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Os indígenas nas minas do ouro : conversão, cativeiro e administração dos trabalhadores (1690-1736).
No full textPrograma de Pós-Graduação em História. Departamento de História, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.Esta pesquisa tem como objetivo principal propor a análise sobre como os indígenas estavam
inseridos nas Minas Gerais em sua fase inicial, através das relações de trabalho. Para analisarmos
o contexto em que se insere a figura indígena nas Minas Gerais e analisar como foi essa chegada
desses agentes no local. O recorte espacial é espaço onde inicia-se as Minas Gerais. O estudo
indicado tem início no ano 1690, devido as primeiras notícias de descoberta do ouro e irá até o
ano de 1736 onde ocorre uma mudança significativa no Regimento das Minas. O referencial
teórico desta pesquisa conta com autores que pertencem a historiográfica mais clássica, no que
diz respeito a tentativa de entender o espaço colonial e os grupos ali inseridos. Articulamos a
História das Minas Gerais e a Indígena para conhecermos os índios que foram agentes
importantes nas minas de ouro do local e das suas fronteiras. Como resultado, evidenciamos a
presença indígena durante os primórdios das Minas Gerais, indo totalmente ao contrário da
historiografia que relata a dizimação deste indígena. Este trabalho irá contra ao apagamento que
é direcionado aos indígenas, o qual foi atuante e tem total relevância no processo de construção
das Minas Gerais dos Setecentos, por sinal, onde a mestiçagem prevalece como uma
característica importante deste território.The main objective of this research is to propose an analysis of how the indigenous people were
inserted in Minas Gerais in its initial phase, through labor relations. In order to analyze the
context in which the indigenous figure is inserted in Minas Gerais and analyze how these agents
arrived in the place. The spatial cut is the space where Minas Gerais begins. The indicated study
begins in the year 1690, due to the first news of the discovery of gold and will go until the year
1736 when there is a significant change in the Regiment of Mines. The theoretical framework of
this research relies on authors who belong to the more classical historiography, with regard to
the attempt to understand the colonial space and the groups inserted therein. We articulate the
History of Minas Gerais and the Indigenous to know the Indians who were important agents in
the gold mines of the place and its borders. As a result, we evidence the indigenous presence
during the early days of Minas Gerais, going completely against the historiography that reports
the decimation of this indigenous. This work will go against the erasure that is directed at the
indigenous people, which was active and has total relevance in the construction process of Minas
Gerais in the seventeenth century, by the way, where miscegenation prevails as an important
characteristic of this territory
Molecular structure of Ru(II)/diphosphine/4,6-dimethyl-2-pyrimidinethiol complexes : a combined experimental and density functional theory study.
No full textReactions of cis-[RuCl2(P-P)(bipy)] precursors with the SpymMe2 ligand (4,6-dimethyl-2-
pyrimidinethiol) yielded complexes of the [Ru(SpymMe2)(P-P)(bipy)]PF6 type, where P-P = 1,2-
bis(diphenylphosphino)ethane (dppe - for complex 1), 1,3-bis(diphenylphosphino)propane (dppp - for
complex 2) and 1,1’-bis(diphenylphosphino)ferrocene (dppf - for complex 3) and bipy = 2,2’-bipyridine.
The new compounds were obtained by displacing the chlorido ligands from the precursors and coordination of one monoanionic 4,6-dimethyl-2-pyrimidinethiol ligand. All complexes were characterized
by spectroscopic, electrochemical and elemental analysis techniques, as well as single-crystal X-ray
diffraction, where the structures of complexes 1, 2 and 3 showed that the SpymMe2 ligand coordinates
to the ruthenium(II) center as bidentated, yielding complexes with the sulfur atom trans positioned
to the nitrogen atom from the bipy ligand. A theoretical study of the structures of the complexes was
performed using the DFT/B3LYP method. Distances and angles of optimized structures agree with X-ray
experimental data. Furthermore, the calculated IR and UV-Vis spectra are compatible with experimental
data. Charge decomposition analysis (CDA) and NBO (natural bond orbitals) charges showed that there
was an overall charge transfer from bipy and P-P ligands to the ruthenium centers. Higher electrochemical stability and 1H and 31P{1H} NMR shifts of 1, 2 and 3 compared with precursors could be explained
by the lower values of calculated molecular orbital energies, NBO charge on atoms and CDA data. Finally,
the structure of the isomers of complexes 1, 2 and 3, considering the sulfur atom trans positioned to
the phosphorus atom, were optimized, showing that they are slightly less stable, presenting total energy
higher, 10.4, 31.5 and 60.5 kJ/mol than 1, 2 and 3, where nitrogen is trans to the phosphorus atom
Atlantic flower–invertebrate interactions : a data set of occurrence and frequency of floral visits.
