871 resultados para Concordância


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Breast cancer is the second type of cancer that affects more women of reproductive age in Brazil. Surgical treatments include: conserving surgery or mastectomy. Aimed to evaluate body image of women undergoing breast cancer surgery, based on the scale Body Image After Breast Cancer Questionnaire. It is a descriptive, exploratory, transversal, with a quantitative approach. Data were collected in Norte-riograndense League Against Cancer, between the months from March to May 2015, after consideration of the Research Ethics Committee of that institution CAEE 35155714.1.0000.5293. The study population consisted of women undergoing breast onco-surgery. To calculate the sample considered the finite population, totaling 120 subjects, collected four guys the most. Data were analyzed by the software Statistical Package for Social Sciences version 20.0. The domain scores of the scale were evaluated using descriptive and inferential statistics. The surgical group mastectomy without reconstruction showed greater impairment of body image in the field "vulnerability", "Care for the body" and "transparency" in relation to other surgical types, and suggests susceptibility to cancer, body appearance and worry that disturb other. The Kruskal-Wallis test showed greater dissatisfaction with body image in the fields "body Stigma" and "transparency" to the radical neoplastic surgery over other surgical types. Dissatisfaction with body image and physical appearance was detected in this study in all six image fields present in scale, with emphasis on the "body Stigma" and "Transparency". This means that the body image disorder is formulated based on the perception of others about themselves and not by perception "self", which justifies the concern with appearance, with body and hide the consequences stemmed cancer. It is expected that the data obtained from the evaluation of body image presented in this study contribute to enable the assistance to oncocirurgiada woman breast integral, essential for the practice of Nursing.

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Tratar-se-á de um estudo metodológico, com abordagem quantitativa; baseado no referencial metodológico da técnica Delphi, com objetivo de construir e validar um protocolo clínico para assistência do enfermeiro ao paciente séptico na Unidade de Terapia Intensiva. A proposta metodológica seguiu duas etapas: elaboração do instrumento por meio da revisão integrativa da literatura e validação de conteúdo do protocolo. O estudo foi aprovado pelo Comitê de Ética em Pesquisa, mediante o Parecer CAAE 41873314.5.0000.5537. O universo amostral foi composto por profissionais enfermeiros, considerados peritos, doutores ou mestres na área da saúde, com experiência em alta complexidade e/ ou estudos de validação de instrumento/protocolo, selecionados por meio da Plataforma Lattes. Referente à primeira etapa elaborou-se um instrumento composto pela caracterização profissional dos peritos; e baseado em evidência científica e nas diretrizes do Surviving Sepsis Campaign, contemplando três tópicos assistenciais ao paciente com sepse, a saber: Triagem para Sepse- Reconhecimento das Manifestações Clínicas; Pacote de Ressuscitação Inicial (Controle das Primeiras 6 Horas); Tratamento de Suporte. A segunda etapa caracterizou-se na validação de conteúdo do instrumento para elaboração final do protocolo, utilizando à técnica Delphi, em duas fases. No que concernem as variáveis referentes ao estudo, na 1ª fase de Delphi, 34 peritos avaliaram o instrumento composto por 18 itens, no período de maio a julho de 2015, e os dados foram analisados pela estatística descritiva (frequência, média, mediana e desvio padrão) e pelo Índice de Validade de Conteúdo (IVC), demonstrando um IVC extremamente satisfatório para 15 itens, com total de 0,79, obtendo assim, a reformulação e refinamento do conteúdo do instrumento. Na segunda fase de Delphi, entre julho e agosto de 2015, participaram 26 peritos, e utilizou-se o percentual de concordância acima de 75% para as variáveis consideradas pertinentes ao protocolo de cuidados ao paciente séptico em UTI, obtendo nesta fase, o percentual de concordância de 95%. O protocolo foi concluído com 15 itens, sendo respaldado e modificado, baseado em evidência científica, nas diretrizes internacionais e nas sugestões dos peritos. A utilização do protocolo proposto poderá contribuir para a prática clínica do enfermeiro ao paciente séptico na Unidade de Terapia Intensiva.

