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Magnesium isoglycyrrhizinate ameliorates isoproterenol-induced myocardial remodeling in mice by regulating oxidative stress and apoptosis via the PI3K/AKT1 signaling pathway 被引量:2
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作者 Xingyu Zhou Dan Fu +8 位作者 Saige Sun Qiuyan Liu Longxing Liu Jia Shi Zijie Ge yu ma Yilin He Li Xu Kai Qian 《Journal of Chinese Pharmaceutical Sciences》 2025年第4期321-333,共13页
The aim of this study is to investigate the mechanism of magnesium isoglycyrrhizinate(MgIG)in the treatment of myocardial remodeling induced by isoproterenol(ISO)in mice.We assessed the impact of MgIG on ISO-induced m... The aim of this study is to investigate the mechanism of magnesium isoglycyrrhizinate(MgIG)in the treatment of myocardial remodeling induced by isoproterenol(ISO)in mice.We assessed the impact of MgIG on ISO-induced myocardial remodeling by activating the PI3K/AKT1 pathway.The cardiac function of mice was evaluated by echocardiography,revealing that MgIG could improve left ventricular function.Pathological staining analysis showed that MgIG could reduce the degree of myocardial injury caused by ISO.Serum data detected by ELISA demonstrated that MgIG could decrease the levels of CK-MB,MDA,and LDH while increasing the activity of GSH-Px.Western blotting analysis revealed that protein expression levels of Collagen I,BNP,Bax,cleaved caspase-3,p-PI3K,and p-AKT1 were decreased,whereas the protein expressions of Bcl-2,COX2,and SOD1 were increased upon MgIG treatment.However,the activation of the PI3K pathway reversed the cardioprotective effects of MgIG,as evidenced by the addition of PI3K activators.Taken together,our comprehensive results suggested that MgIG could improve ISO-induced myocardial remodeling,potentially through its mechanism of inhibiting the PI3K/AKT1 pathway to regulate apoptosis and oxidative stress. 展开更多
关键词 Magnesium isoglycyrrhizinate ISOPROTERENOL Myocardial remodeling PI3K/AKT1 APOPTOSIS Oxidative stress
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Application of aromatherapy in patients with cognitive impairment:An integrative review
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作者 Die XING Xin CHEN +5 位作者 yu ma Mengmeng CHEN Mei Fung HO Kylie Ka Yee LAM Ying ZHOU Thomas Kwok Shing WONG 《Journal of Integrative Nursing》 2025年第2期95-111,共17页
This integrative review examines the therapeutic applications of aromatherapy in cognitive impairment spectrum disorders,spanning from subjective cognitive decline to dementia.A comprehensive search across twelve data... This integrative review examines the therapeutic applications of aromatherapy in cognitive impairment spectrum disorders,spanning from subjective cognitive decline to dementia.A comprehensive search across twelve databases(PubMed,Web of Science,Embase,Cochrane Library,Scopus,OVID,EBSCOhost,ProQuest,CNKI,WF,VIP,and CBM)identified 28 studies up to March 2024,analyzed through Whittemore and Knafl’s five-stage framework with mixed methods appraisal tool(MMAT)quality appraisal and Template for Intervention Description and Replication-guided data extraction.Three primary intervention modalities emerged:inhalation(most prevalent),massage,and combined approaches,employing diverse essential oils with variations in dosage,administration timing,and environmental contexts.Outcome assessments covered cognitive performance,neuropsychiatric symptoms,functional abilities,quality of life metrics,caregiver impacts,and safety profiles.When demonstrating therapeutic potential,significant heterogeneity in essential oil selection(types and concentrations)and intervention protocols hindered comparative analysis.Future research should focus on understanding the compositions of essential oils to establish appropriate applications and dosage guidelines.In addition,more reliable information on safe inhalation methods is necessary,alongside the exploration of traditional Chinese medicine essential oils to enhance aromatherapy practices.High-quality randomized controlled trials are essential to assess the effectiveness and safety of aromatherapy in this context. 展开更多
