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前列地尔注射液结合肠内营养支持在冠心病伴营养不良中应用
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作者 张帆 黄龙武 李雷 《世界华人消化杂志》 CAS 2024年第9期671-677,共7页
背景前列地尔注射液具有抑制血小板聚集、扩张冠状动脉、改善血液循环等作用,肠内营养支持可改善机体营养状态,提高机体免疫力,二者联合应用可能对高龄冠心病伴营养不良治疗效果更佳.目的探讨前列地尔注射液结合肠内营养支持对高龄冠心... 背景前列地尔注射液具有抑制血小板聚集、扩张冠状动脉、改善血液循环等作用,肠内营养支持可改善机体营养状态,提高机体免疫力,二者联合应用可能对高龄冠心病伴营养不良治疗效果更佳.目的探讨前列地尔注射液结合肠内营养支持对高龄冠心病伴营养不良中应用.方法选取2020-02/2022-02我院142例冠心病伴营养不良患者,随机数字表法分组,各71例.对照组采取常规治疗,研究组基于对照组采取前列地尔注射液结合肠内营养支持,连续治疗1 mo.统计两组左心室射血分数(left ventricular ejection fraction,LVEF)、心绞痛持续时间、心绞痛发作频率、营养状况指标[白蛋白(albumin,ALB)、转铁蛋白(transferrin,Tf)、简易营养评价表(mini-nutritional assessment,MNA)]、微炎症状态指标[微小核糖核酸-196a(miR-196a)、微小核糖核酸-146a(miR-146a)]、不良反应、主要心血管不良事件(major adverse cardiovascular events,MACE)及中国心血管患者生活质量评定问卷(china questionnaire of quality of life in patients with cardiovascular diseases,CQQC)评分.结果治疗1 mo后研究组LVEF高于对照组,心绞痛持续时间、心绞痛发作频率低于对照组(P<0.05);治疗1 mo后研究组ALB、Tf水平及MNA评分高于对照组,miR-196a、miR-146a水平低于对照组(P<0.05);两组治疗1 mo后不良反应及MACE发生率比较,差异无统计学意义;治疗1 mo后两组CQQC评分高于治疗前(P<0.05).结论前列地尔注射液结合肠内营养支持应用于高龄冠心病伴营养不良患者,有助于减轻微炎症状态,改善营养状况,控制心绞痛发作症状. 展开更多
关键词 高龄 冠心病 营养不良 微炎症状态 肠内营养支持 前列地尔注射液
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温度和疲劳共同作用对溴化丁基橡胶气体阻隔性能的影响
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作者 张帆 张力伟 +1 位作者 熊英 郭少云 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期134-140,共7页
溴化丁基橡胶(BIIR)因其出色的气体阻隔性能成为轮胎内衬层首选材料,但轮胎使用过程中因摩擦生热产生的高温和滚动过程中的屈挠疲劳作用,其性能和使用寿命将会受到很大的影响,因此,探索温度和疲劳作用对BIIR气体阻隔性能的影响具有重要... 溴化丁基橡胶(BIIR)因其出色的气体阻隔性能成为轮胎内衬层首选材料,但轮胎使用过程中因摩擦生热产生的高温和滚动过程中的屈挠疲劳作用,其性能和使用寿命将会受到很大的影响,因此,探索温度和疲劳作用对BIIR气体阻隔性能的影响具有重要意义。文中对比研究了温度和屈挠疲劳单因素作用以及双因素作用下,BIIR气体阻隔性能的变化情况;通过交联密度测试、动态力学热分析及透射电镜等手段,探寻了BIIR在温度和疲劳双因素作用下其分子交联网络和填料分布情况的变化。结果表明,热老化作用使BIIR交联度增加,气体阻隔性能提高;疲劳作用对其气体阻隔性能的影响也较小;但温度和疲劳共同作用下,BIIR在较高温度下形成的交联网络又经屈挠疲劳的作用,更易发生裂解,并带动填料粒子的“移动”,导致了BIIR橡胶气体阻隔性能的大幅降低。 展开更多
关键词 溴化丁基橡胶 热老化 屈挠疲劳 气体阻隔性能
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超大城市中心城区站城融合规划实践——以北京丰台站街区控规为例
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作者 诸嘉巍 张帆 杨贺 《城市设计》 2024年第1期82-91,共10页
近年来,随着区域一体化迈向更高质量发展,我国超大城市铁路枢纽地区站城关系亟待转型重塑。本文通过梳理国内外枢纽站点发展历程,从宏观、微观两个层面分析站城融合影响要素,总结提炼了3类站城融合的空间模式。以北京国土空间详细规划... 近年来,随着区域一体化迈向更高质量发展,我国超大城市铁路枢纽地区站城关系亟待转型重塑。本文通过梳理国内外枢纽站点发展历程,从宏观、微观两个层面分析站城融合影响要素,总结提炼了3类站城融合的空间模式。以北京国土空间详细规划体系为技术骨架,结合北京丰台站街区控规实践案例,着力通过整体结构、交通支撑、功能布局、空间营造4个方面的探讨,建立超大城市中心城区站城融合的规划范式,以期为我国同类型地区的规划建设提供参考。 展开更多
关键词 枢纽地区 站城融合 空间模式 控制性详细规划
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A Review of Anode Materials for Dual‑Ion Batteries
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作者 Hongzheng Wu Shenghao Luo +6 位作者 Hubing Wang Li Li Yaobing fang fan zhang Xuenong Gao Zhengguo zhang Wenhui Yuan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期618-674,共57页
Distinct from"rockingchair"lithium-ion batteries(LIBs),the unique anionic intercalation chemistry on the cathode side of dual-ion batteries(DIBs)endows them with intrinsic advantages of low cost,high voltage... Distinct from"rockingchair"lithium-ion batteries(LIBs),the unique anionic intercalation chemistry on the cathode side of dual-ion batteries(DIBs)endows them with intrinsic advantages of low cost,high voltage,and ecofriendly,which is attracting widespread attention,and is expected to achieve the next generation of large-scale energy storage applications.Although the electrochemical reactions on the anode side of DIBs are similar to that of LIBs,in fact,to match the rapid insertion kinetics of anions on the cathode side and consider the compatibility with electrolyte system which also serves as an active material,the anode materials play a very important role,and there is an urgent demand for