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Construction of coal pitch-based HA-K grafted poly condensates and their excellent anti-temperature and viscosity-reducing properties

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Petroleum Science 2024年第4期21卷 2806-2816页

作者： Jing Tan Wei Zhang Xiu-Ling Yan hao Zhou Sher Bahadar Khan Seitkhan Azat Shi-You Yan hao-jie ma Xin-Tai Su Xinjiang Key Laboratory of Clean Conversion and High Value Utilization of Biomass Resources College of Chemistry and Chemical Engineering Yili Normal University School of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling South China University of Technology Drilling Fluid Branch of CNPC Xibu Drilling Engineering Company Limited Department of Chemistry Faculty of Science King Abdulaziz University PO Box 80203 Faculty of Chemistry and Chemical Technology Al-Farabi Kazakh National University Urumchi Huatailong Chemical Additives Co. Ltd.

Humic acids(HAs) are widely used as filtrate and viscosity reducers in drilling fluids. However, their practical utility is limited due to poor stability in salt resistance and high-temperature resistance. Hightemperature coal pitch(CP) is a by-product from coal pyrolysis above 650.C. The substance's molecular structure is characterized by a dense arrangement of aromatic hydrocarbon and alkyl substituents. This unique structure gives it unique chemical properties and excellent drilling performance, surpassing traditional humic acids in drilling operations. Potassium humate is prepared from CP(CP-HA-K) by thermal catalysis. A new type of high-quality humic acid temperature-resistant viscosity-reducer(Graft CP-HA-K polymer) is synthesized with CP-HA-K, hydrolyzed polyacrylonitrile sodium salt(Na-HPAN),urea, formaldehyde, phenol and acrylamide(AAM) as raw materials. The experimental results demonstrate that the most favorable conditions for the catalytic preparation of CP-HA-K are 1 wt% catalyst dosage, 30 wt% KOH dosage, a reaction temperature of 250.C, and a reaction time of 2 h, resulting in a maximum yield of CP-HA-K of 39.58%. The temperature resistance of the Graft CP-HA-K polymer is measured to be 177.39.C, which is 55.39.C higher than that of commercial HA-K. This is due to the abundant presence of amide, hydroxyl, and amine functional groups in the Graft CP-HA-K polymer,which increase the length of the carbon chains, enhance the electrostatic repulsion on the surface of solid particles. After being aged to 120.C for a specified duration, the Graft CP-HA-K polymer demonstrates significantly higher viscosity reduction(42.12%) compared to commercial HA-K(C-HA-K). Furthermore,the Graft CP-HA-K polymer can tolerate a high salt concentration of 8000 mg.L-1, measured after the addition of optimum amount of 3 wt% Graft CP-HA-K polymer. The action mechanism of Graft CP-HA-K polymer on high-temperature drilling fluid is that the Graft CP-HA-K polymer can increase the re

关键词： Viscosity breaker Heat resistance Base mud Graft CP-HA-K polymer CP Salt resistance

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Characterization of Porcine Reproductive and Respiratory Syndrome Virus Deletion Mutant

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Agricultural Sciences in China 2008年第11期7卷 1379-1386页

作者： CHEN hao-tai ZHANG jie ma Li-na LIU Yong-sheng State Key Laboratory of Veterinary Etiological Biology/Key Laboratory of Animal Virology Ministry of Agriculture/Key Laboratory of Veterinary Public Health Ministry of Agriculture/Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou 730046 P.R.China

