238 research outputs found
The GALANTE photometric system
No full textThis paper describes the characterization of the GALANTE photometric system, a seven intermediate-and narrow-band filter system with a wavelength coverage from 3000 Å to 9000 Å. We describe the photometric system presenting the full sensitivity curve as a product of the filter sensitivity, CCD, telescope mirror, and atmospheric transmission curves, as well as some first-and second-order moments of this sensitivity function. The GALANTE photometric system is composed of four filters from the J-PLUS photometric system, a twelve broad-to-narrow filter system, and three exclusive filters, specifically designed to measure the physical parameters of stars such as effective temperature T, log (g), metallicity, colour excess E(4405-5495), and extinction type R. Two libraries, the Next Generation Spectral Library (NGSL) and the one presented in Maíz Apellániz & Weiler (2018), have been used to determine the transformation equations between the Sloan Digital Sky Survey (SDSS) ugriz photometry and the GALANTE photometric system. We will use this transformation to calibrate the zero-points of GALANTE images. To this end, a preliminary photometric calibration of GALANTE has been made based on two different griz libraries (SDSS DR12 and ATLAS All-Sky Stellar Reference Catalog, hereinafter RefCat2). A comparison between both zero-points is performed leading us to the choice of RefCat2 as the base catalogue for this calibration, and applied to a field in the Cyg OB2 association.© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.AL-G, EJA, and JMA acknowledge support from the Spanish Government Ministerio de Ciencia, Innovacion y Universidades though grants AYA2013-40 611-P and AYA2016-75 931-C2-1/2-P. A.L.-G and EJA also acknowledge support from the State Agency for Research of the Spanish MCIU through the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709).Peer Reviewe
Avram Galante his biography and his written works
No full textSosyal Bilimler Enstitüsü, Tarih Bölümü, Tarih Ana Bilim Dalı, Yakınçağ Tarihi Bilim DalıAvram Galante Bodrumlu: Eğitimci, Gazeteci, Pedagog, Filolog ve Milletvekili? Ancak özellikle Tarihçi? 1873 yılında ?Tarihin Babası? olarak bilinen Herodot gibi Bodrum'da doğmuştur. Galante'nin araştırmalarının ağırlık noktasını ?Türkiye Yahudileri Tarihi? oluşturmuştur. Bu konuda yerli - yabancı birçok kişinin ilk başvuru kaynağı olmuştur. Yazar, eserlerini metodik ve titiz bir çalışma sonucu yazmıştır. Türkçeden başka İngilizce, Almanca, Fransızca, İbranice, Arapça, Farsça, İspanyolca, Rumca ve Ermenice bilen Galante, belgeleri orijinallerinden okuyarak gerçek anlamlarını kavrayabilmiştir. Kendisini tamamen ilmi çalışmalara veren Galante hiç evlenmemiştir. Niğde milletvekilliğinden ayrıldığı 1946 yılından, vefat ettiği yıl olan 1961 yılına kadar Kınalı ada'daki evinde, tek başına, sessiz ve temiz bir yaşam sürmüştür. Son nefesine kadar araştırmalarına ve yazılarına devam etmiştir. Prof. Dr. Avram Galante Bodrumlunun biyografisi ve eserleri konusunda şimdiye kadar ciddi bir ilmi çalışmanın yapılmamış olması bizi bu konu üzerinde çalışmaya yöneltmiştir.Anahtar sözcükler: Abraham Galante, Niğde Milletvekilleri, Türkiye Yahudileri.Avram (Abraham) Galante: Was an educator, a pedagogue , a philogue, a journalist, and a deputy. But especially he was a historian. Avram Galante was born in Bodrum in 1873 like Heredot who was known ?father of history?. Galante?s researches?s about at ?Turkish Jewish?s History?. This researches was his bibliography for national and international researchers every time. Author Galante was hard to please about his written works. He wrote his written works with amethodology. Galante was know a lot of language; Turkish, English, German, French, The Hebrew Language, Arabic, İranian, Spanish, Grek Language and Armenian language. İn this connection, he read the documents from origin. And he grasped the original documents?s real meanings. Or he had knowledge of their semantics. He never married because, he interested in scientific subjects. He seperated from deputy of Niğde in 1946. He died in 1961. He lived in his hause at Kınalıada until 1961. His life was alone, peaceful and honourable, in his island. He made researches and he wrote about his researches all of his life. Concerning Professor Dr. Avram Galante thre weren?t any investigation about his biography and his written works . For this reason , we directed to work at this area.Keywords: Abraham Galante, deputy of Niğde, Turkish Jewish
Integrated geochemical and morphological data provide insights into the genesis of ferromanganese nodules