rational structural design and performance optimization.A review and summarization of previous studies will facilitate the exploration and optimization of DIBs in the future.Here,we summarize the development process and working mechanism of DIBs and exhaustively categorize the latest research of DIBs anode materials and their applications in different battery systems.Moreover,the structural design,reaction mechanism and electrochemical performance of anode materials are briefly discussed.Finally,the fundamental challenges,potential strategies and perspectives are also put forward.It is hoped that this review could shed some light for researchers to explore more superior anode materials and advanced systems to further promote the development of DIBs. 展开更多
关键词 Dual-ion batteries ANODE Carbonaceous materials Metallic materials Organic materials Optimization strategies
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The energy response of LaBr_(3)(Ce),LaBr_(3)(Ce,Sr),and NaI(Tl)crystals for GECAM
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作者 Pei-Yi Feng Xi-Lei Sun +19 位作者 Zheng-Hua An Yong Deng Cheng-Er Wang Huang Jiang Jun-Jie Li Da-Li zhang Xin-Qiao Li Shao-Lin Xiong Chao Zheng Ke Gong Sheng Yang Xiao-Jing Liu Min Gao Xiang-Yang Wen Ya-Qing liu Yan-Bing Xu Xiao-Yun Zhao Jia-Cong Liu fan zhang Hong Lu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期110-122,共13页
The GECAM series of satellites utilizes LaBr_(3)(Ce),LaBr_(3)(Ce,Sr),and NaI(Tl)crystals as sensitive materials for gamma-ray detectors(GRDs).To investigate the nonlinearity in the detection of low-energy gamma rays a... The GECAM series of satellites utilizes LaBr_(3)(Ce),LaBr_(3)(Ce,Sr),and NaI(Tl)crystals as sensitive materials for gamma-ray detectors(GRDs).To investigate the nonlinearity in the detection of low-energy gamma rays and address the errors in the calibration of the E-C relationship,comprehensive tests and comparative studies of the three aforementioned crystals were conducted using Compton electrons,radioactive sources,and mono-energetic X-rays.The nonlinearity test results of the Compton electrons and X-rays demonstrated substantial differences,with all three crystals presenting a higher nonlinearity for X/-rays than for Compton electrons.Despite the LaBr_(3)(Ce)and LaBr_(3)(Ce,Sr)crystals having higher absolute light yields,they exhibited a noticeable nonlinear decrease in the light yield,especially at energies below 400 keV.The NaI(Tl)crystal demonstrated an"excess"light output in the 6-200 keV range,reaching a maximum"excess"of 9.2%at 30 keV in the X-ray testing and up to 15.5%at 14 keV during Compton electron testing,indicating a significant advantage in the detection of low-energy gamma rays.Furthermore,we explored the underlying causes of the observed nonlinearity in these crystals.This study not only elucidates the detector responses of GECAM,but also initiates a comprehensive investigation of the nonlinearity of domestically produced lanthanum bromide and sodium iodide crystals. 展开更多
关键词 LaBr_(3)(Ce)detector LaBr_(3)(Ce Sr)detector NaI(Tl)detector GECAM Energy response Light yield nonlinearity
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挤压比对双相Mg-8Li-6Zn-2Gd合金显微组织、织构和力学性能的影响
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作者 孙月花 张帆 +2 位作者 杨滨 任建 宋广生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第3期833-845,共13页
通过显微组织观察、织构分析和拉伸测试等手段研究挤压比对双相Mg-8Li-6Zn-2Gd合金显微组织、织构和力学性能的影响。结果表明:均匀化态Mg-8Li-6Zn-2Gd合金中含有α-Mg、β-Li、Mg Li Zn、I相和W相。经热挤压后,共晶I相被碾碎成细小颗粒... 通过显微组织观察、织构分析和拉伸测试等手段研究挤压比对双相Mg-8Li-6Zn-2Gd合金显微组织、织构和力学性能的影响。结果表明:均匀化态Mg-8Li-6Zn-2Gd合金中含有α-Mg、β-Li、Mg Li Zn、I相和W相。经热挤压后,共晶I相被碾碎成细小颗粒状,而W相保持原有块状形状。合金中α-Mg基体和β-Li基体在热挤压过程中均发生了动态再结晶(DRX),且晶粒随着挤压比的增加逐渐细化。经热挤压后,α-Mg基体的基面织构弱化和柱面织构增强是由于非基面滑移的激活;β-Li基体中形成明显的α和γ纤维织构主要与动态回复与动态再结晶相关。热挤压同时提升Mg-8Li-6Zn-2Gd合金的抗拉强度和伸长率,并在挤压比为16:1时获得最佳的综合力学性能。 展开更多
