Desenvolvimento de experiências de acionamento e controle do movimento angular de motores de indução trifásico

This paper aims to show practical and effectiveexperiencesfor lessons Industrial Automation Laboratory taught inundergraduate degreein ElectricalEngineering from the University Júlio MesquitaFilho - UNESP, Guaratinguetá. Experiments carriedsimulatecontrol and drive systems of electric three phase induction motors (MIT)widely usedinindustries. The experiments simulate a manufacturing environment where there isa need to control the activation and continuous operation ofelectricmotors. Seven experimentsthat simulatethe firing of electrical motors through a controlsystem, a driver along with asimulator loads coupled to the electric motor was developed. Experiments usinga Programmable Logic Controller (PLC) as acontroller,an inverter frequencyasdriver, and MagneticBrake, as simulatorengine loads . The experiments were divided accordingto the speed reference signal used fordrivingand operating the electric motor: digital and analog. The first five experiments performing the drive control and operation of the electric motor via digital signals. The sixth and seventh experiments using an analog signal as a reference speed for the electric motor

Controle de velocidade de um motor de indução trifásico usando técnicas de ajuste empírico para bancada de teste no laboratório de automação

This work aims to make the closed loop control of a three phase induction motor, through the integration of the following equipment: a frequency inverter, the actuator system; a programmable logic controller (PLC), the controller; an encoder, the velocity sensor, used as a feedback monitoring the control variable and the three-phase induction motor, the plant to be controlled. The control is performed using a Proportional - Integrative - Derivative (PID) approach. The PLC has a help instruction, which performs the auto adjustment of the controller, that instruction is used and confronted with other adjustment methods. There are several types of methods adjustments to the PID controllers, where the empirical methods are addressed in this work. The system is deployed at the Interface and Electro Electronic Control laboratory in the Universidade Estadual Paulista Júlio Mesquita Filho, Guaratinguetá, São Paulo, then, in the future, this work becomes an experiment to be conducted in the classroom, allowing undergraduate students to develop a greater affinity to the programs used by the PLC as well as studies of undergraduate and graduate works with the help of assembly made

Anestro pós-parto: luteólise prematura

The prolonged postpartum anoestrus in cows reduces the number of calves leading to a significant economic loss to producers. Suckling and nutrition are the factors of great importance to the extension of the post-partum period. Besides, the occurrence of short cycles within 30 to 40 days postpartum contributes to an increase in the parturition–conception interval. These cycles are related to development of a corpus luteum with reduced duration after the first ovulation (less than 12 days). It is known that the short persistence of the corpus luteum is caused by advance of the luteolytic mechanisms. However, there is a lack of consensus regarding the cause of this anticipation. There are two currently accepted hypotheses, one related to the lack of prior exposure to progesterone, and the other related to the low concentration of pre-ovulatory estrogen. Considering the decrease in the incidence of short cycles in cows treated with progesterone and estrogen, the main protocols of ovulation induction include combination of both hormones. Therefore, this study aimed at describing the post-partum anestrous in cows and the main predisposing factors, emphasizing the first postpartum ovulation, short cycle and, its respective causes and consequences

A indução da potencialização pós-ativação através dos saltos: pliométrico e vertical

The Post-Activation Potentiation (PAP) offers a proposal to optimize the production of strength and muscular power when performing exercises near maximum to actions previously assessed . The present study aims to show the activation process of postactivation potentiation (PAP) through vertical and plyometric jumps, and explain the user function of these movements. The ratio of post-activation potentiation resulting from plyometric and vertical jumps and explosive strength in the lower limbs aims to improve the potency and maximal strength, proven through studies and protocols detailed here. The results of this research come can be applied both for athletes and for individuals with experience in strength training and jumps (sports like volleyball, basketball and handball). The study was conducted through a literature review, conducted in scientific journals indexed in major databases (PubMed, ISI-Web of Science, SCIELO), books and academic papers (theses and dissertations)

Avaliação da indução de apoptose pela desintegrina recombinante DisBa-01 em macrófagos e células tumorais

