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1.
Sensors (Basel) ; 22(17)2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36080889

RESUMEN

Several industrial pick-and-place applications, such as collaborative assembly lines, rely on visual tracking of the parts. Recurrent occlusions are caused by the manipulator motion decrease line productivity and can provoke failures. This work provides a complete solution for maintaining the occlusion-free line of sight between a variable-pose camera and the object to be picked by a 6R manipulator that is not wrist-partitioned. We consider potential occlusions by the manipulator as well as the operator working at the assembly station. An actuated camera detects the object goal (part to pick) and keeps track of the operator. The approach consists of using the complete set of solutions obtained from the derivation of the univariate polynomial equation solution to the inverse kinematics (IK). Compared to numerical iterative solving methods, our strategy grants us a set of joint positions (posture) for each root of the equation from which we extract the best (minimizing the risks of occlusion). Our analytical-based method, integrating collision and occlusion avoidance optimizations, can contribute to greatly enhancing the efficiency and safety of collaborative assembly workstations. We validate our approach with simulations as well as with physical deployments on commercial hardware.


Asunto(s)
Robótica , Fenómenos Biomecánicos , Movimiento (Física) , Robótica/métodos , Extremidad Superior , Muñeca
2.
Materials (Basel) ; 15(14)2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35888252

RESUMEN

Actuators using Shape Memory Alloy (SMA) springs could operate in different mechanical systems requiring geometric flexibility and high performance. The aim of the present study is to highlight the potential of these actuators, using their dimensional variations resulting from the phase transformations of NiTi springs (SMA) to make the movements of the system's mobile components reversible. This reversibility is due to thermal-induced martensitic transformation of NiTi springs. The transformation promotes the extended and retracted of the springs as the phase changing (martensite-austenite) creates movement in part of the system. Therefore, the phase transition temperatures of NiTi, evaluated by differential scanning calorimetry (DSC), are required to control the dimensional variation of the spring. The influence of the number of springs in the system, as well as how impacts on the reaction time were evaluated. The different numbers of springs (two, four, and six) and the interspaces between them made it possible to control the time and the final angle attained in the mobile part of the system. Mechanical resistance, maximum angle, and the system's reaction time using different NiTi springs highlight the role of the actuators. Fused Deposition Modelling (FDM)/Material Extrusion (MEX) or Selective Laser Sintering (SLS) was selected for shaping the composite matrix system. A new prototype was designed and developed to conduct tests that established the relationship between the recoverable deformation of the matrix suitable for the application as well as the number and distribution of the actuators.

3.
Zootaxa ; 4750(2): zootaxa.4750.2.14, 2020 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-32230483

RESUMEN

Horvathinia pelocoroides Montandon, 1911 was described as a new genus and species based on two specimens collected in Brazil, one from Minas Gerais deposited in the Naturhistoriska Riksmuseet (Stockholm) and the other from Rio Grande do Sul deposited in the Magyar Természettudományi Múzeum (Budapest) (Montandon 1911). Subsequently, nine additional species were described based on a single specimen each, collected at different localities in southern South America: H. doellojuradoi De Carlo, 1930; H. pelleranoi De Carlo, 1930; H. castilloi De Carlo, 1938; H. meyeri De Carlo, 1938; H. bollei De Carlo, 1958; H. lenti De Carlo, 1958; H. schubarti De Carlo, 1958; H. forsteri Lauck, 1958; and H. argemii Schnack, 1972 (Schnack Estévez 2005).


Asunto(s)
Hemípteros , Heterópteros , Animales , Insectos
5.
Zootaxa ; 4154(1): 96-100, 2016 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-27615828

RESUMEN

The genus Laccomimus Toledo & Michat, 2015 was recently erected for small drop-shape Dytiscidae beetles commonly found in Tropical South America associated with lentic waters. In the present paper a new species, Laccomimus xikrin sp. nov., is described and illustrated. New records from Brazil are presented for Laccomimus alvarengi Toledo & Michat, 2015 from Amazonas state, L. bordoni Toledo & Michat, 2015 from São Paulo state and L. variegatus Toledo & Michat, 2015 from Pará state.