关键词 AROMATHERAPY cognitive impairment essential oils integrative review
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A Rb-Cs dual-species magneto-optical trap
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作者 Shiyao Shao Qing Li +13 位作者 Lihua Zhang Bang Liu Zhengyuan Zhang Qifeng Wang Jun Zhang yu ma Tianyu Han Hanchao Chen Jiadou Nan Yiming Yin Dongyang Zhu Yajun Wang Dongsheng Ding Baosen Shi 《Chinese Physics B》 2025年第6期147-152,共6页
We describe a three-dimensional(3D) magneto-optical trap(MOT) capable of simultaneously capturing ^(85)Rb and ^(133)Cs atoms. Unlike conventional setups, our system utilizes two separate laser systems that are combine... We describe a three-dimensional(3D) magneto-optical trap(MOT) capable of simultaneously capturing ^(85)Rb and ^(133)Cs atoms. Unlike conventional setups, our system utilizes two separate laser systems that are combined before entering the vacuum chamber, enabling the simultaneous trapping of two different atomic species. We trapped ^(85)Rb and ^(133)Cs atoms using relatively low total power: 8 mW cooling and 4 mW repump for ^(85)Rb, and 7.5 mW cooling and 1.5 mW repump for ^(133)Cs. The number of trapped atoms was 1.6 × 10^(8) for ^(85)Rb and 1.4 × 10^(8) for ^(133)Cs. The optical depths were 3.71 for ^(85)Rb and 3.45 for ^(133)Cs. The temperature of trapped atoms was ~200 μK for ^(85)Rb and ~200 μK for ^(133)Cs. Our 3D MOT setup allows full horizontal optical access to the trapped atomic ensembles without spatial interference from the trapping or repump laser beams. Our vacuum system is also quite simple, avoiding much of the complexity typically encountered in similar dual-species systems. However, the red detuning of the cooling laser used for atomic trapping in our system is relatively small, leaving room for further optimization. This system offers a versatile platform for exploring complex phenomena in ultracold atom physics, such as Rydberg molecule formation and interspecies interactions. 展开更多
关键词 dual-species systems magneto-optical trap ultracold atom
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Reduced-order method for nuclear reactor primary circuit calculation
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作者 Ze-Long Zhao Ya-Hui Wang +2 位作者 Zhe-Xian Liu Hong-Hang Chi yu ma 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期28-45,共18页
Accurate real-time simulations of nuclear reactor circuit systems are particularly important for system safety analysis and design.To effectively improve computational efficiency without reducing accuracy,this study e... Accurate real-time simulations of nuclear reactor circuit systems are particularly important for system safety analysis and design.To effectively improve computational efficiency without reducing accuracy,this study establishes a thermal-hydraulics reduced-order model(ROM)for nuclear reactor circuit systems.The full-order circuit system calculation model is first established and verified and then used to calculate the thermal-hydraulic properties of the circuit system under different states as snapshots.The proper orthogonal decomposition method is used to extract the basis functions from snapshots,and the ROM is constructed using the least-squares method,effectively reducing the difficulty in constructing the ROM.A comparison between the full-order simulation and ROM prediction results of the AP1000 circuit system shows that the proposed ROM can improve computational efficiency by 1500 times while achieving a maximum relative error of 0.223%.This research develops a new direction and perspective for the digital twin modeling of nuclear reactor system circuits. 展开更多
