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Objectives We intend to describe a case of McCune-Albright Syndrome (MAS), a rare disease characterized by fibrous dysplasia (FD), cutaneous hyperpigmentation and hyperfunctioning endocrinopathies (HFE). Case presentation We report the case of a 13-year-old male child who presented with a café-au-lait macule in the lumbosacral region and disabling polyostotic FD, requiring several surgical interventions and bisphosphonates from the age of 3 years (Y) + 9 months (M) due to persistent and severe pain. Hyperthyroidism (HT) became apparent at 5 Y + 1 M with a T3/T4 ratio greater than 20. Treatment with anti-thyroid drugs (ATD) was carried out for 7 Y and there was a progressive improvement in pain complaints 8 M after starting ATD, allowing treatment with pamidronate to be discontinued. Total thyroidectomy was performed at 12 Y + 5 M. Conclusions This is a case of MAS-associated HT that reflects the deleterious effect of thyroid hormone excess on FD, reinforcing the need of having a low threshold for suspicion of HFE that may arise.

Introduction: The first Portuguese COVID-19-related state of emergency (SE) extended between March and May 2020. The relevance of achieving the glycemic target for the person with type 1 Diabetes Mellitus (T1DM) is deepened in these circumstances, given the forced changes in daily routine. Objective: To determine the influence of work activity (WA) on glycemic control (GC) of adults with T1DM after the first SE. Material and methods: A retrospective cohort study was designed to enroll adults with ≥2 years from T1DM diagnosis. Cases of pregnancy/hospitalizations in 2019/2020, factors that affect interpretation of glycated hemoglobin (HbA1c) and/or SARS-CoV-2 infections were excluded. The participants were stratified into groups of WA after the SE: g1 (telework/lay-off/students), g2 (retired/unemployed) and g3 (WA without lockdown). HbA1c were obtained from 4 periods: t3 (4/1-6/1/2020); t4 (7/1-9/1/2020); t1 and t2 (homologous periods of 2019). Differences in HbA1c were calculated in both years and compared to each other in the same group and between groups in the same year. Hypoglycemia and insulin regimens (insulin pump and multiple injections daily) were analyzed in intragroup (t3 vs. t4) and intergroup (t3 and t4) comparisons. Results: Two hundred and seven participants were included [106 (51.2%) men; median age of 35 (25;47) years]: 144 (69.6%) in g1, 44 (21.3%) in g2 and 19 (9.2%) in g3. HbA1c increased significantly between t4 and t3 (vs. t2 and t1) in g1 (p=0.001), but not in g2 (p=0.077) and g3 (p=0.744). In 2020, HbA1c raised significantly in the analysis "g1 vs. g3" (p=0.004), but not in "g1 vs. g2" (p=0.213) and "g2 vs. g3" (p=0.083). No differences were reported in 2019, along with all the comparisons involving hypoglycemia and insulin regimens. Conclusions: This study found an overall worsening of GC in participants who returned to higher levels of activity after a total lockdown. This is probably explained by the time spent on T1DM self-care during the lockdown. Disclosure D. Ramalho: None. S. Correia: None. L. Almeida: None. H. Alves: None. G. Rocha: None. M. Ferreira: None. M. J. Oliveira: None.