关键词 MG-LI合金 二十面体准晶相 挤压比 动态再结晶 宏观织构 力学性能
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Artificial selection of the Green Revolution gene Semidwarf 1 is implicated in upland rice breeding
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作者 Shuliang Jiao Qinyan Li +6 位作者 fan zhang Yonghong Tao Yingzhen Yu fan Yao Qingmao Li Fengyi Hu Liyu Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期769-780,共12页
Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a princi... Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a principal role in determining rice plant height. Mutations in SD1 reduce rice plant height and promote lodging resistance and fertilizer tolerance to increase grain production. The plant height mediated by SD1 also favors grain yield under certain conditions. However, it is not yet known whether the function of SD1 in upland rice promotes adaptation and grain production. In this study, the plant height and grain yield of irrigated and upland rice were comparatively analyzed under paddy and dryland conditions. In response to dryland environments, rice requires a reduction in plant height to cope with water deficits. Upland rice accessions had greater plant heights than their irrigated counterparts under both paddy and dryland conditions, and appropriately reducing plant height could improve adaptability to dryland environments and maintain high grain yield formation. Moreover, upland rice cultivars with thicker stem diameters had stronger lodging resistance, which addresses the lodging problem. Knockout of SD1 in the upland rice cultivar IRAT104 reduced the plant height and grain yield, demonstrating that the adjustment of plant height mediated by SD1 could increase grain production in dryland fields. In addition, an SD1 genetic diversity analysis verified that haplotype variation causes phenotypic variation in plant height. During the breeding history of rice, SD1 allelic mutations were selected from landraces to improve the grain yield of irrigated rice cultivars, and this selection was accompanied by a reduction in plant height. Thus, five known mutant alleles were analyzed to verify that functional SD1 is required for upland rice production. All these results suggest that SD1 might have undergone artificial positive selection in upland rice, which provides further insights concerning greater plant height in upland rice breeding. 展开更多
关键词 Green Revolution Semidwarf 1 high-yield breeding upland rice plant height
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Brønsted-acid sites induced photocatalytic cracking of low-polarity polyethylene plastics
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作者 Qianyou Wen Quan zhang +6 位作者 Zhengzheng Liu Huining Wang Shuya Hao fan zhang Lijuan zhang Qing Han Gengfeng Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期509-515,共7页
Polyolefins such as polyethylene(PE)are one of the largest-scale synthetic plastics and play a key role in modern society.However,polyethylene is extremely inert to chemical recycling owing to its lack of chemical fun... Polyolefins such as polyethylene(PE)are one of the largest-scale synthetic plastics and play a key role in modern society.However,polyethylene is extremely inert to chemical recycling owing to its lack of chemical functionality and low polarity,making it one of the most challenging environmental hazards globally.Herein,we developed a phosphorylated CeO_(2)catalyst by an organophosphate precursor and