The mind is not a black box: children’s ideas about the writing process

This is the pre-peer reviewed version of a work that was accepted for publication in Learning and Instruction. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Learning and Instruction 16,1, (2006) http://dx.doi.org/10.1016/j.learninstruc.2005.12.007We studied children’s conceptions of the writing process while the complex cognitive activity of writing is carried out through a pictorial representation of the writing process. Sixty children attending Kindergarten, first grade and fourth grade in Bariloche, Argentina, were presented individually with a sequence of four questions about the content of a child’s thought at four key moments of writing production (anticipating, writing, revising, rereading), which were depicted on picture cards. Textual analysis, the application of Simple Correspondence Factorial Analysis (SCFA) and Modal Response procedures, indicated significant developmental changes in the focus of children’s ideas about writing. More specifically, we looked at children’s conceptions of the nature of thinking while writing, given cognitive processes of increasing complexity and internalization. Main educational implications indicate the need to rethink practices for teaching writing at initial and primary school levels in order to promote teaching interventions directed at getting pupils to be explicit, revise and redescribe their conceptions about the writing process. We suggest that learners’ conceptions of writing processes outline a tacit learning curriculum of writing, which operates by guiding learning efforts and self-evaluation standardsThis research was supported by Universidad Nacional del Comahue (B-117), ANPCYT (04- 10700) and CONICET (PEI 6134) in Argentina, and by Ministerio de Ciencia y Tecnología in Spain to a project directed by J.I. Pozo (BSO2002-01557

How do children learn how to write?: the conceptions of parents and teachers of educational communities in middle and excluded sociocultural environments

Se presenta un estudio de casos de las con-cepciones de padres y maestros de comunidades educativas en entornos socioculturales medios y marginados en Bariloche, Argentina, acerca de cómo los niños aprenden a escribir. En particular, se describe y analiza cómo suponen que los niños aprenden a escribir, qué hacen cuando aprenden, cómo los niños se dan cuenta de sus aprendizajes y cómo padres y maestros se dan cuenta de los aprendizajes de los niños. El relevamiento de los datos se llevó a cabo mediante entrevistas individuales. Las respuestas verbales de los sujetos se ana-lizaron mediante el método lexicométrico o análisis de datos textuales, que diferenció tres grupos que asocian palabras características y modalidades de la variable combinada posición educativa (padre/maestro) - sector sociocultural (medio/marginado). Sobre esta base, describimos tres concepciones de aprendizaje y de enseñanza de la escritura: a) aprendizaje basado en la verificación de lo aprendido por parte del maestro y enseñanza basada en la impresión de conocimientos (característica de maestros de sectores marginados); b) aprendizaje basado en la activación y conexión de los conocimientos previos y enseñanza basada en el encauzamiento y ampliación de los conocimientos previos (maestros de sectores medios); c) aprendizaje basado en la “natural” orientación de los niños hacia el aprendizaje y enseñanza basada en provisión de modelos y respuesta a demandas de los niños (padres de ambos sectores). Se plantea que la primera concepción se vincula con una teoría directa o de la copia de la mente del aprendiz, en tanto las otras dos serían versiones de una teoría interpretativa de la mente. Se discuten las implicancias educativas de esta situaciónWe present a case study of the conceptions teachers and parents hold about the children’s learning of writing, in educational communities in middle and excluded sociocultural environments in Bariloche, Argentina. In particular, their ideas about the following issues are described: how children learn to write, what children do when they learn, how children realize they learn, how teachers and parents realize children learn. Data collection consisted in individual interviews. Verbal responses were analysed with the lexicometric method, allowing to distinguish three groups, by associating characteristic words and modalities of the combined variable educational position (teacher vs. parent) - sociocultural environment (middle vs. excluded). On this basis, we described three conceptions of learning and teaching of writ-ing: a) learning based on teacher’s verification of learning results, and teaching based on the impression of knowledge (characteristic of teachers working in excluded environments); b) learning based on the activation and connection of prior knowledge, and teaching based on channelling and enlarging prior knowledge (teachers working in middle sociocultural en-vironments) and c) learning based on children’s natural orientation to learn, and teaching based on the provision of models and on the response to children’s demands (parents from both environments). We propose that the first conception is related to a director copy theory of mind, whereas the other two are versions of an interpretative theory of mind. Educational implications are discussedEsta investigación ha sido apoyada por la Universidad Nacional del Comahue (subsidio B-093) y por el CONICET de Argentina (PEI 017

