Formación docente y diálogo de saberes en el kairos educativo

A certain absence of recursive and dialogical processes in teacher training, in a context characterized by great glocal, social, political, cultural and epistemological questionings, demands the need for a discussion about the construction of other ways of improvement. Undoubtedly, teacher training in the new millennium is woven within a fabric of discussions about the different theories that constitute its framework: pedagogy, didactics, philosophy, anthropology, sociology and cultural studies, just to mention a few of those threads. It stands to reason that such weft exists as long as we are discussing a profession developed as connected and dependent to a political system which determines the fundamentals and directives to be made.In addition, within the educational institution, at any level, there is tension among the founding mandate, tradition, regulations and history, which are not able to find their place in the challenge of educating the citizen for a democratic, pluralist, inclusive and complex society. That is to say, teacher training takes place within an institution that still keeps in its core the principles and ideals of previous centuries, with comenian classrooms, highly vertical management, and lack of communication.As a contribution to the search of new ways to think training, this time, we try to analyze how the disciplinary field of dialogic or complexa didactics prepares future teachers to think their praxis with autonomy, responsibility and critical and thorough examination.A new model requires a new logic of recursive and metacognitive construction, formed by a complex epistemology which provides the tools for thinking about teacher training, its practice, the pedagogical subjects involved and the gnoseological recursiveness that determines them.Cierta ausencia de procesos recursivos y dialógicos en la formación docente –en el contexto actual caracterizado por grandes cuestionamientos glocales, sociales, políticos, culturales y epistemológicos– genera la necesidad de undebate sobre la construcción de “otras” vías de mejoramiento. Es indudable que esta formación docente –en el nuevo milenio– aparece en una trama que entreteje discusiones en las diversas teorías que conforman su andamiaje:pedagogía, didáctica, filosofía, antropología, sociología y estudios culturales, por mencionar sólo algunos de esos hilos. Y es lógico que esa urdimbre exista en tanto se habla de una profesión que se desarrolla unida y dependientede un sistema político que marca los fundamentos y directrices que deben optarse.Se suma a ello que en la institución educativa –en cualquiera de sus niveles– se tensionan mandatos fundacionales, tradiciones, normativas y trayectorias que no terminan de ubicarse en el actual desafío que significa hoy educar al ciudadano para una sociedad democrática, pluralista, inclusiva, compleja. Es decir, la formación docente se da en una institución que aún guarda en su matriz los principios e ideales de siglos anteriores, con aulas comenianas, gestión fuertemente vertical y escasa comunicación.Como aporte en la búsqueda de otra forma de pensar tal formación, en esta instancia se procura analizar cómo el campo disciplinar de la didáctica dialógica o complexa prepara a los futuros profesores para pensar su praxis con autonomía, responsabilidad y escrutinio crítico. Un nuevo modelo requiere una nueva lógica de construcción constituida por una epistemología compleja que brinde herramientas para pensar la formación docente, su práctica, los sujetos pedagógicos involucrados en la misma y la recursividad gnoseológica complejaque los determina

Water uptake by trees in a riparian hardwood forest (Rhine floodplain, France)

Water flow in the soil–root–stem system was studied in a flooded riparian hardwood forest in the upper Rhine floodplain. The study was undertaken to identify the vertical distribution of water uptake by trees in a system where the groundwater is at a depth of less than 1 m. The three dominant ligneous species (Quercus robur, Fraxinus excelsior and Populus alba) were investigated for root structure (vertical extension of root systems), leaf and soil water potential (m), isotopic signal (18O) of soil water and xylem sap. The root density of oak and poplar was maximal at a depth of 20 to 60 cm, whereas the roots of the ash explored the surface horizon between 0 and 30 cm, which suggests a complementary tree root distribution in the hardwood forest. The flow density of oak and poplar was much lower than that of the ash. However, in the three cases the depth of soil explored by the roots reached 1Ð2 m, i.e. just above a bed of gravel. The oak roots had a large lateral distribution up to a distance of 15 m from the trunk. The water potential of the soil measured at 1 m from the trunk showed a zone of strong water potential between 20 and 60 cm deep. The vertical profile of soil water content varied from 0Ð40 to 0Ð50 cm3 cm3 close to the water table, and 0Ð20 to 0Ð30 cm3 cm3 in the rooting zone. The isotopic signal of stem water was constant over the whole 24-h cycle, which suggested that the uptake of water by trees occurred at a relatively constant depth. By comparing the isotopic composition of water between soil and plant, it was concluded that the water uptake occurred at a depth of 20 to 60 cm, which was in good agreement with the root and soil water potential distributions. The riparian forest therefore did not take water directly from the water table but from the unsaturated zone through the effect of capillarit

Comprehensive inter-laboratory calibration of reference materials for δ18O versus VSMOW using various on-line high-temperature conversion techniques

