Resumo: O artigo seguinte refere-se a um estudo sobre como ocorre a transmissão psíquica entre as gerações e qual sua importância na constituição psíquica do sujeito. É também objetivo deste artigo explicar o que são as transmissões intergeracional e transgeracional. Para buscar respostas para essas questões, fez-se uma pesquisa bibliográfica sobre a transmissão psíquica, pelo viés psicanalítico, principalmente a partir da teoria lacaniana e com conceitos oriundos da linguística saussuriana. Será a partir de uma determinada ordem simbólica, constituída pela linguagem que precede o sujeito, nomeado por Lacan como o Outro, que a transmissão psíquica entre gerações ganhará o seu caráter unívoco, sempre se tendo em mente a importância fundamental do recalcamento e de seus efeitos, bem como do retorno do recalcado nas diferentes gerações. A transmissão psíquica é necessária e concomitante à constituição do sujeito, e ocorre através da linguagem, dos significantes que irão determinar uma ordem simbólica para o ser que nasce através dos diferentes discursos que perpassam as gerações nas figuras dos pais desse novo ser. Essa ordem simbólica continuará a se fazer presente nesse novo sujeito pelo restante de sua existência. Este artigo busca dar nova luz ao aspecto da transmissão psíquica transgeracional, diferenciando-se da recalque s abordagens psicanalíticas contemporâneas por ser uma leitura lacaniana. Serão usados dois exemplos: um de como a transmissão aparece na cultura, outro, na subjetividade do sujeito através da arte. Palavras-chave: Transmissão psíquica entre gerações. Interação simbólica. Constituição do Sujeito. Psicoterapia psicanalítica. Psicanálise. Abstract:The following article refers to a study on how mental transmission occurs between generations and its importance in the psychical constitution. It also aims to explain what are intergenerational and transgenerational transmissions. To answer these questions, there was a literature search on the psychic transmission, the psychoanalytical view, especially from the lacanian theory and Saussure's concepts. It will be from a particular symbolic order constituted by the language that precedes the subject, appointed by Lacan as the Other, that the psychic transmission between generations will obtain univocal character, always bearing in mind the fundamental importance of repression and its effects and the return of the repressed in other generations. The transmission is a necessary and concomitant psychic constitution of the subject through language, through the signifiers that will determine a symbolic order for the one to be born, through the different discourses that are transmitted beyond generations by the parents of this new being. This symbolic order will continue to be present in this new subject for the remainder of its existence. This article seeks to shed new light on the issue of intergenerational psychic transmission, which differentiates it from contemporary psychoanalytic approaches as a lacanian reading. Two examples will be given: one on how ...

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A recent change in the ISO 7206-2, Implants for Surgery – Partial and Total Hip Joint Prostheses – Part 2: Articulating Surfaces Made of Metallic, Ceramic and Plastics Materials, with regard to hip joint prostheses, altered the recommended cutoff for measuring the roughness of the articulating surfaces of the femoral head and acetabular cup but did not encompass two key sites: the bore head and the trunnion. The aim of this study was to evaluate whether the standardized parameters and sites established in ISO 7206-2 are appropriate for evaluating the quality of the surface finish of total hip arthroplasty implants. Three kits containing the polymeric acetabular components, metallic heads, and stems from 5 manufacturers were used for testing. Contact profilometry was performed on the internal acetabular cup, external head, head bore, and trunnion surfaces. Additionally, the external head surface was evaluated with an interferometer to increase the accuracy. The evaluation of the external surface of the femoral head with a profilometer seems to be inadequate, because of a limitation of the contact method associated with highly polished surfaces. The average roughness (Ra) values obtained with an interferometer were lower than those measured with the profilometer and revealed significant differences between the manufacturers. The use of an 0.80-mm cutoff is more appropriate for the Ra range normally found for acetabular cups, enhancing the power to detect acetabular cups with inadequate roughness. The absence of a standard for the surface finish of the stem-head interface generates heterogeneity between manufacturers and between samples produced by a single manufacturer, revealing a lack of quality control.

