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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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Star-shaped Block Copolymers of Poly-2-alkyl-5,6-dihydrooxazines:Synthesis,Conformational Characteristics,Thermoresponsiveness and Complexation with Curcumin
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作者 Tatyana U.Kirila Serafim V.Rodchenko +2 位作者 Nina D.Kozina Andrey V.Tenkovtsev Alexander P.Filippov 《Chinese Journal of Polymer Science》 2026年第2期423-436,I0012,共15页
Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cat... Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cationic ring-opening polymerization.The ratio of blocks,the order of their attachment to the core,and arm length were varied.Conformation of synthesized stars was determined by methods of molecular hydrodynamics and optics.It has been shown that star-shaped molecules were characterized by high intramolecular density,and the arm folding increased with their lengthening.The influence of the structure of block copolymers and their molar mass on the critical micelle concentration has been established.Complexes of synthesized star-shaped block copolymers with curcumin were obtained and the efficient binding of curcumin to polymer molecules was demonstrated.The behavior of the aqueous solutions of the prepared polymer stars and their complexes with curcumin was investigated by light scattering and turbidimetry methods.The influence of the structure and molar mass of star polymers on their thermoresponsiveness and the phase separation temperatures in aqueous solutions was analyzed.A slight increase in the phase separation temperature was found on passage from polymer solutions to solutions of polymer complexes with hydrophobic curcumin. 展开更多
关键词 Thermoresponsive star-shaped polymers Block copolymer of poly-2-alkyl-5 6-dihydrooxazine Aqueous solutions complex of polymer with curcumin Phase separation
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Combinational Inhibition of the eIF4F Complex,AKT1,and EZH2 Enhances Anticancer Effects in BRAFV600E Mutant A375 Melanoma Cells
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作者 Yuanxin Miao Fengyun Hao Sae Hwi Ki 《Oncology Research》 2026年第3期502-522,共21页
Objectives:The eukaryotic initiation factor 4F(eIF4F)translation initiation complex inhibitors(eIF4Fi)were recently found to hyperactivate extracellular signal-regulated kinases 1/2(ERK1/2)signals,which contribute to ... Objectives:The eukaryotic initiation factor 4F(eIF4F)translation initiation complex inhibitors(eIF4Fi)were recently found to hyperactivate extracellular signal-regulated kinases 1/2(ERK1/2)signals,which contribute to acquired resistance to BRAF(B-Raf proto-oncogene,serine/threonine kinase)inhibitors in melanoma.This present study aims to elucidate how to overcome the resistance of the eIF4Fi in BRAFV600E mutant melanoma cells and explore the underlying