featured efficient photocatalysis of low-density polyethylene(LDPE)without the acid or alkaline pre-treatment.Compared to pristine CeO_(2),the surface phosphorylation allows to introduce Brønsted acid sites,which facilitate to form carbonium ions on LDPE via protonation.In addition,the suitable band structure of the phosphorylated CeO_(2)catalyst enables efficient photoabsorption and generates reactive oxygen species,leading to the C–C bond cleavage of LDPE.As a result,the phosphorylated CeO_(2)catalyst exhibited an outstanding carbon conversion rate of>94%after 48 h of photocatalysis under 50 mW/cm^(2)of simulated sunlight,with a high CO_(2)product selectivity of>99%.Furthermore,the PE microparticles with sizes larger than 10μm released from LDPE plastic wrap were directly and completely degraded by photocatalysis within 12 h,suggesting an attractive and environmentally benign strategy of utilizing solar energy-based photocatalysis for reducing potential hazards of LDPE plastic trashes. 展开更多
关键词 Photocatalytic cracking POLYETHYLENE Surface phosphorylation Bronsted-acid site Carbon conversion
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Antibody-platinum(IV)prodrugs conjugates for targeted treatment of cutaneous squamous cell carcinoma
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作者 Xiangye Yin Yingjie Zhuang +9 位作者 Haiqin Song Yujian Xu fan zhang Jianxin Cui Lei Zhao Yingjie Yu Qixu zhang Jun Ye Youbai Chen Yan Han 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第3期389-400,共12页
Antibody-drug conjugates(ADCs)are a new type of targeting antibodies that conjugate with highly toxic anticancer drugs via chemical linkers to exert high specificity and efficient killing of tumor cells,thereby attrac... Antibody-drug conjugates(ADCs)are a new type of targeting antibodies that conjugate with highly toxic anticancer drugs via chemical linkers to exert high specificity and efficient killing of tumor cells,thereby attracting considerable attention in precise oncology therapy.Cetuximab(Cet)is a typical antibody that offers the benefits of good targeting and safety for individuals with advanced and inoperable cutaneous squamous cell carcinoma(cSCC);however,its anti-tumor activity is limited to a single use.Cisplatin(CisPt)shows good curative effects;however,its adverse effects and non-tumor-targeting ability are major drawbacks.In this study,we designed and developed a new ADC based on a new cytotoxic platinum(IV)prodrug(C8Pt(IV))and Cet.The so-called antibody-platinum(IV)prodrugs conjugates,named Cet-C8Pt(IV),showed excellent tumor targeting in cSCC.Specifically,it accurately delivered C8Pt(IV)into tumor cells to exert the combined anti-tumor effect of Cet and CisPt.Herein,metabolomic analysis showed that Cet-C8Pt(IV)promoted cellular apoptosis and increased DNA damage in cSCC cells by affecting the vitamin B6 metabolic pathway in tumor cells,thereby further enhancing the tumor-killing ability and providing a new strategy for clinical cancer treatment using antibody-platinum(IV)prodrugs conjugates. 展开更多
关键词 Antibody drug conjugate Cutaneous squamous cell carcinoma DNA damage Platinum drug Targeted therapy
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AlLi-LDH中Al-O八面体环吸附锂的机制
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作者 田勇攀 王成成 +3 位作者 张帆 徐亮 赵卓 童碧海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第4期1321-1332,共12页
采用共沉淀法合成铝锂层状双氢氧化物(AlLi-LDH)并进行提锂试验。AlLi-LDH的空间群为P32或C2/m,微观形貌呈直径为5~10μm的规则球形。AlLi-LDH吸附Li^(+)后,空间群转化为P32。当Li^(+)浓度为95.4 mg/L时,1 h后锂吸附量为8.98 mg/g;吸附4... 采用共沉淀法合成铝锂层状双氢氧化物(AlLi-LDH)并进行提锂试验。AlLi-LDH的空间群为P32或C2/m,微观形貌呈直径为5~10μm的规则球形。AlLi-LDH吸附Li^(+)后,空间群转化为P32。当Li^(+)浓度为95.4 mg/L时,1 h后锂吸附量为8.98 mg/g;吸附48 h后,吸附量增加到16.50 mg/g;根据二级吸附模型预测Li^(+)吸附总量为17.57 mg/g。当Mg^(2+)/Li^(+)的质量比为1067时,Mg^(2+)/Li^(+)分离系数为29536。空间群为P32时,Li-O的相互作用强度变弱,且相互作用属于静电效应。具有P32空间基团的AlLi-LDH更容易吸附和解吸Li^(+)。 展开更多
