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Cover: Flowering on the trunk of the jabuticaba tree.
Author: Gobato, M.R.R. (2025) Flowering of the jabuticaba tree. 86130.000, Brazil.
Coordinates: -22.997001, -51.196352
A jaboticaba or jabuticaba (Portuguese: is a round, edible fruit produced by a jaboticaba tree (Plinia cauliflora), also known as Brazilian grapetree. The purplish-black, white-pulped fruit grows directly on the trunk of the tree, making it an example of 'cauliflory'. It is eaten raw or used to make jellies, jams, juice or wine. The tree, of the family Myrtaceae, is native to the states of Rio de Janeiro, Minas Gerais, Goiás and São Paulo in Brazil. Related species in the genus Myrciaria, often referred to by the same common names, are native to Brazil, Argentina, Paraguay, Peru and Bolivia. Source:
https://www.sciencepublishinggroup.com/article/10.11648/j.larp.20180301.11
Cabo Transformador Elétrico (Mini-revisão)
Vladimir Nikolaevich Sukhanov
Parana J. Sci. Educ., v.11, n.5, (1-5), October 12, 2025.
Abstract
The operation of new electrical transformer cables is based on the principle of induction of electromotive force in an electrical conductor surrounded by a magnetic circuit. With the new arrangement of winding (or windings) in the form of cable conductors with a jacket, together performing the functions of the magnetic and protective parts of the transformer, the electrical transformer cable performs two functions: an electrical transformer and an electrical cable. In this case, the cost of a dual-use transformer cable is only the cost of one transformer or the cost of one shielded cable, which in this case is the same thing. The materials that make up the transformer are dual–use: one material is used both to perform the functions of the magnetic core and to perform the functions of the protective sheath (jacket) of the cable. As a result, combined shells–magnetic cores can be made from the same material with sufficient mechanical and magnetic properties.
Resumo
O funcionamento de novos cabos de transformadores elétricos baseia-se no princípio da indução de força eletromotriz em um condutor elétrico envolto por um circuito magnético. Com o novo arranjo do enrolamento (ou enrolamentos) na forma de condutores de cabo com capa, desempenhando em conjunto as funções das partes magnética e de proteção do transformador, o cabo do transformador elétrico desempenha duas funções: um transformador elétrico e um cabo elétrico. Nesse caso, o custo de um cabo de transformador de dupla utilização é apenas o custo de um transformador ou o custo de um cabo blindado, que neste caso são a mesma coisa. Os materiais que compõem o transformador são de dupla utilização: um material é usado tanto para desempenhar as funções do núcleo magnético quanto para desempenhar as funções da capa protetora do cabo. Como resultado, núcleos magnéticos combinados com capas podem ser feitos do mesmo material com propriedades mecânicas e magnéticas suficientes.
Download: Article (in Portuguese)
Group-Based Mud Crab (Scylla serrata) Culture and Fattening for Sustainable Livelihoods of Coastal Communities of Bangladesh
Prabal Barua and Nahida Nargis
Parana J. Sci. Educ., v.11, n.5, (6-15), October 12, 2025.
Abstract
Mud crab (Scylla serrata) fattening has emerged as a promising aquaculture practice in coastal Bangladesh, offering a sustainable solution to pressing issues such as youth unemployment, underutilized coastal resources, and growing global demand for premium seafood. Despite its export potential and ecological advantages, this sector remains underexploited, particularly among educated but unemployed youth. This paper presents a conceptual model for group-based mud crab fattening that integrates biological, ecological, and socio-economic dimensions to promote entrepreneurship and inclusive livelihoods. Targeting regions such as Khulna, Satkhira, Bagerhat and Patuakhali - where brackish water conditions favor mud crab growth - the model advocates for cooperative farming among youth groups, supported by technical training, shared infrastructure, and partial public or donor investment. Key features of the model include the formation of gender-inclusive youth groups (20-25 members per union), establishment of demonstration ponds, and periodic performance monitoring to ensure scalability. A financial simulation reveals that profitability becomes sustainable from the very first cycle, following initial infrastructure investment. The approach contributes to the national Blue Economy goals by converting job seekers into aquapreneurs and promoting sustainable resource management. It aligns with global sustainable development goals (SDGs), particularly SDG 1 (No Poverty), SDG 5 (Gender Equality), SDG 8 (Decent Work and Economic Growth), SDG 13 (Climate Action), and SDG 14 (Life Below Water).The model also addresses potential risks such as climate vulnerability and access to capital by recommending strategic interventions, including microfinance support and capacity-building programs. This framework provides a scalable, community-driven path for revitalizing coastal livelihoods and strengthening Bangladesh’s position in the international aquaculture market.
Download: Article (in English)
Estudo preliminar de desenhos de insetos na pré-escola (Estudo de Caso)
Amauri Betini Bartoszeck and Marianna Canova
Parana J. Sci. Educ., v.11, n.5, (16-20), October 12, 2025.
Abstract
Children from Southern Brazil schools have a basic knowledge of the external structure of insects they see in everyday life. Pupils from 4 to 6 years old were asked to draw what they think is na insect. Pictures were analised according to contents. Educational implications are discussed. Children from a pre-school in the city of Curitiba, Paraná, Brazil were studied.
Resumo
Crianças de escolas do Sul do Brasil têm um conhecimento básico da estrutura externa de insetos que elas encontram no cotidiano. Aos alunos de 4 a 6 anos de idade lhes foi pedido para desenharem o que acham que seja um inseto. Os desenhos foram analisados sob o ponto de vista de conteúdo. São discutidas aplicações educacionais. Foram estudas as crianças de uma pré-escola da cidade de Curitiba, Paraná, Brasil.
Download: Article (in Portuguese)
On Ekeland Variational Principle in Asymmetric b-Metric Spaces
Anas Yusuf and Junaidu Nafiu Mallam
Parana J. Sci. Educ., v.11, n.5, (21-27), October 12, 2025.
Abstract
This paper extends the Ekeland Variational Principle (EVP) to the setting of asymmetric b-metric spaces, which generalize both asymmetric metric and b-metric spaces. By distinguishing forward, backward and bi-completeness, we establish corresponding forward, backward and bi-complete version of EVP. Examples are provided to demonstrate that forward and backward principles may yield different minimizers while the bi-complete EVP reduces to the classical EVP when symmetry holds. As an application, we obtain a forward and backward Cartisi-type fixed point theorem. These results broaden the scope of EVP and offer a new tools for optimization and fixed-point theory in asymmetric frameworks.
Download: Article (in English)
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