ABSTRACT This study investigated the effectiveness of using the X-ray technique to assess the viability of papaya seeds. The X-ray images were performed in eight replicates of 25 seeds, placed on transparent acrylic plates on double-sided adhesive tape, previously identified, and then submitted to radiation in X-ray equipment "HP Faxitron". After exposure to X-ray radiation, the seeds were submitted to the germination test in rolls of germitest paper and kept in a germination chamber at 20-30 °C for 30 days. Seedlings were photographed and evaluated as normal seedlings, abnormal and non-germinated seeds. Afterward, the X-ray images and the seedlings from the same seeds were visually compared, and the X-ray images clearly showed seeds with and without internal filling. All abnormal seedlings were full seeds; therefore, X-ray images were not able to separate normal and abnormal. A 100% accuracy was verified by comparing the X-ray images and their respective seedlings, full seeds originated normal or abnormal seedlings, and empty seeds corresponded to non-germinated seeds. Therefore, using X-ray images is a promising technique to identify the viability of papaya seeds. The automated analysis of X-ray images is a simple, fast, and efficient technique to provide information on seed viability and generate parameters related to their germination capacity.

ABSTRACT Agroecological management is considered a model of sustainable agriculture that offers social, environmental and economic benefits. The hypotheses of this study were that agroecological production systems can promote changes in the physical fractions of soil organic matter (SOM) associated with aggregates of different origins, and that the greater diversity of plant species in the production system may favour an increase in the carbon concentration of these aggregates. The aim of this study was to a) determine the mass of the free light fraction (FLF), intra-aggregate light fraction (ILF) and light organic matter fraction (LOM) of biogenic and physiogenic soil aggregates; and b) quantify the organic carbon content of the three light SOM fractions and the residual particulate SOM fraction. Five production systems were evaluated: AgF - Agroforestry system; CSun - Coffee grown in full sun; CSha - Coffee grown in shade; FLE - Flemingia grown in alleys; and NT - No-tillage. The aggregates were separated, identified and classified according to their origin or formation pathway into biogenic (formed by biological processes) or physiogenic aggregates (resulting from chemical and physical actions). From these, the mass and carbon content of the FLF, ILF, LOM and residual particulate fractions were quantified. The greater diversity of plant species found in the AgF system has not yet favoured an increase in the carbon content of the aggregates. The longer set-up time and the management practices of the CSun system has led to an increase in the carbon content of the organic fractions of the aggregates (3.44-1.63 g kg-1 for C-LOM; 1.93-1.13 g kg-1 for C-FLF). The lowest overall mean values for LOM and ILF were found mainly in the aggregates of the NT system (1.22-1.67 and 1.55-2.20 g kg-1, respectively), being associated with the shorter time and greater mobilisation of the arable layer. Biogenic aggregation afforded the highest overall mean values for LOM, and increased the mass of the light fractions (15.5%-27.8% for FLF; 23.4%-8.0% for ILF) and the carbon in the C-LOM, C-FLF and residual particulate fractions (42.3%, 12.9%, and 35.0%, respectively) in the surface layer, suggesting an improvement in soil quality.

ABSTRACT Stress caused by defoliation can compromise the physiological quality of soybean seeds. However, there is evidence that the application of nitrogen (N) can be an alternative to reduce the qualitative losses in seeds caused by defoliating insects. The objective of this study was to evaluate the effectiveness of topdressing N fertilization in improving the physiological quality of soybean seeds from plants subjected to artificial defoliation. The experimental design was a randomized block arranged in a 2×4 factorial scheme with four replicates. The treatments consisted of two levels of defoliation (33 and 66%) and four doses of N (0, 50, 100, and 150 kg ha-1), using urea (45% N), applied two days after defoliation. Artificial defoliation was performed during the R3 stage by removing one (33%) and two leaflets (66%) from each trifoliate leaf under field conditions. At stage R5.1, leaf area was quantified, and after harvesting, germination, emergence, length, total dry mass, electrical conductivity, total protein content, mass of 1000 seeds, and tetrazolium (vigor and viability) tests were carried out. It was concluded that increasing the defoliation from 33 to 66% impaired the physiological quality of soybean seeds. The use of nitrogen fertilization for coverage after defoliation at the beginning of the reproductive phase cannot minimize qualitative losses in seeds.