Exploring the “resistance change per energy unit” as universal performance parameter for resistive switching devices

© Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Resistive switching (RS) device (memristor) technology is continuously maturing towards industrial establishment. There are RS devices that demonstrate an “incremental” (analog) switching behavior, whereas others change their state in a binary form. The final achieved resistance is generally a function of the applied pulse characteristics, i.e. amplitude and duration. However, variability —both from device to device but also from cycle to cycle— and the stochastic nature of internal RS phenomena, still hold back any universal tuning approach based solely on these two magnitudes, making also difficult the qualitative comparison between devices with different material compounds owing to the required SET/RESET voltages being dependent on the biasing conditions. In this work we demonstrate experimentally using commercial RS devices from Knowm Inc. that the switching energy is very insensitive to the biasing conditions. We explored experimentally the SET-RESET behavior of bipolar RS devices from the energy point of view. We figured out the quantitative effect of the injected energy to the resistive state of the devices, and proposed an analytical model to explain our observations in the energy consumed by the device during the switching process. Our results lay the foundations for the definition of “resistance change per energy unit” as a performance parameter for this emerging device technology.Peer ReviewedPostprint (author's final draft

Beneficial role of noise in Hf-based memristors

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The beneficial role of noise in the performance of Hf-based memristors has been experimentally studied. The addition of an external gaussian noise to the bias circuitry positively impacts the memristors characteristics by increasing the OFF/ON resistances ratio. The known stochastic resonance effect has been observed, when changing the standard deviation of the noise. The influence of the additive noise on the memristor current-voltage characteristic and on the set and reset related parameters are also presented.This research was funded by Spanish MCIN/AEI/10.13039/501100011033, Project PID2019- 103869RB and TEC2017-90969-EXP.Peer ReviewedPostprint (author's final draft

Experimental verification of memristor-based material implication NAND operation

Memristors are being considered as promising devices for highly dense memory systems as well as the potential basis of new computational paradigms. In this scenario, and in relation with data processing, one of the more specific and differential logic functions is the material implication logic also named as IMPLY logic. Many papers have been published in this framework but few of them are related with experimental works using real memristor devices. In the paper authors show the verification of the IMPLY function by using $\mathrm{Ni}/\mathrm{HfO}_{2}/\mathrm{Si}$ manufactured devices and laboratory measurements. The proper behavior of the IMPLY structure (2 memristors) has been shown. The paper also verifies the proper operation of a two-steps IMPLY-based NAND gate implementation, showing the electrical behavior of the circuit in a cycling operation. A new procedure to implement a NAND gate that requires only one step is experimentally shown as well.Postprint (author's final draft

Stochastic resonance effect in binary STDP performed by RRAM devices

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The beneficial role of noise in the binary spike time dependent plasticity (STDP) learning rule, when implemented with memristors, is experimentally analyzed. The two memristor conductance states, which emulate the neuron synapse in neuromorphic architectures, can be better distinguished if a gaussian noise is added to the bias. The addition of noise allows to reach memristor conductances which are proportional to the overlap between pre- and post-synaptic pulses.This research was funded by the Spanish MCIN/AEI/10.13039/501100011033, Projects PID2019- 103869RB and TEC2017-90969-EXP. The Spanish MicroNanoFab ICTS is acknowledged for sample fabrication.Peer ReviewedPostprint (author's final draft

Usual dietary treatment of gestational diabetes mellitus assessed after control diet in randomized controlled trials : subanalysis of a systematic review and meta-analysis

Peer reviewe

Recensiones [Revista de Historia Económica Año XVI Primavera-Verano 1998 n. 2 pp. 573-606]

