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Tecnologia e Política: a modernização naval na Argentina e Brasil, 1900-1930
(Universidade Federal de São Carlos, 2018-10-05) Waldmann Júnior, Ludolf; Martins Filho, João Roberto; https://lattes.cnpq.br/8157447462904324; https://lattes.cnpq.br/5064104684523336
This thesis seeks to analyse the process of technological modernization of the Argentine and Brazilian navies between 1900 and 1930. During this period, the rivalry between the two great South American countries was fundamental in their naval modernization policy. Argentina, which until then had no relevant fleet, expanded her naval forces in the late nineteenth century when it was involved in an arms race with Chile. In this process, she changed the regional naval balance, surpassing the Brazilians, who responded by approving new naval programs in 1904 and 1906. Thus, a new regional arms race began, centred on the dreadnoughts and that almost led to the emergence of a war. The naval competition gradually lose momentum after 1910, effectively ending with the outbreak of the World War I. The accelerated technological progress in this conflict quickly made both navies obsolete, which then adopted distinct positions: Argentina remained neutral, while Brazil supported the Allied cause, getting help to prepare its fleet, but unable to update it. In the post-war, despite international pressures for disarmament, the South Americans sought to modernize their navies again, but only the Argentineans were able to do so. Considering this period, our objectives are: 1) to understand the policy of naval acquisitions of the two countries from the perspective of their foreign policy; 2) understand how the decisions of naval modernisation were related to the domestic political dynamics in the two countries, focusing on civil-military relations; 3) analyse the naval decision-making process, identifying internal divergences regarding technological choices as well as the impacts that acquired equipment had on the respective navies. The diplomatic and defence policy of Argentina and Brazil was very marked by the regional dynamics, where a competition between these states was based on a regional balance of power perspective that influenced the decisions of naval modernization. In addition to the influence of foreign policy, the domestic and institutional spheres of these navies also affected the process by which they made their acquisitions. The institutional arrangements and patterns of civil-military relations existing in both these periods influenced the process of naval modernization, especially the time of choice to renew the fleet. Given the relative autonomy of decision-making and little political-institutional interest of the rest of the state and society in participating in the process of elaboration of naval programs in the two countries, modernization policies were largely the result of internal decisions in the navies, where there were significant divergences.
Caracterização temporal da fadiga diafragmática e dos efeitos do treinamento muscular inspiratório durante o exercício de alta intensidade em adultos saudáveis
(Universidade Federal de São Carlos, 2018-10-05) Archiza, Bruno; Silva, Audrey Borghi; https://lattes.cnpq.br/4855616925791895; https://lattes.cnpq.br/1129428210391656
The diaphragm is the principle muscle of inspiration and is subject to fatigue during whole-body exercise at intensities above 85% of maximal oxygen consumption (V̇O2). Exercise-induced diaphragmatic fatigue (DF) generates higher perceptions of dyspnea and limb fatigue, it onsets the respiratory muscle metaboreflex and, consequently, limiting high-intensity exercise (HIE). Inspiratory muscle training (IMT) is highly efficient to provide gains in respiratory muscle strength (RMS), and to promote greater HIE and athletic performance. This thesis is composed by two studies. The objective of Study I was to investigate temporal characteristics of exercise-induced diaphragmatic fatigue (DF) during HIE in healthy adults. Ten healthy men were recruited in the initial screening and 8 were included in the final analysis. Initially, anthropometrics and spirometry were assessed, followed by a cardiopulmonary exercise test (CPET) in a cycle ergometer. Another 3 tests were performed using the Δ60% method to calculate the workload. The first was performed to time-to-exhaustion (TTE) while the other 2 were randomly applied to 50 and 75% of TTE. DF was assessed using the balloon catheterization method and through the calculation of transdiaphragmatic twitch pressure after cervical magnetic stimulus. DF was found from 75% TTE (P<0,05); also, a strong and significant correlation was found between fatigue and diaphragmatic force output (r=0,785, P<0,001). We concluded that DF occurs during HIE and its magnitude increases as the work of breathing do so. Therefore, the diaphragmatic capacity to generate force and pressure becomes progressively smaller during HIE. In Study II we sought to investigate the effects of IMT on HIE tolerance, respiratory and peripheral muscles oxygenation, and performance during a repeated sprints ability test (RSA) in female soccer athletes. Eighteen athletes were included in the final analysis. Participants were randomly assigned into two groups: IMT (IMT, n=10), and sham (SHAM, n=8). As initial evaluation: anthropometrics, spirometry at rest, maximal mouth inspiratory (MIP) and expiratory static pressures assessment, CPET in a treadmill, time-to-exhaustion (TTE) constant load exercise test, and RSA test. After 60 sessions of intervention (2x/day, 5 days/week, 6 weeks; IMT and SHAM training at 50 and 15% MIP, respectively), the same tests were applied. A greater HIE tolerance was found post-intervention on both groups (TTE, P<0,05), however, only IMT group presented better respiratory and peripheral muscles oxygenation during high-intensity exercise (P<0,05). Both groups showed improvements on RSA test (both P<0,05). Such results indicate the potential role of IMT at better oxygenation and blood supply to peripheral muscles during HIE, also presenting a positive impact on inspiratory muscles strength, exercise tolerance, and RSA performance in women’s soccer athletes.
