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We investigate the impact of asymmetric fermionic dark matter (DM) on the thermal evolution of neutron stars (NSs), considering a scenario where DM interacts with baryonic matter (BM) through gravity. Employing the two-fluid formalism, our analysis reveals that DM accrued within the NS core exerts an inward gravitational pull on the outer layers composed of BM. This gravitational interaction results in a noticeable increase in baryonic density within the core of the NS. Consequently, it strongly affects the star’s thermal evolution by triggering the early onsets of the direct Urca (DU) processes, causing enhanced neutrino emission and rapid star cooling. Moreover, the photon emission from the star’s surface is modified due to a reduction in radius. We demonstrate the effect of DM gravitational pull on nucleonic and hyperonic DU processes that become kinematically allowed even for NSs of low mass. We then discuss the significance of observing NSs at various distances from the Galactic center. Given that the DM distribution peaks toward the Galactic center, NSs within this central region are expected to harbor higher fractions of DM, potentially leading to distinct cooling behaviors.

ABSTRACT Objective: To compare the glucose metabolism of patients with chronic hepatitis C virus infection treated with direct-acting antivirals (DAAs) in pretreatment and sustained viral response (SVR) periods. Materials and methods: This was an intervention pre-post study of 273 patients with chronic hepatitis C virus infection treated with DAAs from March 2018 to December 2019. Glycidic metabolism was evaluated through homeostasis model assessment (HOMA) – insulin resistance (IR) and HOMA-β indices and assessments of insulinemia and HbA1c levels. These parameters were analyzed with a T test by paired comparison of the means of the variables and Wilcoxon's test paired for the median; in the variables with an abnormal distribution, the Z score was generated for the mean in both the pretreatment and SVR periods. Statistical significance was considered at p ≤ 0.05. Results: Among 273 participants, 125 (45.8%) had prediabetes, and 50 (18.3%) had diabetes. In SVR, there was a significant increase in platelets, albumin, alkaline phosphatase, cholesterol and triglycerides and a significant decrease in aspartate aminotransferase, alanine aminotransferase, gamma GT and bilirubin. The HOMA-IR and HOMA-β indices increased in SVR from 1.95 to 2.29 (p = 0.087) and 71.20 to 82.60 (p = 0.001), respectively. Insulinemia increased from 7.60 μU/mL to 8.90 μU/mL (p = 0.011). HbA1c decreased from 5.6 to 5.4 (p < 0.001). Among patients with prediabetes and those with diabetes, the reduction in HbA1c values was significant (p = 0.006 and p = 0.026, respectively). Conclusion: SVR significantly impacts and leads to improvement in glucose metabolism in patients with chronic liver disease induced by hepatitis C virus.

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The prognosis of patients is very poor, with a median overall survival of ~ 15 months after diagnosis. Cadherin‐3 (also known as P‐cadherin), a cell–cell adhesion molecule encoded by the CDH3 gene, is deregulated in several cancer types, but its relevance in GBM is unknown. In this study, we investigated the functional roles, the associated molecular signatures, and the prognostic value of CDH3/P‐cadherin in this highly malignant brain tumor. CDH3/P‐cadherin mRNA and protein levels were evaluated in human glioma samples. Knockdown and overexpression models of P‐cadherin in GBM were used to evaluate its functional role in vitro and in vivo. CDH3‐associated gene signatures were identified by enrichment analyses and correlations. The impact of CDH3 in the survival of GBM patients was assessed in independent cohorts using both univariable and multivariable models. We found that P‐cadherin protein is expressed in a subset of gliomas, with an increased percentage of positive samples in grade IV tumors. Concordantly, CDH3 mRNA levels in glioma samples from The Cancer Genome Atlas (TCGA) database are increased in high‐grade gliomas. P‐cadherin displays oncogenic functions in multiple knockdown and overexpression GBM cell models by affecting cell viability, cell cycle, cell invasion, migration, and neurosphere formation capacity. Genes that were positively correlated with CDH3 are enriched for oncogenic pathways commonly activated in GBM. In vivo, GBM cells expressing high levels of P‐cadherin generate larger subcutaneous tumors and cause shorter survival of mice in an orthotopic intracranial model. Concomitantly, high CDH3 expression is predictive of shorter overall survival of GBM patients in independent cohorts. Together, our results show that CDH3/P‐cadherin expression is associated with aggressiveness features of GBM and poor patient prognosis, suggesting that it may be a novel therapeutic target for this deadly brain tumor.