ABSTRACT In the Cerrado, the palm swamps ( veredas ) are characterized by being humid and stable environments that lead to the formation of Histosols ( Organossolos ). and soils with surface horizons of organic constitution, which are fragile and sensitive to anthropic action. This study aimed to evaluate the impact of anthropization (recurrent forest fires and livestock farming) on the chemical, physical and morphological properties of soils in two palm swamps in the Environmental Preservation Area (EPA) of Pandeiros River, Minas Gerais, namely: Água Doce, in preserved condition, and Taboa, in anthropized condition. Four soil profiles were morphologically described, two profiles in each palm swamp, with subsequent chemical and physical analyses, calculations of organic carbon stock and identification of the origin of organic matter. The results were analyzed using descriptive statistics and Pearson’s correlation coefficient. Soil morphological properties were influenced by vegetation cover, drainage and anthropization conditions. As for the physical and chemical properties, adequate values were observed in the preserved palm swamp, including lower bulk density values and higher cation contents. Anthropic actions in the anthropized palm swamp caused degradation of soils, revealed by subsidence, reduction in organic carbon content, increase in bulk density and decrease in fertility. Changes promoted in the soils of the palm swamps compromise ecosystem services, indicating that actions at either local or governmental level should be stimulated for the preservation and conservation of these environments.

ABSTRACT. The screening of cover crops is essential for improving the physical-hydric properties of compacted soils. This study aimed to evaluate the effects of mixed or single cover crops on improving the physical-hydric properties of compacted Oxisol. Species with tap-rooted and fibrous-rooted rooting patterns were evaluated. The species included pearl millet (Pennisetum americanum), pigeon pea (Cajanus cajan), sunn hemp (Crotalaria spectabilis), velvet bean (Mucuna pruriens), white oat (Avena sativa), black oat (Avena strigosa), rye (Secale cereale), black oat + forage turnip (Raphanus sativus), black oat + white lupin (Lupinus albus L.), and black oat + group pea (Pisum arvense L.). Mixing cover crops did not improve the physical properties of the soil. The tap-rooted pigeon pea effectively reduces bulk density and increases porosity and saturated hydraulic conductivity (Ksat) in compact soils. The selection of cover crops with characteristics that improve soil physical-hydric properties is crucial for compacted areas.

ABSTRACT Sandy texture soils have a great expression in agricultural areas worldwide. In the Baixada Fluminense, soils with a sandy texture on the surface horizons are striking, and a good part of these areas is destined for producing vegetables using conventional cultivation methods. The sandy texture is one of the great challenges for agriculture due to the low water retention capacity provided to the soil, the rapid decomposition of organic matter, and the intense loss of nutrients by leaching. In these areas, the action of erosive processes is sometimes observed, whether water or wind erosion. The practices carried out in conventional agriculture can accentuate these processes. This study aimed to evaluate the influence of different soil management systems, with different vegetation covers, on the pathways of aggregate formation, the nutrient contents contained therein, and the organic matter fractions, with the objective of using these properties as indicators of soil quality. The study was carried out in an organic production unit, with no-till system (NT) and conventional system (CT), three vegetal covers were evaluated, namely; seed cocktail 1 (C1) (Crotalaria (Crotalaria juncea) (20 kg ha-1), Jack Bean (Canavalia ensiformis) (150 kg ha-1) and millet (Pennisetum glaucum) (60 kg ha-1)), and seed cocktail 2 (C2) (with 50 % of the amount of seeds used in C1), and spontaneous plants (S. P). Undisturbed samples were collected at the layers of 0.00-0.05 and 0.05-0.10 m, and, from these samples, aggregates with a diameter between 9.7 and 8.0 mm were classified according to the formation route (Biogenic or Physicogenic). From these, the chemical properties were quantified (pH, Ca2+, Mg2+, Al3+, P, Na+, K+), and also the carbon fractions (total organic carbon – TOC, mineral-associated organic carbon – MAOC), particulate organic carbon – POC, and free light fraction carbon – LFC). Based on the results, it was verified that the percentage of biogenic aggregates was higher than the physicogenic one in the layer of 0.00-0.05 m, not being verified influences of the vegetal coverage or the management system. Chemical properties did not differ significantly between training pathways. The CT, for the most part, was the system in which the highest values of chemical properties were observed, and in general, the C2 and S.P coatings were the ones that provided the greatest improvements for chemical properties and carbon content.