Este artigo tem como objetivo a modelagem matemática e o estudo de estabilidade de um circuito de estimulação elétrica em corrente pulsada. Assim, o trabalho apresenta um circuito de estimulação elétrica o qual é representado matematicamente por um modelo não linear. Ademais, a modelagem matemática é baseada em representação por espaço de estados visando representar o modelo como um sistema chaveado descritor afim. Logo, o estudo de estabilidade do sistema é desenvolvido com base em uma função quadrática de Lyapunov e Desigualdades Matriciais Lineares (LMIs), que quando factíveis, demonstram que o sistema pode ser controlado por uma estratégia de chaveamento adequada. Os resultados de simulação apresentados evidenciam que o procedimento de projeto propostotem um desempenho adequado, sendo que resultados experimentais validam a modelagemproposta no projeto. Palavras-chave: Circuito eletroestimulador. Modelagem. Controle não linear. Stability of key systems related descriptors with application in an electrostimulator circuit Abstract This article aims the mathematical modeling and a stability study of a pulsed current electrical stimulation circuit. Thus, the paper presents an electrical stimulation circuit which is mathematically represented by a non-linear model. Furthermore, the mathematical modeling is based on state space representation in order to represent the model as an affine descriptor switched system.. Therefore, the stability study of the system is developed based on a quadratic Lyapunov function and Linear Matrix Inequalities (LMIs), which when feasible, demonstrate that the system can be controlled by an adequate switching strategy. The simulation results presented show that the proposed design procedurehas an adequate performance, and experimental results validate the modeling proposed in the project. Keywords: Electrostimulator circuit. Modeling. Non-linear control

SUMMARY Pseudohypoparathyroidism comprehends an assorted group of genetically rare disorders that share end-organ resistance to parathyroid hormone. Genetic and epigenetic modifications on guanine nucleotide-binding protein alpha-stimulating gene locus are the most common underlying mechanisms associated with pseudohypoparathyroidism. Biochemical and molecular analysis stratify pseudohypoparathyroidism into types 1A, 1B, 1C, and 2. We describe an unusual case of sporadic pseudohypoparathyroidism type 1B. A 34-year-old Caucasian woman was admitted to the emergency department, with persistent asthenia, limb paresthesias, and tactile hyposensitivity. Her physical examination, previous personal and family histories were unsuspicious, except for mild, intermittent and self-limited complaints of paresthesia during her two pregnancies, but no detailed workup was done. No typical features of Albright hereditary osteodystrophy were observed. The initial laboratory investigation showed elevated parathyroid hormone level (311.2 pg/mL), hypocalcemia (albumin-corrected serum calcium 4.3 mg/dL), hypocalciuria, hyperphosphatemia, hypophosphaturia, and vitamin D deficiency. Combined calcium, vitamin D, and magnesium supplementation was commenced, with symptomatic and analytical improvement. Albeit resolution of vitamin D deficiency, the patient relapsed with mild and intermittent lower limb paresthesias. Pseudohypoparathyroidism was confirmed by molecular identification of the 3-kb STX16 deletion. The treatment was readjusted, and one year later, symptomatic remission was attained. Clinical and biochemical features, and their respective course, along with lack of distinctive features of Albright hereditary osteodystrophy pointed to pseudohypoparathyroidism type 1B. A careful follow-up is needed to avoid complications and recurrence. Once correction of hypocalcemia and hyperphosphatemia is achieved, with no reported complications and recurrence, a good prognosis is anticipated, comparable to the general population.

SUMMARY Pseudohypoparathyroidism comprehends an assorted group of genetically rare disorders that share end-organ resistance to parathyroid hormone. Genetic and epigenetic modifications on guanine nucleotide-binding protein alpha-stimulating gene locus are the most common underlying mechanisms associated with pseudohypoparathyroidism. Biochemical and molecular analysis stratify pseudohypoparathyroidism into types 1A, 1B, 1C, and 2. We describe an unusual case of sporadic pseudohypoparathyroidism type 1B. A 34-year-old Caucasian woman was admitted to the emergency department, with persistent asthenia, limb paresthesias, and tactile hyposensitivity. Her physical examination, previous personal and family histories were unsuspicious, except for mild, intermittent and self-limited complaints of paresthesia during her two pregnancies, but no detailed workup was done. No typical features of Albright hereditary osteodystrophy were observed. The initial laboratory investigation showed elevated parathyroid hormone level (311.2 pg/mL), hypocalcemia (albumin-corrected serum calcium 4.3 mg/dL), hypocalciuria, hyperphosphatemia, hypophosphaturia, and vitamin D deficiency. Combined calcium, vitamin D, and magnesium supplementation was commenced, with symptomatic and analytical improvement. Albeit resolution of vitamin D deficiency, the patient relapsed with mild and intermittent lower limb paresthesias. Pseudohypoparathyroidism was confirmed by molecular identification of the 3-kb STX16 deletion. The treatment was readjusted, and one year later, symptomatic remission was attained. Clinical and biochemical features, and their respective course, along with lack of distinctive features of Albright hereditary osteodystrophy pointed to pseudohypoparathyroidism type 1B. A careful follow-up is needed to avoid complications and recurrence. Once correction of hypocalcemia and hyperphosphatemia is achieved, with no reported complications and recurrence, a good prognosis is anticipated, comparable to the general population.