No full textFerromanganese nodules grow by precipitation of metals from seawater and/or sediment pore water. The formation of different genetic types depends on the composition and redox conditions of the water and upper sediment layers, water depth, and primary productivity in surface waters. Many characteristics of nodules have been used to investigate their genesis. In this paper, we compare nodules from different environments using Computed Tomography, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy, and Micro X-ray Fluorescence data to better understand how geochemical differences are linked to different morphological features. We use representative samples of purely hydrogenetic nodules and mixed-type nodules with various proportions of hydrogenetic and diagenetic growth laminae. Our results show a micrometric alternation between high-absorbance massive Mn-enriched (Mn/Fe up to 40) laminae and low-absorbance dendritic Mn-depleted (Mn/Fe about 1) laminae in mixed-type nodules, suggesting the rhythmic alternation of hydrogenetic oxic conditions and suboxic diagenetic input. This micro-rhythmic alternation is absent in purely hydrogenetic nodules, which are homogenous both chemically and morphologically. A conceptual model is proposed to account for these geochemical and morphological differences in terms of the vertical migration of the oxic-suboxic front relative to the base of the nodules
Le système de l'iconographie galante
No full textAlain Guillerm : The system of 18th-century love engravings.
An attempt to decipher 18th-century French engravings which enter into the vague category of «galant », although this term is not easy to define. In order to discover their symbolic system, this article considers, by way of comparison, a series of erotic engravings at the Bibliothèque nationale, in which the meaning of the symbols is clearly indicated. These examples, and the relationship between different engravings, enable the author to throw light on certain allusions and signs. He emphasizes the impossibility of providing a rigid system of interpretation, and insists that the symbols are above all light-hearted ; they do not express the subconscious, but form a deliberate system of enunciation, which is on occasion subversive.Guillerm Alain. Le système de l'iconographie galante. In: Dix-huitième Siècle, n°12, 1980. Représentations de la vie sexuelle. pp. 177-194
Supplementary file for "Primitive magnetotaxis in 1.88 Ga gigantic magnetofossils"
No full textGigantic magnetofossils' occurrence is very restricted along the geological records. Distinguishing them from ordinary nanoscopic magnetotactic organisms, the biosynthesized iron oxides these organisms produce are micrometric, and the biological function of synthesizing such large grains is still unknown. We approach the problem by micromagnetic modeling synthetic chains of gigantic magnetofossils built based on 3D-Ptychographic data of Precambrian (1.88 Ga) fossils. In this dataset, we include the meshes used in our simulations (.pat files), Python scripts, MERRILL scripts, and outputs achieved from the simulations (.out files).Ualisson Donardelli Bellon, Wyn Williams, Ricardo Ivan Ferreira Trindade, Lara Maldanis, & Douglas Galante. (2023). Supplementary file for "Primitive magnetotaxis in 1.88 Ga gigantic magnetofossils" [Data set]. Zenodo. https://doi.org/10.5281/zenodo.839067
Astrophysical and Astrobiological effects of Gamma-Ray Bursts
No full textO presente trabalho tem o objetivo principal de compreender os possíveis efeitos da radiação energética de um evento de Gamma-Ray Burst (GRB) sobre o meio interestelar no entorno de seu local de geração e em planetas possivelmente iluminados. Gamma-Ray Bursts foram detectados pela primeira vez nos anos 60 e rapidamente atraíram a atenção da comunidade astrofísica, uma vez que as energias emitidas apenas em poderiam alcançar 1054erg, o equivalente a massa de repouso do Sol. Não se conhecia nenhum mecanismo tão eficiente para extrair energia gravitacional para produzir tal evento. Mais tarde, a possibilidade da emissão ser colimada abaixou a energia em para 5x1050erg, mas o mecanismo central de geração ainda não foi completamente desvendado, havendo muito espaço para alternativas exóticas. Estudamos os efeitos de um GRB sobre o meio interestelar, em uma tentativa de distinguir os remanescentes do GRB do gerado por múltiplas supernovas. Usamos argumentos energéticos e sobre a possibilidade de alterações químicas e isotópicas devido a reações fotonucleares. Também trabalhamos com as implicações biológicas da iluminação de planetas por um GRB, concluindo que os efeitos de tais eventos podem afetar seriamente a biosfera de um planeta mesmo a distâncias de ~10kpc.The present work has the main goal of understanding the possible effects of the hard gamma radiation produced during a Gamma-Ray Burst (GRB) event both on the interstellar medium surrounding the source of the burst and on planets possibly illuminated. Gamma-Ray Bursts were first detected on the 60s