关键词 共沉淀 铝锂层状双氢氧化物 空间群 吸附
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Pachymic acid exerts antitumor activities by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B
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作者 Hao zhang Kun Zhu +5 位作者 Xue-Feng zhang Yi-Hui Ding Bing Zhu Wen Meng Qing-Song Ding fan zhang 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期170-180,共11页
Objective:To determine the inhibitory effects of pachymic acid on lung adenocarcinoma(LUAD)cells and elucidate its underlying mechanism.Methods:CCK-8,wound healing,Transwell,Western blot,tube formation,and immunofluor... Objective:To determine the inhibitory effects of pachymic acid on lung adenocarcinoma(LUAD)cells and elucidate its underlying mechanism.Methods:CCK-8,wound healing,Transwell,Western blot,tube formation,and immunofluorescence assays were carried out to measure the effects of various concentrations of pachymic acid on LUAD cell proliferation,metastasis,angiogenesis as well as autophagy.Subsequently,molecular docking technology was used to detect the potential targeted binding association between pachymic acid and protein tyrosine phosphatase 1B(PTP1B).Moreover,PTP1B was overexpressed in A549 cells to detect the specific mechanisms of pachymic acid.Results:Pachymic acid suppressed LUAD cell viability,metastasis as well as angiogenesis while inducing cell autophagy.It also targeted PTP1B and lowered PTP1B expression.However,PTP1B overexpression reversed the effects of pachymic acid on metastasis,angiogenesis,and autophagy as well as the expression of Wnt3a andβ-catenin in LUAD cells.Conclusions:Pachymic acid inhibits metastasis and angiogenesis,and promotes autophagy in LUAD cells by modulating the Wnt/β-catenin signaling pathway via targeting PTP1B. 展开更多
关键词 Pachymic acid Lung adenocarcinoma Protein tyrosine phosphatase 1B Wnt/β-catenin signaling pathway METASTASIS ANGIOGENESIS AUTOPHAGY
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Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China
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作者 Yan zhang Yi Huang +1 位作者 fan zhang Zeng Tang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1774-1785,共12页
Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.Howeve... Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit. 展开更多
关键词 formal credit herders EXPENSE Qinghai-Xizang Plateau
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非小细胞肺癌免疫检查点抑制剂假性进展的研究进展
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作者 童亚军 龙咏 +1 位作者 张帆 李军烽 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第4期306-320,共15页
免疫检查点抑制剂的出现极大地改善了晚期肺癌患者的预后,但其可能会导致假性进展,使临床评估和管理变得复杂化。假性进展表现为肿瘤暂时性增大或出现新病变等,继续治疗后影像学上出现改善,多不伴有临床症状恶化。目前假性进展在早期诊... 免疫检查点抑制剂的出现极大地改善了晚期肺癌患者的预后,但其可能会导致假性进展,使临床评估和管理变得复杂化。假性进展表现为肿瘤暂时性增大或出现新病变等,继续治疗后影像学上出现改善,多不伴有临床症状恶化。目前假性进展在早期诊断方面仍存在困难,其发生机制尚不明确,缺乏良好的预测因素和相关生物标志物。本文通过对非小细胞肺癌免疫检查点抑制剂假性进展的研究现状进行综述,以期为使用该类药物治疗患者的临床医生提供有益的参考。 展开更多
关键词 肺肿瘤 免疫检查点抑制剂 假性进展 免疫治疗
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Efficient and selective upcycling of waste polylactic acid into acetate using nickel selenide
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作者 Bing Lan Yinfang Chen +4 位作者 Nantian Xiao Na Liu Chao Juan Chuan Xia fan zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期575-584,I0012,共11页
