Abstract The intrauterine device is the most used long-acting reversible contraceptive method, presenting a low incidence of complications. The authors present a case of an intrauterine device migration, with an uterine perforation by its lower extremity.

Resumo O dispositivo intrauterino é o método contracetivo reversível de longa duração mais utilizado, apresentando uma baixa incidência de complicações. Os autores apresentam um caso de migração de um dispositivo intrauterino, em que se verificou perfuração uterina a partir da sua extremidade inferior.

We examine the analytical theories of heat developed by Laplace, Poisson and Carnot, and the thermodynamic theories based on the energy conservation and the principle of the increase of entropy formulated by Clausius. We present an analysis of the approaches developed by Maxwell, Gibbs, Planck, Duhem, Nernst, and De Donder as well as the irreversible thermodynamics of Prigogine, and the theory of liquid gas transition of van der Waals. We show that the thermodynamic potentials dominated the development of the theory of thermodynamics since Gibbs. They were introduced by Massieu under the name of characteristic functions and were demonstrated by Gibbs to have the suitable properties to characterize equilibrium of systems with variable composition, and to hold the convexity properties. We also show that the thermodynamic potentials were the relevant quantity in the Duhem approach to thermodynamics and to thermochemistry.

We examine the concept of probability from its emergence within the realm of the games of chance and the development of the theory of probability until the appearance of the treatise of Kolmogorov on this subject. The discipline related to that theory is framed as the science of aleatory events. Probability is understood as a primitive concept represented by a measure assigned to the space of events and obeying the fundamental postulates of the theory. The measurement of probability is the ratio of the number of the observed favorable outcomes and the total number of observed outcomes when these numbers are larger enough.

We examine the metaphysical theories of motion and matter developed by Democritus, Plato, and Aristotle, as well as other theories that appeared later on and were great influenced by Aristotle. We distinguish two subsequent developments. One is the impetus theory for the projectile motion and the other is the void theory for the rise of liquids by suction. We analyze the Galileo theory of motion, emphasizing the crucial step in its development which was the precise definition of velocity. We also analyze the events related to the experiments of Torricelli, which was understood as the production of void, and his explanation based on the weight of the atmospheric air.

RESUMO Influência da altitude e sazonalidade na riqueza de espécies e densidade de ninhos de cupins em um ambiente de serra da Caatinga Brasileira. As variações na altitude modulam a riqueza e densidade de espécies em ecossistemas tropicais. A densidade e riqueza de cupins são influenciadas por variações na temperatura, umidade, e propriedades do solo de acordo com a elevação da altitude. Isso é bem conhecido para florestas úmidas, e pouca informação é encontrada para áreas semiáridas do Brasil. Neste estudo, tivemos por objetivo identificar a riqueza de espécies e densidade de encontros de cupins em uma serra localizada em floresta brasileira de Caatinga. Encontramos variação na composição de espécies em função da altitude (em comparação de topo e base da serra), e em períodos de seca e chuva, com aumento na estação chuvosa. O aumento na diversidade nesse período e nas elevações da altitude pode ser explicada pelo aumento na umidade após as chuvas, e a manutenção da temperatura propiciada pelas condições do topo da serra. Nossos dados fornecem informações importantes a respeito da diversidade de cupins no semiárido em função de elevações na altitude, e contribui com outros estudos que expandem o nosso conhecimento a respeito de como a elevação pode afetar esses organismos.

ABSTRACT The variation in altitude drives the richness and density of species in tropical ecosystems. The diversity and richness of termites are influenced by the variations in temperature, humidity, and soil properties according to altitude elevation. This is well known for rainy forests and little information is found for semiarid areas of Brazil. In this study, we aimed to identify species richness and encounters density of termites in a hill inserted in the Caatinga Brazilian forest. We found variation in the composition of species as a function of altitude (in a comparison of top and foot of the hill) and in periods of the wet and dry, with an increase in the season wet. The increase the diversity in this period and altitude elevations can be explained by the increases in humidity after rainfalls and maintenance of temperature enabled by the conditions in the hill’s top. Our findings provide valuable information regarding termite diversity in semiarid areas as a function of elevation and contribute to other studies that are expanding our understanding of how elevation can affect these organisms.

