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Prediction of High Critical Temperature Superconductors in Ternary Y-Hf-H System under High Pressure
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作者 Chao Deng Min Wang +5 位作者 Siqi Guo Hongyu Huang Mingyang Du Defang Duan Hao Song Tian Cui 《Chinese Physics Letters》 2025年第7期368-387,共20页
Achieving room-temperature superconductivity has been an enduring scientific quest,while hydrogen-rich compounds have emerged as highly promising candidates.Here,we systematically investigated the thermodynamic stabil... Achieving room-temperature superconductivity has been an enduring scientific quest,while hydrogen-rich compounds have emerged as highly promising candidates.Here,we systematically investigated the thermodynamic stability,crystal structure,electronic properties,and superconductivity within the ternary Y-Hf-H system under high pressure.Several distinct hydrides have been revealed,in which the hydrogen atoms are present in various hydrogenic motifs.A15-type hydride P_(m)3-YHfH_(6)with isolated H−is predicted to be dynamically stabilized down to 10GPa.The H atoms form pentagonal graphene-like layered-H10 anions in the Hf plane of P6-YHfH_(19),with aT_(c)of 95K at 100GPa.There are H cages in C_(mmm)-Y_(3)HfH_(24),and attributed to the robust electron–phonon coupling and high electronic density of states of hydrogen at the Fermi level,it demonstrates near-room temperature superconductivity with a T_(c)of 275K at 250GPa.Our work makes contributions to the understanding of the fundamental properties of ternary hydrides under high pressure and provides essential references for further research in this field. 展开更多
关键词 hydrogen rich compounds thermodynamic stability ternary y hf h system hydrogenic motifs crystal structure electronic properties high pressure superconductivity
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Issues towards the maximization of Ni content in resynthesized LiNi_(x)Co_(y)Mn_(z)O_(2)from spent Li-ion batteries
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作者 Gyeongbin Ko Sanghyuk Park +3 位作者 Wooseok Kim Seoa Kim Jihyeon Bae Kyungjung Kwon 《Journal of Energy Chemistry》 2025年第4期723-734,共12页
It is of great importance to explore sustainable and eco-friendly recycling strategies for spent Li-ion batteries(LIBs).As such,the closed-loop resynthesis of LiNi_(x)CoyMn_(z)O_(2)(NCM)becomes recently popular as exe... It is of great importance to explore sustainable and eco-friendly recycling strategies for spent Li-ion batteries(LIBs).As such,the closed-loop resynthesis of LiNi_(x)CoyMn_(z)O_(2)(NCM)becomes recently popular as exemplified by the commercialization of low-and mid-Ni content NCM(33%-60%).However,there has been suspicion as to the successful deployment of Ni-rich NCM resynthesis process.Therefore,we systematically increase the Ni content of NCM from 60%to 90%from the industrial leachate of spent LIBs containing various metallic and nonmetallic impurities.The utilization rate of the leachate decreases from 71.8 mol%for NCM622 to 18.0 mol%for NCM955 as the Ni content in the NCM composition increases with the Co recycling rate being 100%in all resynthesized NCM(RNCM).The physicochemical and electrochemical properties of RNCM are systematically compared with its pristine NCM counterparts.As a result,various physicochemical properties of RNCM including impurity content,crystallographic information,morphology,particle size,porosity,specific surface area,elemental distribution,residual lithium compounds,and thermal stability are correlated with its electrochemical properties.It is found out that Al is the most critical impurity that determines the physicochemical and electrochemical properties of RNCM.It is noteworthy that RNCM955 prepared from spent LIBs without any purification step surpasses NCM955 in terms of rate and cycle performance.Further,this resynthesis approach toward Nirich NCM could meet the forthcoming 2031 EU's legislative target on the mandatory minimum recycling usage of valuable metals from spent LIBs.The anode active material was resynthesized using industrial leachate as the maximum.The amount of leachate used and the amount of impurities were proportional. 展开更多