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Tratar-se-á de um estudo metodológico, com abordagem quantitativa; baseado no referencial metodológico da técnica Delphi, com objetivo de construir e validar um protocolo clínico para assistência do enfermeiro ao paciente séptico na Unidade de Terapia Intensiva. A proposta metodológica seguiu duas etapas: elaboração do instrumento por meio da revisão integrativa da literatura e validação de conteúdo do protocolo. O estudo foi aprovado pelo Comitê de Ética em Pesquisa, mediante o Parecer CAAE 41873314.5.0000.5537. O universo amostral foi composto por profissionais enfermeiros, considerados peritos, doutores ou mestres na área da saúde, com experiência em alta complexidade e/ ou estudos de validação de instrumento/protocolo, selecionados por meio da Plataforma Lattes. Referente à primeira etapa elaborou-se um instrumento composto pela caracterização profissional dos peritos; e baseado em evidência científica e nas diretrizes do Surviving Sepsis Campaign, contemplando três tópicos assistenciais ao paciente com sepse, a saber: Triagem para Sepse- Reconhecimento das Manifestações Clínicas; Pacote de Ressuscitação Inicial (Controle das Primeiras 6 Horas); Tratamento de Suporte. A segunda etapa caracterizou-se na validação de conteúdo do instrumento para elaboração final do protocolo, utilizando à técnica Delphi, em duas fases. No que concernem as variáveis referentes ao estudo, na 1ª fase de Delphi, 34 peritos avaliaram o instrumento composto por 18 itens, no período de maio a julho de 2015, e os dados foram analisados pela estatística descritiva (frequência, média, mediana e desvio padrão) e pelo Índice de Validade de Conteúdo (IVC), demonstrando um IVC extremamente satisfatório para 15 itens, com total de 0,79, obtendo assim, a reformulação e refinamento do conteúdo do instrumento. Na segunda fase de Delphi, entre julho e agosto de 2015, participaram 26 peritos, e utilizou-se o percentual de concordância acima de 75% para as variáveis consideradas pertinentes ao protocolo de cuidados ao paciente séptico em UTI, obtendo nesta fase, o percentual de concordância de 95%. O protocolo foi concluído com 15 itens, sendo respaldado e modificado, baseado em evidência científica, nas diretrizes internacionais e nas sugestões dos peritos. A utilização do protocolo proposto poderá contribuir para a prática clínica do enfermeiro ao paciente séptico na Unidade de Terapia Intensiva.

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The study aims to analyze the content and measures of accuracy of the nursing diagnosis Ineffective Self Health in patients undergoing hemodialysis. Study of nursing diagnosis validation carried out in two stages, namely: content analysis by judges and accuracy of clinical indicators. In the first stage, 22 judges evaluated the setting and location of the diagnosis, clinical indicators and etiological factors and their conceptual and empirical definitions. We used the binomial test to determine the proportion of the judges of the relevance of the components of the nursing diagnosis. In the second stage, we used the Latent Class Analysis for the diagnostic accuracy by evaluating 200 patients in a hemodialysis clinic in northeastern Brazil. Research approved by the Ethics Committee, under the Opinion No 387 837 and CAAE 18486413.0.0000.5537. The results show that the judges evaluated as pertinent clinical indicators 12 and 22 etiological factors. Proposed amendment of the nomenclature of five indicators and six factors and the implementation of a clinical indicator for etiology and three etiological factors for clinical indicators. In conceptual and empirical definitions, judges judged as not relevant the conceptual and empirical definitions of a clinical indicator, the conceptual definitions of two etiological factors and empirical definitions four etiological factors. Still, changes were suggested in the conceptual and empirical definitions of two clinical indicators, the conceptual definitions of 12 etiological factors and empirical definitions of 11 etiological factors. Clinical indicators analyzed in the first stage were validated clinically in patients undergoing hemodialysis. The most frequent clinical indicators were Changes in laboratory tests (100%) and daily life choices ineffective to achieve health goals (81%); and three etiological factors had a higher frequency, they are: unfavorable demographic factors (94.5%), beliefs (79%) and comorbidities (77.5%). From Latent class analysis, diagnosis prevalence was estimated at 66.28%. Clinical indicators that showed the best sensitivity measures for the nursing diagnosis Ineffective Self Health were: daily life choices ineffective to achieve health goals and Expression of difficulty with prescribed regimens. In turn, the clinical indicators of inappropriate medication use, no expression of desire to control the disease, irregular attendance to the dialysis sessions and infection were more specific as to that diagnosis. Non-adherence to treatment was the only indicator that showed confidence intervals with values for sensitivity and specificity, statistically above 0.5, being the one who has better diagnostic accuracy as the inference of the nursing diagnosis Ineffective Self Health in hemodialysis clientele. Thus, it is believed that the improvement of the components of diagnosis in question will contribute to the development of more reliable nursing interventions to the health status of the individual in hemodialysis, providing a more scientifically qualified care.