Dinâmica e diversidade das comunidades microbianas em cavernas tropicais do Brasil Central
(Universidade Federal de São Carlos, 2018-10-05) Paula, Caio César Pires de; Bichuette, Maria Elina; https://lattes.cnpq.br/8453043393798516; Seleghim, Mirna Helena Regali; https://lattes.cnpq.br/5998337634888263; https://lattes.cnpq.br/4895747549423676
Subterranean environments are generally considered extreme oligotrophic and have specific characteristics that determine the local microbiota, such as: different humidity conditions, temperature and nature of nutritional resources. Although studies on environmental microbial diversity have made considerable advances, few researches have investigated the terrestrial microbiota of subterranean environments, mainly in tropical regions. Considering that the diversity and dynamics of the microorganisms of these environments is practically unexplored, this study had as aim to analyze, firstly, the current scenario of conservationist policies in Brazilian caves and to discuss the trophic level in tropical and temperate caves. In addition, in order to characterize microbial communities in tropical caves, the composition and structure of microbial biodiversity (bacteria and fungi) and environmental conditions (physicochemical parameters) were evaluated in all samples sampled in three caves of a Brazilian Conservation Unit (State of Terra Ronca - PETER, São Domingos, GO). Brazilian legislation was consulted on the use and conservation of caves, concentrations of organic carbon and total nitrogen were measured in tropical caves, as well as microbial attributes (biomass and respiration) to understand the dynamics of the microbial community in relation to the availability of organic matter. Composition and structure of microbial communities along a trophic gradient (surface > cave entrance > subterranean) was evaluated in each cave studied. We used the sequencing of 16S and ITS (rRNA) genes to access the biodiversity of fungi and bacteria. The use of microbial studies in the conservation policies of cave dwellers environments was discussed from the data obtained in this research. Considering published and new data on the quantity and quality of dissolved organic matter (carbon and nitrogen) in tropical and temperate caves, much care is needed when considering all the subterranean environments as extreme oligotrophic. Actinobacteria and Proteobacteria (mainly Alpha and Gamma) were the most frequent bacterial groups in the caves studied. Among the fungi, large proportions of Actinomycetes were observed in subterranean environments, mainly in dry period. Although most microbial communities are characterized by detritivorous microorganisms, some microorganisms known for chemoautotrophic activity (such as Beggiatoa) were observed in this study. The large number of uncultured bacteria and unidentified fungi in tropical caves is remarkable, indicating the great potential of this habitat to house new species of microorganisms. Structure and composition of the microbial communities in the studied caves were more dissimilar among them in subterranean environments than in surface environments. This dissimilarity among the microbial communities confers a singularity to each cave studied. Finally, microbial community in one of the studied caves showed evidence of the Halobacteriacea family dominance in entrance cave, probably due to its environmental conditions, such as high salinity of the substrate. The data obtained in this study enrich the knowledge of microbial biodiversity, clarify knowledge about the structure and dynamics of microbial communities in tropical caves and contribute to future proposals for cave environments conservation.
Aspectos filogeográficos de Leporinus cf. friderici e da distribuição da diversidade genética em Leporinus cf. friderici Paraná e Megaleporinus obtusidens na bacia do Alto Paraná
(Universidade Federal de São Carlos, 2018-10-05) Santos, Rosane Silva dos; Freitas, Patrícia Domingues de; https://lattes.cnpq.br/5647631868534064; https://lattes.cnpq.br/5600063172203814
The megadiversity of the Neotropical ichthyofauna has been associated to recent diversification processes, reflecting in subtle or lacking morphological differentiation between species, challenging the classical taxonomic identification. Leporinus friderici occurs in several river basins of South America, and its nominal taxonomic validity has been questioned. Its wide distribution within Brazilian Shield suggests that this species could be genetically structured among the hydrographic basins, despite a sharp morphological similarity. In this study, we performed phylogenetic analyses, based on three nuclear (RAG1, RAG2 and Myh6) and two mitochondrial (COI and Cytb) markers, in specimens morphologically similar to L. friderici and related species from different hydrographic basins in South America. Our phylogenetic tree identified four well-supported clades, point out to the existence of taxonomic inconsistencies within this fish group. A clade named L. cf. friderici sensu stricto included eight MOTUs (Molecular Operational Taxonomic Units) recently diversified in the Brazilian Shield basins. These results were also confirmed by a single-gene species delimitation analysis. It is suggested that this clade includes a species complex, characterizing taxonomic uncertainties. Another clade recovered only L. friderici from the Suriname rivers, validating this nominal species in its type locality. A third no-named clade, characterized by deeper species divergence, recovered five different nominal species interleaved with other undescribed forms previously also recognized as L. cf. friderici, indicating taxonomic errors. The fourth clade only included L. taeniatus. Our results showed a complex scenario involving the morphotype L. cf. friderici and allowed us to address aspects related to evolutionary diversification of this fish group and historical processes involved with, highlighting the importance of revealing hidden biodiversity for the taxonomy and conservationist action plans of these fish.