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阿尔茨海默病居家筛查专家共识 被引量:1
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作者 徐群 JWesson Ashford +29 位作者 陈彪 陈树斌 Jeffrey Cummings 顾柏俊 郭起浩 韩璎 花迎雪 金华 Nagaendran Kandiah 李海雁 刘晓蕾 刘新 卢佩琳 裴中 施晓耕 孙凯 汤彬 Goerge Vradenburg 王惠芳 王军 王晓明 王艳蕊 王艳梅 王玉林 翁文锋 辛美哲 张玉兰 赵禾欣 周显波 王虹峥 《阿尔茨海默病及相关病杂志》 2024年第3期176-183,共8页
老年人痴呆或认知障碍多由一种以上年龄相关的常见脑部疾病所致。阿尔茨海默病(Alzheimer's disease,AD)是其中最常见的神经变性疾病,且是全球前10位死因中唯一无法治愈或缺乏长期对症疗效的疾病,给个人、家庭和全球经济都带来了巨... 老年人痴呆或认知障碍多由一种以上年龄相关的常见脑部疾病所致。阿尔茨海默病(Alzheimer's disease,AD)是其中最常见的神经变性疾病,且是全球前10位死因中唯一无法治愈或缺乏长期对症疗效的疾病,给个人、家庭和全球经济都带来了巨大的负担。早期及时发现和干预是对抗AD的最佳策略。在过去的30年中,许多研究都提出了降低痴呆风险的方法,2020年《柳叶刀》杂志的痴呆预防报告已阐明通过应对风险因素可以预防或延缓超过40%的痴呆。然而,目前全球医疗体系尚未具备早期或及时发现AD的足够能力。最近的一项研究发现,只有不到10%的轻度认知障碍(mild cognitive impairment,MCI)是在初级医疗机构中诊断出来的。近来,抗淀粉样蛋白β(Amyloid beta,Aβ)抗体药物lecanemab和donanemab被批准上市用于早期AD治疗,以及30年的随访研究证明改善风险因素显著减少AD痴呆的发病率并延长了寿命,使得人们对AD早期识别的关注迅速增加。阿尔茨海默病防治协会(China Association for Alzheimer's Disease,CAAD)认识到居家早期和及时发现AD的重要性,并成立了一个由协会成员、临床医生和研究人员组成的全球AD多领域专家团队,就以下目标达成共识:①为个人、家庭、社区、协会和组织提供专家指导意见;②介绍用于认知障碍和痴呆居家筛查的数字工具和可用资源,并为AD高危人群或疑似患者制定下一步应对策略;③讨论现有可用或将来可能的居家筛查适宜AD生物标志物;④为未来的改进和全球应用建立可行性框架。专家组对于当前可用的证据、工具和资源进行综述,并进一步考量其在AD居家筛查中的价值。 展开更多
关键词 认知评估 阿尔茨海默病 认知障碍 痴呆 居家 筛查
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Clinical Application of Sex Hormone in Different Physiological Periods in the Diagnosis of Infertility Patients
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作者 Jianhong Nong Daxian Tan +4 位作者 Arshad Mehmood Tingchao Wang xin liu Li Deng Bowen Wei 《Natural Science》 2024年第6期102-110,共9页
Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different ... Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different physiological periods in the diagnosis of infertility patients. Methods: From December 2019 to May 2021, a total of 93 infertility patients were admitted and selected as the observation group. Among them, 31 cases were in the follicular stage, 31 cases in the ovulation stage, and 31 cases in the luteal stage. Ninety-three healthy women for fertility evaluation due to male infertility were selected as the control group. The control group included 31 women in the follicular phase, 31 women in the ovulatory phase, and 31 women in the luteal phase. The levels of sex hormones (prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), testosterone (T), and progesterone (P)) during different physiological phases were compared between the observation and control groups. Results: The follicular phase showed no significant difference in LH levels between the observation group and the control group. The observation group showed higher levels of PRL and P compared to the control group, while the levels of FSH, E2, and T were lower in the observation group compared to the control group. The ovulation phase showed no significant difference in PRL levels between the two groups. The observation group showed lower levels of LH, FSH, E2, T, and P compared to the control group. The luteal phase showed no statistical difference in E2 levels between the two groups. The observation group showed higher levels of PRL, LH, and FSH compared to the control group, while the levels of T and P were lower in the observation group compared to the control group. Conclusion: Infertile women show variations in hormone levels compared to the normal levels during the follicular phase, ovulatory phase, and luteal phase. 展开更多
关键词 Different Periods Sex Hormone Level Detection INFERTILITY Auxiliary Diagnosis
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Graded and Quantitative Technology and Application of Coal-Bearing Reservoir Based on Seismic Reflection Characteristics
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作者 Hao Zhang Huan Wan +7 位作者 Liming Lin Wenjun xing Tiemei Yang Longgang Zhou Lijun Gao Guangchao Zhi xin liu Xiaowen Song 《Journal of Geoscience and Environment Protection》 2024年第6期279-290,共12页