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The study aims to analyze the content and measures of accuracy of the nursing diagnosis Ineffective Self Health in patients undergoing hemodialysis. Study of nursing diagnosis validation carried out in two stages, namely: content analysis by judges and accuracy of clinical indicators. In the first stage, 22 judges evaluated the setting and location of the diagnosis, clinical indicators and etiological factors and their conceptual and empirical definitions. We used the binomial test to determine the proportion of the judges of the relevance of the components of the nursing diagnosis. In the second stage, we used the Latent Class Analysis for the diagnostic accuracy by evaluating 200 patients in a hemodialysis clinic in northeastern Brazil. Research approved by the Ethics Committee, under the Opinion No 387 837 and CAAE 18486413.0.0000.5537. The results show that the judges evaluated as pertinent clinical indicators 12 and 22 etiological factors. Proposed amendment of the nomenclature of five indicators and six factors and the implementation of a clinical indicator for etiology and three etiological factors for clinical indicators. In conceptual and empirical definitions, judges judged as not relevant the conceptual and empirical definitions of a clinical indicator, the conceptual definitions of two etiological factors and empirical definitions four etiological factors. Still, changes were suggested in the conceptual and empirical definitions of two clinical indicators, the conceptual definitions of 12 etiological factors and empirical definitions of 11 etiological factors. Clinical indicators analyzed in the first stage were validated clinically in patients undergoing hemodialysis. The most frequent clinical indicators were Changes in laboratory tests (100%) and daily life choices ineffective to achieve health goals (81%); and three etiological factors had a higher frequency, they are: unfavorable demographic factors (94.5%), beliefs (79%) and comorbidities (77.5%). From Latent class analysis, diagnosis prevalence was estimated at 66.28%. Clinical indicators that showed the best sensitivity measures for the nursing diagnosis Ineffective Self Health were: daily life choices ineffective to achieve health goals and Expression of difficulty with prescribed regimens. In turn, the clinical indicators of inappropriate medication use, no expression of desire to control the disease, irregular attendance to the dialysis sessions and infection were more specific as to that diagnosis. Non-adherence to treatment was the only indicator that showed confidence intervals with values for sensitivity and specificity, statistically above 0.5, being the one who has better diagnostic accuracy as the inference of the nursing diagnosis Ineffective Self Health in hemodialysis clientele. Thus, it is believed that the improvement of the components of diagnosis in question will contribute to the development of more reliable nursing interventions to the health status of the individual in hemodialysis, providing a more scientifically qualified care.

