169 research outputs found
A legitimidade das realezas franca e visigótica nas obras de Gregório de Tours e Isidoro de Sevilha (séculos VI-VII)
No decorrer do século V, o Império Romano Ocidental desagregou-se, dando lugar a diversos reinos ditos germânicos. Uma das preocupações fundamentais dos governantes desses regni era a de legitimar o seu poder, ou seja, fazer com que sua autoridade fosse reconhecida tanto pela nobreza quanto pela população em geral. Esta tarefa mostrava-se desafiadora pelos seguintes motivos: primeiramente, estes reinos formaram-se em locais que durante séculos estavam submetidos à autoridade romana, sendo assim, as formas e símbolos de governo de origem imperial não podiam ser desprezadas. Além disso, muitos desses reinos sofriam de uma instabilidade interna crônica, onde a autoridade do monarca era frequentemente contestada. Somada a isto está a presença do Império Romano do Oriente, que, sob Justiniano, retomou áreas consideráveis do Mediterrâneo Ocidental. Devido a tais dificuldades, os reis bárbaros voltaram-se para a Igreja, visando buscar uma legitimidade espiritual para seu poder. Os bispos viam no monarca um poderoso aliado em seus combates contra o paganismo e as heresias. Desse modo, houve uma aproximação entre rei e episcopado, em que os bispos tornaram-se importantes legitimadores da autoridade do monarca. Na presente dissertação, estudaremos as concepções episcopais sobre o rei e suas funções nas obras de dois bispos: Gregório de Tours (538-594) e Isidoro de Sevilha (560-636), que viveram, respectivamente, na Gália merovíngia e no Reino Visigótico católico
Radial force control of Multi-Sector Permanent Magnet machines considering radial rotor displacement
A mathematical model enabling to predict the electromagnetic x-y forces and torque for a given input current in a Multi-Sector Permanent Magnet Synchronous (MSPMS) machine is presented. The rotor static eccentricity is also accounted and the analytical calculations are validated by means Finite Element Analysis (FEA). Furthermore, a novel force and torque control is proposed based on input current minimization and is applied to suppress the Unbalanced Magnetic Pull (UMP) caused by the rotor eccentricity. The effective operation of the force suppression technique is verified by means of FEA
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Emerging research and future pathways in digital supply chain governance
Over the past 20 years, the management of supply chain (SC) relationships and, particularly,
related governance theories, instruments and mechanisms have received increasing attention
in operations management research (cf. Pilbeam et al., 2012; Bonatto et al., 2020). The
emergence of fragmented and globally dispersed supply chains has laid the foundation for
various forms of interorganizational governance (Gereffi et al., 2005) that utilize contractual
and relational mechanisms to balance interdependencies and individual interests in a way
that allows effective collaboration and control for improved performance (Pilbeam
et al., 2012)
Reduction of the ATPase inhibitory factor 1 (IF1) leads to visual impairment in vertebrates
In vertebrates, mitochondria are tightly preserved energy producing organelles, which sustain nervous system development and function. The understanding of proteins that regulate their homoeostasis in complex animals is therefore critical and doing so via means of systemic analysis pivotal to inform pathophysiological conditions associated with mitochondrial deficiency. With the goal to decipher the role of the ATPase inhibitory factor 1 (IF1) in brain development, we employed the zebrafish as elected model reporting that the Atpif1a−/− zebrafish mutant, pinotage (pnttq209), which lacks one of the two IF1 paralogous, exhibits visual impairment alongside increased apoptotic bodies and neuroinflammation in both brain and retina. This associates with increased processing of the dynamin-like GTPase optic atrophy 1 (OPA1), whose ablation is a direct cause of inherited optic atrophy. Defects in vision associated with the processing of OPA1 are specular in Atpif1−/− mice thus confirming a regulatory axis, which interlinks IF1 and OPA1 in the definition of mitochondrial fitness and specialised brain functions. This study unveils a functional relay between IF1 and OPA1 in central nervous system besides representing an example of how the zebrafish model could be harnessed to infer the activity of mitochondrial proteins during development
Direct flux and current vector control for induction motor drives using model predictive control theory
The study presents the direct flux and current vector control of an induction motor (IM) drive, which is a relatively newer and promising control strategy, through the use of model predictive control (MPC) techniques. The results highlight that the fast flux control nature of direct flux control strategy is further enhanced by MPC. Predictive control is applied in two of its variants, namely the finite control set and modulated MPC, and the advantages and limitations of the two are underlined. This work also highlights, through experimental results, the importance of prioritising the flux part of the cost function which is particularly significant in the case of an IM drive. The performance of the MPC-based approach is compared with the proportional-integral controller, which also prioritises the flux control loop, under various operating regions of the drive such as in the flux-weakening regime. Simulations show the performance expected with different control strategies which is then verified through experiments
Ensaio regional de linhagens de arroz irrigado do Programa de Melhoramento Genético da Embrapa no RS - safra 2008/09.
