Abstract This teaching case portrays the dilemma of ZM S/A, an auto parts industry, regarding the disruption of B2B to B2C sales channels. With the growing demand for sales through online channels due to the COVID-19 pandemic, the company puts into perspective the feasibility of starting direct sales operations (B2C) through the creation of its own e-commerce or the promotion of its distributors’ online sales. The purpose of the case is to promote reflection on the strategic changes in sales channels and the potential conflicts of creating an e-commerce platform. This is a real case that uses the company’s name and replaces the names of individuals involved for privacy. The construction of the case relied on primary sources, through interviews with those involved, and on secondary sources, through sectoral data. The case can be applied in the final years of undergraduate programs in business administration and graduate programs in strategic marketing and digital marketing, specifically in courses related with business management, organization and marketing strategies, operations management, and innovation.

Resumen Este caso didáctico retrata el dilema de ZM S/A, una industria de autopartes, con respecto a la disrupción de los canales de venta B2B a B2C y sus posibles conflictos. Con la creciente demanda de ventas a través de canales online a raíz de la pandemia de COVID-19, la compañía pone en perspectiva la viabilidad de iniciar operaciones de venta directa (B2C), mediante la creación de un e-commerce propio o del fomento de las ventas de sus distribuidores. El propósito del caso es promover la reflexión sobre los cambios estratégicos en los canales de venta y los posibles conflictos en el cambio de estos canales en un sector con estructura enyesada, pero que ha ido cambiando su formato debido al acceso digital de los consumidores. Este es un caso real en el que se usa el nombre real de la empresa. Solo los nombres de los personajes son ficticios. La construcción del caso se basó en fuentes primarias, a través de entrevistas a los involucrados, y en fuentes secundarias, a través de datos sectoriales. El caso puede aplicarse en los últimos años de carreras de grado en administración y en posgrados en marketing estratégico y marketing digital, específicamente en disciplinas que involucren gestión empresarial, estrategias organizacionales y de marketing, gestión de operaciones e innovación.

Resumo Este caso para ensino retrata o dilema da ZM S/A, uma indústria de autopeças, ante a ruptura de canais de vendas, que passaram de B2B para B2C, e seus potenciais conflitos. Com a crescente demanda das vendas nos canais on-line em virtude da pandemia de COVID-19, a empresa coloca em perspectiva a viabilidade de iniciar operações de venda direta (B2C), com a criação de um e-commerce próprio ou fomentando as vendas de seus distribuidores. O objetivo do caso é promover a reflexão sobre as mudanças estratégicas dos canais de vendas e os potenciais conflitos na mudança destes canais em um setor com estrutura engessada, mas que vem mudando seu formato por uma demanda do acesso digital dos consumidores. Trata-se de um caso real, que retrata o nome verdadeiro da empresa. Apenas os nomes dos personagens foram são fictícios. A construção do caso contou com fontes primárias, via entrevistas com os envolvidos, e fontes secundárias, que foram os dados setoriais. O caso pode ser aplicado nos anos finais dos cursos de graduação em Administração e em cursos de pós-graduação em Marketing Estratégico e Marketing Digital, especificamente em disciplinas que envolvem a gestão empresarial, estratégias organizacionais e de marketing, gestão de operações e inovação.

ABSTRACT Antimicrobial photodynamic therapy (aPDT) involves the association of a photosensitizing agent with a light source with the goal of causing apoptosis or microbial lysing. The use of compounds with natural active principles is gaining prominence throughout the world. Several studies from groups that are linked to the development of innovations in the pharmaceutical market have used natural dyes, such as curcumin, the efficacy of which has been demonstrated in aPDT trials. Difficulties related to physicochemical stability, solubility and cell penetration are some of the challenges associated with this field. The present work aimed to prepare, investigate the characteristics and improve the photodynamic activity of PLGA-based nanoparticles loaded with curcumin for use in aPDT therapy. Using the simple technique of emulsion during the evaporation of a solvent, the particles were built, characterized and tested against microorganisms with importance for medicine and dentistry. The results revealed that the particles were able to protect the curcumin against degradation and eliminate some microorganism species at nanomolar concentrations.