Um projeto de controle H1 chaveado para uma classe de sistemas n˜ao lineares incertos descritos por modelos fuzzy Takagi-Sugeno ´e apresentado neste trabalho. A metodologia apresentada baseia-se na constru¸c˜ao de um vetor de estado expandido, formado pelo vetor de estado e pelo sinal de controle. Al´em disso, a lei de controle chaveada elimina a necessidade de usar as fun¸c˜oes de pertinˆencia na sua implementa¸c˜ao e as condi¸c˜oes de projeto garantem apermanˆencia das trajet´orias dos estados e do sinal de controle dentro de uma regi˜ao de opera¸c˜ao do sistema. Por fim, o esquema de controle elimina a possibilidade de uma descontinuidade no sinal de controle.

This paper addresses the local stabilization problem and the computation of invariant subsets of the domain of attraction for uncertain nonlinear discrete-time systems. The proposed procedures use Takagi-Sugeno (T-S) fuzzy models that have uncertain membership functions and known local linear models. Based on a non-quadratic Lyapunov function, the proposed method uses a switched control law and the design conditions are given in terms of a optimization problem subject to Linear Matrix Inequalities (LMIs) constraints. The procedure provides a new and effective way to enlarge the estimation of the domain of attraction (DOA). Finally, a numerical example illustrates the effectiveness of the proposed method and compares it with procedures found in the literature.

This paper addresses the issue of robust H∞ control for a class of continuous-time uncertain switched linear systems. A set of state-feedback gains and two switching rules are designed to render the closed-loop system globally stable and assuring a guaranteed H∞ cost. The corresponding parameters of the controller are obtained by solving an optimization problem given in terms of Linear Matrix Inequalities (LMIs). Finally, an example using an active suspension system illustrates the effectiveness of the proposed approach.

This manuscript presents a switched control design for robust control of a class of uncertain nonlinear systems. In particular, it is considered a class of nonlinear systems whose dynamics are described by polynomial functions, that depend on the state vector of the system, with uncertain parameters. The design procedure can be represented in terms of sum of squares. The proposed switched control procedure uses a switching law to select at each instant of time a state-feedback polynomial gain, which belongs to a set of gains obtained from the proposed design procedure. The aim of the switching law is to choose a state-feedback polynomial gain that minimizes the time derivative of a polynomial Lyapunov function. A numerical example, using a chaotic Lorenz system with parametric uncertainties, illustrates the validity of the proposed approach.

