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Este trabalho aborda um capítulo não publicado do livro As ideias fundamentais da matemática, do matemático, engenheiro e astrônomo brasileiro Manuel Amoroso Costa. O exame dos rascunhos de próprio punho do livro, contidos no arquivo pessoal do autor, revelou a existência de um capítulo que Amoroso Costa escreveu para o livro, mas que decidiu suprimir, que trata do conceito matemático de grandeza. O conteúdo desse capítulo é discutido neste artigo, que também apresenta transcrições de alguns fragmentos da segunda versão do texto inédito. A análise do capítulo revela forte influência do lógico-matemático Louis Couturat, cujas ideias são aqui expostas, além de sugerir que o processo de abandono do paradigma da matemática como ciência da grandeza, na passagem do século XIX para o XX, pode ter repercutido no processo de elaboração do livro.

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.

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.

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.

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. [ABSTRACT FROM AUTHOR]

ABSTRACT The objective of this study was to evaluate the development of pitaya cuttings in different substrates under different frequencies of irrigation. The experiment was conducted from January to May 2017 in a greenhouse at Universidade Federal Rural da Amazônia, Capitao Poço, Pará, Brazil. A completely randomized 3 × 7 factorial design with four replicates was used. Pitaya plants were grown from cuttings in three types of substrates (S1: potting soil; S2: potting soil + cattle manure + wood shavings; and S3: washed sand) under seven irrigation frequencies (24, 48, 72, 96, 120, 144, and 168 h). There was interaction between treatments for root dry matter production, root length variables, the other variables showed no interaction between treatments. The greater development of new and vigorous tissues of the aerial part, the substrates with composition black earth and black earth + manure + sawdust are indicated, and the adoption of the irrigation frequency of 72 h or 96 h. The use of substrate based on black earth + manure + sawdust, allows savings in the rational use of water and energy with the application of the 96 h irrigation frequencies, maintaining satisfactory levels of development to the plant. The washed sand substrate can be used for propagation when this material is abundant, however, greater attention should be paid to the supply of water and nutrients to the plant.

A grounding system (GS) is an indispensable component in an electrical system network, as it is responsible for conducting electrical discharges to the ground due to faults caused by lightning strikes or transient system failures. Globally, it is estimated that 40 lightning strikes occur per second on the planet, amounting to around 1.2 billion per year, resulting in daily losses of various electrical equipment and human fatalities ranging from 6,000 to 24,000. Additionally, soil resistivity, which impedes the flow of electricity from electrical discharges into the ground, leads to inadequate mitigation of electrical overload effects, resulting in poor GS performance. Consequently, the implementation of ground enhancement materials (GEMs) to reduce impedance to optimal levels becomes necessary. The objective of this review is to broadly examine the current status of GEMs reported in the literature for use in GS, focusing on their composition and their effectiveness in improving soil conductivity and dissipating electrical currents as well as to identify emerging trends and current challenges in the development and application of these materials, in order to provide information to guide future research in the design and implementation of efficient and safe GS. [ABSTRACT FROM AUTHOR]

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.

PURPOSEThe LUME-Lung 1 study has brought consistent evidence of the effective use of nintedanib in lung adenocarcinoma as a second line of treatment; however, differences among ethnicities have been found in some studies.METHODSThis was a retrospective review among 21 medical centers of 150 patients with a confirmed diagnosis of lung adenocarcinoma, included in a compassionate use program of nintedanib from March 2014 to September 2015. The current study aimed to analyze the effectiveness of nintedanib in combination with docetaxel in the Mexican population, using progression-free survival rate and the best objective response to treatment by RECIST 1.1 as a surrogate of effectiveness. In addition, we examined the toxicity profile of our study population as a secondary end point.RESULTSAfter exclusion criteria, only 99 patients met the criteria for enrollment in the current study. From the total study population, 53 patients (53.5%) were male and 46 (46.5%) were female, with an average age of 60 years and stage IV as the most prevalent clinical stage at the beginning of the compassionate use program. A total of 48 patients (48.5%) had partial response; 26 (26.3%), stable disease; 4 (4%), complete response; and 16 (16.2%), progression; and 5 (5%) were nonevaluable. We found a median progression-free survival of 5 months (95% CI, 4.3 to 5.7 months). The most common grade 3 or 4 adverse reactions were fatigue (14%) and diarrhea (13%).CONCLUSIONNintedanib, as part of a chemotherapy regimen, is an effective option with an acceptable toxicity profile for advanced lung adenocarcinoma after first-line treatment progression.