关键词 Reactor system model Primary circuit Reduced-order Proper orthogonal decomposition Least-squares method
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Orbital and sinus rhabdomyosarcoma with concurrent central retinal artery occlusion:A case report
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作者 yu ma Bo Jia +3 位作者 Xiao-Juan He yue-Xia Cai Jin-Ying Chen Jing-Xiang Zhong 《World Journal of Clinical Oncology》 2024年第12期1507-1513,共7页
BACKGROUND Both rhabdomyosarcoma(RMS)and central retinal artery occlusion(CRAO)are rare medical diseases,and their simultaneous occurrence in the same patient is extraordinarily uncommon.This study presents a comprehe... BACKGROUND Both rhabdomyosarcoma(RMS)and central retinal artery occlusion(CRAO)are rare medical diseases,and their simultaneous occurrence in the same patient is extraordinarily uncommon.This study presents a comprehensive overview of the clinical manifestations,diagnostic imaging results,and therapeutic interventions of a patient with both conditions.CASE SUMMARY In this report,we present a 30-year-old male who presented with significant protrusion,pain and vision loss and was diagnosed with RMS in the orbit and sinus with CRAO.Following resection of the sinus and orbital mass and enucleation of the right eye,the patient experienced symptom improvement.CONCLUSION This article provides an in-depth analysis of the patient’s clinical manifestations,the tumor’s anatomical origin,and the etiology of CRAO.The concurrent manifestation of both RMS and CRAO is exceedingly uncommon in clinical practice. 展开更多
关键词 RHABDOMYOSARCOMA ALVEOLAR Orbital tumor Central retinal artery occlusion Vision loss Case report
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濒危药材川贝母野生变家种进展 被引量:1
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作者 肖婷 杨明豪 +5 位作者 王秋玲 吕强 郑玉清 许连城 余马 魏建和 《中国中药杂志》 北大核心 2025年第16期4483-4489,共7页
川贝母为百合科贝母属多年生草本植物的干燥鳞茎,是我国传统道地药材的典型代表,临床常用于治疗干咳、支气管哮喘等呼吸道疾病,具有重要的药用价值和较高的经济价值,在中医临床备受推崇。川贝母主要依赖野生采集,但由于过度采挖,其野生... 川贝母为百合科贝母属多年生草本植物的干燥鳞茎,是我国传统道地药材的典型代表,临床常用于治疗干咳、支气管哮喘等呼吸道疾病,具有重要的药用价值和较高的经济价值,在中医临床备受推崇。川贝母主要依赖野生采集,但由于过度采挖,其野生资源急剧减少,所有基原物种均被列入《国家重点保护野生植物名录》Ⅱ级,市场供需矛盾日益加剧。为缓解这一矛盾,川贝母的野生变家种规模化种植已成为必然趋势。然而,川贝母对生长环境要求严苛,扩繁效率低,死苗率高,栽培技术尚不成熟,严重阻碍了其产业化进程。该研究基于川贝母野生变家种过程中的繁种、育苗及药材生产状况进行调研,结合川贝母基原植物野生资源种类及分布、资源濒危状况、药材供求关系和野生变家种的发展历史及现状进行综述。结果表明,提升扩繁效率、优化种植模式及区分繁种与药材生产是推动川贝母野生变家种产业化的重要途径。该研究旨在促进川贝母野生变家种产业化进程,为珍稀濒危药用植物资源保护与可持续利用提供范式参考。 展开更多
关键词 川贝母 野生变家种 扩繁 规模化生产 种植模式
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北柴胡苗期根系发育中植物激素信号通路关键基因研究
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作者 师倩囡 莫传鑫 +8 位作者 魏桢 田林 罗亚东 李玉婵 闫明月 余马 赵军 辛超 陈华 《中草药》 北大核心 2025年第11期4019-4028,共10页
目的发掘植物激素信号通路中与北柴胡Bupleurum chinense侧根发育紧密关联的基因。方法以自组拼接的北柴胡基因组为模板,对北柴胡推广品种川北柴1号苗期根系进行有参考基因组的转录组分析,筛选参与植物激素信号转导的关键基因,利用实时... 目的发掘植物激素信号通路中与北柴胡Bupleurum chinense侧根发育紧密关联的基因。方法以自组拼接的北柴胡基因组为模板,对北柴胡推广品种川北柴1号苗期根系进行有参考基因组的转录组分析,筛选参与植物激素信号转导的关键基因,利用实时荧光定量聚合酶链式反应(real-time fluorescent quantitative polymerase chain reaction,qRT-PCR)技术验证关键基因对外源生长素处理的表达应答。结果有参转录组分析得到32259个基因,681个基因在有侧根成熟区(RO)样本中特异表达。加权基因共表达网络分析将基因分为56个模块,2个模块与主根长度和侧根数目显著相关。与侧根形成高度相关的生长素信号转导与运输通路上共发掘到88个差异基因,其中26个基因表达模式高度相关。转录组差异基因表达相关性与外源生长素处理后的基因表达结果联合分析表明,BcIAA13、BcARF19、BcSAUR55和BcSAUR72基因可能是侧根生长发育的关键基因。结论进一步揭示了在RO样本中表达量高的基因可能与侧根发育密切相关,并筛选到转录因子BcARF19与BcIAA13密切相关,其可能调控下游基因的表达,进而影响侧根的生长发育。 展开更多
关键词 北柴胡 转录组 植物激素信号转导 侧根发育 外源生长素
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Cavity-Enhanced Rydberg Atom Microwave Receiver
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作者 Bang Liu Li-Hua Zhang +11 位作者 Qi-Feng Wang yu ma Tian-yu Han Zong-Kai Liu Zheng-yuan Zhang Shi-Yao Shao Jun Zhang Qing Li Han-Chao Chen yu-Long Han Dong-Sheng Ding Bao-Sen Shi 《Chinese Physics Letters》 2025年第5期7-11,共5页
