Dynamics of Serial Manipulators using Dual Quaternion Algebra

This paper presents two approaches to obtain the dynamical equations of serial manipulators using dual quaternion algebra. The first one is based on the recursive Newton-Euler formulation and uses twists and wrenches instead of 3D vectors, which simplifies the classic procedure by removing the necessity of exhaustive geometrical analyses since wrenches and twists are propagated through high-level algebraic operations. Furthermore, the proposed formulation works for arbitrary types of joints and does not impose any particular convention for the propagation of twists. The second approach, based on Gauss's Principle of Least Constraint (GPLC), takes into account elements of the dual quaternion algebra and provides a linear relationship between twists derivatives and joint accelerations, which can be particularly useful in robot control. Differently from other approaches based on the GPLC, which have representational singularities or require constraints, our method does not have those drawbacks. We present a thorough methodology to obtain the computational cost of both algorithms and compared them with their classic counterparts. Although our current formulations are more computationally expensive, they are more general than their counterparts in the state of the art. Simulation results showed that both methods are as accurate as the classic recursive Newton-Euler algorithm.Comment: Submitted for publication (currently under review

Clinical significance of EGFR, Her-2 and EGF in oral squamous cell carcinoma: a case control study

<p>Abstract</p> <p>Background</p> <p>The erbB receptors and their ligands are involved in the pathogenesis and progression of oral squamous cell carcinoma (OSCC). Although EGFR and Her-2 are frequently overexpressed in OSCC, few studies evaluated these proteins in saliva and their association with the tumor, which may represent potential usefulness in a clinical setting.</p> <p>Methods</p> <p>The levels of EGFR, Her-2, and EGF were evaluated in saliva of 46 patients with OSCC before and after the surgical removal of the lesion, as well as in matched healthy controls. The relationship of salivary levels and EGFR and Her-2 immunoexpression in tumor samples with clinicopathological features was analyzed.</p> <p>Results</p> <p>EGFR and Her-2 salivary levels did not show difference between to pre-surgery and control groups, however, both demonstrated an increase after surgical removal of the tumor. No association was detectable among receptor salivary levels, tissue expression and clinicopathological features. EGF levels in pre-surgery group were significantly lower when compared to the control group.</p> <p>Conclusions</p> <p>EGFR and Her-2 were not considered to be valuable salivary tumor markers in OSCC, however, lower levels of EGF in saliva may suggest a higher susceptibility for OSCC development.</p

Perfil Ictiofaunístico de duas Lagoas no Rio Paraná, Região do Parque Nacional de Ilha Grande - PR

O Rio Paraná é o décimo maior do mundo em descarga e nele se encontra a região do Parque Nacional de Ilha Grande, que é formada por um conjunto de ilhas, lagoas e várzeas periodicamente alagadas, sendo estas de extrema importância para os peixes, servindo de refúgio contra predação, berçário natural e áreas de alimentação para muitas espécies de peixes. Este artigo apresenta um levantamento icitiofaunístico nas lagoas Saraiva e São João, situadas no Parque Nacional de Ilha Grande, com enfoque nas variações espaço-temporais, na composição específica e estrutura etária das assembléias de peixes, sendo que estes foram amostrados em coletas trimestrais, utilizando-se redes de espera de diferentes malhagens. Em termos de número de indivíduos capturados e proporção, tem-se 54% das espécies pertencentes a ordem Characiformes, 42% a Siruliformes, 3% a Perciformes. Rajiformes e Gymnotiformes contribuíram com menos de 1,5% do total das capturas. Na lagoa Saraiva foram capturadas 34 espécies pertencentes a cinco ordens e 17 famílias, destacando-se numericamente Loricariichthys platymetopon, Raphiodon vulpinus, Serrasalmus marginatus e Plagioscion squamosissimus. As maiores contribuições em peso foram proporcionadas por R. vulpinus, Potanotrygon motoro, P. squamosissimus e S. marginatus. Na lagoa São João ocorreram 46 espécies pertencentes a cinco ordens e 17 famílias, destacando-se em número L. platymetopon, Acestrohynchus lacustris, Serrasalmus spilopleura e S. marginatus. Em peso, Prochilodus lineatus, A. lacustris, L. platymetopon e Serrasalmus spilopleura foram as mais representativas. Destaca-se que a maioria das espécies registradas em ambas as lagoas são típicas de ambientes lênticos, utilizando esses locais para seu desenvolvimento e crescimento