Taiyuan formation is the main exploration strata in Ordos Basin, and coals are widely developed. Due to the interference of strong reflection of coals, we cannot completely identify the effective reservoir information... Taiyuan formation is the main exploration strata in Ordos Basin, and coals are widely developed. Due to the interference of strong reflection of coals, we cannot completely identify the effective reservoir information of coal-bearing reservoir on seismic data. Previous researchers have studied the reservoir by stripping or weakening the strong reflection, but it is difficult to determine the effectiveness of the remaining reflection seismic data. In this paper, through the establishment of 2D forward model of coal-bearing strata, the corresponding geophysical characteristics of different reflection types of coal-bearing strata are analyzed, and then the favorable sedimentary facies zones for reservoir development are predicted. On this basis, combined with seismic properties, the coal-bearing reservoir is quantitatively characterized by seismic inversion. The above research shows that the Taiyuan formation in LS block of Ordos Basin is affected by coals and forms three or two peaks in different locations. The reservoir plane sedimentary facies zone is effectively characterized by seismic reflection structure. Based on the characteristics of sedimentary facies belt and petrophysical analysis, the reservoir is semi quantitatively characterized by attribute analysis and waveform indication, and quantitatively characterized by pre stack geostatistical inversion. Based on the forward analysis of coal measure strata, this technology characterizes the reservoir facies belt through seismic reflection characteristics, and describes coal measure reservoirs step by step. It effectively guides the exploration of LS block in Ordos Basin, and has achieved good practical application effect. 展开更多
关键词 Coal-Bearing Reservoir Seismic Reflection Characteristics Waveform Indication Inversion Geostatistics Inversion
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Multifaceted roles of LhWRKY44 in promoting anthocyanin accumulation in Asiatic hybrid lilies (Lilium spp.)
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作者 Mengmeng Bi Rui Liang +8 位作者 Jiawen Wang Yuxiao Qu xin liu Yuwei Cao Guoren He Yue Yang Panpan Yang Leifeng Xu Jun Ming 《Horticulture Research》 SCIE CSCD 2023年第9期260-274,共15页
The Asiatic hybrid lily(Lilium spp.)is a horticultural crop with high commercial value and diverse anthocyanin pigmentation patterns.However,the regulatory mechanism underlying lily flower color has been largely unexp... The Asiatic hybrid lily(Lilium spp.)is a horticultural crop with high commercial value and diverse anthocyanin pigmentation patterns.However,the regulatory mechanism underlying lily flower color has been largely unexplored.Here,we identified a WRKY transcription factor from lily tepals,LhWRKY44,whose expression was closely associated with anthocyanin accumulation.Functional verification indicated that LhWRKY44 positively regulated anthocyanin accumulation.LhWRKY44 physically interacted with LhMYBSPLATTER and directly bound to the LhMYBSPLATTER promoter,which enhanced the effect of the LhMYBSPLATTER-LhbHLH2 MBW complex activator on anthocyanin accumulation.Moreover,EMSA and dual-luciferase assays revealed that LhWRKY44 activated and bound to the promoters of gene LhF3H and the intracellular anthocyanin-related glutathione S-transferase gene LhGST.Interestingly,our further results showed that LhWRKY44 participated in light and drought-induced anthocyanin accumulation,and improved the drought tolerance in lily via activating stress-related genes.These results generated a multifaceted regulatory mechanism for the LhWRKY44-meditaed enhancement by the environmental signal pathway of anthocyanin accumulation and expanded our understanding of the WRKY-mediated transcriptional regulatory hierarchy modulating anthocyanin accumulation in Asiatic hybrid lilies. 展开更多
关键词 spp. DROUGHT ANTHOCYANIN
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CircCCND1调节miR-340-5p/TGIF1轴对H446肺癌细胞恶性生物学行为的影响