The genome of the isolate of porcine reproductive and respiratory syndrome virus （PRRSV） from China, designated HPBEDV, was sequenced and analyzed. The size of the genome of HPBEDV was 15 334 nucleotides （nt）. Comparative analysis of HPBEDV with the genomic sequences of the domestic and other isolates （JXA 1, HUN4, CH-1 a, B J-4, VR2332, and LV） revealed that HPBEDV shared 98.4, 98.0, 89.0, 88.7, and 88.6% identity with the American strain JXA1, HUN4, CH- 1a, BJ-4, and VR2332, respectively, but only 54.7% identity with the European reference strain Lelystad virus. The NSP2 gene had 2 850 nt and encoded 950 amino acids （aa）, with two discontiguous deletions of 1 aa and 29 aa at positions 482 and 534-562, respectively, relative to VR-2332. Also, phylogenetic analysis with the published PRRSV genomic sequences indicated that the newly emerging isolate form a clade with the VR-2332 isolates. Therefore, HPBEDV was a novel strain with deletions in NSP2 gene.

关键词： porcine reproductive and respiratory syndrome virus deletion mutant genome phylogenetic tree

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Effects of nutrient limitations on the sinking velocity of Thalassiosira weissflogii

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Acta Oceanologica Sinica 2024年第6期43卷 163-172页

作者： jie Zhu Qiang hao Wei Zhang Yingying ma Jiangning Zeng Ocean College Zhejiang UniversityZhoushan 316000China Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China Key Laboratory of marine Ecosystem Dynamics Ministry of Natural ResourcesHangzhou 310012China Zhejiang Key Laboratory of Nearshore Engineering Environment and Ecological Security Hangzhou 310012China Tianjin Key Lab of Aqua-Ecology and Aquaculture College of FisheriesTianjin Agricultural UniversityTianjin 300384China

The sinking of diatoms is critic al to the formation of oceanic biological pumps and coastal hypoxic ***,little is known about the effects of different nutrient restrictions on diatom *** this study,we measured the sinking velocity(SV) of Thalassiosira weissflogii using a new phytoplankton video observation instrument and analyzed major biochemical components under varying nutrient *** results showed that the SV of *** under different nutrient limitation conditions varied *** highest SV of(1.77±0.02) m/d was obtained under nitrate limitation,signific antly surpassing that under phosphate limitation at(0.98±0.13) m/*** the nutrient limitation was released,the SV steadily decreased to(0.32±0.03) m/d and(0.15±0.05) m/d,***;under conditions with limited nitrate and phosphate concentrations,the SV values of *** significantly positively correlated with the lipid content(P marily related to the intracellular compo sition,which is controlled by nutrient conditions but did not significantly correlate with transparent extracellular polymer and biosilica *** results of this study help to understand the regulation of the vertical sinking process of diatoms by nutrient restriction and provide new insights into phytoplankton dynamics and their relationship with the marine nutrient structure.

关键词： nutrient limitation Thalassiosira weissflogii sinking velocity biochemical component lipid content

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Predicting Acute Mountain Sickness Using Regional Sea-Level Cerebral Blood Flow

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Biomedical and Environmental Sciences 2024年第8期37卷 887-896页

作者： hao Zhang jie Feng Shiyu Zhang Wenjia Liu Lin ma Chinese PLA Medical School Beijing 100853China Department of Radiology First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea *** CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS *** analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)*** The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(Pmay be used for prediction in male volunteers using non-invasive 3D-pCASL.

关键词： Acute mountain sickness High-altitude headache Cerebral blood flow Arterial spin labeling magnetic resonance imaging

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Realizing high initial Coulombic efficiency in manganese-based layered oxide cathodes for sodium-ion batteries via P2/O'3 biphasic structure optimization

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Rare Metals 2024年第5期43卷 2093-2102页

作者： Bo Peng Zi-hao Zhou Ping Xuan jie Xu Lian-Bo ma School of materials Science and Engineering Anhui University ofTechnologyMa'anshan 243002China Anhui Product Quality Supervision&Inspection Research Institute Hefei 230051China