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The Benzylpenicillin (PENG) have been as the active ingredient in veterinary medicinal products, to increase productivity, due to its therapeutic properties. However, one of unfortunate quality and used indiscriminately, resulting in residues in foods exposed to human consumption, especially in milk that is essential to the diet of children and the ageing. Thus, it is indispensable to develop new methods able to detect this waste food, at levels that are toxic to human health, in order to contribute to the food security of consumers and collaborate with regulatory agencies in an efficient inspection. In this work, were developed methods for the quality control of veterinary drugs based on Benzylpenicillin (PENG) that are used in livestock production. Additionally, were validated methodologies for identifying and quantifying the antibiotic residues in milk bovine and caprine. For this, the analytical control was performed two steps. At first, the groups of samples of medicinal products I, II, III, IV and V, individually, were characterized by medium infrared spectroscopy (4000 – 600 cm-1). Besides, 37 samples, distributed in these groups, were analyzed by spectroscopy in the ultraviolet and near infrared region (UV VIS NIR) and Ultra Fast Liquid Chromatograph coupled to linear arrangement photodiodes (UFLC-DAD). The results of the characterization indicated similarities, between PENG and reference standard samples, primarily in regions of 1818 to 1724 cm-1 of ν C=O that shows primary amides features of PENG. The method by UFLC-DAD presented R on 0.9991. LOD of 7.384 × 10-4 μg mL-1. LOQ of 2.049 × 10-3 μg mL-1. The analysis shows that 62.16% the samples presented purity ≥ 81.21%. The method by spectroscopy in the UV VIS NIR presented medium error ≤ 8 – 12% between the reference and experimental criteria, indicating is a secure choice for rapid determination of PENG. In the second stage, was acquiring a method for the extraction and isolation of PENG by the addition of buffer McIlvaine, used for precipitation of proteins total, at pH 4.0. The results showed excellent recovery values PENG, being close to 92.05% of samples of bovine milk (method 1). While samples of milk goats (method 2) the recovery of PENG were 95.83%. The methods for UFLC-DAD have been validated in accordance with the maximum residue limit (LMR) of 4 μg Kg-1 standardized by CAC/GL16. Validation of the method 1 indicated R by 0.9975. LOD of 7.246 × 10-4 μg mL-1. LOQ de 2.196 × 10-3 μg mL-1. The application of the method 1 showed that 12% the samples presented concentration of residues of PENG > LMR. The method 2 indicated R by 0.9995. LOD 8.251 × 10-4 μg mL-1. LOQ de 2.5270 × 10-3 μg mL-1. The application of the method showed that 15% of the samples were above the tolerable. The comparative analysis between the methods pointed better validation for LCP samples, because the reduction of the matrix effect, on this account the tcalculs < ttable, caused by the increase of recovery of the PENG. In this mode, all the operations developed to deliver simplicity, speed, selectivity, reduced analysis time and reagent use and toxic solvents, particularly if compared to the established methodologies.

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The Benzylpenicillin (PENG) have been as the active ingredient in veterinary medicinal products, to increase productivity, due to its therapeutic properties. However, one of unfortunate quality and used indiscriminately, resulting in residues in foods exposed to human consumption, especially in milk that is essential to the diet of children and the ageing. Thus, it is indispensable to develop new methods able to detect this waste food, at levels that are toxic to human health, in order to contribute to the food security of consumers and collaborate with regulatory agencies in an efficient inspection. In this work, were developed methods for the quality control of veterinary drugs based on Benzylpenicillin (PENG) that are used in livestock production. Additionally, were validated methodologies for identifying and quantifying the antibiotic residues in milk bovine and caprine. For this, the analytical control was performed two steps. At first, the groups of samples of medicinal products I, II, III, IV and V, individually, were characterized by medium infrared spectroscopy (4000 – 600 cm-1). Besides, 37 samples, distributed in these groups, were analyzed by spectroscopy in the ultraviolet and near infrared region (UV VIS NIR) and Ultra Fast Liquid Chromatograph coupled to linear arrangement photodiodes (UFLC-DAD). The results of the characterization indicated similarities, between PENG and reference standard samples, primarily in regions of 1818 to 1724 cm-1 of ν C=O that shows primary amides features of PENG. The method by UFLC-DAD presented R on 0.9991. LOD of 7.384 × 10-4 μg mL-1. LOQ of 2.049 × 10-3 μg mL-1. The analysis shows that 62.16% the samples presented purity ≥ 81.21%. The method by spectroscopy in the UV VIS NIR presented medium error ≤ 8 – 12% between the reference and experimental criteria, indicating is a secure choice for rapid determination of PENG. In the second stage, was acquiring a method for the extraction and isolation of PENG by the addition of buffer McIlvaine, used for precipitation of proteins total, at pH 4.0. The results showed excellent recovery values PENG, being close to 92.05% of samples of bovine milk (method 1). While samples of milk goats (method 2) the recovery of PENG were 95.83%. The methods for UFLC-DAD have been validated in accordance with the maximum residue limit (LMR) of 4 μg Kg-1 standardized by CAC/GL16. Validation of the method 1 indicated R by 0.9975. LOD of 7.246 × 10-4 μg mL-1. LOQ de 2.196 × 10-3 μg mL-1. The application of the method 1 showed that 12% the samples presented concentration of residues of PENG > LMR. The method 2 indicated R by 0.9995. LOD 8.251 × 10-4 μg mL-1. LOQ de 2.5270 × 10-3 μg mL-1. The application of the method showed that 15% of the samples were above the tolerable. The comparative analysis between the methods pointed better validation for LCP samples, because the reduction of the matrix effect, on this account the tcalculs < ttable, caused by the increase of recovery of the PENG. In this mode, all the operations developed to deliver simplicity, speed, selectivity, reduced analysis time and reagent use and toxic solvents, particularly if compared to the established methodologies.