关键词 Li-ion battery Recycling Resynthesis Cathode material LiNi_(x)Co_(y)Mn_(z)O_(2) Impurity
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Insights into the effect of Y substitution on superlattice structure and electrochemical performance of A_(5)B_(19)-type La-Mg-Ni-based hydrogen storage alloy for nickel metal hydride battery 被引量:1
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作者 Yanan Guo Wenfeng Wang +5 位作者 Huanhuan Su Hang Lu Yuan Li Qiuming Peng Shumin Han Lu Zhang 《Journal of Materials Science & Technology》 2025年第4期60-69,共10页
La-Mg-Ni-based hydrogen storage alloys with superlattice structures are the new generation anode material for nickel metal hydride(Ni-MH)batteries owing to the advantages of high capacity and exceptional activation pr... La-Mg-Ni-based hydrogen storage alloys with superlattice structures are the new generation anode material for nickel metal hydride(Ni-MH)batteries owing to the advantages of high capacity and exceptional activation properties.However,the cycling stability is not currently satisfactory enough which plagues its application.Herein,a strategy of partially substituting La with the Y element is proposed to boost the capacity durability of La-Mg-Ni-based alloys.Furthermore,phase structure regulation is implemented simultaneously to obtain the A5 B19-type alloy with good crystal stability specifically.It is found that Y promotes the phase formation of the Pr5 Co19-type phase after annealing at 985℃.The alloy containing Y contributes to the superior rate capability resulting from the promoted hydrogen diffusion rate.Notably,Y substitution enables strengthening the anti-pulverization ability of the alloy in terms of increasing the volume match between[A_(2)B_(4)]and[AB5]subunits,and effectively enhances the anti-corrosion ability of the alloy due to high electronegativity,realizing improved long-term cycling stability of the alloy from 74.2%to 78.5%after cycling 300 times.The work is expected to shed light on the composition and structure design of the La-Mg-Ni-based hydrogen storage alloy for Ni-MH batteries. 展开更多
关键词 Nickel metal hydride battery y element La-Mg-Ni-based alloy A5 B19-type superlattice structure Electrochemical performance
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Superplasticity of fine-grained Mg−Gd−Y−Zn−Zr alloy prepared via multi-directional forging
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作者 Jing-qi ZHAO Ze-zheng WANG +3 位作者 Chun KE Qiang MENG Chun-xiang ZHANG Jun-ting LUO 《Transactions of Nonferrous Metals Society of China》 2025年第8期2553-2571,共19页
The superplasticity of the Mg−8.59Gd−3.85Y−1.14Zn−0.49Zr alloy was investigated before and after multi-directional forging(MDF)and the mechanisms affecting superplastic deformation were analyzed.The results indicate t... The superplasticity of the Mg−8.59Gd−3.85Y−1.14Zn−0.49Zr alloy was investigated before and after multi-directional forging(MDF)and the mechanisms affecting superplastic deformation were analyzed.The results indicate that after MDF at a temperature of 350℃and strain rates of 0.1 and 0.01 s^(−1)(1-MDFed and 2-MDFed),the superplasticity of the alloy can be significantly improved.The elongations of the MDFed alloys exceed 400%under the strain rate of 6.06×10^(−4)s^(−1)and temperatures of 350,375,and 400℃,and reach the maximum values of 766%(1-MDFed)and 693%(2-MDFed)at 375℃.The grain boundary sliding of the MDFed alloy is sufficient,and the energy barrier of deformation decreases.Theβphase limits the grain growth and promotes dynamic recrystallization,maintaining the stability of the fine-grained structure during superplastic deformation.Several Y-rich phases nucleate in the high-strain region(i.e.,the final fracture region)at high temperatures,accelerating the fracture of the specimen. 展开更多
关键词 Mg−Gd−y−Zn−Zr SUPERPLASTICITy multi-directional forging fracture morphology y-rich phase
