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Countervailing impacts of fossil fuel production and exports of electrical goods on energy transitions and climate change.
No full textWe analyze the implications of fossil fuel production by the U.S. and increasing exports of electrical goods by China on critical mineral prices, energy transitions, and climate change. Using a GVAR model from July 2012 to December 2019, encompassing 12 economies, we employ the dominant unit model and structural identification of shocks. Our findings reveal that increased U.S. fossil fuel production leads to a rise in global CO2 emissions, hampers domestic energy transitions, and triggers changes in critical mineral markets. Fossil fuel emerges as the primary external factor influencing national energy matrices and carbon emissions, highlighting spillover effects from the U.S. energy matrix on the global economy. While U.S. fossil fuel production negatively impacts energy transitions over the long term, Chinese exports of electrical goods contribute to cleaner energy production. These countervailing forces suggest that the global transition to clean energy may occur, but it will be slow. We discuss policy implications, which should: i) promote international trade by reducing protectionist policies and establishing multilateral or bilateral agreements; ii) incentivize the adoption of clean energy; and iii) diminish the incentive to use fossil fuel energy through fiscal and tax policies
Development and validity evidence on the scale of perceived social support for university students (EPSSEU) during the period of social restrictions.
No full textAim: This study aims to validate a Perceived Social Support Scale for University Students (EPSSEU) during periods of social restrictions, by focusing on family and university support.
Subject and methods: This cross-sectional study was conducted with undergraduate students from a public higher education institution. The college students who participated in the study—1353 at baseline and 378 after 6 months— answered a virtual questionnaire containing questions on: sociodemographic and lifestyle data, items proposed for the EPSSEU, Satisfaction with Social Support Scale (ESSS), and Depression, Anxiety and Stress Scale (DASS-21). Exploratory factor analysis, Cronbach’s alpha reliability analysis, as well as discriminant, convergent, and known-group validations were performed.
Results: The results showed two factors support from: i) the university and ii) friends and family— which explained 61.82% of the variance in the data. The EPSSEU showed good reliability (Cronbach’s alpha = 0.796) as well as validity, with higher scores among individuals without depression, anxiety, or stress.
Conclusion: The EPSSEU shows adequate psychometric qualities and may be a useful instrument for assessing university students’ social support in pandemics, social distancing, and remote teaching contexts
The Lareira de Nazaré Association and the importance of volunter work.
No full textO presente artigo tem a finalidade de divulgar o trabalho da Associação Lareira de Nazaré, uma entidade sem fins lucrativos fundada no final da década de 60 por senhoras que visavam ajudar a comunidade. A Lareira foi criada com o objetivo de proporcionar amparo às pessoas carentes em situação de risco social. Além disso, ela promoveu eventos socioculturais cuja renda foi revertida para a Santa Casa de Misericórdia de Ouro Preto, para o Asilo São Vicente de Paulo, e outras associações filantrópicas. Realizou
também oficinas e palestras que trataram de assuntos como economia doméstica, artesanato, alimentação saudável, amamentação e qualidade de vida. A Associação possui sede própria, com dois andares, onde são desenvolvidas a maior parte de suas atividades e está legalmente constituída. O papel do Projeto de Extensão foi integrar os alunos da Universidade Federal de Ouro Preto a essa ação, colaborando na divulgação
do trabalho, além de buscar visibilidade para o projeto, pois cada vez mais suas atividades estão ameaçadas de extinção devido à escassez de senhoras para dar continuidade. A partir da análise histórica e das reuniões semanais das associadas, percebeu-se que o papel social da Lareira de Nazaré vai muito além do que sua finalidade preceituada.This article aims to disseminate the work of the Fireplace of Nazareth Association, a non-profit organization founded in the late 1960s by ladies who aimed to help the community. The Fireplace was created with the objective of providing support to people in need in situations of social risk. In addition, she promoted sociocultural events whose income was reverted to the Santa Casa de Misericórdia de Ouro Preto, to the Asilo São Vicente de Paulo, and other philanthropic associations. He also held workshops and
lectures that dealt with issues such as home economics, crafts, healthy eating, breastfeeding and quality of life. The Association has its own headquarters, with two floors, where most of its activities are developed and is legally constituted. The role of the Extension Project was to integrate the students of the Federal University of Ouro Preto to this action, collaborating in the dissemination of the work, in addition to seeking visibility for the project, because more and more its activities are threatened with extinction due to the scarcity of ladies to continue. From the historical analysis and
weekly meetings of the associates, it was perceived that the social role of the Fireplace of Nazareth goes far beyond its preceituated purpose
Anaerobic co-digestion of brewery wastewater and aqueous phase from hydrothermal co-liquefaction of brewer’s spent grain and microalgae.