For decades, lightweight concrete has been used in various civil engineering applications. Cellular concrete is a type of lighweight concrete that is an emerging composite in materials engineering still. However, due to its low weight, it can be integrated with industrial by-products to develop more advanced composites such as ultra-lightweight cellular concrete (ULCC). ULCC is sustainable and regarded as a potential candidate due to its simplicity of use and other benefits. A systematic review of the potential applications of ULCC in geotechnical construction are presented in this review article. Due to technological breakthroughs and changes in environmental conditions, and their material property is one of the variables that influence the degradation of roadway. Several investigations have been conducted by incorporating different materials into pavement structures to achieve longer-lasting and better pavement infrastructures than those at present. Sustainability benefits, workability, low prices, time, and structural capacity are factors that have been widely focused. This study focuses on the raw materials, production techniques, types, and properties of the ULCCs. The boundary densities of the ULCCs were considered from 400 to 1600 kg/m3. Structures all across the globe have benefited from the usage of cellular concrete in some form or another. However, much work in this field should be focused on, particularly in geotechnical applications. Geotechnical applications need specific attention to develop this kind of concrete with enhanced qualities. In order to address this need, this review paper has extensively focused on raw materials, manufacturing procedures, cellular concrete characteristics, types and uses of ULCC, particularly in geotechnical applications. Furthermore, several limitations and gaps in ULCC application in highway construction are highlighted, and recommendations on further improving its use and performance are provided.

An initiative of Indian Government for Open Defecation Free (ODF) country is initiated under Swachh Bharat Abhiyaan (SBA) (Clean India Mission). An affordable toilet unit can cut down the cost implications of this high budget flagship programme. Conventional materials and techniques may not alter the cost, time and other parameters of the project. Therefore, quest for new and sustainable construction is the need of the hour. Thermal power plants, cement, iron and steel industries continue to be the polluters of environment and cause for climate change. Industrial wastes disposal and depletion of raw materials of cement industry are potential issues of concern for researchers around the globe. A zero-Portland cement using Fly Ash (FA) and Ground Granulated Blast Furnace Slag (GGBFS) can be a one-step sustainable solution for prevailing industrial problems. This article presents a case study on low cost geopolymer modular toilet unit for ODF India. It is the first time in India that the modular toilet unit is cast with Geopolymer Concrete (GPC) incorporating the Industrial wastes which enables easy and quick installation and provide the solution to the issue of waste disposal. It is fitted with mechanical self-cleansing system with regular, unintended, automatic and compulsory flushing with optimised quantity of water immediately after use. The GPC toilet unit has also shown the improved performance and functional properties over the conventional toilet unit in terms of embodied energy, GHG, land area, cost and material saving. This successful sustainable attempt can be scaled up to other concreting practices of construction and infrastructure industry, as a part or whole.

Background: Spelling acquisition requires the assimilation of the regularities of the writing system, but these regularities may differ between the native and a foreign language. English spelling acquisition is a challenge for Spanish-speaking children due to differences in the orthographic systems. The aim of this study was to examine to what extent Spanish-speaking children use sub-lexical and lexical information when spelling in English as a foreign language (EFL), and whether this varies across grades. Methods: To achieve this, we administered a spelling-to-dictation task of monosyllabic words to children 9 to 11 years old. Spelling accuracy, written latencies, and writing durations were analysed as a function of phonology-to-orthography consistency, lexical frequency, word length, and the semantic knowledge that the children have of the words. Results: Results showed differences between grades, with word length only influencing younger children. Lexical frequency, consistency, and semantic knowledge facilitated performance in older children. The cumulative exposure to English may lead to an improvement in spelling due to vocabulary growth and increased sensitivity to new spelling patterns and regularities. Such development occurs despite differences between the orthographies of the native and foreign language and even in the absence of explicit instruction in EFL spelling. Conclusions: Semantic information about words helps spelling retrieval during writing in EFL. Spanish-speaking children develop sensitivity to English orthography and spelling patterns, evident in the older group of children.

A laboratory experiment was developed for the continuous flow preparation of an aminal derived from the condensation of furfural with morpholine. The experiment introduces the students to concepts of green chemistry, heterogeneous catalysis, and continuous flow. A cheap and easy setup allows the heterogeneous catalyst reactor to be built in class. The use of furfural reinforces the importance of green chemistry by using one of the key synthons obtained from biomass.