Asunto(s)
Escarabajos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Escarabajos/anatomía & histología , Escarabajos/crecimiento & desarrollo , Femenino , Masculino , Tamaño de los Órganos
6.
Zootaxa ; 4111(1): 77-91, 2016 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-27394899

RESUMEN

The tribe Vatellini Sharp, 1882 is composed of 55 species divided in two genera. Even though a recent revision of the tribe was made, Vatellini of the new world are weakly explored with great gaps in the distributions of species. In Brazil the knowledge is based only on a few localities. In this work two new species are described and illustrated, Vatellus caissara sp. nov. and Vatellus yanomami sp. nov.; new records are given for Brazil: Vatellus maculosus Miller, 2005 in the state of Mato Grosso, Derovatellus lentus (Wehncke, 1876) in Amazonas, Pará and Rio de Janeiro, Vatellus lateralis (Sharp, 1882) in Alagoas, Ceará, Espírito Santo, Pará, Pernambuco and Rio Grande do Sul, Vatellus sahlbergi (Sharp, 1882) in Rio de Janeiro, and Vatellus tarsatus (Laporte, 1835) in Pará. A checklist with all species of Vatellini occurring in Brazil is provided and steps for identification of the new species are added in the key of Miller (2005).


Asunto(s)
Escarabajos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Lista de Verificación , Escarabajos/anatomía & histología , Escarabajos/crecimiento & desarrollo , Ecosistema , Femenino , Masculino , Tamaño de los Órganos
7.
J Insect Sci ; 14: 55, 2014 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-25373202

RESUMEN

Eight new species of Desmopachria Babington, 1841 are described and illustrated from Brazil: D. dicrophallica sp nov., D. disticta sp nov., D. grammosticta sp nov., D. grandinigra sp nov., D. itamontensis sp nov., D. leptophallica sp nov., D. stethothrix sp nov., and D. ukuki sp nov. The species D. amyae Miller, 2001, D. chei Miller, 1999, D. margarita Young, 1990, and D. volatidisca Miller, 2001 are recorded for the first time from Brazil. From species of the Desmopachria reported in Brazil, D. aldessa Young, 1980 has a new record from Pará state and D. fossulata Zimmermann, 1928, D. granoides Young, 1986, and D. laevis Sharp, 1882 have new records from Rio de Janeiro State. A checklist of all Desmopachria recorded from Brazil is presented with notes about some of the localities.


Asunto(s)
Escarabajos/anatomía & histología , Escarabajos/clasificación , Animales , Brasil , Escarabajos/genética , Femenino , Masculino , Especificidad de la Especie
8.
Artículo en Inglés | MEDLINE | ID: mdl-22225415

RESUMEN

This paper presents a method for prediction of forces and displacements in the expansion screw of a modified mandibular Schwarz appliance and the contact pressure distributions on the mucosa during malocclusions treatment. A 3D finite element biomechanical model of the complete mandible-mucosa-apparatus set was built using computerised tomographic images of a patient's mandible and constructive solid geometry by computer software. An iterative procedure was developed to handle a boundary condition that takes into account the mandibular asymmetries. The results showed asymmetries in the contact pressure distributions that indicated with precision the patient's malocclusion diagnosis. In vivo measurements of contact pressure using piezoelectric sensors agreed with the computational results. It was shown that the left and right ends of the expansion screw move differently with respect to the patient mandible, even though the expansion screw has an opening mechanism to ensure equal stretching at both ends. The contact pressures between the apparatus and the mucosa vary linearly with applied forces, which can simplify the analysis of the biomechanical behaviour of the expander mandible apparatus. The biomechanical modelling proposed in this paper can be a useful tool to improve malocclusions treatment, safely avoiding the use of forces acting on live structures beyond the biological tolerance, which could result in traumatic effects.


Asunto(s)
Maloclusión/terapia , Mandíbula/diagnóstico por imagen , Mucosa Bucal/fisiología , Aparatos Ortodóncicos , Fenómenos Biomecánicos , Simulación por Computador , Análisis de Elementos Finitos , Humanos , Presión , Programas Informáticos , Tomografía Computarizada por Rayos X
9.
J Investig Med ; 58(1): 32-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19820407

