A PROIBIÇÃO DO COMPORTAMENTO CONTRADITÓRIO NO DIREITO BRASILEIRO

O artigo analisa o instituto conhecido como venire contra factum proprium, que se apresenta como corolário do princípio da boa-fé objetiva e, mais amplamente, da tutela da confiança. Trata-se, em suma, da vedação do comportamento contraditório nas relações jurídicas. Verificam-se os elementos necessários à aplicação da proibição: atuação material inicial, expectativa legítima de manutenção do comportamento, investimento, econômico ou não, refletido em prejuízo, e duplo nexo de causalidade (entre a atuação inicial e a expectativa e entre a expectativa e o dano). Aborda-se a visão do instituto em ramos diversos do direito, com suas peculiaridades. Por fim, delimitam-se as consequências possíveis de sua violação: obrigação de contratar, de aceitar o contrato nulo e de indenizar

A novel methodology to restrict the range of motion of human articulations

The human movement has long been a subject of extensive investigation by many authors, involving a vast interest in both clinical and sports applications. The use of biomechanical models of the human body can greatly contribute to the advancement of the body of knowledge in this scientific field as they provide rigorous information on several key biomechanical parameters. Thus, the modeling of human articulations must realistically reproduce their behavior and, therefore, to consider a restricted range of motion (RoM). The RoM is influenced by the bony structures adjacent to the articulations and by the physiological characteristics of the connective tissues, such as muscles and ligaments, surrounding them. This parameter varies amongst subjects and according to the type and anatomical location of each articulation. However, in the multibody systems methodology, the violation of the RoM for a particular joint can be clearly noted if geometrically ideal joints are used. This occurs since no additional constraints are introduced in the joint’s formulation to prevent it from acquiring unfeasible positions. To provide a solution for this problem, in this work, a novel methodology to restrict the RoM of human articulations is proposed within the framework of multibody systems methodologies. Joint resistance moments are applied to simulate the passive resistant behavior of the connective tissues existing around human articulations and to prevent physiologically unfeasible positions of the contiguous bony structures. A three-dimensional biomechanical model of the human lower leg and foot is used as a demonstrative example of application of the proposed methodology, focusing on the ankle articular complex. The results compare the dynamic behavior of the model with and without the application of the joint resistance moments and lead to the conclusion that the proposed methodology allows the correct restriction of the joints’ RoM, while preserving the mechanical energy of the system

Current evidence on biomechanical modeling for the analysis of crutch-assisted gait

Crutches are utilized as a mean of locomotion by patients with a variety of long-term disabilities, such as cerebral palsy or spinal cord injury. These assistive devices help reducing the load imposed on the injured lower extremities, while allowing an upright posture. However, crutch-assisted gait places a considerable repetitive effort on the upper extremities (UE), which are not adapted to weight-bearing tasks, thus contributing to the onset of secondary health conditions. Due to the raising significance of this problem, the research on biomechanical modeling strategies for the analysis of the loads imposed on the UE during crutch-assisted gait has been growing. The resulting scientific knowledge may provide promising options for the improvement of crutch design based on patients’ biomechanical outcomes and, thus, a detailed evaluation of this topic is strongly warranted. This has been the main motivation for preparing this review, which provides a comprehensive discussion and summary of the biomechanical modeling strategies currently available in the literature used to study crutch-assisted gait. PubMed, Scopus, and Web of Science electronic databases were searched on July 2021, and 18 studies, dated from 1985 to 2021, were included. Six studies used commercial software (OpenSim or Anybody), while the remaining developed in-house codes. Fifteen studies considered three-dimensional biomechanical models, among which six focused on the UE, eight modeled the entire human body and one did not provide this information. Musculoskeletal models were considered only in 17% of all studies. Three strategies were used to incorporate crutches on the biomechanical models, namely defining this assistive devices as a rigid body independent of the forearm/hand, imposing a position constraint on the glenohumeral joint, and using an arm/crutch or forearm/crutch system as a single rigid body. Forces exerted on the glenohumeral, elbow and wrist articulations during swing-through crutch gait were double the ones during reciprocal gait