RESUMO: As cardiopatias congénitas (CC) afetam aproximadamente 1% dos recémnascidos e são responsáveis pela maior proporção de mortalidade infantil nos países desenvolvidos. A coarctação da aorta (CoA), a 6ª CC mais frequente, consiste numa estenose da aorta descendente proximal. Se não for tratada, tem uma história natural desfavorável. A cirurgia, dilatação com balão e a implantação de stent são atualmente técnicas que podem atingir o objetivo de uma remoção eficaz e duradoura da estenose ístmica, sendo a decisão baseada na idade doente, anatomia da CoA e preferência do operador ou da instituição. Contudo, um bom resultado anatómico não evita morbilidade e mortalidade de longo prazo, apresentando cerca de metade dos doentes hipertensão arterial (HTA), e registando-se mortalidade precoce, maioritariamente devido a complicações cardiovasculares e acidentes vasculares cerebrais. O perfil tensional anómalo sugere que os resultados subótimos possam ser secundários a disfunção vascular, cuja existência foi bem documentada em doentes com CoA tratada. Existem anomalias intrínsecas da estrutura arterial e função, alterações da sensibilidade neuro-hormonal ou da regulação endócrina, e fatores adquiridos, como a idade do tratamento, que contribuem para esta disfunção vascular. Os maus resultados a longo prazo podem resultar igualmente do tipo de tratamento efetuado, que provavelmente impactam de modo diverso a rigidez do istmo aórtico e potencialmente comprometem as funções da aorta. Este efeito da modalidade terapêutica não foi até ao momento estudado. A CoA não é uma simples doença mecânica que fica resolvida quando é removido o obstáculo. Objetivos e Hipóteses: O objetivo deste estudo é comparar a função vascular entre diferentes modalidades terapêuticas de CoA. A hipótese principal é a de que os doentes submetidos a dilatação com balão têm melhor função vascular que os doentes submetidos a cirurgia ou implantação de stent, pois aquela modalidade terapêutica tem menor potencial para danificar a integridade e propriedades biomecânicas da parede da aorta do que estas. Métodos: Avaliação prospetiva da função vascular usando múltiplas modalidades não invasivas, de modo a comparar os resultados de três grupos de doentes com CoA, tratados com dilatação com cirurgia, balão ou implantação de stent, após controle das variáveis de confusão. Em doentes com CoA tratada com sucesso, comparámos prospectivamente a rigidez da aorta com tonometria de aplanação e ressonância magnética cardíaca; função endotelial com tonometria arterial periférica endotelial; analise da onda de pulso com tonometria de aplanação e tonometria arterial periférica endotelial; massa ventricular esquerda e anatomia do arco aórtico com ressonância magnética cardíaca; marcadores séricos de função endotelial, inflamação, função da parede arterial e matriz extracelular; e saúde cardiovascular ideal. A análises estatística incluiu ajuste para as variáveis de confusão. Resultados: O estudo foi realizado em sete grandes centros, de Portugal e Estados Unidos da América. Foram incluídos 75 doentes, tratado por cirurgia (n=28), dilatação com balão (n=23) e implantação de stent (n=24). Os grupos tiveram idade semelhante à data de inclusão, gravidade da CoA, gradiente residual e perfil metabólico, mas eram diferentes quanto à idade à data do tratamento. A HTA, rigidez da aorta, função endotelial e massa ventricular eram semelhantes entre os grupos. Contudo, o grupo da dilatação com balão tinha mais distensibilidade regional da aorta ascendente, menor tensão arterial (TA) sistólica durante o exercício, menos alteração da variação noturna da TA, e dose menor de biomarcadores inflamatórios. Os resultados permaneceram inalterados após ajuste das potenciais variáveis de confusão, incluindo idade à data do tratamento. Conclusões: A modalidade terapêutica não estava associada à presença de HTA, rigidez arterial global e função endotelial. Contudo, os doentes com dilatação com balão tinham um perfil de função vascular mais favorável, caracterizado por maior distensibilidade da aorta ascendente, TA noturna mais baixa, menor resposta hipertensiva no esforço e menores marcadores séricos de inflamação. São necessários mais estudos para confirmar se os nossos resultados poderão contribuir para o refinamento do paradigma de tratamento da CoA, ao adicionar ao objetivo de remoção da estenose, a