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石墨烯与六方氮化硼导电性差异的理论研究
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作者 李晓艳 刘晴 +2 位作者 钟雨芙 罗培研 曾艳丽 《大学化学》 CAS 2024年第1期364-368,共5页
石墨烯和六方氮化硼(h-BN)属于等电子体。二者具有类似的结构,但导电性能截然不同。石墨烯具有良好的导电性能,但h-BN是电绝缘体。本文基于量子化学计算,通过自然键轨道分析、电子密度拓扑分析、核独立化学位移(NICS)和磁感应电流密度(A... 石墨烯和六方氮化硼(h-BN)属于等电子体。二者具有类似的结构,但导电性能截然不同。石墨烯具有良好的导电性能,但h-BN是电绝缘体。本文基于量子化学计算,通过自然键轨道分析、电子密度拓扑分析、核独立化学位移(NICS)和磁感应电流密度(AICD)等方法对模型分子C24H12及B12N12H12的电子结构进行了分析,对石墨烯和h-BN导电性差异进行了理论解释。研究结果有助于加深学生对等电子体、定域、离域π键等基本概念的理解。 展开更多
关键词 石墨烯 六方氮化硼 导电性
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新辅助免疫治疗联合化疗与手术治疗局部晚期可切除非小细胞肺癌的短期疗效比较
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作者 李海天 刘晴 +6 位作者 李斌 陈玉珍 蔺军平 孟于琪 冯海明 郑智中 惠一鸣 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第6期421-430,共10页
背景与目的 肺癌是中国发生率和死亡率均排名第一的癌症,非小细胞肺癌(non-small cell lung cancer,NSCLC)占所有肺恶性肿瘤的80%-85%。目前,手术治疗仍是肺癌主要的治疗方式。近年来,免疫检查点抑制剂在NSCLC中的疗效已成为共识,新辅... 背景与目的 肺癌是中国发生率和死亡率均排名第一的癌症,非小细胞肺癌(non-small cell lung cancer,NSCLC)占所有肺恶性肿瘤的80%-85%。目前,手术治疗仍是肺癌主要的治疗方式。近年来,免疫检查点抑制剂在NSCLC中的疗效已成为共识,新辅助免疫联合化疗(neoadjuvant immunochemotherapy, nICT)在早中期NSCLC中显示出来良好的疗效和安全性。然而,nICT治疗局部晚期NSCLC的相关研究较少。本研究旨在评估程序性死亡受体1(programmed cell death 1, PD-1)抑制剂联合含铂两药新辅助治疗治疗局部晚期可切除NSCLC的有效性和安全性。方法 纳入2021年1月至2024年4月于兰州大学第二医院胸外科就诊的85例确诊可切除ⅢA、ⅢB期患者,分为nICT组(n=32)和单纯手术组(n=53),比较两组患者的临床基线资料、围手术期相关指标及术后并发症,并评估n ICT组的影像学缓解率、病理学缓解率、相关不良反应发生率、生活质量。结果 两组患者临床基线资料差异均无统计学意义(P>0.05)。nICT组选择开胸方式比单纯手术组发生率高(P=0.002),两组手术时间、术中出血量、清扫淋巴结个数、带管时间、术后住院时间及R0切除率的差异无统计学意义(P>0.05)。nICT组与单纯手术组术后总并发症发生率分别为31.25%和22.64%,差异无统计学意义(P=0.380)。nICT组中客观缓解率(objective responserate,ORR)为84.38%,完全缓解(completeresponse,CR)5例(15.63%),部分缓解(partialresponse,PR)22例(68.75%),病理性完全缓解(pathologicalcompleteresponse,pCR)15例(46.88%),主要病理缓解(major pathologicalreaponse,MPR)11例(34.38%)。nICT治疗期间,3级治疗相关不良反应共12例(37.50%),无不良反应或免疫相关不良反应导致患者死亡。而且,n ICT治疗后患者相关症状有所改善。结论 nICT治疗局部晚期可切除NSCLC显示出良好的疗效,治疗相关不良事件可控,是局部晚期可切除NSCLC安全、可行的新辅助治疗模式。 展开更多
关键词 肺肿瘤 新辅助免疫化疗 PD-1抑制剂 客观缓解率 并发症
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地基非均匀沉降下天然气管道应力分析 被引量:1
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作者 刘庆 谢荣勃 +3 位作者 鱼东溟 车馨心 闫渊 吴峰 《石化技术》 CAS 2024年第1期172-177,共6页
湿陷性黄土在受水浸湿后产生了严重的地基非均匀沉降现象,对管道产生了附加应力,产生了肉眼可见的位移偏量,严重影响天然气管道的运输安全。针对志丹压气站天然气输气管道的复杂铺设结构进行了应力计算与分析,结合现场监测数据与数值模... 湿陷性黄土在受水浸湿后产生了严重的地基非均匀沉降现象,对管道产生了附加应力,产生了肉眼可见的位移偏量,严重影响天然气管道的运输安全。针对志丹压气站天然气输气管道的复杂铺设结构进行了应力计算与分析,结合现场监测数据与数值模拟分析,给出关键点的应力和位移,验证了模型合理性,对输气管道应力状态进行预测分析,得到了对工程设计与改进具有重要意义的结论,为天然气管道的应力预测提供了理论依据。 展开更多
关键词 地基非均匀沉降 天然气管道 数值模拟 应力分析
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调控N中间体与一维共轭配位聚合物的相互作用促进电催化硝酸盐还原产氨
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作者 刘青 成雪峰 +5 位作者 霍锦艳 刘小芳 董慧龙 曾宏波 徐庆锋 路建美 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第7期231-242,共12页
随着工农业的快速发展及城市化进程的加速,含硝酸盐废水的处理问题日益突出,对生态环境与人类健康造成了严重的威胁.电催化硝酸盐还原制备氨是一种在温和条件下去除硝酸盐污染物并生成氨的可行策略,兼具环境与经济双重价值.然而,由于硝... 随着工农业的快速发展及城市化进程的加速,含硝酸盐废水的处理问题日益突出,对生态环境与人类健康造成了严重的威胁.电催化硝酸盐还原制备氨是一种在温和条件下去除硝酸盐污染物并生成氨的可行策略,兼具环境与经济双重价值.然而,由于硝酸盐还原制氨过程涉及复杂的电子质子转移过程,在低浓度(≤100 ppm)硝酸盐条件下,硝酸盐转化率低和氨产率不足严重制约了该技术的工业应用和发展潜力.因此,开发新型的可精准调控催化中心结构的催化剂材料,并通过调控催化剂表面对含N中间体的吸附来提高硝酸盐的转化率和氨的产率,对于解决上述问题具有重要意义.本文通过过渡金属离子M^(2+)(M=Fe,Co,Ni和Cu)与1,2,4,5-苯四胺(BTA)配体配位合成了四种一维共轭配位聚合物链(1D CCPs)材料,并将其应用于电催化硝酸盐还原制备高附加值产物氨.通过改变金属离子,电催化硝酸盐还原的选择性和活性得到了提高,这些1D CCPs结构为探索电催化硝酸盐还原制氨中的结构-活性关系提供了良好的平台.反应2 h后,Cu-BTA的产氨速率达到2.28 mg h^(-1)c^(-2),该结果是已报道的低浓度硝酸盐还原产氨的较高水平,在4h内硝酸盐的转化率达到96.74%,氨的选择性为79.46%.在经过25次循环实验后,催化性能依然保持良好.密度泛函理论计算结果表明,富电子Cu中心减弱了*NO中间体π轨道向Cu的d轨道的电子转移效率,并增强了Cu d_(yz)轨道对*NO的π轨道的电子反馈作用,提升了*NO中间体的自由能,N=O键被削弱,降低了NO→*NHO的ΔG值,进一步促进了氢化反应,提高了产氨速率.此外,Cu-BTA对氨的吸附能最小,有利于活性中心表面产生的氨快速脱除,加快了吸附-催化转化-脱附循环的速率,并且降低了催化中心中毒的可能性,从而实现了高催化活性和长期稳定性.综上,由于电催化硝酸盐还原制氨过程涉及八电子九质子转移过程,因此催化剂对不同含N中间体的适度吸附能力对保证高选择性,至关重要.本研究通过中心金属离子替换调控对N中间体的吸附,构建了可靠的电催化硝酸盐还原制氨的结构-活性关系,为电催化硝酸盐转化提供了新见解. 展开更多
关键词 硝酸盐还原 氨合成 电催化 一维共轭配位聚合物 吸附调控
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有机化学基础实验室精细化管理的探索与实践