Abstract This paper reinterpreted environmental licensing as one of the main instruments of the National Environmental Policy (Law 6,938/1981), in the light of contemporary constitutionalism. Hence, it aimed at harmonizing socioeconomic development and the protection of the dignity of human life with the use of environmental goods. From a literature review, the need to adapt the public administration to the context of enforcing fundamental rights was evidenced, due to the normative force of the Brazilian Constitution, by the development and/ or improvement of the legal instruments made available to the Constitution in order to fulfill its goals. The design of Brazilian environmental licensing allows public decision- making to be based on scientific evidence and enables dialogical participation among all actors involved and/or affected by the licensing object. This potential for complementarity between technical practice and democratic dialogue, adding to the structuring character of complex socioeconomic arrangements, elevates this licensing to a paradigmatic position regarding the institutional design of the instrument. However, in Brazilian practice there are procedural flaws in its use, which need to be better studied, so that licensing be in line with its constitutional requirements.

Resumen Se trata de una relectura del licenciamiento ambiental, como uno de los principales instrumentos de la Política Nacional del Medio Ambiente (Ley n. 6.938/1981), a la luz del constitucionalismo contemporáneo, considerando el objetivo de armonizar el uso de los bienes ambientales con el desarrollo socioeconómico y la protección de la dignidad de la vida humana. A partir de la revisión bibliográfica, se extraen inferencias que permiten sostener que el tratamiento dogmático y práctico del licenciamiento exige que la Administración Pública se adapte al contexto de realización de los derechos fundamentales, debido a la fuerza normativa de la Constitución, con el desarrollo y/o perfeccionamiento de los instrumentos jurídicos puestos a su disposición para el cumplimiento de su finalidad. El diseño del licenciamiento ambiental brasileño permite que la decisión pública se base en evidencias científicas y posibilita el diálogo entre todos los actores involucrados y/o afectados por el proceso de licenciamiento. Tal potencial de complementariedad entre la pericia técnica y el diálogo democrático, sumado a la naturaleza estructurante de los complejos arreglos socioeconómicos, eleva ese licenciamiento a una posición paradigmática en términos del diseño institucional del instrumento. Sin embargo, existen fallas de procedimiento en su utilización en la práctica brasileña, que deben ser mejor estudiadas para que el licenciamiento pueda cumplir su finalidad constitucional.

Resumo Trata-se de uma releitura do licenciamento ambiental, como um dos principais instrumentos da Política Nacional do Meio Ambiente (Lei n. 6.938/1981), à luz do constitucionalismo contemporâneo, considerando o objetivo de harmonização na utilização dos bens ambientais com o desenvolvimento socioeconômico e a proteção à dignidade da vida humana. A partir da revisão da literatura, realizam-se inferências que permitem defender aplicar- se ao tratamento dogmático e prático do licenciamento a necessidade de adaptação da Administração Pública ao contexto de efetivação de direitos fundamentais, em razão da força normativa da Constituição, com o desenvolvimento e/ou aprimoramento dos instrumentos legais colocados a sua disposição para o cumprimento de seu desiderato. O desenho do licenciamento ambiental brasileiro permite que a tomada de decisão pública seja baseada em evidência científica e possibilita a participação dialógica entre todos os atores envolvidos e/ ou atingidos pelo objeto do licenciamento. Tal potencial de complementaridade entre fazer técnico e diálogo democrático, somando- se ao caráter estruturante de arranjos socioeconômicos complexos, alça esse licenciamento a uma posição paradigmática quanto ao desenho institucional do instrumento. Não obstante, há falhas procedurais em sua utilização na praxe brasileira, que precisam ser mais bem estudadas, de modo a que o licenciamento possa coadunar-se a seu desiderato constitucional.