Mn-based layered oxides are among the most promising cathode materials for sodium-ion batteries owing to the advantages of abundance,environmenta friendliness,low cost and high specific capacity.P2 and O'3 are two representative structures of Mn-based layered ***,the P2 structure containing insufficien Na generally exhibits low initial charge capacity,while O'3structure with sufficient Na delivers high initial charge capacity but poor cycle *** study prepared a multitude of Na_(x)MnO_(2)(x=0.7,0.8,0.9)cathode materials with varying P2/O'3 ratios and further investigated their electrochemical *** optimized Na_(0.8)MnO_(2) comprising 69.9 wt%O'3 and 30.1 wt%P2 phase,exhibited relatively balanced specific capacity,Coulombic efficiency and cycle ***,it achieved a high specific capacity of 128.9 mah·g^(-1) with an initia Coulombic efficiency of 98.2%in half-cell configuration The Na_(0.8)MnO_(2)//hard carbon full cell also achieved a high specific capacity of 126.7 mah·g^(-1) with an initia Coulombic efficiency of 98.9%.Moreover,the capacity fading mechanism was revealed by combining in-situ and ex-situ X-ray *** findings of this study provide theoretical guidance for further modification design of Mnbased layered cathodes.

关键词： Sodium-ion batteries Cathode materials Mn-based layered oxides P2/0'3 composites

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Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI Shasha LI hao XU jie YU Jun ma Huijun LIU Jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

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PPP1R14A is Associated with Immunotherapy Resistance in Head and Neck Squamous Cell Carcinoma Identified by Single-Cell and Bulk RNA-Sequencing

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Chinese Medical Sciences Journal 2024年第2期39卷 111-121页

作者： Jun-jie ma Lei Zhang Jin Lu hao-Xuan Zhang Department of Clinical Medicine Bengbu Medical UniversityBengbu 233030AnhuiChina Department of General Surgery The Second Affiliated Hospital of Bengbu Medical UniversityBengbu 233030AnhuiChina Department of Human Anatomy Bengbu Medical UniversityBengbu 233030AnhuiChina Anhui Key Laboratory of Computational Medicine and Intelligent Health Bengbu Medical UniversityBengbu 233030AnhuiChina

Objective To identify nivolumab resistance-related genes in patients with head and neck squamous cell carcinoma(HNSCC)using single-cell and bulk RNA-sequencing *** The single-cell and bulk RNA-sequencing data downloaded from the Gene Expression Omnibus database were analyzed to screen out differentially expressed genes(DEGs)between nivolumab resistant and nivolumab sensitive patients using R *** Least Absolute Shrinkage Selection Operator(LASSO)regression and Recursive Feature Elimination(RFE)algorithm were performed to identify key genes associated with nivolumab *** enrichment of DEGs was analyzed with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes *** relationships of key genes with immune cell infiltration,differentation trajectory,dynamic gene expression profiles,and ligand-receptor interaction were *** We found 83 *** were mainly enriched in T-cell differentiation,PD-1 and PD-L1 checkpoint,and T-cell receptor *** six key genes identified using machine learning algorithms,only PPP1R14A gene was differentially expressed between the nivolumab resistant and nivolumab sensitive groups both before and after immunotherapy(P0,Pmab in HNSCC ***,PPP1R14A may be a target to ameliorate nivolumab resistance of HNSCC patients.

关键词： PPP1R14A head and neck squamous cell carcinoma immunotherapy drug resistance

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3D simulation of image-defined complex internal features using the numerical manifold method

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Science China(Technological Sciences) 2024年第4期67卷 1023-1039页

作者： WU jie ma GuoWei School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Tianjin Key Laboratory for Prefabricated Building and Intelligent Construction Tianjin 300401China

The numerical simulation of internal features,such as inclusions and voids,is important to analyze their impact on the performance of composite ***,the complex geometries of internal features and the induced continuous-discontinuous(C-D)deformation fields are challenges to their numerical *** this study,a 3D approach using a simple mesh to simulate irregular internal geometries is developed for the first *** the help of a developed voxel crack model,image models that are efficient when recording complex geometries are directly imported into the *** reconstructions,which are usually labor-intensive,are excluded from this ***,using image models as the geometric input,image processing techniques are applied to detect material interfaces and develop contact ***,the C-D deformations of the complex internal features are directly calculated based on the numerical manifold *** accuracy and convergence of the developed3D approach are examined based on multiple *** 3D C-D simulation of sandstones with naturally formed complex microfeatures demonstrates the capability of the developed approach.

