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Identification and Validation of Novel Biomarkers Related to the Calcium Metabolism Pathway in Hypertension Patients Based on Comprehensive Bioinformatics Methods
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作者 Xiangguang Chang lei guo +2 位作者 Liying Zou Yazhao Ma Jilin Feng 《Health》 2024年第3期173-186,共14页
Background: Hypertension is a universal risk factor for cardiovascular diseases and is thus the leading cause of death worldwide. The identification of novel prognostic and pathogenesis biomarkers plays a key role in ... Background: Hypertension is a universal risk factor for cardiovascular diseases and is thus the leading cause of death worldwide. The identification of novel prognostic and pathogenesis biomarkers plays a key role in disease management. Methods: The GSE145854 and GSE164494 datasets were downloaded from the Gene Expression Omnibus (GEO) database and used for screening and validating hypertension signature genes, respectively. Gene Ontology (GO) enrichment analysis was performed on the differentially expressed genes (DEGs) related to calcium ion metabolism in patients with hypertension. The core genes related to immune infiltration were analyzed and screened, and the activity of the signature genes and related pathways was quantified using gene set enrichment analysis (GSEA). The infiltration of immune cells in the blood samples was analyzed, and the DEGs that were abnormally expressed in the clinical blood samples of patients with hypertension were verified via RT-qPCR. Results: A total of 176 DEGs were screened. GO showed that DEGs was involved in the regulation of calcium ion metabolism in biological processes (BP), actin mediated cell contraction, negative regulation of cell movement, and calcium ion transmembrane transport, and in the regulation of protease activity in molecular functions (MF). KEGG analysis revealed that the DEGs were involved mainly in the cGMP-PKG signaling pathway, ubiquitin-protein transferase, tight junction-associated proteins, and the regulation of myocardial cells. MF analysis revealed the immune infiltration function of the cells. RT-qPCR revealed that the expression of Cacna1d, Serpine1, Slc8a3, and Trpc4 was up regulated in hypertension, the expression of Myoz2 and Slc25a23 was down regulated. Conclusion: Cacna1d, Serpine1, Slc8a3, Trpc4, Myoz2 and Slc25a23 may be involved in the regulation of calcium metabolism pathways and play key roles in hypertension. These differentially expressed calcium metabolism-related genes may serve as prognostic markers of hypertension. 展开更多
关键词 HYPERTENSION Biomarkers Differentially Expressed Genes Ca2+ Metabo-lism Bioinformatics Analysis
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Identification and Validation of Vascular-Associated Biomarkers for the Prognosis and Potential Pathogenesis of Hypertension Using Comprehensive Bioinformatics Methods
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作者 Xiangguang Chang lei guo +2 位作者 Liying Zou Yazhao Ma Jilin Feng 《World Journal of Cardiovascular Diseases》 CAS 2024年第3期115-128,共14页
Background: Hypertension, also known as increased blood pressure, is a phenomenon in which blood flows in blood vessels and causes persistently higher-than-normal pressure on the vessel wall. The identification of nov... Background: Hypertension, also known as increased blood pressure, is a phenomenon in which blood flows in blood vessels and causes persistently higher-than-normal pressure on the vessel wall. The identification of novel prognostic and pathogenesis biomarkers plays a key role in the management of hypertension. Methods: The GSE7483 and GSE75815 datasets from the gene expression omnibus (GEO) database were used to identify the genes associated with hypertension that were differentially expressed genes (DEGs). The functional role of the DEGs was elucidated by gene body (GO) enrichment analysis. In addition, we performed an immune infiltration assay and GSEA on the DEGs of hypertensive patients and verified the expression of novel DEGs in the blood of hypertensive patients by RT-qPCR. Results: A total of 267 DEGs were identified from the GEO database. GO analysis revealed that these genes were associated mainly with biological processes such as fibroblast proliferation, cell structural organization, extracellular