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The 2-adic complexity of sum sequences of Legendre sequences
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作者 JING Xiaoyan XU Zhefeng FENG Keqin 《纯粹数学与应用数学》 2025年第2期191-199,共9页
Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequenc... Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequence of any k many Legendre sequences and show that the 2-adic complexity of the sum sequences of any k many Legendre sequences reaches the maximum by proving the case of k=2 and 3,which implies that the sum sequences can resist the attack of rational approximation algorithm. 展开更多
关键词 2-adic complexity binary sequences Legendre symbol Legendre sequences
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Crystal structure and antibacterial activity of two Gd_(2)complexes based on polydentate Schiff-base ligands
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作者 ZHANG Yingyue KANG Liuqing +2 位作者 YANG Yating GUAN Xiaofen WANG Wenmin 《无机化学学报》 北大核心 2025年第9期1867-1877,共11页
Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene... Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2. 展开更多
关键词 Gd_(2)complex polydentate Schiff base crystal structure DNA INTERACTION antibacterial activity
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Inhibition of the Arp2/3 Complex Attenuates Angiotensin Ⅱ-Induced Cardiomyocyte Hypertrophy
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作者 LING Li PAN Cong-Bin +2 位作者 WAN Lu-Xuan YANG Zhuang-Zhuang REN Zhan-Hong 《中国生物化学与分子生物学报》 北大核心 2025年第9期1332-1341,I0003-I0007,共15页
Pathological cardiac hypertrophy is an early and significant cardiac structural characteristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarge... Pathological cardiac hypertrophy is an early and significant cardiac structural characteristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarged cardiomyocyte.Effective intervention targets for abnormally enlarged cardiomyocyte remain to be identified.Previous studies have shown that the cellular shape and size can be regulated by the actin related protein 2/3(Arp2/3)complex,which is an actin-binding protein complex involved in the actin nucleation and assembly.However,the roles of the Arp2/3 complex in cardiomyocyte hypertrophy remain unknown.Here our study identifies its novel roles in the occurrence and development of cardiomyocyte hypertrophy.We found that mRNA levels of all subunits from the Arp2/3 complex are significantly upregulated(P<0.05)in the angiotensin Ⅱ(Ang Ⅱ)-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy.Further studies showed that siRNA-directed ARPC 2 silencing inhibits the reactivation of fetal genes and enlargement of cardiomyocyte area induced by Ang Ⅱ in neonatal rat primary cardiomyocytes(NRCMs)and H9c2 cells(P<0.05).In addition,the upstream activators of the Arp2/3 complex including SH3 protein interacting with Nck,90 