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Depolymerization reactions constitute frequent experiments, for instance in biochemistry for the study of amyloid fibrils. The quantities experimentally observed are related to the time dynamics of a quantity averaged over all polymer sizes, such as the total polymerised mass or the mean size of particles. The question analysed here is to link this measurement to the initial size distribution. To do so, we first derive, from the initial reaction system $$\mathcal{C}_i \stackrel{b}{\longrightarrow} \mathcal{C}_{i-1} + \mathcal{C}_1,\qquad i\geq i_0\geq 2,$$ two asymptotic models: at first order, a backward transport equation, and at second order, an advection-diffusion/Fokker-Planck equation complemented with a mixed boundary condition at $x = 0$. We estimate their distance to the original system solution. We then turn to the inverse problem, i.e., how to estimate the initial size distribution from the time measurement of an average quantity, given by a moment of the solution. This question has been already studied for the first order asymptotic model, and we analyse here the second order asymptotic. Thanks to Carleman inequalities and to log-convexity estimates, we prove observability results and error estimates for a Tikhonov regularization. We then develop a Kalman-based observer approach, and implement it on simulated observations. Despite its severely ill-posed character, the second-order approach appears numerically more accurate than the first-order one.

Under low concentrations of antibiotics causing DNA damage, \textit{Escherichia coli} bacteria can trigger stochastically a stress response known as the SOS response. While the expression of this stress response can make individual cells transiently able to overcome antibiotic treatment, it can also delay cell division, thus impacting the whole population's ability to grow and survive. In order to study the trade-offs that emerge from this phenomenon, we propose a bi-type age-structured population model that captures the phenotypic plasticity observed in the stress response. Individuals can belong to two types: either a fast-dividing but prone to death ``vulnerable'' type, or a slow-dividing but ``tolerant'' type. We study the survival probability of the population issued from a single cell as well as the population growth rate in constant and periodic environments. We show that the sensitivity of these two different notions of fitness with respect to the parameters describing the phenotypic plasticity differs between the stochastic approach (survival probability) and the deterministic approach (population growth rate). Moreover, under a more realistic configuration of periodic stress, our results indicate that optimal population growth can only be achieved through fine-tuning simultaneously both the induction of the stress response and the repair efficiency of the damage caused by the antibiotic.

Após a fase inicial do atendimento aos traumatizados graves, o trauma cranioencefálico (TCE) é a principal causa de morte e sequelas permanentes. O sangramento maciço, por sua vez, representa 50% das mortes por trauma nas primeiras 24 horas. A estratégia de reanimação hemostática por meio do protocolo de transfusão maciça (PTM) aumenta a sobrevida dos doentes com sangramento maciço, mas pouco foi estudado em relação ao impacto no desfecho dos doentes com TCE grave que receberam transfusão liberal. O objetivo deste estudo foi avaliar o desfecho neurológico e a mortalidade dos indivíduos com TCE grave que foram incluídos no PTM, quando comparados aos que não foram. Fizeram parte do estudo amostra populacional de indivíduos tratados na Unidade de Emergência do Hospital das Clínicas da FMRP-USP (UEHCFMRP-USP) entre 1º de agosto de 2013 e 31 de julho de 2018, em decorrência de eventos traumáticos contusos, com idade igual ou superior a 15 anos. As vítimas de trauma contuso foram identificadas no banco de dados da Divisão de Cirurgia de Urgência e Trauma. Dentre os traumatismos contusos (TC) foram identificados os doentes com TCE grave definidos pela Escala de Coma de Glasgow, bem como aqueles que receberam o PTM. Com base no levantamento foram analisadas as variáveis do estudo em doentes com TC e TCE que não receberam o PTM e doentes com TC e TCE que receberam o PTM, avaliando desfecho neurológico no momento da alta hospitalar por meio da escala de Rankin modificada (ERM), além da mortalidade. Neste estudo foi encontrado amplo predomínio do sexo masculino, envolvendo eventos com motocicletas, onde as lesões de crânio estiveram associadas ao pior desfecho neurológico e ao óbito. O desfecho neurológico com sequelas graves e óbito foi 80% maior nos indivíduos que não receberam sangue e seus componentes por meio do PTM em comparação com o grupo que recebeu o PTM. A transfusão na fase inicial, por meio do PTM, de sangue e seus componentes parece proteger os doentes com TCE grave, entretanto novos estudos são necessários considerando maior casuística.