and quickly have attracted the attention of the astrophysical community, since the energies emitted just in could reach 1054erg, the rest mass of the Sun. No mechanism was known to be so efficient in extracting gravitational energy to produce such emission. Later on, the possibility of the emission being collimated has lowered the energy of the to 5x1051erg, but the central engine has not yet been completely understood, and there is still ample room for exotic alternatives. We have studied the effects of GRB on the ISM, in an attempt to distinguish the candidates of GRB remnants from those generated by multiple supernovae. We have used both energetic arguments and the possibility of chemical alterations due to photonuclear reactions. We have also worked on the biological implications of the illumination of planets by a GRB, concluding that the effects of such event could seriously harm the biosphere of a planet even at distances of ~10kpc
Resistance to environmental stresses of co-cultures among Exophiala sp. and isolated yeasts of the genus Saccharomyces for application in space exploration
No full textO processo de exploração espacial encontra-se cada vez mais próximo da realidade com as novas missões para Lua e Marte. Com o intuito de facilitar a sobrevivência humana em Marte, o desenvolvimento de tecnologia se torna essencial neste contexto. As leveduras já são amplamente utilizadas na indústria de biotecnologia na produção de alimentos, bebidas, fármacos, combustível entre outros, sendo assim podendo ser utilizados como ferramenta biotecnológica na exploração espacial. O presente projeto teve como objetivo submeter as leveduras às condições ambientais de Marte, utilizando a co-cultura de leveduras do gênero Saccharomyces com uma levedura poli extremofila, Exophiala sp, já que essa poderia fornecer algum tipo de proteção extra para as leveduras estudadas, afetando suas respostas aos diversos tipos de estresses. As leveduras foram submetidas aos diferentes tipos de condições extremas análogas à Marte, como alta incidência de radiação UV (UV-C, UV-B e UV-A), dessecação, anaerobiose, baixa pressão atmosférica e salinidade. Esses eucariotos unicelulares foram cultivados com e sem co-cultura e as respostas foram medidas através de contagem de UFC (unidade formadora de colônia), com a finalidade de avaliar tanto a capacidade desses microrganismos de resistirem e/ou crescerem nas condições hostis. A maioria das leveduras foram resistentes a todas as condições experimentais, tendo como destaque a levedura cervejeira HA-18, mesmo na ausência da co-cultura. Os dados experimentais demonstraram que as leveduras foram capazes de resistir às condições extremas análogas à Marte, na maioria superiores a da bactéria Deinococcus radiodurans, organismo modelo em astrobiologia. Desta maneira, as leveduras também poderiam ser utilizadas como organismos-modelo de grande importância para a exploração espacial e para possível aplicação para colonização planetária.The space exploration process is getting closer to reality with the new missions for the Moon and Mars. In order to facilitate human survival on Mars, the development of technology becomes essential in this context. Yeasts are already widely used in the biotechnology industry in the production of food, beverages, drugs, fuel, among others, and thus can be used as a biotechnological tool in space exploration. This project aimed to submit the yeasts to environmental conditions on Mars, using the co-culture of yeasts of the genus Saccharomyces with a poly extremophile yeast, Exophiala sp, as this could provide some kind of extra protection for the studied yeasts, affecting their responses to different types of stresses. The yeasts were subjected to different types of extreme conditions analogous to Mars, such as high incidence of UV radiation (UV-C, UV-B and UV-A), desiccation, anaerobiosis, low atmospheric pressure and salinity. These unicellular eukaryotes were cultivated with and without co-culture and the responses were measured by counting CFU (colony forming unit), in order to assess both the ability of these microorganisms to resist and/or grow under hostile conditions. Most yeasts were resistant to all experimental conditions, with the highlight being the brewer\'s yeast HA-18, even in the absence of co-culture. Experimental data showed that the yeasts were able to withstand extreme conditions analogous to Mars, most of them superior to those of the bacterium Deinococcus radiodurans, a model organism in astrobiology. In this way, yeasts could also be used as model organisms of great importance for space exploration and a possible application for planetary colonization
Simulation of the biological direct and indirect damage from Solar Winds protons in D.radiodurans and E.coli using the Monte Carlo simulation toolkit Geant4-DNA.