RESUMEN

BACKGROUND: The bladder's regulatory function is influenced by central serotonergic modulation. T102C polymorphism of the serotonin 2A (5-HT(2A)) receptor gene is associated with urinary incontinence (UI) that has been reported by older community dwellers. We analyzed the association between 5-HT(2A) receptor gene polymorphism and urodynamic tests for UI in older women. METHODS: A case-control study was performed with 68 older women submitted to urodynamic evaluation and 162 older women without urinary problems (self-reported), all community dwellers enrolled in the Gravataí-GENESIS Project, Brazil. Clinical interviews, complete urodynamic evaluation following the International Continence Society Report on Good Urodynamic Practice (case group), and molecular analyses were performed (case and control groups). Serotonin 2A receptor gene genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism using the restriction enzyme HpaII. We excluded patients with diabetes mellitus, neurologic damage, and diuretic intake. RESULTS: The subjects' mean (SD) age was 68.1 (6.5) years (range, 60-92 years). We found an association between the TT genotype versus CC + CT genotypes and UI (P = 0.013; odds ratio, 2.69; 95% confidence interval, 1.37-5.29) and, in addition, an association with urgency UI, maximal cystometric capacity (TT, 349 mL; CC + CT, 429.5 mL [P = 0.047]), detrusor pressure at maximum cystometric capacity (TT, 11 cm H(2)O; CC + CT, 6.75 cm H(2)O [P = 0.032]), and detrusor compliance (TT, 34 mL/cm H(2)O; CC + CT, 61.25 mL/cm H(2)O [P = 0.006]). CONCLUSIONS: We confirmed our previous findings of a genetic influence of the TT genotype on UI involving the serotonergic pathway among older women. Further investigations including 5-HT(2A) expression in the bladder, pelvic floor, and striated sphincter muscle must be performed.


Asunto(s)
Polimorfismo Genético , Incontinencia Urinaria/genética , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Receptor de Serotonina 5-HT2A/genética , Incontinencia Urinaria/fisiopatología , Urodinámica
10.
Rev. AMRIGS ; 52(4): 315-316, out.-dez. 2008. ilus
Artículo en Portugués | LILACS | ID: biblio-848863

RESUMEN

Tendo como tema o assunto abordado no primeiro artigo publicado pela Revista da AMRIGS, comenta-se a evolução havida na terapêutica clínica de uma situação bastante comum na prática do internista e do cardiologista e presta-se homenagem aos cinqüenta anos desta publicação e ao insigne professor Rubens Maciel (1913-2004) (AU)


Focusing on the theme discussed in the first article published by the AMRIGS journal, this is an account of the progress made in the clinical therapeutics of a very common situation in the practice of internists and cardiologists, as well as a tribute both to the 50 year anniversary of this journal and to the honorable Professor Rubens Maciel (1913 ­ 2004) (AU)


Asunto(s)
Humanos , Cardiología/historia , Insuficiencia Cardíaca/terapia , Publicaciones Periódicas como Asunto/historia , Insuficiencia Cardíaca/diagnóstico , Historia de la Medicina
11.
Acta méd. (Porto Alegre) ; 29: 150-156, 2008.
Artículo en Portugués | LILACS | ID: lil-510236

RESUMEN

Definir com clareza as repercusões oftalmológicas das doenças auto-imunes é muito importante para o médico, qual for sua especialidade. Estando diante de uma doença auto imune o médico tem obrigação de, para decorrente e saber em que casos ela pode comprometer a visão e que casos devem ser encaminhados ao oftalmologista. Artrite Reumatóide pode causar desde ceratoconjutivite seca até episclerite. Na artrite Reumatóide Juvenula criança deve ser acompanhada por um médico oftalmologista. Na Artrite de Células Gigantes um reconhecimento precoce do do acontecimento ocular pode evitar a perda da visão.


Asunto(s)
Enfermedades Autoinmunes
12.
RGO (Porto Alegre) ; 51(1): 41-43, jan.-mar. 2003. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-365825

RESUMEN

As fissuras e defeitos do lóbulo da orelha, embora pequenos no tamanho, acarretam grande desconforto e constrangimento. A cirurgia corretiva é simples e pode ser feita em ambiente ambulatorial. Neste artigo os autores apresentam um caso clínico, descrevendo a técnica utilizada.


Asunto(s)
Humanos , Femenino , Adolescente , Cirugía Plástica/métodos
13.
In. Toledo, Luiz Sérgio; Pinto, Ewaldo Souza. Annals of the International Symposium Recent Advances in Plastic Surgery. s.l, RAPS International Corporation, 1990. p.406-20, ilus.
Monografía en Inglés | LILACS | ID: lil-130507

RESUMEN

The author proposes using intercostal nerve block in cases of extremely large breasts, in order to offer mor safety conditions to the patients, fewer complications, shorter hospitalization time and lower costs. In a variation of the BOZOLA"s tecnique, a ressection of a large mass of breast tissues was made without any modification of the resulting "L" shaped scar


Asunto(s)
Humanos , Femenino , Adolescente , Adulto , Hipertrofia/cirugía , Mamoplastia , Bloqueo Nervioso , Mama/patología
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