O futebol e o futsal possuem cenários compostos por inúmeros fatores que podem interferir no rendimento esportivo, sendo um destes as mídias sociais, que podem trazer implicações aos futebolistas que utilizam estas mídias. O objetivo deste estudo é desvelar alterações que podem ser provocadas pelas mídias digitais em futebolistas, apresentando possíveis alterações emocionais desencadeadas nestes atletas. O método adotado foi de caráter quali-quantitativo, de natureza descritiva. A coleta de dados foi realizada por meio da aplicação de um questionário fechado. A amostra contou com 59 atletas universitários de futebol e futsal (24 do sexo feminino e 35 do masculino), com média de idade de 23,43 anos (±4,57). Foi constatado que os atletas utilizam diversos meios digitais, sendo que boa parte destes atletas já vivenciou, de alguma forma, um caso de exposição demasiada nas redes sociais ou caso de cibercrime. Além disso, os atletas afirmaram que esses fatores podem interferir negativamente nas mais diversas relações existentes em suas vidas, bem como no rendimento esportivo, sendo até uma possível causa do abandono do esporte. Também foi levantada a possibilidade de ocorrência de alterações emocionais consideradas como negativas, provenientes de possíveis situações vivenciadas pelos atletas, acarretando interferências nos níveis de diversos aspectos psicológicos, gerando desequilíbrio emocional nos futebolistas. É sugerido que os atletas sejam melhor orientados quanto ao uso dos recursos tecnológicos para evitar, ou pelo menos minimizar, casos de exposição excessiva e surgimento de crimes virtuais, minimizando tais alterações emocionais danosas, interferências negativas no cenário esportivo e na vida pessoal desses atletas.

O ambiente de formação no futebol é bastante complexo, necessitando de reflexões constantes e acompanhando novas realidades que surgem, como a imersão no ambiente das redes sociais virtuais e a utilização de tecnologias, que acrescentam novas perceptivas para debates, como quanto a importância da reclusão esportiva, por exemplo. Este tipo de estratégia muitas vezes é adotado em momentos competitivos, visando principalmente aumentar a concentração. Assim, o objetivo foi entender a visão dos treinadores sobre a importância do contexto de reclusão e as possíveis alterações que as novas tecnologias proporcionaram a esta realidade. Foram entrevistados 10 treinadores de formação, com média de idade foi de 47 anos (±11,5). Como resultados, a maioria dos treinadores consideram bom e importante este ambiente de reclusão. Também é possível perceber que há um impacto das tecnologias neste contexto, sendo que apesar de considerarem aspectos positivos quanto as redes sociais, a maioria acha que o uso de celular pode comprometer a atenção em momentos importantes. Contudo, grande parte não considera correto retirá-los dos jovens. Portanto, foi possível constatar que ainda há uma valorização do ambiente de reclusão pelos treinadores, bem como que há um impacto das novas demandas tecnológicas neste, podendo ser então uma oportunidade educativa e de conscientização dos jovens quanto aos riscos e desvantagens relacionados. As reflexões dos profissionais sobre novas demandas são fundamentais, planejando atitudes eficazes e evitando causar situações negativas que possam piorar a situação e gerar mais estresse.

O presente estudo investigou o estado de humor de atletas de Basquetebol das categorias de base de um Clube, comparando o estado de humor no início e no final da temporada de 2018. Participaram 26 atletas, voluntários, do sexo masculino, federados, com idades entre 13 e 15 anos. Os atletas responderam a Escala de Humor de Brunel - BRUMS. Os resultados demonstraram que os atletas apresentaram um estado de humor positivo, pois tanto no início quanto no final da temporada a subescala Vigor obteve os maiores escores. Em relação as comparações entre o início e o final da temporada, os atletas aumentaram os escores das subescalas Vigor e Tensão, além de diminuírem os escores da subescala Fadiga. Pode-se concluir que durante a temporada de 2018 os atletas foram capazes de manter o estado de humor positivo, com valores de Vigor superiores aos demais fatores, o que é caracterizado como ideal para o rendimento esportivo.