matrix organization, vasculature development regulation, and angiogenesis. We identified five possible biomarkers, Ecm1, Sparc, Sphk1, Thbsl, and Mecp2, which correlate with vascular development and angiogenesis characteristic of hypertension by bioinformatics, and explored the clinical expression levels of these genes by RT-qPCR, and found that Sparc, Sphk1, and Thbs1 showed significant up-regulation, in agreement with the results of the bioinformatics analysis. Conclusion: Our study suggested that Sparc, Sphk1 and Thbs1 may be potential novel biomarkers for the diagnosis, treatment and prognosis of hypertension and that they are involved in the regulation of vascular development and angiogenesis in hypertension. 展开更多
关键词 HYPERTENSION Biomarkers Differentially Expressed Genes Vascular Development and Angiogenesis Bioinformatics Analysis
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New process for treating boron-bearing iron ore by flash reduction coupled with magnetic separation
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作者 Qipeng Bao lei guo +4 位作者 Hong Yong Sohn Haibin Zuo Feng Liu Yongliang Gao Zhancheng guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期473-484,共12页
Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional beneficiation.Th... Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional beneficiation.This study proposed a new treatment called flash reduction-melting separation(FRMS)for boron-bearing iron concentrates.In this method,the concentrates were first flash-reduced at the temperature under which the particles melt,and the slag and the reduced iron phases disengaged at the particle scale.Good reduc-tion and melting effects were achieved above 1550℃.The B_(2)O_(3) content in the separated slag was over 18wt%,and the B content in the iron was less than 0.03wt%.The proposed FRMS method was tested to investigate the effects of factors such as ore particle size and tem-perature on the reduction and melting steps with and without pre-reducing the raw concentrate.The mineral phase transformation and morphology evolution in the ore particles during FRMS were also comprehensively analyzed. 展开更多
关键词 LUDWIGITE boron-bearing iron concentrate flash reduction melting separation BORON
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Mechanisms of tumor immunosuppressive microenvironment formation in esophageal cancer
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作者 Xiao-Jun Zhang Yan Yu +3 位作者 He-Ping Zhao lei guo Kun Dai Jing Lv 《World Journal of Gastroenterology》 SCIE CAS 2024年第16期2195-2208,共14页
As a highly invasive malignancy,esophageal cancer(EC)is a global health issue,and was the eighth most prevalent cancer and the sixth leading cause of cancerrelated death worldwide in 2020.Due to its highly immunogenic... As a highly invasive malignancy,esophageal cancer(EC)is a global health issue,and was the eighth most prevalent cancer and the sixth leading cause of cancerrelated death worldwide in 2020.Due to its highly immunogenic nature,emerging immunotherapy approaches,such as immune checkpoint blockade,have demonstrated promising efficacy in treating EC;however,certain limitations and challenges still exist.In addition,tumors may exhibit primary or acquired resistance to immunotherapy in the tumor immune microenvironment(TIME);thus,understanding the TIME is urgent and crucial,especially given the importance of an immunosuppressive microenvironment in tumor progression.The aim of this review was to better elucidate the mechanisms of the suppressive TIME,including cell infiltration,immune cell subsets,cytokines and signaling pathways in the tumor microenvironment of EC patients,as well as the downregulated expression of major histocompatibility complex molecules in tumor cells,to obtain a better understanding of the differences in EC patient responses to immunotherapeutic strategies and accurately predict the efficacy of immunotherapies.Therefore,personalized treatments could be developed to maximize the advantages of immunotherapy. 展开更多
关键词 Esophageal cancer Esophageal squamous cell carcinoma Esophageal adenocarcinoma Tumor immune microenvironment IMMUNOSUPPRESSION Immunotherapy
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Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows
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作者 Ke Wang Ya Wang +11 位作者 lei guo Yong Zhuo Lun Hua Lianqiang Che Shengyu Xu Ruinan Zhang Jian Li Bin Feng Zhengfeng Fang Xuemei Jiang Yan Lin De Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期362-373,共12页
Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracte... Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets. 展开更多
关键词 Amino acids SOWS Soybean meal Standardized ileal digestibility
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冻融干湿循环下硫酸盐渍土的微观孔隙研究
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作者 张卫兵 李晓 +2 位作者 雷过 刘臻祥 周鑫磊 《地下空间与工程学报》 CSCD 北大核心 2023年第2期465-473,共9页
为研究冻融干湿循环对宁夏地区硫酸盐渍土微观孔隙结构的影响,在6次冻融干湿循环后,对试样进行SEM和MIP试验,借助ImageJ2X图像处理技术,从表观孔隙率、孔隙分布和孔隙分形维数3个角度分析其微观孔隙结构。结果表明:(1)经历6次冻融干湿... 为研究冻融干湿循环对宁夏地区硫酸盐渍土微观孔隙结构的影响,在6次冻融干湿循环后,对试样进行SEM和MIP试验,借助ImageJ2X图像处理技术,从表观孔隙率、孔隙分布和孔隙分形维数3个角度分析其微观孔隙结构。结果表明:(1)经历6次冻融干湿循环后,含盐量较低(S≤1%)时,不同压实度下硫酸盐渍土的表观孔隙率随含盐量的增加均呈现先增大后减小的变化趋势,并在0.5%时达到峰值,1%时处于低谷;含盐量大于1%时,低压实度(K<95%)土体表观孔隙率随含盐量增加持续增大,而高压实度(K≥95%)土体则呈现先小幅增大后减小的变化趋势;(2)相较于未经冻融干湿循环的情况,土体最终表观孔隙率均有所增大。为提高工程的耐久性,建议硫酸盐渍土地基的压实度宜大于等于95%。(3)随含盐量的增加,孔隙孔径的变化主要集中在3~40 um区间内,孔隙分布的变化也主要体现在大孔隙、中孔隙上,且表观孔隙率与大孔隙体积百分含量变化基本一致;(4)基于MIP数据拟合得到土体孔隙分形维数随含盐量的增加呈上下波动,且其与表观孔隙率、大孔隙体积百分含量变化趋势相反。本研究有助于丰富硫酸盐渍土的微观理论,为硫酸盐渍土地区的工程建设提供理论支撑。 展开更多
关键词 硫酸盐渍土 冻融干湿循环 电镜扫描 压汞试验 微观孔隙结构
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飞秒激光白内障手术联合PanOptix三焦点人工晶状体植入术的疗效 被引量:3
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作者 郭磊 梁先军 +2 位作者 张希乔 徐艳雪 林英杰 《国际眼科杂志》 CAS 北大核心 2023年第2期312-315,共4页
目的:观察飞秒激光白内障手术联合PanOptix三焦点人工晶状体植入术的临床疗效。方法:回顾性研究。选取2020-08/2021-08于我院行飞秒激光白内障手术联合PanOptix三焦点人工晶状体植入术的白内障患者22例26眼,随访至术后3mo,观察手术前后... 目的:观察飞秒激光白内障手术联合PanOptix三焦点人工晶状体植入术的临床疗效。方法:回顾性研究。选取2020-08/2021-08于我院行飞秒激光白内障手术联合PanOptix三焦点人工晶状体植入术的白内障患者22例26眼,随访至术后3mo,观察手术前后远中近视力、像差、斯特里尔比值(SR)及调制传递函数截止频率(MTF-cutoff)变化情况,绘制术后1mo离焦曲线,评估术后3mo患者视觉质量和满意度。结果:术后1d,1wk,1、3mo,纳入患者远中近视力均优于0.1(LogMAR),与术前相比显著改善(均P<0.01)。术后1mo离焦曲线在+0.5~-3.0D之间曲线过渡平缓,视力均优于0.63(小数视力)。术后1d,1wk全眼总像差、球差均明显低于术前,SR、MTF-cutoff均明显高于术前(均P<0.05)。术后3mo,纳入患者看远中近距离时均无需戴镜,整体满意度高,视觉质量良好。结论:飞秒激光白内障手术联合PanOptix三焦点人工晶状体植入术可使患者获得舒适满意的全程视力。 展开更多
关键词 飞秒激光白内障手术 PanOptix三焦点人工晶状体 像差 斯特里尔比值 调制传递函数截止频率 离焦曲线
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Updates on global epidemiology,risk and prognostic factors of gastric cancer 被引量:7
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作者 Wen-Juan Yang He-Ping Zhao +5 位作者 Yan Yu Ji-Han Wang lei guo Jun-Ye Liu Jie Pu Jing Lv 《World Journal of Gastroenterology》 SCIE CAS 2023年第16期2452-2468,共17页
Gastric cancer(GC)is defined as the primary epithelial malignancy derived from the stomach,and it is a complicated and heterogeneous disease with multiple risk factors.Despite its overall declining trend of incidence ... Gastric cancer(GC)is defined as the primary epithelial malignancy derived from the stomach,and it is a complicated and heterogeneous disease with multiple risk factors.Despite its overall declining trend of incidence and mortality in various countries over the past few decades,GC remains the fifth most common malignancy and the fourth leading cause of cancer-related death globally.Although the global burden of GC has shown a significant downward trend,it remains severe in certain areas,such as Asia.GC ranks third in incidence and mortality among all cancer types in China,and it accounts for nearly 44.0%and 48.6%of new GC cases and GC-related deaths in the world,respectively.The regional differences in GC incidence and mortality are obvious,and annual new cases and deaths are increasing rapidly in some developing regions.Therefore,early preventive and screening strategies for GC are urgently needed.The clinical efficacies of conventional treatments for GC are limited,and the developing understanding of GC pathogenesis has increased the demand for new therapeutic regimens,including immune checkpoint inhibitors,cell immunotherapy and cancer vaccines.The present review describes the epidemiology of GC worldwide,especially in China,summarizes its risk and prognostic factors,and focuses on novel immunotherapies to develop therapeutic strategies for the management of GC patients. 展开更多
关键词 Gastric cancer EPIDEMIOLOGY Risk factors PROGNOSIS Treatment IMMUNOTHERAPY
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调控Co_(2)C局域浸润环境实现高碳效合成气直接制烯烃
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作者 刘培功 林铁军 +5 位作者 郭磊 刘晓哲 龚坤 尧泰真 安芸蕾 钟良枢 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第5期150-163,共14页