mechanisms.Methods:Melanoma A375(vemurafenib[VEM]-sensitive)and A375R(VEM-resistant)cells were exposed to eIF4Fi RocA at varying doses and durations in vitro.We investigated the impact of RocA on the activity of ERK1/2,AKT serine/threonine kinase 1(AKT1),eIF4E,and enhancer of zeste homolog 2(EZH2).We then examined the impact of RocA on pro-apoptotic BH3-only proteins and proliferative proteins.We subsequently determined the effect of combined eIF4Fi,AKT1 inhibitor,EZH2 inhibitor or VEM on tumor growth in vitro and in vivo.Results:RocA inhibited proliferation and induced apoptosis in A375 cells,but inhibited proliferation in A375R cells.RocA rapidly reactivated ERK1/2 at 3 h and returned to baseline levels at 48 h.However,eIF4E and AKT1 activation began at 12 h and peaked at 48 h.ERK1/2 positively regulated EZH2 and EZH2-dependent expression of c-Fos and EGR1,while AKT1 negatively regulated c-Myc,c-Jun,and BMF,but positively regulated eIF4E.RocA downregulated ERK1/2(or EZH2,AKT1,and eIF4E)independent bcl-2 and Mcl-1 expression.AKT1i enhanced RocA-induced cell apoptosis,while EZH2i reduced RocA-induced cell proliferation.Combined CR-1-31-B,EZH2i,and AKT1i effectively overcame resistance to RocA and VEM resistance both in vitro and in vivo.Conclusion:The eIF4F complex inhibitor reactivates ERK1/2-EZH2 and AKT1 signaling pathways,resulting in resistance to both eIF4Fi and VEM.Combined administration of an eIF4Fi with EZH2 and AKT1 inhibitors effectively enhances sensitivity to both eIF4F complex and BRAF inhibitors. 展开更多
关键词 Melanoma B-raf proto-oncogene serine/threonine kinase-inhibitor eukaryotic initiation factor 4F complex inhibitor extracellular signal-regulated kinases 1/2 enhancer of zeste homolog 2 AKT serine/threonine kinase 1 Bcl-2 modifying factor
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TRAPPC2基因变异致X-连锁迟发性脊椎骨骺发育不良的3个家系分析
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作者 王亚琼 应令雯 +5 位作者 陈瑶 姚如恩 娄丹 卢亚亚 李娟 王秀敏 《检验医学》 2026年第2期133-143,共11页
目的探讨转运蛋白复合体亚单位2(TRAPPC2)基因变异致X-连锁迟发性脊椎骨骺发育不良(SEDT)家系的临床表型和遗传学特点。方法选取2019年1月—2024年9月上海交通大学医学院附属上海儿童医学中心确诊的3个X-连锁SEDT家系。收集家系成员的... 目的探讨转运蛋白复合体亚单位2(TRAPPC2)基因变异致X-连锁迟发性脊椎骨骺发育不良(SEDT)家系的临床表型和遗传学特点。方法选取2019年1月—2024年9月上海交通大学医学院附属上海儿童医学中心确诊的3个X-连锁SEDT家系。收集家系成员的临床资料,并进行全外显子组测序(WES)和生物信息学分析,采用Sanger测序对可疑突变进行验证。参照美国医学遗传学与基因组学学会(ACMG)相关指南对变异进行评级。结果3个家系的先证者均为男性,均因生长迟缓就诊,脊柱X线片示椎体扁平、前部上下缘凹陷、中后部呈驼峰样突起改变。家系1和家系2的先证者TRAPPC2基因(NM_001011658.4)均存在半合子变异c.271_275del(p.Gln91Argfs*9),为致病性变异;先证者母亲该位点均存在杂合突变,父亲未检测到该突变。家系3先证者TRAPPC2基因(NM_001011658.4)存在半合子变异c.191_192delTG(p.Val64Glyfs*24),其父母未发现该位点存在任何突变,考虑为假定新发变异;行重组人生长激素(rhGH)治疗,疗效欠佳。结论TRAPPC2基因变异所致的SEDT呈晚发性、进行性特征,可致不成比例的身材矮小和关节过早退化。对于青少年时期起病的患儿,若合并上下部量异常或指尖距不匹配,需警惕SEDT。WES检测有助于明确病因。 展开更多
关键词 转运蛋白复合体亚单位2基因 缺失突变 X-连锁迟发性脊椎骨骺发育不良
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强力益气颗粒对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的作用及机制研究
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作者 陈建 李慧凛 +4 位作者 应汝炯 董云 沈洁 吴丽琳 盛昭园 《环球中医药》 2026年第1期27-35,共9页