Despite much effort to improve treatments, patients with malignant glioma still present a very poor prognosis that has not changed significantly in the last decades. In this context, it is crucial to better understand glioma pathogenesis to identify new molecular prognostic subgroups and therapeutic targets. WNT6 was recently identified as a new oncogenic molecule in glioblastoma (GBM), with prognostic value in patients, but the mechanisms underlying WNT6 aberrant expression in glioma are still unknown. WNT6 was overexpressed in a subset of gliomas independently of IDH mutations, 1p/19q codeletion status, and WNT6 gene copy number. Interestingly, WNT6 expression is associated with the DNA methylation levels of particular CpG regions at both the WNT6 promoter and the gene body in glioma patient samples. HOXA9, a transcription factor previously associated with poorer clinical outcome in GBM, was identified as a novel transcriptional regulator of WNT6, activating the WNT/β‐catenin pathway in vitro and in vivo. In various cohorts of glioma patients, mRNA levels of WNT6 and HOXA9 were significantly correlated, extending our in vitro and in vivo findings into the clinical setting. Interestingly, this novel molecular link between WNT6 and HOXA9 was not limited to glioma, as they were co‐expressed also in patients with other tumor types. Clinically, WNT6 was a prognostic biomarker of shorter survival in GBM, independently of HOXA9 expression. Concomitant high expression of both WNT6 and HOXA9 identified a subgroup of patients with particularly dismal survival. These findings describe novel WNT6 regulatory mechanisms in GBM, establishing particular DNA methylation patterns and HOXA9 as critical regulators of WNT6 expression in glioma. This HOXA9‐WNT6 molecular link supports WNT signaling in GBM cells and is a powerful prognostic biomarker, highlighting the clinical relevance of this axis in patients. Novel therapies targeting WNT6‐HOXA9 signaling may thus be useful for this deadly disease.

We updated the distribution of Amphisbaena mertensi to northeastern central Brazil based on the finding of a specimen in an urban area in the Cerrado. This species had already been recorded in south-central Brazil, Paraguay, and Argentina. Our new record is 300 km away from the nearest point, Araguari, in the north of the State of Minas Gerais, Brazil. We included a distribution map for the species in South America, and a list of the amphisbaenas species found in Distrito Federal and discuss the conservation of this group.

Oil and gas productions yield a by-product designated as produced water (PW). The high oil content of this effluent prevents its disposal or reuse. This study presents a novel alternative for the removal of oil from produced water using saponified babassu coconut oil (SBCO), as the ionic surfactant part which captures the oil by micellar solubilization, followed by ionic flocculation with Ca2+ ions. A factorial experimental design was applied to optimize the oil removal (RE) process. The experiments investigated the influence of SBCO + CaCl2 concentration, temperature (T), and stirring speed (ω). Extraction Percentages (RE) in the range from 64.901% to 88.444% were achieved. Subsequently, the influence of pH, CaCl2/surfactant ratio and oil removal kinetics in the highest RE% system were evaluated, whereby for pH > 7, (calcium chloride/surfactant) ratio of 1:1, and 15 min of stirring, the RE obtained was 100%. The same maximum removal result was obtained using a microemulsion containing SBCO. Thus, it can be affirmed that the application of ionic flocculation using SBCO is an efficient technique in the treatment of PW.

O estudo da coesão de grupo tem grande importância no contexto esportivo, podendo refletir diretamente na busca por objetivos e no sucesso nas competições. Desta maneira, há a busca por estratégias que possibilitem medir a coesão, como no caso dos questionários, permitindo entender sua relação com o desempenho. O objetivo deste estudo foi avaliar as propriedades psicométricas do Questionário de Ambiente de Grupo em atletas de futebol juniores. As propriedades psicométricas foram testadas pela Análise Fatorial Exploratória por meio da Análise Paralela, a Análise Fatorial Confirmatória, a Teoria de Resposta ao Item e o Índice de Confiabilidade foi avaliado por dois indicadores: Alpha de Cronbach e Ômega de McDonalds. Dentre os resultados, foram encontrados alguns indicativos de que há necessidade de ajustes e adaptações, como dimensionamento da escala, além de fatores relacionados a aquiescência positiva e redação de alguns itens. Portanto, foram encontradas algumas instabilidades nas análises das propriedades psicométricas, direcionando para necessidades de ajustes que possam garantir maior precisão do instrumento.

This article explores the Brazilian Blogosfera Progressista (Progressive Blogosphere, hereafter BP), a leftist political communication initiative aiming to conciliate an institutionalized model of organization with a networked model of action. Despite the disparity of resources existing between them, BP proved able to counter effectively the mainstream media’s political framings, thanks to wise networking strategies, which explored the communicative opportunities offered by social media. The Centro de Estudos de Mídia Alternativa Barão de Itararé – Barão de Itararé Alternative Media Studies Center – is an essential piece in this schema, as it works as a coordinating agency for BP members and trains new participants. Our article intends to discuss this and other characteristics of BP as a group, and the challenges it faces at the present, after the rise of Jair Bolsonaro to Brazil’s presidency.