No full textAqueous phase (AP) from hydrothermal liquefaction (HTL) is an effluent with a high concentration of organic compounds
which exhibits potential for application in anaerobic digestion (AD) systems. However, inhibitory compounds present in
this effluent make it difficult to produce biogas. Hence, anaerobic co-digestion (co-AD) is an alternative for diluting the
inhibiting compounds in the reactor and, consequently, ensure methane production. In this sense, the aim of this study
was to evaluate the methane production from the anaerobic co-digestion of brewery wastewater (BW) and the AP result-
ing from the hydrothermal co-liquefaction (co-HTL) of brewer’s spent grain (BSG) and algal biomass. Therefore, AD
experiments were carried out using different proportions of BW and AP under controlled temperature (37 °C) and agita-
tion conditions (180 rpm). In this way, a two-component (BW and AP) extreme vertices design was employed to evaluate
the effects of BW and AP and their interactions on the cumulative methane (CH4) production – NmL CH4.kg COD−1
via
co-AD and to model the CH4 production aiming performer a Monte Carlo Simulations (MCS) with 10,000 interactions
to evaluate the no-CH4 production risk due AP composition (up to 5, 10, 15, 20 and 25%) on co-AD. The results proved
that the potential to inhibit (CH4) production increases as the proportion of AP in the co-AD increases. However, MCS
has demonstrated that it is possible to minimize the risks of process failure (no-CH4 production) by controlling the propor-
tion of AP in the co-AD mixture. The simulations demonstrated a risk of failure of 21.83, 16.66, 8.40, and only 1.29%
of failure (i.e. no-CH4 production) in scenarios considering AP proportion up to 25, 20, 15 and 10% respectively in the
co-AD, respectively. The results indicate using up to 10% AP in the co-AD mixture to ensure CH4 production
Análise microfaciológica e diagenética dos dolomitos e fosforitos da formação bocaina – faixa Paraguai Sul, Mato Grosso do Sul.
No full textPrograma de Pós-Graduação em Evolução Crustal e Recursos Naturais. Departamento de Geologia, Escola de Minas, Universidade Federal de Ouro Preto.Nos últimos anos, o interesse pelo estudo de rochas dolomíticas e fosfáticas cresceu significativamente. A gênese dos dolomitos ainda é considerada um enigma para a comunidade científica, principalmente devido à dificuldade em sintetizar o mineral em laboratório. Além de sua importância econômica, os fosforitos possuem grande relevância para estudos acerca de evolução sedimentar e da química dos oceanos. Recentemente, as minerações EDEM e HORII, localizadas na região da Serra da Bodoquena - MS, realizaram furos de sondagem com testemunhos para prospecção de fosfatos, que resultaram na recuperação de registros de subsuperfície inéditos da Formação Bocaina e com excelente preservação, abrindo a oportunidade para discussão dos processos de evolução diagenética. Neste trabalho, foram analisadas 42 lâminas delgadas, provenientes destes testemunhos, com foco na descrição de microfácies, evolução diagenética e reconstrução paleoambiental. Apesar do intenso processo de dolomitização e fosfatização, foi possível caracterizar treze microfácies, incluindo nove carbonáticas, três fosfáticas e uma siliciclástica. A partir das análises texturais, inferiu-se que a sucessão estudada é registro de uma plataforma orlada com frequente retrabalhamento. Os processos que acarretaram a evolução diagenética desta sucessão desenvolveram-se nos estágios sin-sedimentar, eodiagenético e mesodiagenético, atuando desde a deposição dessas rochas até o seu soterramento efetivo, sendo os mais relevantes a fosfogênese e a dolomitização. Levando em consideração o contexto paleoambiental, o modelo de dolomitização escolhido foi o de refluxo por infiltração. Por fim, utilizando o gráfico de Mazzulo (2000) que apresenta zonas de agrupamentos de dolomitas e suas origens a partir de valores isotópicos, interpretou-se que formação das rochas da Formação Bocaina ocorreu entre as zonas de sulfato redução e metanogênese.In the last years, interest in the study of dolomitic and phosphatic rocks has significantly increased. The genesis of dolomites is still considered an enigma for the scientific community, mainly due to the difficulty in synthesizing the mineral in the laboratory. In addition to their economic importance, phosphorites are highly relevant for studies on sedimentary evolution and ocean chemistry. Recently, the EDEM and HORII mining companies, located in the Serra da Bodoquena region - MS, conducted drilling with drill core samples for phosphate prospecting, resulting in the recovery of unprecedented subsurface records of the Bocaina Formation, with excellent preservation, opening up the opportunity for discussion of diagenetic evolution processes. In this work, 42 thin sections from these drill cores were analyzed, focusing