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Technological advances combined with healthcare assistance bring increased risks related to patient safety, causing health institutions to be environments susceptible to losses in the provided care. Sectors of high complexity, such as Intensive Care Units have such characteristics highlighted due to being spaces designed for the care of patients in serious medical condition, when the use of advanced technological devices becomes a necessity. Thus, the aim of this study was to assess nursing care from the perspective of patient safety in intensive care units. This is an evaluative research, which combines various forms of data collection and analysis in order to conduct a deepened investigation. Data collection occurred in loco, from April to July 2014 in hospitals equipped with adult intensive care unit services. For this, a checklist instrument and semi-structured interviews conducted with patients, families, professionals were used in order to evaluate the structure-process-outcome triad. The instrument for nursing care assessment regarding Patient Safety included 97 questions related to structure and processes. Interviews provided data for outcome analysis. The selection of interviewees/participants was based on the willingness of potential participants. The following methods were used to collect data resulting from the instrument: statistical analysis of inter-rater reliability measure known as kappa (K); observations from judges resulting from the observation process; and added information obtained from the literature on the thematic. Data analysis from the interviews was carried out with IRAMUTEQ software, which used Descending Hierarchical Classification and Similarity analysis to aid in data interpretation. Research steps followed the ethical principles presented by Resolution No. 466 of December 12, 2012, and the results were presented in three manuscripts: 1) Evaluation of patient safety in Intensive Care Units: a focus on structure; 2) Health evaluation processes: a nursing care perspective on patient safety; 3) Patient safety in intensive care units: perception of nurses, family members and patients. The first article, related to the structure, refers to the use of 24 items of the employed instrument, showing that most of the findings were not aligned with the adequacy standards, which indicates poor conditions in structures offered in health services. The second article provides an analysis of the pillar of Processes, with the use of 73 items of the instrument, showing that 50 items did not meet the required standards for safe handling due to the absence of adequate scientific guidance and effective communication in nursing care process. For the third article, results indicate that intensive care units were safe places, yet urges for changes, especially in the physical structure and availability of materials and communication among professionals, patients and families. Therefore, our findings suggest that the nursing care being provided in the evaluated intensive care units contains troubling shortcomings with regards to patient safety, thereby evidencing an insecure setting for the assistance offered, in addition to a need for urgent measures to remedy the identified inadequacies with appropriate structures and implement protocols and care guidelines in order to consolidate an environment more favorable to patient safety.

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Actinic cheilitis (AC) is a potentially malignant disorder which affects the lip vermilion and results from chronic exposure to sunlight. Currently, it is not possible to predict which cases of AC may progress to squamous cell carcinoma, and therefore, some biomolecular markers have been researched. Cyclooxygenase 2 (COX-2) is an enzyme associated with inflammatory response which is overexpressed in oral cancer; however, little is known about the role of this protein in actinic cheilitis. About the treatment of this lesion, currently available therapeutic modalities to AC may cause cytotoxic effects and deleterious results to patients. Therefore, the aim of this study was to evaluate the immunoexpression of COX-2 in AC of different risks of malignant transformation and analyse, through clinical follow-up, the efficacy of diclofenac sodium 3% gel in the treatment of this condition. Epithelial immunoexpression of COX-2 was analysed semi-quantitatively in 90 cases of AC classified as low risk (n = 55) and high risk (n = 35) of malignant transformation, in which the scores were assigned: (0) 0 to 5% of positive cells - Negative; (1) 6 to 30% of positive cells - Low expression; (2) 31 to 100% of positive cells - High expression. The chi-square test of Pearson was conducted to verify possible associations between immunoexpression of COX-2 and histologic grade of actinic cheilitis. The weighted kappa coefficient denoted a good interobserver agreement (0.677). Nineteen patients diagnosed with AC were instructed to perform topical application of the gel three times a day for a period of 90 days. In each biweekly visit, a follow-up record was accomplished through digital photographs and after treatment was completed, two researchers analysed all the images to assess clinical aspects of the lip. Furthermore, tolerability to the drug and patient satisfaction after treatment were evaluated. COX-2 was overexpressed in 74.4% of AC cases. Both low and high-risk groups revealed predominance of score 3, followed by scores 2 and 1. There was no significant association (p = 0.315) between COX-2 expression and histological grading. Among the total number of participants of this clinical study, ten showed total remission of all clinical features of the lesion and three had partial improvement of these characteristics. One participant presented worsening of the clinical condition. In five cases, the treatment was discontinued due to development of mild adverse effects at the site of gel application. Regarding analysis of satisfaction and tolerability to the drug, most patients were fully satisfied with the therapy (n = 11) and reported that the drug was not irritating to the lips (n = 9). Our study demonstrates that high expression of COX-2 is common in AC; however, this protein was not associated with malignant transformation risk of the analysed cases. Topical application of diclofenac sodium 3% gel provided a convenient and well tolerated approach in most cases, and may be a promising alternative for the treatment of actinic cheilitis.

