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Evolução cromossômica e diversidade genética em espécies de peixes da família Arapaimidae (Teleostei: Osteoglossiformes)
(Universidade Federal de São Carlos, 2019-07-12) Oliveira, Ezequiel Aguiar de; Cioffi, Marcelo de Bello; https://lattes.cnpq.br/0242034365085727; https://lattes.cnpq.br/3035501906153908
The Neotropical region exhibits the largest diversity of freshwater fishes in the world and the demographic history of several taxa is related to the geomorphological and climatic history of this region. Among the Osteoglossiformes, the Arapaimidae family is represented by only two genera, with a South American representative Arapaima and another African Heterotis, an important ichthyological group that still has lacked genetic and cytogenetic studies. Therefore, the present work with the use of advanced population genomics tools, selection of demographic models by machine learning, conventional and molecular cytogenetics analysis, aimed at developing a broad understanding of the chromosomal, molecular and phylogeographic diversity of these species. We aimed to better clarify the evolutionary events that shaped the demographic history of this fish group. For that, South American and African representatives of Arapaimidae, namely Arapaima (four natural populations of the Am basin, three of the To-Ar basin and three fish farms) and Heterotis niloticus (a population of the Oluwa River in Nigeria) were examined. The species differed significantly by means of diploid chromosome numbers, with 2n = 56 found in Arapaima and 2n = 40 exhibited by H. niloticus. However, these species presented some general tendencies shared by other Osteoglossiformes analyzed so far, regarding the presence of only one pair of chromosomes bearing 18S and 5S rDNA sites and karyotypes dominated by acrocentric-submetacentric chromosomes, thus corresponding to hypothetical karyotype patterns ancestral to teleosts. In addition, their genomes showed remarkable divergence in terms of repetitive DNA content and distribution as revealed by Comparative Genomic Hybridization (CGH). On the other hand, genomic diversity of single-copy sequences (SNPs), retrieved through principal component analysis (PCA), based on alleles obtained by the DArTseq procedure, demonstrated a very low genetic distance between these genera. These data provided a clear view of the genetic diversity between African and South American Arapaimidae species and were highly consistent with the chromosomal, geographic and historical data, helping to understand its evolutionary diversification. Concerning the investigations of the genus Arapaima in South America, we observed a higher general level of genetic diversity in the Am populations when compared to the one observed in the To-Ar basin. In addition, a high genetic differentiation between the populations of the different basins was observed. By including samples of fish farming, the most likely ancestry of the used breeding herds was revealed, raising concerns about the use of broodstocks outside the distribution of their genetic grouping. No significant chromosome differentiations in the karyotypic structure and repetitive DNA compositions among the studied Arapaima populations was observed. Although the main routes for Arapaima colonization in South America are still unclear, the model selection from convolutional neural networks (CNN) applied to our empirical data indicated a scenario in which the Am basin was the first to be colonized, followed by the To-Ar one. Other studies should focus on a wider historical biogeographic reconstruction of the order Osteoglossiformes, which may potentially explain its relationship with the Gondwana break-up and the presence of this taxon in South America.