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作者 董怡 朱翠敏 +2 位作者 柳新 赵继伟 李青山 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第3期161-169,共9页
背景与目的 肺癌是常见的肺部恶性肿瘤,探究肺癌发生发展的分子机制是当前研究的热点。环状RNA细胞周期蛋白D1 (circular RNA Cyclin D1,CircCCND1)在肺癌中高表达,可能是治疗肺癌的潜在靶点。本研究旨在探讨CircCCND1调节miR-340-5p/... 背景与目的 肺癌是常见的肺部恶性肿瘤,探究肺癌发生发展的分子机制是当前研究的热点。环状RNA细胞周期蛋白D1 (circular RNA Cyclin D1,CircCCND1)在肺癌中高表达,可能是治疗肺癌的潜在靶点。本研究旨在探讨CircCCND1调节miR-340-5p/转化生长因子β诱导因子同源框1 (transforming growth factor β-induced factor homeobox 1,TGIF1)轴对肺癌细胞恶性生物学行为的影响。方法 检测人正常肺上皮细胞BEAS-2B及人肺癌H446细胞中CircCCND1、miR-340-5p及TGIF1 mRNA表达。将体外培养的H446细胞分为对照组、CircCCND1 siRNA组、miR-340-5p mimics组、阴性对照组、CircCCND1 siRNA+miR-340-5p inhibitor组,检测细胞增殖、线粒体膜电位、凋亡、迁移和侵袭情况,以及各组细胞CircCCND1、miR-340-5p、TGIF1 mRNA、BCL2相关X蛋白(BCL2-associated X protein,Bax)、剪切的半胱天冬氨酸蛋白酶3 (cleaved Caspase-3)、N-钙黏蛋白(N-cadherin)、E-钙黏蛋白(E-cadherin)、TGIF1蛋白表达,并验证miR-340-5p与CircCCND1、TGIF1的靶向关系。结果 与BEAS-2B细胞相比,H446细胞CircCCND1、TGIF1 mRNA升高,miR-340-5p表达降低(P<0.05)。敲低CircCCND1或上调miR-340-5p表达可抑制H446细胞增殖、迁移、侵袭,降低TGIF1 mRNA和TGIF1蛋白表达,促进细胞凋亡;下调miR-340-5p可拮抗敲低CircCCND1对H446肺癌细胞恶性生物学行为的抑制作用。CircCCND1可能靶向下调miR-340-5p,miR-340-5p可能靶向下调TGIF1。结论 敲低CircCCND1可抑制肺癌H446细胞恶性行为,其作用可能是通过调控miR-340-5p/TGIF1轴实现的。 展开更多
关键词 CircCCND1 miR-340-5p/TGIF1 肺肿瘤 恶性生物学行为
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Calcium-chelating peptides from rabbit bone collagen:characterization,identification and mechanism elucidation 被引量:2
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作者 Fuhuan Yuan Yu Fu +8 位作者 Liang Ma Hankun Zhu Yong Yu xin Feng Yi Sun Hongjie Dai xin liu Zhengfang liu Yuhao Zhang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1485-1493,共9页
This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instan... This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating mechanism.Collagen peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were investigated.The structural characterization revealed that RBCP successfully chelated with calcium ions.Furthermore,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two peptides.Overall,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides. 展开更多
关键词 Rabbit bone Collagen peptide Peptide-calcium chelate Chelation mechanism Liquid chromatography-tandem mass(LC-MS/MS)
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Active MoS_(2)-based electrode for green ammonia synthesis 被引量:1
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作者 xin liu Lei Yang +2 位作者 Tao Wei Shanping liu Beibei Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期268-275,共8页
Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology i... Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments. 展开更多
关键词 Nitrogen reduction reaction Density functional theory calculations Molybdenum disulfide ELECTROCHEMISTRY CATALYST THERMODYNAMICS
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多位点隔离的金属催化剂用于高效选择性加氢
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作者 任小敏 戴慧聪 +1 位作者 刘鑫 杨启华 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第7期108-123,共16页
负载型金属催化剂(SMC)广泛用于多相加氢反应.然而,在大多数报道的双/多位点SMC中,由于不同活性位点之间几何和电子结构性质的相互影响,往往难以仅调整某一特定位点的性质而不波及其他位点.这种限制导致了一个常见的现象:在提高反应选... 负载型金属催化剂(SMC)广泛用于多相加氢反应.然而,在大多数报道的双/多位点SMC中,由于不同活性位点之间几何和电子结构性质的相互影响,往往难以仅调整某一特定位点的性质而不波及其他位点.这种限制导致了一个常见的现象:在提高反应选择性的同时,往往伴随着催化剂活性的降低.空间隔离的双位点催化剂因其两个活性位点之间没有直接接触,使得实现活性位点的独立调控成为可能.此外,双位点SMC还有助于研究每个活性位点的功能,以阐明这些位点在催化反应中的协同机制.因此,本文系统地总结了位点孤立的SMC的制备及其在选择性氢化反应中的最新进展.本文从用于加氢反应的孤立位点SMC的分类入手,综述了两种不同金属纳米粒子、单原子和金属纳米粒子、多孔材料和金属纳米粒子以及金属络合物和金属纳米粒子的协同作用,探讨了氢溢流效应在双孤立位点SMC体系协同机制中的重要作用.系统介绍了氢溢流的载体、距离及溢流的活性氢物种加氢能力.深入探讨了不同双孤立位点SMC的催化活性和选择性提高的经典案例及内在协同机制.还讨论了双孤立位点催化剂合成中所面临的机遇和挑战.在此基础上,对双孤立位点SMC的发展进行了展望.通过对具有不同孤立位点SMC在选择性加氢反应中的案例分析,总结了孤立位点SMC的协同作用机制.具体而言,两个孤立位点各司其职,分别用于氢气解离和不饱和基团活化或者在串联反应中独立催化不同的反应过程,以氢溢流为桥梁,实现这两个过程的联动,最终提升了催化性能.在选择性氢化反应之外,双孤立位点协同概念在氧化反应、光催化体系和电催化体系也有重要作用.相比传统催化剂,孤立位点SMC的构筑更具有挑战性.随着表征手段的日益发展,孤立位点SMC催化剂结构得到了更为精确测定.双孤立位点SMC的协同体系有望拓展至均多相催化剂耦合以及与酶催化耦合实现生物-催化的协同.在SMC催化剂制备方面需要发展更有效的方法控制孤立位点的密度及空间距离.孤立位点催化体系的拓展和优化将加速新型高效选择性氢化催化剂的开发,促进更明确的构效关系的研究,同时也为拓展孤立位点SMC在其他催化体系的应用奠定基础.综上所述,本文综述了基于金属-金属、金属-单原子、金属-多孔材料以及金属-金属配合物的双孤立位点SMC的构筑及在选择性加氢反应中的性能研究.已有的研究表明,双孤立位点的协同效应显著提升了催化活性和选择性.此外,对具有明确结构的双孤立位点SMC的构效关系研究揭示了其协同机制.尽管双孤立位点SMC在精准制备和表征方面仍面临挑战,但随着催化剂合成策略及更先进表征手段的发展,高效稳定的双孤立位点SMC将在选择氢化领域得到更广泛的应用. 展开更多