目的通过观察强力益气颗粒对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的作用,探讨骨骼肌糖代谢信号途径中介复合体13/核受体4家族成员2/葡萄糖转运蛋白-4(mediator complex13/nuclear receptor family 4 member-2/glucose transporter-4,MED... 目的通过观察强力益气颗粒对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的作用,探讨骨骼肌糖代谢信号途径中介复合体13/核受体4家族成员2/葡萄糖转运蛋白-4(mediator complex13/nuclear receptor family 4 member-2/glucose transporter-4,MED13/Nurr1/GLUT-4)在重症肌无力中的可能的作用机制。方法将鼠L6骨骼肌成肌细胞分离培育好后,分为正常血清组、模型组、空白血清组和强力益气含药血清高、中、低剂量组共6组。除正常血清组外,其余各组均使用H_(2)O_(2)造成氧化损伤,正常血清组与模型组分别换液加入FBS完全培养基培育;空白血清组换液加入正常大鼠血清培育(排除PBS对细胞的影响),强力益气含药血清高、中、低剂量组分别换液加入相应剂量组的大鼠含药血清培育,培养24小时后收集细胞。应用细胞增殖检测、流式凋亡周期检测;分别应用Real-time PCR、免疫荧光、Western blot检测法,检测强力益气血清对L6骨骼肌成肌细PGC-1α、MEF2、MED13、Nurr1、GLUT-4蛋白质定量、定位、定性的表达。结果H_(2)O_(2)处理2小时对L6大鼠肌细胞的增殖有显著的抑制作用(P<0.05),凋亡率显著上升(P<0.05),强力益气颗粒含药血清能够提高H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞的增殖率,降低凋亡率。能使MED13基因在转录水平、基因在蛋白水平上出现明显的上调(P<0.05);对于Nurr1基因则是相对模型组降低了其转录水平(P<0.05);对于PGC-1α、MEF2以及GLUT-4,H_(2)O_(2)处理都显著降低了它们的转录水平(P<0.05),含药血清的预处理能够一定程度上逆转这种降低(P<0.05),同时呈现出一定程度上的剂量依赖性。结论强力益气颗粒含药血清通过提高MED13、GLUT-4、PGC-1α、MEF2基因蛋白水平的表达,并且降低Nurr1基因蛋白水平的表达,对H_(2)O_(2)损伤大鼠L6骨骼肌成肌细胞具有保护作用,从而得出强力益气颗粒含药血清通过干预MED13/Nurr1/GLUT4信号通路,能改善骨骼肌糖代谢,减少骨骼肌细胞损伤,进而改善重症肌无力骨骼肌功能受损的病理状态。 展开更多
关键词 重症肌无力 大鼠L6骨骼肌成肌细胞 强力益气颗粒 骨骼肌糖代谢 中介复合体13/核受体4家族成员2/葡萄糖转运蛋白-4信号途径
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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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Hydrogenation of CO_(2) to formate catalyzed by N⁃heterocyclic carbene⁃nitrogen⁃phosphine chelated iridium(Ⅰ)complexes
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作者 GONG Huihua CUI Tianhua +6 位作者 JI Li ZHANG Jichuan ZHANG Liyuan CHEN Yan WANG Zhenye XU Jiaqi LI Ruixiang 《无机化学学报》 北大核心 2025年第12期2609-2620,共12页
To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)... To achieve efficient catalytic hydrogenation of CO_(2)to formate,we employed a transmetallation strategy to develop three novel iridium(Ⅰ)complexes,which feature N‑heterocyclic carbene‑nitrogen‑phosphine ligands(CNP)and a 1,5‑cyclooctadiene(cod)molecule:[Ir(cod)(κ^(3)‑CN^(im)P)]Cl(1⁃Cl),[Ir(cod)(κ^(3)‑CN^(im)P)]PF6(1⁃PF_(6)),and[Ir(cod)(κ^(3)‑CNHP)]Cl(2).The^(1)H NMR spectra,^(31)P NMR spectra,and high‑resolution mass spectra verify the successful synthesis of these three Ir(Ⅰ)‑CNP complexes.Furthermore,single‑crystal X‑ray diffraction analysis confirms the coordination geometry of 1⁃PF_(6).The strong Ir—C(NHC)bond suggests that the carbene carbon plays an enhanced anchoring role to iridium due to its strongσ‑donating ability,which helps stabilize the active metal species during CO_(2)hydrogenation.As a result,the Ir(Ⅰ)‑CNP complex exhibits remarkable activity and long catalytic lifetime for the hydrogenation of CO_(2)to formate,reaching a turnover number(TON)of 1.16×10^(6)after 150 h at a high temperature of 170℃,which was a relatively high value among all the Ir complexes.CCDC:2384071,1⁃PF_(6). 展开更多