The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts ... The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts for lactic acid oxidation reaction(LAOR)and understanding the reaction process are challenging.Here,we report the electrooxidation of waste PLA to acetate at a high current density of 100 mA cm-2 with high Faraday efficiency(~95%)and excellent stability(>100 h)over a nickel selenide nanosheet catalyst.In addition,a total Faraday efficiency of up to 190%was achieved for carboxylic acids,including acetic acid and formic acid,by coupling with the cathodic CO_(2) reduction reaction.In situ experimental results and theoretical simulations revealed that the catalytic activity center of LAOR was dynamically formed NiOOH species,and the surface-adsorbed SeO_(x) species accelerated the formation of Ni~(3+)species,thus promoting catalytic activity.The mechanism of lactic acid electrooxidation was further elucidated.Lactic acid was dehydrogenated to produce pyruvate first and then formed CH_3CO due to preferential C-C bond cleavage,resulting in the presence of acetate.This work demonstrated a sustainable method for recycling waste PLA and CO_(2) into high-value-added products. 展开更多
关键词 Waste plastic upcycling Poly(lactic acid) Lactic acid electro-oxidation Acetic acid
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Controllable step-flow growth of GaN on patterned freestanding substrate
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作者 Peng Wu Jianping Liu +7 位作者 Lei Hu Xiaoyu Ren Aiqin Tian Wei Zhou fan zhang Xuan Li Masao Ikeda Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第2期46-50,共5页
A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature a... A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature and ammonia flux.The growth mechanism is explained and simulated based on step motion model.This work helps better understand the behaviors of step advancement and puts forward a method of precisely modulating atomic steps. 展开更多
关键词 step-flow growth GAN terrace width step motion
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Electrical properties and structural optimization of GaN/InGaN/GaN tunnel junctions grown by molecular beam epitaxy
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作者 Jun fang fan zhang +4 位作者 Wenxian Yang Aiqin Tian Jianping Liu Shulong Lu Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期48-54,共7页
The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases an... The InGaN films and GaN/InGaN/GaN tunnel junctions(TJs)were grown on GaN templates with plasma-assisted molecular beam epitaxy.As the In content increases,the quality of InGaN films grown on GaN templates decreases and the surface roughness of the samples increases.V-pits and trench defects were not found in the AFM images.p++-GaN/InGaN/n++-GaN TJs were investigated for various In content,InGaN thicknesses and doping concentration in the InGaN insert layer.The InGaN insert layer can promote good interband tunneling in GaN/InGaN/GaN TJ and significantly reduce operating voltage when doping is sufficiently high.The current density increases with increasing In content for the 3 nm InGaN insert layer,which is achieved by reducing the depletion zone width and the height of the potential barrier.At a forward current density of 500 A/cm^(2),the measured voltage was 4.31 V and the differential resistance was measured to be 3.75×10^(−3)Ω·cm^(2)for the device with a 3 nm p++-In_(0.35)Ga_(0.65)N insert layer.When the thickness of the In_(0.35)Ga_(0.65)N layer is closer to the“balanced”thickness,the TJ current density is higher.If the thickness is too high or too low,the width of the depletion zone will increase and the current density will decrease.The undoped InGaN layer has a better performance than n-type doping in the TJ.Polarization-engineered tunnel junctions can enhance the functionality and performance of electronic and optoelectronic devices. 展开更多