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Investigation of mechanical strength and deformation properties of Y25 bogie suspension systems by finite element analysis
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作者 Celalettin Baykara 《Railway Sciences》 2025年第6期685-710,共26页
Purpose–This paper aims to offer a novel viewpoint for improving performance and reliability by developing and optimizing suspension components in a Y25 bogie through material optimization based on wheel–rail intera... Purpose–This paper aims to offer a novel viewpoint for improving performance and reliability by developing and optimizing suspension components in a Y25 bogie through material optimization based on wheel–rail interactions under variable load and track conditions.Design/methodology/approach–The suspension system,a critical component ensuring adaptation to road and load conditions in all vehicle types,is especially vital in heavy freight and passenger trains.In this context,the suspension set of the Y25 bogie–commonly used in T€urkiye and Europe–was modelled using CATIAV5,and stress analyses have been performed by way of ANSYS using the finite element analysis(FEA)method.E300-520-M cast steel was selected for the bogie frame,while two different spring steels,61SiCr7 and 51CrV4,were considered for the suspension springs.The modeled system was subjected to numerical analysis under loading conditions.The resulting stresses and displacements were compared with the mechanical properties of the selected materials to validate the design.Findings–The results demonstrate that the mechanical strength and deformation characteristics of the suspension components vary according to the applied external loads.The stress and displacement responses of the system were found to be within the allowable limits of the selected materials,confirming the structural integrity and reliability of the design.The suspension set is deemed suitable for the prescribed material and environmental conditions,suggesting potential for practical application in real-world rail systems.Originality/value–This research contributes to the design and optimization of bogie suspension systems using advanced CAD/CAE tools.It thinks that the material selection and numerical validation approach presented here can guide future designs in heavy load rail applications and potentially improve both safety and performance. 展开更多
关键词 Finite element analysis y25 railway bogie Suspension system Railway vehicles Wheel-rail interaction
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Study on the influence of the sY1192 gene locus in the AZFb/c region on sperm quality and pregnancy outcome
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作者 Gang-Xin Chen Yan Sun +3 位作者 Rui Yang Zhi-Qing Huang Hai-Yan Li Bei-Hong Zheng 《Asian Journal of Andrology》 2025年第2期231-238,共8页
Y chromosome microdeletions are an important cause of male infertility.At present,research on the Y chromosome is mainly focused on analyzing the loss of large segments of the azoospermia factor a/b/c(AZFa/b/c)gene,an... Y chromosome microdeletions are an important cause of male infertility.At present,research on the Y chromosome is mainly focused on analyzing the loss of large segments of the azoospermia factor a/b/c(AZFa/b/c)gene,and few studies have reported the impact of unit point deletion in the AZF band on fertility.This study analyzed the effect of sperm quality after sY1192 loss in 116 patients.The sY1192-independent deletion accounted for 41.4%(48/116).Eight patterns were found in the deletions associated with sY1192.The rate of sperm detection was similar in the semen of patients with the independent sY1192 deletion and the combined sY1192 deletions(52.1%vs 50.0%).The patients with only sY1192 gene loss had a higher probability of sperm detection than the patients whose sY1192 gene locus existed,but other gene loci were lost(52.1%vs 32.0%).The hormone levels were similar in patients with sY1192 deletion alone and in those with sY1192 deletion and other types of microdeletions in the presence of the sY1192 locus.After multiple intracytoplasmic sperm injection(ICSI)attempts,the pregnancy rate of spouses of men with sY1192-independent deletions was similar to that of other types of microdeletions,but the fertilization and cleavage rates were higher.We observed that eight deletion patterns were observed for sY1192 microdeletions of AZFb/c,dominated by the independent deletion of sY1192.After ICSI,the fertilization rate and cleavage rate of the sY1192-independent microdeletion were higher than those of other Y chromosome microdeletion types,but there was no significant difference in pregnancy outcomes. 展开更多
