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Magnetic cycles of Sun-like stars with different levels of coronal and chromospheric activity——comparison with the Sun

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Research in Astronomy and Astrophysics 2016年第9期16卷 123-136页

作者： elena Shimanovskaya Vasiliy Bruevich elena Bruevich Sternberg Astronomical Institute Moscow State University

The atmospheric activity of the Sun and Sun-like stars is analyzed involving observations from the HK-project at the Mount Wilson Observatory, the California and Carnegie Planet Search Program at the Keck and Lick Observatories and the Magellan Planet Search Program at the Las Campanas Observatory. We show that for stars of E G and K spectral classes, the cyclic activity, similar to the 11-yr solar cycle, is different： it becomes more prominent in K-stars. Comparative study of Sun-like stars with different levels of chromospheric and coronal activity confirms that the Sun belongs to stars with a low level of chromospheric activity and stands apart among these stars by its minimum level of coronal radiation and minimum level of variations in photospheric flux.

关键词： Sun activity -- Sun-like stars activity

Singular Integrals with Bilinear Phases

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Acta Mathematica Sinica,English Series 2006年第1期22卷 251-260页

作者： elena PRESTINI Dipartimento di Matematica Universita di Roma 'Tor Vergata' Roma 00133 Italy

We prove the boundedness from Lp（T2） to itself, 1 〈 p 〈∞, of highly oscillatory singular integrals Sf（x, y） presenting singularities of the kind of the double Hilbert transform on a non-rectangular domain of integration, roughly speaking, defined by ｜y′｜〉｜x′｜, and presenting phases λ（Ax ＋ By） with 0≤ A, B ≤ 1 and λ≥ 0. The norms of these oscillatory singular integrals are proved to be independent of all parameters A1 B and A involved. Our method extends to a more general family of phases. These results are relevant to problems of almost everywhere convergence of double Fourier and Walsh series.

关键词： Hardy-Littlewood maximal function Maximal Hilbert transform Maximal Carleson operator Oscillatory singular integrals a.e. convergence of double Fourier series

Deciphering the presence of axial-planar veins in tectonites

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Geoscience Frontiers 2019年第6期10卷 2101-2115页

作者： elena Druguet Departament de Geologia Universitat Autonoma de Barcelona

Veins and dikes are often oriented subparallel to the axial surfaces of folds in the adjacent layered or foliated *** implies an awkward situation,since veins would lay in planes close-to-parallel to the maximum stretching axis.A series of geometric models have been conceived in order to gain insight into the possible mechanisms for their *** models are based on the analysis of a varied selection of field structures and on the review of similar structures in the existing literature.A first categorization consists on distinguishing between axial-planar veins achieved by either progressive or polyphase *** models of axial-planar veins resulting from progressive deformation are described and discussed:(1) fold-related veins associated with the standard folding mechanisms,(2) fracture arrays localized along the short limbs of folds(asymmetric fold-related veins),(3) folds associated with rotation of extension veins(vein-related folds),(4) high strain and transposition of early veins,and(5) high strain and late veins parallel to axial planar foliations(axial planar foliation-related veins).The axial planar geometry is achieved through variable amounts of progressive rotational strain,except in model 5,in which the co-planarity is acquired at the time of vein *** possibility for axial-planar veins to have developed in two distinct phases in the context of polyphase or polyorogenic tectonics has also been explored and *** study contributes to a better understanding of the intriguing interplays between deformation,metamorphic and magmatic processes in orogenic belts.

关键词： Dike Fold Fracture Metamorphic rock Migmatite Shear

Plant hormesis and Shelford’s tolerance law curve

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Journal of Forestry Research 2021年第5期32卷 1789-1802页

作者： elena A.Erofeeva Department of Ecology Lobachevsky State University of Nizhny Novgorod23 Gagarina PrNizhni NovgorodRussian Federation 603950