on the description of microfacies, diagenetic evolution, and paleoenvironmental reconstruction. Despite the intense dolomitization and phosphatization process, it was possible to characterize thirteen microfacies, including nine carbonatic, three phosphatic, and one siliciclastic. From textural analyses, it was inferred that the studied succession is a record of a rimmed shelf with frequent reworking. The processes that led to the diagenetic evolution of this succession developed in the syn- sedimentary, eodiagenetic, and mesodiagenetic stages, acting from the deposition of these rocks to their effective burial, with the most relevant being phosphogenesis and dolomitization. Considering the paleoenvironmental context, the chosen dolomitization model was seepage-reflux. Finally, using Mazzulo's (2000) graph presenting dolomite clustering zones and their origins from isotopic values, it was interpreted that the formation of rocks from the Bocaina Formation occurred between the sulfate reduction and methanogenesis zones
Fake news about Covid-19 : dialogical relationships between persuasion techniques and legitimacy and credibility effect.
No full textAnalisam-se neste artigo relações dialógicas entre técnicas de persuasão e efeitos de legitimidade em uma notícia falsa da plataforma YouTube. A análise fundamenta-se nas contribuições sobre dialogismo e processos de significação do Círculo de Bakhtin, e a metodologia considera relações entre ideologia e realidade material do signo, signo e formas concretas da comunicação, e comunicação e base material, como indicadas por Volóchinov. Os resultados evidenciam técnicas de persuasão classificadas como humor, representação falsa, apelo à autoridade e apelo emocional, que foram articuladas para negar a principal interpretação social da propagação comunitária da covid-19 e para fortalecer a ideia de que o número de óbitos oficial era falso.This article examines the dialogic relations between persuasion techniques and legitimacy effects in a fake news item on the YouTube platform. The analysis is grounded in contributions regarding dialogism and processes of signification from Bakhtin's Circle. The methodology considers relationships between ideology and the material reality of signs, signs and concrete forms of communication, and communication and material base, as indicated by Volóchinov. The primary findings highlight persuasion techniques categorized as humor, false representation, appeal to authority, and emotional appeal, which were employed to refute the social interpretation of the community spread of COVID-19 and to bolster the idea that the official death toll was false
A toponímia de Mariana e de seus distritos : estudo de um patrimônio léxico-histórico-cultural.
No full textPrograma de Pós-Graduação em Letras. Departamento de Letras, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.Este trabalho é dedicado ao estudo da toponímia de Mariana e de seus distritos, um campo que procura documentar e preservar o patrimônio léxico-histórico-cultural presente nos nomes de lugares dessa região. Para alcançar esse objetivo, uma abordagem metodológica foi empregada, combinando técnicas de pesquisa de campo, análise documental e revisão bibliográfica. A pesquisa de campo merece destaque nesta jornada, pois proporcionou um mergulho na história oral e na memória coletiva da comunidade local. As entrevistas realizadas com os moradores mais antigos enriqueceram a compreensão sobre a origem e o significado dos topônimos, trazendo à tona narrativas. Além disso, a investigação de fontes documentais e bibliográficas permitiu uma contextualização histórica e sociocultural dos topônimos, revelando os traços de uma identidade singular que emerge do espaço geográfico. Ademais, os vínculos estabelecidos entre a grafia dos topônimos e a Linguística Histórica revelaram um trabalho importante. A análise e a classificação dos topônimos, à luz do modelo proposto por Dick (1990), mostraram- se um percurso entre tradição e inovação. De modo similar, a identificação dos oniônimos e a sua relação com a toponímia local e com a toponímia pretérita abriram novas perspectivas para compreender o vínculo entre o espaço físico e a identidade cultural. Outro achado foi a presença dos antropotopônimos, cujas histórias resgatam figuras notáveis do passado, imortalizando-as no presente a partir dos topônimos. Os resultados obtidos vão muito além de dados e estatísticas: eles representam a riqueza cultural e a ancestralidade enraizada nos topônimos de Mariana e de seus distritos. Desse modo, esta pesquisa destaca uma herança que merece ser reconhecida e valorizada.This thesis presents the study of the toponymy of Mariana and its villages, a broad field that seeks to document and preserve the lexical, historical, and cultural heritage within the names of places in this region. To achieve this objective, a methodological