ABSTRACT OBJECTIVE: In 1996, the Brazilian cardiovascular surgeon, Dr. Randas Batista, introduced a surgical technique called partial left ventriculectomy, where he admitted the possibility of reducing the diameter of the left ventricle through the sectioning of one section of its wall. After the publication of this study, thousands of case reports and procedure analysis have been published, and due to several disappointing results, many doctors and institutions failed to execute it. As the main objective of this study, stands out the search for success cases of ventriculectomy in the last 12 years and if during this period it was achieved some significant development in this procedure that allows obtaining lower mortality rate postoperatively. METHODS: Systematic review of indexed scientific literature over the past 12 years and the term "Partial Left Ventriculectomy". RESULTS: There has been a considerable number of reported successful cases and highly significant findings in regard to determining the most suitable region for the section, proper selection of the patients indicated to the procedure, including the influence of the coronary artery anatomy in the nomination procedure and the need for preservation of ventricular geometry to ensure better quality of ventricular contractions after the sectioning. CONCLUSION: This surgical procedure has been successfully performed, mainly in Japan, improvements in its efficiency were found and the need for a mathematical modeling of the slice to be severed is a prominent factor in many studies.

Introduction Thermography is a surface thermal radiation measurement technique whose application has been expanding in the healthcare field. The unhealed wound is a serious public health problem because it intervenes in the quality of life of patients and may cause emotional and psychological losses. The wound temperature can provide quantitative data that allow for the healing process to be monitored. The aim of this study was to verify whether thermography can be used as a method to evaluate the healing of pressure ulcers. Methods Eight participants with sacral pressure ulcers were recruited and randomly divided into two groups: A (control) and B (experimental). Both groups received standard treatment for a period of four weeks, which consisted of a daily cleaning of the pressure ulcers with physiological saline (sodium chloride 0.9%) followed by an alginate hydrogel dressing. The group B received light-emitting diode (LED) phototherapy in addition to standard treatment, three times a week, yielding a total of 12 sessions. Photographs and thermograms of each pressure ulcer were obtained in all sessions in both groups. Results Pressure ulcers treated with LED phototherapy were healed. The pressure ulcer area of group B decreased over the 12 treatment sessions, whereas the pressure ulcer area of group A increased. The ulcer temperature of group B was higher than that of group A during the treatment (temperature difference up to 7.6%). Discussion The present study suggests a relationship between the temperature and area of pressure ulcers and proposes thermography as an adjunctive method for the evaluation of healing processes.

Several studies demonstrate the benefits of low-power light therapy on wound healing. However, the use of LED as a therapeutic resource remains controversial. There are questions regarding the equality or not of biological effects promoted by LED and LASER. One objective of this review was to determine the biological effects that support the use of LED on wound healing. Another objective was to identify LED´s parameters for the treatment of wounds. The biological effects and parameters of LED will be compared to those of LASER. Literature was obtained from online databases such as Medline, PubMed, Science Direct and Scielo. The search was restricted to studies published in English and Portuguese from 1992 to 2012. Sixty-eight studies in vitro and in animals were analyzed. LED and LASER promote similar biological effects, such as decrease of inflammatory cells, increased fibroblast proliferation, stimulation of angiogenesis, granulation tissue formation and increased synthesis of collagen. The irradiation parameters are also similar between LED and LASER. The biological effects are dependent on irradiation parameters, mainly wavelength and dose. This review elucidates the importance of defining parameters for the use of light devices.