No full textO presente trabalho apresenta como novidade o uso do kit de ferramentas de simulação Monte Carlo Geant4-DNA para estudo dos danos biológicos diretos ao DNA e indiretos químicos medindo a formação de ROS pela radiólise da água, ambos causados por prótons do Vento Solar, nas bactérias D.radiodurans e E.coli. O Vento Solar foi simulado por dois tipos de fontes, uma monoenergética e outra com espectro e energia por Lei de Potência, baseadas em dados reais de taxas de fluência e energia dos prótons medida pelo satélite ACE-Explorer no mês de Agosto de 2018. Os objetivos deste estudo para o dano direto são: inicialmente calcular com o Geant4-DNA números médios de quebras de DNA por próton, Tamanho médio e Número de clusters de dano formados por próton, e Dose Absorvida por próton. Depois a partir deles os números médios de quebras de fitas de DNA e números de clusters por Gy e por Gy por Mbp, e com os dados do satélite ACE-Explorer para as taxas de fluência dos prótons a Dose Absorvida média por dia. Por fim uni-los todos com os valores experimentais de Doses Letais de sobrevivência das bactérias e estimar os tempos de exposição necessários ao Vento Solar para se atingir as doses e números totais de SB e números gerados. Para o dano indireto os objetivos são: calcular com o Geant4-DNA números de moléculas formadas e fator radioquímico G por próton e a Dose Absorvida média na fase química. Depois, com estes valores, calcular o número máximo de moléculas formadas por Gy e unindo com valores de Doses Letais estimar o número total de moléculas formadas; e estimar graficamente os tempos de pico, as meias-vidas e distâncias médias de difusão das espécies químicas de interesse.The present work brings as novelty the use of the Monte Carlo simulation toolkit Geant4- DNA for the study of direct biological damage to DNA and chemical indirect damage by measuring the formation of ROS by the radiolysis of water, both caused by protons from the Solar Wind, in the bacteria D.radiodurans and E.coli. The Solar Wind was simulated by two types of sources, one monoenergetic and the other with energy distribution spectrum by a Power Law, based on real data of fluence rates and proton energies measured by the ACEExplorer satellite in August 2018. Objectives of this study for direct damage are: initially calculate with Geant4-DNA average numbers of DNA breaks per proton, Average Size and Number of damage clusters formed per proton, and Absorbed Dose per proton. After that the average numbers of DNA strand breaks and numbers of clusters per Gy and per Gy per Mbp, and with the ACE-Explorer satellite data for the proton fluence rates the average Absorbed Dose per day. Finally, unite them all with the experimental values for Lethal Doses taken from experimental data for survival of bacteria and estimate the necessary exposure times to Solar Wind to reach the doses, and total numbers of SB and numbers of clusters generated. For the indirect damage the objectives are: calculate with Geant4-DNA the mean numbers of molecules formed and radio chemical factor G per proton and the mean Absorbed Dose per proton in the chemical phase. Then with these values calculate the maximum number of molecules formed by Gy and joining them with the Lethal Doses to estimate the total number of molecules formed; and at last graphically estimate the peak times, half-lives and mean diffusion distances of the chemical species of interest
Natural radioactive environments as a source of local disequilibrium in planetary and prebiotic scenarios