A foot-ground contact model for human motion analysis

Over the last decades, there has been a growing interest in the area of contact-impact modeling and analysis in the context of multibody system dynamics. However, it remains a difficult task to accurately model the contact mechanics when the geometric and material properties are of complex natures, such as in the case of the human foot-ground interaction. Bearing that in mind, the foot is the main source of interaction with the surrounding environment for most people, since it is the only part of the human body that is in contact with the ground and, therefore, contact models that describe the human foot-ground interaction are of extreme importance for biomechanical analysis. Thus, to accurately replicate the human motion during the analysis of biomechanical multibody systems, the computational models must consider realistic representations of the foot and appropriate numerical descriptions of its interaction with the ground surface. In this sense, the main purpose of this work is to present a two-dimensional biomechanical multibody model to describe the foot-ground contact. The interaction between the foot and the ground is geometrically defined by circles positioned at specific locations on the foot plantar surface, and a plane, describing the ground. The contact is detected based on the relative interpenetration of the surfaces, and appropriate constitutive laws associated with the normal and tangential forces developed during the contact are applied. With the purpose of correctly determining the contact forces, an optimization process is implemented to obtain the most suitable values for the geometric and contact parameters of the proposed model. Finally, the results obtained from computational and experimental analysis are compared using a multibody model of the right side of human body, with the aim of validating the proposed approach.This work has been supported by Portuguese Foundation for Science and Technology, under the national support to R&D units grant, with the reference project UIDB/04436/2020 and UIDP/04436/2020, as well as through IDMEC, under LAETA, project UIDB/50022/2020. The second author expresses her gratitude to the Portuguese Foundation for Science and Technology through the PhD grant (2021.04840.BD)

Cultura, memória e literatura: a infância em obras autobiográficas de Bartolomeu Campos de Queirós

This study discusses the relationship between Culture, Memory and Literature from the analysis of literary texts on childhood: Por Parte de Pai e Ler, Escrever e Fazer Conta de Cabeça de Bartolomeu Campos de Queirós. It addresses the diversity of perceptions about childhood, understood as a symbolic construction historicaland cultural partner, taking some historical examples of this representation. It studies, as the author transfers FOR fictional plan, through the memory, his childhood elements.Este trabalho discute a relação entre cultura, memória e literatura a partir da análise dos textos literários sobre a infância: Por parte de pai e Ler, escrever e fazer conta de cabeça, de Bartolomeu Campos de Queirós. Aborda a diversidade de percepções sobre a infância, compreendida como uma construção simbólica sócio-histórica e cultural, tomando alguns exemplos históricos desta representação. Apresenta, ainda, como o autor transfere para o plano ficcional, através da memória, elementos de sua infância

Multibody dynamics in robotics with focus on contact events

Multibody dynamics methodologies have been fundamental tools utilized to model and simulate robotic systems that experience contact conditions with the surrounding environment, such as in the case of feet and ground interactions. In addressing such problems, it is of paramount importance to accurately and efficiently handle the large body displacement associated with locomotion of robots, as well as the dynamic response related to contact-impact events. Thus, a generic computational approach, based on the Newton-Euler formulation, to represent the gross motion of robotic systems, is revisited in this work. The main kinematic and dynamic features, necessary to obtain the equations of motion, are discussed. A numerical procedure suitable to solve the equations of motion is also presented. The problem of modeling contacts in dynamical systems involves two main tasks, namely the contact detection and the contact resolution, which take into account for the kinematics and dynamics of the contacting bodies, constituting the general framework for the process of modeling and simulating complex contact scenarios. In order to properly model the contact interactions, the contact kinematic properties are established based on the geometry of contacting bodies, which allow to perform the contact detection task. The contact dynamics is represented by continuous contact force models, both in terms of normal and tangential contact directions. Finally, the presented formulations are demonstrated by the application to several robotics systems that involve contact and impact events with surrounding environment. Special emphasis is put on the systems’ dynamic behavior, in terms of performance and stability

Current perspectives on the modeling of the foot-ground interaction for human motion analysis

Contact-impact events are multifaceted phenomena because their modeling process strongly depends on multiple factors, such as the geometry of the contacting surfaces, the local physical properties of the materials, and the numerical representation of the interaction between the contacting bodies. In particular, when the geometric and material properties are of complex nature, it is still a quite challenging problem to accurately represent the contact mechanics. This is the case of the human foot-ground interface. The dynamic simulation of the human motion is conditioned by the foot-ground contact forces since the response of muscles, ligaments and articular reaction forces and moments is highly affected by them. Therefore, the accuracy of contact models that describe the human foot-ground interaction play a key role in biomechanical dynamic simulations. Several formulations to mimic the human foot-ground interaction have been proposed in the literature, which provide numerical approaches to calculate the ground reaction forces without the need of any experimental measurement. This work reviews and discusses the methodologies utilized to study the foot-ground interaction in human locomotion available in the literature. For this purpose, PubMed, Web of Science and Scopus electronic databases were searched on September 2021 to identify publications focusing on foot-ground contact modeling strategies. A total of 30 papers, dated from 1995 to 2020, were selected and thoroughly analyzed. Different contact geometries were established with the goal of defining the foot and ground surfaces, in which the most common were based on points, circles, ellipses, spheres, ellipsoids and surfaces obtained from 3D scanning procedures. Regarding the contact resolution, the formulations based on contact force approaches were preferred to the methods based on geometrical constraints. Several studies considered both computational and experimental approaches. One of the main limitations reported in the analyzed papers dealt with the restriction of the motion to the sagittal plane