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作者 廖梦尘 阳华 +4 位作者 刘又年 何震 张茂林 刘清 丁激文 《大学化学》 CAS 2024年第10期164-173,共10页
本文从中南大学有机化学基础实验室日常教学管理工作实际出发,介绍了一系列精细化管理改革措施与实施细则。通过引入药品动态数字化出入库、仪器定点分区化摆设、危险废弃物流程化处理的管理模式,为师生打造规范、安全、整洁、方便的实... 本文从中南大学有机化学基础实验室日常教学管理工作实际出发,介绍了一系列精细化管理改革措施与实施细则。通过引入药品动态数字化出入库、仪器定点分区化摆设、危险废弃物流程化处理的管理模式,为师生打造规范、安全、整洁、方便的实验教学环境。同时,本文创新性提出“玻璃仪器认领处”与“自我检查、‘排长’复查、实验教师三查”的实验室管理制度,借以充分调动学生主动性与积极性,培养学生的“主人翁”意识。从而实现有机化学基础实验室整体管理水平和教学效率的提升。 展开更多
关键词 有机化学实验 实验室管理 精细化管理 改革措施
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NaHCO_(3)溶液浓度改变引起的支配质子转移反应变化:从HCO_(3)^(-)质子自递反应到HCO_(3)^(-)水解反应
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作者 柳青 刘建宇 王海水 《大学化学》 CAS 2024年第1期305-308,共4页
NaHCO_(3)水溶液中存在多个质子转移反应和多重化学平衡。随溶液浓度改变,各质子反应所占的相对比重将发生变化,与质子转移相关的产物H_(2)CO_(3)、H^(+)、OH^(-)和CO_(3)^(2-)的相对含量也会发生变化。绘制了[H_(2)CO_(3)]、[H^(+)]、[... NaHCO_(3)水溶液中存在多个质子转移反应和多重化学平衡。随溶液浓度改变,各质子反应所占的相对比重将发生变化,与质子转移相关的产物H_(2)CO_(3)、H^(+)、OH^(-)和CO_(3)^(2-)的相对含量也会发生变化。绘制了[H_(2)CO_(3)]、[H^(+)]、[OH^(-)]和[CO_(3)^(2-)]随溶液浓度c变化的动态图。从动态图上,可以直观地观察到哪些酸碱组分是主要组分,哪些组分是次要组分。较浓溶液中,[H_(2)CO_(3)]≈[CO_(3)^(2-)]>>[OH^(-)]>>[H^(+)],表明能够产生H^(+)或OH^(-)的质子反应占据次要地位,质子反应HCO_(3)^(-)+HCO_(3)^(-)-H_(2)CO_(3)+CO_(3)^(2-)占据支配地位。9.1×10^(-6) mol-L^(-1)溶液中,[OH^(-)]≈[H_(2)CO_(3)]>>[H^(+)]≈[CO_(3)^(2-)],表明质子反应H_(2)O+HCO_(3)^(-)-H_(2)CO_(3)+OH^(-)占据支配地位。极稀溶液中,[OH^(-)]≈[H^(+)]>>[H_(2)CO_(3)]>[CO_(3)^(2-)],表明H_(2)O-H^(+)+OH^(-)占据支配地位。溶液的酸碱性质主要由起支配作用的质子转移反应控制。 展开更多
关键词 碳酸氢钠溶液 多重平衡 支配反应 反应产物含量图
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Effects of hormone replacement therapy on mood and sleep quality in menopausal women 被引量:2
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作者 qing liu Zhen Huang Ping Xu 《World Journal of Psychiatry》 SCIE 2024年第7期1087-1094,共8页
BACKGROUND Hormone replacement therapy is an effective treatment strategy for the management of symptoms in naturally menopausal women.However,some patients report experiencing adverse effects.AIM To analyze the effec... BACKGROUND Hormone replacement therapy is an effective treatment strategy for the management of symptoms in naturally menopausal women.However,some patients report experiencing adverse effects.AIM To analyze the effects of hormone replacement therapy in menopausal female patients.METHODS A total of 152 menopausal female patients admitted to the Gynecology Department of the Ganzhou Maternal and Child Health Hospital between January 2021 and December 2023 were divided into the observation group(n=76,conventional treatment+hormone replacement therapy)and the control group(n=76,conventional treatment only)via random casting.The improvement observed in the following items were compared between the groups:Kupperman menopausal index(KMI),emotional state[The Positive and Negative Affect Scale(PANAS)],sleep quality[Self-Rating Scale of Sleep(SRSS)],treatment effectiveness,and treatment safety.RESULTS The modified KMI and SRSS scores of the observation group were lower than those of the control group after three rounds of treatment.The improvement in the PANAS score observed in the observation group was greater than that observed in the control group(P<0.05).The total treatment effectivity rate in the observation group was higher than that in the control group(86.84%vs 96.05%,χ2=4.121,P=0.042).The incidence rate of adverse reactions in the two groups was comparable(6.58%vs 9.21%,χ2=0.361,P=0.547).CONCLUSION Hormone replacement therapy effectively improved the clinical symptoms,actively channeled negative emotions,and improved the quality of sleep in menopausal patients,indicating its effectiveness and safety. 展开更多
关键词 Hormone replacement therapy MENOPAUSE WOMEN Mood states Sleep quality Sex hormones
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Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network 被引量:1
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作者 Xin Shao qing liu +3 位作者 Zicheng Xin Jiangshan Zhang Tao Zhou Shaoshuai Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期106-117,共12页