Crescimento de seis espécies madeireiras nativas da mata atlântica sob diferentes intensidades de luz
(Universidade Federal de São Carlos, 2019-07-12) Barros, André Junqueira; Loiola, Priscilla de Paula; https://lattes.cnpq.br/2691455603546958; Viani, Ricardo Augusto Gorne; https://lattes.cnpq.br/3250752369062840; https://lattes.cnpq.br/7443749852682001
The history of degradation has generated millions of hectares that demand forest restoration by landowners in the Atlantic Rain Forest and other tropical regions of the world. However, the high cost of the projects inhibits large-scale forest restoration and one way to overcome this barrier is the develop of restoration models that foresee timber production. The objective of this work was to evaluate the development of six native species of the Atlantic Rain Forest that have potential to produce timber (Anadenanthera colubrina, Balfourodendron ridelianum, Cordia trichotoma, Astronium graveolens, Cariniana legalis e Parapiptadenia rigida), planted in a forest restoration area of five years, in Araras-SP, under different intensities of light. We expected that the increase in light availability would lead to higher growth of timber species. The treatments consisted of chemical thinning (standing death) of 0, 30, 60 and 100% of the basal area of the covering trees. In 20 plots of 600 m² each, photosynthetically active radiation (PAR) and canopy opening were used to validate the chemical thinning technique and to relate them to each other and with silvicultural attributes (height, diameter and stem quality) of individuals under different intensities of light. The height, diameter at the soil level and stem quality of 1.000 individuals were sampled before and one year after treatments, to analyze growth in a shaded environment and relative growth rate after thinning, and the infestation of invasive grasses and ruderal species under different levels of light. The chemical thinning created light treatments, and the canopy opening, and PAR sampling methods showed a positive correlation. The growth of the evaluated species was slow in a shaded environment, with a positive result for C. legalis and negative for B. riedelianum. The levels of thinning affected the relative growth in trunk diameter of the species and, individually, C. legalis and C. tricochoma presented differences for relative growth rate in height and diameter, and B. riedelianum for diameter, due to the levels of thinning and PAR. The thinning provides greater light input in the understory and this may favor the growth of some species, without influencing others. Therefore, the decision to use practices to increase light levels in the understory of forest restoration plantations is species dependent.
Dinâmica de EDP parabólicas locais ou não locais: existência, unicidade e comportamento assintótico de solução
(Universidade Federal de São Carlos, 2019-07-12) Luna, Tito Luciano Mamani; Madeira, Gustavo Ferron; https://lattes.cnpq.br/1540196066117667; https://lattes.cnpq.br/9286342294400168
This work is dedicated to the study of dynamical properties of some partial differential equations (PDE, for short) of parabolic type, local or nonlocal ones. We prove existence, uniqueness and establish the asymptotic behavior, for large times, for two classes of PDE. Namely, a (nonlocal) parabolic equation with a Kirchhoff term and flux boundary condition and two parabolic PDE driven by the p-Laplacian with logistic terms involving potentials and weights which may be indefi nite and unbounded. First we prove existence and continuous dependence on data for the PDE with Kirchhoff term using Faedo-Galerkin method and a suitable change of variables. Some sufficient conditions are given to ensure uniqueness of solution. Concerning asymptotic behavior, we show that the omega limit set of each (semi) orbit contains, at least, one stationary solution. We then study stability of local minima of the associated energy functional showing first a result on asymptotic stability of a global minimum for the energy. We also prove a sufficient condition for the existence of isolated local minimum of the energy functional, which is proved to be an asymptotically stable stationary solution in a suitable neighborhood. Finally we determine the dynamics of positive solutions with bounded initial datum for two classes of parabolic PDE driven by the p-Laplacian with indefi nite and unbounded potentials and logistic sources having weights which are also indefi nite and unbounded. The boundary conditions appearing are also of flux type (linear or nonlinear). The asymptotic stability properties of the stationary solutions are described using principal eigenvalues of some elliptic eigenvalue problems involving a parameter of the original PDE. Those eigenvalue problems are also studied herein in order to be used as a tool for obtaining our results due to the low regularity assumptions on their coeficients from the viewpoint of the literature.
A construção da criticidade na perspectiva do letramento. Reflexões a partir da análise de uma experiência em sala de aula
(Universidade Federal de São Carlos, 2019-07-12) Martarello, Paulo Francisco; Míguez, Antón Castro; https://lattes.cnpq.br/6829358449068280; https://orcid.org/0000-0003-0592-7270
El objetivo de este trabajo es analizar cómo se construye la criticidad desde la perspectiva de la literacidad, en el contexto del aula (de lengua extranjera), a partir de reflexiones producidas acerca de mi experiencia como profesor en formación y en período de prácticas. Para ello, desarrollo una investigación de carácter narrativo, según lo que propone Vera Menezes (2006), en que analizo mis registros (planes de clases, diarios reflexivos y registros personales) durante el período de prácticas obligatorias de la carrera de Licenciatura en Letras, ocasión en que pude ofrecer un curso de corta duración de lengua española a adolescentes de una escuela pública. Los análisis emprendidos y las reflexiones construidas señalan la importancia de que el educador (en el ámbito de la educación lingüística) piense sus acciones pedagógicas involucradas a una agenda de combate a las desigualdades y de promoción de una ciudadanía crítica, plena y solidaria, comprometidas con el desarrollo de la autonomía y la criticidad de los estudiantes.