关键词 选择性加氢 协同催化 孤立位点 多位点分离 负载金属催化剂
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电荷分离和转移调控光催化剂稳定的Pickering乳液用于光-酶偶联催化
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作者 刘嘉立 戴慧聪 +3 位作者 刘鑫 任亦起 王茂弟 杨启华 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期114-122,共9页
人类社会可持续发展面临的能源紧缺和环境污染等问题迫切需要化工生产向绿色、低碳转型.酶催化反应因具有高活性、高选择性、专一性和低能耗等优点,在化工和制药行业得到了广泛应用.其中,氧化还原酶催化反应是还原醇类、胺类、酮类、酸... 人类社会可持续发展面临的能源紧缺和环境污染等问题迫切需要化工生产向绿色、低碳转型.酶催化反应因具有高活性、高选择性、专一性和低能耗等优点,在化工和制药行业得到了广泛应用.其中,氧化还原酶催化反应是还原醇类、胺类、酮类、酸类和无机底物的有效方法,该类反应通常需要采用还原型辅酶NAD(P)(H)作为还原剂,而NAD(P)(H)的昂贵价格严重制约了酶催化反应的工业化发展.受自然界中光合作用启发,光催化辅酶再生技术通过将酶催化与光催化技术耦合,旨在常温常压的温和反应条件下利用太阳能实现化学品的高效、绿色合成.迄今为止,虽然已有多种类型的光催化剂被用于光催化NAD(P)H再生,但电荷分离效率低、电子/质子转移效率低、有机底物在水溶液中的溶解度低以及酶失活等仍是光-酶偶联系统亟待解决的问题.针对酶失活的问题,研究人员通过Pickering乳液催化技术利用固体颗粒直接乳化两相体系,进而构建高效的生物催化反应体系,提高催化反应效率.Pickering乳液中固体乳化剂吸附在水油界面形成的稳固空间壳层不仅可以将酶限域,而且可以像在细胞中一样为酶提供合适的微环境和足够的自由度.另外,Pickering乳液的高反应界面也可以解决底物在反应相中溶解度低的问题,实现类似细胞的功能和长期连续流动的生物催化,是构建仿生微反应器的理想平台.本文采用电子传递介质固载化界面活性复合光催化剂为固体乳化剂,ADH和NAD+为生物催化单元,开发了一种基于Pickering乳液的人工光-酶偶联体系.针对光敏剂中电荷分离和转移以及光敏剂向NAD(P)H的电子转移效率低等问题,光催化体系采用溶胶凝胶法制备了具有异质结结构的共价聚合物-氧化钛复合材料光催化剂.共价聚合物和氧化钛之间的高界面面积有效地提高了电荷分离效率,共价聚合物含量优化后的光催化剂在可见光下NADH再生的TOF值可达5.5 mmol·g^(-1)·h^(-1),是对应纳米共价聚合物与无定形氧化钛物理混合物的27.5倍.随后进一步将电子传递介质[Cp^(*)Rh(bpy)H_(2)O]^(2+)(简称M)通过嫁接法固载到光催化剂上,电子传递距离的缩短和场效应有效促进了电荷分离以及光生电子从光催化剂到电子传递介质的传递,同时解决了电子传递介质回收繁琐和酶失活的问题.得到的光催化剂在可见光下催化NADH再生反应的TOF值为2.4 mmol·g^(-1)·h^(-1),远高于其对应的物理混合物.最后分别以长碳链硅烷修饰后具有界面活性的光催化剂为固体乳化剂,辅酶、酶以及牺牲剂为水相,正己烷及底物正丁醛为油相制备了光催化反应与酶催化反应偶联的Pickering乳液人工光-酶偶联体系.可见光下Pickering乳液有效催化还原正丁醛,在6 h内累积生成了16.1 mmol·L^(-1)的丁醇,相当于NADH再生循环14次.综上,本文以制备具有异质结结构的高效复合光催化剂为切入点,理性设计出了高效Pickering乳液光-酶偶联体系,为构建高效的光-酶偶联体系,缓解能源和环境危机、实现碳减排提供了一种有效策略. 展开更多
关键词 光催化 NADH再生 聚合物 电子传递介质 Pickering乳液
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电催化还原氮制氨的最新进展
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作者 海广通 富忠恒 +1 位作者 刘欣 黄秀兵 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期107-127,共21页
氮还原反应在生态系统、农业系统和工业氮循环中发挥着至关重要的作用.然而,由于氮气在水中的溶解度低,N≡N三键结构稳定,且存在与析氢反应的激烈竞争,因此目前电化学氮还原反应面临着产率缓慢、法拉第效率低等挑战.尽管研究者们通过不... 氮还原反应在生态系统、农业系统和工业氮循环中发挥着至关重要的作用.然而,由于氮气在水中的溶解度低,N≡N三键结构稳定,且存在与析氢反应的激烈竞争,因此目前电化学氮还原反应面临着产率缓慢、法拉第效率低等挑战.尽管研究者们通过不懈的努力已经在该领域取得了显著的进展,但距离其实际应用仍有较大差距.因此,如何通过多方面的调控手段,尽早实现人工固氮的工业化生产,成为当前该领域亟待解决的关键问题.本文系统梳理了电催化还原氮制氨的最新进展.首先,对NRR的机理进行了全面介绍.详细介绍了五种备受关注的氮还原机理:解离机理、结合机理、交替机理、酶促机理以及最新发现的马尔斯-范克雷维伦机理.通过对比电催化氮还原与哈珀法催化氮还原的反应机理,阐明了电催化氮还原的优势.然后,总结了该领域最新的研究进展.详细介绍了高性能氮还原催化剂的最新设计开发成果,基于近五年的相关报道,重点介绍了Mo基催化剂、Cu基催化剂、Ru基催化剂、Bi基催化剂和Fe基催化剂的研究进展.此外,对其他过渡金属基催化剂和非金属催化剂也进行了评述和展望,并对不同催化剂的优缺点进行了系统的比较.随后,对新型氮还原反应装置的研究进展进行了综述.讨论了新型反应器对缓解氮分子低溶解度这一问题的关键作用,强调了研发新型氮还原反应装置对提升电催化氮还原性能的重要性.在NRR反应路径的调控和优化方面,本文总结了最新的研究成果,特别是Li介导的氮还原反应的重要意义,证实了反应路径的调控优化是提升氮还原性能的有效手段.更为重要的是,从目前最新的研究成果出发,提出了氮还原性能的提升需要多方面的协同调控,单一的优化手段难以突破现有的瓶颈,这为后续的研究提供了重要参考.在展望部分,强调了氮还原领域目前面临的挑战并讨论了未来的研究方向.综上,本文系统地总结了近年来的研究进展,包括高性能催化剂、新型反应设备以及氮还原反应路径的调控和优化.提升氮还原反应的整体性能需要多方面的协调调控,仅关注催化剂很难取得重大突破.本文旨在为氮还原催化剂和反应器的设计以及反应路径的调控优化提供参考. 展开更多
关键词 氮还原反应 电催化 催化剂 反应设备 反应途径
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Evolutionary Neural Architecture Search and Its Applications in Healthcare 被引量:1
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作者 xin liu Jie Li +3 位作者 Jianwei Zhao Bin Cao Rongge Yan Zhihan Lyu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期143-185,共43页
Most of the neural network architectures are based on human experience,which requires a long and tedious trial-and-error process.Neural architecture search(NAS)attempts to detect effective architectures without human ... Most of the neural network architectures are based on human experience,which requires a long and tedious trial-and-error process.Neural architecture search(NAS)attempts to detect effective architectures without human intervention.Evolutionary algorithms(EAs)for NAS can find better solutions than human-designed architectures by exploring a large search space for possible architectures.Using multiobjective EAs for NAS,optimal neural architectures that meet various performance criteria can be explored and discovered