PEDOT:PSS-coated polybenzimidazole electroconductive nanofibers for biomedical applications

Bioelectricity drives several processes in the human body. The development of new materials that can deliver electrical stimuli is gaining increasing attention in the field of tissue engineering. In this work, novel, highly electrically conductive nanofibers made of poly [2,20 - m-(phenylene)-5,50 -bibenzimidazole] (PBI) have been manufactured by electrospinning and then coated with cross-linked poly (3,4-ethylenedioxythiophene) doped with poly (styrene sulfonic acid) (PEDOT:PSS) by spin coating or dip coating. These scaffolds have been characterized by scanning electron microscopy (SEM) imaging and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. The electrical conductivity was measured by the four-probe method at values of 28.3 S·m−1 for spin coated fibers and 147 S·m−1 for dip coated samples, which correspond, respectively, to an increase of about 105 and 106 times in relation to the electrical conductivity of PBI fibers. Human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) cultured on the produced scaffolds for one week showed high viability, typical morphology and proliferative capacity, as demonstrated by calcein fluorescence staining, 40 ,6-diamidino-2-phenylindole (DAPI)/Phalloidin staining and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay. Therefore, all fiber samples demonstrated biocompatibility. Overall, our findings highlight the great potential of PEDOT:PSS-coated PBI electrospun scaffolds for a wide variety of biomedical applications, including their use as reliable in vitro models to study pathologies and the development of strategies for the regeneration of electroactive tissues or in the design of new electrodes for in vivo electrical stimulation protocols.info:eu-repo/semantics/publishedVersio

Dataset after seven years simulating hybrid energy systems with Homer Legacy

Homer Legacy software is a well-known software for simulation of small hybrid systems that can be used for both design and research. This dataset is a set of files generated by Homer Legacy bringing the simulation results of hybrid energy systems over the last seven years, as a consequence of the research work led by Dr. Alexandre Beluco, Federal University of Rio Grande do Sul, in southern Brazil. The data correspond to twelve papers published in the last seven years. Two of them describe hydro PV hybrid systems with photovoltaic panels operating on the water surface of reservoirs. One of these twelve papers suggests the modeling of hydropower plants with reservoirs and the other the modeling of pumped hydro storage, and a third still uses these models in a place that could receive both the two types of hydroelectric power plant. The other simulated hybrid systems include wind turbines, diesel generators, batteries, among other components. This data article describes the files that integrate this dataset and the papers that have been published presenting the hybrid systems under study and discussing the results. The files that make up this dataset are available on Mendeley Data repository at https://doi.org/10.17632/ybxsttf2by.2

ANÁLISE NÃO-LINEAR DA CONTRIBUIÇÃO DE ARMADURAS COMPLEMENTARES NA RESISTÊNCIA AO ARRANCAMENTO DE PINOS EMBUTIDOS EM CONCRETO

Conectores de aço com cabeça são empregados na ligação entre estruturas mistas de aço e concreto e em estruturas pré-moldadas. Quando solicitados à tração, a resistência ao arrancamento é fator determinante no projeto e o modo de ruptura pela formação do cone de concreto pode ser frágil. Uma das formas de aumentar a resistência dessa ligação é utilizar armaduras complementares. Para avaliar a influência da armadura complementar na resistência ao arrancamento, foram elaborados 6 modelos computacionais não-lineares em EPD no programa MIDAS FEA, com base em uma série de ensaios experimentais de conectores embutidos em vigotas de concreto armado. A modelagem buscou avaliar a influência do diâmetro da armadura complementar, do número de pernas interceptando o cone de concreto e da distância do conector até da armadura complementar. Foi realizado um estudo paramétrico para ajustar as propriedades do concreto, variando a resistência à tração, módulo de elasticidade e a energia de fratura. A análise computacional realizada apresenta tabelas com carga de ruptura, gráficos de carga x deslocamento, carga x deformação na armadura longitudinal e carga x deformação na armadura transversal, de forma geral se apresentando em boa concordância com os resultados experimentais