Abstract In this study we investigate the niche interaction between the frogs Physalameus cuvieri and Physalaemus kroyeri that occur in syntopy in water bodies of the Atlantic Forest located in the eastern Bahia State, Brazil. We investigated the niche width and overlap in the calling activity time, microhabitat use, diet composition, advertisement call, and body size. Both species preferred the same substrate and calling substrate categories, and showed low niche width values and high spatial niche overlap values. The pseudocommunity analysis revealed the absence of competition in space use. Ants and termites were the most important items in the diet of both species with the pseudocommunity analysis indicating an absence of competition in the diet. The two species demonstrate a greater similarity in body proportions and a high overlap in the calling activity time. However, they showed divergence in acoustic parameters, especially in the dominant frequency and call duration. Our results reinforce the role of advertisement call as a relevant attribute for anuran coexistence and highlight the importance of analyzing the various axes of the multidimensional niche for the most reliable description of the existence and magnitude of niche partitioning. State Brazil time use composition size categories However parameters duration partitioning

Resumen Este artículo se propone abordar el uso de los espacios públicos por parte de los movimientos organizados que llevaron a miles de personas a las calles entre marzo de 2015 y marzo de 2016 y que culminaron con la destitución de la presidenta Dilma Rousseff. Parte de la premisa de que aunque la organización de estas manifestaciones se produjo a través de las redes sociales, fue en la apropiación del espacio público por parte de los respectivos grupos donde se materializaron. De forma más tímida, debido a la pandemia de COVID 19, los manifestantes volvieron a las calles en 2020. Para la investigación, utilizamos el aporte teórico sobre la estructuración del espacio urbano y su dimensión simbólica, seguido de la recopilación de información sobre las manifestaciones a través de los principales periódicos en circulación. El balance es que la localización de las manifestaciones siguió la lógica simbólica de la estructuración del espacio urbano, donde el grupo contra el impeachment tuvo su espacio de manifestación asociado al centro principal de las ciudades y los grupos que exigían la destitución de la presidenta ocuparon los espacios identificados con la reproducción del capital financiero y/o la vivienda de las élites. Esta lógica se mantuvo durante las manifestaciones que tuvieron lugar en 2020.

Résumé Cet article propose d'aborder l'utilisation des espaces publics par des mouvements organisés qui ont conduit des milliers de personnes dans la rue entre mars 2015 et mars 2016, situations qui ont abouti à la destitution de la présidente Dilma Rousseff. Elle part du postulat que, si l'organisation de ces manifestations s'est faite à travers les réseaux sociaux, c'est dans l'appropriation de l'espace public par les groupes respectifs qu'elles ont eu lieu. De manière plus timide, en raison de la pandémie de COVID-19, les manifestants sont revenus dans la rue en 2020. Pour la recherche, on a utilisé l'apport théorique sur la structuration de l'espace urbain et sa dimension symbolique, suivi de la compilation d'informations sur les manifestations à travers les principaux journaux en circulation. Le bilan fait est que le lieu des manifestations suivait la logique symbolique de la structuration de l'espace urbain, puisque le groupe opposé à la destitution avait son espace de manifestation associé au centre principal des villes et aux groupes qui réclamaient la destitution du Président a occupé les espaces identifiés à la reproduction du capital financier et/ou du logement élitiste - logique maintenue lors des manifestations qui ont eu lieu en 2020.

Abstract This article addresses the use of public spaces by organized movements that led thousands of people to the streets between March 2015 and March 2016 and culminated in the President Dilma Rousseff impeachment. It starts from the premise that although the organization of these manifestations occurred through social networks, it was in the appropriation of public space by respective groups that they took place. In a timider way, due to the COVID 19 pandemic, the protesters returned to the streets in 2020. For the research, we used the theoretical contribution of urban space structuration and its symbolic dimension, followed by the compilation of information regarding protests published at major newspapers in circulation. The balance shows that the location of social manifestations followed the symbolic logic of urban space structuration, where the group opposed to the impeachment had its space of demonstration associated with the main center of cities and the groups that demanded the withdrawal of President Roussef occupied the spaces identified with the reproduction of financial capital and/or elite housing. This logic was maintained during the demonstrations that took place in 2020.

