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O objeto deste trabalho são os estudos sobre matemática não-arquimediana feitos pelo matemático, engenheiro e astrônomo brasileiro Manuel Amoroso Costa, que, em 1928, realizou uma série de conferências sobre essa matéria na Faculté des Sciences de Paris. Sem poder contar com os manuscritos dessas conferências, que desapareceram, para esta pesquisa foram considerados outros documentos de trabalho do arquivo pessoal do autor, publicações suas, obras de outros autores e estudos históricos sobre o tema por ele estudado, bem como artigos e notas de jornais da época. Como resultado das análises dessas fontes, este trabalho expõe um panorama dos estudos não-arquimedianos de Amoroso Costa, buscando situá-los em seu próprio tempo, e apresenta questões sobre as quais, possivelmente, ele se debruçou.

We start with two main hypotheses: a) the tendency to overproduction and expanded reproduction is inevitable in a context of production based on competition and the search for profit; b) conflicts for resources and the tendential degradation of the quality of life are also inevitable and are only going to worsen as the expanded reproduction takes its toll on the environment and on the material conditions for the reproduction of capital. This paper explores some underlying phenomena to support these claims, such as the Jevons Paradox, the Tendency of the Rate of Profit to Fall, and the Energy Return on Investment. Finally, it discusses the failure of some of the alternatives to the Growth Paradigm: Sustainable Development, Green Growth, Circular Economy and Degrowth.

This research aimed to analyze the relationship between deforestation (DFT) and climatic variables during the rainy (CHU+) and less-rainy (CHU−) seasons in the Tapajós River basin. Data were sourced from multiple institutions, including the Climatic Research Unit (CRU), Center for Weather Forecasts and Climate Studies (CPTEC), PRODES Program (Monitoring of Brazilian Amazon Deforestation Project), National Water Agency (ANA) and National Centers for Environmental Prediction/National Oceanic and Atmospheric Administration (NCEP/NOAA). The study assessed anomalies (ANOM) in maximum temperature (TMAX), minimum temperature (TMIN) and precipitation (PREC) over three years without the occurrence of the El Niño–Southern Oscillation (ENSO) atmospheric–oceanic phenomenon. It also examined areas with higher DFT density using the Kernel methodology and analyzed the correlation between DFT and climatic variables. Additionally, it assessed trends using the Mann–Kendall technique for both climatic and environmental data. The results revealed significant ANOM in TEMP and PREC. In PREC, the highest values of ANOM were negative in CHU+. Regarding temperature, the most significant values were positive ANOM in the south, southwest and northwestern regions of the basin. Concerning DFT density, data showed that the highest concentration was of medium density, primarily along the highways. The most significant correlations were found between DFT and TEMP during the CHU− season in the Middle and Lower Tapajós sub-basins, regions where the forest still exhibits more preserved characteristics. Furthermore, the study identified a positive trend in TEMP and a negative trend in PREC.

Sweet sorghum (Sorghum bicolor [L.] Moench) is a plant that can be an alternative for the production of bioethanol in semi-arid regions. The objective of this work was to evaluate sweet sorghum 'BRS 506' under salt and water stress. The experimental design was in randomized blocks, in a factorial scheme (4x4), with the first factor referring to the electrical conductivities of the irrigation water (1.5; 3.0; 4.5; and 6.0 dS m-1) and the second refers to irrigation depths (53, 67, 85 and 95% of crop evapotranspiration). Gas exchange, leaf water status, leaf sugars and plant growth were evaluated. Salt and water stress cause negative effects on the growth of sweet sorghum 'BRS 506'. Salt stress causes disturbances in gas exchange and sugar levels. Sweet sorghum 'BRS 506' is tolerant to combined salt and water stress.

Este trabalho traz algumas considerações relacionadas a produção do múltiplo “Ebó contra o carrego colonial”, um objeto de arte afro-brasileira contemporânea e os desafios de sua inserção e comunicação no cenário artístico – e universitário – da produção visual brasileira, uma vez que seu processo de criação evocou diferentes formas de conhecimento que, historicamente, foram exotizados, demonizados e marginalizados na produção de arte no Brasil.