关键词 assisted reproductive technology AZFb/c pregnancy outcome sy1192 y chromosome microdeletion
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Aligned nanofiber scaffolds combined with cyclic stretch facilitate mesenchymal stem cell differentiation for ligament engineering
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作者 Cheng-Wei Yang Ya-Qiang Zhang +3 位作者 Hong Chang Rui Gao Dan Chen Hao Yao 《World Journal of Stem Cells》 2025年第8期150-162,共13页
BACKGROUND Tendon tissue engineering requires biomimetic scaffolds and mechanical cues to direct mesenchymal stem cell differentiation toward tenogenic lineages.Bone marrow-derived mesenchymal stem cells(BMSCs),aligne... BACKGROUND Tendon tissue engineering requires biomimetic scaffolds and mechanical cues to direct mesenchymal stem cell differentiation toward tenogenic lineages.Bone marrow-derived mesenchymal stem cells(BMSCs),aligned nanofiber scaffolds,and cyclic uniaxial stretching can be used to create a functional engineered ligament tissue.AIM To investigate the effects of aligned nanofiber scaffolds and cyclic stretch on BMSC tenogenesis for ligament engineering.METHODS BMSCs were cultured on aligned and random poly-lactic acid nanofiber scaffolds under static and cyclic tensile conditions(0.5 Hz,2%strain,2 hours/day)for 7 days using a mechanical loading system(CFILLOAD-300).The Ras homolog gene family(Rho)-associated coiled coil-containing kinase(ROCK)inhibitor Y27632 was applied to explore its role in tenogenic differentiation.Scaffold morphology was assessed by scanning electron microscopy,while cell morphology,viability,and alignment were evaluated via confocal microscopy with F-actin and 4’,6-diamidino-2-phenylindole staining.Tenogenic gene expression(collagen type I alpha 2,collagen type III alpha 1,tenascin C,and tenomodulin)was quantified by quantitative polymerase chain reaction,and ligament-related protein levels(collagen I,collagen III,tenascin C,and tenomodulin)were analyzed by western blot.RESULTS Scanning electron microscopy revealed that aligned scaffolds provided consistent directional structure,whereas random scaffolds displayed a disordered fiber arrangement.Confocal microscopy showed that under static conditions,BMSCs on aligned scaffolds grew parallel to fiber alignment,while those on random scaffolds grew randomly.Under cyclic tensile strain,BMSCs on both scaffold types exhibited elongation along the direction of strain,adopting a spindle-shaped morphology.Cyclic uniaxial strain enhanced cell viability and metabolic activity based on CCK-8 assay results and upregulated ligament-specific gene and protein expression on aligned scaffolds compared to static conditions.BMSCs on aligned scaffolds under tensile strain showed the highest expression of tenogenic markers,suggesting a synergistic effect of scaffold alignment and mechanical loading.ROCK inhibition with Y27632 upregulated alternative signaling pathways(focal adhesion kinase and runt-related transcription factor 2),further promoting tenogenic differentiation.CONCLUSION Aligned nanofiber scaffolds combined with cyclic tensile strain provide an optimal environment for guiding BMSC differentiation toward ligamentous lineages,as assessed by increased expression of ligament-specific markers.Mechanical stimulation(uniaxial stretching)significantly influences BMSC tenogenic differentiation,and the combined use of aligned nanofibers and tensile strain further enhances this effect.The ROCK pathway plays a regulatory role in this process,though its precise mechanisms require further investigation. 展开更多