kD(SPIN90)and Ras-related C3 botulinum toxin substrate 1(Rac1)/WASp family Verprolin-homologous protein-2(WAVE-2)are upregulated(P<0.05)in Ang Ⅱ-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy,indicating the excessive activation of the Arp2/3 complex.We further show that CK666,a specific Arp2/3 complex inhibitor,prevents the reactivation of fetal genes and the enlargement of cardiomyocyte area induced by Ang Ⅱ in NRCMs and H9c2 cells(P<0.05).Our results reveal that the Arp2/3 complex plays a crucial role in Ang Ⅱ-induced cardiomyocyte hypertrophy,which is beneficial to further studies about the molecular mechanisms by which the Arp2/3 complex regulates pathological cardiac hypertrophy. 展开更多
关键词 cardiomyocyte hypertrophy Arp2/3 complex angiotensinⅡ(AngⅡ) neonatal rat primary cardiomyocytes(NRCMs) H9c2 cells
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Effect of Jiawei Huangqi Guizhi decoction(加味黄芪桂枝汤)on theexpression of gastrin content and phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin complex 2 signallingpathways in rats with chronic atrophic gastritis
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作者 ZHOU Xia LIANG Kaiqing +4 位作者 CHEN Weigang CAO Yong DUO Hongdong LI Qiangbin AN Yun 《Journal of Traditional Chinese Medicine》 2025年第4期770-776,共7页
OBJECTIVE:To investigate the effects of Jiawei Huangqi Guizhi decoction(加味黄芪桂枝汤)on chronic atrophic gastritis(CAG)in rats and its modulation of the phosphatidylinositol 3-kinase/protein kinase B/mechanistic tar... OBJECTIVE:To investigate the effects of Jiawei Huangqi Guizhi decoction(加味黄芪桂枝汤)on chronic atrophic gastritis(CAG)in rats and its modulation of the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin complex 2(PI3K/Akt/m TORC2)signaling pathway.METHODS:CAG was induced in rats and treated with high-,medium-,or low-dose Jiawei Huangqi Guizhi decoction.Gastric histopathology was observed by hematoxylin and eosin staining.Serum levels of gastrin,PI3K,Akt,and m TORC2 were detected by enzyme-linked immunosorbent assay.Gene and protein expression levels were analyzed by reverse transcription polymerase chain reaction and western blot.RESULTS:The decoction alleviated gastric mucosal injury,reduced inflammation,and restored epithelial structure.It regulated PI3K,Akt,and m TORC2 expression at both m RNA and protein levels.CONCLUSION:Jiawei Huangqi Guizhi decoction may prevent CAG progression by improving gastric tissue and modulating the PI3K/Akt/m TORC2 signaling pathway. 展开更多
关键词 GASTRINS PI3K Akt mechanistic target of rapamycin complex 2 signal transduction PATHOLOGY Jiawei Huangqi Guizhi decoction
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Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),a new burbankite mineral from carbonatite-syenite complex in Shaxiongdong,Hubei,China