INTRODUCTION: The present study proposes a new scientific project for the seat of a wheelchair, suggesting that, through the properties of a three plan mobile seat, the pelvis of individuals with neuromotor dysfunctions may position themselves adequately, allowing a chain effect, with innumerable benefits to the users, such as prevention of deformities, of muscle shortening, of pressure ulcers and improved functionality. In spite of innumerable wheelchair models available in market, none presents the ample properties resembling the articulated seat, allowing the pelvic alignment that is crucial for the adoption of an adequate posture. METHODS: The articulated seat was set over a ball and socket articulation made of two components, one convex that is fixed in the chair's structure and the other concave, attached to a mobile platform. The property of the articulated seat, to change the pressure distribution in the gluteal region, was tested on 34 typical individuals, without neurological injury, through a measurement system composed by 27 sensors. RESULTS: The significance of the statistic model proposed determined that the articulated seat was capable of altering the pressure distribution in the gluteal region in several positions on the frontal and sagittal planes, in healthy subjects. CONCLUSION: Despite the fact that this equipment is capable of redistributing the pressure in a seating position, future research to examine other parameters such as time of use, the use in subjects with neurological dysfunction, the angle of pelvic inclination, the criterions of indication and non-indication, inter alia, must be conducted to appropriately qualify this device.

As mastites estão entre as principais causas de prejuízo para produtores de leite. Em casos graves de hiperqueratose, o canal do teto pode se tornar uma barreira mais fácil para que as bactérias penetrem na glândula mamária. Os objetivos deste estudo foram avaliar um dispositivo fotobiomodulador de LED para tratamento e prevenção de hiperqueratose de teto e prevenção da mastite subclínica em um rebanho de leite com alta prevalência de hiperqueratose (35,3% de casos graves). Foram utilizadas 60 primíparas para o experimento de prevenção e 30 vacas com hiperqueratose para o experimento terapêutico. Em ambos os experimentos, metade dos animais foram tratados com o dispositivo fotobiomodulador três vezes por semana, durante 6 semanas. Os outros animais foram os controles. Imagens fotográficas digitalizadas foram realizadas na avaliação inicial e, semanalmente, por 6 semanas consecutivas. Nas primíparas, novas avaliações foram realizadas entre 6 e 7 meses de lactação. Para avaliação da mastite subclínica, contagem de células somáticas (CCS) foram feitas mensalmente. No experimento preventivo, o diâmetro externo das lesões permaneceu constante nos tetos do grupo tratado, enquanto houve aumento no grupo controle. No experimento terapêutico não foram observadas diferenças estatísticas entre as variáveis de hiperqueratose. Contudo, o grupo tratado apresentou menor incidência de mastites subclínicas (CCS < 250 células/mL) por lactação do que o grupo controle (P<0,05). Em conclusão, o tratamento não foi efetivo em prevenir o desenvolvimento ou reduzir lesões instaladas de hiperqueratose de teto. Contudo, o uso protótipo se mostrou útil e promissor como adjuvante na prevenção do aumento de tamanho das lesões de hiperqueratose de teto em primíparas e como forma de reduzir incidência de mastite subclínicas em vacas leiteiras já acometidas.

Mastitis consistis one of the main problems of milk production, mainly due to the production losses and the rising cost of milk. In case of severe hyperkeratosis, the teat canal can become an easier barrier for the bacteria to penetrate. The objeSctive of this study was to assess a phototherapy device construct with LED light for prevention and treatment of teat hyperkeratosis in a dairy cattle herd with high prevalence (35.3% of severe cases). 60 primiparous cows were used in the preventive experiment and 30 cows with hyperkeratosis were used in the therapeutic experiment. In both experiments, half of the cows started to be treated in early lactation using the phototherapy device three times per week for 6 weeks. The other cows were the controls. Hyperkeratosis was assessed by scoring and by morphometric analyses of teat images that were taken at baseline and then weekly for 6 consecutive weeks. In the preventive experiment, more images were taken later, between 6 and 7 months of the first lactation. Somatic cell counts (SCC) were performed monthly. In the preventive experiment, the outer diameter of the teat lesions remained constant in the treated group, whereas cows of the control group showed a significant increase at the end of lactation. In the therapeutic groups, no statistical differences for teat hyperkeratosis variables were seen between groups. However, the incidence of subclinical mastitis (SCC > 250 cells/mL) during lactation was lower in the treated group (P<0.05). In conclusion the phototherapy protocol did not prevent the development in primiparous or ameliorate previous hyperkeratosis lesions in cows. However, the prototype was considered useful as an adjunct in preventing the increase in the size of teat hyperkeratosis lesions and also as a way to reduce subclinical mastitis incidence in affected dairy cows.