关键词： 3D continuous-discontinuous simulation image-based simulation complex internal features numerical manifold method voxel crack model structured mesh

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Texture and Se vacancy optimization induces high thermoelectric performance in Bi_(2)Se_(3) flexible thin films

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Rare Metals 2024年第6期43卷 2796-2804页

作者： Dong-Wei Ao Wei-Di Liu Yue-Xing Chen Fan ma Yi-jie Gu Zhuang-hao Zheng School of machinery and Automation Weifang UniversityWeifang 261061China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbane 4072Australia Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China School of materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China

Bi_(2)Se_(3)-based flexible thin film with high thermoelectric performance is promising for the waste heat recovery *** this work,a novel post-selenization method is employed to prepare n-type Bi_(2)Se_(3)flexible thin films with highly textured *** strengthened texture and Se vacancy optimization can be simultaneously achieved by optimizing the selenization *** highly oriented texture leads to the increased carrier mobility and results in a high electric conductivity of~290.47 S·cm^(-1)at 623 ***,a high Seebeck coefficient(>110μW·K-1)is obtained due to the reduced carrier concentration,induced by optimizing vacancy ***,a high power factor of 3.49μW·cm^(-1)·K^(-2)at 623 K has been achieved in asprepared highly-bendable Bi_(2)Se_(3)flexible thin films selenized at 783 *** study introduces an effective post-selenization method to tune the texture structure and vacancies of Bi_(2)Se_(3)flexible thin films,and correspondingly achieves high thermoelectric performance.

关键词： Thermoelectric Bi_(2)Se_(3) Flexible thin film Post-selenization

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Single-cell RNA-seq reveals the transcriptional program underlying tumor progression and metastasis in neuroblastoma

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Frontiers of Medicine 2024年第4期18卷 690-707页

作者： Zhe Nian Dan Wang hao Wang Wenxu Liu Zhenyi ma jie Yan Yanna Cao jie Li Qiang Zhao Zhe Liu Department of Immunology School of Basic Medical SciencesTianjin Medical UniversityTianjin300070China Zhejiang Key Laboratory of Medical Epigenetics Department of Cell BiologySchool of Basic Medical SciencesHangzhou Normal UniversityHangzhou311121China Department of Pediatric Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin300060China Collaborative Innovation Center for Cancer Personalized Medicine Nanjing Medical UniversityNanjing211166China

Neuroblastoma(NB)is one of the most common childhood *** percent of patients present with widely disseminated clinical signs at diagnosis and exhibit poor ***,the molecular mechanisms triggering NB metastasis remain largely *** this study,we generated a transcriptomic atlas of 15447 NB cells from eight NB samples,including paired samples of primary tumors and bone marrow *** used time-resolved analysis to chart the evolutionary trajectory of NB cells from the primary tumor to the metastases in the same patient and identified a common‘starter’subpopulation that initiates tumor development and ***‘starter’population exhibited high expression levels of multiple cell cycle-related genes,indicating the important role of cell cycle upregulation in NB tumor *** addition,our evolutionary trajectory analysis demonstrated the involvement of partial epithelial-to-mesenchymal transition(p-EMT)along the metastatic route from the primary site to the bone *** study provides insights into the program driving NB metastasis and presents a signature of metastasis-initiating cells as an independent prognostic indicator and potential therapeutic target to inhibit the initiation of NB metastasis.

关键词： single-cell RNA sequencing metastasis neuroblastoma epithelial-to-mesenchymal transition

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