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作者 Jie Dai Xiao-dong Pan +10 位作者 Tong Wang Guo-wu Li Guan Wang Shang-ke Xie Jing Ren Kun-yang Wang Ting Li Tao Wang Jia-le He Jin-sha Xu Gan-fu Shen 《China Geology》 2025年第4期797-805,共9页
Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),is a new mineral species from Shaxiongdong,Hubei Province,China.It mainly occours as conchoidal crystals and with combination of hexagonal prism and pyramid and is associated with... Lishiite,(Ca_(2)□)Sr_(3)(CO_(3))_(5),is a new mineral species from Shaxiongdong,Hubei Province,China.It mainly occours as conchoidal crystals and with combination of hexagonal prism and pyramid and is associated with calcite,K-feldspar,albite,aegirine,apatite,and ancylite-(Ce)(?)and strontianite etc.Lishiite is brittle with conchiform fracture and has a Mohs hardness of approximately 4 and none cleavages were observed.The Vickers microhardness(VHN10)is 197.42 kg/mm^(2)(range:166.88 kg/mm^(2) to 214.58 kg/mm^(2)),and the calculated density of lishiite is 3.696 g/cm3.Hand specimen of lishiite are yellow-brown.The empirical chemical formula of the lishiite is ^(A)(Ca_(1.18)Sr_(0.25)Na_(0.19□1.38))_(Σ3.00)^( B)[Sr_(2.17)(Ce_(0.42)La_(0.24)Nd_(0.09)Eu_(0.01))_(Σ0.76) Ba_(0.07)]_(Σ3.00)(C_(5.05)O_(15)).As a member of the burbankite group,the general formula of lishiite follows the general formula A_(3)B_(3)(CO_(3))_(5),where A=Na,Ca,or and B=Sr,Ba,REE,or Ca.Its crystal structure is hexagonal(space group P6_(3)mc)with unit cell parameters a=10.4898(5)Å,c=6.4167(5)Å,and V=611.47(6)Å^(3),characterized by layers of AO_(8) and BO_(10) polyhedra connected to[CO_(3)]^(3−)groups.The discovery of lishiite provides new insights into the evolutionary history of rare earth element(REE)carbonate deposit formation. 展开更多
关键词 Lishiite (Ca_(2)□)Sr_(3)(CO_(3))_(5) New mineral species Burbankite group Carbonatite-syenite complex Mineral exploration engineering Shaxiongdong
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The Impact of Storyline Complexity on L2 Learners’Written Performance
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作者 CHEN Yu-lian 《Journal of Literature and Art Studies》 2024年第5期369-372,共4页
Task-based Language Teaching(TBLT)research has provided ample evidence that cognitive complexity is an important aspect of task design that influences learner’s performance in terms of fluency,accuracy,and syntactic ... Task-based Language Teaching(TBLT)research has provided ample evidence that cognitive complexity is an important aspect of task design that influences learner’s performance in terms of fluency,accuracy,and syntactic complexity.Despite the substantial number of empirical investigations into task complexity in journal articles,storyline complexity,one of the features of it,is scarcely investigated.Previous research mainly focused on the impact of storyline complexity on learners’oral performance,but the impact on learners’written performance is less investigated.Thus,this study aims at investigating