efficiently.Furthermore,hardware-accelerated NAS methods can improve the efficiency of the NAS.While existing reviews have mainly focused on different strategies to complete NAS,a few studies have explored the use of EAs for NAS.In this paper,we summarize and explore the use of EAs for NAS,as well as large-scale multiobjective optimization strategies and hardware-accelerated NAS methods.NAS performs well in healthcare applications,such as medical image analysis,classification of disease diagnosis,and health monitoring.EAs for NAS can automate the search process and optimize multiple objectives simultaneously in a given healthcare task.Deep neural network has been successfully used in healthcare,but it lacks interpretability.Medical data is highly sensitive,and privacy leaks are frequently reported in the healthcare industry.To solve these problems,in healthcare,we propose an interpretable neuroevolution framework based on federated learning to address search efficiency and privacy protection.Moreover,we also point out future research directions for evolutionary NAS.Overall,for researchers who want to use EAs to optimize NNs in healthcare,we analyze the advantages and disadvantages of doing so to provide detailed guidance,and propose an interpretable privacy-preserving framework for healthcare applications. 展开更多
关键词 Neural architecture search evolutionary computation large-scale multiobjective optimization distributed parallelism healthcare
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Bifunctional TiO_(2-x)nanofibers enhanced gel polymer electrolyte for high performance lithium metal batteries 被引量:1
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作者 Yixin Wu Zhen Chen +6 位作者 Yang Wang Yu Li Chunxing Zhang Yihui Zhu Ziyu Yue xin liu Minghua Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期437-448,I0011,共13页
Exploration of advanced gel polymer electrolytes(GPEs)represents a viable strategy for mitigating dendritic lithium(Li)growth,which is crucial in ensuring the safe operation of high energy density Li metal batteries(L... Exploration of advanced gel polymer electrolytes(GPEs)represents a viable strategy for mitigating dendritic lithium(Li)growth,which is crucial in ensuring the safe operation of high energy density Li metal batteries(LMBs).Despite this,the application of GPEs is still hindered by inadequate ionic conductivity,low Li^(+)transference number,and subpar physicochemical properties.Herein,Ti O_(2-x)nanofibers(NF)with oxygen vacancy defects were synthesized by a one-step process as inorganic fillers to enhance the thermal/mechanical/ionic-transportation performances of composite GPEs.Various characterizations and theoretical calculations reveal that the oxygen vacancies on the surface of Ti O_(2-x)NF accelerate the dissociation of Li PF_6,promote the rapid transfer of free Li^(+),and influence the formation of Li F-enriched solid electrolyte interphase.Consequently,the composite GPEs demonstrate enhanced ionic conductivity(1.90m S cm^(-1)at room temperature),higher lithium-ion transference number(0.70),wider electrochemical stability window(5.50 V),superior mechanical strength,excellent thermal stability(210℃),and improved compatibility with lithium,resulting in superior cycling stability and rate performance in both Li||Li,Li||Li Fe PO_(4),and Li||Li Ni_(0.8)Co_(0.1)Mn_(0.1)O_(2)cells.Overall,the synergistic influence of nanofiber morphology and enriched oxygen vacancy structure of fillers on electrochemical properties of composite GPEs is comprehensively investigated,thus,it is anticipated to shed new light on designing high-performance GPEs LMBs. 展开更多
关键词 Nanofibers fillers Oxygen vacancies Gel polymer electrolytes Lithium metal batteries
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“禁、限”政策能否长效缓解交通治理困境?——基于替代效应的实证分析
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作者 肖潇 程跃 刘鑫 《公共行政评论》 CSSCI 北大核心 2024年第5期4-25,196,共23页