关键词 Tendon tissue engineering Bone marrow-derived mesenchymal stem cells Nanofiber scaffold Cyclic tensile strain Tenogenic differentiation Ras homolog gene family(Rho)-associated coiled coil-containing kinase inhibition y27632
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异源过表达大豆GmNF-YB24提高转基因烟草抗旱性
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作者 翟莹 计俊杰 +4 位作者 陈炯辛 于海伟 李珊珊 赵艳 马天意 《生物技术通报》 北大核心 2025年第8期137-145,共9页
【目的】核因子(NF-Y)基因参与植物抗旱性的调控。对大豆GmNF-YB24的抗旱功能及抗旱机制进行解析,为后续NF-YB基因在高抗大豆遗传育种中的应用提供理论依据。【方法】利用RT-qPCR检测GmNF-YB24在盐、干旱和低温胁迫下的表达。克隆Gm NF-... 【目的】核因子(NF-Y)基因参与植物抗旱性的调控。对大豆GmNF-YB24的抗旱功能及抗旱机制进行解析,为后续NF-YB基因在高抗大豆遗传育种中的应用提供理论依据。【方法】利用RT-qPCR检测GmNF-YB24在盐、干旱和低温胁迫下的表达。克隆Gm NF-YB24,构建植物表达载体并转化烟草。对GmNF-YB24转基因烟草的抗旱性进行鉴定。【结果】盐、干旱和低温胁迫均能诱导GmNF-YB24的表达,且GmNF-YB24的表达对干旱胁迫的响应最明显。GmNF-YB24开放阅读框全长516 bp,编码的蛋白含有171个氨基酸残基。GmNF-YB24蛋白序列中含有1个组蛋白折叠基序(HFM)。构建pRI101-GmNF-YB24植物表达载体并转化烟草。共获得5株GmNF-YB24转基因烟草植株(OE1-OE5)。干旱及复水处理后,GmNF-YB24转基因烟草的表现优于野生型烟草。干旱胁迫下,与野生型烟草相比,GmNF-YB24转基因烟草的脯氨酸和可溶性糖含量增加,相对电解质渗透率和丙二醛含量降低,抗氧化酶活性提高,减少了过氧化物的积累。GmNF-YB24转基因烟草中胁迫相关基因NtOsmotin和NtERD10B的表达量高于野生型烟草。【结论】GmNF-YB24在烟草中的异源过表达提高了转基因烟草的抗旱性。 展开更多
关键词 大豆 核因子y NF-yB 转基因烟草 抗旱性
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Quantitative Strengthening Evaluation of Mg-Zn-Y Alloys Containing Icosahedral Quasi-Crystalline Phase
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作者 Wang Yingnan Meng Xiaokai Guo Junhong 《稀有金属材料与工程》 北大核心 2025年第3期612-617,共6页
Mg-4.8Zn-0.8Y,Mg-18Zn-3Y,Mg-15Zn-5Y,Mg-30Zn-5Y and Mg-42Zn-7Y(wt%)alloys containing icosahedral quasicrystalline phases were prepared using the ordinary solidification method.The impact of Mg matrix porosity on the te... Mg-4.8Zn-0.8Y,Mg-18Zn-3Y,Mg-15Zn-5Y,Mg-30Zn-5Y and Mg-42Zn-7Y(wt%)alloys containing icosahedral quasicrystalline phases were prepared using the ordinary solidification method.The impact of Mg matrix porosity on the tensile strength and hardness of the alloys was studied.The porosity of the Mg matrix was quantitatively assessed using scanning electron microscope and Image-Pro Plus 6.0 software.Tensile tests were conducted at room temperature.Results show that the maximum tensile strength of the alloy is 175.56 MPa,with a corresponding Mg matrix porosity of 76.74%.Through fitting analysis,it is determined that the maximum tensile strength is achieved when the porosity of the Mg matrix is 64.87%.The microhardness test results indicate a gradual decrease in alloy hardness with increasing the porosity of Mg matrix.This study provides an effective quantitative analysis method for enhancing the mechanical properties of magnesium alloys. 展开更多
关键词 Mg-Zn-y alloy Mg matrix porosity mechanical properties quantitative analysis
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Assessing microcatheter-assisted 360-degree trabeculotomy combined with trabeculectomy for refractory glaucoma:1-year results
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作者 Jia-Yin Qin Yan Liu Tao Wang 《International Journal of Ophthalmology(English edition)》 2025年第1期94-102,共9页
AIM:To evaluate the efficacy and safety of microcatheterassisted 360-degree trabeculotomy combined with trabeculectomy(MATT-Trab)for treating refractory glaucoma.METHODS:Patients with refractory glaucoma who underwent... AIM:To evaluate the efficacy and safety of microcatheterassisted 360-degree trabeculotomy combined with trabeculectomy(MATT-Trab)for treating refractory glaucoma.METHODS:Patients with refractory glaucoma who underwent MATT-Trab were retrospectively examined.Efficacy indicators for research statistics included the intraocular pressure(IOP)level,degree of decrease,changes in medication dosage,and success rate.Safety indicators included the best-corrected visual acuity and incidence of complications.RESULTS:This study comprised 31 patients,including 11 males and 20 females,with ages ranging from 8mo to 67y(mean age:29.40±22.10y).The average postoperative IOP at 1d,1wk,1mo,3mo,6mo,1y,and the last followup was significantly lower than the average preoperative IOP(31.33±9.24 mm Hg,P<0.05).The average number of postoperative medications at 1y was 0.48±1.51,which was significantly reduced compared to that used preoperatively(3.77±0.99,P=0.00).The absolute and qualified success rates were 45.16% and 83.87%,respectively.Visual acuity exhibited no statistically significant difference between the postoperative and preoperative follow-up time points,except for the first day after surgery.The most common postoperative complications were anterior chamber hemorrhage(25 cases,86.21%)and high IOP(10 cases,34.48%).CONCLUSION:Our results indicate that MATT-Trab is effective and safe for treating refractory glaucoma. 展开更多
