Resumo Criticamos a polissemia do significante “matemática”. Seu sentido do senso comum não deveria ser considerado suficiente para embasar a Educação Matemática. Descrevemos uma forma de discurso que emergiu na Grécia Antiga, originário da necessidade social de evitar conflitos intrafamiliares por meio de acordos precisos, leis escritas e diálogo democrático dentro de uma situação histórica singular. Essa forma de discurso emergiu junto com a cunhagem de moedas, tornou-se numericamente precisa com o movimento pitagórico e logicamente precisa com a crise desencadeada pelo paradoxo de Russell no começo do século passado. Mostramos como essa forma de discurso se desenvolveu na história junto com comunidades que vieram a se chamar “ciências exatas”, entre as quais a Matemática, uma comunidade de discurso proeminente. Terminamos o artigo sugerindo uma agenda política para a Educação Matemática.

Abstract We criticize the polysemy of the signifier “mathematics”. Its commonsense meaning should not be considered enough to ground mathematics education. We describe a form of speech emerging in Ancient Greece, originated from the social necessity to avoid intra-family clashes by means of precise agreements, written laws, and democratic dialog in a singular historical situation. This form of speech emerged together with coinage, was made numerically precise with the Pythagorean movement, and logically precise after the crisis unleashed by Russell’s paradox in the beginning of the last century. We show how this form of speech has developed in history together with communities that came to be known as “exact sciences”, among which is Mathematics, a distinguished community of speech. We end the paper suggesting a political agenda for mathematics education.

Near-infrared spectroscopy (NIRS) could be a useful continuous, non-invasive technique for monitoring the effect of partial pressure of carbon dioxide (PaCO2) fluctuations in the cerebral circulation during ventilation. The aim of this study was to examine the efficacy of NIRS to detect acute changes in cerebral blood flow following PaCO2 fluctuations after confirming the autoregulation physiology in piglets. Fourteen piglets (<72 h of life) were studied. Mean arterial blood pressure, oxygen saturation, pH, glycemia, hemoglobin, electrolytes, and temperature were monitored. Eight animals were used to evaluate brain autoregulation, assessing superior cava vein Doppler as a proxy of cerebral blood flow changing mean arterial blood pressure. Another 6 animals were used to assess hypercapnia generated by decreasing ventilatory settings and complementary CO2 through the ventilator circuit and hypocapnia due to increasing ventilatory settings. Cerebral blood flow was determined by jugular vein blood flow by Doppler and continuously monitored with NIRS. A decrease in PaCO2 was observed after hyperventilation (47.6±2.4 to 29.0±4.9 mmHg). An increase in PaCO2 was observed after hypoventilation (48.5±5.5 to 90.4±25.1 mmHg). A decrease in cerebral blood flow after hyperventilation (21.8±10.4 to 15.1±11.0 mL/min) and an increase after hypoventilation (23.4±8.4 to 38.3±10.5 mL/min) were detected by Doppler ultrasound. A significant correlation was found between cerebral oxygenation and Doppler-derived parameters of blood flow and PaCO2. Although cerebral NIRS monitoring is mainly used to detect changes in regional brain oxygenation, modifications in cerebral blood flow following experimental PaCO2 changes were detected in newborn piglets when no other important variables were modified.

Abstract The capability to recycle waste materials, such as steel slag, has appealed to the construction industry, as the cement industry faces a major challenge to reduce carbon dioxide (CO2) emissions into the atmosphere. This paper investigated the obtainment of cement pastes with Kanbara reactor desulfurization waste slag (KR slag) through alkaline activation using silicate and sodium hydroxide solutions. The mixtures were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), compressive strength, and physical property tests. The FTIR, XRD, and TGA results pointed to chemical activation, forming C-S-H and C-(A)-S-H gels. The formation of these compounds indicated the possibility of using KR slag in cementitious composites for civil construction.