O objetivo deste estudo foi verificar evidências de validade por estrutura interna e relações com outras variáveis para o Inventário de Dismorfia Muscular (IDM). Participaram 150 praticantes de treinamento resistido, com idade entre 15 e 49 anos. Os instrumentos utilizados foram: IDM, avaliação da imagem corporal, Rosenberg self-esteem scale e medidas antropométricas. Os resultados apontaram que exista evidências de validade para IDM, tanto por estrutura interna, como pela convergência com outras variáveis. Ainda, os resultados demonstraram que diferentemente dos demais transtornos alimentares, em que a distorção de imagem corporal ocorre em um grau mais elevado, na dismorfia muscular a distorção de imagem corporal é acompanhada de sintomas como obsessividade com o corpo, controle alimentar e vergonha do corpo. Com base nos achados pode-se concluir que seja difícil estabelecer se o ganho de massa muscular e a redução de gordura são consequências de uma distorção de imagem.

Geopolymer concretes (geocretes) are considered as eco-friendly materials for various building applications. Geocrete has high early strength, less consumption of natural resources, cost-effectiveness, capacity to form different structural configurations and to remain intact for extended periods without repair works. Meanwhile, geocretes have still exhibited an unstable behavior over time compared to traditional cementitious composites. To overcome this disadvantage, hundreds of studies have focused on the improvement of the microstructure of geocretes with a wide range of improved durability characteristics. Therefore, the review paper has an objective to make available an inclusive review on the production of supplemental-cementing-materials (SCMs), their economic returns, environmental and durability impacts, the conceptual model for geopolymerization, durability affecting factors, and function and long-term durability properties of geocrete. It is concluded that geocrete demonstrated a better resistance against aggressive environment compared to normal concrete, due to its less porous structures. Moreover, it is found that the strength of alkali-activated concrete was found to improve in chloride environment, unlike OPC based concrete. It is also concluded that, the presence of GGBS and MK in alkali-activated materials reduces its alkali-silica reactivity while it is recommended to use high calcium FA in geocrete production for durable concrete and geopolymerization. The higher the molarity of NaOH solution for a given quantity of Na2SiO3 the faster the geopolymerization process and the higher the compressive strength of concrete corrosion current than the OPC concrete. Further long-term durability studies are required to provide test methods and validation techniques since most studies focus on the 28-day curing regime.

Spontaneous fermentation of table olives, as per a traditional Mediterranean process, is still performed empirically; hence, final product quality is somewhat unpredictable. Our main goal was to validate an endogenous (potentially probiotic) lactic acid bacterium strain in Cobrançosa table olives as a vector for a more standardized process, further adding commercial value to the olives themselves. The traditional Portuguese fermentation process typically consists of two stages: sweetening, when olives are periodically washed with spring water to different proportions, and salting, when water is no longer changed, but salt is gradually added to the brine, up to 7–10% (w/w). Lactiplantibacillus pentosus i106 was inoculated as follows: (plan A) 2020/21 harvest, with 0, 3, 5, and 7% (w/v) NaCl, without sweetening; (plan B) 2020/21 harvest, with 5 and 7% (w/v) NaCl, during salting and sweetening; and (plan C) 2019/20 harvest, with 5% (w/v) salt, and sweetening and salting. Microbiological, physical, and biochemical evolutions were monitored for 8 months, and final nutritional and sensory features were duly assessed. Compared to the control, lactic acid bacteria (LAB) predominated over yeasts only if deliberately inoculated; however strain viability was hindered above 5% (w/w) NaCl, and LAB inhibited enterobacteria. Degradation of (bitter) oleuropein to hydroxytyrosol and verbascoside was faster upon inoculation. Color-changing olives from the 2020/21 harvest exhibited higher fat content and lower water content compared to green ones (2019/20 harvest), and different salt levels and inoculation moments produced distinct sensory properties. The best protocol was plan C, in terms of overall eating quality; hence, the addition of Lpb. pentosus i106 provides benefits as a supplementary additive (or adjunct culture), rather than a starter culture.

