ABSTRACT A significant portion of the current knowledge regarding the use of iron nanoparticles for remediating metal-contaminated soils is derived from laboratory experiments, leaving several unanswered questions. This article presents a field experiment comparing the efficacy of magnetite nanoparticles and microparticles for the immobilization of metals and the growth of plants in metal-contaminated soils. This study aimed to investigate the effects of magnetite particle size on metal immobilization and plant growth in soils exposed to airborne pollution from the Middle-Urals Copper Smelter in the southern taiga subzone near Revda, Russia, 50 km from Ekaterinburg. Magnetite nano- and microparticles were added to forest litter at a 4 % w/w dose. The total metal contents in litter from the study plots were 1-2 orders of magnitude higher than background metal concentrations. The magnetite nanoparticle treatment was found to decrease the concentration of exchangeable copper in soil and improve the growth of red fescue (Festuca rubra L.) on polluted soil compared to the control. In contrast, magnetite microparticles did not show any statistically significant effects. These findings are in line with laboratory results that demonstrated the superior metal adsorption properties of magnetite nanoparticles compared to microparticles. However, this study was limited in duration (2 months), and longer field studies would be necessary to confirm the role of iron particle size in the rehabilitation of metal-contaminated soils.

Abstract: Intellectual disability (ID) is a neurodevelopmental disorder characterized by limitations in intellec tual and adaptive functioning, of various etiologies, including genetic causes. Objective: to describe genetic studies carried out in a series of children and adolescents with ID of previously undetermined etiology, considering their phenotypic characteristics. Patients and Method: Descriptive study of a series of patients with ID aged 6 to 18 years. Clinical records, cognitive assessment results (Wechsler -TADI), and genetic study performed were reviewed. They were classified according to phenotypic characteristics into Group 1 patients without a specific phenotype, Group 2: patients with Angel- man- and Rett-like neurodevelopmental disorders phenotype, and Group 3: patients with difficult- to-control seizures. Group 1 was studied with CMA and Groups 2 and 3 with specific genetic panels. Results: 18 patients were described, average age 11 years, male predominance, non-consanguineous parents, and with history of psychomotor retardation. Common comorbidities were epilepsy, autism spectrum disorder (ASD), and behavioral difficulties. Most had a neurological examination without focus and had TADI with very poor developmental ages. In Group 1, there was one patient with a 16p11.2 microdeletion and in Group 3 a duplication of the IQSEC2 gene was found in a patient with difficult-to-control seizures. Conclusions: The phenotypic characteristics allow to guide the choice of specific genetic studies in children and adolescents with ID of previously undetermined etiology to approach the etiological diagnosis.

Resumen: Introducción: La discapacidad intelectual (DI) es un trastorno del neurodesarrollo manifestado por limitaciones en el funcionamiento intelectual y adaptativo, de etiologías diversas, dentro de las cuales se incluyen las causas genéticas. Objetivo: Describir estudios genéticos realizados en una serie de niños y adoles centes con DI de etiología previamente indeterminada, considerando sus características fenotípicas. Pacientes y Método: Estudio descriptivo de una serie de pacientes con DI de 6 a 18 años. Se revisaron registros clínicos, resultados de evaluación cognitiva (Wechsler-TADI) y estudio genético realizado. Se clasificaron según características fenotípicas en: Grupo 1 pacientes sin fenotipo específico, Grupo 2: pacientes con fenotipo de desórdenes del neurodesarrollo Angelman-Rett like y Grupo 3: pacien tes con epilepsia de difícil manejo. Grupo 1 se estudió con microarray cromosómico y Grupos 2 y 3 con paneles genéticos específicos. Resultados: Se describen 18 pacientes, edad promedio 11 años, predominio sexo masculino, de padres no consanguíneos, con antecedente de retraso psicomotor. Comorbilidades frecuentes: epilepsia, rasgos de trastorno espectro autista (TEA) y dificultades conductuales. La mayoría tuvo examen neurológico sin focalidad y TADI con edades de desarrollo muy descendidas. En Grupo 1 se diagnosticó un paciente con una microdeleción 16p11.2 y en Grupo 3 se diagnosticó una duplicación del gen IQSEC2, en un paciente epiléptico de difícil manejo. Conclu siones: Las características fenotípicas permiten orientar la elección de estudios genéticos específicos en niños y adolescentes con DI de etiología previamente indeterminada para acercarse al diagnóstico etiológico.