Developing microwave electric field sensing based on Rydberg atoms has received significant attention due to its unique advantages. However, achieving effective coupling between Rydberg atoms and the microwave electri... Developing microwave electric field sensing based on Rydberg atoms has received significant attention due to its unique advantages. However, achieving effective coupling between Rydberg atoms and the microwave electric field in the sensing process is a challenging problem that greatly impacts the sensitivity. To address this, we propose using a microwave resonant cavity to enhance the effective coupling between the Rydberg atoms and the microwave electric field. In our experiment, Rydberg atoms are prepared via a three-photon excitation scheme, and the electric fields are measured without and with a microwave cavity in which the vapor cell is placed inside, respectively. As a result, we achieved an 18 dB enhancement of power sensitivity by adding the cavity,which is an effective enhancement in electric field pulse signal detection. This experimental testing provides a promising direction for enhancing the sensitivity of Rydberg atomic electric field sensors and paves the way for their application in precision electric field measurements. 展开更多
关键词 rydberg atoms enhance effective coupling microwave electric field cavity enhanced microwave electric field sensing sensing process microwave resonant cavity Rydberg atoms
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Control upconversion decay dynamics from perspective of collective response
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作者 Yingdong Han yutong Pan +7 位作者 Tong Wei yu ma Xingxing Zhang Lei Jiang Kai Chen Liwei Wu Jiao Cui Chao Gao 《Journal of Rare Earths》 2025年第1期57-63,I0003,共8页
Very recently,upconversion luminescence(UCL)lifetime,as a powerful optical dimension,has attracted tremendous research interest due to its advantages of high information capacity and high photophysical stability.With ... Very recently,upconversion luminescence(UCL)lifetime,as a powerful optical dimension,has attracted tremendous research interest due to its advantages of high information capacity and high photophysical stability.With the implementation and emergence of endlessly fascinating UCL features,it is particularly meaningful to understand the photophysical mechanisms inside UCL materials to enable rational subdivision-level structure design,which is however currently far from sufficient.In this work,we take an ordinary upconversion nanoparticle as an example to prove that the UCL decay curves and corresponding lifetimes are indeed a collective response of the entire UCL system to excitations,that exhibits correlated,yet quite different properties from individual ions.A specially developed theoretical random walk model combined with an experimental lifetime control for Yb^(3+)/Er^(3+)UCL demonstrates that ene rgy diffusion principally alters the decay rate.Moreover,the different extent of the influence of energy diffusion on the emissions of ^(2)H_(11/2)/^(4)S_(3/2)(green)and ^(4)F_(9/2)(red)leads to an extremely uncommon crossover comparison of decay rates.This work provides new ideas for understanding decay dynamics and practical UCL lifetime manipulation methods. 展开更多
关键词 UPCONVERSION LIFETIME Collective response Decaycurves Random walk model Rare earths
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Enhancing interlayer hydrogen bonds of 2D Ruddlesden-Popper perovskite toward stable polarization-sensitive photodetection
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作者 Xian-Mei Zhao Li-Wei Tang +6 位作者 Yi Liu yu ma Tian Yang Hao Rong Lin-Jie Wei Jun-Hua Luo Zhi-Hua Sun 《Chinese Chemical Letters》 2025年第7期582-586,共5页