关键词 GaN/InGaN/GaN tunnel junctions polarization-engineering molecular beam epitaxy
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Insights into the enhancement of food flavor perception:strategies,mechanism and emulsion applications
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作者 Luyao Huang Yujie Dai +3 位作者 fan zhang Longtao zhang Baodong Zheng Yi zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2410-2424,共15页
The core drivers of the modern food industry are meeting consumer demand for tasty and healthy foods.The application of food flavor perception enhancement can help to achieve the goals of salt-and sugar-reduction,with... The core drivers of the modern food industry are meeting consumer demand for tasty and healthy foods.The application of food flavor perception enhancement can help to achieve the goals of salt-and sugar-reduction,without compromising the sensory quality of the original food,and this has attracted increasing research attention.The analysis of bibliometric results from 2002 to 2022 reveals that present flavor perception enhancement strategies(changing ingredient formulations,adding salt/sugar substitutes,emulsion delivery systems)are mainly carry out based on sweetness,saltiness and umami.Emulsion systems is becoming a novel research foci and development trends of international food flavor perception-enhancement research.The structured design of food emulsions,by using interface engineering technology,can effectively control,or enhance the release of flavor substances.Thus,this review systematically summarizes strategies,the application of emulsion systems and the mechanisms of action of food flavor perception-enhancement technologies,based on odor-taste cross-modal interaction(OTCMI),to provide insights into the further structural design and application of emulsion systems in this field. 展开更多
关键词 Food flavor perception EMULSION MECHANISM BIBLIOMETRIC
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Direct observation of shock-induced phase transformation in polycrystalline iron via in situ x-ray diffraction
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作者 fan zhang Jia-Qin Dong +11 位作者 Zhi-Yong Xie Zhi-Yu He Hua Shu Rui-Rong Wang Jun Xiong Guo Jia Zhi-Heng fang Wei Wang Da-Wu Xiao An-Le Lei Jie Chen Xiu-Guang Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期337-342,共6页
Phase transition of polycrystalline iron compressed along the Hugoniot is studied by combining laser-driven shock with in situ x-ray diffraction technique.It is suggested that polycrystalline iron changes from an init... Phase transition of polycrystalline iron compressed along the Hugoniot is studied by combining laser-driven shock with in situ x-ray diffraction technique.It is suggested that polycrystalline iron changes from an initial body-centered cubic structure to a hexagonal close-packed structure with increasing pressure(i.e.,a phase transition fromαtoε).The relationship between density and pressure for polycrystalline iron obtained from the present experiments is found to be in good agreement with the gas-gun Hugoniot data.Our results show that experiments with samples at lower temperatures under static loading,such as in a diamond anvil cell,lead to higher densities measured than those found under dynamic loading.This means that extrapolating results of static experiments may not predict the dynamic responses of materials accurately.In addition,neither the face-centered cubic structure seen in previous molecular-dynamics simulations or twophase coexistence are found within our experimental pressure range. 展开更多