Resumen El objetivo de este trabajo es estudiar la viabilidad del empleo de Drones para mapear e inspeccionar manifestaciones patológicas en pavimentos asfálticos en comparación con el método tradicional. Se establecieron parcelas muestrales cada 20 m, con 6 m de extensión, totalizando 20 estaciones, las cuales tuvieron sus manifestaciones patológicas anotadas y calculado el Índice Global de Gravedad para el área de estudio. Los resultados obtenidos con las metodologías de referencia y alternativa se confrontaron en función de las patologías identificadas y el tiempo empleado en los levantamientos. Los resultados demostraron viabilidad para el empleo de Drones en la inspección de patologías de pavimentos asfálticos, tomando como base la Norma DNIT 006/2003 - PRO, obteniendo resultados similares a la metodología tradicional con reducción significativa del tiempo de operación (33,3%).

Abstract This work objective is to study the feasibility of the Drones’ use for mapping and inspecting pathological manifestations in asphalt pavements compared to the traditional method. Sampling plots were established every 20 m, with 6 m extension, making a total of 20 stations, which had their pathological manifestations recorded and calculated with the Global Severity Index for the study area. The results obtained by the reference and alternative methodologies were confronted according to the pathologies identified and the time spent in the surveys. The results showed feasibility in the use of drones for inspection of pathologies in asphalt pavements, based on DNIT 006/2003 - PRO, obtaining results similar to those of the traditional methodology with a significant reduction of the time of operation (33.3%).

Resumo Este trabalho objetiva estudar a viabilidade do emprego de Drones para mapeamento e inspeção de manifestações patológicas em pavimentos asfálticos comparando ao método tradicional. Foram estabelecidas parcelas amostrais a cada 20 m, com 6 m de extensão, totalizando 20 estações, as quais tiveram suas manifestações patológicas anotadas e calculado o Índice Global de Gravidade para a área de estudo. Os resultados obtidos pelas metodologias de referência e alternativa foram confrontados em função das patologias identificadas e do tempo gasto nos levantamentos. Os resultados demonstraram viabilidade para emprego de Drones para inspeção de patologias em pavimentos asfálticos, tomando como base a Norma DNIT 006/2003 - PRO, obtendo resultados similares à metodologia tradicional com redução significativa do tempo de operação (33,3%).

RESUMO Este estudo analisou a intensidade dos jogos Kinect Sports® em universitários através das variáveis hemodinâmicas e da percepção subjetiva de esforço. Tratou-se de um estudo experimental, com 34 jovens estudantes (21.5±1.9anos) que foram submetidos a três sessões consecutivas de jogos, divididas em jogos de boxe, boliche, beisebol e tênis; vôlei de areia, golfe, atletismo e esqui; tênis de mesa, futebol, dardos e futebol americano. A frequência cardíaca (FC), pressão arterial (PA) e percepção subjetiva de esforço (PSE) foram registradas a cada dois minutos de cada jogo. One-way ANOVA for repeated measurements was used to verify differences in HR, BP and PSE at each time of the game and the effect size (p<0.05). Houve diferenças significativas na FC (p<0.01, η2p<0.284) nos jogos de boxe, atletismo e beisebol; na PAS (p<0.01, η2p<0.203) no atletismo e beisebol, bem como na PSE (p<0.01, η2p<0.309) no boxe, atletismo, esqui, vôlei de areia, tênis, futebol americano e tênis de mesa. Quanto a classificação dos jogos por intensidade, através do percentual de proximidade da Frequência Cardíaca Máxima (FCmáx), apenas o jogo de Boxe se apresentou com intensidade forte (70 a 89% da FCmáx), 50% como intensidade moderada (55 a 69% FCmáx), e 42% dos jogos em intensidade leve (35 a 54% da FCmáx). Conclui-se que uma tabela de classificação que identifique a intensidade dos jogos Kinect Sports® em universitários, possibilita selecionar jogos que estejam voltados a condição física do sujeito, tornando a prática dessa atividade uma alternativa para que o indivíduo passe de um estado de repouso para ativo gerando impactos benéficos a sua saúde.