2D Ruddlesden-Popper(RP)polar perovskite,displaying the intrinsic optical anisotropy and structural polarity,has a fantastic application perspective in self-powered polarized light detection.However,the weak van der W... 2D Ruddlesden-Popper(RP)polar perovskite,displaying the intrinsic optical anisotropy and structural polarity,has a fantastic application perspective in self-powered polarized light detection.However,the weak van der Waals interaction between the organic spacing bilayers is insufficient to preserve the stability of RP-type materials.Hence,it is of great significance to explore new stable 2D RP-phase candidates.In this work,we have successfully constructed a highly-stable polar 2D perovskite,(t-ACH)_(2)PbI_(4)(1,where t-ACH^(+)is HOOC_(8)H_(12)NH_(3)^(+)),by adopting a hydrophobic carboxylate trans-isomer of tranexamic acid as the spacing component.Strikingly,strong O-H…O hydrogen bonds between t-ACH^(+)organic bilayers compose the dimer,thus decreasing van der Waals gap and enhancing structural stability.Besides,such orientational hydrogen bonds contribute to the formation of structural polarity and generate an obvious bulk photovoltaic effect in 1,which facilitates its self-powered photodetection.As predicted,the combination of inherent anisotropy and polarity leads to self-powered polarized-light detection with a high ratio of around∼5.3,superior to those of inorganic 2D counterparts.This work paves a potential way to design highly-stable 2D perovskites for high-performance optoelectronic devices. 展开更多
关键词 Polar hybrid perovskite Intermolecular interaction Strong stability Bulk photovoltaic effect Self-powered polarization light detection
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饮食-肠道微生物-脑肠轴的交互作用对情绪影响的研究进展
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作者 成杰 马宇 +1 位作者 蔡丽颖 唐启群 《世界华人消化杂志》 2025年第7期522-526,共5页
饮食-肠道微生物-脑肠轴的交互作用在情绪调节领域受到广泛关注.这一轴系构成了大脑与肠道间的复杂双向通信网络,涉及神经信号的传递、免疫反应的调节和内分泌系统的互动等多个方面.肠道微生物群通过产生短链脂肪酸和神经递质前体等代... 饮食-肠道微生物-脑肠轴的交互作用在情绪调节领域受到广泛关注.这一轴系构成了大脑与肠道间的复杂双向通信网络,涉及神经信号的传递、免疫反应的调节和内分泌系统的互动等多个方面.肠道微生物群通过产生短链脂肪酸和神经递质前体等代谢产物,对情绪产生影响.同时,饮食成分直接影响肠道微生物的组成与功能,可能进一步影响大脑健康.这一机制为通过调节饮食和微生物群管理与情绪疾病提供了新视角.未来研究需深入探索饮食-肠道微生物-脑肠轴的详细作用机制,建立标准化研究方法,并识别关键生物标志物,以促进新的预防和治疗策略的发展,改善人类情绪健康. 展开更多
关键词 饮食-肠道微生物-脑肠轴 作用机制 情绪 研究进展
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7.0T nuclear magnetic resonance evaluation of the amyloid beta(1–40) animal model of Alzheimer's disease: comparison of cytology verification 被引量:6
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作者 Lei Zhang Shuai Dong +1 位作者 Guixiang Zhao yu ma 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第4期430-435,共6页
3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer's disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain... 3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer's disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer's disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer's disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer's disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta (1-40) animal model of Alzheimer's disease. 展开更多
关键词 nerve regeneration Alzheimer's disease AΒ1-40 high-field functional magnetic resonance nuclear magnetic resonance spectroscopy NEUROPATHOLOGY N-ACETYLASPARTATE CREATINE CHOLINE hippocampus NSFC grant neural regeneration
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QTL Mapping for Important Agronomic Traits in Synthetic Hexaploid Wheat Derived from Aegiliops tauschii ssp. tauschii 被引量:6
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作者 yu ma CHEN Guo-yue +9 位作者 ZHANG Lian-quan LIU Ya-xi LIU Deng-cai WANG Ji-rui PU Zhi-en ZHANG Li LAN Xiu-jin WEI yu-ming LIU Chun-ji ZHENG You-liang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1835-1844,共10页