the effects of narrative complexity of storyline on senior high school students’written performance,as displayed by its complexity,fluency,and accuracy.The present study has important pedagogical implications.That is,task design and assessment should make a distinction between different types of narrative tasks.For example,the task with single or dual storyline.Results on task complexity may contribute to informing the pedagogical choices made by teachers when prioritizing work with a specific linguistic dimension. 展开更多
关键词 storyline complexity narrative writing task complexity L2 writers
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累积复杂模型在2型糖尿病患者治疗负担中的应用及研究进展
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作者 李娟 马丽华 +2 位作者 杨芳 李琦 史玉洁 《华西医学》 2025年第8期1340-1345,共6页
2型糖尿病患者常面临较重的治疗负担,影响患者的生活质量与健康结局。减轻治疗负担是改善患者预后,提高治疗依从性的关键环节。该文基于累积复杂模型,系统剖析了2型糖尿病患者治疗负担的概念内涵与多维特征,探讨了累积复杂模型在2型糖... 2型糖尿病患者常面临较重的治疗负担,影响患者的生活质量与健康结局。减轻治疗负担是改善患者预后,提高治疗依从性的关键环节。该文基于累积复杂模型,系统剖析了2型糖尿病患者治疗负担的概念内涵与多维特征,探讨了累积复杂模型在2型糖尿病领域的理论拓展与应用价值,阐述了其在治疗负担研究中的具体应用进展,评估了现有工具的局限性并提出多维评估框架,最终提出基于累积复杂模型的干预措施,为优化以患者为中心的糖尿病管理方案提供了理论参照,也为治疗负担干预提供了新思路。 展开更多
关键词 累积复杂模型 2型糖尿病 治疗负担 综述
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2018—2022年我国9个城市83家医院门诊2型糖尿病降糖方案复杂性变化趋势
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作者 廖音 李丹丹 +2 位作者 程晟 李婧 李新刚 《中国医院用药评价与分析》 2025年第7期869-871,875,共4页
目的:探讨我国近年来门诊2型糖尿病患者降糖方案复杂性变化趋势,为保障患者依从性、优化降糖方案选择提供参考。方法:抽取2018—2022年我国9个城市83家医院2型糖尿病患者的门诊抗糖尿病药处方,对各类抗糖尿病药使用率、抗糖尿病药联合... 目的:探讨我国近年来门诊2型糖尿病患者降糖方案复杂性变化趋势,为保障患者依从性、优化降糖方案选择提供参考。方法:抽取2018—2022年我国9个城市83家医院2型糖尿病患者的门诊抗糖尿病药处方,对各类抗糖尿病药使用率、抗糖尿病药联合应用情况、固定剂量复方制剂使用情况以及降糖方案用药复杂性指数进行统计分析。结果:2018—2022年,新型口服降糖药二肽基肽酶4抑制剂、钠-葡萄糖耦联转运体2抑制剂、胰高血糖素样肽-1受体激动剂使用率明显升高;联合应用2种抗糖尿病药的患者所占比例有降低趋势,而联合应用4种及4种以上抗糖尿病药的患者所占比例明显升高(P<0.05);固定剂量复方制剂的使用率有升高趋势;患者使用抗糖尿病药的平均用药复杂性指数有明显降低趋势(P<0.05)。结论:临床医师及临床药师应关注糖尿病患者的降糖方案复杂性,以保障患者依从性及降糖效果。新型口服降糖药、固定剂量复方制剂使用较为方便,给临床降糖方案提供了更多选择,同时有助于减少降糖方案的复杂性,在具体使用中可根据患者的个体化需求选择。 展开更多
关键词 2型糖尿病 降糖方案 固定剂量复方制剂 用药复杂性指数
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Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2) 被引量:1
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作者 Laura A.Rishina Yury V.Kissin +3 位作者 Svetlana S.Lalayan Artem A.Antonov Vadim G.Krasheninnikov Alexander A.Gulin 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第4期492-500,共9页
The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. Th... The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2H5)2Cl and Mg(C4H9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2H5)2Cl-Mg(C4H9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution. 展开更多
关键词 Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure
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SiC/SiO_(2)复合涂层对碳纤维及其复合材料抗氧化性能影响研究 被引量:1
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作者 闫海波 陶佳栋 +3 位作者 周子涵 黄志雄 石敏先 丁杰 《复合材料科学与工程》 北大核心 2025年第3期130-138,共9页