OBJETIVO: Avaliar se a análise dos marcadores imunoistoquímicos obtidos por meio de espécimes de core biopsy (CB) refletem com precisão o perfil dos marcadores tumorais obtidos por biópsia cirúrgica excisional (BCE). MÉTODOS: Estudo retrospectivo usando dados da Divisão de Mastologia do Hospital das Clínicas de São Paulo. Sessenta e nove pacientes submetidas à CB guiada por ultrassom com diagnóstico de câncer de mama foram analisadas retrospectivamente. O exame imunoistoquímico dos espécimes de CB foram comparados com aquele obtido a partir da BCE em relação ao receptor de estrogênio (RE), receptor de progesterona (RP), human epidermal gowth factor receptor 2 gene (HER2), p53 e Ki-67. A análise de concordância entre a CB e a BCE foram realizados usando o coeficiente de kappa (k) (IC 95%). RESULTADOS: A concordância perfeita entre a BCE e a CB do p53 (k = 1,0; IC 95%: 0,76-1,0) foi identificada. A concordância foi quase perfeita para o RE (k = 0,89; IC 95%: 0,65-1,0) e concordância substancial foi identificada para o RP (= 0,70; IC 95%: 0,46-0,93). O HER2 (k = 0,61; IC 95%: 0,38-0,84) e Ki-67 (k = 0,74; IC 95%: 0,58-0,98) obtiveram uma concordância substancial nesta análise. CONCLUSÃO: os resultados deste estudo indicam que a análise imunoistoquímica do RE, RP, Ki-67 e p53 a partir dos espécimes de CB fornecem resultados que refletem com precisão o perfil dos marcadores do tumor. O HER2 foi menos consistente, porque apesar de ter produzido uma concordância substancial, os valores foram muito próximos da concordância moderada.

OBJECTIVE: To evaluate whether immunohistochemical marker studies performed on core needle biopsy (CNB) specimens accurately reflect the marker status of the tumor obtained from final surgical specimen. METHODS: This was a retrospective study that used the database of the Division of Mastology of the Hospital das Clínicas, São Paulo, Brazil. Sixty-nine patients submitted to ultrasound-guided CNB diagnosed with breast cancer were retrospectively analyzed. Immunohistochemistry (IHC) on core biopsy specimens was compared to that of excisional biopsy regarding estrogen receptor (ER), progesterone receptor (PR), human epidermal gowth factor receptor 2 gene (HER2), p53, and Ki67. The analysis of the concordance between CNB and surgical biopsy was performed using the kappa (k) coefficient (95% CI). RESULTS: A perfect concordance between the labeling in the surgical specimens and the preoperative biopsies in p53 (k = 1.0; 95% CI: 0.76-1.0) was identified. There was an almost perfect concordance for ER (k = 0.89; 95% CI: 0.65-1.0) and a substantial concordance for PR (k = 0.70; 95% CI: 0.46-0.93). HER2 (k = 0.61; 95% CI: 0.38-0.84) and Ki-67 (k = 0.74; 95% CI: 0.58-0.98) obtained a substantial concordance this analysis. CONCLUSION: The results of this study indicate that the immunohistochemical analysis of ER, PR, Ki-67, and p53 from core biopsy specimens provided results that accurately reflect the marker status of the tumor. The concordance rate of HER2 was less consistent; although it produced substantial concordance, values were very close to moderate concordance.

