ABSTRACT BACKGROUND: Stroke is a major cause of mortality worldwide. Renal dysfunction is an important risk factor for stroke. Brazilian studies on stroke knowledge are generally population based. Studies stratifying stroke knowledge according to comorbidities are rare. Scientific data are essential to guide the awareness of stroke. OBJECTIVE: To assess stroke knowledge in patients with chronic kidney disease (CKD) on hemodialysis. DESIGN AND SETTING: Cross-sectional analytical study of patients with CKD on hemodialysis in north-eastern Brazil. METHODS: A self-administered questionnaire survey on stroke awareness was administered to patients with CKD on hemodialysis between April and November 2022. The chi-square test and other descriptive statistics were used. Univariate and multivariate analyses were performed using logistic regression. RESULTS: A total of 197 patients were included in the analysis. The Brazilian acronym for stroke was used by 53.5% of the participants. Less than 10.0% of the sample showed optimal decision-making ability regarding stroke. Of the participants, 29.9% knew at least one risk factor and one symptom; however, this was considered as having below the minimum capacity because they did not know the emergency service call number. In the analysis adjusted for income and education, females (odds ratio [OR], 0.40%; 95% confidence interval [CI], 0.20-0.82), older patients (OR, 0.24%; 95% CI, 0.09-0.63) and having at most one comorbidity (OR, 0.48%; 95% CI, 0.23-0.98) were factors for lower levels of knowledge or ideal decision-making capacity against stroke. CONCLUSIONS: Patients on hemodialysis, especially women and older people, have little knowledge about stroke.

SUMMARY OBJECTIVE: The aim of this study was to investigate whether the degree of urbanization influences the prevalence of chronic kidney disease in Brazilian indigenous people. METHODS: This is a cross-sectional study conducted between 2016 and 2017 in northeastern Brazil and includes individuals aged between 30 and 70 years from two specific indigenous groups who volunteered to participate in the study: the Fulni-ô people (lowest degree of urbanization) and the Truká group (greater degree of urbanization). Cultural and geographical parameters were used to characterize and measure the magnitude of urbanization. We excluded individuals with known cardiovascular disease or renal failure who required hemodialysis. Chronic kidney disease was defined as a single measurement of an estimated glomerular filtration rate <60 mL/min/1.73 m2 using the Chronic Kidney Disease Epidemiology Collaboration creatinine equation. RESULTS: A total of 184 indigenous people from the Fulni-ô group and 96 from the Truká group with a median age of 46 years (interquartile range: 15.2) were included. We found a chronic kidney disease rate of 4.3% in the total indigenous population, generally affecting an older population: 41.7% over 60 years old (p<0.001). The Truká people had a chronic kidney disease prevalence of 6.2%, with no differences in kidney dysfunction across age groups. The Fulni-ô participants had a chronic kidney disease prevalence of 3.3%, with a higher proportion of kidney dysfunction in older participants (of the six Fulni-ô indigenous people with chronic kidney disease, five were older). CONCLUSION: Our results suggest that a higher degree of urbanization seems to negatively influence the prevalence of chronic kidney disease in Brazilian indigenous people.

ABSTRACT INTRODUCTION: Smartphone and application use can improve communication and monitoring of chronic diseases, including chronic kidney disease, through self-management and increased adherence to treatment. OBJECTIVE: To assess smartphone use in patients with chronic kidney disease on dialysis and their willingness to use mobile applications as a disease self-management strategy. DESIGN AND SETTING: This was a cross-sectional study of chronic kidney disease patients on hemodialysis in the São Francisco Valley in the Northeast Region, Brazil. METHODS: The questionnaire developed by the authors was administered between April and June 2021. Cronbach's alpha coefficient for the construct was 0.69. Associations between the dependent and independent variables were determined using univariate analysis. Multivariate analysis with logistic regression analysis was also performed. RESULTS: A total of 381 patients were included, of whom 64% had a smartphone, although only 3.1% knew of a kidney disease-related application. However, 59.3% believed that using an application could help them manage their disease. Having a smartphone was associated with treatment adherence, higher educational attainment, and higher per capita income. Educational attainment remained an independent factor in multivariate analysis. CONCLUSION: More than 64% of patients had a smartphone, although few knew of applications developed for kidney disease. More than half of the population believed that technology use could benefit chronic kidney disease treatment. Smartphone ownership was more common among the younger population, with higher educational attainment and income, and was associated with greater adherence to hemodialysis sessions.

