199 research outputs found
Projeto e Detalhamento de Hardware do Sistema Embarcado para Controle de Vôo de um Aerofólio Cabeado
TCC(graduação) - Universidade Federal de Santa Catarina. Centro Tecnológico. Engenharia de Controle e Automação.O UFSCKite é um grupo de pesquisa situado no Departamento de Automação e Sistemas da UFSC que se propõe a investigar e desenvolver tecnologias que aproveitem a energia eólica em elevadas altitudes para geração de energia elétrica. Dentro desta área, o grupo tem dirigido seu foco para o estudo de sistemas que utilizam aerofólios flexÃveis cabeados para alcançar estes objetivos. Atualmente, o UFSCKite possui um protótipo simples operacional, capaz de controlar a trajetória dos aerofólios em vôo, mas sem a capacidade de gerar energia elétrica. Um segundo protótipo capaz de realizar o controle do sistema com geração de energia elétrica está em fase de projeto. A primeira parte do trabalho aqui apresentado consiste na revisão da primeira versão da placa eletrônica embarcada do primeiro protótipo. Inicialmente, os componentes de hardware e a primeira versão da placa eletrônica embarcada do primeiro protótipo são descritos. Após isso, os problemas apresentados na primeira versão da placa eletrônica embarcada são analisados e a partir dessa análise uma segunda versão é proposta. Em seguida, os esquemáticos e o leiaute da segunda versão são apresentados. A segunda parte do trabalho aqui apresentado consiste no projeto da placa eletrônica embarcada da unidade de Vôo do segundo protótipo. Para a fundamentação deste projeto, um estudo é feito sobre o problema a ser resolvido. Primeiramente, os componentes de hardware do segundo protótipo são descritos. Em seguida, um projeto informacional do sistema embarcado é apresentado, contendo os seus requisitos, uma proposta de modelo funcional, uma tabela de opções de solução e algumas diretrizes a serem seguidas pelo projeto. Partindo deste projeto informacional, um projeto conceitual é proposto, apresentando de forma conceitual a arquitetura do sistema e as suas interfaces. Por fim, os elementos de hardware escolhidos para compor as interfaces são descritos com profundidade e os circuitos que compõem o projeto da eletrônica embarcada são apresentadosUFSCKite is a research group located in the Automation and Systems Department (DAS) of the Federal University of Santa Catarina (UFSC) that aims to investigate and develop technologies that take advantage of the wind power on high altitudes to generate electricity. The group focus have been the study of sistems that use pumping kites to achieve such goals. Currently, the UFSCKite has a simple operational prototype that controls the flight of a kite, but can’t generate electricity. A second prototype capable of both controlling the flight of the kite and generating electricity is being developed. This work consists on a review of the first version of the first prototype’s embedded electronics. First of all, the first prototype’s hardware components and embedded electronics are described. Next, the problems on the first version of the embedded electronics are analysed, and based on that analysis, a second version is proposed. After that, the second version’s electronic schematics and layouts are presented. In addition to that, the embedded electronic project of the second prototype‘s flight unit is proposed. A study is made based on the second prototype’s project. First, the hardware components are described. Then, an informational project of the embedded system is presented, containing a list of requirements, a functional model and some project guidelines. Based on this informational project, a conceptual project is proposed, presenting in a conceptual form the system’s architecture and it’s interfaces. Last, the hardware components of the interfaces are described and the embedded electronic’s circuits are presented
Semi-analytic galaxy formation in early dark energy cosmologies
We study the impact of early dark energy (EDE) cosmologies on galaxy
properties by coupling high-resolution numerical simulations with semi-analytic
modeling (SAM) of galaxy formation and evolution. EDE models are characterized
by a non-vanishing high-redshift contribution of dark energy, producing an
earlier growth of structures and a modification of large-scale structure
evolution. They can be viewed as typical representatives of non-standard dark
energy models in which only the expansion history is modified, and hence the
impact on galaxy formation is indirect. We show that in EDE cosmologies the
predicted space density of galaxies is enhanced at all scales with respect to
the standard LCDM scenario, and the corresponding cosmic star formation history
and stellar mass density is increased at high-redshift. We compare these
results with a set of theoretical predictions obtained with alternative SAMs
applied to our reference LCDM simulation, yielding a rough measure of the
systematic uncertainty of the models. We find that the modifications in galaxy
properties induced by EDE cosmologies are of the same order of magnitude as
intra-SAM variations for a standard LCDM realization (unless rather extreme EDE
models are considered), suggesting that is difficult to use such predictions
alone to disentangle between different cosmological scenarios. However, when
independent information on the underlying properties of host dark matter haloes
is included, the SAM predictions on galaxy bias may provide important clues on
the expansion history and the equation-of-state evolution.Comment: 7 pages; 4 figures, MNRAS submitte
A modified in-medium evolution equation with color coherence