采用溶胶-凝胶法和先驱体浸渍裂解法在碳纤维表面制备了一种SiC/SiO_(2)复合涂层,并使用热压罐工艺制备了碳纤维增强酚醛树脂基复合材料,测试了复合材料在600℃、800℃、1000℃下氧化后的弯曲强度,研究了涂层对碳纤维及其复合材料抗氧... 采用溶胶-凝胶法和先驱体浸渍裂解法在碳纤维表面制备了一种SiC/SiO_(2)复合涂层,并使用热压罐工艺制备了碳纤维增强酚醛树脂基复合材料,测试了复合材料在600℃、800℃、1000℃下氧化后的弯曲强度,研究了涂层对碳纤维及其复合材料抗氧化性能的影响。结果表明:经过在1000℃空气下的氧化,复合涂层碳纤维/酚醛树脂复合材料弯曲强度为60 MPa,是相同条件下的原始碳纤维/酚醛树脂复合材料弯曲强度的3.3倍,SiC/SiO_(2)涂层对碳纤维有较好的抗氧化效果且会使复合材料具备一定的弯曲强度。在SiC/SiO_(2)涂层的协同保护下,复合涂层碳纤维/酚醛树脂复合材料在氧乙炔火焰下表现出更好的耐烧蚀性能。 展开更多
关键词 SiC/SiO_(2)复合涂层 碳纤维 树脂基复合材料 抗氧化性能 弯曲性能 耐烧蚀性能
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半夏泻心汤合理中汤加减对中焦寒热错杂证2型糖尿病患者的临床疗效 被引量:1
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作者 孙敏 薛莎 +1 位作者 刘菊 戴朝博 《中成药》 北大核心 2025年第3期796-801,共6页
目的观察半夏泻心汤合理中汤加减对中焦寒热错杂证2型糖尿病患者的临床疗效。方法168例患者随机分为对照组和观察组,每组84例,对照组给予常规治疗,观察组在对照组基础上加用半夏泻心汤合理中汤加减,疗程12周。检测临床疗效、血糖达标率... 目的观察半夏泻心汤合理中汤加减对中焦寒热错杂证2型糖尿病患者的临床疗效。方法168例患者随机分为对照组和观察组,每组84例,对照组给予常规治疗,观察组在对照组基础上加用半夏泻心汤合理中汤加减,疗程12周。检测临床疗效、血糖达标率、降糖药物停减率、动态血糖参数(TIR、GVP、FPG-ARV、MAGE)、FPG、2 hPG、HbA1c、FINS、HOMA-β、HOMA-IR、lnISI、肠道菌群代谢产物(SCFAs、CA、DCA、CDCA、CA/CDCA)、中焦寒热错杂证评分、不良反应发生率变化。结果观察组显效率、总有效率、血糖达标率、降糖药物停减率高于对照组(P<0.05)。治疗后,2组TIR、FINS、HOMA-β、lnISI、SCFAs、CDCA升高(P<0.05),GVP、FPG-ARV、MAGE、FPG、2 hPG、HbA1c、HOMA-IR、CA、DCA、CA/CDCA、中焦寒热错杂证评分降低(P<0.05),以观察组更明显(P<0.05)。2组不良反应发生率比较,差异无统计学意义(P>0.05)。结论半夏泻心汤合理中汤加减可安全有效地改善中焦寒热错杂证2型糖尿病患者胰岛β细胞功能和胰岛素抵抗,提高胰岛素敏感指数和血糖达标率,减少血糖波动和降糖药物用量,调节肠道菌群代谢产物,影响糖代谢。 展开更多
关键词 半夏泻心汤 理中汤 常规治疗 2型糖尿病 中焦寒热错杂 血糖波动 SCFAs BAs
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深层煤岩气CO_(2)压裂工艺技术研究及应用 被引量:1
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作者 孙虎 陆灯云 +5 位作者 李泽锋 刘国良 张宏忠 兰建平 司晓冬 叶赛 《钻采工艺》 北大核心 2025年第3期139-146,共8页
中国深层煤岩气储层改造中仍面临着淡水消耗量大、复杂缝网难以形成、储层伤害大等难题,而CO_(2)压裂技术为解决这些难题提供了新思路。为了提高CO_(2)压裂技术在煤岩气储层改造中的适用性,开展了煤岩气藏CO_(2)压裂作用机理研究,开发了... 中国深层煤岩气储层改造中仍面临着淡水消耗量大、复杂缝网难以形成、储层伤害大等难题,而CO_(2)压裂技术为解决这些难题提供了新思路。为了提高CO_(2)压裂技术在煤岩气储层改造中的适用性,开展了煤岩气藏CO_(2)压裂作用机理研究,开发了CO_(2)压裂参数优化设计软件,改善了CO_(2)泡沫压裂液体系,并结合施工案例分析了CO_(2)压裂技术应用效果。理论研究和现场试验结果表明,研发的CO_(2)压裂优化设计软件计算效率提高50%;开发的CO_(2)泡沫压裂液体系泡沫半衰期达194 min,泡沫质量超75%,具有良好的耐温耐剪切性能和携砂性能;CO_(2)压裂作业后煤岩气储层形成了复杂缝网,导流能力优于常规水力压裂;CO_(2)前置压裂井平均试气产量比常规水力压裂井增产约15%;CO_(2)泡沫压裂井增产约18%,平均每口井节水50%以上。CO_(2)压裂技术实现了造复杂缝、增产、节水、减排的目的,在煤岩气绿色高效开发中具有广阔的应用前景。 展开更多
关键词 煤岩气 CO_(2)压裂 复杂缝网 增产 节约水资源
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Effects of axylitol-casein complex on insulin resistance and gut microbiota composition in high-fat-diet+streptozotocin-induced type 2 diabetes mellitus mice
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作者 Fanhua Kong Juan Zhang +5 位作者 Shimo Kang Xinyu Shen Aicheng Liu Yan Zheng Junhua Shao Xiqing Yue 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2741-2753,共13页