Objetivo: Analisar de que maneira os usuários do Facebook utilizam a hashtag na organização dos conteúdos relacionados ao corfebol e as questões relacionadas à igualdade de gênero e em quais formatos se dão essas postagens nesta rede social. Metodologia: Buscou-se as hashtags #Korfball #Corfebol #GenderEquality e #MixedGenderSport no Facebook e as mesmas foram analisadas sob a Técnica de Análise de Conteúdo no período de 1 a 15 de agosto de 2019. Resultados e discussão: os resultados geraram duas categorias: hashtags utilizadas na marcação das postagens e conteúdos abordados – igualdade de gênero. Considerações Finais: Pode-se perceber que o Facebook se mostrou um espaço interessante no que tange à difusão de conteúdos relacionados às questões de gênero e as hashtags neste contexto, foram ressignificadas.

Migrant students tend to underperform in Science, Technology, Engineering, and Mathematics (STEM) subjects and are less likely to pursue higher education in STEM when compared with their nonmigrant peers. Given the substantial increase in migration, this disparity has been a central concern in science education in many European countries. The purpose of this study was to investigate the effectiveness of an innovative science outreach program that brings together migrant students and STEM professionals with the same linguistic and cultural backgrounds. The program consists of one-off workshops that follow an inquiry-based approach and include hands-on activities and science communication in the students' heritage language. Using surveys with adapted scales and open-ended questions, we applied a randomized block design with waitlist control groups and repeated measures. Eighty-three Portuguese-speaking migrant students aged 6-17 years participated in the workshops in Germany and the United Kingdom. Results indicate that both the students and STEM professionals evaluated the program positively and that students who participated in the workshops tended to demonstrate an increase in their attainment value for science and an increase in their self-concept of ability for the heritage language 4 weeks after the intervention when compared with students in the control condition. These effects were particularly pronounced for students with low prior motivation to study science or speak the heritage language. Our results thus show that it is possible to foster migrant students' attainment value for science and increase their self-concept of ability regarding the heritage language through a brief science outreach intervention.

Endocrine physiology is a complex subject for students. Game-based learning (GBL) and case-based learning (CBL) are active methodologies that are widely used because of their potential for motivation and greater proximity to the reality of modern students. We evaluated the effectiveness of GBL and CBL among veterinary medicine students compared with a control group using peer tutoring. Students (n = 106) from two institutions volunteered to participate in this study. The participants were submitted to a pretest questionnaire and subsequently were divided into three paired groups by their performance on the pretest exam: (1) traditional class + peer tutoring, (2) traditional class + GBL, and (3) traditional class + CBL. After the students completed the activities, their performance was once again evaluated by applying a new test with the same initial 10 questions and another set of 10 different questions. The students' perceptions and satisfaction with the methodologies and learning strategies were assessed. Anxiety was assessed with the State-Trait Anxiety Inventory before and after the conventional class and after the active methodologies. The GBL group significantly improved their correct answers compared with the baseline (P < 0.05), with no significant difference from CBL and peer tutoring. Anxiety levels did not differ regardless of the time of evaluation or the teaching methodology applied. GBL promoted a greater perception of the stimulus for self-study and problem-solving ability and contributed to the development of group dynamics compared with the group who received CBL (P < 0.05). In conclusion, GBL showed better results than peer tutoring and CBL.

Nanoemulsion systems were investigated in the microflotation of quartz and hematite. Four different depressants were used: Maizena®, soluble starch, amidex, and amylose. The nanoemulsions comprise in a single stable phase varying amounts of water, kerosene, Flotigam EDA® (collector), and n-butyl alcohol, allowing all flotation reagents to be added at the same time, reducing interfacial tension and favoring their application in the process. Microflotation tests were performed in a modified Hallimond Tube and the zeta potential values of the minerals were determined in the presence and absence of reagents. Quartz floatability was not affected by depressants, even when concentrations of 100 ppm of depressant were used in the nanoemulsion. The determined isoelectric point of quartz (pH 2). High levels of hematite depression were obtained for all depressants (80%–90% depression). Quartz floatabilities of up to 95% were achieved by using nanoemulsions in the process. Keywords: Iron oxide depressants, Polysaccharides, Quartz-hematite selectivity, Nanoemulsion