合成气转化是实现煤、天然气、生物质、固体废弃物及CO_(2)等非石油含碳资源清洁高效利用的关键过程,可合成多种清洁液体燃料和高附加值化学品,如汽油、柴油、航空煤油、固体石蜡、烯烃、芳烃和含氧化合物等.其中,合成气直接制烯烃(STO... 合成气转化是实现煤、天然气、生物质、固体废弃物及CO_(2)等非石油含碳资源清洁高效利用的关键过程,可合成多种清洁液体燃料和高附加值化学品,如汽油、柴油、航空煤油、固体石蜡、烯烃、芳烃和含氧化合物等.其中,合成气直接制烯烃(STO)具有流程短、能耗低和经济性高等优点,备受学术界和工业界关注.近年来,合成气直接制烯烃取得了突破性进展,发展了基于氧化物-分子筛的双功能路线法以及改性费托路线法.然而,由于目前STO体系所使用的氧化物或者碳化物活性相同时也是水煤气变换(WGS)活性位点,导致反应过程产生30%-50%的CO_(2)副产物,造成较低的碳原子利用效率和烯烃收率,以及尾气产品分离能耗的增加.如何通过催化剂界面和局域环境的调控,创新反应路径,提高烯烃选择性和收率,降低C1副产物选择性已成为重大挑战.本文提出通过发展界面浸润性调控策略,将CoMnAl复合氧化物(CMA)衍生的CO_(2)C活性相与疏水SiO_(2)进行一定尺度的物理耦合,能够将CO_(2)选择性从47.8%降到16.8%,同时催化剂的活性提高30%,总产物中烯烃选择性也提高了~65%,体现出较高的碳效.FI-IR光谱和接触角测试结果表明,疏水基团成功引入到SiO_(2)载体上,并且通过粉末混合的方式获得了同样具备疏水特性的CoMnAl复合催化剂(CMASc).热重(TG-DTG)结果表明,即使样品经过300℃的高温处理,其疏水性仍然能得到保持.X射线衍射(XRD)和高分辨率透射电镜(HRTEM)表征结果表明,复合氧化物的活性中心仍是棱柱状Co_(2)C.进一步表征和探针实验解释了催化剂浸润性调变对Co_(2)C基催化剂FTO性能的影响.CO/H_(2)O-TPSR-MS实验表明,往体系中引入H_(2)O蒸气,CMASc催化剂产生的CO_(2)信号强度远低于单独CMA催化剂的.CO/H_(2)-TPSR-MS实验结果表明,在相同的温度下,CMASc催化剂上产生的H_(2)O信号强度高于CMA,而相应的CO_(2)信号强度则要低很多.在250-400℃,将产生的CO_(2)信号峰面积进行积分,发现CMA产生的CO_(2)浓度是CMASc的2.3倍.利用固定床开展CO/H_(2)和CO/H_(2)O探针切换实验,结果表明,在典型FTO反应条件下引入水蒸气到CMA催化剂体系后,CO转化率和尾气H_(2)/CO比大幅度提高,而CMASc上则出现相反趋势.这些实验证实了H_(2)O分子容易吸附在CMA上发生WGS反应,而在Co_(2)C活性位界面构建局域疏水环境有利于水分子快速转移,并防止其再次吸附.利用CO-DRIFTS和烯烃-H_(2)脉冲实验研究活性和烯烃选择性提高的原因.相比于CMA,CO更容易吸附在疏水CMASc上.H_(2)O的引入会导致CO在两个催化剂的强度变弱,但CMASc上吸附的CO强度仍要高于CMA.这说明活性位点存在水会阻碍CO的吸附,而CMASc上相对干燥的表面更有利于CO吸附及后续活化.调控H_(2)O分压探针实验也在宏观层面上验证了该结论,说明活性中心吸附的H_(2)O会抑制催化活性.丙烯加氢脉冲实验发现,浸润环境可以极大地影响烯烃的吸附和加氢能力.在H_(2)O存在的情况下,丙烯更容易在CMA上发生加氢生成丙烷,而疏水CMASc上丙烯更容易直接脱落,从而提高了烯烃选择性.综上,通过调控Co_(2)C活性位局域疏水环境,可以降低表面H_(2)O的吸附,抑制CO_(2)副产物生成,同时强化CO吸附和烯烃脱附,提高烯烃选择性和收率,这为高碳效Co_(2)C基催化剂的理性设计提供借鉴. 展开更多
关键词 费托合成制烯烃 合成气转化 碳化钴 疏水性 低CO_(2)选择性
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冻融-干湿循环下硫酸盐渍土强度劣化的宏微观响应
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作者 雷过 张卫兵 +2 位作者 李晓 刘臻祥 周鑫磊 《长江科学院院报》 CSCD 北大核心 2023年第6期154-159,165,共7页
冻融-干湿循环是引起硫酸盐渍土强度劣化的主要原因,而土体微观孔隙结构与强度之间有紧密的联系。通过无侧限抗压强度试验、压汞试验、电镜扫描(SEM)试验,采用全局优化法(UGO)分析数据,ImageJ2X处理SEM图像,探究了冻融-干湿循环下硫酸... 冻融-干湿循环是引起硫酸盐渍土强度劣化的主要原因,而土体微观孔隙结构与强度之间有紧密的联系。通过无侧限抗压强度试验、压汞试验、电镜扫描(SEM)试验,采用全局优化法(UGO)分析数据,ImageJ2X处理SEM图像,探究了冻融-干湿循环下硫酸盐渍土强度劣化的宏微观响应关系。结果表明:①冻融-干湿循环作用下,无侧限抗压强度随含盐量呈现先增大后减小的变化趋势,当压实度较低时强度峰值对应的含盐量低;从孔隙分布得出,1~10μm的孔隙占比为强度劣化的阈值,当其占比>50%时强度出现劣化,且劣化现象不可逆。②冻融-干湿作用下的无侧限抗压强度值与微观参数的歪度、结构优度间存在相关性,无侧限抗压强度与歪度呈现正相关,与结构优度呈负相关,且结构优度比歪度对强度影响更加显著。③影响无侧限抗压强度宏观指标劣化程度的微观参数依次为结构优度、歪度、分选系数、平均孔喉半径。本研究从定量分析的层面探究了硫酸盐渍土的宏微观响应关系,为进一步研究盐渍土工程性质提供参考。 展开更多
关键词 强度劣化 宏微观响应 硫酸盐渍土 冻融-干湿循环 无侧限抗压强度试验 压汞试验 电镜扫描试验 全局优化法
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Coupling ferromagnetic ordering electron transfer channels and surface reconstructed active species for spintronic electrocatalysis of water oxidation 被引量:1
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作者 Zexing He Xiaokang Liu +7 位作者 Minghui Zhang lei guo Muhammad Ajmal Lun Pan Chengxiang Shi Xiangwen Zhang Zhen-Feng Huang Ji-Jun Zou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期570-580,I0014,共12页
Sluggish reaction kinetics of oxygen evolution reaction(OER), resulting from multistep proton-coupled electron transfer and spin constriction, limits overall efficiency for most reported catalysts. Herein, using model... Sluggish reaction kinetics of oxygen evolution reaction(OER), resulting from multistep proton-coupled electron transfer and spin constriction, limits overall efficiency for most reported catalysts. Herein, using modeled ZnFe_(2-x)Ni_xO_(4)(0 ≤ x ≤ 0.4) spinel oxides, we aim to develop better OER electrocatalyst through combining the construction of ferromagnetic(FM) ordering channels and generation of highly active reconstructed species. The number of symmetry-breaking Fe–O–Ni structure links to the formation of FM ordering electron transfer channels. Meanwhile, as the number of Ni^(3+)increases, more ligand holes are formed, beneficial for redirecting surface reconstruction. The electro-activated ZnFe_(1.6)Ni_(0.4)O_(4) shows the highest specific activity, which is 13 and 2.5 times higher than that of ZnFe_(2)O_(4) and unactivated ZnFe_(1.6)Ni_(0.4)O_(4), and even superior to the benchmark IrO_(2) under the overpotential of 350 mV. Applying external magnetic field can make electron spin more aligned, and the activity can be further improved to 39 times of ZnFe_(2)O_(4). We propose that intriguing FM exchange-field interaction at FM/paramagnetic interfaces can penetrate FM ordering channels into reconstructed oxyhydroxide layers, thereby activating oxyhydroxide layers as spin-filter to accelerate spin-selective electron transfer. This work provides a new guideline to develop highly efficient spintronic catalysts for water oxidation and other spin-forbidden reactions. 展开更多