No full textEncounters between flowers and invertebrates are key events for the functioning of tropical forests. Assessing the structure of networks composed of the
interactions between those partners leads to a better understanding of ecosystem functioning and the effects of environmental factors on ecological processes. Gathering such data is, however, costly and time-consuming, especially
in the highly diverse tropics. We aimed to provide a comprehensive repository
of available flower–invertebrate interaction information for the Atlantic
Forest, a South American tropical forest domain. Data were obtained from
published works and “gray literature,” such as theses and dissertations, as well
as self-reports by co-authors. The data set has 18,000 interaction records
forming 482 networks, each containing between one and 1061 interaction
links. Each network was sampled for about 200 h or less, with few exceptions.
A total of 641 plant genera within 136 different families and 39 orders were
reported, with the most abundant and rich families being Asteraceae,
Fabaceae, and Rubiaceae. Invertebrates interacting with these plants were all
arthropods from 10 orders, 129 families, and 581 genera, comprising 2419 morphotypes (including 988 named species). Hymenoptera was the most
abundant and diverse order, with at least six times more records than the
second-ranked order (Lepidoptera). The complete data set shows
Hymenoptera interacting with all plant orders and also shows Diptera,
Lepidoptera, Coleoptera, and Hemiptera to be important nodes. Among plants,
Asterales and Fabales had the highest number of interactions. The best sampled environment was forest ( 8000 records), followed by pastures and crops.
Savanna, grasslands, and urban environments (among others) were also
reported, indicating a wide range of approaches dedicated to collecting
flower–invertebrate interaction data in the Atlantic Forest domain.
Nevertheless, most reported data were from forest understory or lower strata,
indicating a knowledge gap about flower–invertebrate interactions at the
canopy. Also, access to remote regions remains a limitation, generating sampling bias across the geographical range of the Atlantic Forest. Future studies
in these continuous and hard-to-access forested areas will yield important
new information regarding the interactions between flowers and invertebrates in the Atlantic Forest. There are no copyright restrictions on the data
set. Please cite this data paper if the data are used in publications and
teaching events
Crimes, laughter, and tension: comments on humor in brazilian true crime podcasts.
No full textEste trabalho reflete sobre elementos humorísticos presentes em relatos sonoros sobre crimes reais. Com esse objetivo, identificamos um conjunto de procedimentos retóricos e expressivos relacionados ao humor nos podcasts Modus Operandi e Café com Crime, que caracterizam esses relatos tanto no plano verbal quanto em aspectos especificamente sonoros. A partir disso, apresentamos contribuições à teoria do true crime, que descreve códigos narrativos típicos do gênero, e observamos um esforço desses podcasts para equilibrar a tensão narrativa e a comicidade. Vislumbramos ainda a possibilidade de uma subversão do conceito de alívio cômico para dar lugar a estratégias de salvaguarda dramática com a função de traçar limites ao riso no âmbito desse gênero. Levantamos, por fim, possíveis caminhos para debates éticos.This work reflects on humorous elements present in audio accounts of real
crimes. With this objective, we identified a set of rhetorical and expressive procedures
related to humor in the podcasts Modus Operandi and Café com Crime, which characterize
these accounts both in verbal and in specifically sound aspects. Based on this, we present
contributions to the theory of true crime, which describes typical narrative codes of
the genre, and we observe an effort by these podcasts to balance narrative tension and
comedy. We also see the possibility of subverting the concept of comic relief to give way
to strategies of dramatic safeguarding with the function of setting limits to laughter within
this genre. Finally, we raise possible paths for the ethical debates
Stability analysis of the Chua’s circuit with generic odd nonlinearity.