Shelford’s law of tolerance is illustrated by a bell-shaped curve depicting the relationship between environmental factor/factors’intensity and its favorability for species or *** is a fundamental basis of ecology when considering the regularities of environment impacts on living systems,and applies in plant biology,agriculture and forestry to manage resistance to environmental limiting factors and to enhance *** recent years,the concept of hormesis has been increasingly used to study the dose-response relationships in living organisms of different complexities,including *** requires the need for an analysis of the relationships between the hormetic dose-response model and the classical understanding of plant reactions to environments in terms of Shelford’s law of *** paper analyses various dimensions of the relationships between the hormetic model and Shelford’s tolerance law curve under the influence of natural environmental factors on plants,which are limiting for plants both in deficiency and *** analysis has shown that Shelford’s curve and hormetic model do not contradict but instead complement each *** hormetic response of plants is localized in the stress zone of the Shelford’s curve when adaptive mechanisms are disabled within the ecological *** the same time,in a species range,the ecological optimum is the most favorable combination of all or at least the most important environmental factors,each of which usually deviates slightly from its optimal *** mechanisms cannot be completely disabled in the optimum,and hormesis covers optimum and stress *** can modify the plant tolerance range to environmental factors by preconditioning and makes limits of plant tolerance to environmental factors flexible to a certain *** turn,as a result of tolerance range evolution,quantitative characteristics of hormesis(width and magnitude of hormetic zone)as well as the range of stimulatin

关键词： Hormetic dose-response Environmental limiting factor Plant stress Phenotypic plasticity Adaptive response

Energy Signaling in the Regulation of Gene Expression during Stress

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Molecular Plant 2010年第2期3卷 300-313页

作者： elena Baena-Gonzalez Instituto Gulbenkian de Ciencia Rua da Quinta Grande 6 2780-156 Oeiras Portugal

Maintenance of homeostasis is pivotal to all forms of life. In the case of plants, homeostasis is constantly threatened by the inability to escape environmental fluctuations, and therefore sensitive mechanisms must have evolved to allow rapid perception of environmental cues and concomitant modification of growth and developmental patterns for adaptation and survival. Re-establishment of homeostasis in response to environmental perturbations requires reprog- ramming of metabolism and gene expression to shunt energy sources from growth-related biosynthetic processes to defense, acclimation, and, ultimately, adaptation. Failure to mount an initial ＇emergency＇ response may result in nutrient deprivation and irreversible senescence and cell death. Early signaling events largely determine the capacity of plants to orchestrate a successful adaptive response. Early events, on the other hand, are likely to be shared by different conditions through the generation of similar signals and before more specific responses are elaborated. Recent studies lend credence to this hypothesis, underpinning the importance of a shared energy signal in the transcriptional response to various types of stress. Energy deficiency is associated with most environmental perturbations due to their direct or indirect deleterious impact on photosynthesis and/or respiration. Several systems are known to have evolved for monitoring the available resources and triggering metabolic, growth, and developmental decisions accordingly. In doing so, energy-sensing systems regulate gene expression at multiple levels to allow flexibility in the diversity and the kinetics of the stress response.

关键词： Abiotic/environmental stress metabolic regulation cell signaling gene expression post-transcriptionalcontrol transcriptional control and transcription factors.

Fukushima Fallout: Gauging the Change in Japanese Nuclear Energy Policy

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International Journal of Disaster Risk Science 2012年第2期3卷 69-83页

作者： elena Shadrina Graduate School of Governance Studies Meiji University Tokyo 101-0064 Japan

The Fukushima nuclear disaster is a special case: a major twin natural disaster(earthquake and tsunami) incited a large-scale technological disaster, which resulted in a serious nuclear accident. Because the various costs are so tremendous, this triple disaster has had a pervasive impact on all aspects of life in Japan. This article describes nuclear energy policy transformation in the aftermath of the Fukushim a disaster. The study draws on theoretical propositions of governance and disaster risk governance, and demonstrates that a vested interest perspective is important to understanding the results of Japan’s energy policy before Fukushima. Safety, democracy, and openness were the fundamental principles of Japan’s nuclear energy policy when the country decided to diversify its energy sources in the 1950 s. But these basic premises were undermined by the vested interests that controlled policy administration and implementation as the nuclear energy industry developed. Analysis of Japan’s recent nuclear energy policy transformation covers such dimensions as policy targets, policy issues such as safety, the fuel cycle, waste disposal, administrative structure, public awareness, and national and local policy considerations. The study identifies process deficiencies in Japan’s post-Fukushima nuclear energy policy transformation and evaluates possible ways to eliminate defects through administrative reorganization and independent safety oversight.

