Photospheric properties and fundamental parameters of M dwarfs

M dwarfs are an important source of information when studying and probing the lower end of the Hertzsprung-Russell (HR) diagram, down to the hydrogen-burning limit. Being the most numerous and oldest stars in the galaxy, they carry fundamental information on its chemical history. The presence of molecules in their atmospheres, along with various condensed species, complicates our understanding of their physical properties and thus makes the determination of their fundamental stellar parameters more challenging and difficult. The aim of this study is to perform a detailed spectroscopic analysis of the high-resolution H-band spectra of M dwarfs in order to determine their fundamental stellar parameters and to validate atmospheric models. The present study will also help us to understand various processes, including dust formation and depletion of metals onto dust grains in M dwarf atmospheres. The high spectral resolution also provides a unique opportunity to constrain other chemical and physical processes that occur in a cool atmosphere The high-resolution APOGEE spectra of M dwarfs, covering the entire H-band, provide a unique opportunity to measure their fundamental parameters. We have performed a detailed spectral synthesis by comparing these high-resolution H-band spectra to that of the most recent BT-settl model and have obtained fundamental parameters such as effective temperature, surface gravity, and metallicity (Teff, log g and [Fe/H]) respectively.Comment: 15 pages, 10 figures, accepted for publication in A&

The ionizing sources of luminous compact HII regions in the RCW106 and RCW122 clouds

Given the rarity of young O star candidates, compact HII regions embedded in dense molecular cores continue to serve as potential sites to peer into the details of high-mass star formation. To uncover the ionizing sources of the most luminous and compact HII regions embedded in the RCW106 and RCW122 giant molecular clouds, known to be relatively nearby (2-4 kpc) and isolated, thus providing an opportunity to examine spatial scales of a few hundred to a thousand AU in size. High spatial resolution (0.3"), mid-infrared spectra (R=350), including the fine structure lines [ArIII] and [NeII], were obtained for four luminous compact HII regions, embedded inside the dense cores within the RCW106 and RCW122 molecular cloud complexes. At this resolution, these targets reveal point-like sources surrounded by nebulosity of different morphologies, uncovering details at spatial dimensions of <1000AU. The point-like sources display [ArIII] and [NeII] lines - the ratios of which are used to estimate the temperature of the embedded sources. The derived temperatures are indicative of mid-late O type objects for all the sources with [ArIII] emission. Previously known characteristics of these targets from the literature, including evidence of disk or accretion suggest that the identified sources may grow more to become early-type O stars by the end of the star formation process

The pro-resolving lipid mediator Maresin 1 ameliorates pain responses and neuroinflammation in the spared nerve injury-induced neuropathic pain: A study in male and female mice