O câncer é causado pela proliferação descontrolada de células, demonstrando uma capacidade coletiva de invasão e metástase. Durante a metástase, as células malignas precisam resistir a anoikis, uma apoptose celular gerada por falta de adesão. No câncer, as integrinas influenciam as células do hospedeiro associadas ao tumor bem como as próprias células tumorais, tendo o potencial de modular a progressão tumoral, a sobrevivência celular, a invasão e a metástase. A integrina αvβ3 é expressa em diversos tumores humanos, mas está em níveis muito reduzidos ou mesmo ausente nos tecidos normais, sendo considerada um alvo privilegiado na terapia anti-tumoral. Células derivadas da medula óssea, como o monócito/macrófago, também expressam esta integrina, ainda que em níveis reduzidos. A desintegrina recombinante DisBa-01 atua principalmente sobre as integrinas αvβ3 e αIIbβ3, e parece possuir a capacidade de inibir a adesão celular de linhagens possuindo a integrina αvβ3 à vitronectina. Sendo assim, observou-se a apoptose que pode ser gerada pela inibição da adesão celular ou pela própria presença da desintegrina, um antagonista de integrina que afeta a adesão celular, em linhagem neoplásica e em linhagem imortalizada de macrófagos, utilizando os métodos de marcação com anexina V e técnica de TUNEL, bem como a presença de células viáveis através da técnica de MTT. As linhagens celulares utilizadas nesse experimento foram expostas a desintegrina DisBa-01 por 24 horas para realização dos testes e as populações celulares aderentes e não aderentes foram analisadas separadamente. Verificou-se uma diminuição na viabilidade celular quando ocorre perda de adesão e na presença da proteína, mas foi observado um resultado não significativo para a ocorrência de apoptose. A desintegrina DisBa-01 ocasiona uma diminuição na viabilidade celular, entretanto parece não ser por apoptose gerando anoikis

Estudo experimental da indução magnética

This work will discuss how magnetic fields can be produced, either generated by magnets, natural, artificial, or even by an electric current going through a wire, as discovered by Oersted. Besides the theoretical content, experimental studies on magnetic induction and on the Laws of Faraday and Lenz will be performed. In the Magnetic Induction experiment, the electromotive force generated by varying the flow of the field B in a solenoid, depending on the variation of the current intensity and frequency associated with it will be measured; the experiment on the Laws of Faraday and Lenz the electromotive force produced by the relative movement of the magnet in relation to a coil. Thus, this study experimental verification of magnetic induction using solenoids and magnets; analysis of magnetic induction by Faraday's Law and Lenz's Law

Construindo desenvolvimento sustentável: contextualização dos mecanismos da gestão empresarial de recursos hídricos superficiais no estado de São Paulo

A escassez de água para a manutenção dos processos naturais ou para abastecimento humano e em empreendimentos seja em quantidade ou qualidade, corrobora a necessidade e a urgência de comprometimento efetivo de responsabilidade do ser humano com os recursos hídricos e com o ambiente. Falar em Gestão Ambiental (GA), entretanto, especialmente no Brasil, tornou-se lugar comum no discurso de diversos segmentos da sociedade, e em muitos casos desprovido de sentido efetivo. No meio empresarial, ações e discurso ambiental veiculados são reflexo da atuação de diferentes perfis de profissionais, com diferentes tipos de treinamento, e regidos por interesses que nem sempre remontam preocupação com o meio. A regulamentação sobre como devem ser exercida a atuação na área de ambiental, entretanto, bem como monitoramento institucional desta atuação, ainda se encontram em estágio de construção. Mas, a crescente pressão da demanda socioeconômica na iniciativa privada responde por crescente consumo de água e produção de águas residuárias. Para que o desenvolvimento atingido seja sustentável nestes empreendimentos é, portanto, urgente que haja disseminação de informação a gestores ambientais e a comunidade, disponibilizando ferramentas para um gerenciamento mais adequado – com entendimento da situação, de alternativas para amenizar impactos gerados, de como o empreendimento se insere neste cenário e com acompanhamento do desenvolvimento institucional. Assim, este trabalho tem como proposta a produção de material de referência na contextualização da situação dos mecanismos da gestão de recursos hídricos superficiais no estado de São Paulo para empreendimentos, dentro do foco do saneamento básico. Isso foi realizado através de revisão bibliográfica em livros e artigos científicos, teses acadêmicas, levantamento...(Resumo completo, clicar acesso eletrônico abaixo)

Avaliação da proliferação celular na próstata de gerbilos vasectomizados, após indução química pela injeção intraperitoneal do carcinógeno N-metil-N-nitrosuréia (MNU)