关键词 CO_(2)hydrogenation iridium complex CNP ligands homogeneous catalysis
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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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Numerical investigations on T_(1)-T_(2)^(*)-based petrophysical evaluation in shale oil reservoir with complex minerals
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作者 Ji-Long Liu Ran-Hong Xie +5 位作者 Jiang-Feng Guo Chen-Yu Xu Guo-Wen Jin Xiang-Yu Wang Bo-Chuan Jin Xiao-Long Ju 《Petroleum Science》 2025年第11期4538-4554,共17页
It is of great significance to evaluate the petrophysical properties in shale oil reservoir,which can contribute to geological storage CO_(2).Two-dimensional nuclear magnetic resonance(2D NMR)technology has been appli... It is of great significance to evaluate the petrophysical properties in shale oil reservoir,which can contribute to geological storage CO_(2).Two-dimensional nuclear magnetic resonance(2D NMR)technology has been applied to petrophysical characterization in shale oil reservoir.However,limitations of traditional 2D NMR(T_(1)-T_(2)or T_(2)-D)in detecting short-lived organic matter and the complexity of mineral compositions,pose NMR-based petrophysical challenges.The organic pores were assumed saturated oil and the inorganic pores were assumed saturated water,and the numerical algorithm and theory of T_(1)-T_(2)^(*)in shale oil reservoir were proposed,whose accuracy was validated through T_(2),T_(1)-T_(2)and T_(2)^(*)experiments.The effects of mineral types and contents on the T_(1)-T_(2)^(*)responses were firstly simulated by the random walk algorithm,revealing the NMR response mechanisms in shale oil reservoir with complex mineral compositions at different magnetic field frequency(f).The results indicate that when the pyrite content is 5.43%,dwell time is 4μs,the f is 200 MHz,and echo spacing is 0.4 ms,the T_(1)-T_(2)^(*)-based porosity is 2.39 times that of T_(1)-T_(2)-based porosity.The T_(2LM)^(*)is 0.015 ms,which is 0.015 times that of T_(2)LM.The T_(1LM)is 8.84 ms,which is 0.63 times that of T_(1LM).The T_(1)-T_(2)^(*)-based petrophysical conversion models were firstly created,and the foundation of petrophysical conversion was laid at different f. 展开更多
关键词 Shale oil complex minerals T_(1)-T_(2)^(*) Petrophysical parameters Frequency conversion
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脑脊液AP2与阿尔茨海默病病理及认知功能的相关性研究
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作者 李仁贵 陈雨豪 +5 位作者 盛泽虎 冉明 王静怡 陈茗 汪克建 余维华 《阿尔茨海默病及相关病杂志》 2026年第1期10-18,共9页