The increase in water demand in regions with limited good-quality water resources makes it necessary to study the effect of low-quality water on plant metabolism. Therefore, the objective of this study was to evaluate the effect of water and salt stress on the levels of mineral elements and accumulation of toxic elements Na+ and Cl− in the leaves and their consequences on the production variables of the sorghum cultivar IPA SF-15. The design adopted was randomized blocks in a factorial scheme (4 × 4), with four salt concentrations (1.5; 3.0; 4.5, and 6.0 dS m−1) and four irrigation depths (51.3; 70.6; 90.0, and 118.4% of crop evapotranspiration ETc) in three repetitions. To obtain nutrient, sodium, and chlorine contents in the leaf, we collected the diagnosis leaf from six plants per plot. For production data, we performed two harvests at 76 and 95 days after planting (silage point and for sucrose extraction). We evaluated the dry mass, fresh mass yield, and total dry mass for the two cutting periods and applied the F-test at the 5% significance level. There was an effect of water stress but not saline, making it possible to use saline water for sorghum irrigation. As for the toxicity of ions, the plant showed tolerance behavior to Na+ and Cl− ions. The grain filling phase was more sensitive than the final phase of the crop cycle.

Agriculture in semiarid regions commonly face problems because of salt and availability of irrigation water. Considering this, studies on cultures resistant to salt and water stresses involving sweet sorghum are required. Therefore, the aim was to evaluate the growth and other mechanisms of tolerance to salinity and water deficit in BRS 506 sweet sorghum. The experimental design was conducted in Upanema-RN, Brazil, in randomized blocks, where the isolated and interactive effect of 3 salinity levels, expressed as the electrical conductivity of irrigation water (1.5, 3.8, and 6.0 dS m−1), and 3 irrigation depths (55, 83, and 110% of crop evapotranspiration) were evaluated. During the cycle, sorghum adapted to the salinity and deficit irrigation depth, since stem height reduced only −5.5% with increasing salinity and −11.95% with decreasing irrigation depth, and aerial dry mass was affected by interaction only at the end of the cycle. Proline, total amino acids, and total soluble sugars were not differenced by stresses. Additionally, around 68.71% of total Na+ was at roots at the end of the cycle. In summary, sorghum BRS 506 was more tolerant to salt than water stress and used Na+ compartmentalization in root cells as the main tolerance mechanism.

This research aimed to analyze the relationship between deforestation (DFT) and climatic variables during the rainy (CHU+) and less-rainy (CHU−) seasons in the Tapajós River basin. Data were sourced from multiple institutions, including the Climatic Research Unit (CRU), Center for Weather Forecasts and Climate Studies (CPTEC), PRODES Program (Monitoring of Brazilian Amazon Deforestation Project), National Water Agency (ANA) and National Centers for Environmental Prediction/National Oceanic and Atmospheric Administration (NCEP/NOAA). The study assessed anomalies (ANOM) in maximum temperature (TMAX), minimum temperature (TMIN) and precipitation (PREC) over three years without the occurrence of the El Niño–Southern Oscillation (ENSO) atmospheric–oceanic phenomenon. It also examined areas with higher DFT density using the Kernel methodology and analyzed the correlation between DFT and climatic variables. Additionally, it assessed trends using the Mann–Kendall technique for both climatic and environmental data. The results revealed significant ANOM in TEMP and PREC. In PREC, the highest values of ANOM were negative in CHU+. Regarding temperature, the most significant values were positive ANOM in the south, southwest and northwestern regions of the basin. Concerning DFT density, data showed that the highest concentration was of medium density, primarily along the highways. The most significant correlations were found between DFT and TEMP during the CHU− season in the Middle and Lower Tapajós sub-basins, regions where the forest still exhibits more preserved characteristics. Furthermore, the study identified a positive trend in TEMP and a negative trend in PREC. [ABSTRACT FROM AUTHOR]