关键词 GLAUCOMA refractor y glaucoma TRABECULOTOMy TRABECULECTOMy MICROCATHETER
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补骨脂酚抑制PI3K/Akt/Nrf2/HO-1对氧糖剥夺所致SH-SY5Y细胞损伤的作用及机制 被引量:2
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作者 徐玥玮 张珅 +6 位作者 高晓明 王丽 杨满琴 张梦翔 杨晓丹 戴文玲 蔡明 《药物评价研究》 北大核心 2025年第2期448-454,共7页
目的研究补骨脂酚对氧糖剥夺/复糖复氧(OGD/R)诱导人源性神经母细胞瘤细胞(SH-SY5Y)损伤的影响。方法MTT法检测补骨脂酚(5、10、20、40、80μmol·L^(-1))对SH-SY5Y细胞活性的影响。将SH-SY5Y细胞分为对照组、模型组、补骨脂酚(5、1... 目的研究补骨脂酚对氧糖剥夺/复糖复氧(OGD/R)诱导人源性神经母细胞瘤细胞(SH-SY5Y)损伤的影响。方法MTT法检测补骨脂酚(5、10、20、40、80μmol·L^(-1))对SH-SY5Y细胞活性的影响。将SH-SY5Y细胞分为对照组、模型组、补骨脂酚(5、10、20μmol·L^(-1))组、补骨脂酚(20μmol·L^(-1))+ML385(2μmol·L^(-1),Nrf2抑制剂)组、补骨脂酚(20μmol·L^(-1))+LY294002[5μmol·L^(-1),磷脂酰肌醇3-激酶(PI3K)抑制剂]组。MTT法检测SH-SY5Y细胞活力,倒置显微镜观察各组SH-SY5Y细胞形态,试剂盒法检测细胞上清超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性,实时荧光定量PCR(q RT-PCR)法和Western blotting法测定磷脂酰肌醇3-激酶(PI3K)、丝氨酸/苏氨酸激酶B(Akt)、核因子E2相关因子2(Nrf2)、血红素加氧酶1(HO-1)mRNA和蛋白水平。结果补骨脂酚对正常SH-SY5Y细胞存活率无影响。与对照组比较,模型组细胞存活率显著下降(P<0.01),细胞个数明显减少,部分细胞裂解成碎片,部分细胞死亡;SOD、CAT活性显著降低(P<0.01),PI3K/Akt/Nrf2/HO-1 mRNA及蛋白水平显著下调(P<0.05、0.01、0.001)。与模型组比较,补骨脂酚显著增加细胞存活率(P<0.01),明显增加细胞个数,显著上调SOD、CAT活性(P<0.05、0.01),显著上调PI3K/Akt/Nrf2/HO-1 mRNA及蛋白水平(P<0.05、0.01、0.001)。与补骨脂酚(20μmol·L^(-1))组比较,补骨脂酚+ML385可逆转补骨脂酚对HO-1 mRNA及蛋白的上调作用(P<0.05、0.01),补骨脂酚+LY294002可逆转补骨脂酚对Nrf2、HO-1 mRNA及蛋白水平的上调作用(P<0.05、0.01)。结论补骨脂酚可显著改善OGD/R诱导的SH-SY5Y细胞损伤,且机制可能是通过激活PI3K/Akt进而上调Nrf2/HO-1抑制氧化应激改善神经损伤。 展开更多
关键词 补骨脂酚 SH-Sy5y细胞 脑缺血再灌注 氧糖剥夺/复糖复氧 Nrf2/HO-1 PI3K/AKT
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A cross-sectional study of the association between dietary inflammatory index and glaucoma prevalence in a US population
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作者 Wen-Li Chen Li-Xia Zhang 《International Journal of Ophthalmology(English edition)》 2025年第1期139-145,共7页
AIM:To assess the relationship between dietary inflammatory index(DII)and prevalence of glaucoma among individuals aged 40y and above in the United States.METHODS:Participants were drawn from 2 cycles of the National ... AIM:To assess the relationship between dietary inflammatory index(DII)and prevalence of glaucoma among individuals aged 40y and above in the United States.METHODS:Participants were drawn from 2 cycles of the National Health and Nutrition Examination Survey(NHANES,2005-2008)for a cross-sectional study.DII was calculated from 24-hour dietary recall questionnaire conducted by experienced researchers and data analyzed in R according to the NHANES user guide,“Stratified Multi-stage Probability Sampling”.The relationship between DII and glaucoma was evaluated by multi-factor logistic regression analysis and the existence of a non-linear association examined by restricted cubic spline(RCS)analysis.RESULTS:A total of 5359 subjects were included and the cross-sectional analysis weighted to represent the US population of 109 million.DII was elevated in glaucoma patients(P<0.001)and smoking and alcohol use contributed to significant differences(P<0.001).DII correlated negatively with Healthy Eating Index(HEI)-2015(Spearman rank correlation coefficient,r=-0.49).RCS analysis showed a linear relationship between DII and glaucoma risk(P of non-linear relationship=0.575).CONCLUSION:An increased DII is strongly associated with high risk of glaucoma and diet-induced inflammation should be controlled to delay glaucoma progression. 展开更多
关键词 glaucoma risk factors dietar y inflammatory index National Health and Nutrition Examination Survey restricted cubic spline regression cross-sectional study