ABSTRACT This study analyzed the intensity of Kinect Sports® games in college students through hemodynamic variables and perceived exertion. An experimental study, with 34 young students (21.5 ± 1.9 years) who underwent three consecutive games sessions, divided into boxing, bowling, baseball, and tennis games; sand, golf, athletics, and ski flights; table tennis, football, darts, and American football. Heart rate (HR), blood pressure (BP), and rate of perceived exertion (RPE) were recorded every two minutes of each game. One-way ANOVA for repeated measurements was used to verify differences in HR, BP, and RPE at each time of the game and the effect size (p <0.05). There were significant differences in HR (p <0.01, η2p <0.284) in boxing, athletics and baseball games; in PAS (p <0.01, η2p <0.203) in athletics and baseball, as well as in RPE (p <0.01, η2p <0.309) in boxing, athletics, skiing, sand volleyball, tennis, football and table tennis. As for the classification of the games by intensity, through the percentage of proximity of the Maximum Heart Rate (HRmax), only the Boxing game presented with strong intensity (70 to 89% of the HRmax), 50% as moderate intensity (55 to 69% FCmax), and 42% of games at light intensity (35 to 54% of FCmax). It is concluded that a classification table that identifies the intensity of Kinect Sports® games in university students allows selecting games that are geared to the subject's physical condition, making the practice of this activity an alternative for the individual to move from rest to an active state generating beneficial impacts to health.

Sesquiterpene lactones are an important class of secondary metabolites frequently isolated from Vernonanthura genus that present a variety of biological properties, including antiproliferative activity. Due to the limitation of pharmacological studies on Vernonanthura nudiflora, the aim of this work was to investigate their antioxidant potential and antiproliferative activity against human tumor cells, as well as to isolate and identify the chemical constituents present in their aerial parts. The phytochemical investigation resulted in the isolation of the sesquiterpene lactones piptocarphins A, B, D, and a new hirsutinolide derivative, 8α-tigloyloxy-10α-hydroxy-hirsutinolide, besides triterpenes, glycosylated steroids, flavonoids, and one chlorogenic acid derivative. Also, other sesquiterpene lactones were identified by ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (UHPLC-HRMS/MS) from dichloromethane fraction. This fraction showed activity against the tumor cells tested, mainly against leukemia, glioma, ovarian and kidney, with growth inhibitory activity (GI50) less than 0.80 µg mL-1. Piptocarphins A and B, in mixture, showed strong activity against all human cancer cell lines tested, with GI50 values ≤ 0.15 µg mL-1. Piptocarphin D was selective for glioma and resistant ovarian cell lines. The new hirsutinolide derivative showed potent activity against breast (GI50= 0.96 µg mL-1) and resistant ovarian (GI50 = 3.60 µg mL-1) cell lines.

Abstract Hydroalcoholic extracts prepared by conventional methods (in stirred vessel at 25 °C and 1 bar) and, hydroalcoholic and supercritical carbon dioxide (scCO2) extracts prepared in fixed bed extractors (60 ºC and 400 bar) were obtained from pitanga leaves (Eugenia uniflora L.) in order to recover phenolic compounds. Hydroalcoholic and ethanolic extracts obtained in fixed bed were further fractionated in four separators by gradual pressure reduction, using scCO2 as an antisolvent. All extracts and fractions were characterized in terms of extraction yield and the presence of total phenolics and flavonoids. Solvents were found to significantly influence the extraction yields and composition. Yields increased as a function of polarity, whereas the hydroalcoholic extractions displayed the highest yields and the highest amounts of extracted phenols and flavonoids.