目的:探讨阿尔茨海默病(AD)患者脑脊液(CSF)中衔接蛋白复合物2(AP2)的水平与AD病理、脑结构变化及认知功能的关联。方法:本研究纳入了来自AD神经影像学倡议数据库的138例AD患者、403例轻度认知障碍患者(MCI)和167名认知功能正常者(CN),... 目的:探讨阿尔茨海默病(AD)患者脑脊液(CSF)中衔接蛋白复合物2(AP2)的水平与AD病理、脑结构变化及认知功能的关联。方法:本研究纳入了来自AD神经影像学倡议数据库的138例AD患者、403例轻度认知障碍患者(MCI)和167名认知功能正常者(CN),测量其CSF中AP2(α2和β1亚基)水平;收集基线及五年随访期间的AD核心生物标志物浓度,数据包括β-淀粉样蛋白1-42(Aβ_(42))、总tau蛋白(t-Tau)和磷酸化tau蛋白(p-Tau181);脑结构数据包括脑室体积、海马体积和内嗅皮层厚度;认知功能评分数据包括简易智力状态检查量表(MMSE)、临床痴呆评分总和量表(CDRSB)。采用单因素协方差分析、多元线性回归模型和线性混合效应模型进行统计分析。结果:在基线时,CSF中AP2水平在CN组、MCI组和AD组间无显著差异,但在载脂蛋白(APOE)ε4携带者中均显著升高。随着年龄的增长,CSF中AP2水平呈上升趋势,与AD病理进展一致。CSF中AP2水平升高与CSF Aβ_(42)、t-Tau、p-Tau181浓度升高以及脑室体积更小呈显著相关,尤其在CN、MCI阶段更为显著。CSF AP2β1与CDRSB呈负相关,与海马体积和内嗅皮层厚度呈正相关。此外,CSF中AP2影响纵向脑结构及认知的改变,尤其在非AD组中更为显著。结论:CSF中AP2可能参与早期Aβ和Tau病理,并与脑室体积、海马体积、内嗅皮层厚度和认知的改变密切相关,尤其在AD的前临床和前驱阶段。 展开更多
关键词 阿尔茨海默病 衔接蛋白复合物2 Tau病理 网格蛋白 内吞作用
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复杂小断块油藏CO_(2)异步注采实验及技术政策优化
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作者 凌定坤 蒋庞露 +3 位作者 王智林 陈龙兴 杨睿 陆佳昊 《复杂油气藏》 2026年第1期17-23,共7页
针对复杂断块油藏受限于含油面积及形态,常规气驱方式难以实现有效波及动用的难题,提出了CO_(2)异步注采驱替方式以提升其波及效果及最终采收率。首先通过研发复杂断块油藏物理模型,对比了其与常规岩心模型下不同驱替方式的采收率,明确... 针对复杂断块油藏受限于含油面积及形态,常规气驱方式难以实现有效波及动用的难题,提出了CO_(2)异步注采驱替方式以提升其波及效果及最终采收率。首先通过研发复杂断块油藏物理模型,对比了其与常规岩心模型下不同驱替方式的采收率,明确了异步注采提升复杂断块油藏采收率幅度及其原因,且确定了该驱替方式下最佳注入压力和注入量。其次,基于Q4断块真实模型进行数值模拟研究,优化了在异步注采方式下的注气井网、注气量、注气速度、焖井时间等技术参数。结果表明:异步注采驱替方式通过动用常规气驱未动用的“角隅油”,可提高复杂断块油藏采收率11.09个百分点;注气速度对最终采收率影响较大,最佳注气速度为3.96PV/a;注入量及焖井时间对最终采收率有一定影响,最佳注入量及焖井时间分别为1.5PV和30d;在以上参数条件下可实现Q4断块换油率提高至0.39,采收率为22.36%。研究结果为复杂小断块油藏采收率的大幅提升提供新的技术手段及参考借鉴。 展开更多
关键词 复杂断块油藏 角隅油 CO_(2)驱 异步注采 换油率 采收率
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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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ZMIZ2/MCM3 Axis Participates in Triple-Negative Breast Cancer Progression
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作者 Xiaopan Zou Meiyang Sun +3 位作者 Xin Jiang Jingze Yu Xiaomeng Li Bingyu Nie 《Oncology Research》 2026年第1期297-324,共28页
Objective:Triple-negative breast cancer(TNBC)is highly aggressive and lacks an effective targeted therapy.This study aimed to elucidate the functions and possible mechanisms of action of zinc finger miz-type containin... Objective:Triple-negative breast cancer(TNBC)is highly aggressive and lacks an effective targeted therapy.This study aimed to elucidate the functions and possible mechanisms of action of zinc finger miz-type containing 2(ZMIZ2)and minichromosome maintenance complex component 3(MCM3)in TNBC progression.Methods:The relationship between ZMIZ2 expression and clinical characteristics of TNBC was investigated.In vitro and in vivo experiments were performed to investigate the role of ZMIZ2 dysregulation in TNBC cell malignant behaviors.The regulatory relationship between ZMIZ2 and MCM3 was also explored.Transcriptome sequencing was performed to elucidate possible mechanisms underlying the ZMIZ2/MCM3 axis in TNBC.Results:High ZMIZ2 expression levels were associated with the malignant degree of TNBC.ZMIZ2 overexpression promoted TNBC cell proliferation,migration,and invasion;inhibited apoptosis;and induced G1 phase cell cycle arrest,whereas knockdown of ZMIZ2 had the opposite effect.ZMIZ2 directly targeted and positively regulated MCM3 expression.MCM3 knockdown reversed the effect of