关键词 Oxygen evolution reaction Reconstruction mechanism Metal oxyhydroxides Electron transfer channels Ferromagnetic exchange-field penetration
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Study on strength properties and soil behaviour type classification of Huanghe River Delta silts based on variable rate piezocone penetration test
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作者 Yunuo Liu guoqing Lin +3 位作者 Yan Zhang Shenggui Deng lei guo Tao Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期146-158,共13页
Fine-grained silt is widely distributed in the Huanghe River Delta(HRD)in China,and the sedimentary structure is complex,meaning that the clay content in the silt is variable.The piezocone penetration test(CPTu)is the... Fine-grained silt is widely distributed in the Huanghe River Delta(HRD)in China,and the sedimentary structure is complex,meaning that the clay content in the silt is variable.The piezocone penetration test(CPTu)is the most widely approved in situ test method.It can be used to invert soil properties and interpret soil behavior.To analyse the strength properties of surface sediments in the HRD,this paper evaluated the friction angle and its inversion formula through the CPTu penetration test and monotonic simple shear test and other soil unit experiments.The evaluation showed that the empirical formula proposed by Kulhawy and Mayne had better prediction and inversion effect.The HRD silts with clay contents of 9.2%,21.4%and 30.3%were selected as samples for the CPTu variable rate penetration test.The results show as follows.(1)The effects of the clay content on the tip resistance and the pore pressure of silt under different penetration rates were summarized.The tip resistance Q_t is strongly dependent on the clay content of the silt,the B_(q)value of the silt tends to 0 and is not significantly affected by the change of the CPTu penetration rate.(2)Five soil behavior type classification charts and three soil behavior type indexes based on CPTu data were evaluated.The results show that the soil behavior type classification chart based on soil behavior type index ISBT,the Robertson 2010 behavior type classification chart are more suitable for the silty soil in the HRD. 展开更多
关键词 Huanghe River Delta piezocone penetration test silty soils clay content friction angle soil behaviour type classification
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HY-PC:Enabling Consistent Positioning and Communication Using Visible Light
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作者 Xiangyu Liu Yaoheng Chen +1 位作者 lei guo Song Song 《China Communications》 SCIE CSCD 2023年第4期180-194,共15页
Visible light(VL)plays an important role in achieving high-precision positioning and low bit error radio(BER)data communication.However,most VL-based systems can not achieve positioning and communication,simultaneousl... Visible light(VL)plays an important role in achieving high-precision positioning and low bit error radio(BER)data communication.However,most VL-based systems can not achieve positioning and communication,simultaneously.There are two problems:1)the hybrid systems are difficult to extract distinguishable positioning beacon features without affecting communication performance,2)in the hybrid systems,the lost data bits in the inter-frame gap(IFG)are hard to recover,which affects positioning and communication performance.Therefore,in this article,we propose a novel VL-based hybrid positioning and communication system,named HY-PC system,to solve the above problems.First,we propose the robust T-W mapping for recognizing specific Light Emitting Diodes(LEDs),which can provide stable LED recognition accuracy without adding extra beacon data and does not decrease the communication rate.Furthermore,we also propose the novel linear block coding and bit interleaving mechanism,which can recover the lost data bits in the IFG and improve data communication performance.Finally,we use commercial off-the-shelf devices to implement our HY-PC system,extensive experimental results show that our HY-PC system can achieve consistent high-precision positioning and low-BER data communication,simultaneously. 展开更多
