56 research outputs found

    Análisis didáctico del proceso matemático de modelización en alumnos de secundaria

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    En este trabajo se analiza didácticamente el proceso matemático de modelización en relación con las dificultades y errores de un grupo de alumnos de educación secundaria. Se consideran dos situaciones problemáticas relativas a este proceso, que se estudian desde las perspectivas epistemológica, semiótica y fenomenológica que propone el Enfoque Lógico Semiótico (ELOS) (Socas, 2007). Se concluye relacionando estas dificultades y errores de los alumnos con la organización de la enseñanza de la modelización en la secundaria, mostrando también el papel que juegan en dicho proceso otros como la sustitución formal y la generalización, así como las estructuras y las operaciones matemáticas implicadas en el mismo

    Análisis y clasificación de errores cometidos por alumnos de secundaria en los procesos de sustitución formal, generalización y modelización en álgebra

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    EN esta ponencia se presenta un estudio con alumnos de Educación Secundaria sobre tres procesos específicos del lenguaje algebraico: la sustitución formal, la generalización y la modelización. A partir de las respuestas dadas a un cuestionario diseñado para esta investigación, se realiza una clasificación de los errores cometidos y se analizan los posibles orígenes de dichos errores

    Análisis y clasificación de errores cometidos por alumnos de secundaria en los procesos de sustitución formal, generalización y modelización en álgebra

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    Presentamos un estudio con alumnos de educación secundaria sobre tres procesos específicos del lenguaje algebraico: la sustitución formal, la generalización y la modelización. A partir de las respuestas a un cuestionario, realizamos una clasificación de los errores cometidos y se analizan sus posibles orígenes. Finalmente, formulamos algunas consecuencias didácticas que se derivan de estos resultados

    Secondary students´ error analysis and classification in formal substitution, generalization and modelling process in algebra

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    Presentamos un estudio con alumnos de educación secundaria sobre tres procesos específicos del lenguaje algebraico: la sustitución formal, la generalización y la modelización. A partir de las respuestas a un cuestionario, realizamos una clasificación de los errores cometidos y se analizan sus posibles orígenes. Finalmente, formulamos algunas consecuencias didácticas que se derivan de estos resultados.We present a study with secondary students about three specific processes of algebraic language: Formal substitution, generalization, and modelling. Using a test, we develop a students´ errors classifications, and we analyze its possible origins. Finally we present some didactical conclusions from the results

    El yacimiento arqueológico de El Saucedo (Talavera La Nueva, Toledo): balance y perspectivas

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    En este artículo presentamos una síntesis de los trabajos de investigación, conservación y difusión reali-zados en el yacimiento de b'l Saucedo hasta el presente, así como un esbozo de los planes de actuación para el futuro

    Antitubercular drugs for an old target: GSK693 as a promising InhA direct inhibitor

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    AbstractDespite being one of the first antitubercular agents identified, isoniazid (INH) is still the most prescribed drug for prophylaxis and tuberculosis (TB) treatment and, together with rifampicin, the pillars of current chemotherapy. A high percentage of isoniazid resistance is linked to mutations in the pro-drug activating enzyme KatG, so the discovery of direct inhibitors (DI) of the enoyl-ACP reductase (InhA) has been pursued by many groups leading to the identification of different enzyme inhibitors, active against Mycobacterium tuberculosis (Mtb), but with poor physicochemical properties to be considered as preclinical candidates. Here, we present a series of InhA DI active against multidrug (MDR) and extensively (XDR) drug-resistant clinical isolates as well as in TB murine models when orally dosed that can be a promising foundation for a future treatment

    Abnormal accumulation of autophagic vesicles correlates with axonal and synaptic pathology in young Alzheimer’s mice hippocampus

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    Dystrophic neurites associated with amyloid plaques precede neuronal death and manifest early in Alzheimer’s disease (AD). In this work we have characterized the plaque-associated neuritic pathology in the hippocampus of young (4- to 6-month-old) PS1M146L/APP751SL mice model, as the initial degenerative process underlying functional disturbance prior to neuronal loss. Neuritic plaques accounted for almost all fibrillar deposits and an axonal origin of the dystrophies was demonstrated. The early induction of autophagy pathology was evidenced by increased protein levels of the autophagosome marker LC3 that was localized in the axonal dystrophies, and by electron microscopic identification of numerous autophagic vesicles filling and causing the axonal swellings. Early neuritic cytoskeletal defects determined by the presence of phosphorylated tau (AT8-positive) and actin–cofilin rods along with decreased levels of kinesin-1 and dynein motor proteins could be responsible for this extensive vesicle accumulation within dystrophic neurites. Although microsomal Aβ oligomers were identified, the presence of A11-immunopositive Aβ plaques also suggested a direct role of plaque-associated Aβ oligomers in defective axonal transport and disease progression. Most importantly, presynaptic terminals morphologically disrupted by abnormal autophagic vesicle buildup were identified ultrastructurally and further supported by synaptosome isolation. Finally, these early abnormalities in axonal and presynaptic structures might represent the morphological substrate of hippocampal dysfunction preceding synaptic and neuronal loss and could significantly contribute to AD pathology in the preclinical stages

    Impact of the COVID-19 pandemic on the self-care and health condition of the older adults. CUIDAMOS+75. A mixed methods study protocol

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    AimsTo assess the impact of the COVID-19 pandemic on the health condition of people ≥75 years of age and on their family caregivers in Spain.DesignMulticentric, mixed method concurrent study.MethodsThis work, which will be conducted within the primary care setting in 11 administrative regions of Spain, will include three coordinated studies with different methodologies. The first is a population-based cohort study that will use real-life data to analyze the rates and evolution of health needs, care provision, and services utilization before, during, and after the pandemic. The second is a prospective cohort study with 18 months of follow-up that will evaluate the impact of COVID-19 disease on mortality, frailty, functional and cognitive capacity, and quality of life of the participants. Finally, the third will be a qualitative study with a critical social approach to understand and interpret the social, political, and economic dimensions associated with the use of health services during the pandemic. We have followed the SPIRIT Checklist to address trial protocol and related documents. This research is being funded by the Instituto de Salud Carlos III since 2021 and was approved by its ethics committee (June 2022).DiscussionThe study findings will reveal the long-term impact of the COVID-19 pandemic on the older adults and their caregivers. This information will serve policymakers to adapt health policies to the needs of this population in situations of maximum stress, such as that produced by the COVID-19 pandemic.Trial RegistrationIdentifier: NCT05249868 [ClinicalTrials.gov]

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio
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