The dialectic relationship between theory and practicein mathematics teacher education

The study presented here is a part of ongoing research, in which 'situated knowledge'and ‘cognitive apprenticeship’ form the framework that allows us to deal with theknowledge and the learning process of pre-service elementary school teachers. Ouraim is to determine how student teachers use conceptual tools provided in amathematics methods course. The search context of this paper is the curricularanalysis of the textbooks. Our research has shown the difficulty involved in usingdifferent conceptual tools to solve a proposed task. We have observed how, insituations in which the integration of conceptual tools has been achieved, the studentteachers have found distinct features that lead to different decisions. This shows theprofessional relevance of such integration and points out the need of advancing inthat research agenda

Una aproximación a las matemáticas en el bachillerato. ¿qué se pretende que aprendan los alumnos?

En este artículo nos hemos planteado indagar sobre la forma en la que se presentan los metaconceptos definir, probar y modelar en los textos escolares, consideramos estos últimos como u n texto en el que “mirar” unos significados que, de alguna manera, van a intervenir en lo que aprenden los estudiantes. Nos centramos, en primer lugar, en la elaboración de un marco común que fije unas variables que permitan caracterizar dichos metaconceptos. En segundo lugar, presentaremos algunos resultados, como son la potenciación de la adquisición de un vocabulario básico, la relativa importancia de probar, la poca importancia del metaconcepto modelar, que se vincula a la resolución de problemas concretos y aplicados

Effectiveness of Fosfomycin for the Treatment of Multidrug-Resistant Escherichia coli Bacteremic Urinary Tract Infections

IMPORTANCE The consumption of broad-spectrum drugs has increased as a consequence of the spread of multidrug-resistant (MDR) Escherichia coli. Finding alternatives for these infections is critical, for which some neglected drugs may be an option. OBJECTIVE To determine whether fosfomycin is noninferior to ceftriaxone or meropenem in the targeted treatment of bacteremic urinary tract infections (bUTIs) due to MDR E coli. DESIGN, SETTING, AND PARTICIPANTS This multicenter, randomized, pragmatic, open clinical trial was conducted at 22 Spanish hospitals from June 2014 to December 2018. Eligible participants were adult patients with bacteremic urinary tract infections due to MDR E coli; 161 of 1578 screened patients were randomized and followed up for 60 days. Data were analyzed in May 2021. INTERVENTIONS Patients were randomized 1 to 1 to receive intravenous fosfomycin disodium at 4 g every 6 hours (70 participants) or a comparator (ceftriaxone or meropenem if resistant; 73 participants) with the option to switch to oral fosfomycin trometamol for the fosfomycin group or an active oral drug or pa renteral ertapenem for the comparator group after 4 days. MAIN OUTCOMES AND MEASURES The primary outcome was clinical and microbiological cure (CMC) 5 to 7 days after finalization of treatment; a noninferiority margin of 7% was considered. RESULTS Among 143 patients in the modified intention-to-treat population (median [IQR] age, 72 [62-81] years; 73 [51.0%] women), 48 of 70 patients (68.6%) treated with fosfomycin and 57 of 73 patients (78.1%) treated with comparators reached CMC (risk difference, -9.4 percentage points; 1-sided 95% CI, -21.5 to infinity percentage points; P = .10). While clinical or microbiological failure occurred among 10 patients (14.3%) treated with fosfomycin and 14 patients (19.7%) treated with comparators (risk difference, -5.4 percentage points; 1-sided 95% CI. -infinity to 4.9; percentage points; P = .19), an increased rate of adverse event-related discontinuations occurred with fosfomycin vs comparators (6 discontinuations [8.5%] vs 0 discontinuations; P = .006). In an exploratory analysis among a subset of 38 patients who underwent rectal colonization studies, patients treated with fosfomycin acquired a new ceftriaxone-resistant or meropenem-resistant gram-negative bacteria at a decreased rate compared with patients treated with comparators (0 of 21 patients vs 4 of 17 patients [23.5%]; 1-sided P = .01). CONCLUSIONS AND RELEVANCE This study found that fosfomycin did not demonstrate noninferiority to comparators as targeted treatment of bUTI from MDR E coli; this was due to an increased rate of adverse event-related discontinuations. This finding suggests that fosfomycin may be considered for selected patients with these infections

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

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

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Higher COVID-19 pneumonia risk associated with anti-IFN-α than with anti-IFN-ω auto-Abs in children

We found that 19 (10.4%) of 183 unvaccinated children hospitalized for COVID-19 pneumonia had autoantibodies (auto-Abs) neutralizing type I IFNs (IFN-alpha 2 in 10 patients: IFN-alpha 2 only in three, IFN-alpha 2 plus IFN-omega in five, and IFN-alpha 2, IFN-omega plus IFN-beta in two; IFN-omega only in nine patients). Seven children (3.8%) had Abs neutralizing at least 10 ng/ml of one IFN, whereas the other 12 (6.6%) had Abs neutralizing only 100 pg/ml. The auto-Abs neutralized both unglycosylated and glycosylated IFNs. We also detected auto-Abs neutralizing 100 pg/ml IFN-alpha 2 in 4 of 2,267 uninfected children (0.2%) and auto-Abs neutralizing IFN-omega in 45 children (2%). The odds ratios (ORs) for life-threatening COVID-19 pneumonia were, therefore, higher for auto-Abs neutralizing IFN-alpha 2 only (OR [95% CI] = 67.6 [5.7-9,196.6]) than for auto-Abs neutralizing IFN-. only (OR [95% CI] = 2.6 [1.2-5.3]). ORs were also higher for auto-Abs neutralizing high concentrations (OR [95% CI] = 12.9 [4.6-35.9]) than for those neutralizing low concentrations (OR [95% CI] = 5.5 [3.1-9.6]) of IFN-omega and/or IFN-alpha 2