Specialized pro-resolving mediators (SPMs) have recently emerged as promising therapeutic approaches for neuropathic pain (NP). We evaluated the effects of oral treatment with the SPM Maresin 1 (MaR1) on behavioral pain responses and spinal neuroinflammation in male and female C57BL/6J mice with spared nerve injury (SNI)-induced NP. MaR1, or vehicle, was administered once daily, on post-surgical days 3 to 5, by voluntary oral intake. Sensory-discriminative and affective-motivational components of pain were evaluated with von Frey and place escape/avoidance paradigm (PEAP) tests, respectively. Spinal microglial and astrocytic activation were assessed by immunofluorescence, and the spinal concentration of cytokines IL-1 & beta;, IL-6, IL-10, and macrophage colony-stimulating factor (M-CSF) were evaluated by multiplex immunoassay. MaR1 treatment reduced SNI-induced mechanical hypersensitivity on days 7 and 11 in both male and female mice, and appeared to ameliorate the affective component of pain in males on day 11. No definitive conclusions could be drawn about the impact of MaR1 on the affective-motivational aspects of pain in female mice, since repeated suprathreshold mechanical stimulation of the affected paw in the dark compartment did not increase the preference of vehicle-treated SNI females for the light side, during the PEAP test session (a fundamental assumption for PAEP's validity). MaR1 treatment also reduced ipsilateral spinal microglial and astrocytic activation in both sexes and marginally increased M-CSF in males, while not affecting cytokines IL-1 & beta;, IL-6 and IL-10 in either sex. In summary, our study has shown that oral treatment with MaR1 (i) produces antinociception even in an already installed peripheral NP mouse model, and (ii) this antinociception may extend for several days beyond the treatment time-frame. These therapeutic effects are associated with attenuated microglial and astrocytic activation in both sexes, and possibly involve modulation of M-CSF action in males.& nbsp;This work was supported by University of Porto/Faculty of Medicine (https://sigarra.up.pt/fmup) and ESF - European Social Fund (https://ec. europa.eu/esf/home.jsp), through NORTE2020 - North Portugal Regional Operational Programme [NORTE-08-5369-FSE-000011-Doctoral Programmes - LTS' PhD fellowship], and by Fundacao Grunenthal Portugal (https://www. fundacaogrunenthal.pt), Bolsa Jovens Investigadores em Dor 2018 - LTS). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Caracterização de Latossolo Amarelo no município de Parintins: Estado do Amazonas: alguns atributos físicos, químicos e hídricos.

O presente estudo teve por objetivo caracterizar um Latossolo predominante na paisagem da Serra de Parintins com o intuito de contribuir para uma melhor utilização do solo pelos produtores, considerando como padrão solo sob floresta e áreas cultivadas

Mkp3 is a negative feedback modulator of Fgf8 signaling in the mammalian isthmic organizer

The pivotal mechanisms that govern the correct patterning and regionalization of the distinct areas of the mammalian CNS are driven by key molecules that emanate from the so-called secondary organizers at neural plate and tube stages. FGF8 is the candidate morphogenetic molecule to pattern the mesencephalon and rhombencephalon in the isthmic organizer (IsO). Recognizable relevance has been given to the intracellular pathways by which Fgf8 is regulated and modulated. In chick limb bud development, a dual mitogen-activated protein kinase phosphatase-3 (Mkp3) plays a role as a negative feedback modulator of Fgf8 signaling. We have investigated the role of Mkp3 and its functional relationship with the Fgf8 signaling pathway in the mouse IsO using gene transfer microelectroporation assays and protein-soaked bead experiments. Here, we demonstrate that MKP3 has a negative feedback action on the MAPK/ERK-mediated FGF8 pathway in the mouse neuroepithelium. (C) 2004 Elsevier Inc. All rights reserved.info:eu-repo/semantics/publishedVersio

Innovative solar concentration systems and its potential application in Angola

Energy demands have been increasing worldwide, endangering the future supply–demand energy balance. To provide a sustainable solution for future generations and to comply with the international goal to achieve Carbon Neutrality by 2050, renewable energies have been at the top of the international discussions, actively contributing to the energy transition and climatic policies. To achieve the international goal, Angola proposed a long-term strategy that promotes a fair and sustainable development of the national territory by means of improving the electric sector. Among all the renewable resources, solar energy is found to be the most promising solution since it has the second major renewable energy potential in Angola. However, the main problem related to solar energy is the efficiency of the solar systems and the electrical and thermal energy storage. As part of the solution, Concentration Solar Power (CSP) can make a sounder contribution to the transformation of the Angolan energy sector since it enables a significant increase in energy intensity through the concentration of solar energy. Moreover, the large applicability of this technology can contribute to the development of the rural regions which still struggle for energy equity. By considering the potential of CSP, this work presents the status of the Angolan energy sector, and focus is provided on the solar potential of the country. The advantages of the CSP technologies with emphasis on the parabolic dish systems are presented, and the contribution and innovative solutions for the enhancement of thermal efficiency are presented.This research was funded by FCT-Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020 (ALGORITMI Center) and Project Scope UIDB/00319/2020 (METRICS Center)