Atualmente, diante da situação de intensa degradação do ambiente natural, a preocupação, especialmente no que tange a preservação dos recursos naturais, está presente na vida de grande parte da população mundial. Matas ciliares são sistemas constantemente degradados apesar de sua relevante e reconhecida importância, por formarem corredores ecológicos e servir de barreiras de proteção das nascentes e corpos d’água. Vários são os fatores de degradação desses ambientes, mas é através de ações de conservação e recuperação, por meio da educação ambiental, que se pode proporcionar a retomada das características ambientais próximas do natural. O presente trabalho teve como objetivo mostrar a importância do processo de preservação das matas ciliares. O trabalho foi realizado por meio de revisão bibliográfica a partir de dados qualitativos. Conclui-se que a partir das considerações e exemplos relatados ao longo deste trabalho, emerge a importância das áreas de Conservação Permanente para permitir uma produção sustentável a longo prazo no terreno aliando qualidade ambiental e bem-estar da população. Assim, deixamos como ponto geral que todos os benefícios advindos da adopção de boas práticas associadas à manutenção de preservação transcendem as fronteiras de uma unidade produtiva rural, adquirindo, como um todo, grande importância social com impactos no urbano, ambiente e afetando toda a sociedade.

Ocular emergencies are a frequent occurrence in the emergency setting. Fortunately, point-of-care ultrasound (POCUS) lends itself exceptionally well to ocular evaluation. Here, we present a unique case of central retinal artery occlusion rapidly diagnosed with POCUS in a patient with a recent COVID-19 diagnosis.

Maintaining dialysis vascular access is a source of considerable morbidity in patients with end-stage renal disease (ESRD). High-resolution radiofrequency (RF) ultrasound vascular strain imaging has been applied experimentally in the vascular access setting to assist in diagnosis and management. Unfortunately, high-resolution RF data are not routinely accessible to clinicians. In contrast, the standard DICOM formatted B-mode ultrasound data are widely accessible. However, B-mode, representing the envelope of the RF signal, is of much lower resolution. If strain imaging could use open-source B-mode data, these imaging techniques could be more broadly investigated. We conducted experiments to detect wall strain signals with submillimeter tracking resolutions ranging from 0.2 mm (3 pixels) to 0.65 mm (10 pixels) using DICOM B-mode data. We compared this submillimeter tracking to the overall vascular distensibility as the reference measurements to see if high-strain resolution strain could be detected using open-source B-Mode data. We measured the best-fit coefficient of determination between signals, expressed as the percentage of strain waveforms that exhibited a correlation with a p value of 0.05 or less. The lowest percentage was 86.7%, and most were 90% and higher. This indicates high-resolution strain signals can be detected within the vessel wall using B-mode DICOM data.

Teacher training in Brazil is analyzed through the application of an assessment instrument called ENADE.The evaluations are expected to be aligned with the theories and studies in the study area and in line with the guidelines that guide the courses.In this context, the guiding question of this study emerges: How does ENADE for graduates in mathematics present issues related to CTS education?To answer these questions, this study was based on the assessments of ENADE in 2014 and 2017.This work is in line with qualitative research and uses document analysis as a procedure.It was observed that, even considering some advances, there is a significant gap in what is expected of the future teacher based on what CTS education and critical mathematics education recommend.

The Center for Disease Control and Prevention (CDC)'s 2018 Guideline for current practices in pediatric mild traumatic brain injury (mTBI; also referred to as concussion herein) systematically identified the best up-to-date practices based on current evidence and, specifically, identified recommended practices regarding computed tomography (CT), magnetic resonance imaging (MRI), and skull radiograph imaging. In this article, we discuss types of neuroimaging not discussed in the guideline in terms of their safety for pediatric populations, their potential application, and the research investigating the future use of certain modalities to aid in the diagnosis and treatment of mTBI in children. The role of neuroimaging in pediatric mTBI cases should be considered for the potential contribution to children's neural and social development, in addition to the immediate clinical value (as in the case of acute structural findings). Selective use of specific neuroimaging modalities in research has already been shown to detect aspects of diffuse brain injury, disrupted cerebral blood flow, and correlate physiological factors with persistent symptoms, such as fatigue, cognitive decline, headache, and mood changes, following mTBI. However, these advanced neuroimaging modalities are currently limited to the research arena, and any future clinical application of advanced imaging modalities in pediatric mTBI will require robust evidence for each modality's ability to provide measurement of the subtle conditions of brain development, disease, damage, or degeneration, while accounting for variables at both non-injury and time-post-injury epochs. Continued collaboration and communication between researchers and healthcare providers is essential to investigate, develop, and validate the potential of advanced imaging modalities in pediatric mTBI diagnostics and management.