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Nuclear Starburst Activity in the Seyfert 2 Galaxy NGC 2273

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Chinese Journal of Astronomy and Astrophysics 2003年第3期3卷 203-211页

作者： Qiu-Sheng Gu, Lei shi, shi-Jun Lei, wen-hao Liu and Jie-hao Huang Department of Astronomy, Nanjing University, Nanjing 210093 qsgu@*** Department of Astronomy Nanjing University Nanjing 210093

We present spectrophotometric results of the Seyfert 2 galaxy NGC 2273. Thepresence of high-order Balmer absorption lines (H8, H9, H10) and weak equivalent widths of CaII Kλ3933, CN λ4200, G-band λ4300 and MgIb λ5173 clearly indicate recent star-forming activity inthe nuclear region. Using a simple stellar population synthesis model, we find that for the bestfit, the contributions of a power-law featureless continuum, an intermediate-age (～ 10~8 yr) and anold (> 10~9 yr) stellar population to the total light at the reference normalization wavelength are10.0%, 33.4% and 56.6%, respectively. The existence of recent starburst activity is also consistentwith its high far-infrared luminosity (log L_(FIR.)/L☉ = 9.9), its infrared color indexes[α(25,60) = ― 1.81 and α(60,100) = ― 0.79, typical values for Seyfert galaxies withcircumnuclear starburst], and its q-value (2.23, ratio of infrared to radio flux, very similar tothat of normal spirals and starburst galaxies). Byrd et al. have suggested that NGC 2273 might haveinteracted with NGC 2273B in less than 10~9 yr ago, so the starburst activity in this galaxy couldhave been triggered by tidal interaction, as indicated in recent numerical simulations.

关键词： galaxies: seyfert galaxies: starburst galaxies: stellar content

解冻卵裂期胚胎养成囊胚行植入前遗传学检测二次冷冻复苏移植后临床结局

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生殖医学杂志 2024年第7期33卷 873-877页

作者：李晓芳师娟子施文浩柏海燕西北妇女儿童医院生殖中心西安710003

目的回顾性评估解冻卵裂期胚胎养成囊胚后进行活检,再次冷冻移植后临床及新生儿结局,以期为临床医生和患者提供参考数据。方法收集2017年1月至2022年10月于西北妇女儿童医院生殖中心接受解冻卵裂期胚胎养成囊胚后进行活检,再次解冻移... 详细信息

目的回顾性评估解冻卵裂期胚胎养成囊胚后进行活检,再次冷冻移植后临床及新生儿结局,以期为临床医生和患者提供参考数据。方法收集2017年1月至2022年10月于西北妇女儿童医院生殖中心接受解冻卵裂期胚胎养成囊胚后进行活检,再次解冻移植治疗的患者的冻融胚胎移植周期为实验组(n=13),并将女方新鲜周期取卵时年龄、移植囊胚级别、胚胎植入前遗传学诊断的指证以及分类作为匹配因素,按照1∶3配对,选取同周期新鲜囊胚活检、解冻后移植的患者作为对照组(n=39)。比较两组患者的临床基线资料、妊娠结局以及新生儿结局。结果两组患者临床基本资料、妊娠率以及活产率均无统计学差异(P>0.05),两组产科及新生儿结局亦无显著性差异(P>0.05)。两组患者均未报道重大产科并发症和新生儿畸形。结论将冻存的卵裂期胚胎解冻后培养至囊胚期进行活检,行胚胎植入前遗传学检测,冷冻后再次复苏行冻融移植周期的妊娠率、活产率及新生儿结局与新鲜囊胚活检后进行冻融移植无明显差异,可以为患者提供更多的选择。

关键词：解冻卵裂期胚胎胚胎植入前遗传学检测病例匹配对照研究活产率二次冷冻

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： wen-hao Zeng shi-Dan Zhu Ying-Hua Luo Wei shi Yong-Qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Matrix orthogonal polynomials,non-abelian Toda lattices,and Bäcklund transformations

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Science China Mathematics 2024年第9期67卷 2071-2090页

作者： shi-hao Li Department of Mathematics Sichuan UniversityChengdu 610064China

A connection between matrix orthogonal polynomials and non-abelian integrable lattices is investigated in this *** normalization factors of matrix orthogonal polynomials expressed using quasideterminants are shown to be the solutions to the non-abelian Toda lattice in semi-discrete and full-discrete ***,with a moment modification method,we demonstrate that the B¨acklund transformation of the non-abelian Toda lattice given by Popowicz(1983)is equivalent to the non-abelian Volterra lattice,whose solutions can be expressed using quasi-determinants as well.