The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based ... The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter. 展开更多
关键词 basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model
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Revealing the role of pyramidal slip in the high ductility of Mg-Li alloy 被引量:1
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作者 Jing Xu Bo Guan +3 位作者 Yunchang Xin Guangjie Huang Peidong Wu qing liu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1021-1025,共5页
The high ductility of Mg-Li alloy has been mainly ascribed to a high activity of pyramidal<c+a>slip to accommodate plastic strain.In the present study,however,a quantitative analysis reveals that Li-addition can... The high ductility of Mg-Li alloy has been mainly ascribed to a high activity of pyramidal<c+a>slip to accommodate plastic strain.In the present study,however,a quantitative analysis reveals that Li-addition can only slightly stimulate the activation of pyramidal<c+a>slip under compression along the normal direction of a hot-rolled Mg-4.5 wt.%Li plate,with a relative activity of approximately 18%.Although the limited activity of pyramidal<c+a>slip alone cannot accommodate a large plastic strain,it effectively reduces the number of{10.11}−{10.12}double twins,which are believed to be favorable sites for crack initiation.The evidently reduced activity of double twins leads to a lower cracking tendency,and therefore improves ductility. 展开更多
关键词 Mg alloy Plasticity Plastic deformation SLIP Twinning.
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Explainable machine learning model for predicting molten steel temperature in the LF refining process
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作者 Zicheng Xin Jiangshan Zhang +5 位作者 Kaixiang Peng Junguo Zhang Chunhui Zhang Jun Wu Bo Zhang qing liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2657-2669,共13页
Accurate prediction of molten steel temperature in the ladle furnace(LF)refining process has an important influence on the quality of molten steel and the control of steelmaking cost.Extensive research on establishing... Accurate prediction of molten steel temperature in the ladle furnace(LF)refining process has an important influence on the quality of molten steel and the control of steelmaking cost.Extensive research on establishing models to predict molten steel temperature has been conducted.However,most researchers focus solely on improving the accuracy of the model,neglecting its explainability.The present study aims to develop a high-precision and explainable model with improved reliability and transparency.The eXtreme gradient boosting(XGBoost)and light gradient boosting machine(LGBM)were utilized,along with bayesian optimization and grey wolf optimiz-ation(GWO),to establish the prediction model.Different performance evaluation metrics and graphical representations were applied to compare the optimal XGBoost and LGBM models obtained through varying hyperparameter optimization methods with the other models.The findings indicated that the GWO-LGBM model outperformed other methods in predicting molten steel temperature,with a high pre-diction accuracy of 89.35%within the error range of±5°C.The model’s learning/decision process was revealed,and the influence degree of different variables on the molten steel temperature was clarified using the tree structure visualization and SHapley Additive exPlana-tions(SHAP)analysis.Consequently,the explainability of the optimal GWO-LGBM model was enhanced,providing reliable support for prediction results. 展开更多
关键词 ladle furnace refining molten steel temperature eXtreme gradient boosting light gradient boosting machine grey wolf op-timization SHapley Additive exPlanation