This study investigated the effects of a xylitol-casein non-covalent complex(XC)on parameters related to type 2 diabetes mellitus(T2DM),in addition to related changes in gut microbiome composition and functions.High-f... This study investigated the effects of a xylitol-casein non-covalent complex(XC)on parameters related to type 2 diabetes mellitus(T2DM),in addition to related changes in gut microbiome composition and functions.High-fat-diet(HFD)+streptozotocin(STZ)-induced T2DM mice were treated with xylitol(XY),casein(CN),and XC,after which fecal samples were collected for gut microbiota composition and diversity analyses based on 16S rRNA high-throughput sequencing and multivariate statistics.XC decreased body weight and improved glucose tolerance,insulin sensitivity,pancreas impairment,blood lipid levels,and liver function in T2DM mice compared to XY-and CN-treated mice.Furthermore,XC modulated theα-diversity,β-diversity and gut microbiota composition.Based on Spearman’s correlation analysis,the relative abundances of Alistipes,Bacteroides,and Faecalibaculum were positively correlated and those of Akkermansia,Lactobacillus,Bifidobacterium,and Turicibacter were negatively correlated with the phenotypes related to the improvement of T2DM.In conclusion,we found that XC alleviated insulin resistance by restoring the gut microbiota of T2DM mice.Our results provide strong evidence for the beneficial effects of XC on T2DM and motivation for further investigation in animal models and,eventually,human trials. 展开更多
关键词 Xylitol-casein complex Type 2 diabetes mellitus Insulin resistance Gut microbiota
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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration
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作者 Jin-Min Song Xin Jin +10 位作者 Zhong Luo Shu-Gen Liu Shao-Bo Liu Xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期806-822,共17页
Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional p... Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. 展开更多
关键词 Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications
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Genre Effect on L2 Syntactic Complexity and Holistic Rating for Writing Quality of Intermediate EFL Learners 被引量:2
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作者 Lili ZHANG Haitao LIU 《Chinese Journal of Applied Linguistics》 2021年第4期451-469,589,共20页
This exploratory study examines whether genre has an impact on syntactic complexity and holistic rating in EFL writing. Over 300 sample texts produced by intermediate learners were collected from a test and some regul... This exploratory study examines whether genre has an impact on syntactic complexity and holistic rating in EFL writing. Over 300 sample texts produced by intermediate learners were collected from a test and some regular after-class assignments for English writing courses. Each participant completed two writing tasks, one argumentative and the other narrative. Results show that genre type has a significant impact on L2 syntactic complexity. Genre effect is found stronger with timed writing tasks. L2 holistic ratings show correlation with syntactic complexity on the different measure(s) depending