Anitta ou Larissa? Da Poderosa à Malandra: Performatividades e Identidades que promovem o empoderamento feminino no funk brasileiro
(Universidade Federal de São Carlos, 2019-07-12) Cardeal, Fernanda Rebeca de; Míguez, Antón Castro; https://lattes.cnpq.br/6829358449068280; https://lattes.cnpq.br/1496316750793018
La investigación propone reflexiones acerca del funcionamiento del lenguaje en relación a los discursos de empoderamiento femenino encontrados en las performatividades de la cantante e intérprete Anitta, así como las varias identidades sociales que la integran como sujeto político en la sociedad brasileña. Al representar el estilo Funk – género musical contemporáneo – la artista presenta interpelación política y social relevante para los estudios de teorías feministas y de empoderamiento. A partir de un análisis documental asistido por estudios de performatividad e identidad, la investigación presenta aproximaciones para reflexiones de análisis de los objetos seleccionados, compuesto por dos performatividades de Anitta: “Show de las Poderosas” y “Vai Malandra”, bajo la perspectiva del lugar de habla, del empoderamiento y del feminismo. A partir de las discusiones propuestas a lo largo de la investigación, busco resultados teórico-reflexivos significativos, pues considero los objetos de investigación empíricamente contemporáneos y transgresores.
Análise de metais potencialmente tóxicos em ambientes aquáticos (Da Água e dos insetos da ordem Odonata) para biomonitoramento ambiental
(Universidade Federal de São Carlos, 2019-07-12) Ribeiro, Simone Maria; Toppa, Rogério Hartung; https://lattes.cnpq.br/0673898572494729; Oliveira, Luciana Camargo de; https://lattes.cnpq.br/6238603150964753; https://lattes.cnpq.br/3109727842759309
Potentially toxic metals are among the most common contaminants in waters and their origin may be both natural and anthropogenic. As soon as they come into contact with the aquatic ecosystem, the metals can be transported to the various compartments of the environment, such as soil, sediment, plants and animals, and may become bioaccumulative. With the increase of activities of anthropic origin and the degradation of water resources, biomonitoring becomes an effective way to expose various types of stress that may occur in the environment, serving as an alarm for declines in the quality of the environment and populations. With the determination of the adverse effects of the presence of contaminants in water bodies, it is becoming increasingly important to indicate environmental disturbances from possible contaminating sources such as agriculture. The objective of this study was to determine the levels of Zn2+, Cd2+, Cu2+, Co2+, Pb2+, Cr2+, Mn2+, Al3+ in the water and larvae of the order Odonata in dams 1 and 2, related to the conventional and organic planting of a plantation orange. The collected samples were previously digested and subjected to the analysis of determination of the potentially toxic metals using the atomic emission spectrometry equipment with microwave plasma (MP-AES). The water samples indicated for some metals a concentration above the limit allowed by CONAMA Resolution n° 357/2005, in the following order Cu2+> Pb2+> Mn2+ in both dams near conventional and organic cultivation. Cr ions were observed only in dam 1 (close to conventional planting) and Al ions in dam 2 (close to organic planting). In the Odonata larvae, the presence of metals Zn2+> Cu2+> Pb2+> Mn2+ was observed in both dams close to conventional and organic cultivation. All other metals were found in dams and larvae, even in small concentrations. It is concluded that the insects of the order Odonata absorb considerable concentrations of metals in the organism, the metals found in the Odonata resemble the metals found in the water, and it can be reinforced the concept that the Odonata are important indicators to monitor contaminations of metals in agricultural areas.