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New insights into developmental biology of Eimeria tenella revealed by comparative analysis of mRNA N6-methyladenosine modification between unsporulated oocysts and sporulated oocysts
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作者 qing liu Bingjin Mu +7 位作者 Yijing Meng Linmei Yu Zirui Wang Tao Jia Wenbin Zheng Wenwei Gao Shichen Xie Xingquan Zhu 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期239-250,共12页
Evidence showed that N6-methyladenosine(m^(6)A)modification plays a pivotal role in influencing RNA fate and is strongly associated with cell growth and developmental processes in many species.However,no information r... Evidence showed that N6-methyladenosine(m^(6)A)modification plays a pivotal role in influencing RNA fate and is strongly associated with cell growth and developmental processes in many species.However,no information regarding m^(6)A modification in Eimeria tenella is currently available.In the present study,we surveyed the transcriptome-wide prevalence of m^(6)A in sporulated oocysts and unsporulated oocysts of E.tenella.Methylated RNA immunoprecipitation sequencing(MeRIP-seq)analysis showed that m^(6)A modification was most abundant in the coding sequences,followed by stop codon.There were 3,903 hypermethylated and 3,178 hypomethylated mRNAs in sporulated oocysts compared with unsporulated oocysts.Further joint analysis suggested that m^(6)A modification of the majority of genes was positively correlated with mRNA expression.The mRNA relative expression and m^(6)A level of the selected genes were confirmed by quantitative reverse transcription PCR(RT-qPCR)and MeRIP-qPCR.GO and KEGG analysis indicated that differentially m^(6)A methylated genes(DMMGs)with significant differences in mRNA expression were closely related to processes such as regulation of gene expression,epigenetic,microtubule,autophagy-other and TOR signaling.Moreover,a total of 96 DMMGs without significant differences in mRNA expression showed significant differences at protein level.GO and pathway enrichment analysis of the 96 genes showed that RNA methylation may be involved in cell biosynthesis and metabolism of E.tenella.We firstly present a map of RNA m^(6)A modification in E.tenella,which provides significant insights into developmental biology of E.tenella. 展开更多
关键词 Eimeria tenella m^(6)A RNA methylation MeRIP-seq RNA-SEQ proteomic analysis
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Adjuvant postbiotic administration improves dental caries prognosis by restoring the oral microbiota
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作者 qing liu Teng Ma +7 位作者 Cuijiao Feng Yalin Li Hao Jin Xuan Shi Lai-Yu Kwok Yan Shi Tingtao Chen Heping Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2690-2702,共13页
Conventional filling therapy fails to fundamentally reduce oral cariogenic bacteria.Thus,oral microbiota follow-up intervention after filling would be necessary for improving dental caries prognosis.We recruited 9 car... Conventional filling therapy fails to fundamentally reduce oral cariogenic bacteria.Thus,oral microbiota follow-up intervention after filling would be necessary for improving dental caries prognosis.We recruited 9 caries-free individuals,and 89 dental caries subjects(5 dropouts).Eighty-nine patients were randomized into three groups:caries(n=8;no treatment),control(n=40;filling),and postbiotics(n=41;filling and 14-day Probio-Eco®intervention).Salivary samples were collected at 0 day(after filling)and 14 days.Our results showed that the diversity of dental caries oral microbiota was significantly increased compared with healthy subjects,and filling could restore a healthier oral microbiota partially and temporarily.Thepostbiotics intervention keeps a low alpha-diversity.Co-occurrence network analysis showed that a more stable oral microbiota structure after postbiotics intervention.Taxonomic