Vários estudos apontam que o treinamento com vibrações pode contribuir no desenvolvimento da força muscular e do desempenho esportivo. O objetivo deste estudo foi verificar o efeito da vibração mecânica aplicada na direção da resultante das forças musculares sobre a impulsão vertical. A amostra foi composta por 18 voluntários que realizaram o teste de salto vertical antes e após 20 segundos de vibração mecânica, 20 Hz de frequência e 6 mm de amplitude, aplicada na direção da resultante das forças musculares. Os mesmos voluntários foram utilizados como controle e, para isto, realizaram pré e pós-teste sem treinamento com vibração. Houve um aumento significativo de 8,5% na altura de salto vertical após o treinamento com vibração. O procedimento controle não gerou alterações significativas. Estes resultados sugerem que a aplicação de vibração mecânica na direção da resultante das forças musculares de membros inferiores foi capaz de gerar aumentos agudos na impulsão vertical.

Several studies have indicated that vibratory training can contribute to the development of muscle strength and sports performance. The aim of this study was to investigate the effect of mechanical vibration application in the direction of the result of muscle forces vector addition on vertical jump. Eighteen volunteers performed vertical jump test 20 s before and after the application of mechanical vibration of 20 Hz and 6 mm amplitude in the direction of the result of muscle forces vector addition. The same volunteers were used as control group by performing the vertical jump test without pre- and post-test vibration application. The vibratory training caused an significantly increase of 8,5% at vertical jump height while jump height did not vary significantly in the control experiment. These data suggest that the application of mechanical vibration in the direction of muscle forces vector addition can increase the performance in vertical jumps.

FUNDAMENTOS: Trichophyton rubrum é o agente mais comum das micoses superficiais de pele e unhas causando infecções de longa duração e altas taxas de recidiva. As desvantagens do tratamento atual envolvem medicações tópicas as quais não são capazes de alcançar o leito ungueal em concentrações terapêuticas, antifúngicos sistêmicos que não erradicam o fungo antes das unhas serem renovadas, efeitos colaterais graves e seleção de isolados fúngicos resistentes. A terapia fotodinâmica tem sido uma alternativa promissora aos tratamentos convencionais. OBJETIVOS: Este estudo avaliou a eficácia, in vitro, de azul de orto-toluidina irradiado por diodo emissor de luz na redução da viabilidade de T. rubrum. MÉTODOS: O inóculo fúngico foi preparado e exposto a diferentes concentrações de azul de orto-toluidina e densidades de energia do diodo emissor de luz, para avaliar a sensibilidade de T. rubrum e o efeito fungicida, após terapia fotodinâmica. Além disso, os perfis da área e volume das suspensões fúngicas irradiados também foram investigados. RESULTADOS: Uma pequena redução, in vitro, de células fúngicas foi observada após a exposição a 100 mM azul de orto-toluidina irradiados por diodo emissor de luz a 18 J/cm². Efeito fungicida ocorreu após irradiação 25 µM orto-toluidina por diodo emissor de luz com densidade de energia de 72 J/cm². A análise mostrou que a área e o volume irradiados pelo diodo emissor de luz foram 52,2 mm² e 413,70 mm³, respectivamente. CONCLUSÕES: Os resultados permitiram concluir que a terapia fotodinâmica com diodo emissor de luz, nas condições experimentais é uma abordagem alternativa para inibir, in vitro, T. rubrum e pode ser um tratamento promissor para as dermatofitoses causadas por este fungo.

BACKGROUND: Trichophyton rubrum is the most common agent of superficial mycosis of the skin and nails causing long lasting infections and high recurrence rates. Current treatment drawbacks involve topical medications not being able to reach the nail bed at therapeutic concentrations, systemic antifungal drugs failing to eradicate the fungus before the nails are renewed, severe side effects and selection of resistant fungal isolates. Photodynamic therapy (PDT) has been a promising alternative to conventional treatments. OBJECTIVES: This study evaluated the in vitro effectiveness of toluidine blue O (TBO) irradiated by Light emitting diode (LED) in the reduction of T. rubrum viability. METHODS: The fungal inoculums' was prepared and exposed to different TBO concentrations and energy densities of Light emitting diode for evaluate the T. rubrum sensibility to PDT and production effect fungicidal after photodynamic treatment. In addition, the profiles of the area and volume of the irradiated fungal suspensions were also investigated. RESULTS: A small reduction, in vitro, of fungal cells was observed after exposition to 100 µM toluidine blue O irradiated by 18 J/cm² Light emitting diode. Fungicidal effect occurred after 25 µM toluidine blue O irradiation by Light emitting diode with energy density of 72 J/cm². The analysis showed that the area and volume irradiated by the Light emitting diode were 52.2 mm² and 413.70 mm³, respectively. CONCLUSION: The results allowed to conclude that Photodynamic therapy using Light emitting diode under these experimental conditions is a possible alternative approach to inhibit in vitro T. rubrum and may be a promising new treatment for dermatophytosis caused by this fungus.