Internationally distributed organic and inorganic oxygen isotopic reference materials have been calibrated by six laboratories carrying out more than 5300 measurements using a variety of high-temperature conversion techniques (HTC) in an evaluation sponsored by the International Union of Pure and Applied Chemistry (IUPAC). To aid in the calibration of these reference materials, which span more than 125‰, an artificially enriched reference water (δ18O of +78.91‰) and two barium sulfates (one depleted and one enriched in 18O) were prepared and calibrated relative to VSMOW2 and SLAP reference waters. These materials were used to calibrate the other isotopic reference materials in this study. The seemingly large estimated combined uncertainties arise from differences in instrumentation and methodology and difficulty in accounting for all measurement bias. They are composed of the 3-fold standard errors directly calculated from the measurements and provision for systematic errors discussed in this paper. A primary conclusion of this study is that nitrate samples analyzed for δ18O should be analyzed with internationally distributed isotopic nitrates, and likewise for sulfates and organics. Authors reporting relative differences of oxygen-isotope ratios (δ18O) of nitrates, sulfates, or organic material should explicitly state in their reports the δ18O values of two or more internationally distributed nitrates (USGS34, IAEA-NO-3, and USGS35), sulfates (IAEA-SO-5, IAEA-SO-6, and NBS 127), or organic material (IAEA-601 benzoic acid, IAEA-602 benzoic acid, and IAEA-600 caffeine), as appropriate to the material being analyzed, had these reference materials been analyzed with unknowns. This procedure ensures that readers will be able to normalize the δ18O values at a later time should it become necessary. The high-temperature reduction technique for analyzing δ18O and δ2H is not as widely applicable as the well-established combustion technique for carbon and nitrogen stable isotope determination. To obtain the most reliable stable isotope data, materials should be treated in an identical fashion; within the same sequence of analyses, samples should be compared with working reference materials that are as similar in nature and in isotopic composition as feasible.

An unusual case of anisocoria by vegetal intoxication: a case report

A 12 year old boy presented with an acute onset of anisocoria and blurred vision. Ocular motility was normal but his right pupil was dilated, round but sluggishly reactive to light. There was no history of trauma, eye drops' instillation, nebulised drugs or local ointments. His past medical history was negative

Attitude of Italian physicians toward pertussis diagnosis.

Resurgence of pertussis has been observed in several countries whereas Italy continues to be a low incidence country. We hypothesize that the low reported incidence of pertussis in Italy could be biased by the attitude of physicians to suspect and diagnose pertussis in different age groups. We investigated the attitude of Italian physicians toward pertussis diagnosis through clinical scenarios. A cross-sectional study was conducted in June 2012 sending online questionnaires to pediatricians and general practitioners (GPs) involved in ambulatory primary care. The questionnaire included five clinical scenarios of patients of different ages (45 d, 5 y, 11 y, 24 y, 58 y) with prolonged cough of at least 2 weeks. Respondents were asked to choose a diagnosis among a list of 14. We observed a decreasing trend of suspected pertussis diagnosis with increasing age of the patient (from 46% at 45 d to 0 at 58 y). In Italy pertussis is seldom suspected in the differential diagnosis of cough particularly in adults. This may cause a significant under-notification of pertussis, with a higher impact in older age groups. Educational programs should be reinforced to consider the differential diagnosis of pertussis in individuals with atypical presentation and in older age groups

Infants hospitalized for Bordetella pertussis infection commonly have respiratory viral coinfections

Background: Whether viral coinfections cause more severe disease than Bordetella pertussis (B. pertussis) alone remains unclear. We compared clinical disease severity and sought clinical and demographic differences between infants with B. pertussis infection alone and those with respiratory viral coinfections. We also analyzed how respiratory infections were distributed during the 2 years study. Methods: We enrolled 53 infants with pertussis younger than 180 days (median age 58 days, range 17–109 days, 64. 1% boys), hospitalized in the Pediatric Departments at “Sapienza” University Rome and Bambino Gesù Children’s Hospital from August 2012 to November 2014. We tested in naso-pharyngeal washings B. pertussis and 14 respiratory viruses with real-time reverse-transcriptase-polymerase chain reaction. Clinical data were obtained from hospital records and demographic characteristics collected using a structured questionnaire. Results: 28/53 infants had B. pertussis alone and 25 viral coinfection: 10 human rhinovirus (9 alone and 1 in coinfection with parainfluenza virus), 3 human coronavirus, 2 respiratory syncytial virus. No differences were observed in clinical disease severity between infants with B. pertussis infection alone and those with coinfections. Infants with B. pertussis alone were younger than infants with coinfections, and less often breastfeed at admission. Conclusions: In this descriptive study, no associations between clinical severity and pertussis with or without co-infections were found