No full textThis paper analyzes the stability of the Chua’s circuit with generic odd nonlinearity using two traditional analytical tools of the control theory. The first tool is based on the linear approximation of a nonlinear system for the local stability analysis around equilibrium points or manifolds using the Jacobian matrix eigenvalues, which are mapped in the complex plane using the root locus method. The second tool is an extension of linear techniques based on frequency response known as describing function method, which allows analyze effects of nonlinearities in dynamical systems and predict several nonlinear phenomena with reasonable accuracy. These two analytical tools are jointly applied to the stability analysis of an example of this class of nonlinear systems to identify and map its dynamical behavior in parameter space. Numerical investigations based on computational simulations corroborate the theoretical predictions obtained in this stability analysis
Carbon nanotube-cellulose ink for rapid solvent identification.
No full textIn this work, a conductive ink based on microfibrillated cellulose (MFC) and multiwalled carbon nanotubes (MWCNTs) was used
to produce transducers for rapid liquid identification. The transducers are simple resistive devices that can be easily fabricated by
scalable printing techniques. We monitored the electrical response due to the interaction between a given liquid with the carbon
nanotube–cellulose film over time. Using principal component analysis of the electrical response, we were able to extract robust
data to differentiate between the liquids. We show that the proposed liquid sensor can classify different liquids, including organic
solvents (acetone, chloroform, and different alcohols) and is also able to differentiate low concentrations of glycerin in water
(10–100 ppm). We have also investigated the influence of two important properties of the liquids, namely dielectric constant and
vapor pressure, on the transduction of the MFC-MWCNT sensors. These results were corroborated by independent heat flow mea-
surements (thermogravimetric analysis). The proposed MFC-MWCNT sensor platform may help paving the way to rapid, inexpensive, and robust liquid analysis and identification
Vulnerability analysis in complex networks under a flood risk reduction point of view.
No full textThe measurement and mapping of transportation network vulnerability to natural
hazards constitute subjects of global interest for a sustainable development
agenda and as means of adaptation to climate change. During a flood, some
elements of a transportation network can be affected, causing the loss of lives.
Furthermore, impacts include damage to vehicles, streets/roads, and other
logistics services - sometimes with severe economic consequences. The
Network Science approach may offer a valuable perspective considering one
type of vulnerability related to network-type critical infrastructures: the
topological vulnerability. The topological vulnerability index associated with an
element is defined as reducing the network’s average efficiency due to removing
the set of edges related to that element. In this paper, we present the results of a
systematic literature overview and a case study applying the topological
vulnerability index for the highways in Santa Catarina (Brazil). We produce a
map considering that index and areas susceptible to urban floods and
landslides. Risk knowledge, combining hazard and vulnerability, is the first pillar
of an Early Warning System and represents an important tool for stakeholders of
the transportation sector in a disaster risk reduction agenda
Study of requirements for datacenters and insdustrial rooms for technology and automation systems.
No full textNo meio industrial é de clara importância que o ambiente em que os sistemas de tecnologia (servidores, switches, roteadores, etc.) e de automação (por exemplo, PLC) estejam devidamente suportados, evitando impactos por problemas de infraestrutura, como falta de energia e falha em sistemas de climatização (gerando temperaturas inadequadas para esses equipamentos). Para isso, existem diversos equipamentos e sistemas para proteger e monitorar essas salas, porém, no Brasil não há normas estabelecendo padrões a serem seguidos para que uma sala de tecnologia ou um Datacenter tenham a disponibilidade adequada com os sistemas suportados nesses. Internacionalmente a normatização não é suficiente e por vezes traz pontos que não são aplicáveis a outros países. Dessa forma, estabelecer padrões para essas salas traz um benefício significante às indústrias, uma vez que estas estão cada vez mais utilizando tecnologias para seus sistemas de produção, segurança e emergências, assim necessitando de uma disponibilidade máxima, enquanto outras salas podem suportar apenas sistemas de pequena complexidade e/ou que não tem a mesma criticidade para a empresa, não necessitando de um nível tão alto de disponibilidade.Within the industrial environment it is of evident importance that the environment in which technology systems (such as servers, switches, routers, etc.) and automation systems (such as PLCs) are properly supported, to avoid impacts due to infrastructure problems, such as lack of energy, failure in HVAC systems (generating higher temperatures than recommended for this equipment). To prevent these problems, the industries may have several equipment and systems to protect and monitor these rooms. However, there is no standard in Brazil establishing models to be followed on this subject so that a technology room or a Datacenter has an adequate availability for the systems supported on it, and even outside Brazil, the standardization may not be adequate to the particularities from different countries and add some that may not be significant for others. Establishing standards for these rooms bring a significant benefit to industries, since these are increasingly using technologies for their production, security, and emergency systems, thus requiring maximus availability, while other rooms may only support small complexity systems and/or that do not have the same criticality for the company, therefore they do not need such a high level of availability
Simple experiment for modeling the reaction interface in solids decomposition.
