10 research outputs found

    Inoculation of the Leishmania infantum HSP70-II null mutant induces long-term protection against L. amazonensis infection in BALB/c mice

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    Leishmania amazonensis parasites are etiological agents of cutaneous leishmaniasis in the New World. BALB/c mice are highly susceptible to L. amazonensis challenge due to their inability to mount parasite-dependent IFN-γ-mediated responses. Here, we analyzed the capacity of a single administration of the LiΔHSP70-II genetically-modified attenuated L. infantum line in preventing cutaneous leishmaniasis in mice challenged with L. amazonensis virulent parasites. In previous studies, this live attenuated vaccine has demonstrated to induce long-protection against murine leishmaniasis due to Old World Leishmania species. Vaccinated mice showed a reduction in the disease evolution due to L. amazonensis challenge, namely reduction in cutaneous lesions and parasite burdens. In contrast to control animals, after the challenge, protected mice showed anti-Leishmania IgG2a circulating antibodies accompanied to the induction of Leishmania-driven specific IFN-γ systemic response. An analysis performed in the lymph node draining the site of infection revealed an increase of the parasite-specific IFN-ϒ production by CD4+ and CD8+ T cells and a decrease in the secretion of IL-10 against leishmanial antigens. Since the immunity caused by the inoculation of this live vaccine generates protection against different forms of murine leishmaniasis, we postulate LiΔHSP70-II as a candidate for the development of human vaccines.This research was funded by grants from Ministerio de Ciencia e Innovación FISPI11/00095 and FISPI14/00366 (FEDER FUNDING) to M.S. and RYC-2016-19463 and RTI2018-343 to S.I. J.M.R. and M.S. are funded by the Fondo de Investigaciones Sanitarias (ISCIII-RETICRD16/0027/008-FEDER). E.H.G. is supported by a FPI grant from the Spanish Ministerio de Ciencia e Innovación. Institutional grants from the Fundación Ramón Areces and Banco de Santander to the CBMSO are also acknowledged. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe

    Temporal evolution of the Evershed flow in sunspots. I. Observational characterization of Evershed clouds

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    [Abridged] The magnetic and kinematic properties of the photospheric Evershed flow are relatively well known, but we are still far from a complete understanding of its nature. The evolution of the flow with time, which is mainly due to appearance of velocity packets called Evershed clouds (ECs), may provide information to further constrain its origin. Here we undertake a detailed analysis of the evolution of the Evershed flow by studying the properties of ECs. In this first paper we determine the sizes, proper motions, location in the penumbra, and frequency of appearance of ECs, as well as their typical Doppler velocities, linear and circular polarization signals, Stokes V area asymmetries, and continuum intensities. High-cadence, high-resolution, full vector spectropolarimetric measurements in visible and infrared lines are used to derive these parameters. We find that ECs appear in the mid penumbra and propage outward along filaments with large linear polarization signals and enhanced Evershed flows. The frequency of appearance of ECs varies between 15 and 40 minutes in different filaments. ECs exhibit the largest Doppler velocities and linear-to-circular polarization ratios of the whole penumbra. In addition, lines formed deeper in the atmosphere show larger Doppler velocities, much in the same way as the ''quiescent'' Evershed flow. According to our observations, ECs can be classified in two groups: type I ECs, which vanish in the outer penumbra, and type II ECs, which cross the outer penumbral boundary and enter the sunspot moat. Most of the observed ECs belong to type I. On average, type II ECs can be detected as velocity structures outside of the spot for only about 14 min. Their proper motions in the moat are significantly reduced with respect to the ones they had in the penumbra.Comment: Accepted for publication in A&

    Sunspots: from small-scale inhomogeneities towards a global theory

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    The penumbra of a sunspot is a fascinating phenomenon featuring complex velocity and magnetic fields. It challenges both our understanding of radiative magneto-convection and our means to measure and derive the actual geometry of the magnetic and velocity fields. In this contribution we attempt to summarize the present state-of-the-art from an observational and a theoretical perspective.Comment: Accepted for publication in Space Science Review

    Point View in Bird and Flower Painting

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    在中国传统绘画中,点景是极其重要的一种表达方式。石涛所研究的绘画问题中,情感、理性、力量都是不可缺少的,如何恰当地运用这三者,却有可能导致完全不同的创作结果。而点景正是这三者的集合点,不仅要用心灵去感受自然对象的内在精神,不能因为对象的限制而使感受层次也受到限制,把眼睛之受升华为心理之受。在绘画作品中合理地运用点景能使画家的情感与物象更加融合,画家自身的主观感受在画面上得到充分的体现,以一种小的特殊表现符号流露出画家作品里表达的象征倾向和审美概念,对画面的构图及意境有着画龙点睛的作用。本文以花鸟画点景为研究对象,重点介绍了点景的表现与意义;进一步阐述了点景在传统花鸟画构成中的作用,着重论述其在...The “point view” is extremely important as a means of expression in the traditional Chinese painting. Emotion, rationality and power are essential in the Shi Tao studied painting, and how to properly use them may lead to the creation of a completely different result. For the reason that “point view” is a collection of these three points, shouldn’t we only use the soul to feel the inner spirit of n...学位:文学硕士院系专业:艺术教育学院美术系_美术学学号:1862007115166

    Antigen Processing and Presentation

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