The activated torsion oscillation magnetometer

The activated torsion oscillation magnetometer exploits the mechanical resonance of a cantilever beam, driven by the torque exerted on the sample by an ac field applied perpendicularly to the film plane. We describe a model for the cantilever dynamics which leads to the calculation of the cantilever dynamic profile and allows the mechanical sensitivity of the instrument to be expressed in terms of the minimum electronically detectable displacement. We have developed a capacitance detector of small oscillations which is able to detect displacements of the order of 0.1 nm. We show that sensitivities of the order of 0.5(10-11 Am2 can be in principle achieved. We will subsequently describe the main features of the ATOM prototype which we have built and tested, with particular attention to the design solutions which have been adopted in order to reduce the effects of parasitic vibrations due either to acoustic noise, originating from the ac field coil, or to eddy currents in the capacitor electrodes. The instrument is mounted in a continuous flow cryostat and can work in the 4.2-300 K temperature range. Finally, we will show that our experimental set-up has a second mode of operation, named Torsion Induction Magnetometer (TIM).Comment: Invited Talk at the Moscow International Symposium on Magnetism, 2002 to appear in the J. Mag. Mag. Mat Revised versio

Dynamical Axion Field in Topological Magnetic Insulators

Axions are very light, very weakly interacting particles postulated more than 30 years ago in the context of the Standard Model of particle physics. Their existence could explain the missing dark matter of the universe. However, despite intensive searches, they have yet to be detected. In this work, we show that magnetic fluctuations of topological insulators couple to the electromagnetic fields exactly like the axions, and propose several experiments to detect this dynamical axion field. In particular, we show that the axion coupling enables a nonlinear modulation of the electromagnetic field, leading to attenuated total reflection. We propose a novel optical modulators device based on this principle.Comment: 5 pages, 3 figure

Flexible MgO barrier magnetic tunnel junctions

Flexible electronic devices require the integration of multiple crucial components on soft substrates to achieve their functions. In particular, memory devices are the fundamental component for data storage and processing in flexible electronics. Here, we present flexible MgO barrier magnetic tunnel junction (MTJ) devices fabricated using a transfer printing process, which exhibit reliable and stable operation under substantial deformation of the device substrates. In addition, the flexible MTJ devices yield significantly enhanced tunneling magnetoresistance (TMR) of ~300 % and improved abruptness of switching, as residual strain in the MTJ structure induced by the fabrication process is released during the transfer process. This approach could be useful for a wide range of flexible electronic systems that require high performance memory components.Comment: Adv. Mat. (2016

Magnetomechanical Four-State Memory

With current non-volatile memory technology approaching intrinsic storage density limits, new data storage technologies are under development. Probe-based storage systems provide alternatives to conventional mass storage technologies. Ni-Mn-Ga, a ferromagnetic shape memory alloy (FSMA), is proposed as a medium for multi-bit storage using scanning probe microscopy (SPM) techniques. Local modifications of the magnetic stray field were achieved using nanoindentation. Magnetic poles collect within the indentation, which is leveraged to control the magnetic stray field for the patterning of magnetic information. Four magnetic-based memory states are possible due to magnetic field or stress-induced twin rearrangement along two crystal orientations, each with two possible magnetic orientations

¿Demasiado poco – demasiado tarde? Diversidad e inclusión en aulas preescolares biétnicas en Chile

Introduction: In indigenous contexts the human right of intergenerational transmission of culture and language is not always guaranteed. This study investigated to which degree pedagogical practices were implemented to promote the acceptance of diversity and the inclusion of Mapuche culture and language in 62 preschool classrooms shared by indigenous Mapuche and non-indigenous children in the south of Chile and examined whether the degree of implementation differs between public and private-subsidized educational establishments (EE). Method: A quantitative rating scale was used to measure the degree of promoting acceptance of diversity and inclusion of ethnic diversity based on extended classroom observations and preschool teacher interviews. Results: In 90,3% of the classrooms the acceptance of diversity and inclusion of Mapuche language and culture was promoted to an inadequate or minimal degree. Nevertheless, the results were significantly more favorable for public EE compared to private-subsidized EE. Conclusion: The findings provide new evidence of the urgent need to improve the intercultural education for preschool children in interethnic contexts in Chile to impede the invisibilization of indigenous culture and devaluation of indigenous knowledge.Introducción: En contextos indígenas el derecho humano de la transmisión intergeneracional de la cultura y lengua no siempre está garantizado. Este estudio investigó en qué grado se implementaron prácticas pedagógicas para promover la aceptación de la diversidad e inclusión de la cultura y lengua Mapuche en 62 aulas preescolares compartidas por niños indígenas Mapuche y niños no-indígenas en el sur de Chile, y examinó si el grado de implementación difiere entre establecimientos educacionales (EE.EE.) municipales y particulares-subvencionados. Metodología: Se utilizó una escala de calificación cuantitativa para medir el grado de promoción de la aceptación de la diversidad y de la inclusión de la diversidad étnica basado en observaciones extendidas de las aulas y entrevistas con las educadoras. Resultados: En 90.3% de las aulas se promovió la aceptación de la diversidad y la inclusión de la cultura y lengua Mapuche en un grado inadecuado o mínimo. No obstante, los resultados fueron significativamente más favorables para los EE.EE. municipales comparados con los EE.EE. particulares-subvencionados. Conclusión: Los hallazgos proveen nueva evidencia de la necesidad urgente de mejorar la educación intercultural para niños preescolares en contextos interétnicos en Chile para impedir la invisibilización de las culturas indígenas y la desvaloración de los conocimientos indígenas