Editada en la Fundación Empresa PúblicaJuan E. Gelabert. La bolsa del Rey. Rey, reino y fisco en Castilla (1598-1648) (Por Francisco Comín).-- Ángel García Sanz y Jesús Sanz Fernández (eds.). Reformas y políticas agrarias en la historia de España (de la Ilustración al primer franquismo) (Por Rafael Serrano García).-- Jean-Yves Grenier. L'économie d'Ancien Regime. Un monde de l'éxchange et de l'incertitude (Por María Teresa Pérez Picazo).-- J. Bottin y N. Pellegrin (eds.). Échanges et cultures textiles dans l'Europe préindustrielle (Por Hilario Casado Alonso).-- Martin Baumeister. Campesinos sin tierra. Supervivencia y resistencia en Extremadura (1880-1923) (Por Juan García Pérez).-- Arantzazu Galarza. Los orígenes del empresario vasco. Creación de sociedades e inversión de capital, Bilbao (1850-1882) (Por Carlos Larrinaga Rodríguez).-- Ignacio Goenage. Estado actual y porvenir de la industria minero-metalúrgica de Vizcaya, Guipúzcoa, Navarra y Santander (Por Hilario Rodríguez de Gracia).-- Santiago de Luxán Meléndez y José Luis Quesada González. Atlantis Publicidad, 1945-1995. Historia de una empresa familiar (Por Montserrat Gárate Ojanguren).-- Sandra Kuntz Ficker y Paolo Riguzzi (coords.). Ferrocarriles y vida económica en México (1850-1950) (Por Juan Carlos Sola Corbacho).-- Rory Miller. Britain and Latin America in the Nineteenth and Twentieth centuries (Por Raúl García Hera)Publicad

Neuromyelitis optica spectrum disorders. Comparison according to the phenotype and serostatus

Objective: To (1) determine the value of the recently proposed criteria of neuromyelitis optica (NMO) spectrum disorder (NMOSD) that unify patients with NMO and those with limited forms (NMO/LF) with aquaporin-4 immunoglobulin G (AQP4-IgG) antibodies; and (2) investigate the clinical significance of the serologic status in patients with NMO. Methods: This was a retrospective, multicenter study of 181 patients fulfilling the 2006 NMO criteria (n = 127) or NMO/LF criteria with AQP4-IgG (n = 54). AQP4-IgG and myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG) antibodies were tested using cell-based assays. Results: Patients were mainly white (86%) and female (ratio 6.5:1) with median age at onset 39 years (range 10-77). Compared to patients with NMO and AQP4-IgG (n = 94), those with NMO/LF presentedmore often with longitudinally extensive transverse myelitis (LETM) (p<0.001), and had lower relapse rates (p = 0.015), but similar disability outcomes. Nonwhite ethnicity and optic neuritis presentation doubled the risk for developing NMO compared with white race (p = 0.008) or LETM presentation (p = 0.008). Nonwhite race (hazard ratio [HR] 4.3, 95% confidence interval [CI] 1.4-13.6) and older age at onset were associated with worse outcome (for every 10-year increase, HR 1.7, 95% CI 1.3-2.2). Patients with NMO and MOG-IgG (n = 9) had lower female: male ratio (0.8:1) and better disability outcome than AQP4-IgG-seropositive or double-seronegative patients (p<0.001). Conclusions: In patients with AQP4-IgG, the similar outcomes regardless of the clinical phenotype support the unified term NMOSD; nonwhite ethnicity and older age at onset are associated with worse outcome. Double-seronegative and AQP4-IgG-seropositive NMO have a similar clinical outcome. The better prognosis of patients with MOG-IgG and NMO suggests that phenotypic and serologic classification is useful

Design, synthesis and biological evaluation of N-methyl-N-[(1,2,3-triazol-4-yl)alkyl]propargylamines as novel monoamine oxidase B inhibitors

Different azides and alkynes have been coupled via Cu-catalyzed 1,3-dipolar Huisgen cycloaddition to afford a novel family of N1- and C5-substituted 1,2,3-triazole derivatives that feature the propargylamine group typical of irreversible MAO-B inhibitors at the C4-side chain of the triazole ring. All the synthesized compounds were evaluated against human MAO-A and MAO-B. Structure-activity relationships and molecular modeling were utilized to gain insight into the structural and chemical features that enhance the binding affinity and selectivity between the two enzyme isoforms. Several lead compounds, in terms of potency (submicromolar to low micromolar range), MAO-B selective recognition, and brain permeability, were identified. One of these leads (MAO-B IC50 of 3.54 μM, selectivity MAO-A/MAO-B index of 27.7) was further subjected to reversibility and time-dependence inhibition studies, which disclosed a slow and irreversible inhibition of human MAO-B. Overall, the results support the suitability of the 4-triazolylalkyl propargylamine scaffold for exploring the design of multipotent anti-Alzheimer compounds endowed with irreversible MAO-B inhibitory activity