preservação da função vascular, quando dois ou mais tratamentos são aplicáveis. ABSTRACT: Introduction: Congenital heart disease (CHD) affects approximately 1% of liveborns and accounts for the largest proportion of infant mortality in developed countries. Coarctation of the aorta (CoA), the 6th most common CHD, consists of a narrowing of the proximal descending aorta. If left untreated, it has an unfavorable natural history. Surgery, balloon dilation (BD) or stent implantation are all current treatments that can achieve a successful long-term removal of the stenosis, and the choice is based on age, CoA anatomy, and personal or institutional preference. Coarctation is not a mere mechanical disease that is treated by removing the increased afterload. In fact, a good anatomic result does not avoid long-term cardiovascular (CV) morbidity and mortality, with late systemic hypertension (HTN) in approximately half of the patients, and reduced life expectancy, mostly due to CV complications and stroke. The abnormal blood pressure (BP) phenotype suggests that the suboptimal results are likely due to abnormal vascular function, which has been well documented in patients with repaired CoA. There are inherent changes in the arterial structure and function, impaired neuronal sensitivity or endocrinal auto-regulation, and acquired features, such as age at treatment, that contribute to vascular dysfunction in CoA. The poor long-term vascular outcome may also be impacted by the different types of repair, which likely have differing effects on the stiffness of the repaired segment and potentially compromise both the conduit and cushioning functions of the aorta. The effects of treatment modality on long-term vascular function remain uncharacterized. Aims and Hypothesis: The goal of this study is to assess vascular function in this patient population for comparison among the treatment modalities. The central hypothesis of this study was that patients who have undergone successful BD will have better vascular function than patients who have undergone successful surgical repair or stenting since this modality is least likely to damage the integrity and biomechanical properties of the aortic wall. Methods: Prospective assessment of vascular function using multiple non-invasive modalities, and compare the results among the three groups of CoA patients previously treated using surgery, BD or stent implantation after frequency matching for confounding variables. In successfully repaired CoA patients, we prospectively compared aortic stiffness by applanation tonometry and cardiac magnetic resonance (CMR); endothelial function by endothelial pulse amplitude testing; pulse waveform analysis by applanation tonometry and endothelial pulse amplitude testing; BP phenotype by office BP, ambulatory BP monitoring, and BP response to exercise; left ventricular (LV) mass and aortic morphometrics by CMR; blood biomarkers of endothelial function, inflammation, vascular wall function, and extracellular matrix; and ideal cardiovascular health. In the statistical analysis, we adjusted for potential confounders. Results: This study was done in seven, large volume centers from Portugal and the United States of America. Participants included 75 patients treated with surgery (n=28), BD (n=23), or stent (n=24). Groups had similar age at enrollment, CoA severity, residual gradient, and metabolic profile but differed by age at treatment. Systemic HTN, aortic stiffness, endothelial function, and LV mass were similar among groups. However, BD had more distensible ascending aortas, lower peak systolic BP during exercise, less impairment in diurnal BP variation, and lower inflammatory biomarkers. The results were unchanged after adjustment for potential confounders, including age at treatment. Conclusions: Treatment modality was not associated with major vascular outcomes such as systemic HTN, global aortic stiffness, and endothelial function. However, BD patients had a better vascular phenotype profile characterized by higher ascending aorta distensibility, lower night-time BP, lower peak exercise BP and lower levels of inflammatory markers. Further studies are required to confirm if our results may contribute to refining the CoA treatment paradigm by adding to the goals of therapy the preservation of vascular function when two or more treatment techniques are applicable.