关键词 in situ x-ray diffraction phase transition polycrystalline iron
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Revisit of the anisotropic vortex states of 2H-NbSe_(2) towards the zero-field limit
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作者 张凡 侯兴元 +5 位作者 姜宇轩 张宗源 涂玉兵 朱相德 陈根富 单磊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期80-86,共7页
We revisited the vortex states of 2H-NbSe_(2) towards zero fields by a low-temperature scanning tunneling microscope.Fine structures of the anisotropic vortex states were distinguished, one is a spatially non-splittin... We revisited the vortex states of 2H-NbSe_(2) towards zero fields by a low-temperature scanning tunneling microscope.Fine structures of the anisotropic vortex states were distinguished, one is a spatially non-splitting zero bias peak, and the other is an in-gap conductance anomaly resembling evolved crossing features around the center of the three nearest vortices.Both of them distribute solely along the next nearest neighboring direction of the vortex lattice and become unresolved in much higher magnetic fields, implying an important role played by the vortex–vortex interactions. To clarify these issues,we have studied the intrinsic vortex states of the isolated trapped vortex in zero fields at 0.45 K. It is concluded that the anisotropic zero bias peak is attributed to the superconducting gap anisotropy, and the spatially evolved crossing features are related to the vortex–vortex interaction. The vortex core size under the zero-field limit is determined. These results provide a paradigm for studying the inherent vortex states of type-II superconductors especially based on an isolated vortex. 展开更多
关键词 vortex states zero-bias conductance peak scanning tunneling microscopy
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A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor
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作者 Yi Zhao Wangchen Xue +62 位作者 Shaolin Xiong Qi Luo Yuanhao Wang Jiacong Liu Heng Yu Xiaoyun Zhao Yue Huang Jinyuan Liao Jianchao Sun Xiaobo Li Qibin Yi Ce Cai Shuo Xiao Shenglun Xie Chao Zheng Yanqiu zhang Chenwei Wang Wenjun Tan Zhiwei Guo Chaoyang Li Zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo Jiang He Jianjian He Bing Li Gang Li Xinqiao Li Jing Liang Xiaohua Liang Yaqing Liu Xiang Ma Rui Qiao Liming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen Hong Wu Yanbing Xu Sheng Yang Dali zhang fan zhang Hongmei zhang Peng zhang Shu zhang Zhen zhang Shijie Zheng Keke zhang Xingbo Han Haiyan Wu Hu Tai Hao Geng Gaopeng Lu Wei Xu fanchao Lyu Hongbo zhang fangjun Lu Shuangnan zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第10期25-35,共11页
Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up observations.Localization based on the relative counts of different detectors has b... Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up observations.Localization based on the relative counts of different detectors has been widely used for all-sky gamma-ray monitors.There are two major methods for this count distribution localization:χ^(2)minimization method and the Bayesian method.Here we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2)method.With comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2)method,especially for weak bursts.We further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location templates.Our method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations. 展开更多
关键词 methods:data analysis methods:analytical (stars:)gamma-ray burst:general
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