Prostate cancer is the second leading cause of cancer death in the country. Due to this factor, the interest of showing what relationship exists between vasectomy surgery and the incidence of prostate carcinoma has started. Some epidemiological studies showed an increased risk of prostate cancer in vasectomized men (Emard et al., 2001). On the other hand other authors have argued that there is no correlation (Patel et al., 2005) and there are those who said that vasectomy is linked to reduced risk of prostate cancer (Ross, 1983). Faced with an analysis of published works, such discussion remains today. The vasectomy, or deferentectomia, is a contraceptive male method, which is the section of the vas deferens of man by preventing the sperm from being expelled along with the seminal fluid during ejaculation, and is one of the most simple, economical, uncomplicated post- operative. This study aims to evaluate the process of cell proliferation and to evaluate immuno-histochemically the expression of specific markers of PCNA (Proliferating Cell Nuclear Antigen) and Ki-67, in the prostate of the gerbil after chemical induction by intraperitoneal injection of the carcinogen N-methyl -N-nitrosourea (MNU), because the regulation of the functional balance between cell proliferation and apoptosis is associated with hyperplasia and prostatic carcinoma. The experimental procedure was performed at the Laboratory of the Department of Anatomy, along with collecting the data for later analysis

Mecanismos envolvendo receptores opióides μ do núcleo parabraquial lateral no controle da ingestão de água e sódio

No sistema nervoso central (SNC), mecanismos excitatórios e inibitórios atuam para controlar a ingestão de água e sódio. Importantes mecanismos inibitórios da ingestão de água e sódio foram recentemente descobertos no núcleo parabraquial lateral (NPBL). Um papel importante do NPBL seria integrar as informações ascendentes da porção medial do núcleo do trato solitário (NTSm) e da área postrema (AP) que por sua vez poderiam influenciar a atividade das áreas prosencefálicas envolvidas no controle do balanço hidroeletrolítico, como núcleos específicos do hipotálamo e amígdala. Estudos prévios sugerem a presença de um importante mecanismo serotonérgico inibitório da ingestão de água e sódio no NPBL. Além do mecanismo serotonérgico também já foi demonstrado no NPBL a existência de um mecanismo colecistocinérgico que também exerce um papel inibitório sobre a ingestão de água e sódio. Em um estudo anterior em que se injetou um agonista e um antagonista inespecíficos de receptores opióides (β-endorfina e naloxona, respectivamente) no NPBL foi demonstrado que mecanismos opióides no NPBL podem modular o mecanismo inibitório da ingestão de água e sódio, porém não se sabia qual ou quais dos três subtipos de receptores opióides (μ, δ ou κ) estariam envolvidos nesse mecanismo... (Resumo completo, clicar acesso eletrônico abaixo)

Cálculo do tempo de permanência de um cilindro de laminação em um equipamento de aquecimento por indução durante um processo de têmpera

Induction heating is a process closely linked to the concepts of heat transfer. It also covers electromagnetic induction and effect of film. Many companies use this technology in their processes due to the high accuracy that can be obtained at temperatures induced. However the dominance of this technology is not common among Brazilian industries. This involves complex systems of equation and heat exchange in transient conduction, and convection and radiation losses. With this work we seek the ability to analyze which parameters influence over this process and the order of magnitude of time required for heating a cylindrical part

Comprimidos de HPMC contendo nimesulida: preparação, caracterização e estudo dos mecanismos que regem a liberação do fármaco

The pharmaceutical innovations, such as the use of polymers to control drug release, create possibilities for a better action of the drug in the body, which causes a a more effective therapeutic effect and a safer treatment for the patient. In this work, were prepared and characterized matrix tablets of hydroxypropylmethylcellulose (HPMC) containing nimesulide as model drug to evaluate the performance as a controlled release system. HPMC, a cellulose ester, is a hydrophilic polymer that undergoes swelling, i.e., absorbs water and forms a gel layer controlling drug release. The characterization of powders was performed by analysis of particle size and morphology, density, compressibility index determination, flow properties and determination of swelling profile. The tablets were evaluated according to their physical parameters of quality and to the in vitro release of nimesulide, as well as the analysis of the mechanisms of drug release by appropriate mathematical models. The set of results showed that the HPMC/Nimesulide mixture exhibited satisfactory physical characteristics (size, shape, density and flow). The release profile demonstrated an effective control upon drug release in enteric environment and presented more correlation with Korsmeyer-Peppas’ and Weibull’s mathematical models, indicating that the release of nimesulide occurs through the relaxation of the polymer chains

Efeitos de relevância versus repetição de estímulo lingüístico na indução da memória declarativa