关键词： disaster eliminate administrative

Thrombin in peripheral nerves:friend or foe?

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Neural Regeneration Research 2021年第6期16卷 1223-1224页

作者： elena Pompili Cinzia Fabrizi Department of Anatomy HistologyForensic Medicine and OrthopedicsSapienza UniversityRomeItaly

Differently from the central nervous system(CNS),the peripheral nervous system(PNS)exhibits a high regenerative *** ability is related to the remarkable plasticity of Schwann cells(SCs)which after nerve injury convert to a repair-promoting phenotype to a large *** injury is accompanied by a rapid rise of thrombin levels(Bushi et al.,2016;Gera et al.,2016).Thrombin is the key effector protease of the coagulation cascade which elicits hormonelike actions by the activation of G-protein coupled receptors known as proteaseactivated receptors(PARs).Inflammation and coagulation are two complex and interconnected pathways whose mutual interactions have been only partially elucidated.

关键词： mutual injury convert

Reduction of CeO2 in composites with transition metal complex oxides under hydrogen containing atmosphere and its correlation with catalytic activity

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 249-261页

作者： elena Yu. KONYSHEVA School of Chemistry University of St Andrews KY169ST St Andrews Fife UK Department of Chemistry Xi'an Jiaotong-Liverpool University Suzhou 215123 China

Reduction behavior of pure and doped CeO2, the multi-phase ***2, ***0.2MnO3 . xCeO2, and ***2 composites, was studied under hydrogen containing atmosphere to address issues related to the improvement of electrochemical and catalytic performance of electrodes in fuel cells. The enhanced reduction of cerium oxide was observed initially at 800~C in all composites in spite of the presence of highly reducible transition metal cations that could lead to the increase in surface concentration of oxygen vacancies and generation of the electron enriched surface. Due to continuous reduction of cerium oxide in La0.6Sr0.4CoO3 ＂x- CeO2 and ***3 ＂xCeO2 （up to 10 h） composites the redox activity of the Ce4＋/Ce3＋ pair could be suppressed and additional measures are required for reversible spontaneous regeneration of Ce4＋. After 3 h exposure to H2-Ar at 800~C the reduction of cerium oxides and perovskite phases in La0.95Ni0.6Fe0.403 ＂xCeO2 com- posites was diminished. The extent of cerium oxide involvement in the reduction process varies with time, and depends on its initial deviation from oxygen stoichiometry （that results in the larger lattice parameter and the longer pathway for O2 transport through the fluorite lattice）, chemical origin of transition metal cations in the perovskite, and phase diversity in multi-phase composites.

关键词： reduction of cerium oxide composites perovskites catalyst under hydrogen containing atmosphere

Estrogens still represent an attractive therapeutic approach for Alzheimer’s disease

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Neural Regeneration Research 2022年第1期17卷 93-94页

作者： elena Tamagno Michela Guglielmotto Department of Neuroscience University of TorinoTorinoItaly(Tamagno EGuglielmotto M)Neuroscience Institute of Cavalieri Ottolenghi Foundation(NICO)University of TorinoTorinoItaly

Alzheimer’s disease(AD)is a progressive neurodegenerative condition that goes f rom mild cogni t ive impai rment in prodromal disease to severely disabling deficits in advanced *** risk for AD development,as well as progression and severity,clearly differ between men and women(Pike,2017).Epidemiological studies have shown that there is a significantly increased prevalence in the development of AD in women compared to men,which is usually explained by the longer lifespan of *** increased frequency may be due to the interplay between age and sex,in which genetic factors together with hormonal and metabolic patterns play a crucial ***,cognitive impairment has been confirmed to be greater in women than in men at the same stage of AD,likely due to reduced estrogen levels in postmenopausal women(Laws et al.,2016).

关键词： Alzheimer attractive therapeutic