Introduction. Pipkin fractures are rare events and usually occur as a consequence for high-energy trauma. Surgery to obtain anatomical reduction and fixation is the mainstay treatment for the majority of these injuries; nonetheless, controversy exists regarding the best surgical approach. Description of the Case. We present the case of a 41-year-old male, which sustained a type II Pipkin fracture following a motorcycle accident. In the emergency department, an emergent closed reduction was performed, followed by surgery five days later. Using a surgical hip dislocation, a successful anatomical reduction and fixation was performed. After three years of follow-up, the patient presented with a normal range of motion, absent signs for avascular necrosis or posttraumatic arthritis, but with a grade II heterotopic ossification. Discussion. Safe surgical hip dislocation allows full access to the femoral head and acetabulum, without increasing the risk for a femoral head avascular necrosis or posttraumatic arthritis. Simultaneously, this surgical approach gives the opportunity to repair associated acetabular or labral lesions, which explains the growing popularity with this technique. Conclusion. Although technically demanding, safe surgical hip dislocation represents an excellent option in the reduction and fixation for Pipkin fractures.

Made available in DSpace on 2018-12-11T17:17:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-08-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) This manuscript proposes a local H∞ switched controller design for a class of uncertain nonlinear plants described by Takagi–Sugeno (T–S) fuzzy models with unknown membership functions. The control design requires only the lower and upper bounds of the system nonlinearities and of the system linear parameters, which can depend on uncertain parameters. The switched control law chooses a state-feedback controller gain, which belongs to a given set of gains, that minimizes the time derivative of a quadratic Lyapunov function. This procedure eliminates the necessity of finding the membership function expressions to implement the control law, guarantees an H∞ performance and ensures that the state trajectory remains within a region in which the T–S fuzzy model is valid. Due to the H∞ control design, that frequently results in very large control inputs, it is considered that the switched control law is subject to actuator saturation. Finally, two examples are presented. The first example studies the control of a chaotic Lorenz system. It shows that, for disturbances with large magnitude, the proposed procedures provided better results than the obtained with another recent method found in the literature, that considers full access to the membership functions. In the second example, a practical implementation of an active nonlinear suspension control system, considering an uncertain bounded mass and a fault in the actuator, confirms the effectiveness of the proposed approach. IFMS – Federal Institute of Education Science and Technology of Mato Grosso do Sul, Campus of Três Lagoas, 79.641-162 São Paulo State University (UNESP) Department of Electrical Engineering, Campus of Ilha Solteira IFPR – Federal Institute of Education Science and Technology of Paraná, Campus of Jacarezinho, 86.400-000 IFTO – Federal Institute of Education Science and Technology of Tocantins Department of Mathematics and Natural Sciences, Campus of Palmas, 77.021-090 São Paulo State University (UNESP) Department of Electrical Engineering, Campus of Ilha Solteira FAPESP: 2011/17610-0

RESUMO Objetivo: determinar, em pacientes pediátricos portadores de neoplasias malignas, as características de nódulos pulmonares identificados à tomografia computadorizada, capazes de diferenciar nódulos benignos de metástases. Métodos: estudo retrospectivo de pacientes submetidos a ressecções pulmonares de nódulos diagnosticados como metástases em um período de sete anos. Achados de tomografia e da cirurgia, assim como resultados dos exames anatomopatológicos foram comparados. Resultados: nove pacientes, submetidos a 11 intervenções cirúrgicas, foram estudados. Entre as variáveis estudadas, apenas o tamanho do nódulo, maior do que 12,5mm provou ser estatisticamente significante para predizer malignidade. Conclusão: esse estudo sugere que, entre as características tomográficas de nódulos pulmonares de crianças portadoras de neoplasias malignas, apenas o tamanho da lesão foi preditor de malignidade. ABSTRACT Objective: to determine, in pediatric patients with malignant neoplasms, the characteristics of pulmonary nodules identified on computed tomography, as well as the possibility of differentiating benign lesions from metastases. Methods: we conducted a retrospective study of patients submitted to pulmonary resections of nodules diagnosed as metastases in a period of seven years. We compared computed tomography and surgery findings, as well as results of anatomopathological examinations. Results: we studied nine patients submitted to 11 surgical interventions. Among the studied variables, only nodule size greater than 12.5mm proved to be statistically significant to predict malignancy. Conclusion: among the tomographic characteristics of pulmonary nodules in children with malignant neoplasms, only the size of the lesion was a predictor of malignancy.