关键词 visible light positioning visible light communication T-W Mapping linear block coding bit interleaving
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Adaptive delay-energy balanced partial offloading strategy in Mobile Edge Computing networks
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作者 Shumei Liu Yao Yu +3 位作者 lei guo Phee Lep Yeoh Branka Vucetic Yonghui Li 《Digital Communications and Networks》 SCIE CSCD 2023年第6期1310-1318,共9页
Mobile Edge Computing(MEC)-based computation offloading is a promising application paradigm for serving large numbers of users with various delay and energy requirements.In this paper,we propose a flexible MECbased re... Mobile Edge Computing(MEC)-based computation offloading is a promising application paradigm for serving large numbers of users with various delay and energy requirements.In this paper,we propose a flexible MECbased requirement-adaptive partial offloading model to accommodate each user's specific preference regarding delay and energy consumption.To address the dimensional differences between time and energy,we introduce two normalized parameters and then derive the computational overhead of processing tasks.Different from existing works,this paper considers practical variations in the user request patterns,and exploits a flexible partial offloading mode to minimize computation overheads subject to tolerable delay,task workload and power constraints.Since the resulting problem is non-convex,we decouple it into two convex subproblems and present an iterative algorithm to obtain a feasible offloading solution.Numerical experiments show that our proposed scheme achieves a significant improvement in computation overheads compared with existing schemes. 展开更多
关键词 Mobile edge computing(MEC) DELAY Energy consumption Dynamic balance Partial computation offloading
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Dynamic Visible Light Positioning Based on Enhanced Visual Target Tracking
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作者 Xiangyu Liu Jingyu Hao +1 位作者 lei guo Song Song 《China Communications》 SCIE CSCD 2023年第10期276-291,共16页
In visible light positioning systems,some scholars have proposed target tracking algorithms to balance the relationship among positioning accuracy,real-time performance,and robustness.However,there are still two probl... In visible light positioning systems,some scholars have proposed target tracking algorithms to balance the relationship among positioning accuracy,real-time performance,and robustness.However,there are still two problems:(1)When the captured LED disappears and the uncertain LED reappears,existing tracking algorithms may recognize the landmark in error;(2)The receiver is not always able to achieve positioning under various moving statuses.In this paper,we propose an enhanced visual target tracking algorithm to solve the above problems.First,we design the lightweight recognition/demodulation mechanism,which combines Kalman filtering with simple image preprocessing to quickly track and accurately demodulate the landmark.Then,we use the Gaussian mixture model and the LED color feature to enable the system to achieve positioning,when the receiver is under various moving statuses.Experimental results show that our system can achieve high-precision dynamic positioning and improve the system’s comprehensive performance. 展开更多
关键词 visible light positioning visual target tracking gaussian mixture model kalman filtering system performance
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Graph CA: Learning From Graph Counterfactual Augmentation for Knowledge Tracing
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作者 Xinhua Wang Shasha Zhao +3 位作者 lei guo lei Zhu Chaoran Cui Liancheng Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2108-2123,共16页