Abstract Conventional treatment of drill cuttings, as drying and thermal desorption, is failing to meet environmental and economic standards; therefore, new alternatives for the treatment of this waste must be developed. The purpose of this study was to remove n-paraffin from drill cuttings using microemulsion systems (MES). The extraction percentage (%) of n-paraffin was quantified by gas chromatography with a flame ionization detector. The optimization of extraction parameters showed that the extraction percentage (%) is directly proportional to the stirring speed and contact time and inversely proportional to the HLB of the surfactant used in the microemulsion system. Results for MES using Alkonat® L90 and Renex® 95 were similar, but Alkonat® L90 was chosen as the best system considering the environmental issue. The MES/cuttings ratio did not influence the percentage of n-paraffin extracted, reaching 55.03% and 56.32% for the ratios of 0.5 and 2.0, respectively. The reuse of MES in multiple extractions showed that MES can be reused in up to two extractions, obtaining up to 86% extraction. The optimal parameters for Alkonat® L90 microemulsion systems were MES/cuttings ratio of 1.0, stirring speed of 132 strokes, and contact time of 80 min, achieving 86.27% extraction. Results obtained in this study may help to better understand n-paraffin removal from drill cuttings by MES, considering the future use of this technology in the design of an industrial treatment plant for both onshore and offshore operations.

Objetivou-se analisar os índices zootécnicos: taxa de natalidade, intervalo de partos, período de serviço e produção de leite, os indicadores de eficiência econômica: margem bruta (MB), margem líquida (ML) e resultado (RE) – (lucro ou prejuízo) além da composição dos custos de produção de 20 propriedades leiteiras na região Norte Fluminense. As propriedades leiteiras obtiveram as seguintes médias para os índices zootécnicos taxa de natalidade de 57,4 ± 2,18% com coeficiente de variação de 21,22%, intervalo de partos de 13,5 ± 0,68 meses com coeficiente de variação de 5,05%, período de serviço de 116,2 ± 9,23 dias com coeficiente de variação de 7,95% e produção de leite de 6,1±2,58 litros por dia com coeficiente de variação de 41,96%. Foi encontrada MB média de R$ 102.731,82 ± R$ 68.087,24 com coeficiente de variação de 66,28% e ML média de R$ 93.531,22 ± R$ 67.948,36 com coeficiente de variação de 72,65%, permitindo aos produtores permanecerem na atividade no curto prazo. E RE (prejuízo) na média de - R$ 360.809,02 ± R$ 89.067,61 com coeficiente de variação de 24,69%. Por apresentar prejuízo, a receita obtida não remunera o investimento realizado. Os baixos índices zootécnicos referentes à taxa de natalidade e produção de leite devem ser melhorados para obtenção de maiores receitas na atividade e melhor produção de leite. A maior porcentagem de participação na composição das receitas e nas despesas de investimento foi o valor imobilizado, quando contabilizado, e a venda do leite e a compra de animais, respectivamente, quando não contabilizado, o valor imobilizado. Com relação às despesas com custeio, as maiores porcentagens foram referentes à mão de obra, a pastagem, a alimentação concentrada e a suplementação volumosa. Os produtores analisados permanecem no curto prazo na atividade, porém para aumentar a produção devem ter melhorados os índices zootécnicos com maior utilização da assistência técnica para obtenção de maior retorno de eficiência econômica.

The present work investigates the microflotation of hematite and quartz using microemulsion and nanoemulsion systems as well as alkyl ether monoamine solutions. This application is based on the ability of such systems to reduce interfacial tension, which favors their application in separation processes. In these systems, the collector was composed by alkyl ether monoamine (Flotigam EDA®), n-butyl alcohol, and kerosene. Corn starch with a high degree of purity was the depressant in the process. Results show that the performance of nanoemulsions is higher than those of the microemulsions and alkyl ether monoamine solutions; by simplifying and leading to an improvement of the process. Keywords: Iron ore, Alkyl ether monoamine, Microflotation, Microemulsion, Nanoemulsion