No full textCertos ambientes subterrâneos da Terra possuem acumulados, naturalmente, compostos de radionuclídeos de longa vida, como 238U, 232Th 40K, próximo à presença de água líquida. O mesmo é esperado que aconteça em corpos planetários, no Sistema Solar, que possua quantidades apreciáveis de água. Nestes ambientes radioativos naturais, a radiólise da água produz espécies químicas e desequilíbrios químicos importantes para a vida. Apesar da proposta do decaimento radioativo como fonte alternativa de energia para sistemas vivos existir há mais de trinta anos, isto se mostrou realmente concreto após descoberta de um ecossistema peculiar cuja sobrevivência é dependente de espécies químicas produzidas por radiólise aquosa. Neste trabalho, avaliamos e quantificamos os desequilíbrios químicos gerados localmente pela radiólise aquosa e a possível contribuição destes para a emergência da vida, tendo como referência os estudos em ambientes de fontes hidrotermais alcalinas, consideradas promissores ambientes para esse evento. Também foram avaliados seus efeitos na habitabilidade de possíveis ambientes análogos na lua gelada Europa. Procuramos quantificar a diversidade química formada nessas condições e a associar aos desequilíbrios parâmetros termodinâmicos. As estimativas realizadas para ambientes radioativos na Terra primitiva apontaram para a similaridade entre o desequilíbrio causado por radiólise aquosa e o encontrado em fontes hidrotermais alcalinas. Confirmando e detalhando a análise preliminar que motivou o trabalho. Não obstante, considerando Europa, chegamos a valores de densidade de células do extremófilo Candidatus Desulforudis audaxviator que sobreviveriam em um conjunto de candidatos a análogos geológicos de possível ambiente radioativo na lua gelada. A partir deste estudo pudemos analisar o potencial para a emergência da vida e de protometabolismos nestes ambientes radioativos naturais na Terra primitiva, bem como levantar parâmetros mensuráveis para futuras missões espaciais que buscam vida ou habitabilidade em Europa.Certain subterranean environments of the Earth has naturally accumulated compounds of longlived radionuclides, such as 238U, 232Th 40K, near the presence of liquid water. The same is estimated in wet planetary bodies in the Solar System. In these natural radioactive environments, water radiolysis produces chemical species and chemical disequilibria, which are important for life. Although the proposal of radioactive decay as an alternative source of energy for deep biospheres has existed for more than thirty years, this proved to be really feasible after the discovery of a peculiar ecosystem whose survivor is dependent on chemical species produced by water radiolysis. In this work, we evaluate and quantify the chemical disequilibria generated locally by water radiolysis and the possible contribution of these to the emergence of life, having as reference the studies alkaline hydrothermal vents, which is considered highly promising environment for this event. It is also evaluated their effects on the habitability of possible analogous environments on the Jupiter icy moon Europa. It was aimed to quantify the chemical diversity formed under these conditions and to calculate disequilibria using thermodynamic parameters. The estimates made for natural radioactive environments in early Earth pointed to the similarity between the disequilibrium caused by water radiolysis and those found in alkaline hydrothermal vents. What confirms and details the preliminary analysis that motivated this work. In addition, it was calculated values for cell density of the Candidatus Desulforudis audaxviator extremophile, that would survive in Europa comparable to the in situ analysis of some terrestrial radioactive environments, using a set of possible scenarios for possible local natural radioactive environments. From this study, we were able to analyze the potential for the emergence of life and protometabolisms in these natural radioactive environments in early Earth, as well as to provide measurable parameters for future space missions that seek for life or habitability in Europa
Environmental simulations and spectroscopic in situ characterization of potential molecular biosignatures for application in space missions