Instrumentos confiáveis e válidos são necessários para avaliar a efetividade das técnicas de reabilitação. O objetivo deste estudo foi avaliar a confiabilidade e a validade do Hidropletismômetro. Quatorze sujeitos com idade entre 18 e 59 anos foram selecionados para participar do estudo. Os tornozelos foram avaliados por dois examinadores treinados com o Hidropletismômetro. Três medidas de cada tornozelo foram obtidas pelos examinadores de forma aleatória para investigar a confiabilidade intra e inter-examinadores. Foram também obtidas vinte e seis medidas com o Hidropletismômetro e comparadas com as medidas obtidas com o Deslocador de Água considerado "padrão ouro", através de provetas de vidro graduadas de 10 ml a 1000 ml. A confiabilidade intra e inter-examinadores foi realizada através do Coeficiente de Correlação Intraclasse (CCI) e a validade através do teste t pareado. O Coeficiente de Correlação de Pearson foi utilizado para estabelecer a associação entre os dois instrumentos. Os dados demonstraram níveis de confiabilidade intra e inter-examinadores com (CCI)3,1 = 0,99 e (CCI)3,2 = 0,99, respectivamente. Nenhuma diferença foi encontrada entre as medidas obtidas com o Hidropletismômetro e as obtidas com as provetas (p=0,404). A Correlação de Coeficiente de Pearson mostrou alta magnitute e nível de significância entre as medidas (r=1,0; p<0,0001). Os resultados evidenciaram que o Hidropletismômetro é um instrumento confiável e válido para medida de volume do tornozelo/pé.

Reliable and valid instruments are necessary to evaluate the effectiveness of the rehabilitation techniques.The objective this study was to evaluate the reliability and the validity of the water plethysmography. Fourteen subjects between the ages of 18 and 59 years were selected to participate in the study. Ankles were assessed by two trained examiners with the water plethysmography. Three measures of each ankle were obtained by the two investigators to evaluate intra- and inter-raters reliability. Twenty-six measures were obtained with the water plethysmography and compared with measurements obtained by graduated cylinders from 10 to 1000 ml, water displacement device (gold standart). Intraclass correlation coefficients (ICCs) evaluated intra- and inter-raters reliability, whereas paired Student t-tests and Pearson's correlation coefficients were used to establish validity of the water plethysmography.The results demonstrated excellent intra- and inter-rater reliability levels with levels with CCI3,1=0.99 and CCI3,2=0.99 respectively. No differences were found between the measures obtained with the water plethysmography compared to those of the water displacement device (p=0.40). Pearson's correlation coefficient showed a high magnitude and significance level between the measures (r=1,0; p<0.0001).The findings demonstrated that the water plethysmography is a reliable and valid instrument for measuring ankle/foot volume.

The objective of this study was to validate the reprocessing of angiographic cardiac catheters regarding their characteristics of mechanical functionality and the molecular and micro-structural integrity of the polymeric chain. This is an experimental, applied, comparative and controlled study. A simulation set was built for a left coronary angiography in order to simulate mechanical and biological stress in the catheters. Traction tests were performed for the functionality and the integrity was tested through Infrared Spectrometry and Scanning Electronic Microscopy. The study evidenced a tendency to an increase in rigidity at every increment of the reprocessing number (p<0.05). The changes in the mechanical properties and molecular structures of the polymers were more evident as of the fifth reprocessing. Micrographies revealed an increase in rugosity as of the forth reprocessing. The results of this study may contribute to the elaboration of reprocessing protocols and a systematic surveillance of the reutilization of single use materials, not only due to their economical relevance, but especially from the ethical, legal, biological, functional and care point of view.

