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SnSi nanocrystals of zinc-blende structure in a Si matrix

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Nano Research 2015年第12期8卷 3905-3911页

作者： alexander Tonkikht Andrey Klavsyuk Nikolay Zakharov alexander Saletsky Peter Werner Max Planck Institute of Microstructure Physics Halle(Saale) 06120 Germany Faculty of Physics Moscow State University Moscow 119991 Russian Federation

A zinc-blende （sphalerite） crystallographic structure of SnSi nanocrystals generated by molecular-beam epitaxy is observed by electron microscopy techniques in a Si matrix. Ab initio density-functional modeling reveals a stabilizing effect of the Si matrix, which results in the lowest formation enthalpy of SnSi nanocrystals having the unexpected zinc-blende structure. Such nanocrystals could be applied in Si photonics to function as non-centrosymmetric media for the nonlinear optical process of second harmonic generation.

关键词： epitaxy density functional theory zinc-blende Si-Sn alloy

Improved proper motion determinations for 15 open clusters based on the UCAC4 catalog

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Research in Astronomy and Astrophysics 2016年第7期16卷 39-46页

作者： alexander Kurtenkov Nadezhda Dimitrova alexander Atanasov Teodor D.Aleksiev Department of Astronomy University of Sofia5 James Bourchier Blvd.1164 SofiaBulgaria Institute of Astronomy and National Astronomical Observatory Bulgarian Academy of Sciences72 Tsarigradsko Shose Blvd.1784 SofiaBulgaria Anglo-American School of Sofia 1 Siyanie Str.1138 SofiaBulgaria Geo Milev High School of Mathematics Storgozia5802 PlevenBulgaria Sofia High School of Mathematics 61 Iskar Str.1000 SofiaBulgaria

The proper motions of 15 nearby（d 〈 1 kpc） open clusters（OCs） were recalculated using data from the UCAC4 catalog. Only evolved or main sequence stars inside a certain radius from the center of the cluster were used. The results significantly differ from the ones presented by Dias et al.（2014）. This could be explained by a different approach in which we take the field star contamination into account. The present work aims to emphasize the importance of applying photometric criteria for the calculation of OC proper motions.

关键词： proper motions Galaxy open clusters and associations general

How big can a walking fish be?A theoretical inference based on observations on four land-dwelling fish genera of South Vietnam

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Integrative Zoology 2022年第5期17卷 849-878页

作者： alexander N.KUZNETSOV Borissiak Paleontological Institute Russian Academy of SciencesMoscowRussia

Comparative study of terrestrial locomotion of 4ﬁsh genera including Anabas,Channa,Clarias,and Monopterus,was performed in experimental setting with the substrate surface of wet *** special adaptations for terrestrial locomotion were ***ﬁsh uses for propulsion on land what it already ***-shaped Monopterus crawls by body undulations in a serpentine or sidewinding technique,the latter of which was not previously observed beyond *** other 3ﬁsh genera walk by body oscillations using stiff appendages as *** they are located anteriorly,as the serrate operculum in Anabas and the preaxial spine of the pectoralﬁn in Clarias,the propulsion is termed prolocomotor,when posteriorly,as the spiny analﬁn in Channa—*** is the heaviestﬁsh walking out of water in our days,quite comparable in size withﬁrst Devonian tetrapods Acan-thostega and Tulerpeton.A theoretical calculation is suggested for the upper size limit of aﬁsh capable of terrestrial walking without special locomotor *** should be roughly 20 cm in the vertical dimension of the trunk,which is just a little above the known size of Devonian tetrapodomorphﬁshes Panderichthys and *** metalocomotor walking technique of Channa is suggested as the closest extant model for terrestrial locomotion at theﬁsh-tetrapod *** major difference is that the metalocomotor propulsor in Channa is represented by the analﬁn,while in tetrapodomorphs by the pelvicﬁ*** sprawled pelvicﬁns were advantageous in respect of reduced requirement for side-to-side tail swinging.

关键词： ﬁsh-tetrapod transition metalocomotor propulsion prolocomotor propulsion snakehead

Statistical Estimation of the Shannon Entropy

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Acta Mathematica Sinica,English Series 2019年第1期35卷 17-46页

作者： alexander BULINSKI Denis DIMITROV Steklov Mathematical Institute of Russian Academy of Sciences and Department of Mathematics and Mechanics Lomonosov Moscow State UniversityMoscow 119234Russia

The behavior of the Kozachenko–Leonenko estimates for the(differential) Shannon entropy is studied when the number of i.i.d. vector-valued observations tends to infinity. The asymptotic unbiasedness and L^2-consistency of the estimates are established. The conditions employed involve the analogues of the Hardy–Littlewood maximal function. It is shown that the results are valid in particular for the entropy estimation of any nondegenerate Gaussian vector.

关键词： Shannon differential entropy Kozachenko-Leonenko estimates Hardy-Littlewood maxi-mal function analogues asymptotic unbiasedness and L^2-consistency Gaussian vectors

绿原酸通过减轻心肌细胞铁死亡改善心力衰竭（英文）

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Journal of Traditional Chinese Medical Sciences 2024年第2期 191-198页

作者：黄凯李芳赫唐家杨普海崟 Sukhorukov,Vasily Orekhov,alexander N. 郭淑贞北京中医药大学中医学院俄罗斯医学科学院病理生理学研究所血管病理学实验室

目的：绿原酸（CGA）是一种普遍存在于传统中药和食物中的多酚类化合物，包括金银花、杜仲叶、茶和咖啡。本文的目的是阐明绿原酸对心肌细胞铁死亡和心力衰竭的影响。方法：我们通过运用主动脉缩窄（TAC）诱导的心力衰竭小鼠模型，评估... 详细信息