“禁、限”政策常被用以解决交通治理问题,从禁止摩托车到限制电动车再到限行燃油车,但“禁、限”政策能否长效解决政府交通治理难题,仍是一个尚未得到检验的问题。论文基于绿色低碳、可持续的政府发展目标,以各类交通工具对城市负外部... “禁、限”政策常被用以解决交通治理问题,从禁止摩托车到限制电动车再到限行燃油车,但“禁、限”政策能否长效解决政府交通治理难题,仍是一个尚未得到检验的问题。论文基于绿色低碳、可持续的政府发展目标,以各类交通工具对城市负外部性影响程度,即“污染”“事故率”“拥堵率”为衡量指标对出行工具进行了分类。从民众视角和政府视角出发,找出双方对出行工具选择的矛盾点,并以此构建了替代分析模型。从调整车辆结构占比以达成治理目标为研究逻辑,找出平衡政府和民众不同利益诉求的动态均衡方式。研究发现,“禁、限”政策对交通治理成效存在双路径:其一是出行需求向绿色低碳、可持续出行工具转移,这种转移方式会促使政府和民众达成利益均衡,实现交通的长效治理。其二是出行需求向个体交通体系转移,该种转移方式仅满足了民众出行需求,但不符合政府治理目标,会陷入“禁止——替代品出现——禁止替代品——新替代品出现”的循环困境。 展开更多
关键词 替代效应 马尔科夫预测模型 绿色低碳 治理创新 政策评估
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Development of a new cerebral ischemia reperfusion model of Mongolian gerbils and standardized evaluation system 被引量:1
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作者 Ying Wu Caijiao Hu +9 位作者 Zhihui Li Feiyang Li Jianyi Lv Meng Guo xin liu Changlong Li Xueyun Huo Zhenwen Chen Lifeng Yang Xiaoyan Du 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期48-55,共8页
Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symp... Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications. 展开更多
关键词 ISCHEMIA/REPERFUSION Mongolian gerbil standardized model system unilateral carotid occlusion
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6,6'-二溴-1,1'-联-2-萘酚的偶联合成与手性拆分——对一个有机化学综合实验的改进与发展
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作者 邸士睿 王帅 +1 位作者 刘鑫 朱红平 《大学化学》 CAS 2024年第1期287-293,共7页
6,6'-二溴-1,1'-联-2-萘酚是1,1'-联-2-萘酚(BINOL)的衍生物,两者同为典型的轴手性有机物分子,这类分子的合成与拆分研究对于本科生深入认识和理解轴手性类化合物具有重要意义,本实验考虑到(±)-BINOL及其衍生物的价格... 6,6'-二溴-1,1'-联-2-萘酚是1,1'-联-2-萘酚(BINOL)的衍生物,两者同为典型的轴手性有机物分子,这类分子的合成与拆分研究对于本科生深入认识和理解轴手性类化合物具有重要意义,本实验考虑到(±)-BINOL及其衍生物的价格较为高昂,不适合开展大批量合成和拆分的教学实验,因此采用了微波合成的方式实现6,6'-二溴-1,1'-联-2-萘酚的偶联合成。除此之外,本实验还开发了拆分剂N-苄基氯化辛可尼丁的微波合成方法,并用合成的N-苄基氯化辛可尼丁直接对6,6'-二溴-1,1'-联-2-萘酚进行化学拆分。本实验通过引入微波合成、改良合成反应用溶剂以及回收拆分剂等方式使实验更加符合绿色化学的宗旨。在教学效果上,本实验涉及的操作较多,有助于考查学生的综合实验水平,更富教学价值,具有强的实践意义。 展开更多
关键词 BINOL及其衍生物 微波合成 手性拆分 化学实验教学
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基于思维导图的临床技能教学研究与应用——以心肺复苏课为例 被引量:1
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作者 张萍 陈贵娥 +3 位作者 刘新 唐靖 莫桂熙 张良清 《中国高等医学教育》 2024年第6期115-117,共3页
在高等医学院校的临床教学中,师生间创建有效的教学联系对于提高临床教学效率和教学质量具有重要意义。本研究借助思维导图展现师生间的教学联系,将课前学情与学生需求、课堂出勤、课后学生反馈和教师反馈等复杂抽象的教学元素转变为直... 在高等医学院校的临床教学中,师生间创建有效的教学联系对于提高临床教学效率和教学质量具有重要意义。本研究借助思维导图展现师生间的教学联系,将课前学情与学生需求、课堂出勤、课后学生反馈和教师反馈等复杂抽象的教学元素转变为直观形象的教学关系图,使师生间联系更加可视化、脉络化。结合临床实验教学要求,通过将思维导图应用在2016级本科生心肺复苏术临床技能课程教学中,协助师生建立了有效的教学联系,加强教学沟通,同时优化了临床教学方案,应用效果显著。 展开更多
关键词 思维导图 临床实践教学 教学联系 心肺复苏
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Design and additive manufacturing of bionic hybrid structure inspired by cuttlebone to achieve superior mechanical properties and shape memory function
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作者 Luhao Yuan Dongdong Gu +8 位作者 xin liu Keyu Shi Kaijie Lin He liu Han Zhang Donghua Dai Jianfeng Sun Wenxin Chen Jie Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第5期189-206,共18页
Lightweight porous materials with high load-bearing,damage tolerance and energy absorption(EA)as well as intelligence of shape recovery after material deformation are beneficial and critical for many applications,e.g.... Lightweight porous materials with high load-bearing,damage tolerance and energy absorption(EA)as well as intelligence of shape recovery after material deformation are beneficial and critical for many applications,e.g.aerospace,automobiles,electronics,etc.Cuttlebone produced in the cuttlefish has evolved vertical walls with the optimal corrugation gradient,enabling stress homogenization,significant load bearing,and damage tolerance to protect the organism from high external pressures in the deep sea.This work illustrated that the complex hybrid wave shape in cuttlebone walls,becoming more tortuous from bottom to top,creates a lightweight,load-bearing structure with progressive failure.By mimicking the cuttlebone,a novel bionic hybrid structure(BHS)was proposed,and as a comparison,a regular corrugated structure and a straight wall structure were designed.Three types of designed structures have been successfully manufactured by laser powder bed fusion(LPBF)with NiTi powder.The LPBF-processed BHS exhibited a total porosity of 0.042% and a good dimensional accuracy