El objetivo del trabajo fue validar el reprocesamiento de catéteres cardíacos angiográficos en cuanto a sus características de funcionalidad mecánica e integridad molecular y microestructural de la cadena de polímeros. Investigación experimental, aplicada, comparativa y controlada. Se construyó un banco de simulación de una arteriografía de coronaria izquierda para simular un estrés mecánico y biológico en catéteres. Se testeó la funcionalidad por ensayo de tracción y la integridad por Espectroscopía Local Infrarroja y Microscopía Electrónica de Barrido. Se evidenció una tendencia al aumento de la rigidez en cada incremento del número de reprocesamientos (p<0,05). Las modificaciones de las propiedades mecánicas y de las estructuras moleculares de los polímeros fueron más evidentes a partir del quinto reprocesamiento. Las micrografías revelaron un aumento de rugosidad a partir del cuarto reprocesamiento. Los resultados de este estudio podrán contribuir en la elaboración de protocolos de reprocesamiento y vigilancia sistemática de la reutilización de materiales de uso único, no sólo por su relevancia económica, sino también, y sobre todo, respecto del punto de vista ético, legal, biológico, funcional y asistencial.

Objetivou-se validar o reprocessamento de cateteres cardíacos angiográficos quanto às suas características de funcionalidade mecânica e à integridade molecular e micro-estrutural da cadeia polimérica. Pesquisa experimental, aplicada, comparativa e controlada. Construiu-se uma bancada de simulação de uma arteriografia de coronária esquerda para simular um estresse mecânico e biológico em cateteres. Testou-se a funcionalidade por ensaio de tração e a integridade por Espectroscopia na Região do Infravermelho e Microscopia Eletrônica de Varredura. Evidenciou-se uma tendência ao aumento da rigidez a cada acréscimo do número de reprocessamento (p<0,05). As modificações das propriedades mecânicas e das estruturas moleculares dos polímeros foram mais evidentes a partir do quinto reprocessamento. As micrografias revelaram o aumento de rugosidade a partir do quarto reprocessamento. Os resultados deste estudo poderão contribuir para a elaboração de protocolos de reprocessamento e vigilância sistemática da reutilização de materiais de uso único, não apenas por sua relevância econômica, mas sobretudo do ponto de vista ético, legal, biológico, funcional e assistencial.

Objetivou-se validar o reprocessamento de cateteres cardíacos angiográficos quanto às suas características de funcionalidade mecânica e à integridade molecular e micro-estrutural da cadeia polimérica. Pesquisa experimental, aplicada, comparativa e controlada. Construiu-se uma bancada de simulação de uma arteriografia de coronária esquerda para simular um estresse mecânico e biológico em cateteres. Testou-se a funcionalidade por ensaio de tração e a integridade por Espectroscopia na Região do Infravermelho e Microscopia Eletrônica de Varredura. Evidenciou-se uma tendência ao aumento da rigidez a cada acréscimo do número de reprocessamento (p<0,05). As modificações das propriedades mecânicas e das estruturas moleculares dos polímeros foram mais evidentes a partir do quinto reprocessamento. As micrografias revelaram o aumento de rugosidade a partir do quarto reprocessamento. Os resultados deste estudo poderão contribuir para a elaboração de protocolos de reprocessamento e vigilância sistemática da reutilização de materiais de uso único, não apenas por sua relevância econômica, mas sobretudo do ponto de vista ético, legal, biológico, funcional e assistencial.