No full textA Astrobiologia é uma área de pesquisa crescente no Brasil, na qual se estuda o fenômeno da vida no Universo. Um de seus subtemas estuda as bioassinaturas: substâncias que evidenciam da presença de vida, passada ou presente. Foram investigadas em laboratório a detectabilidade de biomoléculas, que são potenciais bioassinaturas moleculares, e a fotoestabilidade de suas assinaturas espectroscópicas em ambientes extraterrestres simulados. Os experimentos foram baseados em irradiações no ultravioleta, que é a principal faixa da radiação solar responsável pela evolução e degradação de moléculas orgânicas em ambientes espaciais. Um maior foco foi dado aos pigmentos biológicos β-caroteno e clorofila a, os quais foram irradiados puros e/ou misturados a diferentes substratos inorgânicos, mimetizando superfícies de planetas rochosos, satélites e asteroides. Foram utilizadas as instalações do Laboratório Nacional de Luz Síncrotron (LNLS), em especial a linha de luz TGM, na faixa do UV, VUV e EUV, e também lâmpadas de baixa pressão que emitem na faixa do UVC. Na Câmara de Simulação Espacial e Planetária (AstroCam), do Núcleo de Pesquisa em Astrobiologia da USP (NAP/Astrobio), diversos parâmetros ambientais foram controlados para simular as condições da superfície de Marte. E balões de alta-altitude foram utilizados para testar a resposta de biomoléculas na estratosfera, cujas condições são similares às da superfície marciana, além de validar experimentos que podem ser enviados em missões espaciais. As mudanças nas respostas espectroscópicas das biomoléculas foram medidas por absorbância no UV-Vis e no IR e por espalhamento Raman, algumas in situ e em tempo real e outras ex situ. As técnicas provaram ser adequadas para esses estudos pois forneceram informações sobre as fotoestabilidades das respostas espectroscópicas das biomoléculas, permitindo testar seus potenciais como bioassinaturas em diferentes superfícies do Sistema Solar. Os resultados também podem contribuir para missões espaciais, dando suporte ao desenvolvimento e otimização de técnicas e procedimentos para estudar os efeitos da exposição de biomoléculas a ambientes espaciais reais – em missões de pequeno porte e baixo custo, como CubeSats –, e até mesmo para a detecção de bioassinaturas em superfícies planetárias extraterrestres.Astrobiology is a growing research area Brazil, which studies the phenomenon of life in the Universe. One of its sub-themes studies biosignatures: substances which evidence the presence of life, past or present. The detectability of biomolecules, which are potential molecular biosignatures, and the photostability of their spectroscopic signatures in simulated extraterrestrial environments were investigated in laboratory. The experiments were based on irradiations in the ultraviolet, which is the main range of solar radiation responsible for the evolution and degradation of organic molecules in space environments. The research was focused in the biological pigments β-carotene and chlorophyll a, which were irradiated in both pure form and/or mixed with different inorganic substrates, mimicking the surfaces of rocky planets, satellites and asteroids. The facilities of the Brazilian Synchrotron Light Laboratory (LNLS) were used, especially the TGM beamline in the UV, VUV and EUV range, as well as low pressure lamps emitting in the UVC range. In the Space and Planetary Simulation Chamber (AstroCam) of the Astrobiology Research Unit of USP, several environmental parameters were controlled to simulate the surface conditions of Mars. And high-altitude balloons were used to test the response of biomolecules in the stratosphere, where the conditions are similar to those of the Martian surface, in addition to validate experiments which can be sent in space missions. Changes in the biomolecules spectroscopic responses were measured by UV-Vis and IR absorbance and by Raman scattering, either in situ and in real time or ex situ. The techniques proved to be adequate for these studies, since they provided information on the photostability of the biomolecules spectroscopic responses, allowing the testing of their potential as biosignatures on different surfaces of the Solar System. The results can also contribute to space missions, supporting the development and optimization of techniques and procedures, both for the exposure of biomolecules to real space environments – in small and low-cost missions, such as CubeSats –, as well as for the actual detection of biosignatures on extraterrestrial planetary surfaces
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