Bladder sensory desensitization decreases urinary urgency

Research articl

Distribution of common peroneal nerve in equine fetuses and anatomical description of sites for anesthetic block

Analisou-se a distribuição do nervo fibular comum em 30 fetos de equinos, sem raça definida, provenientes do acervo do Laboratório de Anatomia Animal da Faculdade de Medicina Veterinária da Universidade Federal de Uberlândia, que foram injetados e conservados em solução aquosa de formaldeído a 10%. Contatou-se que o referido nervo deriva do isquiático, divide-se em nervos fibulares superficial e profundo, distribuindo-se para os músculos extensores lateral e longo do dedo, fibular terceiro e tibial cranial. Traçando-se uma linha imaginária na região médio-lateral da tuberosidade do osso tíbia, o nervo fibular comum pode ser bloqueado em sua parte proximal, no terço caudal, entre o tendão de inserção do músculo bíceps femoral e a face lateral do músculo gastrocnêmio lateral (terço médio); e o nervo fibular profundo, na parte proximal da tíbia, crânio-distalmente ao fibular comum. O bloqueio do nervo fibular superficial pode ser realizado em duas regiões da tíbia: na proximal, considerando-se a linha imaginária, distalmente ao ponto citado para o fibular comum e caudalmente ao descrito para o fibular profundo; e na distal, na face lateral da articulação tíbio-társica, entre os tendões de inserção dos músculos extensores lateral e longo do dedo.Iglesias L.P., Silva F.O.C., Vasconcelos B.G., Ribeiro L.A., Hodniki N.F., Gomes L.R., Miglino M.A. & Melo A.P.F. 2012. [Distribution of common peroneal nerve in equine fetuses and anatomical description of sites for anesthetic block.] Distribuicao do nervo fibular comum em fetos de equinos e descricao anatomica de pontos para bloqueio anestesico. Pesquisa Veterinaria Brasileira 32(7):672-676. Departamento de Anatomia Animal, Faculdade de Medicina Veterinaria, Universidade Federal de Uberlandia, Rua Ceara s/n, Bloco 2D, Uberlandia, MG 38400-902, Brazil. E-mail: [email protected] The distribution of the nervus fibularis communis was analyzed in 30 equine fetuses, mongrel, from the collection of the Animal Anatomy Laboratory at the School of Veterinary Medicine of Universidade Federal de Uberlandia, which were injected and stored in an aqueous solution of 10% formaldehyde. It was found that this nerve emerges from the ischiadicus, divides itself into nervus fibularis profundus and nervus fibularis super ficialis distributing to the musculi extensor digitorum lateralis, extensor digitorum longus, fibularis tertius, and tibialis cranialis. Drawing an imaginary line in the medial-lateral region of the tuberositatis tibia, the nervus fibularis communis may be blocked in its proximal portion, in the caudal third, between the tendon of insertion of the biceps femoris and the lateral side of the musculus gastrocnemius (medium third); and the nervus fibularis profundus may be blocked in the proximal tibia, cranio-distally to the nervus fibularis communis. The block of nervus fibularis profundus may be performed in two regions of the tibia: proximal, considering the imaginary line, distal to the site referred to the nervus fibularis communis, and caudal to that described for the nervus fibularis profundus; and distal, on the lateral side of the tibiotarsal joint, between the tendons of insertion of the musculi extensor digitorum lateralis and extensor digitorum longus