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CO_(2)-promoted ethylbenzene dehydrogenation catalyzed by zeolite-encaged single chromium sites
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作者 Jian Dang Xin Deng +3 位作者 Weijie Li Di Yang Guangjun Wu Landong Li 《Chinese Journal of Catalysis》 2025年第4期158-168,共11页
The selective activation of C-H bonds is pivotal in catalysis for converting hydrocarbons into value-added chemicals.Ethylbenzene dehydrogenation to styrene is crucial process to produce polystyrene and its derivative... The selective activation of C-H bonds is pivotal in catalysis for converting hydrocarbons into value-added chemicals.Ethylbenzene dehydrogenation to styrene is crucial process to produce polystyrene and its derivatives used in synthetic materials.Herein,K-Cr@Y with zeolite-encaged isolated O=Cr(VI)=O species modified by extraframework potassium ions is constructed,showing remarkable performance in CO_(2)-promoted ethylbenzene dehydrogenation with initial ethylbenzene conversion of 66%and styrene selectivity of 96%,outperforming other M-Cr@Y catalysts(M=Li,Na,Rb,Cs).Extraframework potassium ions can modulate the electron density of zeolite-encaged Cr(VI)species and therefore facilitate C–H bond activation in ethylbenzene molecules.The gradual reduction of zeolite-encaged O=Cr(VI)=O to less active Cr(IV)=O species by dihydrogen during ethylbenzene dehydrogenation is evidenced by comprehensive characterization results,and Cr(IV)=O can be re-oxidized to O=Cr(VI)=O species upon simple calcination regeneration.The results from in situ DRIFT spectroscopy elucidate the critical promotion role of CO_(2)in ethylbenzene dehydrogenation over K-Cr@Y by retarding the over-reduction of zeolite-encaged Cr species to inactive Cr(III)species and suppressing coke deposition.This study advances the rational design of non-noble metal catalysts for CO_(2)-promoted ethylbenzene dehydrogenation with zeolite-encaged high valence transition metal ions modulated by extraframework cations. 展开更多
关键词 C-H bond activation CO_(2)-promoted ethylbenzene DEHyDROGENATION K-Cr@y O=Cr(VI)=O Cr(IV)=O
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一种针对^(90)Y的淬灭指数及其在^(90)Sr分析中的新应用
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作者 冯孝贵 袁建华 +4 位作者 何千舸 靳小军 孔雪艳 王建晨 陈靖 《核化学与放射化学》 北大核心 2025年第3期259-266,共8页
采用自定义的、针对^(90)Y的淬灭指数qx,结合改进双窗法,建立了一种用液闪仪(有时需要辅以γ谱仪)分析^(90)Sr的方法。使用该方法的前提有两点:(1)样品的淬灭水平较低,^(90)Sr或^(90)Y在全谱范围内的计数效率可以近似为100%;(2)^(90)Y... 采用自定义的、针对^(90)Y的淬灭指数qx,结合改进双窗法,建立了一种用液闪仪(有时需要辅以γ谱仪)分析^(90)Sr的方法。使用该方法的前提有两点:(1)样品的淬灭水平较低,^(90)Sr或^(90)Y在全谱范围内的计数效率可以近似为100%;(2)^(90)Y液闪谱图高能部分没有其它β核素的干扰。以高放废液分离热实验的三类真实样品为例,说明了该方法的具体使用步骤。实验采用的样品已达到^(90)Sr/^(90)Y放射性衰变平衡,因此可以用三种思路计算^(90)Sr含量,彼此相互验证。结果表明,用本方法得到的^(90)Sr含量是准确可靠的。本方法只需要对液闪谱图高能部分进行线性拟合,简单、易于操作,使用者可以根据待测样品的特点及分析要求,按应用建议选择合适的分析策略。对于^(90)Sr/^(90)Y样品(可含^(137)Cs),如果^(90)Sr的计数率占比不是太低,用本方法对^(90)Sr含量进行测定时,既不需要进行化学分离,也不需要等待^(90)Sr/^(90)Y放射性衰变平衡。 展开更多
关键词 液闪 淬灭指数 改进双窗法 线性拟合 ^(90)Sr ^(90)y
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基于Y型驱避测定尺的红火蚁驱避剂筛选新方法
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作者 石庆型 孙文锋 +4 位作者 陈婷 陈洁 关子盈 陆嘉进 齐国君 《环境昆虫学报》 北大核心 2025年第2期411-419,共9页
筛选测定方法是开发红火蚁Solenopsis invicta Buren驱避剂的重要环节,目前尚缺乏针对攻击水平较高的红火蚁驱避活性的测定方法。本研究利用自主研发的一种Y型驱避测定尺监测了红火蚁工蚁的活动规律,对比了裸型和绷带型Y型驱避测定尺对... 筛选测定方法是开发红火蚁Solenopsis invicta Buren驱避剂的重要环节,目前尚缺乏针对攻击水平较高的红火蚁驱避活性的测定方法。本研究利用自主研发的一种Y型驱避测定尺监测了红火蚁工蚁的活动规律,对比了裸型和绷带型Y型驱避测定尺对攀爬红火蚁工蚁数量的影响,并测定了避蚊胺对红火蚁工蚁的驱避活性。结果表明:Y型驱避测定尺的侧臂长度与红火蚁工蚁的密度呈负相关,选择侧臂长度11 cm的Y型驱避测定尺用于驱避活性测定。室内红火蚁工蚁受惊扰后75 s内数量涨幅较大,而田间红火蚁工蚁受扰动后30 s时数量可达到峰值,裸型和绷带型Y型驱避测定尺的工蚁数量在不同时间点上均无显著性差异(P>0.05)。避蚊胺对红火蚁的驱避效果显著,随着处理浓度上升,驱避率和有效驱避时间也随之提高,裸型和绷带型Y型驱避测定尺分别在5.0%和10.0%浓度时的驱避率达到100%,当避蚊胺浓度为5.0%时,裸型尺和绷带型尺的有效驱避时间分别可达198.16 min、228.14 min。本研究设计并优化的Y型驱避测定尺可直接测定化合物对惊扰状态下红火蚁的驱避活性,为红火蚁驱避剂的筛选与评价提供了一种新方法,同时也为红火蚁个体防护剂的研发提供了技术支撑。 展开更多
关键词 红火蚁 y型驱避测量尺 避蚊胺 驱避效果
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呈现特纳综合征表型的45,X/46,XY性发育异常患儿15例临床分析
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作者 刘晓景 刘素华 +3 位作者 高静 郝会民 卫海燕 刘敏 《临床儿科杂志》 北大核心 2025年第5期345-349,共5页