O presente artigo, motivado pela dificuldade dos alunos de Ensino Médio em compreender os conteúdos da Geometria Descritiva, busca responder à seguinte pergunta: um jogo digital para smartphones poderia auxiliar na compreensão do estudo do ponto? Por tratar-se de conteúdo que serve de base para conceitos mais abstratos da Geometria Descritiva, a dificuldade nesse conteúdo pode gerar lacunas que impactarão nas teorias mais complexas seguintes. Este trabalho versa sobre os resultados parciais de uma pesquisa de mestrado, em andamento, que visa analisar como professores do Ensino Médio percebem a relevância de um jogo digital para o estudo do ponto. Desse modo, apresentam-se aqui as teorias norteadoras do projeto de jogo adotando-se os conceitos de ludicidade, aprendizagem baseada em jogos e as aprendizagens significativa e distraída. Os conceitos do estudo do ponto serão sucintamente expostos para que o leitor possa, a seguir, compreender a contextualização e a dinâmica do jogo. Nesse estudo de caso, sete recém-egressos do ensino médio da instituição que sediou a pesquisa foram convidados a avaliar “Frogo, o Jogo do Estudo do Ponto”. Assim, após usufruírem do game, os participantes responderam anonimamente a um formulário eletrônico com perguntas avaliativas abertas e fechadas. Os resultados obtidos nessa consulta inicial indicam que Frogo pode ser um recurso pedagógico digital motivador para os estudantes nativos digitais com potencial para contribuir com um aprendizado divertido e servir de incentivo para o surgimento de projetos como esse que aspirem por um paradigma educacional menos tradicional.

Solid solutions ZnxCd1−xS were compared by coprecipitation and sonochemistry methods, where x=0.2. This rate is the one that presents the best photocatalytic activity and the best performance for the production of hydrogen from a water source, according to our previous results. The influence of the synthesis method on the morphology and its electronic properties of the CdS and Zn0.2Cd0.8S systems was investigated, as well as the effect of the incorporation of Zn in the crystal lattice and its effect on the production of hydrogen from the division of water. X-ray diffraction characterization confirmed the formation of a solid solution corresponding to a face-centered cubic crystalline phase with preferential growth of (111), (220), and (311) planes and hierarchical morphology according to SEM and TEM microscopy, formed by aggregated nanoparticles of ZnxCd1−xS compound. The crystallite size decreased with the Zn incorporation in the crystal lattice from 8.61 nm by a coprecipitation method to 4.37 nm when the synthesis was assisted with sonochemistry, and the crystallite sizes range from 7.92 nm to 3.80 nm for the case of CdS pure. Other characterization techniques were also used, such as photoluminescence (PL), Raman microscopy, and N2 adsorption and desorption. The PL results show tunability of band edge emission as a function of zinc concentration in the Zn0.2Cd0.8S nanoparticles. For the water splitting to hydrogen production, the separation of the charge carriers promoted by the incorporation of Zn in addition to the shallow trap emissions generated defects in the catalyst structure; such processes are important factors found which increased with the sonochemical method, as well as the potential matched positions.

Titanium dioxide (TiO2) is widely used, studied, and synthesized using different methodologies. By a modification of the material, it can be applied to wastewater treatment. A combined sputtering-laser ablation setup was used to deposit TiO2 thin films modified, individually and simultaneously, with gold (Au) and silver (Ag). To investigate the effect of the metal incorporation in titanium and its impact on the photocatalytic activity, with dye discoloration as a pollutant compound model, the deposited films were characterized by UV–Vis, photoluminescence, and Raman spectroscopies, as well as by parallel beam X-ray diffraction. The results showed that films with different Au and Ag loads, and an 18 nm average crystallite size, were obtained. These metals have an essential effect on the deposited film’s compositional, structural, and optical properties, directly reflected in its photocatalytic activity. The photocatalytic test results using UV-Vis showed that, after 1 h of applying a 4.8 V electric voltage, a discoloration of up to 80% of malachite green (MG) was achieved, using ultraviolet (UV) light.

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Agriculture in semiarid regions commonly face problems because of salt and availability of irrigation water. Considering this, studies on cultures resistant to salt and water stresses involving sweet sorghum are required. Therefore, the aim was to evaluate the growth and other mechanisms of tolerance to salinity and water deficit in BRS 506 sweet sorghum. The experimental design was conducted in Upanema-RN, Brazil, in randomized blocks, where the isolated and interactive effect of 3 salinity levels, expressed as the electrical conductivity of irrigation water (1.5, 3.8, and 6.0 dS m−1), and 3 irrigation depths (55, 83, and 110% of crop evapotranspiration) were evaluated. During the cycle, sorghum adapted to the salinity and deficit irrigation depth, since stem height reduced only −5.5% with increasing salinity and −11.95% with decreasing irrigation depth, and aerial dry mass was affected by interaction only at the end of the cycle. Proline, total amino acids, and total soluble sugars were not differenced by stresses. Additionally, around 68.71% of total Na+ was at roots at the end of the cycle. In summary, sorghum BRS 506 was more tolerant to salt than water stress and used Na+ compartmentalization in root cells as the main tolerance mechanism. [ABSTRACT FROM AUTHOR]