Abstract: The article presents insights of an ongoing research on the experiences and perceptions of young people about work in the context of the social and sanitary crisis, crossed by the October uprising and the outbreak of the current COVID-19 pandemic. As a data collection method, semi-structured, online interviews were applied to young people with work experience. By means of a content analysis, it is intended to highlight the most common perceptions and preliminary findings towards this work: the search for independence from a family context, the different meanings of work for young people, and the emergence of household work as a more prominent reality for young women.

Resumen: El artículo presenta avances de la investigación en curso sobre las experiencias y percepciones de jóvenes en torno al trabajo en contexto de crisis sociosanitaria, cruzada por la revuelta de octubre y la irrupción de la actual pandemia por Covid-19. Se aplicaron entrevistas semiestructuradas en formato virtual a jóvenes con experiencia laboral. Por medio de un análisis de contenido se buscó relevar las percepciones más comunes, tales como la búsqueda de independencia respecto a lo familiar, los diferentes significados del trabajo en jóvenes y la emergencia del trabajo doméstico como una realidad que se ha intensificado también en el caso de las mujeres jóvenes; constituyendo estos los hallazgos preliminares del estudio.

Resumo: O artigo apresenta avanços da pesquisa em andamento sobre as experiências e percepções dos jovens sobre o trabalho no contexto da crise social e sanitária, atravessada pela revolta de outubro e o surto da atual pandemia de COVID-19. Foram aplicadas entrevistas semiestruturadas em formato virtual a jovens com experiência profissional. Através de uma análise de conteúdo, procuramos relevar as percepções mais comuns, tais como a busca de independência da família, os diferentes significados do trabalho nos jovens e a emergência do trabalho doméstico como uma realidade que também se intensificou no caso das mulheres jovens; constituindo as descobertas preliminares do estudo.

Abstract: Introduction: Robot-assisted Therapy (RAT) can improve the behavior of children with Autism Spectrum Disorder (ASD) in a spontaneous and entertaining way. There are no previous experiences of this type of inter vention in our country. Objective: To describe a clinical experience of using RAT and its impact on the behaviors of a group of children with ASD, in a therapeutic context. Patients and Method: Quasi experimental clinical experience type study. 4 children with a clinical diagnosis of ASD were selected, supported by the ADOS-2 (Autism Diagnostic Observation Schedule); aged between 9 and 13 years, and normal IQ according to the WISC-III (Wechsler Intelligence Scale for Children). This study was approved by the Central Metropolitan Ethics Committee. Patients attended 10 structured robot-as sisted therapy sessions, working collaboratively in pairs. Workshop attendance and parent and child satisfaction were evaluated through surveys, the adaptive behavior with the Vineland scale, and so cial interaction with video coding guidelines. Results: Patients presented a very good adherence and satisfaction with the activity. There was an improvement in socialization behaviors and social age. Video-coding showed an increase in social interaction and improvement in the behavior of the pa tients after attending workshops. Conclusions: We observed that the experience with RAT, adapted to the context of a Chilean public health center, was highly attractive and beneficial for patients with ASD, improving core symptoms such as difficulties in social interaction and behavioral problems.

Resumen: Introducción: Existe evidencia de que la terapia robótica (TR) puede mejorar la conducta de niños con Trastorno del Espectro Autista (TEA) de forma espontánea y entretenida. No hay experiencias previas de este tipo de intervenciones en nuestro país. Objetivo: Describir la experiencia clínica del uso de TR y su impacto en las conductas de un grupo de niños con TEA, en un contexto terapéutico. Pacientes y Mé todo: Estudio de tipo experiencia clínica cuasi-experimental. Se seleccionaron 4 niños con diagnósti co clínico de TEA, complementado con ADOS 2 (Escala Observación para Diagnóstico del Autismo); edad 9-13 años y coeficiente intelectual normal con WISC-III (Escala Wechsler Inteligencia para Niños). Aprobado por Comité de Ética Metropolitano Central. Los pacientes asistieron a 10 sesiones estructuradas de terapia robótica, trabajando en duplas de manera colaborativa. Se evaluó la asisten cia a talleres, la satisfacción de padres y niños mediante encuestas, la conducta adaptativa con escala de Vineland y la interacción social con pauta de codificación de video. Resultados: Se obtuvo una muy buena adherencia y satisfacción con la actividad. Se evidenció mejoría de conductas de sociali zación y edad social. La video-codificación mostró un incremento en la interacción social y mejoría en el comportamiento de los pacientes, luego de la asistencia a talleres. Conclusiones: Observamos que la experiencia con TR adaptada al contexto de un centro de salud público chileno fue altamente atractiva y provechosa para pacientes con TEA, mejorando síntomas ejes como son las dificultades en la interacción social y problemas conductuales.