Abstract: Introduction: Traditional communities are groups of socially organized individuals with common economic, socio-environmental, and cultural behaviors. Brazil’s indigenous communities are a prime example of these groups, suffering the impact of urbanization, the growth of chronic diseases, epidemics, and increased food insecurity. Experience report: To describe the health team’s experiences in the use of a data management tool for care in an indigenous community in northeastern Brazil. Methodology: This is an experience report on the use of a digital tool to assist actions in a traditional community. The health team was divided into community health agents and medical students. Discussion: The description of the experiences and analysis of the narratives resulted in identifying 258 citations, classified into 12 categories related to the study scope. Of these, issues related to benefits of the tool were the most commonly mentioned (43.41%), where the subgroups addressed different reflections. The second most cited category referred to the tool’s limitations (15.11%), with the need for an internet connection being the critical point. This research, therefore, shows the tool’s advantages in health care but also explains weaknesses inherent to its use, raising important issues of this experience and stimulating similar practices. Conclusion: This experience report, as a scientific method, addresses essential experienced issues related to the practical applicability of a digital tool in an indigenous community. Although it is undeniable that there are obvious points of weakness, these did not compromise the positive result of the experience, and care was improved.

Resumo: Introdução: As comunidades tradicionais são grupos de indivíduos socialmente organizados que partilham comportamentos econômicos, socioambientais e culturais comuns. Entre elas, destacam-se as comunidades indígenas no Brasil, que vêm sofrendo o impacto da urbanização, do crescimento de doenças crônicas e epidemias e do aumento da insegurança alimentar. Relato de experiência: Este estudo teve como objetivo descrever as experiências da equipe de saúde, quanto ao uso de uma ferramenta de gestão de dados na assistência, em uma comunidade indígena no Nordeste brasileiro. Trata-se de um relato de experiência do uso de uma ferramenta digital nas ações assistenciais em uma comunidade tradicional. A equipe de saúde foi dividida em dois grupos: agentes comunitários de saúde e estudantes de Medicina. Discussão: A descrição das experiências e a análise das narrativas resultaram na identificação de 258 citações, que foram classificadas em 12 categorias, relacionadas ao objeto de estudo. Dentre estas, as questões ligadas aos benefícios da ferramenta foram as mais mencionadas (43,41%), em que os subgrupos abordaram diferentes reflexões. A segunda categoria mais citada se referia às limitações da ferramenta (15,11%), sendo a necessidade do sinal de internet o ponto crítico. Ou seja, esta pesquisa mostra vantagens da ferramenta na atenção à saúde, mas também explicita fragilidades inerentes ao seu uso, de modo a trazer questões importantes dessa vivência e estimular práticas semelhantes. Conclusão: Esse relato de experiência, como método científico, traz importantes questões vivenciadas, relacionadas à aplicabilidade prática de uma ferramenta digital em uma comunidade indígena. Apesar de ser inegável que há pontos de fragilidade evidentes, eles não comprometeram o resultado afirmativo da vivência, melhorando a assistência.

