well as super

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Extracorporeal membrane oxygenation as a bridging therapy for patients with thiamine deficiency-induced pulmonary arterial hypertension

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World Journal of Emergency Medicine 2024年第2期15卷 147-149页

作者： Fangfang qiu Weixing Dai Tengyue Huang Min Li Department of Intensive Care Unit the Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China Department of Intensive Care Unit the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China

Thiamine deficiency is characterized by a deficiency of thiamine(vitamin B1),lactic acidosis,pulmonary arterial hypertension(PAH),right-sided heart failure,and peripheral nerve *** deficiency is easily misdiagnosed and missed during clinical practice and is associated with death in severe cases.[1,2]Here we reported a patient who was admitted to the hospital with severe metabolic acidosis and pulmonary hypertension and finally diagnosed with thiamine deficiency by detecting plasma vitamin B1 *** clinically obvious thiamine deficiency is rare,and cases of thiamine deficiency requiring extracorporeal membrane oxygenation(ECMO)treatment are rarer,we believe that our case will be helpful for emergency clinicians.

关键词： vitamin hypertension arterial

Harnessing overlapped temperature-salinity gradient in solar-driven interfacial seawater evaporation for efficient steam and electricity generation

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Journal of Energy Chemistry 2024年第8期95卷 694-700,I0015页

作者： Peida Li Dongtong He Jingchang Sun Jieshan qiu Zhiyu Wang State Key Lab of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029LiaoningChina College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Solar-driven interfacial water evaporation(SIWE)offers a superb way to leverage concentrated solar heat to minimize energy dissipation during seawater *** also engenders overlapped temperaturesalinity gradient(TSG)between water-air interface and adjacent seawater,affording opportunities of harnessing ***,the efficiency of conventional SIWE technologies is limited by significant challenges,including salt passivation to hinder evaporation and difficulties in exploiting overlapped TSG ***,we report self-sustaining hybrid SIWE for not only sustainable seawater desalination but also efficient electricity generation from *** enables spontaneous circulation of salt flux upon seawater evaporation,inducing a self-cleaning evaporative interface without salt passivation for stable steam ***,this design enables spatial separation and simultaneous utilization of overlapped TSG to enhance electricity *** benefits render a remarkable efficiency of90.8%in solar energy utilization,manifesting in co-generation of solar steam at a fast rate of 2.01 kg m^(-2)-h^(-1)and electricity power of 1.91 W m^(-2)with high *** interfacing the hybrid SIWE with seawater electrolyzer constructs a system for water-electricity-hydrogen co-generation without external electricity *** produces hydrogen at a rapid rate of 1.29 L h^(-1)m^(-2)and freshwater with 22 times lower Na+concentration than the World Health Organization(WHO)threshold.

关键词： Solar-driven interfacial water evaporation Steam generation Electricity generation Seawater