on genre type and planning conditions. Regression analyses reveal that for timed writing tasks, clausal density(clauses per sentence) is a reliable predictor for holistic assessment on intermediate EFL learners’ writing quality. It is found to account for 6% of the score variance for timed writing and 10% for timed argumentative writing. Genre is evidenced to be related to EFL writing holistic ratings. Closer examination indicates that while syntactic complexity is predictive of holistic writing scores for argumentative writing, it does not correlate with holistic scores for narrative writing. Other linguistic features rather than syntactic complexity may be accountable. Overall, the study lends support to genre effect in the relationship between syntactic complexity and L2 writing quality holistic rating. 展开更多
关键词 genre effect syntactic complexity L2 writing holistic rating intermediate learner
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基于香豆素-Cd^(2+)配合物的Cu^(2+)荧光探针构建及其应用
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作者 肖嘉扬 朱鑫玥 +5 位作者 郭小云 杨帆 杨泰然 陈蕊 高云 高妍 《发光学报》 北大核心 2025年第8期1526-1535,共10页
以香豆素醛和芘腙为原料经缩合反应合成了配体ABX,它分别对Cd^(2+)和Cu^(2+)有着完全不同的紫外和荧光响应。竞争实验表明,若有Cu^(2+)的存在则会对探针识别Cd^(2+)造成干扰,Cu^(2+)会与ABX-Cd^(2+)发生置换反应生成更为稳定的ABX-Cu^(... 以香豆素醛和芘腙为原料经缩合反应合成了配体ABX,它分别对Cd^(2+)和Cu^(2+)有着完全不同的紫外和荧光响应。竞争实验表明,若有Cu^(2+)的存在则会对探针识别Cd^(2+)造成干扰,Cu^(2+)会与ABX-Cd^(2+)发生置换反应生成更为稳定的ABX-Cu^(2+)配合物。因此,着重考察了ABX与Cd^(2+)络合生成的ABX-Cd^(2+)对Cu^(2+)的识别性能。结果表明,探针ABX-Cd^(2+)可高选择、高灵敏度识别Cu^(2+),荧光响应效率可由ABX直接识别Cu^(2+)的68.71%显著提升至96.25%。紫外光下负载探针ABX-Cd^(2+)的“试纸”呈橙红色,再浸入不同浓度的Cu^(2+)后荧光逐渐猝灭,从而成功应用于对自来水和工业废水中Cu^(2+)的半定量检测;此外,在紫外灯照射下用ABX溶液在硅胶板上书写的黄绿色字母经涂Cd^(2+)后变橙红色,然后进一步涂Cu^(2+)后荧光猝灭,该识别效果适于应用在加密防伪油墨领域。探针ABX-Cd^(2+)也被应用于细胞内对Cu^(2+)的生物成像研究。 展开更多
关键词 荧光探针 香豆素 Cd^(2+)配合物 Cu^(2+) 工业废水 荧光防伪 生物成像
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基于热-流-固耦合的CO_(2)多级压裂增强型地热系统取热数值模拟
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作者 王高升 周一凡 +6 位作者 赵佳琳 宋先知 黄中伟 易俊琳 李爽 夏毫宾 郑铖铖 《华南师范大学学报(自然科学版)》 北大核心 2025年第2期1-11,共11页
在考虑裂缝内非达西渗流和局部非热平衡传热(LTNE)的基础上,构建了CO_(2)多级压裂EGS热-流-固耦合模型,并分析了复杂裂缝网络内渗流传热机制;对比不同裂缝网络条件下CO_(2)的多级压裂EGS取热效果,揭示了主裂缝、次级裂缝和天然裂缝在EG... 在考虑裂缝内非达西渗流和局部非热平衡传热(LTNE)的基础上,构建了CO_(2)多级压裂EGS热-流-固耦合模型,并分析了复杂裂缝网络内渗流传热机制;对比不同裂缝网络条件下CO_(2)的多级压裂EGS取热效果,揭示了主裂缝、次级裂缝和天然裂缝在EGS取热过程中作用机制,研究了主裂缝条数、主裂缝开度、次级裂缝水平长度和天然裂缝渗透率等关键裂缝参数对EGS取热效果影响规律。结果表明:裂缝网络中存在非达西渗流,特别是在主裂缝中尤为显著。与只考虑主裂缝和天然裂缝的算例相比,进一步考虑次级裂缝后,其累积能量增加80.36%;在忽略主裂缝和次级裂缝后,其累积能量减少64.58%,说明人工裂缝网络对强化取热具有重要的影响。此外,主裂缝条数对取热效果影响最显著,当次级裂缝直接相交时累积能量达到最高。该研究有望为EGS复杂裂缝网络优化研究提供重要参考。 展开更多
关键词 干热岩 增强型地热系统 二氧化碳 多级压裂 复杂裂缝网络 裂缝参数评价
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系列羰基铼配合物光催化活化CO_(2)机理
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作者 臧杰超 朝鲁门 +4 位作者 肖锟 李明飞 张雯 罗会亮 慈成刚 《环境化学》 北大核心 2025年第9期2460-2470,共11页