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Contamination of groundwater by BTX has been featured in recent decades. This type of contamination is due to small and continuous leaks at gas stations, causing serious problems to public health and the environment. Based on these antecedents, the search for new alternatives for treating contaminated water is shown to be essential. Therefore, this study aimed to evaluate the efficiency of removal of BTX by adsorption processes employing commercial alumina (Al2O3) and alumina supported with iron (Fe/Al2O3) as adsorbents. It was prepared by a in a synthetic gasoline solution and distilled water to simulate an actual sample. Initially, the adsorbents were characterized by techniques XRD, TG / DTG, XRF, FTIR and SEM/EDS, several trials, where he was placed synthetic solution to react in the presence of Al2O3 and Fe/Al2O3 in a closed, mechanical stirring system were performed varying the catalyst concentration 2, 4 and 6 g.L-1 every 0, 10, 30 60, 90 and 120 min, aliquots were taken and brought to analysis by gas chromatography flame ionization with headspace extraction. The results indicated that the absorbent which has higher BTX removal capacity was the Fe/Al2O3 at a concentration of 6 g.L-1, pH = 4 and time of 90 minutes reaction, resulting in an efficiency, resulting in a 86,5% efficiency for benzene removal, for the 95,4% toluene, 90,8% for ɱ,ρ- xylene and 93.7% for the θ-xylenes. Subsequently, we performed a kinetic study of the reactions, the values of experimental adsorption capacity (qe) showed agreement with the values of the theoretical adsorption capacity (qc) to the pseudo-second-order model in the adsorption tests using 2 and 6 gL-1 of Al2O3 and assays using 2, 4 and 6 g.L-1 of Fe/Al2O3. A fact corroborated by the R2 values, thus indicating that the chemical interactions are present in the adsorption mechanisms of BTX.

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This work aims to propose a new model of metasurface with simplified basic cell, able to convert linearly polarized signals generated by planar antenna array in circularly polarized signals, for the ISM frequency band (2.45 GHz), with good bandwidth of return loss and axial ratio. To study the behavior of the proposed structure, the metasurface is coupled to three different structures. First, initial tests are made with the metasurface coupled to a microstrip antenna in its simple configuration. Then the metasurface is coupled to an array with two elements of patch type. And later it is coupled to an optimized array, that uses a stub in its main feed, to get a better impedance matching. The structures are analyzed numerically through Ansoft HFSS™, and to validate these results, the structures are characterized experimentally. The characteristics of transmissions simulated and measures are presented. A good agreement between simulated and measured results was obtained. The structure proposed here has the advantage of meeting the desired characteristics, with a simple geometry to be built using a low-cost substrate (FR-4).

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This work aims to propose a new model of metasurface with simplified basic cell, able to convert linearly polarized signals generated by planar antenna array in circularly polarized signals, for the ISM frequency band (2.45 GHz), with good bandwidth of return loss and axial ratio. To study the behavior of the proposed structure, the metasurface is coupled to three different structures. First, initial tests are made with the metasurface coupled to a microstrip antenna in its simple configuration. Then the metasurface is coupled to an array with two elements of patch type. And later it is coupled to an optimized array, that uses a stub in its main feed, to get a better impedance matching. The structures are analyzed numerically through Ansoft HFSS™, and to validate these results, the structures are characterized experimentally. The characteristics of transmissions simulated and measures are presented. A good agreement between simulated and measured results was obtained. The structure proposed here has the advantage of meeting the desired characteristics, with a simple geometry to be built using a low-cost substrate (FR-4).