Resumo: A Cooperativa de Valorização de Resíduos, em Porto Real - Ilha do Príncipe, desenvolve a sua atividade através da reciclagem de vidro, que transforma em joias artesanais, sendo este trabalho desenvolvido pelas mulheres que constituem a cooperativa. A intenção deste artigo é dar a conhecer o potencial educativo da cooperativa através do envolvimento das escolas, contribuindo para o desenvolvimento da Ilha, acentuando o seu papel enquanto Reserva Mundial da Biosfera. Para o efeito, foi realizado um estudo de caso de cariz qualitativo, com vista a analisar as perceções de diferentes atores sociais envolvidos. Os dados foram recolhidos através de entrevistas semiestruturadas e tratados com recurso à análise de conteúdo. Os resultados obtidos apontam para a necessidade de aproximação da cooperativa às escolas com o objetivo de sensibilizar as crianças e jovens para a necessidade de separação e reciclagem dos materiais dispersos pela Ilha, numa perspetiva de todos contribuírem para o seu desenvolvimento e para a minimização dos impactes ambientais existentes na mesma.

Abstract: The Waste Valorisation Cooperative, in Porto Real - Príncipe Island, develops its activity through the recycling of glass, which is transformed into handmade jewellery, this work is developed by the women who make up the cooperative. The intention of this article is to show the educational potential of the cooperative through the involvement of schools, contributing to the development of the Island, emphasizing its role as a World Biosphere Reserve. For this purpose, a qualitative case study was carried out, with a view to analyse the perceptions of different social actors involved. Data was collected through semi-structured interviews and treated using content analysis. The results obtained point to the need for the cooperative to approach schools in order to sensitize children and young people to the need for separation and recycling of materials dispersed throughout the island, in a perspective of all contributing to their development and minimizing environmental impacts in the island.

A scientific theory consists of a symbolic framework containing laws and concepts that are derived by deductive reasoning from fundamental laws and primitive concepts, and complemented by the correspondence or the relation between the symbolic concepts and the real objects. The symbolic framework is understood as a representation of the real, constructed by our minds like a realistic painting. In accordance with this point of view, scientific laws are not discovered but conceived or created by our minds. We show how this approach is organized by rational thinking, which is understood as an innate ability of the mind that emerges between childhood and adolescence. We also examine with some detail the structure of the past scientific theories, pointing out their postulates, or fundamental laws, and the primitive concepts. We will restrict ourselves to some of the physical theories, starting with those that emerged in the Hellenistic period, and then proceed to examine other theories until the end of the seventeenth century.

We present an analysis of the first analytical physical theories developed after the introduction of calculus. The underlying framework of these theories is the differential and integral calculus in the form developed by Leibniz. We point out the fundamental laws, or principles, or postulates upon which they are founded, and show some results or laws that are derived from them. We point out the main concepts of the theories drawing attention to the primitive or primary concepts, which are those undefinable. The theories that we describe are those that emerged just after the introduction of calculus, from Varignon to Navier. The areas of these theories include mechanics, electricity, magnetism, light, propagation of sound and propagation of heat.

Resumo A pandemia COVID-19 implicou alterações no funcionamento do sistema de saúde, com interrupção da atividade clínica programada, que, associada ao receio pelos doentes do risco de contaminação, condicionou o atendimento médico. No presente artigo analisámos os dados da atividade nos centros de Cardiologia dos hospitais CUF Infante Santo e CUF Porto durante o estado de emergência nacional. Estes hospitais, com características semelhantes na multifuncionalidade cardiovascular e integrados nos centros para tratamento da COVID-19, tiveram uma redução superior a 70% nas consultas presenciais, ultrapassando os 60% para a quase totalidade dos exames complementares de diagnóstico, em comparação com o período homólogo de 2019. Estes valores foram mais acentuados na evolução do primeiro quadrimestre de 2020, sobretudo à custa de atividade residual em abril. Os procedimentos invasivos eletivos também diminuíram, apresentando uma queda mais marcada em abril. No entanto, as intervenções urgentes por síndroma coronária aguda mantiveram-se sem variação face a igual período de 2019. Reforça-se a necessidade de divulgar a importância de recorrer às urgências hospitalares e da manutenção das normas de segurança na retoma gradual da atividade, e aborda-se o papel crescente da telemedicina e assistência domiciliária, bem como da reorganização do funcionamento das equipas hospitalares para melhorar a dinâmica multidisciplinar nas várias componentes da Cardiologia.