QCD jets produced in heavy-ion collisions at LHC or RHIC energies partially evolve inside the produced hot and dense quark gluon plasma, offering unique opportunities to study QCD splitting processes in different backgrounds. Induced (modified) splittings are expected to be the most relevant mechanism driving the modifications of in-medium jets compared to vacuum jets for a wide sets of observables. Although color coherence among different emitters has been identified as an essential mechanism in studies of the QCD antenna radiation, it is usually neglected in the multi-gluon medium-induced cascade. This independent gluon emission approximation can be analytically proved to be valid in the limit of very large media, but corrections or modifications to it have not been computed before in the context of the evolution (or rate) equation describing the gluon cascade. We propose a modified evolution equation that includes corrections due to the interference of subsequent emitters. In order to do so, we first compute a modified splitting kernel following the usual procedure of factorizing it from the subsequent Brownian motion. The calculation is performed in the two-gluon configuration with no overlapping formation times, that is expected to provide the first correction to the completely independent pictureS
The effect of thermally pulsating asymptotic giant branch stars on the evolution of the rest-frame near-infrared galaxy luminosity function
We address the fundamental question of matching the rest-frame K-band
luminosity function (LF) of galaxies over the Hubble time using semi-analytic
models, after modification of the stellar population modelling. We include the
Maraston evolutionary synthesis models, that feature a higher contribution by
the Thermally Pulsating - Asymptotic Giant Branch (TP-AGB) stellar phase, into
three different semi-analytic models, namely the De Lucia and Blaizot version
of the Munich model, MORGANA and the Menci model. We leave all other input
physics and parameters unchanged. We find that the modification of the stellar
population emission can solve the mismatch between models and the observed
rest-frame K-band luminosity from the brightest galaxies derived from UKIDSS
data at high redshift. For all explored semi-analytic models this holds at the
redshifts - between 2 and 3 - where the discrepancy was recently pointed out.
The reason for the success is that at these cosmic epochs the model galaxies
have the right age (~1 Gyr) to contain a well-developed TP-AGB phase which
makes them redder without the need of changing their mass or age. At the same
time, the known overestimation of the faint end is enhanced in the K-band when
including the TP-AGB contribution. At lower redshifts (z<2) some of the
explored models deviate from the data. This is due to too short merging
timescales and inefficient 'radio-mode' AGN feedback. Our results show that a
strong evolution in mass predicted by hierarchical models is compatible with no
evolution on the bright-end of the K-band LF from z=3 to the local universe.
This means that, at high redshifts and contrary to what is commonly accepted,
K-band emission is not necessarily a good tracer of galaxy mass.Comment: 10 pages, 5 figures, accepted by MNRA
Biochemical responses, feeding and survival in the solitary bee Osmia bicornis following exposure to an insecticide and a fungicide alone and in combination
In agricultural ecosystems, bees are exposed to combinations of pesticides that may have been applied at different times. For example, bees visiting a flowering crop may be chronically exposed to low concentrations of systemic insecticides applied before bloom and then to a pulse of fungicide, considered safe for bees, applied during bloom. In this study, we simulate this scenario under laboratory conditions with females of the solitary bee, Osmia bicornis L. We studied the effects of chronic exposure to the neonicotinoid insecticide, Confidor® (imidacloprid) at a realistic concentration, and of a pulse (1 day) exposure of the fungicide Folicur® SE (tebuconazole) at field application rate. Syrup consumption, survival, and four biomarkers: acetylcholinesterase (AChE), carboxylesterase (CaE), glutathione S-transferase (GST), and alkaline phosphatase (ALP) were evaluated at two different time points. An integrated biological response (IBRv2) index was elaborated with the biomarker results. The fungicide pulse had no impact on survival but temporarily reduced syrup consumption and increased the IBRv2 index, indicating potential molecular alterations. The neonicotinoid significantly reduced syrup consumption, survival, and the neurological activity of the enzymes. The co-exposure neonicotinoid-fungicide did not increase toxicity at the tested concentrations. AChE proved to be an efficient biomarker for the detection of early effects for both the insecticide and the fungicide. Our results highlight the importance of assessing individual and sub-individual endpoints to better understand pesticide effects on bees
Biochemical responses, feeding and survival in the solitary bee Osmia bicornis following exposure to an insecticide and a fungicide alone and in combination
In agricultural ecosystems, bees are exposed to combinations of pesticides that may have been applied at different times. For example, bees visiting a flowering crop may be chronically exposed to low concentrations of systemic insecticides applied before bloom and then to a pulse of fungicide, considered safe for bees, applied during bloom. In this study, we simulate this scenario under laboratory conditions with females of the solitary bee, Osmia bicornis L. We studied the effects of chronic exposure to the neonicotinoid insecticide, Confidor (R) (imidacloprid) at a realistic concentration, and of a pulse (1 day) exposure of the fungicide Folicur (R) SE (tebuconazole) at field application rate. Syrup consumption, survival, and four biomarkers: acetylcholinesterase (AChE), carboxylesterase (CaE), glutathione S-transferase (GST), and alkaline phosphatase (ALP) were evaluated at two different time points. An integrated biological response (IBRv2) index was elaborated with the biomarker results. The fungicide pulse had no impact on survival but temporarily reduced syrup consumption and increased the IBRv2 index, indicating potential molecular alterations. The neonicotinoid significantly reduced syrup consumption, survival, and the neurological activity of the enzymes. The co-exposure neonicotinoid-fungicide did not increase toxicity at the tested concentrations. AChE proved to be an efficient biomarker for the detection of early effects for both the insecticide and the fungicide. Our results highlight the importance of assessing individual and sub-individual endpoints to better understand pesticide effects on bees