approach was employed, combining field research techniques, document analysis and bibliographic review. Field research is particularly noteworthy in this journey, as it provide a deep dive into the oral history and collective memory of the local community. The interviews carried out with the oldest dwellers enriched the understanding of the origin and meaning of the toponyms, bringing to light valuable narratives. In addition, the investigation of documentary and bibliographic sources allowed for a historical and sociocultural contextualization of the toponyms, revealing the traces of a singular identity that emerges from geographic space. Moreover, the connections established between the spelling of the toponyms and Historical Linguistics revealed exceptional work. The analysis and classification of toponyms, in light of the model proposed by Dick (1990), showed a journey between tradition and innovation. Similarly, the identification of ononyms and their relationship with local toponymy and past toponymy provided new perspectives for understanding the connection between physical space and cultural identity. Another finding was the presence of anthropotoponyms, whose stories rescue notable figures from the past, immortalizing them in the present through toponyms. The outcomes go far beyond data and statistics: they celebrate the cultural richness and ancestry rooted in the toponyms of Mariana and its villages. Ergo, this research highlights a peculiar heritage that deserves to be recognized and valued
Outdoor fitness equipment : mapping and analysis of the structures available in Ouro Preto and districts.
No full textO presente direciona seu olhar ao espaço urbano, propondo-se fundamentalmente a refletir as práticas de lazer e a vocação das cidades. Assim, o objetivo foi mapear a ocorrência, analisar as condições de acesso, o uso e permanência do equipamento Academias ao Ar Livre no município de Ouro Preto e seus distritos. Para isso, utilizou-se como referência as 33 Fichas Catalográficas elaboradas no âmbito do Projeto Extensionista Esporte e Lazer Ouro-pretano (ELO), que foram apreciadas a partir da técnica de análise documental. A investigação apontou a existência de 33 equipamentos, os quais não atendem aos requisitos de segurança, acessibilidade, iluminação, circulação, sanitários, mobiliários e estrutura de permanência. Somado a isso, verificou-se que a presença desse equipamento na paisagem da cidade merece ser revista, dado que sua implementação não precedeu o desenvolvimento de projetos de intervenção, animação e/ ou educação, tampouco se deu a partir de demandas populares.The present study focuses on urban space, fundamentally aiming to reflect on leisure practices and the vocation of cities. The objective was to map the occurrence, analyze the conditions of access, usage, and permanence of outdoor fitness equipment in the municipality of Ouro Preto and its districts. To achieve this, 33 cataloging forms, developed as part of the Extension Project "Esporte e Lazer Ouro-pretano" (ELO), were used as references and examined through document analysis techniques. The investigation identified 33 pieces of equipment, which do not meet the requirements for safety, accessibility, lighting, circulation, toilet, furniture, and permanence structures. Additionally, it was observed that the presence of this equipment in the cityscape deserves to be reconsidered, as its implementation was not preceded by the development of intervention, animation, and/or education projects, nor was it based on popular demands
Exploring the biofilm inhibitory potential of Candida sp. UFSJ7A glycolipid on siliconized latex catheters.
No full textBiosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical appli-
cations. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A,
particularly for its application in bioflm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and
characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efciency at low concentra-
tions. Its composition, confrmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography
(TLC), identifed it as an anionic biosurfactant with a signifcant ionic charge of -14.8 mV. This anionic nature contributes
to its bioflm prevention capabilities. The glycolipid showed a high emulsifcation index (E24) for toluene, gasoline, and soy
oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against bioflms
formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter
surfaces were preconditioned with 2 mg/mL of the glycolipid, bioflm formation was reduced by up to 97% for E. coli and
C. albicans and 57% for E. faecalis. These results are particularly signifcant when compared to the efcacy of conventional
surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological
tool in reducing bioflm-associated infections on medical devices, demonstrating their promising applicability in healthcare
settings