Aegiliops tauschii is classified into two subspecies: Ae. tauschii ssp. tauschii and Ae. tauschii ssp. strangulata. Novel genetic variations exist in Ae. tauschii ssp. tauschii that can be utilized in wheat improveme... Aegiliops tauschii is classified into two subspecies: Ae. tauschii ssp. tauschii and Ae. tauschii ssp. strangulata. Novel genetic variations exist in Ae. tauschii ssp. tauschii that can be utilized in wheat improvement. We synthesized a hexaploid wheat genotype(SHW-L1) by crossing an Ae. tauschii ssp. tauschii accession(AS60) with a tetraploid wheat genotype(AS2255). A population consisting of 171 F8 recombinant inbred lines was developed from SHW-L1 and Chuanmai 32 to identify QTLs associated with agronomic traits. A new genetic map with high density was constructed and used to detect the QTLs for heading date, kernel width, spike length, spikelet number, and thousand kernel weight. A total of 30 putative QTLs were identified for five investigated traits. Thirteen QTLs were located on D genomes of SHW-L1, six of them showed positive effect on agronomic traits. Chromosome region flanked by wPt-6133–wPt-8134 on 2D carried five environment-independent QTLs. Each QTL accounted for more than 10% phenotypic variance. These QTLs were highly consistent across environments and should be used in wheat breeding. 展开更多
关键词 genetic map QTL DART agronomic traits synthetic wheat Aegilops tauschii ssp.tauschii
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Lattice Boltzmann method for simulation of time-dependent neutral particle transport 被引量:3
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作者 Ya-Hui Wang Li-Ming Yan +1 位作者 Bang-Yang Xia yu ma 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第3期74-84,共11页
In this paper, a novel model is proposed to investigate the neutron transport in scattering and absorbing medium. This solution to the linear Boltzmann equation is expanded from the idea of lattice Boltzmann method(LB... In this paper, a novel model is proposed to investigate the neutron transport in scattering and absorbing medium. This solution to the linear Boltzmann equation is expanded from the idea of lattice Boltzmann method(LBM) with the collision and streaming process. The theoretical derivation of lattice Boltzmann model for transient neutron transport problem is proposed for the first time.The fully implicit backward difference scheme is used to ensure the numerical stability, and relaxation time and equilibrium particle distribution function are obtained. To validate the new lattice Boltzmann model, the LBM formulation is tested for a homogenous media with different sources, and both transient and steady-state LBM results get a good agreement with the benchmark solutions. 展开更多
关键词 Transient NEUTRON transport LATTICE BOLTZMANN method Linear BOLTZMANN equation
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STRESS-INDUCED POLYMER DEFORMATION IN SHEAR FLOWS 被引量:2
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作者 Juan Li Yi-jing Nie +1 位作者 yu ma 胡文兵 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第11期1590-1598,共9页
By means of dynamic Monte Carlo simulation of bulk lattice polymers in Couette shear flow, it was demonstrated that in addition to velocity gradient the constant driving forces acting as the activation aspect of shear... By means of dynamic Monte Carlo simulation of bulk lattice polymers in Couette shear flow, it was demonstrated that in addition to velocity gradient the constant driving forces acting as the activation aspect of shear stresses can also raise polymer deformation. Moreover, enhancing driving forces in a flow without any velocity gradient can reproduce non- Newtonian fluid behaviors of long-chain polymers. The simulations of Poiseuille shear flow with a gradient of shear stresses show that, the velocity gradient dominates small deformation in the flow layers of low shear stresses, while the shear stress dominates large deformation in the flow layers of high shear stresses. This result implies that the stress-induced deformation could be mainly responsible for the occurrence of non-Newtonian fluid behaviors of real polymers at high shear rates. 展开更多
关键词 Polymer deformation Monte Carlo simulation Shear flow.
