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The clinicopathological and prognostic significance of PD-L1 expression in pancreatic cancer:A meta-analysis

Hepatobiliary & Pancreatic Diseases International 2018年第2期17卷 95-100页

作者： He-Li Gaoa Liang Liua Zi-Hao Qi Hua-xiang Xu Wen-Quan Wang Chun-Tao Wu Shi-Rong Zhang Jin-Zhi Xu Quan-Xing Ni xian-jun yua Department of Pancreatic Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Shanghai Pancreatic Cancer Institute Shanghai 200032China Pancreatic Cancer Institute Fudan UniversityShanghai 200032China

Background: Immunotherapy has shown promise against solid tumors. However, the clinical significance of programmed cell death 1(PD-1) and programmed cell death ligand 1(PD-L1) in pancreatic ductal adenocarcinoma(PDAC) remains unclear. This meta-analysis aimed to analyze the prognostic effect of PD-L1 in *** sources: Electronic search of the Pub Med, Cochrane Library and Web of Science was performed until December 2016. Through database searches, we identified articles describing the relationship between PD-L1 status and PDAC patient prognosis. Meta-analysis was performed to investigate the relationship between PD-1 and overall survival(OS).Results: Nine studies with 989 PDAC patients were included for PD-L1 expression analysis. And 5 studies with 688 PDAC patients were included in the prognostic analysis. The PD-L1 positive rate measured by immunohistochemistry(IHC) was higher than that measured by polymerase chain reaction(PCR)(P < 0.001). PDAC patients with high expression levels of PD-L1 had significantly reduced OS(HR = 2.34;95% CI: 1.78–3.08). Subgroup analysis showed that the prognostic effect of PD-L1 levels was similar between the IHC and PCR methods. The PD-L1 positive rate was associated with PDAC T stages; the PD-L1 positive rate in the T3–4 group was higher than that in the T1-2 group(OR = 0.37; P = 0.001).Conclusions: High PD-L1 expression levels predicted a poor prognosis in PDAC patients. Thus, PD-L1 status helps determine treatment in PDAC patients.

关键词： Pancreatic ductal adenocarcinoma Programmed cell death ligand 1 Prognosis Meta-analysis

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Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

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Chinese Journal of Polymer Science 2024年第2期42卷 256-266,I0010页

作者： Can-Can Zhang jun-Long Yang Ya-Jiang Huang Guang-xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction

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Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative

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Petroleum Science 2024年第2期21卷 1429-1443页

作者： Bao-jun Tang Chang-Jing Ji Yu-xian Zheng Kang-Ning Liu Yi-Fei Ma jun-Yu Chen Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing100081China School of Management and Economics Beijing Institute of TechnologyBeijing100081China Collaborative Innovation Center of Electric Vehicles in Beijing BeijingChina Sustainable Development Research Institute for Economy and Society of Beijing BeijingChina Institute of Carbon Neutrality ShanghaiTech UniversityShanghai201210China

With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.

关键词： Belt and Road Initiative Oil and Gas Investment Risk assessment

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A 27 GHz,simple 2-bit 1×8 phased array

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Journal of Electronic Science and Technology 2024年第3期22卷 26-34页

作者： jun-xian Liu Yun-Ying Man Hao Yang Peng Yang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This study demonstrates a simple 2-bit phased array operating at 27 GHz that supports one-dimensional beam scanning with left-handed circular polarization(LHCP).The antenna is constructed using a compact four-layer printed circuit board(PCB)structure,consisting of a 90°phase shifter layer with microstrip structures,a ground(GND)layer,a direct current(DC)control layer,and a circularly polarized annular radiation patch layer with 1-bit phase *** on the proposed unit structure,a 1×8 array with half-wavelength inter-element spacing was designed and *** results show that the array achieves a peak gain of 10.23 dBi and is capable of beam scanning within±50°.

关键词： 27 GHz 2-bit P-i-n diodes Phased array Reconfigurable antennas

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FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT

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Nuclear Science and Techniques 2024年第3期35卷 96-108页

作者： Wei Jiang Ping Cao Yi-Ming Wu xian-Ke Liu Zhu-jun Fang Zhi-Yong Zhang Bin Shi jun Chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas *** address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber *** method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined *** performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data *** experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 *** beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction *** online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT.

关键词： Position reconstruction FPGA Readout electronics Neutron flux spatial distribution

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Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： Wen-Dong Liu Xiao Tang jun-An Feng Chao-Yue Zhang Hao Liu Chuan Shi Xiao-xian Zhao Jian-jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application ***,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of *** response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of ***,vacancy engineering has gained the attention of researchers due to its unique electronic *** review aims to analyze the application of vacancy engineering in ***,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been ***,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,*** latest applications of vacancy engineering in LSBs are also summarized in this ***,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

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Effect of Phase Separation Size on the Properties of Self-healing Elastomer

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Chinese Journal of Polymer Science 2024年第6期42卷 798-804页

作者： jun Xu Lei Zhu xian-Qi Feng Cong Sui Wen-Peng Zhao Shou-Ke Yan School of Chemical Engineering Qingdao University of Science&TechnologyQingdao266042China College of Engineering Yanching institute of TechnologyLangfang065210China Key Laboratory of Rubber-plastics Qingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Regulation of phase structure has been recognized as one of the most effective ways to fabricate self-healing polymers with high mechanical *** mechanical properties of the resultant polymers are certainly affected by the size of separated phase ***,the study on this aspect is absence,because it can hardly exclude the influence of variation in monomer proportion required for tuning the separated phase ***,we report the first study on tuning the phase size through reversible addition-fragmentation chain transfer(RAFT)polymerization without changing the proportion of *** expected,the size of separated phase has been successfully mediated from 15 nm to 9 nm by tuning the molecular weight of the chain transfer *** is found that the mechanical strength and the self-healing efficiency of the resultant polymers increase simultaneously with the decrease of phase *** study on the formation kinetics of hydrogen bonds reveals that the decrease of phase size can facilitate the re-bonding rate of hydrogen bonds,even if the migration of polymer chains is restricted.