The objective of this study was to validate the reprocessing of angiographic cardiac catheters regarding their characteristics of mechanical functionality and the molecular and micro-structural integrity of the polymeric chain. This is an experimental, applied, comparative and controlled study. A simulation set was built for a left coronary angiography in order to simulate mechanical and biological stress in the catheters. Traction tests were performed for the functionality and the integrity was tested through Infrared Spectrometry and Scanning Electronic Microscopy. The study evidenced a tendency to an increase in rigidity at every increment of the reprocessing number (p<0.05). The changes in the mechanical properties and molecular structures of the polymers were more evident as of the fifth reprocessing. Micrographies revealed an increase in rugosity as of the forth reprocessing. The results of this study may contribute to the elaboration of reprocessing protocols and a systematic surveillance of the reutilization of single use materials, not only due to their economical relevance, but especially from the ethical, legal, biological, functional and care point of view.

El objetivo del trabajo fue validar el reprocesamiento de catéteres cardíacos angiográficos en cuanto a sus características de funcionalidad mecánica e integridad molecular y microestructural de la cadena de polímeros. Investigación experimental, aplicada, comparativa y controlada. Se construyó un banco de simulación de una arteriografía de coronaria izquierda para simular un estrés mecánico y biológico en catéteres. Se testeó la funcionalidad por ensayo de tracción y la integridad por Espectroscopía Local Infrarroja y Microscopía Electrónica de Barrido. Se evidenció una tendencia al aumento de la rigidez en cada incremento del número de reprocesamientos (p<0,05). Las modificaciones de las propiedades mecánicas y de las estructuras moleculares de los polímeros fueron más evidentes a partir del quinto reprocesamiento. Las micrografías revelaron un aumento de rugosidad a partir del cuarto reprocesamiento. Los resultados de este estudio podrán contribuir en la elaboración de protocolos de reprocesamiento y vigilancia sistemática de la reutilización de materiales de uso único, no sólo por su relevancia económica, sino también, y sobre todo, respecto del punto de vista ético, legal, biológico, funcional y asistencial.

Visando fazer o controle da força de preensão de uma órtese de mão, foi desenvolvido um circuito eletrônico que usa como feedback a corrente elétrica do atuador, um motor de corrente contínua. Verificando-se a ocorrência da sobre-corrente no atuador este é desativado. Essa sobre-corrente é ajustada de acordo com a força de preensão desejada. Experimentos realizados determinaram a força no tendão artificial e conseqüentemente o torque. Como resultado, foi obtido o controle da força de preensão de acordo com uma regulagem no circuito eletrônico. Este trabalho possibilitará maior segurança do usuário e controle do equipamento.

Planning to make the hold force control of one hand' s orthosis, an electronic circuit was developed using the actuator electric current (direct-current motor) as feedback. Verifying the occurrence of over currente in the actuator, it is disactivated. This over chain is regulated in accordance with grip force desired. Carried through experiments the force in the artificial tendons was determined and consequently the torque. As result, the grip force control was gotten in accordance with a regulation in the electronic circuit. This work makes possible greater security for the user and equipment' s control.

Este trabalho determina as relações entre os ângulos das articulações interfalangeanas e metacarpo-falangeanas para os dedos indicador, médio, anular e mínimo da mão humana durante alguns movimentos de pinça com o objetivo de desenvolver uma prótese multifuncional de mão com movimentos antropomórficos. Uma das grandes dificuldades encontradas para o desenvolvimento destas relações é o fato da mão apresentar um elevado número de graus de liberdade, dificultando a análise dos dados. Utiliza-se um sistema de captura de imagem em apenas um plano para analisar o movimento. Determinam-se as relações para os movimentos de flexão e extensão dos dedos, desprezando adução e abdução durante a realização destas pinças.

This works presents the relation for the angles of interphalanges and metacharpo-phalange joints for the index, middle, ring and little finger of human hand. These angles are determinated during a grasp movement. These relations will be used to develop a hand prosthesis with anthropomorphic movements. The main difficult found in this work was the highest numbers of degrees of freedom from the human hand. A methodology was developed to find these angles. This methodology analyzed the movement in 2-D space, and use only one digital camera and a computer. This methodology could be used for determinate these relations for prosthesis because the abduction/adduction movements was almost never applied in this kind of mechanism.