Abstract: Introduction: The prevalence of Autism Spectrum Disorder has increased, varying between 0.5 and 1% around the world. The prevalence of ASD in Chile is unknown. Objective: To estimate the prevalence of ASD in two urban communes of Santiago, Chile. Subjects and Method: Cross-sectional epidemiological study. 272 children aged between 18-30 months who attended well-child visits at two Family Health Centers in two urban communes of Santiago participated. Consecutive sampling was used and chil dren who were already being monitored by neurology were excluded. Screening was performed using the Modified Checklist for Autism in Toddlers (M-CHAT). Those children with altered M-CHAT were evaluated by a pediatric neurologist at the San Borja Arriarán Clinical Hospital and diagnosed with ASD according to clinical criteria. The Autism Diagnostic Observation Schedule - Second Ver sion (ADOS-2) was used as a diagnostic complement. The prevalence of ASD was estimated with a 95% confidence interval. Results: 44 children had altered M-CHAT; 5 of them were clinically diagno sed with ASD. A 1.95% prevalence of ASD (95% CI 0.81-4.63) was obtained, with a sex distribution of 4 boys per 1 girl. Conclusions: This study is the first estimate of ASD prevalence in two communes of Santiago, Chile. A high prevalence of this condition was observed, which highlights the need for obtaining resources for an early multidisciplinary approach for these patients.

Resumen: Introducción: La prevalencia del Trastorno del Espectro Autista ha aumentado, variando entre 0,5 y 1% alrededor del mundo. Se desconoce la prevalencia de TEA en Chile. Objetivo: Estimar la prevalencia de Tras torno del Espectro Autista en 2 comunas urbanas de Santiago de Chile. Sujetos y Método: Estudio epidemiológico transversal. Participaron 272 niños entre 18-30 meses que asistían a control sano en dos Centros de Salud Familiar de dos comunas urbanas de la capital. Se utilizó un muestreo con secutivo y se excluyeron los niños que ya estaban siendo controlados por neurología. Se realizó un tamizaje mediante el Cuestionario de Autismo en Niños - Modificado (MCHAT). Los niños con M- CHAT alterado fueron evaluados por neuropediatra en el Hospital Clínico San Borja Arriarán y diag nosticados con Trastorno del Espectro Autista de acuerdo a criterio clínico. Se administró la Escala de Observación para el Diagnóstico del Autismo - Segunda Versión (ADOS-2) como complemento diagnóstico. Se estimó la prevalencia de Trastorno del Espectro Autista con intervalo de confianza al 95%. Resultados: 44 niños tuvieron M-CHAT alterado; de ellos 5 fueron diagnosticados clínicamen te con Trastorno del Espectro Autista. Se obtuvo una prevalencia de Trastorno del Espectro Autista de 1,95% (IC95% 0,81-4,63), con una distribución por sexo de 4 niños por 1 niña. Conclusiones: Esta es la primera estimación de prevalencia de Trastorno del Espectro Autista en dos comunas de Santiago, Chile. Se obtuvo una alta prevalencia de esta condición, lo que deja en evidencia la necesi dad de obtener recursos para el abordaje multidisciplinario precoz de estos pacientes.