with a peak deviation of 17.4μm.Microstructural analysis indicated that the LPBF-processed BHS had a strong(001)crystallographic orientation and an average size of 9.85μm.Mechanical analysis revealed the LPBF-processed BHS could withstand over 25000 times its weight without significant deformation and had the highest specific EA value(5.32 J·g^(−1))due to the absence of stress concentration and progressive wall failure during compression.Cyclic compression testing showed that LPBF-processed BHS possessed superior viscoelastic and elasticity energy dissipation capacity.Importantly,the uniform reversible phase transition from martensite to austenite in the walls enables the structure to largely recover its pre-deformation shape when heated(over 99% recovery rate).These design strategies can serve as valuable references for the development of intelligent components that possess high mechanical efficiency and shape memory capabilities. 展开更多
关键词 additive manufacturing laser powder bed fusion bionic structure CUTTLEBONE mechanical properties shape memory function
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Effects of pyraclostrobin on growth,oxidative stress,and gene expression in relation to stress and ATP-binding cassette transporters in Tetrahymena thermophila
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作者 Yang liu Jiale ZHANG +4 位作者 Peng XIAO xin liu Yisifu MA Jing ZHANG Bangjun ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期150-162,共13页
Pyraclostrobin(PYR),a widely used fungicide,has negative effects on fish and algae,but its toxicity in protozoa remains unclear.In this study,the effects of PYR on the growth,oxidative stress,and gene expression relat... Pyraclostrobin(PYR),a widely used fungicide,has negative effects on fish and algae,but its toxicity in protozoa remains unclear.In this study,the effects of PYR on the growth,oxidative stress,and gene expression related to stress and ATP-binding cassette(ABC)transporters in Tetrahymena thermophila were investigated.The result showed that the 96-h IC_(50)of PYR against T.thermophila was 17.2 mg/L.Moreover,PYR inhibited the growth of T.thermophila in concentration-or time-dependent manner.A morphological study revealed that the shape and size of T.thermophila changed,and damage of cell membrane surface was observed by scanning electron microscopy after 96 h of PYR exposure.The activities of superoxide dismutase(SOD)and catalase(CAT)increased throughout the experiment.In contrast,the glutathione(GSH)content was increased at 24 h and 48 h of exposure and decreased at 96 h.Moreover,a significant increase in malondialdehyde(MDA)level was observed in T.thermophila after96 h of exposure.Furthermore,PYR upregulated the HSP703,HSP705,GPx2,and ABAC15 gene expression in the 0.1–5-mg/L groups and downregulated the HSP704,HSP90,TGR,and ABCC52 mRNA levels at 96 h of exposure.These results suggest that PYR may exert adverse effects on T.thermophila by inducing oxidative stress and changing the gene expression related to ABC transporters and stress,which may enrich the understanding of the toxicity mechanism of PYR in aquatic organisms and provide reference data for aquatic ecological risk assessments. 展开更多
关键词 PYRACLOSTROBIN Tetrahymena thermophila GROWTH oxidative stress gene expression
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Innovative Mn_(3-x)O_(4-y)@NCA design:Leveraging Mn/O vacancies and amorphous architecture for enhanced sodium-ion storage
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作者 Kaijun Xie xin liu +7 位作者 Kai Xia Lipeng Diao Ping Lu Mengmeng Wang Long Fang Yihui Zou Dongjiang Yang Xiaodong Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期747-756,I0015,共11页