二亚胺羰基铼配合物兼具光敏剂和催化剂双功能,在CO_(2)光还原领域吸引了广泛关注.红外光谱、紫外-可见光谱和磷光发射光谱作为重要手段,在探索CO_(2)光还原机理和调控产物量子产率等方面扮演了重要角色.使用密度泛函理论(DFT)和含时密... 二亚胺羰基铼配合物兼具光敏剂和催化剂双功能,在CO_(2)光还原领域吸引了广泛关注.红外光谱、紫外-可见光谱和磷光发射光谱作为重要手段,在探索CO_(2)光还原机理和调控产物量子产率等方面扮演了重要角色.使用密度泛函理论(DFT)和含时密度泛函理论(TDDFT)方法对实验合成的6种二亚胺羰基铼配合物[Re(5-R-phen)(CO)_(3)(X)]^(0/+),phen=1,10-邻菲啰啉,R=H(Re1),O(Re2),CN(Re3),COOH(Re4),CONH_(2),X=Cl或吡啶(当R=CONH_(2),X=Cl,标记为Re5,X=吡啶,标记为Re6)的电子结构、红外光谱、紫外-可见吸收光谱、磷光发射光谱、CO_(2)吸附和活化过程进行计算,并基于计算结果设计了3种配合物.结果显示金属中心的吸电子配体,降低了中心金属电荷密度,不利于CO_(2)配位.二亚胺羰基配体的供电子基团能够增加金属中心电荷密度,有利于CO_(2)配位,并导致吸收峰向可见光区移动,有利于可见光的利用. 展开更多
关键词 二亚胺羰基铼配合物 红外光谱 紫外-可见光谱 磷光发射光谱 CO_(2) 光还原 密度泛函 理论
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电化学介导胺再生CO_(2)捕集技术研究进展
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作者 毛元豪 范会峰 +5 位作者 SAYD Sultan 方芙蓉 钟琦 余云松 吴小梅 张早校 《化工进展》 北大核心 2025年第7期4089-4100,共12页
随着全球气候变化问题的日益严重,降低大气中的二氧化碳(CO_(2))浓度已成为急需解决的重要问题。然而,现今最具应用潜力的有机胺化学吸收工艺的大范围推广仍受到高能耗问题的阻碍。以电化学介导胺再生CO_(2)捕集技术为代表的电化学碳捕... 随着全球气候变化问题的日益严重,降低大气中的二氧化碳(CO_(2))浓度已成为急需解决的重要问题。然而,现今最具应用潜力的有机胺化学吸收工艺的大范围推广仍受到高能耗问题的阻碍。以电化学介导胺再生CO_(2)捕集技术为代表的电化学碳捕集技术避免了高温蒸汽的使用,具有灵活、高效的特点,为低能耗碳捕集技术的发展开辟了新路径。本文介绍了电化学介导胺CO_(2)捕集技术在反应体系选择、系统模拟计算和高效反应器设计方面的最新进展,分析其研究现状并指出其发展方向。随后进一步分析了电化学体系与碳捕集、利用与封存(CCUS)技术领域更广泛交叉应用的潜力,提出电化学CO_(2)压缩机、电化学碳捕集还原一体化工艺流程。本综述将为推动电力驱动的低能耗碳捕集技术的研究和发展提供新的发展方向与策略。 展开更多
关键词 电化学介导胺再生 碳捕集 铜-胺配合物 反应器 电化学压缩机 CO_(2)电还原
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A Comparative Analysis of Syntactic Complexity in Applied Linguistics Abstracts Written by Chinese Novice Writers and Native English Advanced Writers
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作者 Mingming Zhao Tianshuang Ge 《Open Journal of Applied Sciences》 2024年第1期1-26,共26页
The rhetorical structure of abstracts has been a widely discussed topic, as it can greatly enhance the abstract writing skills of second-language writers. This study aims to provide guidance on the syntactic features ... The rhetorical structure of abstracts has been a widely discussed topic, as it can greatly enhance the abstract writing skills of second-language writers. This study aims to provide guidance on the syntactic features that L2 learners can employ, as well as suggest which features they should focus on in English academic writing. To achieve this, all samples were analyzed for rhetorical moves using Hyland’s five-rhetorical move model. Additionally, all sentences were evaluated for syntactic complexity, considering measures such as global, clausal and phrasal complexity. The findings reveal that expert writers exhibit a more balanced use of syntactic complexity across moves, effectively fulfilling the rhetorical objectives of abstracts. On the other hand, MA students tend to rely excessively on embedded structures and dependent clauses in an attempt to increase complexity. The implications of these findings for academic writing research, pedagogy, and assessment are thoroughly discussed. 展开更多
关键词 Syntactic complexity Rhetorical Functions Research Article Abstract L2 Academic Writing
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