Too little – too late? Diversity and inclusion in interethnic preschool classrooms in the Mapuche context in the south of Chile

Introducción: En contextos indígenas el derecho humano de la transmisión intergeneracional de la cultura y lengua no siempre está garantizado. Este estudio investigó en qué grado se implementaron prácticas pedagógicas para promover la aceptación de la diversidad e inclusión de la cultura y lengua Mapuche en 62 aulas preescolares compartidas por niños indígenas Mapuche y niños no-indígenas en el sur de Chile, y examinó si el grado de implementación difiere entre establecimientos educacionales (EE.EE.) municipales y particulares-subvencionados. Metodología: Se utilizó una escala de calificación cuantitativa para medir el grado de promoción de la aceptación de la diversidad y de la inclusión de la diversidad étnica basado en observaciones extendidas de las aulas y entrevistas con las educadoras. Resultados: En 90.3% de las aulas se promovió la aceptación de la diversidad y la inclusión de la cultura y lengua Mapuche en un grado inadecuado o mínimo. No obstante, los resultados fueron significativamente más favorables para los EE.EE. municipales comparados con los EE.EE. particulares-subvencionados. Conclusiones: Los hallazgos proveen nueva evidencia de la necesidad urgente de mejorar la educación intercultural para niños preescolares en contextos interétnicos en Chile para impedir la invisibilización de las culturas indígenas y la desvaloración de los conocimientos indígenasIntroduction: In indigenous contexts the human right of intergenerational transmission of culture and language is not always guaranteed. This study investigated to which degree pedagogical practices were implemented to promote the acceptance of diversity and the inclusion of Mapuche culture and language in 62 preschool classrooms shared by indigenous Mapuche and non-indigenous children in the south of Chile and examined whether the degree of implementation differs between public and private-subsidized educational establishments (EE). Methodology: A quantitative rating scale was used to measure the degree of promoting acceptance of diversity and inclusion of ethnic diversity based on extended classroom observations and preschool teacher interviews. Results: In 90,3% of the classrooms the acceptance of diversity and inclusion of Mapuche language and culture was promoted to an inadequate or minimal degree. Nevertheless, the results were significantly more favorable for public EE compared to private-subsidized EE. Conclusions: The findings provide new evidence of the urgent need to improve the intercultural education for preschool children in interethnic contexts in Chile to impede the invisibilization of indigenous culture and devaluation of indigenous knowledg

¿Demasiado poco – demasiado tarde? Diversidad e inclusión en aulas preescolares biétnicas en Chile