Nos últimos anos a iniciação esportiva têm sido objeto de estudo de inúmeros trabalhos na literatura internacional, assim como a transição de carreira. Entretanto, grande parte dos trabalhos sobre transição se concentram no término da carreira esportiva. Assim, o objetivo do presente estudo foi analisar a trajetória dos jogadores de futebol no processo da iniciação esportiva até a profissionalização, observando as fontes de estresse e enfrentamento em cada transição de categoria. Um total de 27 jogadores profissionais participaram desse estudo descritivo e exploratório. Um roteiro de entrevista com quinze perguntas baseado nos instrumentos de Gomes (2011) e de Stambulova e colaboradores (2009) foi utilizado para coletar os dados. Numerosas fontes de estresse (por exemplo, comportamento dos pais, lesões, atletas mais fortes) e estratégias de enfrentamento (por exemplo, jogar melhor, conversar com a família) foram identificadas pelos jogadores ao longo do processo de iniciação e profissionalização do esporte. A maioria das estratégias de enfrentamento consistiu em abordagens focadas na resolução de problemas, frente as diferentes demandas de estresse encontradas pelos atletas ao longo de suas carreiras. Como considerações finais, o estudo contribui para que treinadores e líderes da iniciação esportiva possam estar atentos as demandas apresentadas, além das usuais questões físicas, técnicas e táticas. ABSTRACT Stress from sports initiation to the professionalism: an exploratory analysis of the trajectory of professional football athletes In recent years, sports initiation have been the object of study of numerous works inside the international literature, as well as the career transition. However, much of the career transition focuses on the end of the professional career. Thus, the objective of the present study was to analyze the trajectory of football players in the process of sports initiation to professionalization, observing the sources of stress and coping in each category transition. A total of 27 professional players participated in this descriptive and exploratory study. An interview scrip with fifteen questions, based on the instruments of Gomes (2011) and Stambulova and collaborators (2009), was used to gather data. Numerous sources of stress (e.g., parents' behavior, injuries, stronger athletes) and related coping strategies (e.g., problem-focused coping, emotion-focused coping) were identified by the players throughout the process of sports initiation and professionalization. The majority of coping strategies consisted of problem-focused approaches that parallel the different stress demands encountered by the athletes over the course of their career development. As final considerations, the study contributes to the fact that coaches and leaders of sports initiation can be attentive to the demands presented, besides the usual physical, technical and tactical questions.

As mídias sociais, trouxeram modificações no ambiente esportivo, sendo que seus efeitos ainda não são claros. Esta pesquisa possui como objetivo verificar como os atletas veem as relações entre o mundo do esporte e as novas mídias. Participaram deste estudo 211 atletas de 10 equipes, todos participantes de um campeonato de âmbito nacional da categoria sub-20. Os jogadores apresentaram média de idade de 18 anos (± 0,97) e tempo de prática médio de 9 anos (± 3,27). Como instrumento foi utilizado um questionário, desenvolvido especificamente para a finalidade de entender essas relações entre mídias sociais e atletas, composto por 4 perguntas abertas. A análise de conteúdo proposta por Franco (1994) foi utilizada para análise dos dados. Como resultados, grande parte dos atletas enxergam modificações positivas quanto ao surgimento das redes sociais. Os jogadores concordam que a concentração e a atenção podem ser prejudicadas pela utilização de aparelhos celulares, especialmente em momentos importantes da competição. Porém, não é bem vista pelos atletas a retirada dos aparelhos eletrônicos em períodos competitivos, pois os mesmos indicam que isso pode ter efeito negativo. Os aparelhos eletrônicos parecem facilitar a adaptação em diferentes cidades, principalmente em relação aos conhecimentos sobre a cidade. Notamos que diversas mudanças ocorreram no âmbito esportivo promovidas pelas novas mídias sociais, entretanto ainda não há um consenso quanto aos efeitos e possibilidades do uso dessas novas tecnologias. Assim, devemos ter atenção a tais alterações e buscar trabalha-las de modo que isso não prejudique ou tenha efeitos negativo na performance esportiva. ABSTRACT Youth athletes and social media: perceptions and changes in the sports context Social media has brought changes in the sports environment, and its effects are still unclear. This research aims to verify how the athletes see the relationships between the sport world and the new media. This study had as participants 211 athletes from 10 teams, all participants of a national championship of the under-20 category. The players presented mean age of 18 years (± 0.97) and average practice time of 9 years (± 3.27). A questionnaire was used in this research, which was developed specifically for the purpose of understanding these relationships between social media and athletes, composed of 4 open questions. The content analysis proposed by Franco (1994) was used to data analysis. As results, most athletes see positive changes in the emergence of social networks. Players agree that concentration and attention can be hampered by the use of mobile devices, especially at important periods of competition. However, it is not well seen by athletes to withdraw electronic devices during competitive periods, as they indicate that this may have negative effects. The electronic devices seem to facilitate the adaptation in different cities, mainly in relation to the knowledge about the city. We note then that several changes occurred in the sports sphere promoted by social media, however there is still no consensus regarding the effects and possibilities of the use of these technologies. Thus, we must pay attention to such changes and seek to work them in a way that does not hinder or have negative effects on sports performance.