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Currently, in science teaching and in particular, natural science teaching there are concepts in the school that have a high level of abstraction. Concepts, such as atom, gene, mole and energy, among others are difficult to explain in an understanding manner to students. This situation requires the teacher to design alternative strategies to promote meaningful learning. Give priority to teaching concepts in science promotes the conception of science as a finished, infallible construct outside the context and does not evolve; turning science learning into something monotonous and uninteresting for students. According to some researches in the line of history and epistemology of sciences, its importance and advantages are recognized to promote not only a conceptual and formal education, but also to broaden the spectrum of possibilities that allow the students to transform conceptions of science into a more dynamic and participatory paradigm. Recognizing the benefits of the use of history in science teaching, a proposal is made for the DNA structure teaching in secondary school students within the framework of the Master in Teaching of Sciences of the Fundación Universidad Autónoma de Colombia, under this perspective.

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Prion diseases are fatal neurodegenerative diseases in mammals with the unique characteristics of misfolding and aggregation of the cellular prion protein (PrPC) to the scrapie prion (PrPSc). Although neuroinflammation and neuronal loss feature within the disease process, the details of PrPC/PrPSc molecular transition to generate different aggregated species, and the correlation between each species and sequence of cellular events in disease pathogenesis are not fully understood. In this study, using mice inoculated with the RML isolate of mouse-adapted scrapie as a model, we applied asymmetric flow field-flow fractionation to monitor PrPC and PrPSc particle sizes and we also measured seeding activity and resistance to proteases. For cellular analysis in brain tissue, we measured inflammatory markers and synaptic damage, and used the isotropic fractionator to measure neuronal loss; these techniques were applied at different timepoints in a cross-sectional study of disease progression. Our analyses align with previous reports defining significant decreases in PrPC levels at pre-clinical stages of the disease and demonstrate that these decreases become significant before neuronal loss. We also identified the earliest PrPSc assemblies at a timepoint equivalent to 40% elapsed time for the disease incubation period; we propose that these assemblies, mostly composed of proteinase K (PK)–sensitive species, play an important role in triggering disease pathogenesis. Lastly, we show that the PK-resistant assemblies of PrPSc that appear at timepoints close to the terminal stage have similar biophysical characteristics, and hence that preparative use of PK-digestion selects for this specific subpopulation. In sum, our data argue that qualitative, as well as quantitative, changes in PrP conformers occur at the midpoint of subclinical phase; these changes affect quaternary structure and may occur at the threshold where adaptive responses become inadequate to deal with pathogenic processes. [ABSTRACT FROM AUTHOR]

In this work we discuss the development of a web application in the domain of movie chains using a Blackboard architecture, which is a well-established style for solving the problem of control, communication and collaboration in a system; it has traditionally been accepted as adequate for heuristic problem solving though not generally used for web applications. We present and discuss how the Blackboard architecture is used as the style for a graduate course project in Software Engineering. Issues about the implementation of the architecture are described and an assessment using some software metrics is presented. [ABSTRACT FROM AUTHOR]

Amyloid aggregation of polypeptides is related to a growing number of pathologic states known as amyloid disorders. At present, it is clear that any proteins submitted to appropriate physicochemical environment can acquire fibrilar conformation. Fourier transform infrared spectroscopy (FTIR) has been a widely used technique to study temperature- induced amyloid-fibrils formation in vitro. In this way, strict changes and temperature controls are required to characterize the physicochemical basis of the amyloid-fibrils formation. In this article, the development of a highly efficient and accurate Peltier-based system to improve FTIR measurements is presented (see An Old Physics Phenomenon Applied to a Serious Biomedical Pathology. The accuracy of the thermostatic control was tested with biophysical parameters on biological samples probing its reproducibility. The design of the present device contributes to maintain the FTIR environment stable, which represents a real contribution to improve the spectral quality and thus, the reliability of the results. [ABSTRACT FROM AUTHOR]

Nowadays there is an emerging interest on health system resilience capacity during emergencies as the one created by the COVID-19 Pandemic. This article contributes to this emerging field of studies by analysing the impact of the state´s policy responses COVID-19 (as lockdowns) on the Peruvian health system, specifically on the delivery of non-covid services, sexual and reproductive health services, and describe the strategies deployed by health workers to adapt to the COVID-19 crisis in Peru, a country that have been dramatically impacted by the pandemic. The article, based on the analysis of depth interviews with 11 health workers and one health supervisor working at sexual and reproductive health services at public health services Lima during 2020 and 2021, describe how pre-existing conditions of the health system (as poor infrastructure and deficit of human resources) magnified the negative effects of the measures taken to control de pandemic, undermining the "resilience" of the health system., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Gianella et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objectives: To present and analyze the Peruvian health system's response to the sexual and reproductive health needs of Venezuelan women living in the city of Lima, Peru, and to identify some of the reasons underlying this response., Methods: Information was collected through semi-structured, in-depth telephone interviews with 30 Venezuelan women, 10 healthcare workers, and two Ministry of Health officials., Results: Based on the experiences of Venezuelan women who sought care through these services during 2019-2020 and the perspectives of healthcare personnel and health authorities, we present an analysis of the public health services' capacity and limitations in meeting the sexual and reproductive health needs of this population. Migrant women's testimonies reported a positive experience with a health system that, despite shortcomings, responds to the most common sexual and reproductive health needs. These perspectives parallel the testimonies of healthcare personnel and authorities who emphasized the existence of priority policies for sexual and reproductive health care., Conclusion: This study shows how a national priority framework (reducing maternal mortality), accompanied by operational mechanisms for social protection (such as the Comprehensive Health Insurance program), represent complementary instruments that have a positive impact on and extend benefits to migrants, even though this population was not considered when designing these policies.