关键词： matrix orthogonal polynomial non-abelian Toda lattice Backlund transformation quasideterminant technique

Experimental observation of spontaneous symmetry breaking in a quantum phase transition

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 34-39页

作者： wen Ning Ri-Hua Zheng Jia-hao Lu Fan Wu Zhen-Biao Yang shi-Biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350108China Hefei National Laboratory Hefei 230088China

Spontaneous symmetry breaking(SSB)plays a central role in understanding a large variety of phenomena associated with phase transitions,such as superfluid and *** far,the transition from a symmetric vacuum to a macroscopically ordered phase has been substantially *** process bridging these two distinct phases is critical to understanding how a classical world emerges from a quantum phase transition,but so far remains unexplored in *** here report an experimental demonstration of such a process with a quantum Rabi model engineered with a superconducting *** move the system from the normal phase to the superradiant phase featuring two symmetry-breaking field components,one of which is observed to emerge as the classical *** results demonstrate that the environment-induced decoherence plays a critical role in the SSB.

关键词： quantum phase transition Rabi model spontaneous symmetry breaking superconducting circuit Schrodinger cat states

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植物抗氧化活性成分研究进展

广州化工 2024年第10期52卷 7-10页

作者：史文灏张立新高品一李丹琦刘学贵沈阳化工大学制药与生物工程学院辽宁沈阳110142 沈阳化工大学功能分子研究所辽宁沈阳110142 辽宁省绿色功能分子设计与开发重点实验室辽宁沈阳110142 硼镁资源开发与精细化工技术国家地方联合工程实验室辽宁沈阳110142

过量活性氧会造成氧化应激,使食品、化妆品等发生不同程度的氧化而腐败变质。抗氧化剂的使用可以有效地减轻由过量活性氧带来的不良影响,但合成抗氧化剂的毒副作用较大,研究人员开始关注低毒高效的天然抗氧化剂。本综述对抗氧化剂的分... 详细信息

过量活性氧会造成氧化应激,使食品、化妆品等发生不同程度的氧化而腐败变质。抗氧化剂的使用可以有效地减轻由过量活性氧带来的不良影响,但合成抗氧化剂的毒副作用较大,研究人员开始关注低毒高效的天然抗氧化剂。本综述对抗氧化剂的分类、植物提取物抗氧化活性成分、作用机制进行系统阐述,并介绍作者课题组目前在研究植物抗氧化成分研究方面的成果。

关键词：抗氧化活性成分抗氧化剂作用机制

Effect of Guanxin Danshen Dripping Pills on Coronary Heart Disease Comorbid with Depression or Anxiety: The ADECODE-Real World Study

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Chinese Journal of Integrative Medicine 2024年第5期30卷 443-448页

作者： WU shi-hao shi Wei-qi LI Yu-hang LIU Ru-hui HU Da-yi ZHENG Li-qiang MA wen-lin Department of Geriatric Medicine Tongji HospitalSchool of MedicineTongji UniversityShanghai 200065China Department of Cardiology Tongji HospitalSchool of MedicineTongji UniversityShanghai 200065China Department of Cardiology Peking University People's HospitalBeijing 100044China School of Public Health Shanghai Jiao Tong UniversityShanghai 200030China

