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Termodinâmica de buracos negros de Schwarzschild
(Universidade Federal de São Carlos, 2018-05-28) Santi, Natali Soler Matubaro de; Santarelli, Raphael; https://lattes.cnpq.br/3591899759824320; https://lattes.cnpq.br/3869697280207128
This dissertation consists of a review about some aspects of Schwarzschild black hole thermodynamics and includes a discussion related to the temporal evolution of the masses of these black holes in a thermodynamic context. We started studying some aspects of general relativity, verifying some properties first in Minkowski space-time, from perspective of an accelerated observer, and then in Schwarzschild space-time. After that we moved to quantum field theory in curved spaces, starting with the Unruh effect as a motivation for the Hawking radiation, which is the main goal of this work, deducing the temperature for a Schwarzschild black hole. Later we presented the laws of the black hole thermodynamics and an analogy with classical thermodynamics laws. Lastly, we discussed the temporal evolution of the masses of Schwarzschild black holes for different initial values and environment conditions: empty space, cosmic microwave background with constant temperature and with temperature varying with time according with the eras of the universe.
Germinação de sementes de Rubus sellowii e micropropagação de Morus nigra
(Universidade Federal de São Carlos, 2018-05-28) Duarte, Willian Naves; Cardoso, Jean Carlos; https://lattes.cnpq.br/3681181863704059; https://lattes.cnpq.br/3146159019158911
Sexual and vegetative propagation are the main methods of perpetuating plant species. Despite its importance in propagation, seeds of some species do not germinate even under favorable conditions, as is the case of seeds of the genus Rubus, situation called dormancy. Experiments were carried out to characterize and overcome dormancy in R. sellowii seeds. During the seed imbibition process, was observed a barrier for water absorption. For the chemical scarification of the seeds, NaClO and H2SO4 were evaluated. NaClO was not efficient for tegument scarification. Treatment with H2SO4 for 20 min showed 50% seed germination and a higher rate of germination. It was also carried out the sowing, without scarification, in a tray containing substrate the base of pinus bark and kept in greenhouse. Seedling emergence started 70 days after sowing, reaching 50% after 370 days. Experiments were also carried out with the micropropagation of Morus nigra, considering the nonviability of commercial seed propagation. It was observed that in vitro cultivation of explants in the absence of phyto-regulators produced seedlings ready for the acclimatization phase. In the acclimatization, we tried to verify the best growing environment (growth room or greenhouse) and in vitro culture time. Growing for 28 days in the growing room resulted in plants with higher height (9.2 cm), number (4.8) and leaf diameter (3.23 cm), an essential condition for efficient acclimatization. For the somatic embryogenesis, calli of nodal explants of M. nigra were obtained with the use of naphthalene-acetic acid (ANA) or benzyladenine (BA), under light or dark conditions. Both presented similar callus induction rates. For the induction of somatic embryogenesis, twelve culture media were used for the induction of embryogenic calli. It was possible to obtain them in media containing BA, 2,4-D and coconut water. These were cultivated in liquid medium of maturation, in which they presented the development of globular structures of cream coloring. These globular structures have multiplied, acquiring green pigmentation when grown on sucrose or glucose as aviii carbon source. However, there was no subsequent development or regeneration in seedlings.
Metapesquisa em ensino e aprendizagem de línguas: um estudo modelar com foco em interação
(Universidade Federal de São Carlos, 2018-05-28) Freitas, Mirelle da Silva; Viana, Nelson; https://lattes.cnpq.br/6252579012192711; https://lattes.cnpq.br/5336541959141675
The growing number of academic studies in all fields of study and, therefore, in Language Teaching (LT), raises an issue about how to synthesize systematically and in an organized way this myriad of knowledge in a way that allows and boosts science advances, so that investigations (and researchers themselves) do not become a plethora of unordered information – which can result in waste of time and/or investment in areas well settled. Hence, research synthesis arises as a methodology which is capable to fulfill this need, as its aim is to systematically organize knowledge about a certain theme and make it available for the ones interested in it. This study presents research synthesis as a research methodology, highlighting its features and providing directions for those who are interested in doing this kind of investigation under the qualitative paradigm. In order to do so, beyond characterizing this methodology, it also presents a study on interaction, clarifying and critically discussing the steps that should be taken in a qualitative research synthesis. The theme resulted from the growing number of studies in language teaching and its consequent need to organize the information in them, so that LT research can better help the development of theories and practices regarding language learning. This study highlights how organizing information systemically (through research synthesis) can broaden the content and effectiveness of knowledge developed in LT, so that we can circumvent: wasting productive time and resources, gathering practical knowledge distributed in university libraries; and, consequently, help interpret research results, which could help comprehension and impact practice. Furthermore, the data analyzed has its focus on interaction and shows the urge to rethink language pedagogical practices, so that language classrooms can enable students to be active subjects in society, connecting language teaching and language use. Research synthesis and interaction ‘in the wild’ demand more studies to enable the field to contribute more to the language learning area in countries where we face great challenges in this field.