With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery ... With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery of knowledge based on their historical exercise sequences. Nowadays, many related works have emerged in this field, such as Bayesian knowledge tracing and deep knowledge tracing methods. Despite the progress that has been made in KT, existing techniques still have the following limitations: 1) Previous studies address KT by only exploring the observational sparsity data distribution, and the counterfactual data distribution has been largely ignored. 2) Current works designed for KT only consider either the entity relationships between questions and concepts, or the relations between two concepts, and none of them investigates the relations among students, questions, and concepts, simultaneously, leading to inaccurate student modeling. To address the above limitations,we propose a graph counterfactual augmentation method for knowledge tracing. Concretely, to consider the multiple relationships among different entities, we first uniform students, questions, and concepts in graphs, and then leverage a heterogeneous graph convolutional network to conduct representation learning.To model the counterfactual world, we conduct counterfactual transformations on students’ learning graphs by changing the corresponding treatments and then exploit the counterfactual outcomes in a contrastive learning framework. We conduct extensive experiments on three real-world datasets, and the experimental results demonstrate the superiority of our proposed Graph CA method compared with several state-of-the-art baselines. 展开更多
关键词 Contrastive learning counterfactual representation graph neural network knowledge tracing
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Study on Mechanical Properties and Action Mechanism of Leather Industrial Sludge Aggregate Baking-Free Bricks
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作者 lei guo Zekun Wang +1 位作者 Lixia guo Pingping Chen 《Journal of Renewable Materials》 SCIE EI 2023年第1期453-471,共19页
Taking an industrial sludge and its preparation of sludge wrap shell aggregates(WSAs)instead of sand to prepare baking-free brick as the research object,the development law of mechanical properties and the influence m... Taking an industrial sludge and its preparation of sludge wrap shell aggregates(WSAs)instead of sand to prepare baking-free brick as the research object,the development law of mechanical properties and the influence mechanism of macro and micro characteristic parameters of the bricks under different sludge and WSAs replacement rates were studied through the macroscopic mechanical properties test,with the help of nuclear magnetic resonance(NMR),transmission electron microscopy-energy spectrum and other testing technology and pores and cracks analysis system(PCAS)software.The results showed that the compressive strength of each sample decreased with the increase of sludge content.When the sludge content was less than 30%,it was mainly affected by the water-binder ratio.When the sludge content was more than 30%,it was mainly affected by the sludge content.At the age of 7 days,with the increase in replacement rate of WSAs,the compressive strength of the S10 and S30 groups was higher than that of the control group.The compressive strength of the S50 experimental group was 30.38 MPa,and the loss of compressive strength was slight compared with the control group.The water absorption rate of the 28 days S100 experimental group increased by 10.71%compared with the control group.When the content of WSAs was less than 50%,the holes above 0.1μm in the brick can be reduced and transformed into smaller holes,with a decreasing trend of the plane porosity of the brick.The microscopic results of the baking-free brick showed that the three-phase system of WSAs-interface transition area-mortar was poorly bonded and delaminated compared with the gravel aggregate-interface transition area-mortar system,and damage was more likely to occur in the WSAs and interface transition area.The above results show that it is feasible to use sludge and WSAs instead of sand for the preparation of baking-free bricks.This technology not only solves the problem of sludge disposal,but also protects the over-exploitation of mineral resources,and the technology has a broad application prospect and market value. 展开更多
关键词 SLUDGE wrap shell aggregates baking-free brick interface
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Comparison of ethanol-soaked gelatin sponge and microspheres for hepatic arterioportal fistulas embolization in hepatic cellular carcinoma