ABSTRACT BACKGROUND: Stroke is one of the main causes of death worldwide. Educational interventions on stroke are potentially effective in reducing the period between the onset of symptoms and the initial emergency medical assistance. OBJECTIVES: To assess high school students’ knowledge of stroke. DESIGN AND SETTING: Cross-sectional study conducted in high schools in northeastern Brazil. METHODS: A self-structured questionnaire survey regarding stroke awareness was applied among high school students in northeastern Brazil. Data were collected between 2018 and 2019. The chi-square test and other descriptive statistics were used. Univariate and multivariate analyses were performed using logistic regression. RESULTS: A total of 1,788 students were analyzed. Eighty percent (n = 1430) of them did not have the minimum knowledge on how to act in a stroke situation. Only 10% (n = 179) presented the ideal knowledge on how to act. Males presented lower levels of knowledge on risk factors (odds ratio, OR: 0.62%; 95% confidence interval, CI: 0.49-0.79) and signs and symptoms of stroke (OR: 0.63%; 95% CI: 0.52-0.77). Students with ≥ 10 years of schooling (OR: 1.64%; 95% CI: 1.30-2.07) demonstrated greater knowledge of signs and symptoms of stroke. Students aged 18 years (OR: 1.70%; 95% CI: 1.14-2.52) demonstrated greater knowledge than other ages regarding the telephone number of the emergency medical services. CONCLUSIONS: There was a knowledge deficit with regard to recognizing stroke and activating the emergency medical services. The findings apply to the sample investigated and suggest that there is a need for stroke educational interventions, starting in high school.

ABSTRACT INTRODUCTION: Smartphone and application use can improve communication and monitoring of chronic diseases, including chronic kidney disease, through self-management and increased adherence to treatment. OBJECTIVE: To assess smartphone use in patients with chronic kidney disease on dialysis and their willingness to use mobile applications as a disease self-management strategy. DESIGN AND SETTING: This was a cross-sectional study of chronic kidney disease patients on hemodialysis in the São Francisco Valley in the Northeast Region, Brazil. METHODS: The questionnaire developed by the authors was administered between April and June 2021. Cronbach's alpha coefficient for the construct was 0.69. Associations between the dependent and independent variables were determined using univariate analysis. Multivariate analysis with logistic regression analysis was also performed. RESULTS: A total of 381 patients were included, of whom 64% had a smartphone, although only 3.1% knew of a kidney disease-related application. However, 59.3% believed that using an application could help them manage their disease. Having a smartphone was associated with treatment adherence, higher educational attainment, and higher per capita income. Educational attainment remained an independent factor in multivariate analysis. CONCLUSION: More than 64% of patients had a smartphone, although few knew of applications developed for kidney disease. More than half of the population believed that technology use could benefit chronic kidney disease treatment. Smartphone ownership was more common among the younger population, with higher educational attainment and income, and was associated with greater adherence to hemodialysis sessions.

Resumo Objetivo: Avaliar taxas de sucesso e de complicações de biópsias renais guiadas por ultrassonografia em um hospital terciário. Materiais e Métodos: Análise retrospectiva de 97 biópsias renais realizadas entre 1º de março de 2017 e 31 de outubro de 2019, guiadas por ultrassonografia e executadas por um único médico radiologista. Resultados: Oitenta e sete biópsias apresentaram diagnóstico anatomopatológico definitivo. Cinco biópsias foram inconclusivas (5,4%) e precisaram de um segundo procedimento. Houve complicações em sete procedimentos (7,6%), todas devidamente solucionadas. Conclusão: A biópsia renal guiada por ultrassonografia demonstrou ser um método efetivo e seguro para o diagnóstico de nefropatias, com elevada taxa de sucesso em sua execução.

Abstract Objective: To evaluate the success and complication rates of ultrasound-guided renal biopsy at a tertiary care hospital. Materials and Methods: This was a retrospective analysis of 97 ultrasound-guided renal biopsies, all performed by the same radiologist, between 1 March, 2017 and 31 October, 2019. Results: Of the 97 biopsies evaluated, 87 had a definitive pathological diagnosis. In five cases (5.4%), the biopsy results were inconclusive and a second procedure was required. In seven procedures (7.6%), there were complications, all of which were properly resolved. Conclusion: Ultrasound-guided renal biopsy has proven to be a safe, effective method for the diagnosis of nephropathies, with high success rates.