and functional annotation of the microbiota revealed that postbiotics co-treatment significantly:increased the relative abundance of Pseudomonas and P.reactans,decreased the relative abundance of Prevotella shahii,and enriched the energy metabolism-related pathways.BugBase-predicted phenotypes inferred to an oral microbiota with decreased potential pathogenic bacteria and increased oxidative stress-tolerant bacteria after postbiotics intervention.Collectively,it suggested that postbiotics co-treatment could be a promising strategy that restores the oral microecological balance for dental caries. 展开更多
关键词 Postbiotics Oral microbiota Salivary microbiota Dental caries Pacific Biosciences(PacBio)single molecule real-time(SMRT)sequencing Dental filling
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Effects of dense planting patterns on photosynthetic traits of different vertical layers and yield of wheat under different nitrogen rates
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作者 Cuicun Wang Ke Zhang +9 位作者 qing liu Xiufeng Zhang Zhikuan Shi Xue Wang Caili Guo Qiang Cao Yongchao Tian Yan Zhu Xiaojun liu Weixing Cao 《The Crop Journal》 SCIE CSCD 2024年第2期594-604,共11页
A two-year field experiment was conducted to measure the effects of densification methods on photosynthesis and yield of densely planted wheat.Inter-plant and inter-row distances were used to define ratefixed pattern(... A two-year field experiment was conducted to measure the effects of densification methods on photosynthesis and yield of densely planted wheat.Inter-plant and inter-row distances were used to define ratefixed pattern(RR)and row-fixed pattern(RS)density treatments.Meanwhile,four nitrogen(N)rates(0,144,192,and 240 kg N ha-1,termed N0,N144,N192,and N240)were applied with three densities(225,292.5,and 360×10^(4)plants ha^(-1),termed D225,D292.5,and D360).The wheat canopy was clipped into three equal vertical layers(top,middle,and bottom layers),and their chlorophyll density(Ch D)and photosynthetically active radiation interception(FIPAR)were measured.Results showed that the response of Ch D and FIPAR to N rate,density,and pattern varied with different layers.N rate,density,and pattern had significant interaction effects on Ch D.The maximum values of whole-canopy Ch D in the two seasons appeared in N240 combined with D292.5 and D360 under RR,respectively.Across two growing seasons,FIPAR values of RR were higher than those of RS by 29.37%for the top layer and 5.68%for the middle layer,while lower than those of RS by 20.62%for the bottom layer on average.With a low N supply(N0),grain yield was not significantly affected by density for both patterns.At N240,increasing density significantly increased yield under RR,but D360 of RS significantly decreased yield by 3.72%and 9.00%versus D225 in two seasons,respectively.With an appropriate and sufficient N application,RR increased the yield of densely planted wheat more than RS.Additionally,the maximum yield in two seasons appeared in the combination of D360 with N144 or N192 rather than of D225 with N240 under both patterns,suggesting that dense planting combined with an appropriate N-reduction application is feasible to increase photosynthesis capacity and yield. 展开更多
关键词 Chlorophyll density Densification method Nitrogen Photosynthetically active radiation INTERCEPTION WHEAT
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Relationship between hydrogenation degree and pyrolysis performance of jet fuel
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作者 qing liu Tinghao Jia +2 位作者 Lun Pan Jijun Zou Xiangwen Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期35-42,共8页
Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel(EHF) is of great significance for the design and optimization of advanced EHFs. In this work, t... Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel(EHF) is of great significance for the design and optimization of advanced EHFs. In this work, the effect of deep hydrogenation on the pyrolysis of commercial RP-3 is investigated.Fuels with different hydrogenation degrees were obtained by the partially and completely catalytic hydrogenation and their pyrolysis performances were investigated using an apparatus equipped with an electrically heated tubular reactor. The results show that with the increase of hydrogenation degree, fuel conversion almost remains constant during the pyrolysis process(500-650°C, 4 MPa);however, the heat sink increases slightly, and the anti-coking performance significantly improves, which are highly related to their H/C ratios. Detailed characterisations reveal that the difference of the pyrolysis performance can be ascribed to the content of aromatics and cycloalkanes: the former are prone to initiate secondary reactions to form coking precursors, while the latter could act as the hydrogen donor and release hydrogen, which will terminate the radical propagation reactions and suppress the coke deposition. This work should provide the guidance for upgrading EHFs by modulating the composition of EHFs. 展开更多
关键词 RP-3 FUEL PYROLYSIS HYDROGENATION DEPOSITION
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A 48-bp deletion upstream of LIGULELESS 1 alters rice panicle architecture
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作者 Linhua Wu Min Hu +6 位作者 Shuwei Lyu Wenfeng Chen Hang Yu qing liu Wei He Chen Li Zuofeng Zhu 《The Crop Journal》 SCIE CSCD 2024年第2期354-363,共10页
Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANIC... Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANICLE 1(OP1),a gain-of-function allele of LIGULELESS 1(LG1),controlling the spread-panicle phenotype.This allele results from a 48-bp deletion in the LG1 upstream region and promotes pulvinus development at the base of the primary branch.Increased OP1 expression and altered panicle phenotype in chimeric transgenic plants and upstream-region knockout mutants indicated that the deletion regulates spread-panicle architecture in the mutant spread panicle 1(sp1).Knocking out BRASSINOSTEROID UPREGULATED1(BU1)gene in the background of OP1 complementary plants resulted in compact panicles,suggesting OP1 may regulate inflorescence architecture via the brassinosteroid signaling pathway.We regard that manipulating the upstream regulatory region of OP1 or genes involved in BR signal pathway could be an efficient way to improve rice inflorescence architecture. 展开更多
关键词 Upstream region Panicle architecture Gene expression BR Rice
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Neuromorphic circuits based on memristors: endowing robots with a human-like brain
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作者 Xuemei Wang Fan Yang +7 位作者 qing liu Zien Zhang Zhixing Wen Jiangang Chen Qirui Zhang Cheng Wang Ge Wang Fucai liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期47-63,共17页
Robots are widely used,providing significant convenience in daily life and production.With the rapid development of artificial intelligence and neuromorphic computing in recent years,the realization of more intelligen... Robots are widely used,providing significant convenience in daily life and production.With the rapid development of artificial intelligence and neuromorphic computing in recent years,the realization of more intelligent robots through a pro-found intersection of neuroscience and robotics has received much attention.Neuromorphic circuits based on memristors used to construct hardware neural networks have proved to be a promising solution of shattering traditional control limita-tions in the field of robot control,showcasing characteristics that enhance robot intelligence,speed,and energy efficiency.Start-ing with introducing the working mechanism of memristors and peripheral circuit design,this review gives