Use of numerical and spatial information in ordinal counting by zebrafish

The use of non-symbolic numerical information is widespread throughout the animal kingdom, providing adaptive benefits in several ecological contexts. Here we provide the possible evidence of ordinal numerical skills in zebrafish (Danio rerio). Zebrafish were trained to identify the second exit in a series of five identically-spaced exits along a corridor. When at test the total length of the corridor (Exp. 1) or the distance between exits (Exp. 2) was changed, zebrafish appeared not to use the absolute spatial distance. However, zebrafish relied both on ordinal as well as spatial cues when the number of exits was increased (from 5 to 9) and the inter-exit distance was reduced (Exp. 3), suggesting that they also take into account relative spatial information. These results highlight that zebrafish may provide a useful model organism for the study of the genetic bases of non-symbolic numerical and spatial cognition, and of their interaction

Structural insights into Clostridium perfringens delta toxin pore formation

Clostridium perfringens Delta toxin is one of the three hemolysin-like proteins produced by C. perfringens type C and possibly type B strains. One of the others, NetB, has been shown to be the major cause of Avian Nectrotic Enteritis, which following the reduction in use of antibiotics as growth promoters, has become an emerging disease of industrial poultry. Delta toxin itself is cytotoxic to the wide range of human and animal macrophages and platelets that present GM2 ganglioside on their membranes. It has sequence similarity with Staphylococcus aureus β-pore forming toxins and is expected to heptamerize and form pores in the lipid bilayer of host cell membranes. Nevertheless, its exact mode of action remains undetermined. Here we report the 2.4 Å crystal structure of monomeric Delta toxin. The superposition of this structure with the structure of the phospholipid-bound F component of S. aureus leucocidin (LukF) revealed that the glycerol molecules bound to Delta toxin and the phospholipids in LukF are accommodated in the same hydrophobic clefts, corresponding to where the toxin is expected to latch onto the membrane, though the binding sites show significant differences. From structure-based sequence alignment with the known structure of staphylococcal α-hemolysin, a model of the Delta toxin pore form has been built. Using electron microscopy, we have validated our model and characterized the Delta toxin pore on liposomes. These results highlight both similarities and differences in the mechanism of Delta toxin (and by extension NetB) cytotoxicity from that of the staphylococcal pore-forming toxins

Selectivity of Metarhizium anisopliae and Beauveria bassiana to adults of Telenomus podisi (Hymenoptera: Scelionidae).

Título em português: Seletividade de Metarhizium anisopliae e Beauveria bassiana para adultos de Telenomus podisi (Hymenoptera: Scelionidae)

Improving financial capability: the mediating role of financial behaviour

This paper investigates the collective impact of financial literacy and inclusion on individuals’ financial capability focusing on the mediating role of financial behaviour. The research is conducted on an individual-level survey. The relationships were examined by using PLS-SEM. Financial capability can be improved by increasing individuals’ financial knowledge, financial behaviour and promoting their inclusion in financial services. Furthermore, the indirect effect of financial knowledge and attitude on financial capability is found to be significant, highlighting the importance of financial behaviour. The results assist policymakers and industry leaders in understanding the most influential factors on financial capability in the context of a post-communist transition country. This enables them to design policies and services aimed at equipping citizens with knowledge and skills to make best use of their financial resources. © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Internal Grant Agency of FaME TBU [IGA/FaME/2019/002

A produção escrita de alunos com e sem síndrome de Down: uma análise da coerência textual

Neste trabalho, analisa-se a coerência textual a partir da reescrita do conto de Rapunzel. Baseia-se em uma abordagem psicogenética da língua escrita. Participaram desse estudo nove alunos, sendo seis com síndrome de Down (Grupo I) e os outros três sem deficiência (Grupo II). Eles cursavam entre o 2º e 8º anos do Ensino Fundamental em escolas regulares. O procedimento de produção textual consistiu em um encontro individual, cuja solicitação de produção escrita era precedida pela leitura do conto pela pesquisadora. Os dados indicaram a presença da coerência textual nos dois grupos, embora mais frequente nas produções do grupo II, que demonstrava maior competência com os elementos de coerência textual. O grupo II apresentou estratégias poderosas para mobilizar os recursos cognitivos que permitiram articular conhecimentos anteriores e focalizá-los na produção e articulação de suas ideias no texto. O grupo I, na sua maioria, experimentava dificuldades em elaborar um desfecho em estreita relação com as partes que compunham o texto. Não apresentaram, porém, dificuldades em definir e manter a personagem principal ao longo de toda a história escrita, mesmo quando a história era incoerente se considerarmos outros indicadores. Qualitativamente, os textos dos alunos com síndrome de Down se diferenciaram daqueles produzidos pelo grupo II. Não identificamos, porém, características que podem representar especificidades na produção escrita dos alunos com essa síndrome, visto que alguns alunos com síndrome de Down produziram textos apresentando coerência

Skilled But Unaware of It: Occurrence and Potential Long-Term Effects of Females' Financial Underconfidence

We find strong gender- and education-related differences in the distribution of actual and perceived financial sophistication: Whereas financial literacy rises in formal education, confidence increases in education for men but decreases for women. We show that the financial decisions of highly-educated men benefit strongly from this excess confidence, while the underconfidence of highly-educated women, in contrast, impairs their long-term financial planning