Manganese-based oxide electrode materials suffer from severe Jahn-Teller(J-T)distortion,leading to severe cycle instability in sodium ion storage.However,it is difficult to adjust the electron at d orbitals exactly to... Manganese-based oxide electrode materials suffer from severe Jahn-Teller(J-T)distortion,leading to severe cycle instability in sodium ion storage.However,it is difficult to adjust the electron at d orbitals exactly to a low spin state to eliminate orbital degeneracy and suppress J-T distortion fundamentally.This article constructed concentration-controllable Mn/O coupled vacancy and amorphous network in Mn_(3)O_(4) and coated it with nitrogen-doped carbon aerogel(Mn_(3-x)O_(4-y)@NCA).The existence of Mn/O vacancies has been confirmed by scanning transmission electron microscopy(STEM)and positron annihilation lifetime spectroscopy(PALS).Atomic absorption spectroscopy(AAS)and X-ray photoelectron spectroscopy(XPS)determine the most optimal ratio of Mn/O vacancies for sodium ion storage is 1:2.Density functional theory(DFT)calculations prove that Mn/O coupled vacancies with the ratio of 1:2could exactly induce a low spin states and a d~4 electron configuration of Mn,suppressing the J-T distortion successfully.The abundant amorphous regions can shorten the transport distance of sodium ions,increase the electrochemically active sites and improve the pseudocapacitance response.From the synergetic effect of Mn/O coupled vacancies and amorphous regions,Mn_(3-x)O_(4-y)@NCA exhibits an energy density of 37.5 W h kg^(-1)and an ultra-high power density of 563 W kg^(-1)in an asymmetric supercapacitor.In sodium-ion batteries,it demonstrates high reversible capacity and exceptional cycling stability.This research presents a new method to improve the Na^(+)storage performance in manganese-based oxide,which is expected to be generalized to other structural distortion. 展开更多
关键词 Manganese-based metal oxide Concentration-controllable Mn/O coupled vacancies Amorphous network Sodium ion supercapacitor Sodium ion battery
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Facile Semiconductor p-n Homojunction Nanowires with Strategic p-Type Doping Engineering Combined with Surface Reconstruction for Biosensing Applications
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作者 liuan Li Shi Fang +12 位作者 Wei Chen Yueyue Li Mohammad Fazel Vafadar Danhao Wang Yang Kang xin liu Yuanmin Luo Kun Liang Yiping Dang Lei Zhao Songrui Zhao Zongzhi Yin Haiding Sun 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期15-30,共16页
Photosensors with versatile functionalities have emerged as a cornerstone for breakthroughs in the future optoelectronic systems across a wide range of applications.In particular,emerging photoelectrochemical(PEC)-typ... Photosensors with versatile functionalities have emerged as a cornerstone for breakthroughs in the future optoelectronic systems across a wide range of applications.In particular,emerging photoelectrochemical(PEC)-type devices have recently attracted extensive interest in liquid-based biosensing applications due to their natural electrolyte-assisted operating characteristics.Herein,a PEC-type photosensor was carefully designed and constructed by employing gallium nitride(GaN)p-n homojunction semiconductor nanowires on silicon,with the p-GaN segment strategically doped and then decorated with cobalt-nickel oxide(CoNiO_(x)).Essentially,the p-n homojunction configuration with facile p-doping engineering improves carrier separation efficiency and facilitates carrier transfer to the nanowire surface,while CoNiO_(x)decoration further boosts PEC reaction activity and carrier dynamics at the nanowire/electrolyte interface.Consequently,the constructed photosensor achieves a high responsivity of 247.8 mA W^(-1)while simultaneously exhibiting excellent operating stability.Strikingly,based on the remarkable stability and high responsivity of the device,a glucose sensing system was established with a demonstration of glucose level determination in real human serum.This work offers a feasible and universal approach in the pursuit of high-performance bio-related sensing applications via a rational design of PEC devices in the form of nanostructured architecture with strategic doping engineering. 展开更多
关键词 p-n GaN nanowires Strategic p-doping Surface decoration Photoelectrochemical sensor Glucose sensing
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