782 research outputs found
Extensive local adaptation within the chemosensory system following Drosophila melanogaster's global expansion.
How organisms adapt to new environments is of fundamental biological interest, but poorly understood at the genetic level. Chemosensory systems provide attractive models to address this problem, because they lie between external environmental signals and internal physiological responses. To investigate how selection has shaped the well-characterized chemosensory system of Drosophila melanogaster, we have analysed genome-wide data from five diverse populations. By couching population genomic analyses of chemosensory protein families within parallel analyses of other large families, we demonstrate that chemosensory proteins are not outliers for adaptive divergence between species. However, chemosensory families often display the strongest genome-wide signals of recent selection within D. melanogaster. We show that recent adaptation has operated almost exclusively on standing variation, and that patterns of adaptive mutations predict diverse effects on protein function. Finally, we provide evidence that chemosensory proteins have experienced relaxed constraint, and argue that this has been important for their rapid adaptation over short timescales
Evolução do processo de capacitação dos servidores da Universidade Federal Do Maranhão (UFMA) / Evolution of the training process of the Federal University Of Maranhão (UFMA)
Capacitar funcionários, de quaisquer iniciativas é dever de toda boa empresa que almeja um desempenho eficiente de sua equipe. No âmbito federal, a capacitação é tratada já na Lei 8.112/1990, artigo 87. Na UFMA esta atividade vem sendo desenvolvida desde então, mas ganhou mais relevância a partir do início do século XX, em especial, em 2012, depois da Implementação do Sistema Integrado de Gestão (SIG), por meio da ferramenta Sistema de Recursos Humanos (SIGRH), que permitiu, além da informatização dos dados dos funcionários, uma maior divulgação dos cursos, facilitando, inclusive, a inscrição dos servidores. O objetivo deste trabalho, centrado nesta questão, é mostrar a evolução desse trabalho de capacitação, em especial, a partir da segunda metade de 2019, quando foi implementada a capacitação por meio da plataforma Moodle, disponibilizada pela Diretoria Interdisciplinar de Tecnologias na Educação (DINTE), tomando como base para análise, cursos de habilidades linguísticas. O trabalho adota abordagens descritivo-analítica e o aparato teórico que o norteia está centrado, sobretudo, na legislação vigente e nas Portarias veiculadas pela Universidade Federal do Maranhão.
Cercosporin production by Cercospora coffeicola isolates: spectrophotometry and HPLC quantification and image analysis
Cercosporin has excellent properties of photosensitization that have been widely used in organophotocatalyst and photodynamic
therapy as well as an antimicrobial agent. Therefore, there is a need to quantify it accurately with accessible methods.
A comparative analysis of cercosporin quantification obtained by spectrophotometry (SPEC) and high-performance liquid
chromatography (HPLC) was performed for nineteen Cercospora coffeicola isolates from different coffee-producing municipalities
in Brazil. Image analysis of cercosporin crystals was performed in isolates with either high or low production of
the toxin. Our results show that SPEC and HPLC are equally valid for the cercosporin evaluation of C. coffeicola cultures
grown in vitro. The isolates with high cercosporin production had a higher crystal number and size when compared to the
one with low cercosporin productioninfo:eu-repo/semantics/publishedVersio
Generalized contact process on random environments
Spreading from a seed is studied by Monte Carlo simulation on a square
lattice with two types of sites affecting the rates of birth and death. These
systems exhibit a critical transition between survival and extinction. For
time- dependent background, this transition is equivalent to those found in
homogeneous systems (i.e. to directed percolation). For frozen backgrounds, the
appearance of Griffiths phase prevents the accurate analysis of this
transition. For long times in the subcritical region, spreading remains
localized in compact (rather than ramified) patches, and the average number of
occupied sites increases logarithmically in the surviving trials.Comment: 6 pages, 7 figure
Field theoretic description of charge regulation interaction
In order to find the exact form of the electrostatic interaction between two
proteins with dissociable charge groups in aqueous solution, we have studied a
model system composed of two macroscopic surfaces with charge dissociation
sites immersed in a counterion-only ionic solution. Field-theoretic
representation of the grand canonical partition function is derived and
evaluated within the mean-field approximation, giving the Poisson-Boltzmann
theory with the Ninham-Parsegian boundary condition. Gaussian fluctuations
around the mean-field are then analyzed in the lowest order correction that we
calculate analytically and exactly, using the path integral representation for
the partition function of a harmonic oscillator with time-dependent frequency.
The first order (one loop) free energy correction gives the interaction free
energy that reduces to the zero-frequency van der Waals form in the appropriate
limit but in general gives rise to a mono-polar fluctuation term due to charge
fluctuation at the dissociation sites. Our formulation opens up the possibility
to investigate the Kirkwood-Shumaker interaction in more general contexts where
their original derivation fails.Comment: 12 pages, 9 figures, submitted to EPJ
Debate sobre o artigo de Narvai et al.
English title: Debate on the paper by Narvai et al.Margareth Crisóstomo Portela & Mauricio Teixeira Leite de Vasconcello
Colocalization of the (Pro)renin receptor/Atp6ap2 with H+-AT pases in mouse kidney but prorenin does not acutely regulate intercalated cell H+-ATPase activity
The (Pro)renin receptor (P)RR/Atp6ap2 is a cell surface protein capable of binding and nonproteolytically activate prorenin. Additionally, (P)RR is associated with H+-ATPases and alternative functions in H+-ATPase regulation as well as inWnt signalling have been reported. Kidneys express very high levels of H+-ATPases which are involved in multiple functions such as endocytosis, membrane protein recycling as well as urinary acidification, bicarbonate reabsorption, and salt absorption. Here, we wanted to localize the (P)RR/Atp6ap2 along the murine nephron, exmaine whether the (P)RR/Atp6ap2 is co
Motion of influential players can support cooperation in Prisoner's Dilemma
We study a spatial Prisoner's dilemma game with two types (A and B) of
players located on a square lattice. Players following either cooperator or
defector strategies play Prisoner's Dilemma games with their 24 nearest
neighbors. The players are allowed to adopt one of their neighbor's strategy
with a probability dependent on the payoff difference and type of the given
neighbor. Players A and B have different efficiency in the transfer of their
own strategy therefore the strategy adoption probability is reduced by a
multiplicative factor (w < 1) from the players of type B. We report that the
motion of the influential payers (type A) can improve remarkably the
maintenance of cooperation even for their low densities.Comment: 7 pages, 7 figure
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