ABSTRACT Duguetia furfuracea (Annonaceae) is a shrub found in the Brazilian Cerrado that is used in popular medicine as an antirheumatic, for wound healing, treatment of kidney pain and against pediculosis. The aim of this study was to analyze the extraction of leaves of Duguetia furfuracea, using supercritical CO2, ethanol and hexane as solvents. For the supercritical extraction, an experimental planning 23 with triplicates of the central point was used to evaluate the effects of temperature (313-333 K), pressure (15-23 MPa) and volumetric flow rate (3-6 mL min-1) on the extraction yield, total phenolic content and antioxidant activity compared with extracts obtained by Soxhlet extraction. The effects of the variables on the extraction yield were positive and the pressure had greater influence. However, the highest performances, total phenolic content and antioxidant activities were obtained by the Soxhlet method. The mathematical model based on the Brunauer-Emmett-Teller theory of adsorption correlated satisfactorily the experimental values of the supercritical extraction.

OBJECTIVES: To determine the effect of panretinal photocoagulation (PRP) on the peripapillary retinal nerve fiber layer (RNFL) in nonglaucomatous patients with proliferative diabetic retinopathy (PDR). METHODS: This is a prospective, single center, observational study. Thirty-eight eyes of 26 diabetic patients underwent PRP for proliferative diabetic retinopathy. Peripapillary RNFL thickness was measured using scanning laser polarimetry (SLP) with variable corneal compensation (GDx VCC; by Carl Zeiss Meditec, Dublin, CA) and spectral-domain optical coherence tomography (OCT) (Heidelberg Spectralis, Carlsbad, USA) at baseline and 12 months after PRP was performed. RESULTS: Thirty-eight eyes of 26 patients (15 female) with a mean age of 53.7 years (range 26 to 74 years) were recruited. No significant difference was found among all RNFL thickness parameters tested by GDx VCC software (p=0.952, 0.464 and 0.541 for temporal-superior-nasal-inferior-temporal (TSNIT) average, superior average, inferior average, respectively). The nerve fiber indicator (NFI) had a nonsignificant increase (p=0.354). The OCT results showed that the average RNFL thickness (360° measurement) decreased nonsignificantly from 97.2 mm to 96.0 mm at 1 year post-PRP (p=0.469). There was no significant difference when separately analyzing all the peripapillary sectors (nasal superior, temporal superior, temporal, temporal inferior, nasal inferior and nasal thickness). CONCLUSION: Our results suggest that PRP, as performed in our study, does not cause significant changes in peripapillary RNFL in diabetic PDR patients after one year of follow-up.

RESUMO O presente estudo refere-se ao levantamento das espécies de Begoniaceae ocorrentes no Parque Estadual do Ibitipoca (PEIB), Minas Gerais, Brasil. No Parque foram encontradas oito espécies de Begonia (B. altamiroi, B. angularis, B. angulata, B. apparicioi, cucullata, B. fischeri, B. luxurians e B. rufa), as quais são diferenciadas principalmente pelo hábito e por características das folhas (indumento e forma das lâminas). Do total, seis espécies são exclusivas do Brasil e cinco endêmicas da Mata Atlântica. Este estudo baseou-se em bibliografia, consulta aos principais herbários do país e observações de campo. Constam, também, descrições, ilustrações e comentários para cada espécie, assim como uma chave de identificação para todas as espécies.

ABSTRACT A taxonomic survey for Begoniaceae occurring in the Parque Estadual do Ibitipoca (PEIB), Minas Gerais State, Brazil is presented. Eight species of Begonia were found in the Park (B. altamiroi, B. angularis, B. angulata, B. apparicioi, B. cucullata, B. fischeri, B. luxurians and B. rufa), which are distinguished mainly by their general aspect and by the characteristics of leaves, such as, indumentum and blade shape. Of the total of species found, six are restricted to Brazil, whilst five are endemic from the Atlantic Forest. This study was based on a bibliographic review, consult to the main Brazilian herbaria and field observations. Descriptions, illustrations, and comments are also presented for each species. A key to all species is included.