RESUMO Objetivo: avaliar as características demográficas e clínicas associadas ao desenvolvimento de pneumonia em pacientes após acidente vascular encefálico internados em um hospital terciário do Vale do São Francisco que atende os estados de Pernambuco e Bahia, Brasil. Métodos: trata-se de estudo unicêntrico, observacional, analítico e transversal realizado a partir dos prontuários de pacientes com diagnóstico de acidente vascular encefálico incluídos no Registro de Acidente Vascular Encefálico (Estudo RAVESS). A análise estatística foi composta pelos testes qui-quadrado, exato de Fisher e a análise de variância com pós-teste de Bonferroni com nível de P≤0,05. Resultados: foram coletados dados de 69 pacientes com AVE agudo com média±desvio padrão de idade de 63,2±16,8 anos, sendo 37 (53,6%) do sexo feminino, com prevalência de pneumonia durante o internamento estimada em 31,9% (Intervalo de Confiança de 95%: 21,2-44,2%). Na análise univariada para preditores de pneumonia após acidente vascular encefálico foram identificados: idade mais avançada (72,6±17,9 vs. 58,8±14,5; P=0,001), menor sinal de resposta a escala de coma de Glasgow durante a admissão (11,3±1,8 vs. 13,3±2,1; P=0,001) e maior frequência de disartria na admissão (61,9% vs. 27,9%; P=0,009). Conclusão: a pneumonia foi uma complicação prevalente em pacientes após acidente vascular encefálico de um hospital terciário brasileiro, tendo sido relacionada com idade avançada do paciente e a severidade do evento encefálico.

ABSTRACT Purpose: to assess the demographic and clinical characteristics associated with the development of pneumonia in post-stroke patients hospitalized in a tertiary hospital, located in the Vale do São Francisco, that covers the states of Pernambuco and Bahia, Brazil. Methods: a unicentric, observational, analytical, cross-sectional study, based on the medical records of patients diagnosed with stroke and included in the Stroke Registry (RAVESS study). The statistical analysis was made with the chi-square test, Fisher’s exact test, and the analysis of variance, with the Bonferroni’s post-test, and P≤0.05. Results: data from 69 patients presented with acute stroke were collected, aged 63.2±16.8 years; 37 (53.6%) were females; the prevalence of pneumonia during hospital stay was estimated at 31.9% (95% confidence interval: 21.2-44.2%). In the univariate analysis of predictors for post-stroke pneumonia, the following were identified: older age (72.6±17.9 vs. 58.8±14.5; P = 0.001), lower response signal to the Glasgow Coma Scale at admission (11.3±1.8 vs. 13.3±2.1; P = 0.001), and higher frequency of dysarthria at admission (61.9% vs. 27.9%; P = 0.009). Conclusion: pneumonia was a prevalent complication in post-stroke patients at a Brazilian tertiary hospital. It was related to the patient’s older age and the severity of the cerebral event.

RESUMO Febre de origem indeterminada (FOI) é uma entidade desafiadora com presença marcante nos hospitais de todo o mundo. É definida como temperatura ≥37,8 ° C em várias ocasiões, com duração ≥3 semanas, na ausência de diagnóstico após três dias de investigação hospitalar ou três consultas ambulatoriais. As principais etiologias são de ordem infecciosa, neoplásica e doenças inflamatórias não infecciosas. O diagnóstico é baseado na história clínica e no exame físico minuciosos desses pacientes, com a finalidade de direcionar os exames complementares específicos a serem realizados em cada caso. A abordagem diagnóstica inicial do paciente com FOI deve incluir exames complementares inespecíficos. A terapia empírica não é recomendada (com poucas exceções) em pacientes com febre prolongada, uma vez que ela pode camuflar e retardar o diagnóstico e a conduta para tratar a etiologia específica. O prognóstico engloba uma mortalidade de 12-35%, variando de acordo com a etiologia de base.