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Femoral stem fractures in total hip arthroplasty (THA) are a problem in clinical practice that results in great morbidity and high cost of revision hip surgery. Stem fractures are multifactorial events that are usually related to a combination of factors that increase the mechanical stress on the stem or decrease the mechanical strength of the implant. Failure analyses of hip prosthesis have identified that the presence of inadequate grain size may lead to implant failure. The aim of this article is to develop a rational to set specific sites to perform grain size measurements along stems used in THA as well as appropriate procedures to evaluate the heterogeneity of the microstructure related to the grain size distribution. In the present study, nonmodular femoral stems from three manufacturers with different wrought materials were chosen: stainless steel ISO 5832-1 (Manufacturer I), high nitrogen stainless steel ISO 5832-9 (Manufacturer II), and cobalt-chromium-molybdenum alloy ISO 5832-12 (Manufacturer III). The results of this study showed a great variability of grain size number depending on the cross section and fields evaluated. Therefore, the current technical standards for evaluating THA stems need to be modified. Analyses of grain sizes at different cross sections and inside each cross section of the stem is necessary to ensure the safety of hip stems.

Total hip arthroplasty stem fracture is an important contributor to morbidity rate and increases the cost of revision surgery. Failure is usually caused by issues related to overload, inadequate stem support, inappropriate stem design or dimensions and material processing. In this study, the role of the relationship between material characterization and biomechanical performance in the fracture of retrieved stems was explored. The stems were manufactured with forged stainless steel, had the same length, 12/14 trunnion, and 28-mm head. These stems were evaluated by macroscopic and microscopic examination to identify the causes of premature failure. Each stem was sectioned into four regions, and the cross-sections were used for the microhardness and grain size analysis. Finite element analysis (FEA) was carried out, considering the stem positioned at the femur, a musculoskeletal model, and biomechanical loading. All stems had fractured through a fatigue mechanism, mainly a unidirectional bending loading condition, with crack nucleation on the lateral side and propagation on the medial side. The numerical analysis revealed maximum mechanical stress on the lateral side of the stem neck, but this was below the yield stress calculated via the hardness. The use of a shorter head neck length could reduce the maximum mechanical stress at the neck. At a cross-section near the plane of the stem fracture, the hardness was lower than that normally reported by the ASM, and there were heterogonous and coarse grain sizes on the lateral side. The main cause of failure of the two stems analyzed was a combination of low hardness and coarse grain size, due to inappropriate materials processing, worsen by a high level of stress on the lateral side of the neck due to the large stem-head offset selected by the orthopedic surgeon.

ResumoO objetivo do presente trabalho foi avaliar e comparar a composição química e microestrutura de dois fabricantes (nacional e importado) de haste femoral fabricados em aço inoxidável austenítico ABNT NBR ISO 5832-9. As análises químicas dos principais elementos foram realizadas utilizando espectrometria de emissão ótica por descarga luminescente. A microestrutura das hastes foi caracterizada por microscopia óptica, microscopia eletrônica de varredura e difração de raios X. Medidas de dureza Vickers também foram realizadas neste estudo comparativo. As hastes nacionais e importadas exibiram pequena quantidade de partículas de nitreto (fase Z) dispersas na matriz austenítica e tamanhos de grão similares da austenita. Por outro lado, o aumento de 32% observado nos resultados de dureza da haste importada em relação à haste nacional foi atribuído às diferenças de composição química entre estas hastes. Foram identificadas microinclusões ricas em Al nas hastes importadas e microinclusões ricas em Mg nas hastes nacionais. Embora tenham sido observadas algumas diferenças entre as hastes nacionais e importadas, ambas atenderam os critérios de composição e microestrutura da norma ABNT NBR ISO 5832-9. Palavras-chave: Implante de quadril; Haste femoral; Aço inoxidável; Microestrutura. CHEMICAL AND MICROSTRUCTURAL CHARACTERIZATION OF MODULAR FEMORAL STEMS MADE OF STAINLESS STEEL ISO 5832-9. AbstractThe aim of this study was to evaluate and compare the chemical composition and microstructure of two models of femoral stem (national and imported) manufactured from ISO 5832-9 austenitic stainless steel. Chemical analyses of the key elements were performed by glow discharge optical emission spectrometry. The microstructure of the stems was characterized by optical microscopy, scanning electron microscopy and X-ray diffraction. Vickers hardness measurements were also performed in this comparative study. The national and imported stems exhibited small amount of nitride particles (Z-phase) dispersed in the austenitic matrix and similar grain sizes of austenite. On the other hand, the hardness was 32% higher in the imported stem, which was attributed to the differences in composition between the stems. Al-rich and Mg-rich inclusions were identified in the imported and national stems, respectively. Although some differences have been observed between national and imported stems, both met the criteria of composition and microstructure of the ISO 5832-9 standard.