Ferricytochrome c Directly Oxidizes Aminoacetone to Methylglyoxal, a Catabolite Accumulated in Carbonyl Stress
Age-related diseases are associated with increased production of reactive oxygen and carbonyl species such as methylglyoxal. Aminoacetone, a putative threonine catabolite, is reportedly known to undergo metal-catalyzed oxidation to methylglyoxal, NH4+ ion, and H2O2 coupled with (i) permeabilization of rat liver mitochondria, and (ii) apoptosis of insulin-producing cells. Oxidation of aminoacetone to methylglyoxal is now shown to be accelerated by ferricytochrome c, a reaction initiated by one-electron reduction of ferricytochrome c by aminoacetone without amino acid modifications. the participation of O-2(center dot-) and HO center dot radical intermediates is demonstrated by the inhibitory effect of added superoxide dismutase and Electron Paramagnetic Resonance spin-trapping experiments with 5,5'-dimethyl-1-pyrroline-N-oxide. We hypothesize that two consecutive one-electron transfers from aminoacetone (E-0 values = -0.51 and -1.0 V) to ferricytochrome c (E-0 = 0.26 V) may lead to aminoacetone enoyl radical and, subsequently, imine aminoacetone, whose hydrolysis yields methylglyoxal and NH4+ ion. in the presence of oxygen, aminoacetone enoyl and O-2(center dot-) radicals propagate aminoacetone oxidation to methylglyoxal and H2O2. These data endorse the hypothesis that aminoacetone, putatively accumulated in diabetes, may directly reduce ferricyt c yielding methylglyoxal and free radicals, thereby triggering redox imbalance and adverse mitochondrial responses.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)INCT Processos Redox em Biomedicina (Brazil)Univ São Paulo, Dept Bioquim, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Bioquim & Biol Mol, São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, São Paulo, BrazilUniv São Paulo, Dept Fis & Informat, São Paulo, BrazilUniv Fed ABC, Ctr Ciencias Nat & Humanas, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Bioquim & Biol Mol, São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, São Paulo, BrazilWeb of Scienc
Intersetorialidade e potenciais conflitos de interesse entre governos e setor privado comercial no âmbito das ações de alimentação e nutrição para o enfrentamento de doenças crônicas não transmissÃveis | Intersectoriality and potential conflicts of interest between governments and private, commercial sector within the context of food and nutrition actions to deal with chronic non-communicable diseases
Neste artigo foram analisados os potenciais conflitos entre interesses governamentais e privados de caráter comercial em torno das ações de alimentação e nutrição (AN) no âmbito de propostas intersetoriais de enfrentamento das DCNT no Brasil. Para tal, foram identificados artigos acadêmicos e documentos institucionais publicados a partir de 2000 que abordassem as ações de AN em polÃticas de DCNT pautadas pela intersetorialidade. Foram priorizados elementos que contribuÃssem para a compreensão dos potenciais conflitos de interesse entre governos e o setor privado comercial no âmbito de estratégias intersetoriais de enfrentamento de DCNT. Concluiu-se que o princÃpio da intersetorialidade, desassociado de um processo polÃtico que problematize os critérios de eleição e as práticas institucionais dos setores que respondem pelo conjunto de ações que compõe as polÃticas governamentais, pode servir como facilitador do favorecimento de interesses comerciais. A participação no processo decisório de setores de interesse comercial cujas práticas ferem objetivos e princÃpios das polÃticas públicas, movidos pela expansão da demanda por seus produtos e pela concentração progressiva de poder, pode retardar, atenuar ou impedir ações efetivas na redução de DCNT. Esta possibilidade é particularmente relevante no âmbito de atribuições que são próprias aos entes Estatais, especialmente as estratégias regulatórias.
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This article analyzed the potential conflicts of interest between government and private commercial sectors in the area of food and nutrition (FN) activities within the context of intersectoral proposals for dealing with chronic non-communicable diseases (CNCD) in Brazil. To this end, academic articles and institutional documents published after 2000 were identified that addressed FN actions in CNCD policies guided by intersectoriality. Elements that contributed to understanding the potential conflicts of interest between governments and the private, commercial sector within the context of intersectoral strategies to deal with CNCD were prioritized. It was concluded that the principle of intersectoriality disassociated from a political process that complicates the eligibility criteria and institutional practices of the sectors responsible for the set of actions that comprise government policies may serve as facilitators for favoring commercial interests. Participation in the decision-making process of the sectors of commercial interest whose practices, driven by increased demand for their products and the progressive concentration of power, contradict the purposes and principles of public policy, may delay, reduce, or prevent effective actions to reduce CNCD. This possibility is particularly relevant in the context of attributions that are specific to government entities, especially regulatory strategies
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