Nuevos espacios de enseñanza/aprendizaje en la formación inicial de profesores de primaria

En este trabajo nos centramos en identificar las particularidades del discurso del formador de profesores en un soporte tecnológico, tratando de obtener información que posibilite a estos profesores ser conscientes de lo que implica pasar de un medio presencial a otro virtual. En este paso, se mantienen los planteamientos teóricos que guían las trayectorias de enseñanza/aprendizaje diseñadas para contextos presenciales pero se produce una adaptación al nuevo medio. Nuestros resultados muestran algunos aspectos nuevos que pensamos deben incorporarse a los que caracterizan la comunidad de práctica a la que los formadores de profesores pertenecen.In this study we focus on identifying the particularities of teachers' educator discourse in a technological media. We try to obtain useful information to make possible to these teachers to be aware of the particularities of passing from a traditional context to a virtual context. In this step, we keep the theoretical approaches that are background of the teaching/learning trajectories designed for traditional context but and adjustment has to be produced in the process of adaptation to the new context. Our results show some new aspects that we think they must be incorporated into those who characterize the community of practice to which mathematics teachers' educators belong

Pixel-Bit

Resumen basado en el de la publicaciónSe presentan las particularidades del discurso del formador de profesores en un soporte tecnológico, tratando de obtener información que posibilite a estos profesores ser conscientes de lo que implica pasar de un medio presencial a otro virtual. En este paso, se mantienen los planteamientos teóricos que guían las trayectorias de enseñanza-aprendizaje diseñadas para contextos presenciales, pero se produce una adaptación al nuevo medio. Los resultados muestran algunos aspectos nuevos que deben incorporarse a los que caracterizan la práctica a la que los formadores de profesores pertenecen.AndalucíaBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín, 5 - 3 planta; 28014 Madrid; Tel. +34917748000; [email protected]

Probability of germination after heat treatment of native Spanish pines

Spanish pine forests exhibit a high degree of resilience to frequent wildfires. For this reason, they have been considered as active pyrophytes. However, the primary evidence of the fire response of some of the seven Spanish pines suggests that they are not real pyrophytes because germination enhancement has not been detected. In order to investigate the germination response of the Spanish pine seeds after heating, seeds were submitted to different treatments at varying temperatures (50-130 °C) and exposure times (1-15 min) to simulate responses to different fire regimes and situations. The probability of germination after heating was modelled by means of multiple logistic regressions using temperature, time and their interaction as predictors. Very predictive models were found for all the pines, except for Pinus pinea. Seeds germinate readily without treatment, losing their viability within a short time and showing a slight protection from fire. The results suggest that, despite the fact that these pines all occur in fire-prone environments, their germination behaviour has clearly not evolved in relation to fire alone. Furthermore, seed behaviour is not related to the general syndromes described as typical of fire-evolved plants. Whereas most of the Mediterranean seeders base their efficient recruitment after wildfires on the presence of hard-coated seeds, most of the Mediterranean pines have attempted other strategies with some variants related to prolific seed production. Only P. pinea regeneration after wildfires depends on the existence of fire-resistant and hard-coated seeds. (© Inra/Elsevier, Paris.)Probabilité de germination des graines de pins d'origine espagnole après traitement par chauffage. Les pins espagnols montrent un haut degré de résilience aux feux fréquents. Pour cette raison, ils ont été considérés comme des pyrophytes actifs. Cependant, l'évidence première de la réponse au feu de certaines des sept espèces de pins espagnols suggère qu'elles ne sont pas de réelles pyrophytes car aucune augmentation de germination n'a été observée. Afin de connaître la réponse à la germination des graines après chauffage, des graines furent exposées à différents traitements de gradients de température (50 °C à 130 °C) et de durée (1 min à 15 min) afin de simuler la réponse à différents régimes de situation de feu. La probabilité de germination après chauffage a été modélisée au moyen de régressions multiples logistiques utilisant la température, la durée d'exposition et leur interaction comme variables prédictives. De très bons modèles prédictifs ont été établis pour tous les pins, excepté pour Pinus pinea. Les graines germent déjà sans traitement, perdent rapidement leur capacité germinative et montrent une faible protection au feu. Les résultats suggèrent que, en dépit du fait que tous ces pins soient localisés dans un environnement propice à l'incendie, il est clair que leur comportement germinatif n'a pas uniquement évolué en relation avec les feux. En outre, le comportement des graines n'est pas relié au syndrome général décrit comme typique de l'évolution des plantes sous l'influence du feu. Alors que la plupart des semenciers méditerranéens basent leur efficiente régénération après passage du feu sur l'existence de graines à téguments épais, la plupart des pins méditerranéens ont établi d'autres stratégies avec des variantes reliées à une production prolifique de graines. Après incendie, seule la régénération de P. pinea dépend de l'existence de graines résistantes au feu et avec des téguments épais. (© Inra/Elsevier, Paris.