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Este artigo representa o primeiro passo de uma caminhada na direção de proposta original de um currí- culo de ensino superior em Geociências. Partindo do fato que as polêmicas são basilares a qualquer ciência, sendo o debate fundamental ao questionamento dos princípios e ao processo de formação conceitual, e que as periodizações históricas das Geociências constituem instrumentos de alcance limitado à sua compreensão, este artigo visa demonstrar como a fluidez está a atuar sobre as ciências, ajudando a derrubar metanarrativas e desvelar essencialismos. Este trabalho propõe que todo cientista deva: (a) assumir função social diversa da atual, ao trazer, para o centro do debate, vozes dos que estão à margem do saber; (b) democratizar os resultados de suas experiências junto à sociedade, possibilitando ao cidadão comum agenciar suas próprias demandas, tomando por base este conhecimento.

A atual carência de docentes para atender às escolas de educação básica pode ser suprida pela formação docente apoiada em currículos impregnados de conhecimentos, modelos e práticas típicos das Geociências. Ao mesmo tempo em que dificuldades levaram o Estado a perder a condição de gerir muitas escolas, estudantes incapazes de receber informações e construir conceitos tornaram-se social e culturalmente defasados. O professor, elemento-chave do processo, deve capacitar-se para contextualizar conceitos e transmitir conteúdos fundamentais de modo organizado e integrado. Os alunos devem compreender as dificuldades inerentes ao aprendizado e reconhecer que o saber é antes uma construção social em lugar de produto natural e espontâneo de nossa interação com o mundo objetivo. Os argumentos aqui oferecidos salientam as Geociências como alicerces para o desenvolvimento intelectual, porque incorporam ao pensamento sistêmico uma clara noção de perspectiva histórica, que explica a formação do patrimônio natural brasileiro, composto pelo nosso subsolo e suas riquezas.

In this paper a new model of growing and dividing protocells is described, whose main features are (i) a lipid container that grows according to the composition of the molecular milieu (ii) a set of “genetic memory molecules” (GMMs) that undergo catalytic reactions in the internal aqueous phase and (iii) a set of stochastic kinetic equations for the GMMs. The mass exchange between the external environment and the internal phase is described by simulating a semipermeable membrane and a flow driven by the differences in chemical potentials, thereby avoiding to resort to sometimes misleading simplifications, e.g., that of a flow reactor. Under simple assumptions, it is shown that synchronization takes place between the rate of replication of the GMMs and that of the container, provided that the set of reactions hosts a so-called RAF (Reflexive Autocatalytic, Food-generated) set whose influence on synchronization is hereafter discussed. It is also shown that a slight modification of the basic model that takes into account a rate-limiting term, makes possible the growth of novelties, allowing in such a way suitable evolution: so the model represents an effective basis for understanding the main abstract properties of populations of protocells.

The growth of a population of protocells requires that the two key processes of replication of the protogenetic material and reproduction of the whole protocell take place at the same rate. While in many ODE-based models such synchronization spontaneously develops, this does not happen in the important case of quadratic growth terms. Here we show that spontaneous synchronization can be recovered (i) by requiring that the transmembrane diffusion of precursors takes place at a finite rate, or (ii) by introducing a finite lifetime of the molecular complexes. We then consider reaction networks that grow by the addition of newly synthesized chemicals in a binary polymer model, and analyze their behaviors in growing and dividing protocells, thereby confirming the importance of (i) and (ii) for synchronization. We describe some interesting phenomena (like long-term oscillations of duplication times) and show that the presence of food-generated autocatalytic cycles is not sufficient to guarantee synchronization: in the case of cycles with a complex structure, it is often observed that only some subcycles survive and synchronize, while others die out. This shows the importance of truly dynamic models that can uncover effects that cannot be detected by static graph theoretical analyses.

Desenvolveu-se modelo de análise da concepção geocientífica veiculada em livros didáticos de Ensino Superior, baseado no ciclo da água, sua dinâmica, fluxos e interações. O modelo forneceu bons resultados, ao ser aplicado ao livro "Challenge of the Natural Environment", de Knapp, Ross e McCrae, que descrevem diferentes categorias de riscos geológicos. No ensino de geociências é fundamental distinguir entre os objetos de investigação e de estudo. Os estudos geológicos buscam recompor o objeto de estudo da Geologia o processo histórico-geológico a partir das formas fixadas em rochas e materiais sólidos. O objeto de investigação é a parte acessível da Terra: a crosta, com sua ampla variedade de estruturas, composições, tramas e texturas de rochas. Ao se distinguir objeto de estudo e de investigação, avaliam-se objetivamente riscos ocasionados: (a) pelo desconhecimento dos fenômenos naturais ou (b) quando se desconsideram efeitos de atividades antrópicas sobre a natureza.This article analyses the textbook published 1991 "Challenge of the Natural Environment", written by Brian Knapp, Simon Ross and Duncan McCrae, adopting the water cycle as a dynamic background for the flows and interactions between the Earth spheres. The water cycle helps students to understand the difference between the subject matter and the investigation of Geology, a distinction which is fundamental for the teaching of Earth Sciences. Such approach helps to understand the way Geology has evolved as a science. The object of investigation is the crust, where a great diversity of structures, rock compositions, fabrics and textures exist. The subject matter is the historical-geological process reconstructed from naturally "fixed" forms. The step-by-step approach goes from the simplest to the most comprehensive concepts; it highlights the risks caused by: (a) an incomplete knowledge of natural processes or (b) absence of concern for effects of human activities on nature.

Outpatient parenteral antibiotic therapy (OPAT) has become an increasingly used therapeutic modality during the last 20 years. Reasons for this rapid growth include OPAT’s many patient benefits as well as the development of new technologies and well-documented cost savings. Recently the Italian Drug Agency (AIFA) has revised the list of drug’s limitations and indications; particularly two notes about OPAT (n. 55- n.56) have been modified. These new notes can assume at least a double significance: if on the one hand they try to put a check on the overuse and misuse of OPAT, steering physicians towards a better utilization of parenteral antibiotics, on the other they allow to prescribe OPAT also in case of non-ordinary infections, promoting development of more structured OPAT programmes. Prescribing physicians should be aware of a number of aspects of OPAT which distinguish it from other forms of therapy: multiple factors must be taken into account, including the probable infecting organism, the pharmacodynamic and pharmacokinetic properties of candidate drugs, the capabilities of patients who will receive OPAT and of their caregivers. The Infectious Diseases Society of America (IDSA) Guidelines have been elaborated to help physicians thorough assessment of OPAT suitability, even if they need to be adapted to many variables in each treatment setting. Aim of the present study is to re-consider the main microbiologic, clinical and pharmacoeconomic criteria supporting the prescription of an outpatient parenteral antibiotic therapy after the publication of the new AIFA notes.