ZMIZ2 overexpression on TNBC tumor growth both in vitro and in vivo.High MCM3 expression levels were linked to the degree of malignancy and poor prognosis in TNBC.The differentially expressed genes associated with the ZMIZ2/MCM3 axis were significantly enriched in multiple pathways,such as the mitogen-activated protein kinase(MAPK),mechanistic target of rapamycin(mTOR),Wnt,and Ras signaling pathways,as verified by The Cancer Genome Atlas data.Conclusions:ZMIZ2 and MCM3 were highly expressed in TNBC.ZMIZ2 promoted the development by positively regulating MCM3 expression.Key pathways,such as the Ras/MAPK,phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mTOR,and Wnt signaling pathways,may be key downstreammechanisms. 展开更多
关键词 Triple-negative breast cancer zinc finger miz-type containing 2 minichromosome maintenance complex component 3 pathway enrichment analysis
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SDHA Deficiency in Hepatocellular Carcinoma Promotes Tumor Progression through Succinate-Induced M2 Macrophage Polarization
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作者 Xinyang Li Luyuan Ma +7 位作者 Chuan Shen Ruolan Gu Shilong Dong Mingjie Liu Ying Xiao Wenpeng Liu Yuexia Liu Caiyan Zhao 《Oncology Research》 2026年第2期592-617,共26页
Background:Hepatocellular carcinoma(HCC)is an aggressive and lethal malignancy.Metabolic reprogramming dynamically remodels the tumor microenvironment(TME)and drives HCC progression.This study investigated the mechani... Background:Hepatocellular carcinoma(HCC)is an aggressive and lethal malignancy.Metabolic reprogramming dynamically remodels the tumor microenvironment(TME)and drives HCC progression.This study investigated the mechanism through which metabolic reprogramming remodels the TME in HCC.Methods:HCC patient transcriptome data were subjected to bioinformatics analysis to identify differentially expressed genes and immune infiltration status.Immunohistochemical analysis was performed to determine the correlation between succinate dehydrogenase complex subunit A(SDHA)expression and M2 macrophage infiltration.SDHA-knockdown or SDHA-overexpressing HCC cells were used for in vitro experiments,including co-culturing,flow cytometry,and enzyme-linked immunosorbent assay.Western blotting assay,functional assays,and subcutaneous tumor model mice were used to elucidate the molecular mechanisms underlying succinate-mediated HCC cell-macrophage interactions in the TME.Results:Higher infiltration of M2 macrophages correlated with worse prognosis in HCC patients.SDHA was downregulated in HCC tumor tissues and showed a negative correlation with M2 macrophage infiltration.SDHA knockdown promoted M2 macrophage polarization,whereas SDHA overexpression reversed this effect.Mechanistically,SDHA deficiency in HCC cells induced succinate accumulation,which promoted M2 macrophage polarization by activating the G protein-coupled receptor 91(GPR91)/signal transducer and