Abstract The COVID-19 Pandemic involved changes in the organization of the health care system, with interruption of the clinical programmed activity during the lockdown period, which, associated with the fear of contamination, had important repercussions in medical care. In this article, we analyzed data from the cardiology centers of CUF Infante Santo and CUF Porto hospitals during the state of national emergency. These hospitals, with similar characteristics in cardiovascular multifunctionality and integrated in the centers for treatment of COVID-19, had a reduction of more than 70% of face-to-face consultations, surpassing 60% for almost all diagnostic tests, compared to the same period of 2019. This was even more pronounced when looking for the evolution during the first four months of 2020. Elective invasive procedures were also reduced, with a marked fall in April. However, urgent interventions due to acute coronary syndromes remained unchanged compared to the same period in 2019. The need to inform the population regarding the importance of using hospital emergencies and the maintenance of safety recommendations is reinforced, and the growing role of telemedicine and home-based care is addressed, as well as the reorganization of the hospital teams to improve the multidisciplinary dynamicity in Cardiology.

Resumo A pandemia COVID-19 implicou profundas e rápidas mudanças no funcionamento dos serviços de saúde. A suspensão da atividade eletiva no período de confinamento e a redução significativa das idas às urgências hospitalares, condicionada pelo receio de contágio COVID-19, levaram ao adiamento do tratamento de situações cardiovasculares potencialmente graves, apesar do normal funcionamento da via verde coronária e do acidente vascular cerebral (AVC). Estes fatores facilitaram a descompensação de diferentes patologias, contribuindo provavelmente para o aumento da mortalidade na população idosa em Portugal durante a pandemia. O artigo sublinha a importância de manter a sociedade informada sobre a necessidade de recorrer às urgências hospitalares, de forma a permitir a intervenção atempada e maior benefício no tratamento do enfarte do miocárdio e AVC.

Abstract The COVID-19 pandemic involved profound and rapid changes in the functioning of health care services. The interruption of clinical programmed activity during the lockdown period and the significant reduction in visits to emergency departments, due to the fear of COVID-19, led to the postponement of appropriate treatment for potentially serious cardiovascular conditions, despite the normal functioning of the interventional units for acute myocardial infarction and stroke. These factos contributed to the decompensation of different pathologies, probably influencing the observed increase in mortality of elderly population in Portugal during the pandemic. This article stresses the importance of keeping population informed about the importance of hospital emergencies in cardiovascular care, in order to allow for timely intervention and greater benefits in the treatment of myocardial infarction and stroke.

We present an analysis of six deterministic models for epidemic spreading. The evolution of the number of individuals of each class is given by ordinary differential equations of the first order in time, which are set up by using the laws of mass action providing the rates of the several processes that define each model. The epidemic spreading is characterized by the frequency of new cases, which is the number of individuals that are becoming infected per unit time. It is also characterized by the basic reproduction number, which we show to be related to the largest eigenvalue of the stability matrix associated with the disease-free solution of the evolution equations. We also emphasize the analogy between the outbreak of an epidemic with a critical phase transition. When the density of the population reaches a critical value the spreading sets in, a result that was advanced by Kermack and McKendrick in their study of a model in which the recovered individuals acquire permanent immunization, which is one of the models analyzed here.

Abstract The stochastic thermodynamics provides a framework for the description of systems that are out of thermodynamic equilibrium. It is based on the assumption that the elementary constituents are acted by random forces that generate a stochastic dynamics, which is here represented by a Fokker-Planck-Kramers equation. We emphasize the role of the irreversible probability current, the vanishing of which characterizes the thermodynamic equilibrium and yields a special relation between fluctuation and dissipation. The connection to thermodynamics is obtained by the definition of the energy function and the entropy as well as the rate at which entropy is generated. The extension to quantum systems is provided by a quantum evolution equation which is a canonical quantization of the Fokker-Planck-Kramers equation. An example of an irreversible systems is presented which shows a nonequilibrium stationary state with an unceasing production of entropy. A relationship between the fluxes and the path integral is also presented.