Solid solutions ZnxCd1−xS were compared by coprecipitation and sonochemistry methods, where x = 0.2. This rate is the one that presents the best photocatalytic activity and the best performance for the production of hydrogen from a water source, according to our previous results. The influence of the synthesis method on the morphology and its electronic properties of the CdS and Zn0.2Cd0.8S systems was investigated, as well as the effect of the incorporation of Zn in the crystal lattice and its effect on the production of hydrogen from the division of water. X-ray diffraction characterization confirmed the formation of a solid solution corresponding to a face-centered cubic crystalline phase with preferential growth of (111), (220), and (311) planes and hierarchical morphology according to SEM and TEM microscopy, formed by aggregated nanoparticles of ZnxCd1−xS compound. The crystallite size decreased with the Zn incorporation in the crystal lattice from 8.61 nm by a coprecipitation method to 4.37 nm when the synthesis was assisted with sonochemistry, and the crystallite sizes range from 7.92 nm to 3.80 nm for the case of CdS pure. Other characterization techniques were also used, such as photoluminescence (PL), Raman microscopy, and N2 adsorption and desorption. The PL results show tunability of band edge emission as a function of zinc concentration in the Zn0.2Cd0.8S nanoparticles. For the water splitting to hydrogen production, the separation of the charge carriers promoted by the incorporation of Zn in addition to the shallow trap emissions generated defects in the catalyst structure; such processes are important factors found which increased with the sonochemical method, as well as the potential matched positions. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is widely used, studied, and synthesized using different methodologies. By a modification of the material, it can be applied to wastewater treatment. A combined sputtering-laser ablation setup was used to deposit TiO2 thin films modified, individually and simultaneously, with gold (Au) and silver (Ag). To investigate the effect of the metal incorporation in titanium and its impact on the photocatalytic activity, with dye discoloration as a pollutant compound model, the deposited films were characterized by UV–Vis, photoluminescence, and Raman spectroscopies, as well as by parallel beam X-ray diffraction. The results showed that films with different Au and Ag loads, and an 18 nm average crystallite size, were obtained. These metals have an essential effect on the deposited film's compositional, structural, and optical properties, directly reflected in its photocatalytic activity. The photocatalytic test results using UV-Vis showed that, after 1 h of applying a 4.8 V electric voltage, a discoloration of up to 80% of malachite green (MG) was achieved, using ultraviolet (UV) light. [ABSTRACT FROM AUTHOR]

Objective: To determine subclinical cardiovascular disease (sCVD) in middle-aged women with clinically manifested hand osteoarthritis (HOA) and to improve the characterization of cardiovascular risk in this population. Design: We cross-sectionally evaluated the relationship between HOA and sCVD in 1,803 volunteers from the Mexican Teachers' Cohort. From 2012 to 2016, a subsample from Mexico City, the Northern state Nuevo León, and the Southern states Chiapas and Yucatán was invited for clinical evaluations, during which neurologists examined carotid arteries using ultrasound, and a standardized HOA questionnaire was also administered. HOA was defined as age ≥45 years, hand joint pain, and morning stiffness that lasted no longer than 30 minutes. sCVD was assessed using the intima-media thickness (IMT) and atherosclerotic plaques. Results: Among participants with a mean age of 51 years (±4), 18.4% met the criteria for HOA, and the prevalence of carotid atherosclerosis was 23.1%. After multivariable adjustment, women diagnosed with HOA had a 1.8% (95% confidence interval [CI] 0.3, 3.3) greater mean IMT than those without this joint disease. Similarly, women with HOA had 36% (95% CI 1.01, 1.84) higher odds of carotid atherosclerosis. Conclusions: HOA is associated with sCVD in middle-aged women. This relationship might be due to low-grade chronic inflammation; however, further research is required to clarify the underlying mechanisms.