Tongue function and swallowing in individuals with temporomandibular disorders

The tongue participates in the oral phase of swallowing by pushing the food bolus toward the oropharynx. This relationship between tongue function and swallowing is little addressed addressed in individuals with temporomandibular dysfunction (TMD). Objective: To analyze the association of functional tongue conditions on swallowing in individuals with TMD. Methodology: After approval by the Institutional Review Board, the study was conducted on 30 individuals of both sexes, aged 18 to 28 years, with TMD, and not treated for the disorder. Tongue function was assessed as to the mobility, pressure, and oral motor control. Swallowing was analyzed by clinical assessment during ingestion of solid (wafer biscuit) and liquid (water). Data regarding mobility and swallowing were collected using the orofacial myofunctional evaluation protocol. Tongue pressure was measured by the Iowa Oral Performance Instrument, during elevation, protrusion, swallowing, and resistance test. The oral motor control was assessed by the oral diadochokinesis (DDK) test by rapid and repeated emissions of syllables “ta” and “ka”. Data were statistically analyzed by the Spearman correlation coefficient, at a significance level of 5%. Results:Relationships were found between tongue function and swallowing for the following aspects: mobility (r=0.741), pressure in protrusion (r=-0.366), swallowing of saliva (r=-0.499), mean DDK rate in emissions “ta” (r=-0.424) and “ka” (r=-0.446), and mean DDK period in emissions “ta” (r=0.424) and “ka” (r=0.446). Thus, the greater the change in tongue mobility, the lower the tongue pressure in protrusion and swallowing of saliva, the lower the emissions per second, the longer the mean time between vocalizations, and the worse the swallowing of individuals with TMD. Conclusion: The functional conditions of the tongue regarding mobility, pressure, and oral DDK were associated with swallowing in individuals with TMD

Comparison of the accuracy of different transfer impression techniques for osseointegrated implants

The aim of this study was to evaluate 3 transfer techniques used to obtain working casts of implant-supported prostheses through the marginal misfit and strain induced to metallic framework. Thirty working casts were obtained from a metallic master cast, each one containing 2 implant analogs simulating a clinical situation of 3-unit implant-supported fixed prostheses according to the following transfer impression techniques: group A, squared transfers splinted with dental floss and acrylic resin, sectioned, and re-splinted; group B, squared transfers splinted with dental floss and bis-acrylic resin; and group N, squared transfers not splinted. A metallic framework was made for marginal misfit and strain measurements from the metallic master cast. The misfit between the metallic framework and working casts was evaluated with an optical microscope following the single-screw test protocol. In the same conditions, the strain was evaluated using strain gauges placed on the metallic framework. The data were submitted to one-way analysis of variance followed by the Tukey test (α = 5%). For both marginal misfit and strain, there were statistically significant differences between groups A and N (P < .01) and groups B and N (P < .01), with greater values for group N. According to the Pearson test, there was a positive correlation between the misfit and strain variables (r = 0.5642). The results of this study showed that the impression techniques with splinted transfers promoted better accuracy than the nonsplinted technique, regardless of the splinting material used41666266

Light stimulation on tenocytes: A systematic review of in vitro studies

Background: The purpose of this systematic review is to analyze the methodologies, utilized stimulation parameters, and the main cellular outcomes obtained by in vitro studies that apply a light source on tenocyte cultures. Methods: The PubMed, Scopus, and Web of Science databases were searched up to December 9, 2019 for in vitro studies that used light sources on tenocyte cultures. A 13-item checklist was used to assess methodological quality of the studies and the risk of bias was assessed using the Risk of Bias Assessment tool for Non-randomized Studies tool. Results: Six studies were included. Tenocytes from the Achilles tendon were used by 83.3% of the studies, with 16.7% utilizing the deep digital flexor tendon, with cells in passage 2 to 5. Four studies used lasers and the other 2 used light-emitting diode or intense pulsed light, in wavelengths ranges from 530 to 1100 nm. The application of light to tenocytes resulted in positive effects reported by all studies, including an increase in cell proliferation and migration, and higher protein and gene expression of tendon biomarkers. Studies presented a lack of standardization on reporting light stimulation parameters and experimental methodologies, leading to low methodological quality. There was a high risk of selection, performance, detection, and reporting bias. Conclusions: All studies showed positive effects after light stimulation on tenocytes, regardless of the light source used. However, the lack of standardized data on light stimulation parameters, experimental setup, and the studies’ main limitations hindered representative conclusions and comparisons amongst studies’ main outcomes