a comprehensive analysis on the biomimetic information processing and biomimetic driving operations achieved through the utilization of neuro-morphic circuits in brain-like control.Four hardware neural network approaches,including digital-analog hybrid circuit design,novel device structure design,multi-regulation mechanism,and crossbar array,are summarized,which can well simulate the motor decision-making mechanism,multi-information integration and parallel control of brain at the hardware level.It will be definitely conductive to promote the application of memristor-based neuromorphic circuits in areas such as intelligent robotics,artificial intelligence,and neural computing.Finally,a conclusion and future prospects are discussed. 展开更多
关键词 neuromorphic devices neuromorphic circuits hardware networks MEMRISTORS humanlike robots
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The UDP-glycosyltransferase OsUGT706D2 positively regulates cold and submergence stress tolerance in rice
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作者 qing liu Lanlan Zhang +12 位作者 Shuwei Lyu Hang Yu Wenjie Huang Liqun Jiang Jing Zhang Bingrui Sun Xingxue Mao Pingli Chen Junlian Xing Wenfeng Chen Zhilan Fan Shijuan Yan Chen Li 《The Crop Journal》 SCIE CSCD 2024年第3期732-742,共11页
In a genome-wide association study,we identified a rice UDP-glycosyltransferase gene,OsUGT706D2,whose transcription was activated in response to cold and submergence stress and to exogenous abscisic acid(ABA).OsUGT706... In a genome-wide association study,we identified a rice UDP-glycosyltransferase gene,OsUGT706D2,whose transcription was activated in response to cold and submergence stress and to exogenous abscisic acid(ABA).OsUGT706D2 positively regulated the biosynthesis of tricin-4’-O-(syringyl alcohol)ether-7-O-glucoside at both the transcriptional and metabolic levels.OsUGT706D2 mediated cold and submergence tolerance by modulating the expression of stress-responsive genes as well as the abscisic acid(ABA)signaling pathway.Gain of function of OsUGT706D2 increased cold and submergence tolerance and loss of function of OsUGT706D2 reduced cold tolerance.ABA positively regulated OsUGT706D2-mediated cold tolerance but reduced submergence tolerance.These findings suggest the potential use of OsUGT706D2 for improving abiotic stress tolerance in rice. 展开更多
关键词 UDP-glycosyltransferase RICE Cold tolerance Submergence tolerance ABA
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Introgression of lac6/tl1/du13 improves the palatability of japonica rice
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作者 Yong Yang Tao Zhang +9 位作者 Yuliang Shi Yan Lu Qianfeng Li Xiaolei Fan Lichun Huang Lu Chen Xuetang Song qing liu Changquan Zhang Qiaoquan liu 《The Crop Journal》 SCIE CSCD 2024年第4期1259-1265,共7页
Amylose content(AC)is a crucial determinant of the eating and cooking quality(ECQ)of rice,with low AC varieties exhibiting a softer texture and greater stickiness-attributes that enhance palatability and are desirable... Amylose content(AC)is a crucial determinant of the eating and cooking quality(ECQ)of rice,with low AC varieties exhibiting a softer texture and greater stickiness-attributes that enhance palatability and are desirable in specific culinary contexts.To harness these traits,significant efforts have been made to manipulate AC to improve rice ECQ.Our research utilized the MutMap+approach to identify LAC6/TL1,a gene that is an allele of Du13,responsible for low AC.LAC6 encodes a C2H2 zinc finger protein,which specifically increases the splicing efficiency of the Wxb allele without affecting the Wxa allele.Functional studies of LAC6 revealed that its proper integration could rectify the undesirable AC phenotype,whereas mutations within this gene led to reduced AC and were associated with shorter grain length and decreased thousand-grain weight.Despite these drawbacks,such