Objective: To evaluate the efficacy of Guanxin Danshen Dripping Pill(GXDSDP) in treating anxiety and depression in patients with coronary heart disease(CHD). Methods: A total of 1,428 patients diagnosed with CHD screened for anxiety, depression, and quality of life(QOL) at baseline received 0.4 g of GXDSDP treatment 3 times per day and returned for monthly reassessment. Patients were recruited after stable treatment for CHD and received assessment of General Anxiety Disorder-7(GAD-7), Patient Health Questionnaire-9(PHQ-9), and Seattle Angina Questionnaire(SAQ) for evaluating anxiety, depression, and *** were followed up 3 times, once every 4 weeks, during outpatient visits for 12 weeks. Results: At the third follow-up(F3), the anxiety symptom of 63.79%(673/1,055) of the patients improved to sub-clinical level, and the GAD-7 score improved significantly(8.11 vs. 3.87, P<0.01);57.52%(585/1,017) patients' depressive symptoms improved to sub-clinical level, with a significant improvement in PHQ-9 score(8.69 vs. 4.41, P<0.01) at F3. All aspects of QOL significantly improved at the end of treatment compared to those at baseline(all P<0.01) as assessed by SAQ: physical limitation(31.17 vs. 34.14), anginal stability(2.74 vs. 4.14), anginal frequency(8.16vs. 9.10), treatment satisfaction(13.43 vs. 16.29), and disease perception(8.69 vs. 11.02). Conclusions: A fixed dosage of GXDSDP may be a potential treatment option for CHD patients comorbid with anxiety or depression.(Registration No. ChiCTR2100051523)

关键词： Guanxin Danshen Dripping Pill coronary heart disease depression anxiety quality of life Chinese medicine

Isotopic insights on quantitative assessments of interaction of eco-hydrological processes in multi-scale karst watersheds

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International Soil and Water Conservation Research 2024年第1期12卷 156-170页

作者： Zhuo hao Yang Gao Qingwen Zhang wen wen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Humanities and Social Sciences Beijing Institute of TechnologyBeijing100081China

The dynamics of hydrological processes and the storage mechanisms of karst water resources are the most important issues in karst *** impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly *** this study,high-frequency continuous monitoring in multi-scale karst watersheds in Southwest China combined the approaches of water isotopes and the hybrid single-particle lagrangian integrated trajectory(HYSPLIT)model to identify the recharge mechanisms between atmospheric vapor,rainfall,surface water,and groundwater,and to reveal the interaction of eco-hydrological *** dominant moisture sources in Puding(PD)County were the Indian Ocean(43-69%)and local moisture(24-33%).Theδ^(18)O and deuterium excess(d-excess)values showed a positive correlation indicating that secondary or sub-cloud evaporation was prominent in the wet *** water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across *** to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater *** Chenqi stream replenished the Houzhai River mainly in the form of groundwater,with percentages ranging from 38.1 to 93.5%in the wet season,and 47.8-80.1%in the dry *** the Houzhai outlet,surface water and groundwater interconverted frequently with a percentage of 45.6-49.1%.We believe this is the first systematic study to quantify the supply relationship between water vapor transport,rainfall,surface water and groundwater in the Chinese karst zone,making a significant move forward in the field of karst hydrological processes and improving the efficiency of water resource evaluation and management.

关键词： Stable isotope Moisture sources Water cycle Karst watersheds

Weakly Approximate Diagonalization of Homomorphisms into Finite von Neumann Algebras

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2187-2194页

作者： wen Hua QIAN Jun hao SHEN wen Ming WU School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematics and Statistics University of New HampshireDurhamNH 03824USA

Let A be a unital C^(∗)-algebra and B a unital C^(∗)-algebra with a faithful traceτ.Let n be a positive *** give the definition of weakly approximate diagonalization(with respect toτ)of a unital homomorphismφ:A→Mn(B).We give an equivalent characterization of McDuff Ⅱ_(1) *** show that,if A is a unital nuclear C^(∗)-algebra and B is a type Ⅱ_(1) factor with faithful traceτ,then every unital^(∗)-homomorphism φ:A→M_(n)(B)is weakly approximately *** B is a unital simple infinite dimensional separable nuclear C^(∗)-algebra,then any finitely many elements in Mn(B)can be simultaneously weakly approximately diagonalized while the elements in the diagonals can be required to be the same.

关键词： Weakly approximately diagonalizable McDuff factors nuclear hyperfinite