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作者 Guang-Sheng Yuan Li-Li Zhang +7 位作者 Zi-Tong Chen Cun-Jing Zhang Shu-Hui Tian Ming-Xia Gong Peng Wang lei guo Nan Shao Bin Liu 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第9期1595-1604,共10页
Hepatic arterioportal fistulas(APFs)are common in hepatocellular carcinoma(HCC).Moreover,correlated with poor prognosis,APFs often complicate antitumor treatments,including transarterial chemoembolization(TACE).AIM To... Hepatic arterioportal fistulas(APFs)are common in hepatocellular carcinoma(HCC).Moreover,correlated with poor prognosis,APFs often complicate antitumor treatments,including transarterial chemoembolization(TACE).AIM To compare the efficacy of ethanol-soaked gelatin sponges(ESG)and microspheres in the management of APFs and their impact on the prognosis of HCC.METHODS Data from patients diagnosed with HCC or hepatic APFs between June 2016 and December 2019 were retrospectively analyzed.Furthermore,APFs were embolized with ESG(group E)or microspheres(group M)during TACE.The primary outcomes were disease control rate(DCR)and objective response rate(ORR).The secondary outcomes included immediate and first follow-up APF improvement,overall survival(OS),and progression-free survival(PFS).RESULTS Altogether,91 participants were enrolled in the study,comprising 46 in group E and 45 in group M.The DCR was 93.5%and 91.1%in groups E and M,respectively(P=0.714).The ORRs were 91.3%and 66.7%in groups E and M,respectively(P=0.004).The APFs improved immediately after the procedure in 43(93.5%)patients in group E and 40(88.9%)patients in group M(P=0.485).After 2 mo,APF improvement was achieved in 37(80.4%)and 33(73.3%)participants in groups E and M,respectively(P=0.421).The OS was 26.2±1.4 and 20.6±1.1 mo in groups E and M,respectively(P=0.004),whereas the PFS was 16.6±1.0 and 13.8±0.7 mo in groups E and M,respectively(P=0.012).CONCLUSION Compared with microspheres,ESG embolization demonstrated a higher ORR and longer OS and PFS in patients of HCC with hepatic APFs. 展开更多
关键词 Hepatocellular carcinoma Arterioportal fistula ETHANOL Gelatin sponge MICROSPHERE EMBOLIZATION
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Quantifying the Microeconomic and Macroeconomic Impact of the Recent Crude Oil Price Fluctuations 被引量:1
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作者 Peng Xu Utsav Adhikari +4 位作者 lei guo Deepa Sathaye Jihua Wang Dongliang Yi Yizhi Zhu 《Open Journal of Statistics》 2016年第4期605-615,共11页
This study analyzed the potential impact of the increased oil volatility on the industries and the global economy. Specifically, it separated the oil price fluctuations into positive and negative components, and model... This study analyzed the potential impact of the increased oil volatility on the industries and the global economy. Specifically, it separated the oil price fluctuations into positive and negative components, and modeled the return of industry portfolios with them. Next, the sensitivity of the airline industry to oil price was investigated to gauge the effectiveness of their hedging strategies, with the hope that the methodology can be extended to other industries. In addition, this paper explored the macroeconomic impact of oil price movements by examining the benchmarks such as GDP and CPI. 展开更多
关键词 Crude Oil AIRLINE HEDGING Asymmetric Effects MICROECONOMICS MACROECONOMICS
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Countermeasures to Strengthen Teaching Facilities in the Information Age
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作者 lei guo Xin Wang Youzi Li 《Journal of Electronic Research and Application》 2023年第6期23-29,共7页
Teaching security management is important for institutions to effectively manage teaching resources.This article takes Xi’an Mingde Institute of Technology(referred to as Mingde Institute)as the research subject and ... Teaching security management is important for institutions to effectively manage teaching resources.This article takes Xi’an Mingde Institute of Technology(referred to as Mingde Institute)as the research subject and uses the literature review and field investigation to put forward relevant suggestions for the teaching facilities of Mingde Institute,in order to improve the teaching facilities of Mingde Institute. 展开更多
关键词 INFORMATIZATION Teaching facilities Management measures
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