mutations positively impact rice palatability,presenting a trade-off between grain size and eating quality.To address the challenges posed by the reduced grain weight associated with LAC6 mutations,we developed a specific molecular marker for LAC6,which has been effectively used in breeding programs to select lac6/tl1/du13 homozygous individuals with larger grain size.Our findings demonstrate that the“small grain”trait associated with lac6/tl1/du13 can be effectively mitigated through combined phenotype-based and marker-assisted selection.This study highlights the potential of lac6/tl1/du13 as a valuable gene for breeding novel,high-quality soft rice varieties through targeted breeding strategies. 展开更多
关键词 Rice Dull endosperm Amylose content WX BREEDING
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Mechanism of action of cordycepin in the treatment of hepatocellular carcinoma via regulation of the Hippo signaling pathway
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作者 Xiaomin Li qing liu +2 位作者 Songyu Xie Xiaoping Wu Junsheng Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1040-1054,共15页
Hepatocellular carcinoma(HCC)is one of the common most malignant tumors.This study aimed to determine the in vitro and in vivo anticancer activity of cordycepin and elucidate its mechanism of action.The results of in ... Hepatocellular carcinoma(HCC)is one of the common most malignant tumors.This study aimed to determine the in vitro and in vivo anticancer activity of cordycepin and elucidate its mechanism of action.The results of in vitro and in vivo studies revealed that cordycepin inhibited proliferation and migration in HepG-2 cells and inhibited the growth of HepG-2 xenograft-bearing nude mice by inducing apoptosis.Transcriptome sequencing analysis revealed a total of 403 differential genes,which revealed that cordycepin may play an anti-HCC role by regulating Hippo signaling pathway.The regulatory effects of cordycepin on the Hippo signaling pathway was further investigated using a YAP1 inhibitor.The results demonstrated that cordycepin upregulated the expression of MST1 and LAST1,and subsequently inhibited YAP1,which activated the Hippo signaling pathway.This in turn downregulated the expression of GBP3 and ETV5,and subsequently inhibited cell proliferation and migration.Additionally,YAP1 regulated the expression of Bax and Bcl-2,regulated the mitochondrial apoptotic pathway,and induced apoptosis by upregulating the expression of the caspase-3 protein.In summary,this study reveals that cordycepin exerts its anti-hepatocarcinoma effect through regulating Hippo signaling pathway,and GBP3 and ETV5 may be potential therapeutic targets for hepatocarcinoma. 展开更多
关键词 CORDYCEPIN Hepatocellular carcinoma Hippo signaling pathway GBP3 ETV5
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A contradictory phenomenon of thicken pericardium and cardiac compression without inferior vena cava dilation:sign of IVC escape
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作者 Tie-Nan CHEN Shuang ZHAO +6 位作者 Shuai QIAO Yong-Yong HAN qing liu Chang-Le liu Guang-Ping LI Tong liu Hua-Ying FU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第5期583-587,共5页
A 77-year-old female presented with shortness of breath and tightness of chest was admitted.Her past medical history included hypertension and she has been taking nifedipine regularly.Two years before,she was diagnose... A 77-year-old female presented with shortness of breath and tightness of chest was admitted.Her past medical history included hypertension and she has been taking nifedipine regularly.Two years before,she was diagnosed with pericardial effusion(Figure 1)and had pericardiocentesis drainage.On physical examination,her blood pressure was 151/100 mm-Hg and her pulse rate was 91 beats/min. 展开更多
关键词 admitted CARDIAC thick
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