ABSTRACT The concept of attitude toward soil is emerging, with a slim choice of scales available to collect hard data. There is also a dearth of standard scales to acquire precise data on students’ knowledge of soil. Therefore, the objectives of the present study were: (1) to devise appropriate scales to quantify theoretical soil knowledge and attitude toward soil, and (2) to quantify the effect of laboratory studies and fieldwork on students’ theoretical soil knowledge and attitude toward soil. The study is based on data collected from undergraduate students of the introductory soil science course. Participating students were randomly divided into two groups. Teaching of the control group (n = 38) was classroom-based, while teaching of the intervention group (n = 43) was complemented with laboratory studies and fieldwork. Our test design included a pre-test and post-test. It appears that theoretical soil knowledge and students’ attitude toward soil can be improved using classroom-based education alone, without any need for laboratory or field components. However, future studies would be needed to develop questionnaires covering hands-on soil knowledge to better gauge the impact of lab work and field classes on student learning. The present study is an important step to elaborate reliable scales suitable for quantifying students’ knowledge and attitude toward the soil. It is impossible to test academic assumptions or create theoretical foundations for soil science education without a reliable device to weigh analytical concepts.

The species of subfamily Papilionoideae present flowers with a complex architecture, with elaborated petals in which it has been documented the presence of auricles and callosities, appendixes or spurs that joint the pieces of the corolla and also microsculpturings on the wings. In this study, we analyze the morphology of the petals of 17 species of Papilionoideae (Leguminosae) native of Salta province, Argentina. The lower margins of the keel were fused in all of the species, through different types of fusion of epidermal cells. Only a few species presented fusion in the upper margin of the keel. All the species showed sculpturings in the petals, which would joint some of the pieces of the corolla. They also exhibit ornaments or microsculpturings in the basal region of the adaxial surface of the wings that may act as a grip for pollinators when they land on the flower. The petals of the Papilionoideae flowers presented characteristics that could restrict the type of pollinator able to activate the different mechanisms of pollination that allow them to access the rewards enclosed by the keel.

Las flores de la subfamilia Papilionoideae tienen una arquitectura compleja con pétalos elaborados, en los que se ha observado la presencia de aurículas o callosidades, apéndices o espolones que articulan las piezas entre sí y de ornamentaciones principalmente en las alas. En este trabajo se analizó la morfología de las piezas de la corola de 17 especies de Papilionoideae (Leguminosae) nativas de la provincia de Salta. Todas las especies presentaron fusión entre los márgenes inferiores de la quilla que involucraba diferentes tipos de uniones a nivel de las células epidérmicas. Solo algunas de las especies estudiadas presentaron fusión en los márgenes superiores de la quilla. Todas las especies presentaron esculturas en los pétalos que servirían para articular las piezas de la corola entre sí. También presentaron ornamentaciones o microesculturaciones ubicadas en la región basal de la cara adaxial de las alas, que favorecerían el sostén de los visitantes al posarse sobre ellas. Los pétalos de las flores de Papilionoideae presentaron características que podrían restringir el tipo de polinizador capaz de activar los distintos mecanismos de polinización que le permiten acceder a las recompensas encerradas por la quilla.

Microbiological bioassays of nitrification and nitrogen mineralization have been used for evaluation of soil quality on metal-contaminated soils. We evaluated the effectiveness of nitrification and nitrogen mineralization bioassays as quality indicators of soil degradation caused by metal contamination. We performed standard tests based on protocols of ISO 14238 (2012) and ISO 15685 (2012) on 90 soil samples collected from agricultural areas in central Chile that were historically contaminated by mining activities. Potential nitrification rate (PNR) was best explained by pH and organic matter content (OM) (R²=0.32), while nitrogen mineralization (Nmin) was best explained by OM and clay content (R²=0.44). Following normalization of the bioassays responses with respect to OM yielded significant correlations between PNR and pH and total Cu content (R²=0.22), and between Nmin and clay and total Cu contents (R²=0.19). However, inasmuch as total Cu content improved the regression model showing the inhibitory effect of Cu in both bioassays, it accounted for a mere small proportion of the variance. This was despite the wide range of Cu contents in the soils studied (51-2878 mg kg-1). Hence, due to the known sensitivity of the nitrification and nitrogen mineralization process to physicochemical characteristics of soils, these bioassays seem to have limited applicability for metal toxicity assessment in metal-contaminated soils.