activator of transcription 3(STAT3)pathway.Concurrently,succinate stimulation enhanced mitochondrial oxidative phosphorylation in M2 macrophages,thereby promoting HCC progression.Serum succinate levels were elevated in HCC patients.The receiver operating characteristic curve analysis indicated that serum succinate is a promising diagnostic marker for HCC(area under the curve=0.815).Conclusion:SDHA deficiency leads to succinate accumulation,which promotes M2 macrophage polarization through the GPR91/STAT3 pathway,thereby facilitating HCC progression.Based on these findings,serum succinate could be a promising diagnostic biomarker for HCC. 展开更多
关键词 Hepatocellular carcinoma metabolic reprogramming tumor microenvironment SUCCINATE M2 macrophage succinate dehydrogenase complex subunit A(SDHA) G protein-coupled receptor 91(GPR91)
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急性ST段抬高型心肌梗死患者心电碎裂QRS波与血清sST2蛋白的诊断价值
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作者 倪云杰 李小燕 +3 位作者 何晓兰 张华 胡炜律 辛沙 《中国急救医学》 2026年第1期36-40,共5页
目的探讨急性ST段抬高型心肌梗死患者碎裂QRS波(fQRS)与可溶性生长刺激表达基因2蛋白(sST2)的诊断价值。方法选择2023年1月至2024年10月杭州市富阳区第一人民医院收治的178例急性ST段抬高型心肌梗死患者为观察组,另选医院同期收治的186... 目的探讨急性ST段抬高型心肌梗死患者碎裂QRS波(fQRS)与可溶性生长刺激表达基因2蛋白(sST2)的诊断价值。方法选择2023年1月至2024年10月杭州市富阳区第一人民医院收治的178例急性ST段抬高型心肌梗死患者为观察组,另选医院同期收治的186例心肌炎患者为常规组,入组后检测两组心电图fQRS和sST2水平,收集两组的一般资料(年龄、性别、体重指数、高血压、吸烟、基础疾病等),以多因素Logistic回归分析急性ST段抬高型心肌梗死的影响因素,绘制受试者工作特征(ROC)曲线,以曲线下面积(AUC)评估心电图fQRS和sST2及二者联合对急性ST段抬高型心肌梗死的诊断价值。结果观察组心电图fQRS和sST2水平高于常规组(P<0.05),年龄、中性粒细胞与淋巴细胞比值(NLR)、修正休克指数(MSI)、中性粒细胞与高密度脂蛋白胆固醇比值(NHR)、发病到入院时间、入院时急性冠脉事件全球注册(GRACE)评分高于常规组(P<0.05);多因素Logistic分析结果显示,NLR、MSI、fQRS和sST2为急性ST段抬高型心肌梗死的危险因素(P<0.05);ROC曲线结果显示,心电图fQRS和sST2及二者联合预测急性ST段抬高型心肌梗死发生的AUC分别为0.722、0.725、0.797(P<0.05)。结论心电图fQRS和sST2可用于预测急性ST段抬高型心肌梗死的发生,且二者联合的诊断价值更高。 展开更多
关键词 心电碎裂QRS波 急性ST段抬高型心肌梗死 可溶性生长刺激表达基因2蛋白 诊断价值
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多重周期二元序列的联合k错2-adic复杂度 被引量:4
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作者 董丽华 胡予濮 曾勇 《计算机学报》 EI CSCD 北大核心 2009年第6期1134-1139,共6页
具有较强密码学性质的序列应该具有较大的2-adic复杂度,以抗击已知的带进位操作反馈移位寄存器综合算法,同时改变较少的几项也不应引起序列的2-adic复杂度的急剧减小,即k错2-adic复杂度也应尽可能地大.近来,向量化流密码的设计逐渐成为... 具有较强密码学性质的序列应该具有较大的2-adic复杂度,以抗击已知的带进位操作反馈移位寄存器综合算法,同时改变较少的几项也不应引起序列的2-adic复杂度的急剧减小,即k错2-adic复杂度也应尽可能地大.近来,向量化流密码的设计逐渐成为国内外密码学界关注的一个重要方向.对这种类型的流密码的安全性分析需要研究多重序列-有限多个序列的并行流的复杂度.目前对多重序列的复杂度研究多集中于线性复杂度.基于此,文中首先给出了多重二元序列的联合k错2-adic复杂度的定义.随后,借助数论中的中国剩余定理等相关理论给出了联合k错2-adic复杂度的下界,并讨论了具有最大联合2-adic复杂度以及较大联合k错2-adic复杂度的N周期序列的存在性及具有此种性质的序列的数目下界.以此种周期序列作为密钥流序列可以有效抵抗穷举攻击. 展开更多
关键词 密码学 流密码 FCSR 联合2-adic复杂度 k错2-adic复杂度
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周期序列2-adic复杂度的稳定性 被引量:5
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作者 王磊 蔡勉 肖国镇 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2000年第3期348-350,共3页
提出了周期序列 2 adic复杂度的稳定性问题 ,分析了其现实意义 ,定义了k 错 2 adic复杂度并简单讨论了其性质 ,最后在周期序列 2 adic复杂度分布基础上给出了两类稳定性较好的序列 .
关键词 周期序列 2-adic复杂度 稳定性 保密通信
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