In the LTP (Long-Term Potentiation) model of learning and memory formation, elaborated in the context of molecular neurobiology, the opening of NMDA (N-Metyl-D-Aspartate) channels to entry of calcium ions into the post-synaptic neuron depends on two excitatory events: the repeated activation of the post-synaptic neuron by only one pre-synaptic neuron (Alternative 1), or its concomitant activation by two or more pre-synaptic neurons (Alternative 2). With the purpose of testing these alternatives, in the context of Cognitive Psychology, we presented to 73 university students a sequence of slides, with the duration of 6 seconds each, containing sentences (one for each slide) considered as being relevant or irrelevant for the subjects. Relevant sentences (R1) were presented only one time, while irrelevant ones were divided in three groups: the first one with sentences presented only one time (I1), the second with sentences presented three times (I3) and the third with sentences presented five times (I5). We conjectured that relevant sentences presented only one time would mobilize two or more brain excitatory pathways (corresponding to Alternative 2 above), while repeated irrelevant sentences would progressively activate the same sensory pathway. After the presentation of the sentences, the subjects answered a written questionnaire with questions about each presented sentence. The results indicate a prevalence of correct answers to R1 over I1, I3 and I5, suggesting that the relevance factor has greater weight than repetition in the induction of declarative memories

Teoria do desenho de mecanismos: aplicações na teoria dos conflitos internacionais

O presente trabalho busca apresentar os conceitos principais referentes à Teoria do Desenho de Mecanismos e sua aplicação à Teoria dos Conflitos Internacionais, e como sua utilização pode solucionar alguns problemas referentes à metodologia mais utilizada na análise dos conflitos, baseada na Teoria dos Jogos tradicional. Através de uma análise game-free, estabelecem condições gerais para a resolução de conflitos entre países, sem a necessidade de estabelecer formas de jogo específicas. Desse modo, determinam-se resultados para qualquer equilíbrio de qualquer forma de jogo que envolva países em disputa. O trabalho segue apresentando a relação causal entre incerteza e incentivos para revelar de maneira desonesta informações privadas como causas fundamentais de guerra. Analisam-se separadamente as condições que levam à guerra em dois tipos de incerteza, constantemente discutidas na literatura de conflitos internacionais: incerteza em relação ao custo de guerra e em relação à força relativa. Os resultados são apresentados com a devida formulação matemática

Avaliação gastroprotetora da epicatequina e verificação de seus mecanismos de ação

The stomach is an exceptional organ, which functions are sterilize food ingested, form the primitive bolus, digest lipids and proteins, and to store food temporarily in the gastrointestinal tract. Its capacity of digesting food without digesting itself is amazing. This fact occurs due to innumerous protective substances adjacent to the gastric mucosa. When aggressive factors overwhelm the protective factors, a lesion in the gastric mucosa is formed. Lesions that reach the lamina propria are called gastric ulcers, which are classified macroscopically as openings on the gastric wall and; microscopically, as a gastric injury characterized with epithelial desquamation, mucosal hemorrhage, glandular damage and eosinophilic infiltration. The current therapy available is effective, although it causes collateral effects, therefore researching new drugs is necessary. This work aim to evaluate the gastroprotective effect of epicatechin against gastric lesions induced by absolute ethanol and non steroidal anti-inflammatory drugs which are the main causes of this disease currently, yet we aim to study the main mechanisms of action responsible for the gastroprotective effect. The results show that epicatechin has a significant macroscopic and microscopic gastroprotective effect against gastric injuries induced by ethanol and indomethacin, acting locally by augmenting gastric mucus secretion and it also acts via antioxidant system by holding total glutathione levels. Epicatechin’s gastroprotective mechanisms depend on the activation of sulfhydryl compounds and doesn’t depend on the NO-synthase enzyme

Indução de parto em bovinos: Princípios e aplicações

Currently, Brazil has one of the largest cattle herds worldwide. In order to keep that milk and meat were introduced reproductive biotechnologies such as artificial insemination, embryo transfer and in vitro fertilization. In certain situations the technique may have undesired effect, for example, the production of calve calves due to the very large increase in the gestation period when performed in vitro fertilization. To avoid this problem we perform the induction of labor in order to prevent the product is longer the womb. This induction can also be made in case of diseases that compromise the life of the mother, twin pregnancy an abnormal size calf. The administration of short acting steroids, prostaglandins, association of short acting steroids and prostaglandins and association of short acting steroids, prostaglandins and long-acting corticosteroids are some of the possibilities of induction