SUMMARY Fever of undetermined origin (FUO) is a challenging entity with a striking presence in hospitals around the world. It is defined as temperature ≥ 37.8 ° C on several occasions, lasting ≥ three weeks, in the absence of diagnosis after three days of hospital investigation or 3 outpatient visits. The main etiologies are infectious, neoplastic, and non-infectious inflammatory diseases. The diagnosis is based on the detailed clinical history and physical examination of these patients, in order to direct the specific complementary tests to be performed in each case. The initial diagnostic approach of the FUO patient should include non-specific complementary exams. Empirical therapy is not recommended (with few exceptions) in patients with prolonged fever, as it may disguise and delay the diagnosis and conduct to treat the specific etiology. The prognosis encompasses mortality of 12-35%, varying according to the baseline etiology.

RESUMO Febre de origem indeterminada (FOI) é uma entidade desafiadora com presença marcante nos hospitais de todo o mundo, à qual uma miríade de diagnósticos diferenciais podem estar associados. É definida como temperatura axilar ≥37,8 0 C em várias ocasiões, com duração ≥ três semanas, na ausência de diagnóstico após três dias de investigação hospitalar ou três consultas ambulatoriais. As principais etiologias são de ordem infecciosa, neoplásica e reumatológica. O diagnóstico é baseado na história clínica e no exame físico minuciosos desses pacientes, com a finalidade de direcionar os exames complementares específicos a serem realizados em cada caso. A terapia empírica não é recomendada (com poucas exceções) em pacientes com febre prolongada, uma vez que ela pode camuflar e retardar o diagnóstico e a conduta para tratar a etiologia específica. O prognóstico engloba uma mortalidade de 12–35%, variando de acordo com a etiologia de base. O objetivo deste estudo é revisar os principais tópicos acerca da febre de origem indeterminada, trazendo aspectos históricos e científicos, nacionais e internacionais.

SUMMARY Fever of undetermined origin (FUO) is a challenging entity with a striking presence in hospitals around the world and can be associated with a myriad of differential diagnoses. It is defined as axillary temperature ≥ 37.8 ° C on several occasions, lasting ≥ three weeks, in the absence of diagnosis after three days of hospital investigation or three outpatient visits. The main etiologies are: infectious, neoplastic, and rheumatic. The diagnosis is based on the detailed clinical history and physical examination of these patients, in order to direct the specific complementary tests to be performed in each case. Empirical therapy is not recommended (with few exceptions) in patients with prolonged fever, as it may disguise and delay the diagnosis and conduct to treat the specific etiology. The prognosis encompasses mortality of 12% - 35%, varying according to the underlying etiology. In this sense, the objective of this study is to review the main topics about fever of undetermined origin, bringing historical and scientific aspects, national and international.

Purpose: This paper aims to provide an overall review and assessment of the virtues and flaws of decentralized self-regulated markets, discussing in particular the extent to which deceiving attitudes by some market participants might be potentially diluted and contradicted. Design/methodology/approach: To approach deception and morality in markets, the paper follows two paths. First, the relevant recent literature on the theme is reviewed, examined and debated, and second, one constructs a simulation model equipped with the required elements to discuss the immediate and long-term impacts of deceiving behaviour over market outcomes. Findings: The discussion and the model allow for highlighting the main drivers of the purchasing decisions of consumers and for evaluating how they react to manipulating behaviour by firms in the market. Agents pursuing short-run gains through unfair market practices are likely to be punished as fooled agents spread the word about the malpractices they were allegedly subject to. Research limitations/implications: Markets are complex entities, where large numbers of individual agents typically establish local and direct contact with one another. These agents differ in many respects and interact in unpredictable ways. Assembling a concise model capable of addressing such complexity is a difficult task. The framework proposed in this paper points in the intended direction. Originality/value: The debate in this paper contributes to a stronger perception on the mechanisms that attribute robustness and vitality to markets.