Background A relationship between the EGFR signaling pathway expression in skin and the use of targeted cancer therapies has been previously demonstrated. Consistent evidence to support the use of skin biopsies as a surrogate for therapeutic evaluation is needed. The purpose of this study was to establish the relationship between the expression of EGFR signaling pathway markers in skin samples from EGFR‐mutated metastatic lung adenocarcinoma patients and their response to tyrosine kinase inhibitors. Methods This was a prospective single blind analysis of 35 skin biopsies from 31 patients with confirmed advanced EGFR‐mutated lung adenocarcinoma. Immunohistochemistry was performed: EGFR, p27, Ki67, STAT3 and MAPK, as well as H&E histopathological analysis, in order to determine their treatment response to tyrosine kinase inhibitors. Results EGFR, Ki67, STAT3, stratum corneum thickness (number of layers and millimeters) from skin samples had a statistical correlation with an adequate treatment response (P = 0.025, 0.015, 0.017, 0.041, 0.039 respectively). EGFR, p27 and number of layers of the stratum corneum were related to a better median progression‐free survival (P = 0.025 and P = 0.030). Conclusions The relationship between EGFR pathway inhibition in the skin and oncological outcomes obtained explains the parallel biological effects of tyrosine kinase inhibitors. We hope that our work incites future research to help validate and assess the use of these markers as potential prognostic and predictive factors.

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.

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.

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]

Emergence of bacterial infections, including those associated with Staphylococcus aureus, brings up a need for searching new and more effective strategies for clinical treatment. The use of medicinal plants associated with conventional antibiotics may represent a therapeutic option. Currently, studies evidence the synergistic effect achieved by combining plant extracts with antibiotics. Our objective was evaluate the in vitro antimicrobial activity and bactericidal kinetics of Matricaria recutita extract (chamomile) and its association with cephalexin and norfloxacin on clinical isolates of S. aureus from bovine origin, characterized as resistant. The tests were performed by method of dilution in solid medium to determine the Minimum Inhibitory Concentration (MIC). In both combinations of M. recutita extract with antibiotics norfloxacin and cephalexin, we observed MIC in dilution 1:64, corresponding to 8μg/mL of the antibiotic and 13.43 μg/mL of extract. Cephalexin associated with chamomile extract produced a effect of the combination in 75% of samples in their MIC. The combination of natural products frequently used by the population with the antibiotics tested in this study, could represent a therapeutic option for treatment of infections caused by S. aureus, as well as the prevention of the increasing development of resistance.

Objetivou-se estudar o desempenho agronômico do pimentão cv. Ikeda, irrigado com diferentes qualidades de água, sob dois métodos de manejos de irrigação: reflectometria no domínio da frequência e tensiometria, sob ambiente protegido. O delineamento estatístico utilizado foi o inteiramente casualizado, em esquema de parcelas subdivididas, constituído de três qualidades de água nas parcelas, e dois manejos de irrigação nas subparcelas. Foram avaliadas a produtividade total; produtividade comercial; eficiência do uso da água; massa média dos frutos; comprimento; diâmetro; relação comprimento/diâmetro; teor de sólidos solúveis; acidez titulável e pH. Os resultados obtidos permitem concluir que a produtividade e qualidade físicas dos frutos de pimentão não foram afetadas pela qualidade da água de irrigação, enquanto a menor demanda hídrica quantificada pela tensiometria influenciou significativamente apenas nos pH dos frutos.

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Copyright of Anaquel de Estudios Árabes is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)