Introduction: In indigenous contexts the human right of intergenerational transmission of culture and language is not always guaranteed. This study investigated to which degree pedagogical practices were implemented to promote the acceptance of diversity and the inclusion of Mapuche culture and language in 62 preschool classrooms shared by indigenous Mapuche and non-indigenous children in the south of Chile and examined whether the degree of implementation differs between public and private-subsidized educational establishments (EE). Method: A quantitative rating scale was used to measure the degree of promoting acceptance of diversity and inclusion of ethnic diversity based on extended classroom observations and preschool teacher interviews. Results: In 90,3% of the classrooms the acceptance of diversity and inclusion of Mapuche language and culture was promoted to an inadequate or minimal degree. Nevertheless, the results were significantly more favorable for public EE compared to private-subsidized EE. Conclusion: The findings provide new evidence of the urgent need to improve the intercultural education for preschool children in interethnic contexts in Chile to impede the invisibilization of indigenous culture and devaluation of indigenous knowledge.Introducción: En contextos indígenas el derecho humano de la transmisión intergeneracional de la cultura y lengua no siempre está garantizado. Este estudio investigó en qué grado se implementaron prácticas pedagógicas para promover la aceptación de la diversidad e inclusión de la cultura y lengua Mapuche en 62 aulas preescolares compartidas por niños indígenas Mapuche y niños no-indígenas en el sur de Chile, y examinó si el grado de implementación difiere entre establecimientos educacionales (EE.EE.) municipales y particulares-subvencionados. Metodología: Se utilizó una escala de calificación cuantitativa para medir el grado de promoción de la aceptación de la diversidad y de la inclusión de la diversidad étnica basado en observaciones extendidas de las aulas y entrevistas con las educadoras. Resultados: En 90.3% de las aulas se promovió la aceptación de la diversidad y la inclusión de la cultura y lengua Mapuche en un grado inadecuado o mínimo. No obstante, los resultados fueron significativamente más favorables para los EE.EE. municipales comparados con los EE.EE. particulares-subvencionados. Conclusión: Los hallazgos proveen nueva evidencia de la necesidad urgente de mejorar la educación intercultural para niños preescolares en contextos interétnicos en Chile para impedir la invisibilización de las culturas indígenas y la desvaloración de los conocimientos indígenas

Socioeconomic status, parental beliefs, and parenting practices as predictors of preschoolers' school readiness and executive functions in chile

Parental beliefs and parenting practices in early childhood are fundamental for the development of preschoolers' school readiness and executive functions. This study examined the role of socioeconomic status (SES), ethnicity, maternal self-competence, parental cognitive stimulation, and maternal supportive discipline as predictors of five-year-old preschoolers' school readiness and executive function abilities in 70 families of low-SES homes with a Chilean majority or indigenous Mapuche minority background in Chile. Additionally, the mediating role of parental beliefs and parenting practices between SES and school readiness or executive functioning respectively was investigated as suggested by the Family Stress Model. Results show that maternal supportive discipline predicted school readiness above and beyond SES and ethnicity. Furthermore, maternal supportive discipline mediated the relation between SES and school readiness, whereby higher SES positively affected maternal supportive discipline, which in turn had a favorable effect on school readiness. All other associations were non-significant. The outcomes highlight that parental involvement of culturally diverse families from low-SES backgrounds is important for children's cognitive development. School readiness of Chilean preschoolers from low-SES homes might possibly be improved by enhancing maternal sensitivity and positive behavioral control strategies. These parenting skills have the potential to mitigate the adverse effects of low-SES environments to some extent. The findings of this study inform interventions integrated into early childhood education programs. (c) 2021 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/

Preschoolers' problem behavior, prosocial behavior, and language ability in a Latin-American context: The roles of child executive functions and socialization environments

Child executive functions and socialization environments are crucial for the socioemotional and cognitive development of preschoolers. This study examined the role of socioeconomic status (SES), ethnicity, executive functions (EFs), quality of the home environment, quantity of maternal care, and quality and quantity of professional childcare as predictors of five-year-old preschoolers' problem behavior, prosocial behavior, and language ability in 77 low-SES families with a Chilean majority or Mapuche minority background in Chile. Executive functions and the quality of the home environment were positively associated with language ability, whereas quantity of childcare was inversely related to children's language ability. All other associations were non-significant. The results corroborate the vital roles of child executive functioning and stimulating and responsive parenting in child language ability in a Latin-American context. Furthermore, our findings revealed inadequate preschool classroom quality and provide new evidence from southern Chile of the urgent need to improve the quality of Chilean children's preprimary education as a catalyst for reducing social disparities. (C) 2019 Published by Elsevier Inc.Development Psychopathology in context: famil

Preschoolers' problem behavior, prosocial behavior, and language ability in a Latin-American context: The roles of child executive functions and socialization environments

Child executive functions and socialization environments are crucial for the socioemotional and cognitive development of preschoolers. This study examined the role of socioeconomic status (SES), ethnicity, executive functions (EFs), quality of the home environment, quantity of maternal care, and quality and quantity of professional childcare as predictors of five-year-old preschoolers' problem behavior, prosocial behavior, and language ability in 77 low-SES families with a Chilean majority or Mapuche minority background in Chile. Executive functions and the quality of the home environment were positively associated with language ability, whereas quantity of childcare was inversely related to children's language ability. All other associations were non-significant. The results corroborate the vital roles of child executive functioning and stimulating and responsive parenting in child language ability in a Latin-American context. Furthermore, our findings revealed inadequate preschool classroom quality and provide new evidence from southern Chile of the urgent need to improve the quality of Chilean children's preprimary education as a catalyst for reducing social disparities. (C) 2019 Published by Elsevier Inc