关键词： Self-healing polymers Phase separation Reversible addition-fragmentation chain transfer

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Cytoplasmic FKBPs are involved in molting and metamorphosis through regulating the nuclear localization of EcR

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Insect Science 2024年第3期31卷 759-772页

作者： xian Zhang Qiao-Ran Wang Qian Wu jun Gu Li-Hua Huang Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology School of Life SciencesSouth China Normal UniversityGuangzhouChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouChina

Molting and metamorphosis are important physiological processes in insects that are tightly controlled by ecdysone receptor(EcR)through the 20-hydroxyecdysone(20E)signaling *** is a steroid nuclear receptor(SR).Several FK506-binding proteins(FKBPs)have been identified from the mammal SR complex,and are thought to be involved in the subcellular trafficking of ***,their roles in insects are poorly *** explore whether FKBPs are involved in insect molting or metamorphosis,we injected an FKBP inhibitor(FK506)into a lepidopteran insect,Spodoptera litura,and found that molting was inhibited in 61.11%of the larvae,and that the time for larvae to pupate was significantly extended.A total of 10 FKBP genes were identified from the genome of *** and were clustered into 2 distinct groups,according to their subcellular localization,with FKBP13 and FKBP14 belonging to the endoplasmic reticulum(ER)group and with the other members belonging to the cytoplasmic(Cy)*** the CyFKBPs were significantly upregulated in the prepupal or pupal stages,with the opposite being observed for the ER group ***506 completely blocked the transfer of EcR to the nucleus under 20E induction,and significantly downregulated the transcriptional expression of many 20E signaling genes.A similar phenomenon was observed after RNA interference of2 CyFKBPs(FKBP45 and FKBP12b),but not for *** together,our data indicate that the cytoplasmic FKBPs,especially FKBP45 and FKBP12b,mediate the nuclear localization of EcR,thereby regulating the 20E signaling and ultimately affecting molting and metamorphosis in insects.

关键词： EcR FKBP metamorphosis molting RNAi subcellular localization

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Differences and identification on multi-time hydrocarbon generation of carboniferous-permian coaly source rocks in the Huanghua Depression,Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 765-776页

作者： Jin-jun Xu xian-Gang Cheng Shu-Nan Peng jun-Cai Jiang Qi-Long Wu Da Lou Fu-Qi Cheng La-Mei Lin National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShandongChina PetroChina Dagang Oilfield Company Tianjin300280China

Coal is a solid combustible mineral,and coal-bearing strata have important hydrocarbon generation potential and contribute to more than 12%of the global hydrocarbon ***,the deposition and hydrocarbon evolution process of ancient coal-bearing strata is characterized by multiple geological times,leading to obvious distinctions in their hydrocarbon generation potential,geological processes,and production,which affect the evaluation and exploration of hydrocarbon resources derived from coaly source rocks *** study aimed to identify the differences on oil-generated parent macerals and the production of oil generated from different coaly source rocks and through different oil generation *** with the analysis of previous tectonic burial history and hydrocarbon generation history,high-temperature and high-pressure thermal simulation experiments,organic geochemistry,and organic petrology were performed on the Carboniferous-Permian(C-P)coaly source rocks in the Huanghua Depression,Bohai Bay *** oil-generated parent macerals of coal's secondary oil generation process(SOGP)were mainly hydrogen-rich collotelinite,collodetrinite,sporinite,and cutinite,while the oil-generated parent macerals of tertiary oil generation process(TOGP)were the remaining small amount of hydrogen-rich collotelinite,sporinite,and cutinite,as well as dispersed soluble organic matter and unexhausted residual *** with coal,the oil-generated parent macerals of coaly shale SOGP were mostly sporinite and *** part of hydrogen-poor vitrinite,lacking hydrocarbon-rich macerals,and macerals of the TOGP,in addition to some remaining cutinite and a small amount of crude oil and bitumen from SOGP contributed to the oil *** results indicated that the changes in oil yield had a good junction between SOGP and TOGP,both coal and coaly shale had higher SOGP aborted oil yield than TOGP starting yield,and coaly shale TOGP peak oil yield was low

关键词： Thermal simulation Multi-time oil generation processes Coaly source rock Carboniferous-permian Huanghua Depression

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Interpretation and characterization of rate of penetration intelligent prediction model

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Petroleum Science 2024年第1期21卷 582-596页

作者： Zhi-jun Pei xian-Zhi Song Hai-Tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-Sheng Li College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology Co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling *** the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its *** study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation *** leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector *** FNN model is linearly characterized through further simplification,enabling its interpretation and *** proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim *** results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally *** relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data *** the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation ***,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well *** established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

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