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NEW OPTICALLY ACTIVE AROMATIC POLYIMIDES Ⅱ: SYNTHESIS AND PROPERTIES OF OPTICALLY ACTIVE AROMATIC POLYIMIDE BASED ON (R)-(+)-2, 2′-BIS (2-TRIFLUORO-4-AMINOPHENOXY)-1, 1′-BINAPHTHYL 被引量:1
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作者 Qi-ding Mi yu ma +1 位作者 Lian-xun Gao Meng-xian Ding Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun 130022, China Department of Chemistry, Peking University, Beijing 100871 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第1期87-90,共4页
Optically active (R)-(+)-2, 2' -bis(2 -trifluoro-4 -aminophenoxy)- 1, 1' -binaphthyl was prepared from1, 1'-bi-2-naphthol. The optically active aromatic polyimide was also successfully synthesized. This ne... Optically active (R)-(+)-2, 2' -bis(2 -trifluoro-4 -aminophenoxy)- 1, 1' -binaphthyl was prepared from1, 1'-bi-2-naphthol. The optically active aromatic polyimide was also successfully synthesized. This newpolymer has good solubility, thermal stability etc. Its specific rotation was found to be +174°, and itschiroptical property was also studied. 展开更多
关键词 Optical activity 1 1′-Bi-2-naphthol Polyimide
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Enantioseparation of 3-chlorophenylglycine enantiomers using Mandyphos-Pd as chiral extractant
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作者 Xiong Liu Shuhuan Chen +1 位作者 yu ma Wenjie Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第5期96-103,共8页
Chiral extractant plays a key role in chiral extraction,and considerable efforts have been undertaken for the development of new and efficient chiral extractants in recent years.This work demonstrated for the first ti... Chiral extractant plays a key role in chiral extraction,and considerable efforts have been undertaken for the development of new and efficient chiral extractants in recent years.This work demonstrated for the first time that chiral ferrocenyl diphosphine ligand(Mandyphos-Pd)had considerable ability to enantioseparate 3-Chlorophenylglycine enantiomers with separation factor(α)of 2.64.Mandyphos-Pd concentration and pH had significant influences on enantioselectivity,while operating temperature showed less influence.The extraction experiments can be performed at room temperature(20℃)which had the advantage of energy saving.After optimization,the highest performance factor(pf,0.08376)was obtained at the condition of pH 7.8 and Mandyphos-Pd concentration 1.2 mmol·L^(-1).According to the experimental results,the possible recognition mechanism was discussed. 展开更多
关键词 ENANTIOSEPARATION Mandyphos 3-Chlorophenylglycine Response surface method RECOGNITION mechanism
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Nonreciprocal properties of 1D magnetized plasma photonic crystals with the Fibonacci sequence
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作者 yu ma Hao ZHANG +2 位作者 Haifeng ZHANG Ting LIU Wenyu LI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第1期5-12,共8页
In this paper, the nonreciprocal properties of a novel kind of 1D magnetized plasma photonic crystals(MPPCs) with the Fibonacci sequence are investigated. The isolation of the proposed 1D MPPCs is also used to analyze... In this paper, the nonreciprocal properties of a novel kind of 1D magnetized plasma photonic crystals(MPPCs) with the Fibonacci sequence are investigated. The isolation of the proposed 1D MPPCs is also used to analyze the nonreciprocal properties. Compared to the conventional 1D MPPCs with periodic structure, the nonreciprocal performance can be significantly improved.The effects of several parameters of the proposed 1D MPPCs on the nonreciprocal properties are studied by the transfer matrix method, which includes the incident angle, order of the Fibonacci sequence, plasma frequency, plasma cyclotron frequency and plasma filling factor. The obtained results show that