A switched control design for a class of uncertain nonlinear discrete-time systems is proposed in this manuscript. The proposed procedure uses Takagi-Sugeno fuzzy models to describe the nonlinear systems and the membership functions can depend on immeasurable premise variables or uncertain bounded parameters. Based on a non-quadratic Lyapunov function, the design conditions are given in terms of Linear Matrix Inequalities (LMIs) and ensure asymptotic stability to the controlled system. In addition, a procedure that uses a linear time-invariant controller is presented. A theoretical analysis proves that if the LMI stability conditions for the closed-loop system with a time-invariant controller hold, then the LMI stability conditions, obtained using the switched control law, also hold. The both procedures do not use the membership functions to implement the control law. Finally, a numerical example illustrates the effectiveness of the proposed method and compares it with procedures found in the literature.

to determine, in pediatric patients with malignant neoplasms, the characteristics of pulmonary nodules identified on computed tomography, as well as the possibility of differentiating benign lesions from metastases.we conducted a retrospective study of patients submitted to pulmonary resections of nodules diagnosed as metastases in a period of seven years. We compared computed tomography and surgery findings, as well as results of anatomopathological examinations.we studied nine patients submitted to 11 surgical interventions. Among the studied variables, only nodule size greater than 12.5mm proved to be statistically significant to predict malignancy.among the tomographic characteristics of pulmonary nodules in children with malignant neoplasms, only the size of the lesion was a predictor of malignancy.determinar, em pacientes pediátricos portadores de neoplasias malignas, as características de nódulos pulmonares identificados à tomografia computadorizada, capazes de diferenciar nódulos benignos de metástases.estudo retrospectivo de pacientes submetidos a ressecções pulmonares de nódulos diagnosticados como metástases em um período de sete anos. Achados de tomografia e da cirurgia, assim como resultados dos exames anatomopatológicos foram comparados.nove pacientes, submetidos a 11 intervenções cirúrgicas, foram estudados. Entre as variáveis estudadas, apenas o tamanho do nódulo, maior do que 12,5mm provou ser estatisticamente significante para predizer malignidade.esse estudo sugere que, entre as características tomográficas de nódulos pulmonares de crianças portadoras de neoplasias malignas, apenas o tamanho da lesão foi preditor de malignidade.

This paper considers a class of uncertain nonlinear systems exactly described by Takagi-Sugeno T-S fuzzy models, with or without matched uncertainties and/or disturbances, within an operating region in the state space. Considering the plant subject to actuator saturation is proposed, a switched control design method such that the equilibrium point of the controlled systems is locally asymptotically stable with an adequate decay rate, for all initial conditions in a region obtained in the design procedure, that is within a given operating region. Moreover, an exact representation of the minimum function using signal functions is presented. Therefore, it is offered a bridge between the switched control and variable structure control laws, because they are usually based on minimum and signal functions, respectively. Considering the well-known approximation of the signal function by a sigmoid function, this paper introduces the 'smooth minimum' function. The smooth minimum function allowed the design of 'smooth switched' control laws, without chattering, for the aforementioned class of systems. The proposed smooth switched control laws guarantee the uniform ultimate boundedness of the controlled systems. Design examples and simulation results illustrate the control design procedures and the effectiveness of the proposed control laws. Future researches in this subject may explore the presented relationship between the switched control and variable structure control laws, in order to obtain new useful control laws. Copyright © 2016 John Wiley & Sons, Ltd.

This work presents the design and the experimental implementation of a robust state derivativefeedback (SDF) controller in an active suspension system manufactured by Quanserr (Quanser, 2009a). For thispurpose, a discrete-time SDF controller is designed in the presence of parametric uncertainties by using a statederivative model within a regional pole placement approach. In the implementations, only the measurementsfrom accelerometers are employed, a typical motivation for the use of SDF. The dynamic behavior of the activesuspension system is tested for di erent values of the uncertain parameter within its range considered in thecontroller design.