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Children all over the world learn language, yet the contexts in which they do so vary substantially. This variation needs to be systematically quantified to build robust and generalizable theories of language acquisition. We compared communicative interactions between parents and their 2-year-old children (N = 99 families) during mealtime across five cultural settings (Brazil, Ecuador, Argentina, Germany, and Japan) and coded the amount of talk and gestures as well as their conversational embedding (interlocutors, function, and themes). We found a comparable pattern of communicative interactions across cultural settings, which were modified in ways that are consistent with local norms and values. These results suggest that children encounter similarly structured communicative environments across diverse cultural contexts and will inform theories of language learning.

Introduction: This paper contributes to the research on teacher burnout by distinguishing between two aspects of work demands that are usually merged in the "workload" construct: the quantity of the demands (quantitative demands) and the cognitive effort they require (cognitive demands). Such a distinction may offer insight into how educational administrators should manage certain types of work demands. Method: In an international sample of 209 kindergarten, primary and lower secondary teachers working in 110 schools from four different countries (Brazil, Chile, Ecuador, and Spain), we administered the Maslach Burnout Inventory (MBI) and the Copenhagen Psychosocial Questionnaire II (COPSOQII). We conducted three separate multiple regressions in which the work conditions (COPSOQII) were set (forced entry) as predictors of emotional exhaustion, depersonalization, and personal accomplishment (MBI). Results: We found that quantitative and cognitive demands predict teacher burnout differently: while quantitative demands predict emotional exhaustion and depersonalization, cognitive demands play a protective role in relation to those two components and also predict personal accomplishment. Additionally, we found that emotional demands positively predict emotional exhaustion and depersonalization, and negatively predict personal accomplishment. We also found that support from colleagues and community positively predicts personal accomplishment, but shows no significant relationship with either emotional exhaustion or depersonalization. Discussion and Conclusion: Results suggest that the distinction between the quantity of demands and the cognitive effort they require is meaningful and important for future research and practice in the field of teaching. One important implication for educational administration is that the quantity of work assigned to teachers should be kept relatively low but, at the same time, this work should be cognitively activating and demanding.

The plecos (Loricariidae) fish represent a great model for cytogenetic investigations due to their variety of karyotypes, including diploid and polyploid genomes, and different types of sex chromosomes. In this study we investigate Transancistrus santarosensis a rare loricariid endemic to Ecuador, integrating cytogenetic methods with specimens' molecular identification by mtDNA, to describe the the species karyotype. We aim to verify whether sex chromosomes are cytologically identifiable and if they are associated with the accumulation of repetitive sequences present in other species of the family. The analysis of the karyotype (2n = 54 chromosomes) excludes recent centric fusion and pericentromeric inversion and suggests the presence of a ZZ/ZW sex chromosome system at an early stage of differentiation: the W chromosome is degenerated but is not characterized by the presence of differential sex-specific repetitive DNAs. Data indicate that although T. santarosensis has retained the ancestral diploid number of Loricariidae, it accumulated heterochromatin and shows non-syntenic ribosomal genes localization, chromosomal traits considered apomorphic in the family. [ABSTRACT FROM AUTHOR]

Ancistrus Kner, 1854, is the most diverse genus among the Ancistrini (Loricariidae) with 70 valid species showing a wide geographic distribution and great taxonomic and systematic complexity. To date, about 40 Ancistrus taxa have been karyotyped, all from Brazil and Argentina, but the statistic is uncertain because 30 of these reports deal with samples that have not yet been identified at the species level. This study provides the first cytogenetic description of the bristlenose catfish, Ancistrus clementinae Rendahl, 1937, a species endemic to Ecuador, aiming to verify whether a sex chromosome system is identifiable in the species and, if so, which, and if its differentiation is associated with the presence of repetitive sequences reported for other species of the family. We associated the karyotype analysis with the COI molecular identification of the specimens. Karyotype analysis suggested the presence of a ♂ZZ/♀ZW1W2 sex chromosome system, never detected before in Ancistrus, with both W1W2 chromosomes enriched with heterochromatic blocks and 18S rDNA, in addition to GC-rich repeats (W2). No differences were observed between males and females in the distribution of 5S rDNA or telomeric repeats. Cytogenetic data here obtained confirm the huge karyotype diversity of Ancistrus, both in chromosome number and sex-determination systems. [ABSTRACT FROM AUTHOR]

Humans, unlike any other species, have adapted to diverse environments across the globe due to cultural knowledge, skills, and practices. In early childhood, parent–child interactions play a pivotal role in cultural learning, but controversies about what constitutes teaching have stymied the systematic assessment of variation and similarities in parental teaching across cultures. We used a functional definition of teaching as behavior that evolved to facilitate learning in others and observed parents and their two-year-old child (N = 106) in a standardized setting (mealtime) in five diverse cultural contexts (rural: Brazil, Ecuador; urban: Argentina, Germany, Japan). Detailed coding of parental teaching (8520 teaching events in 1898 min of interactions) revealed that six teaching behaviors (prompts to do, prompts to stop, abstract communication of knowledge, demonstrations, providing choices, negative feedback) occurred frequently (> 5%) across contexts. At the same time, we found that the relative frequencies of these behaviors varied between contexts: Parents in rural contexts frequently used prompts towards their children. Parents in urban contexts often used abstract communication, demonstrations, and the provision of choices. We also identified nuanced differences between the urban samples regarding parental demonstrations (Japan) and the provision of choices (Germany). Our findings suggest that parents from all contexts mainly relied on a set of six teaching behaviors but that there was cross-cultural variation in how frequently behaviors occurred. Our study provides a cultural map of children's early learning experiences which lay the ontogenetic foundation for human cultural diversity. [ABSTRACT FROM AUTHOR]

Objective. To synthesize the findings on correlates of physical activity (PA) and sedentary behavior (SB) in South American children. Method. A search was carried out from June 24 to October 27, 2020, in the LILACS, PubMed, SciELO, Scopus and Web of Science databases. To broaden the search, the references of identified review articles were examined, and a panel of experts was surveyed. Observational and interventional studies conducted with South-American children from zero to 5 years of age were included. Results. Of 3 111 articles initially identified, 18 were eligible: 14 observational studies, 12 studies conducted in Brazil, and 17 studies investigating preschool children (3 to 5 years of age). In addition to Brazil, only Chile and Ecuador were represented. PA and SB were measured by accelerometers in seven studies; however, high variability was observed in the instruments and cut-off points used. Although children were classified as physically active in 12 studies, six studies showed that they spent considerable time in SB. Most studies assessed the individual (14 studies) and interpersonal (11 studies) domains, followed by the environmental (eight studies) and political (one study) domains. Interventions in the school context (four studies) increased PA levels and reduced the time spent in SB. However, the evidence from cross-sectional and interventional studies presented a high risk of bias. Conclusions. Given the knowledge gap identified in this review, studies with robust designs, covering additional South American countries are warranted, focusing on infants and children under 3 years of age and investigating correlates in the environmental and political domains. [ABSTRACT FROM AUTHOR]