No full textEn concordancia con el concepto de interdisciplinaridad, el presente trabajo propone un experimento sencillo para la
enseñanza de reacciones de descomposición de sólidos, mediante la simulación de la evolución geométrica de
paralelepípedos de naftaleno sometidos a sublimación. El modelamiento geométrico de las proyecciones de las caras
del objeto de ensayo mediante las curvas de Lamé (también denominadas superelipses) permite calcular el volumen
del superelipsoide correspondiente, proporcionando una cuantificación adecuada en la variación de la masa muestral
del naftaleno. El procedimiento experimental planteado evidencio ser una herramienta fácil y esclarecedora para
realizar clases prácticas en laboratorios mínimamente equipados, con el objetivo de aprender tanto reacciones de
descomposición de sólidos, como también de técnicas de modelamiento matemático de interfases en reacciones
heterogéneas, aplicando curvas de Lamé.In line with the concept of interdisciplinarity, the present work proposes a simple experiment to teach solid
decomposition reactions, through the geometric evolution of naphthalene parallelepipeds submitted to sublimation.
Geometric modeling of the specimen's face projections by the Lamé curves (also called superelipses) allows the
calculation of the volume of the corresponding superelipsoid, resulting in adequate quantification of the evolution of
the naphthalene sample mass. The proposed experimental procedure has proved to be a simple and elucidative tool
for carrying out practical classes in the laboratory, minimally equipped, aiming at learning both solid decomposition
reactions and mathematical modeling techniques for heterogeneous reaction interfaces, using Lamé curves
The difficulties faced in the labor market and the well-being of generation Z.
No full textA presente pesquisa teve como objetivo compreender como os indivíduos pertencentes à geração Z buscam contornar as dificuldades enfrentadas no mercado de trabalho e como seu bem-estar é afetado nesse processo. Como método, foram realizadas 12 entrevistas em profundidade e os dados coletados foram analisados por meio da técnica de Análise de Conteúdo. Examinando os resultados obtidos, constatou-se que, diante das dificuldades enfrentadas no processo de busca por emprego, a ampla maioria dos entrevistados dedica-se à continuidade dos estudos para compensar a falta de experiência. Verificou-se ainda que vários dos jovens entrevistados, devido à necessidade de auferir alguma renda durante o período de desemprego, passaram a realizar trabalhos informais, em áreas totalmente distintas de sua formação. Finalmente, concluiu-se que, devido ao desemprego prolongado, os sujeitos da pesquisa passaram a se sentir aflitos, ansiosos e insatisfeitos com sua trajetória profissional.The present research aimed to understand how individuals belonging to generation Z seek to overcome the difficulties faced in the labor market and how their well-being is affected in this process. As a method, twelve in-depth interviews were carried out and the data collected were analyzed using the Content Analysis technique. Examining the results obtained, it was found that, given the difficulties faced in the job search process, the vast majority of interviewees dedicate themselves to continuing their studies to compensate for the lack of experience. It was also found that several of the interviewed, due to the need to earn some income during the period of unemployment, began to perform informal jobs, in areas totally different from their academic formation. Finally, it was concluded that, due to prolonged unemployment, the research subjects started to feel distressed, anxious and dissatisfied with their professional trajectory