RESUMO Introdução Num cenário de aprendizagem clínica, preceptores devem se comportar como mediadores entre os saberes que o estudante já tem e os que necessita adquirir, integrando a teoria e a prática no contexto da assistência ao paciente. Para isso, é necessário capacitar preceptores e desenvolver instrumentos capazes de aferir o desempenho de tais docentes. Em 2008, foi desenvolvido na Holanda o Maastricht Clinical Teaching Questionnaire (MCTQ), destinado à avaliação de preceptores pelos estudantes com o objetivo de proporcionar feedback a esses sobre suas habilidades de ensino em relação à supervisão realizada durante o estágio. A validação de um instrumento para outro idioma é de grande valia, uma vez que permite avaliar e investigar determinado fenômeno em diferentes países. Objetivo Realizar a validação do MCTQ para a língua portuguesa. Metodologia Trata-se de um estudo de validação de instrumento de pesquisa realizado em quatro hospitais do Nordeste brasileiro com a aplicação da versão adaptada para a língua portuguesa do MCTQ em uma amostra não probabilística composta por 246 estudantes de Medicina do quinto e sexto anos de quatro diferentes instituições de ensino do Estado de Pernambuco. Para avaliar a validade do construto, foi utilizado o índice Kappa. A confiabilidade foi medida por meio do Coeficiente Alfa de Cronbach padronizado. O nível de reprodutibilidade do MCTQ foi calculado pelo teste t de Student para medidas repetidas, comparando valores do teste e do reteste. A pesquisa foi aprovada no Comitê de Ética e Pesquisa da Faculdade Pernambucana de Saúde. Resultados O índice Kappa variou entre 0,527 e 0,710, e o Coeficiente Alfa de Cronbach de 0,77 a 0,954, comprovando bom grau de concordância e de consistência interna do instrumento, respectivamente. Em relação à reprodutibilidade, todos os valores de coeficiente de correlação encontrados foram significativos e de boa magnitude (≥ 0,72). Conclusão A versão em português do MCTQ mostrou-se confiável e válida para uso na língua portuguesa e pode ser útil como instrumento a promover melhorias pedagógicas nos cursos de graduação e pós-graduação, especialmente aqueles relacionados às ciências da saúde.

ABSTRACT Introduction In clinical learning scenarios, preceptors should mediate between the knowledge students already possess and the knowledge they need to acquire, integrating theory and practice into the patient care context. In order to make this possible, we must train preceptors and develop instruments for evaluating their performance as educators. In 2008, the Maastricht Clinical Teaching Questionnaire (MCTQ) was developed in the Netherlands with the purpose of enabling students to evaluate their preceptors, in order to provide preceptors with feedback regarding their teaching skills and the supervision provided by them during the internship period. Validating an instrument that has been translated is important and valuable, because it enables certain phenomena to be evaluated and investigated in different countries. Objective To validate the Portuguese-language version of the MCTQ. Methodology This is an instrument validation study, with research carried out in four different hospitals in the Northeast Region of Brazil. It applied the Portuguese-language version of the MCTQ to a non-probability sample composed of 246 fifth- and sixth-year students of Medicine from four different institutions in the state of Pernambuco. Kappa values were used to evaluate the validity of the construct, and reliability was measured using standardized Cronbach’s alpha coefficient. The reproducibility level of the MCTQ was calculated using the Student’s t-test for repeated measures, comparing test and re-test values. This study was approved by the Human Research Ethics Committee of the Faculdade Pernambucana de Saúde. Results The kappa index was between 0.527 and 0.71, and Cronbach’s alpha coefficient was between 0.77 and 0.954, demonstrating that the instrument has good levels of agreement and internal consistency, respectively. With respect to reproducibility, all coefficient correlation values found were significant and showed good magnitude (≥0.72). Conclusion The Portuguese-language version of the MCTQ proved to be reliable and valid for use in Portuguese-language settings, and can be useful as an instrument for promoting pedagogical improvements in undergraduate and graduate courses, especially in health sciences.