O Ensaio Regional de linhagens de arroz irrigado visa selecionar genótipos que apresentem alta adaptabilidade e estabilidade aos diversos ambientes em que são cultivadas e que expressem elevado rendimento de grãos, associado à características agronômicas, industriais e culinárias adequadas. Este experimento teve como objetivo avaliar linhagens do programa da Embrapa no Ensaio Regional de Rendimento
Desempenho de linhagens elites de arroz irrigado de ciclo precoce do Programa de Melhoramento Genético da Embrapa em ensaios VCU no RS - safra 2008/09.
O objetivo deste trabalho foi avaliar o desempenho em rendimento de grãos e características agronômicas de interesse das linhagens de ciclo precoce geradas pelo programa de melhoramento genético da Embrapa, em diferentes regiões orizícolas do Rio Grande do Sul, para verificar a possibilidade de indicação de novas cultivares
Desempenho de linhagens elite de arroz irrigado de ciclo médio do Programa de Melhoramento Genético da Embrapa em ensaios VCU no RS - safra 2008/09.
O objetivo deste trabalho foi avaliar o desempenho das linhagens geradas pelo Programa de Melhoramento Genético da Embrapa, em diferente regiões orizícolas do Rio Grande do Sul, visando possível lançamento de novas cultivares
Nutritional Factors Modulating Alu Methylation inan Italian Sample from The Mark-Age StudyIncluding Offspring of Healthy Nonagenarians
Alu hypomethylation promotes genomic instability and is associated with aging and
age-related diseases. Dietary factors affect global DNA methylation, leading to
changes in genomic stability and gene expression with an impact on longevity and
the risk of disease. This preliminary study aims to investigate the relationship
between nutritional factors, such as circulating trace elements, lipids and
antioxidants, and Alu methylation in elderly subjects and offspring of healthy
nonagenarians. Alu DNA methylation was analyzed in sixty RASIG (randomly
recruited age-stratified individuals from the general population) and thirty-two
GO (GeHA offspring) enrolled in Italy in the framework of the MARK-AGE project.
Factor analysis revealed a different clustering between Alu CpG1 and the other
CpG sites. RASIG over 65 years showed lower Alu CpG1 methylation than those of GO
subjects in the same age class. Moreover, Alu CpG1 methylation was associated
with fruit and whole-grain bread consumption, LDL2-Cholesterol and plasma copper.
The preserved Alu methylation status in GO, suggests Alu epigenetic changes as a
potential marker of aging. Our preliminary investigation shows that Alu
methylation may be affected by food rich in fibers and antioxidants, or
circulating LDL subfractions and plasma copper
Poly(ADP-ribose)glycohydrolase is an upstream regulator of Ca2+ fluxes in oxidative cell death
Oxidative DNA damage to cells activates poly(ADP-ribose)polymerase-1 (PARP-1) and the poly(ADP-ribose) formed is rapidly degraded to ADP-ribose by poly(ADP-ribose)glycohydrolase (PARG). Here we show that PARP-1 and PARG control extracellular Ca2+ fluxes through melastatin-like transient receptor potential 2 channels (TRPM2) in a cell death signaling pathway. TRPM2 activation accounts for essentially the entire Ca2+ influx into the cytosol, activating caspases and causing the translocation of apoptosis inducing factor (AIF) from the inner mitochondrial membrane to the nucleus followed by cell death. Abrogation of PARP-1 or PARG function disrupts these signals and reduces cell death. ADP-ribose-loading of cells induces Ca2+ fluxes in the absence of oxidative damage, suggesting that ADP-ribose is the key metabolite of the PARP-1/PARG system regulating TRPM2. We conclude that PARP-1/PARG control a cell death signal pathway that operates between five different cell compartments and communicates via three types of chemical messengers: a nucleotide, a cation, and proteins
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