the nonreciprocal propagation properties can be improved by increasing the values of the plasma cyclotron frequency and incident angle, but they will worsen by blindly increasing the order of the Fibonacci sequence, plasma frequency and filling factor of plasma.The peaks of transmittance also are obviously reduced. In addition, the value of isolation will increase with increasing the incident angle, order of Fibonacci sequence, plasma frequency and plasma filling factor. However, when the plasma cyclotron frequency is increased, the value of isolation will be increased at lower frequencies, but is almost unchanged at higher frequencies. 展开更多
关键词 MAGNETIZED plasma PHOTONIC CRYSTALS TRANSFER matrix method nonreciprocal properties QUASI-PERIODIC structure ISOLATION
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Molecular Related Indexes Assessment and Traits Correlation Analysis of Turbot(Scophthalmus maximus L.) by Using SSR Marker Correlation Coefficient in Turbot
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作者 yu ma yulong HU +1 位作者 Liyong XU Weiji WANG 《Agricultural Science & Technology》 CAS 2014年第6期895-900,共6页
Five molecular related indexes: MOL, SIM, d2, H0and PIC of 15 turbot parent pairs were estimated by using 10 SSR loci, which were used in correlation analysis with growth traits, DIL and DIW, of family filial from tho... Five molecular related indexes: MOL, SIM, d2, H0and PIC of 15 turbot parent pairs were estimated by using 10 SSR loci, which were used in correlation analysis with growth traits, DIL and DIW, of family filial from those 15 parent pairs.DIL and DIW were regressed on the MOL, SIM, d2, H0and PIC. Results showed MOL of five SSR loci(12, 17, 24, 81 and 85) and SIM of five loci(17, 21, 24, 81and 85) all shared significant positive correlation with DIL(r=0.482, P=0.035 and r=0.479, P=0.035, respectively); H0of six SSR loci(11, 17, 21, 24, 26 and 85) had significant positive correlation with DIW(r=0.551, P=0.017); PIC of two SSR loci(9and 26) had significant positive(r=0.519, P=0.024) correlation with DIL, while that and of four loci(17, 24, 27 and 85) had significant negative correlation(r=-0.519,P=0.024), with DIL. This present study suggested that filial growth expression could be predicted by using molecular related indexes in turbot breeding practice, and the accuracy of prediction depends on more SSR loci, especially associated with QTL. 展开更多
关键词 TURBOT MICROSATELLITE Molecular related indexes Heterosis prediction
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An Application of Canny Edge Detection Algorithm to Rail Thermal Image Fault Detection
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作者 Libo Cai yu ma +2 位作者 Tangming yuan Haifeng Wang Tianhua Xu 《Journal of Computer and Communications》 2015年第11期19-24,共6页
The paper discusses an application for rail track thermal image fault detection. In order to get better results from the Canny edge detection algorithm, the image needs to be processed in advance. The histogram equali... The paper discusses an application for rail track thermal image fault detection. In order to get better results from the Canny edge detection algorithm, the image needs to be processed in advance. The histogram equalization method is proposed to enhance the contrast of the image. Since a thermal image contains multiple parallel rail tracks, an algorithm has been developed to locate and separate the tracks that we are interested in. This is accomplished by applying the least squares linear fitting technique to represent the surface of a track. The performance of the application is evaluated by using a number of images provided by a specialised company and the results are essentially favourable. 展开更多
关键词 FAULT DETECTION RAIL Thermal Image CANNY Edge DETECTION Linear Least SQUARES
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