目的总结呈现特纳综合征表型的45,X/46,XY性发育异常患儿的临床特点、青春期发育状况、性腺肿瘤发生情况及转归。方法回顾性分析2012年1月至2023年1月于河南省儿童医院就诊的呈现特纳综合征表型的45,X/46,XY性发育异常患儿的临床资料。... 目的总结呈现特纳综合征表型的45,X/46,XY性发育异常患儿的临床特点、青春期发育状况、性腺肿瘤发生情况及转归。方法回顾性分析2012年1月至2023年1月于河南省儿童医院就诊的呈现特纳综合征表型的45,X/46,XY性发育异常患儿的临床资料。结果15例患儿均为女性表型,伴生长发育迟缓,有颈蹼、肘外翻等典型特纳综合征临床特征;3例呈现自发性乳房发育,1例自发性月经初潮,最终均出现性腺发育不良。染色体中Y染色体嵌合比率为5%~85%。10例进行SRY基因检测,均为阳性。7例性腺切除后进行病理检查,发现3例性腺肿瘤(1例单侧性腺母细胞瘤、1例无性细胞瘤和1例原位生殖细胞瘤),其中1例原位生殖细胞瘤在诊断时已恶变,诊断年龄为4.3岁。结论45,X/46,XY性发育异常部分患儿可呈现类似特纳综合征的临床特征,性腺肿瘤发生率和恶变率高,恶变年龄小,临床上对此应予以充分的重视,及时评估手术介入的必要性。 展开更多
关键词 性发育异常 y染色体嵌合 SRy基因 性腺母细胞瘤 生殖细胞瘤
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外踝前静脉网多段倒“Y”型静脉移植修复掌浅弓以远断掌损伤
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作者 张钊 王燕燕 +6 位作者 高飞 潘月海 黄恒 路超 王国忠 屈志刚 毕本军 《中国修复重建外科杂志》 北大核心 2025年第5期628-632,共5页
目的探讨外踝前静脉网多段倒“Y”型静脉移植修复掌浅弓以远损伤治疗复杂断掌的临床效果。方法2018年9月—2023年7月,收治5例机器损伤导致的伴掌浅弓以远损伤断掌患者。男3例,女2例;年龄29~52岁,平均35.4岁。受伤至入院时间1~6 h,平均3.... 目的探讨外踝前静脉网多段倒“Y”型静脉移植修复掌浅弓以远损伤治疗复杂断掌的临床效果。方法2018年9月—2023年7月,收治5例机器损伤导致的伴掌浅弓以远损伤断掌患者。男3例,女2例;年龄29~52岁,平均35.4岁。受伤至入院时间1~6 h,平均3.2 h。术中切取患侧外踝前静脉网多段倒“Y”型静脉,移植于掌浅弓以远指掌侧总动脉与指固有动脉缺损处;以对侧外踝前静脉网移植重建手背静脉。1例伴手背软组织缺损,采用髂腹股沟带蒂皮瓣修复;供区直接拉拢缝合。术后给予抗感染、抗痉挛、预防血栓形成等处理。结果术后1例发生拇指指尖部分坏死,1例髂腹股沟皮瓣边缘坏死;其余手指血运良好,张力正常。腹部皮瓣供区切口Ⅰ期愈合。5例患者均获随访,随访时间8~41个月,中位时间19个月。末次随访时,患者手部外形满意;手指抓握及对掌功能恢复;本体感觉恢复,两点辨别觉5~7 mm,平均6 mm;根据中华医学会上肢部分功能评定试用标准,患肢功能获优3例、良1例、差1例。结论外踝前静脉网多段倒“Y”型静脉移植修复掌浅弓以远指掌侧总动脉及指固有动脉缺损,具有位置表浅、取材灵活、匹配度高等优势,用于复杂断掌修复重建可获得较好疗效。 展开更多
关键词 外踝前静脉网 掌浅弓 血管移植 断掌 y型静脉
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Y添加和热处理对Al-Mg-Si-Y合金组织与性能的影响
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作者 毕晓勤 张森 +3 位作者 郑泽远 齐玉蕾 付莹 徐琴 《金属热处理》 北大核心 2025年第2期148-154,共7页
制备了Al-0.6Mg-0.5Si-xY(x=0,0.1,0.2,0.3,0.4)合金,并进行T6热处理,研究了热处理后合金的组织演变、导电性和力学性能。结果表明,热处理后添加Y的合金晶界处形成了AlSiY相,晶内析出颗粒状和棒状的AlSiY相,基体弥散分布着白色颗粒状的M... 制备了Al-0.6Mg-0.5Si-xY(x=0,0.1,0.2,0.3,0.4)合金,并进行T6热处理,研究了热处理后合金的组织演变、导电性和力学性能。结果表明,热处理后添加Y的合金晶界处形成了AlSiY相,晶内析出颗粒状和棒状的AlSiY相,基体弥散分布着白色颗粒状的Mg2Si相。热处理后合金平均晶粒尺寸较铸态增大,且Y添加量越多,合金平均晶粒尺寸越小。热处理后合金导电率随Y添加量的增加先升高后降低,添加0.3%Y时,导电率最高为55.2%IACS,较铸态提高1.7%。热处理后合金晶粒增大使晶界减少,且固溶Si原子的析出降低固溶畸变,从而提高合金导电率。热处理态合金抗拉强度和硬度较铸态提高,且随Y添加量的增加先增加后降低,添加0.3%Y时,分别达最高值206.2 MPa和91.3 HV0.1,较铸态提高36.6%和40.5%。热处理态合金的伸长率较铸态有明显下降。热处理后,合金中大量的析出相提高了合金的强度和硬度,而晶界减少、析出相增多使热处理态合金伸长率较铸态降低。 展开更多
关键词 AL-MG-SI合金 y添加 热处理 微观组织 导电性能 力学性能
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三进一回Y型通风下瓦斯动态演化规律及风量二次规划研究
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作者 梁运培 郭亚博 +4 位作者 李全贵 孙万杰 李赏 郑梦浩 王程成 《矿业安全与环保》 北大核心 2025年第3期56-64,共9页
为了研究三进一回Y型通风工作面及采空区瓦斯的动态演化规律,探索进风巷风量最优配比,以山西某矿31002工作面为研究对象建立多孔介质模型,基于Fluent实现工作面及采空区的瓦斯流场数值模拟。分析了三进一回Y型通风瓦斯流场中瓦斯浓度、... 为了研究三进一回Y型通风工作面及采空区瓦斯的动态演化规律,探索进风巷风量最优配比,以山西某矿31002工作面为研究对象建立多孔介质模型,基于Fluent实现工作面及采空区的瓦斯流场数值模拟。分析了三进一回Y型通风瓦斯流场中瓦斯浓度、气体压力、风流的基本分布规律,以及3条进风巷不同风量配比下瓦斯浓度的演化规律。通过模拟生成30组样本数据,拟合后生成风量与上隅角瓦斯浓度之间的多元非线性回归函数关系式,根据数值模拟的先验规律对目标函数进行二次规划求解,最终得到最优的风量配比。研究表明:进风巷2、3位置接近,靠近工作面区域会出现涡流,在一定程度上会导致瓦斯富集;当进风巷1的风量大于其余2条进风巷风量之和时,瓦斯富集区域主要集中于沿工作面长度约90 m处至上隅角区域,采空区靠近工作面处瓦斯浓度富集区域为90~220 m,改变进风巷2、3之间的风量配比后瓦斯浓度平均下降约0.19%;目标函数在先验规律约束下,得出3条进风巷最优风量配比为1.08∶1.23∶1.23。研究结果为工作面瓦斯超限治理、矿井瓦斯灾害防治提供了理论支撑。 展开更多
关键词 y型通风 最优风量配比 上隅角 瓦斯流场 瓦斯超限
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老年脑卒中患者血清神经元特异性烯醇化酶和神经肽Y水平与睡眠障碍的关系
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作者 吴芳 刘崇 李菓 《中华老年心脑血管病杂志》 北大核心 2025年第10期1372-1375,共4页
目的探讨老年脑卒中患者血清神经元特异性烯醇化酶(neuron-specific enolase,NSE)、神经肽Y(neuropeptide Y,NPY)、下丘脑外侧区分泌素(hypocretin,Hcrt)水平变化与睡眠障碍的关系。方法回顾性选取2021年2月至2024年2月南阳市第一人民... 目的探讨老年脑卒中患者血清神经元特异性烯醇化酶(neuron-specific enolase,NSE)、神经肽Y(neuropeptide Y,NPY)、下丘脑外侧区分泌素(hypocretin,Hcrt)水平变化与睡眠障碍的关系。方法回顾性选取2021年2月至2024年2月南阳市第一人民医院神经内二科接诊的老年脑卒中患者105例,根据匹兹堡睡眠质量指数量表(Pittsburgh sleepquality index,PSQI)评估结果分为睡眠障碍组64例,非睡眠障碍组41例。入院时检测血清NSE、NPY、Hcrt水平,采用PSQI进行睡眠状态评估,比较两组NSE、NPY、Hcrt水平,多因素logistic回归分析老年脑卒中患者发生睡眠障碍的影响因素,并进行ROC曲线分析。结果睡眠障碍组NSE水平显著高于非睡眠障碍组,NPY、Hcrt水平显著低于非睡眠障碍组(P<0.01)。多因素logistic回归分析显示,NSE、NPY、Hcrt、年龄、美国国立卫生研究院卒中量表评分、脑卒中史是老年脑卒中患者发生睡眠障碍的影响因素(P<0.05,P<0.01)。ROC曲线分析显示,NSE、NPY、Hcrt预测老年脑卒中患者发生睡眠障碍的曲线下面积分别为0.797、0.754、0.915。结论血清NSE、NPY、Hcrt与老年脑卒中患者睡眠障碍紧密关联,且对预测睡眠障碍发生有重要价值。 展开更多
关键词 卒中 睡眠障碍 神经肽y 神经元特异性烯醇化酶
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