Um modelo macroeconómico envolvendo rigidez de informação é desenvolvido de forma a analisar o comportamento das trajetórias temporais da taxa de inflação e do hiato do produto, quando perturbadas por eventuais choques de política monetária. Em oposição ao que é comum em literatura sobre este assunto, diferentes ritmos de atualização de informação conduzem explicitamente a um cenário de interação entre agentes heterogéneos. Especificamente, consideram-se empresas com diferentes frequências de atualização de informação cujo comportamento implica a emergência de ciclos de atenção de possivelmente longa duração; no seio destes ciclos deduzem-se curvas de Phillips com diferentes formas para cada período temporal. Alterações sistemáticas na forma da relação de oferta agregada são o motor que despoleta uma resposta lenta a choques e a eventual persistência de flutuações cíclicas.

A sticky-information macroeconomic model is developed in order to analyze the behavior of the time trajectories of the inflation rate and of the output gap, when disturbed by eventual monetary policy shocks. In opposition to what is typical in the literature on this subject, different paces on information updating explicitly lead to a setting with interaction among heterogeneous agents. Specifically, we consider firms with different information updating frequencies whose behavior implies the emergence of attentiveness cycles of possibly large lengths; within these cycles we deduct a differently shaped Phillips curve for each time period. Systematic changes on the form of the aggregate supply relation will be the engine that triggers a sluggish response to shocks and the eventual persistence of business fluctuations.

Literatura recente sobre crescimento e desenvolvimento financeiro tem salientado a possibilidade de ciclos económicos endógenos que surgem para determinados valores de um dado multiplicador de crédito. Estes estudos concentram-se em empréstimos dirigidos à actividade produtiva e negligenciam o papel do crédito ao consumo. Neste artigo, considera-se um modelo de crescimento endógeno, onde um agente representativo tem de escolher como afectar o crédito; basicamente, o agente considera uma regra simples de acordo com a qual a fracção de crédito para consumo reage a desvios do rácio consumo - riqueza relativamente ao correspondente nível de equilíbrio. Este ambiente gera dinâmica não linear, a qual é analisada localmente e globalmente.

Recent literature on financial development and growth has highlighted the possibility of endogenous business cycles arising for particular levels of a given credit multiplier. These studies concentrate on loans directed to the productive activity and neglect the role of credit to consumption. In this paper, we consider an endogenous growth model, where a representative agent must choose how to allocate credit; basically, the agent considers a simple rule where the share of credit to consumption reacts to deviations of the consumption - wealth ratio relatively to the corresponding steady state level. The setup generates nonlinear dynamics, which are analyzed both locally and globally.

O conceito de racionalidade é uma das noções que mais tem sido alvo de debate e controvérsia no seio da ciência económica. O paradigma da escolha racional, que envolve os comportamentos de maximização do lucro das empresas e de maximização da utilidade das famílias, pode ser posto em causa por um importante número de reflexões que recordam que o processo de escolha humana não é isento de erros, não ignora factores emocionais nem se concretiza fora de um contexto social onde a interacção com terceiros determina comportamentos. O presente texto procura caracterizar o modo como os economistas têm trabalhado a noção de decisão racional e aplica algumas das suas ideias para modelizar o processo de decisão. Em particular, constrói-se um exercício no qual se destacam os custos cognitivos envolvidos no processo de escolha e recorre-se à teoria da escolha discreta para exemplificar como a interacção social e estímulos como a publicidade determinam trajectórias de consumo e utilidade.

The concept of rationality is one of the most debated and controversial notions that the economic science has to offer. The rational choice paradigm, which involves profit maximization and utility maximization behavior, may be questioned by an important number of studies that remind that the human choice process is not an error exempt process, that it does not ignore emotional factors and that it is not fulfilled outside a social context where interaction determines behavior. This text intends to characterize the way in which the economists work the notion of rational decision and applies some of their ideas to model the decision process. In particular, we build an exercise in which one considers the cognitive costs involved in the choice process and we make use of the discrete choice theory to exemplify how social interaction and stimuli like advertising determine consumption and utility trajectories.