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Data variability analysis has been the focus of a number of studies seeking to capture differences of patterns generated by biological systems. Although several studies related to gait employ the analysis of variability in their observations, we noticed a lack of such information for subjects with unilateral coxarthrosis undergoing total hip arthroplasty (THA). To tackle this deficiency of information, we conducted a study of the gait on a treadmill with10 healthy subjects (30.7 ± 6.75 years old) from G1 and 24 subjects (65 ± 8.5 years old) with unilateral THA from G2. Thus, by means of two inertial measurement units (IMUs) positioned in the pelvis, we have developed a detection method of the step and stride for calculating these intervals and extract the signal characteristics. The variability analysis (coefficient of variation) was performed, taking into consideration the extracted features and the step and stride times. The average and the 95% confidence interval estimate for the average of the step and stride times to each group were in agreement with literature. The mean coefficient of variation for the step and stride times was calculated and compared among groups by the Kruskal-Wallis test with 95% confidence interval. Each component X, Y and Z of the two IMUs (accelerometer, magnetometer and gyroscope) corresponded to a variable. The resultants of each sensor, the linear velocity (accelerometers) and the instantaneous angular displacement (gyroscopes) completed the set of variables. The characteristics were extracted from the signals of these variables to check the variability in the G1 and G2 groups . There were significant differences (p <0.05) between G1 and G2 for the average of the step and stride times. The variability of the step and stride, as well as the variability of all other evaluated characteristics were higher for the group G2 (p <0.05). The method proposed in this study proved to be suitable for the measuring of variability of biomechanical parameters related to the extracted features. All the extracted features categorized the groups. The G2 group showed greater variability, so it is possible that the age and the pathological condition of the hip both contributed to this result.

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Due to the growing use of social networks people no longer just consume data, they also produce and share it. Geo-tagged information, i.e., data with geographical location, have been used in many attempts to identify popular places and help tourists that will visit unfamiliar cities. This Master Thesis presents an online strategy that uses geo-tagged photos and their metadata in order to identify places of interest inside a given geographical area and retrieve relevant related information. The whole process runs automatically in real time, returning updated information about places. The proposed strategy takes into account the inherent dynamism of social media, and thus is robust under inconsistencies and/or outdated information, a common issue in solutions that rely on previously stored data. The analysis of the results showed that our approach is very promising, returning places that present high agreement with those from a popular travel website.

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This work presents an experimental investigation of thermal hydraulic performance of the nanofluid composed by graphene nanoparticles dispersed in a mixture of water and ethylene glycol at a ratio of 70:30% by volume. The tests were carried out under forced convection inside a circular tube with uniform heat flux on the wall for the laminar-turbulent transition regime. The mass flow rate ranged from 40 to 70 g/s corresponding to Reynolds numbers between 3000 and 7500. The heat flux was maintained constant at values of 11, 16 and 21 kW/m², as well as the inlet temperature of 15, 20 and 25°C. Three samples were produced with the nanofluid volumetric concentration of 0.05%, 0.10% and 0.15%. Thermophysical properties were experimentaly measured for all samples that were critically compared and discussed with theoretical models most commonly used in the literature. Initially, experiments with distilled water confirmed the validity of the experimental equipment for the thermo-hydraulic tests. Therefore, nanofluid samples that showed the highest thermal conductivity, corresponding to the volumetric concentrations of 0.15% and 0.10%, were subjected to the tests. The thermal-hydraulic performance for both samples was unsatisfactory. The heat transfer coefficients for convection of nanofluids reduced 21% in average, for the sample with = 0.15% and 26% and for =0.10%. The pressure drop of the samples was higher than the base fluid. Finally, the pressure drop and heat transfer coefficient by convection of both samples were also compared to theoretical models. The models used for pressure drop showed an excellent agreement with experimental results, which is remarkable considering the transitional flow.