目的：绿原酸（CGA）是一种普遍存在于传统中药和食物中的多酚类化合物，包括金银花、杜仲叶、茶和咖啡。本文的目的是阐明绿原酸对心肌细胞铁死亡和心力衰竭的影响。方法：我们通过运用主动脉缩窄（TAC）诱导的心力衰竭小鼠模型，评估了绿原酸对心脏功能的影响，具体指标包括左室射血分数（LVEF）、分数缩短（LVFS）、舒张末期容积（LVEDV）、收缩末期容积（LVESV）、收缩末期直径（LVESD）和舒张末期直径（LVEDD）。同时建立了异丙肾上腺素（ISO）诱导的H9c2心肌细胞模型，并用不同浓度的绿原酸进行干预。为了评估绿原酸对心肌细胞铁死亡的影响，我们检测了细胞活性，并使用荧光染色评估了细胞内活性氧（ROS）、亚铁离子（Fe2+）和脂质过氧化物的水平。为了明确绿原酸调控铁死亡的信号通路，我们使用western blot检测了H9c2心肌细胞和小鼠心肌组织中铁死亡生物标志物的表达，如溶质载体家族7成员11(SLC7A11)和谷胱甘肽过氧化物酶4(GPX4)。结果：绿原酸显著增强了小鼠心脏功能指标，如LVEF、LVFS、LVEDV、LVESV、LVESD和LVEDD。异丙肾上腺素诱导的H9c2心肌细胞显示出降低的细胞活性及升高的ROS水平、Fe2+含量和脂质过氧化水平，然而，绿原酸显著改善了这些变化。此外，在H9c2心肌细胞和TAC小鼠心肌组织中，绿原酸增加铁死亡相关的蛋白表达，如SLC7A11和GPX4。结论：绿原酸具有通过SLC7A11/GPX4信号通路增强心脏功能，减少心肌细胞中的脂质过氧化、ROS水平和心肌细胞铁死亡的作用。这些结果为绿原酸的临床应用和心力衰竭的治疗提供了新的见解。

关键词：绿原酸心力衰竭铁死亡 H9c2心肌细胞中医药

Examples of unbounded homogeneous domains in complex space

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Science China Mathematics 2005年第Z1期48卷 248-261页

作者： Michael Eastwood alexander Isaev Department of Pure Mathematics University of Adelaide South Australia 5005AustraliaDepartment of Mathematics The Australian National UniversityCanberraACT 0200Australia

We present several examples of homogeneous domains in complex space that do not have bounded realisations. The domains are equivalent to tubes over affinely homogeneous domains in real space.

关键词： homogeneous unbounded domains.

Hebbian plasticity:the elusive missing link at the heart of Alzheimer’s disease pathogenesis?

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Neural Regeneration Research 2023年第1期18卷 123-124页

作者： alexander F.Jeans Department of Pharmacology University of OxfordOxfordUK

The amyloid cascade hypothesis of Alzheimer’s pathogenesis:The amyloid cascade hypothesis of Alzheimer’s disease(AD)pathogenesis will shortly celebrate its thirtieth birthday(Hardy and Higgins,1992).Based on abundant genetic and biochemical evidence,it proposes that deposition of the amyloid-β(Aβ)peptide in brain parenchyma is an essential upstream trigger in AD pathogenesis that drives a cascade of events,specifically including the recruitment and pathological hyper-phosphorylation of the micro-tubule-associated protein tau,that culminate in derangement of synaptic function and,eventually,neuronal death.

关键词： pathogenesis Alzheimer eventually

Analysis of the X-ray emission of OB stars II: B stars

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Research in Astronomy and Astrophysics 2019年第8期19卷 143-150页

作者： Elizaveta Ryspaeva alexander Kholtygin Crimean Astrophysical Observatory NauchnyCrimeaRussia Saint-Petersburg State University Saint-PetersburgRussia Institute of Astronomy Russian Academy of SciencesRussia

This paper is the second part of an investigation into the mechanism for the origin of X-rays in early-type stars. Archival X-ray observations of 25 B stars, obtained by the XMM-Newton satellite, are analysed. We check two hypotheses on the origin of X-ray emission: the Magnetically Confined Wind Shock Model(MCWS) and Pollock’s paradigm. For all studied stars, the mean ratio of the half widths at half maximum to the terminal velocities appears to be R ≈ 0.15-0.20 in contradiction to Pollock’s hypothesis that R ≈ 0.5. We checked three possible consequences of the MCWS model: correlations between the hardness of the X-ray spectra for B stars and terminal wind velocities, mass loss rates and magnetic *** was shown that such correlations are marginal or even absent both for magnetic and non-magnetic B stars.

关键词： stars:early-type stars:spectra:X-ray

Loss and Damage as an Alternative to Resilience and Vulnerability?Preliminary Reflections on an Emerging Climate Change Adaptation Discourse

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International Journal of Disaster Risk Science 2014年第1期5卷 88-93页

作者： alexander Fekete Patrick Sakdapolrak Risk and Crisis Management Section Cologne University of Applied Sciences50679 CologneGermany Department of Geography University of Bonn53115 BonnGermany

One relatively novel way of assessing the characteristics and limitations of resilience and vulnerability(R&V)is undertaken in this article by investigating a growing alternative paradigm—loss and damage(L&D)*** idea of L&D as an emerging policy may be surprising to many in the disaster risk management community,and so we first outline the origins of this trend,and then explore the potential benefits and pitfalls of adopting *** short article represents our preliminary opinions and observations regarding this reintroduction of a longestablished *** also present results from a very brief peer-group survey on some of the first immediate reactions towards L&D *** this early stage,this article cannot offer a full-fledged analysis,but our reflections may serve as a starting point to encourage further discussion.

关键词： Climate change adaptation Loss and damage Resilience Vulnerability