Resumo Este artigo se propõe a abordar o uso dos espaços públicos pelos movimentos organizados que conduziram milhares de pessoas às ruas entre março de 2015 e março de 2016, situações que culminaram no impeachment da Presidenta Dilma Rousseff. Parte da premissa de que, embora a organização dessas manifestações tenha ocorrido por meio das redes sociais, foi na apropriação do espaço público pelos respectivos grupos que elas se concretizaram. De uma forma mais tímida, por conta da pandemia de COVID-19, os manifestantes voltaram às ruas no ano de 2020. Para a pesquisa, utilizou-se do aporte teórico acerca da estruturação do espaço urbano e de sua dimensão simbólica, seguida da compilação das informações referentes às manifestações por meio dos grandes jornais em circulação. O balanço que se faz é que o local das manifestações seguiu a lógica simbólica da estruturação do espaço urbano, pois o grupo contrário ao impeachment teve seu espaço de manifestação associado ao centro principal das cidades e os grupos que exigiam a retirada da Presidenta se ocuparam dos espaços identificados com a reprodução do capital financeiro e/ou moradia das elites - lógica mantida durante as manifestações ocorridas no ano de 2020.

In this work, the combined use of p-sulfonic acid-calix[n]arene and microwave energy to hydrolyze the 1,3-dioxolane ketal of isatin was evaluated with excellent results. This is the first time that p-sulfonic acid-calix[n]arene has been used as the catalyst in a ketal hydrolysis reaction and the deprotection of the ketone carbonyl of isatin is reported. The presence of 2.5 mol% of p-sulfonic acid-calix[4,6]arene at 160 ºC resulted in over 96% conversion of this ketal in 10 min, with the additional advantage of using water as a solvent. This catalytic system (aqueous phase containing p-sulfonic acid-calix[4]arene) was reused for five consecutive cycles, with a conversion above 96% maintained. This reusable system is not practicable using p-toluenesulfonic acid and p-hydroxybenzenesulfonic acid as catalysts since both are extracted to the organic phase with the reaction product. The hydrolysis of 1,3-dioxolane ketal of isatins with different substituents (CH3, I, Br, Cl, F, NO2) in the aromatic ring was also evaluated. The protecting group of 5-methyl-isatin was removed with 73% conversion using 2.5 mol% of p-sulfonic acid-calix[4]arene at 160 ºC for 5 min. In contrast, the ketal of 5-nitro-isatin reached 80% conversion using the same conditions after 40 min.

Resumen: Este estudio tuvo como objetivo evaluar la ingesta, digestibilidad aparente, balance hídrico, balance de nitrógeno y rendimiento productivo en corderos alimentados con ensilaje de nopal asociado con forrajes tropicales. En el experimento se utilizaron 40 corderos machos cruzados intactos, con un peso corporal inicial de 18.85 ± 1.2 kg. El diseño experimental fue completamente al azar, con 5 tratamientos y 8 repeticiones. Los tratamientos consistieron en dietas con diferentes proporciones de pasto buffel y salvado de trigo como fuentes de fibra detergente neutro (FDN), en ensilaje de alimento total (EAT) a base de nopal: EAT1 - 279 g/kg de pasto buffel; EAT2 - 240 g/kg de pasto buffel y 17 g/kg de salvado de trigo; EAT3 - 198 g/kg de pasto buffel y 34 g/kg de salvado de trigo; EAT4 - 108 g/kg de pasto buffel y 74 g/kg de salvado de trigo; EAT5 - 118 g/kg de salvado de trigo. La ingesta más baja de FDN se encontró en corderos que consumieron EAT5 (402 g/día). La digestibilidad aparente de los carbohidratos no fibrosos fue mayor para EAT5, mientras que la digestibilidad aparente de FDN de EAT5 y EAT4 fue mayor que la de EAT1. Las dietas promovieron una ganancia diaria de peso promedio de 180.8 g/día. En condiciones experimentales, el uso de nopal forrajero y concentrado en forma de raciones mixtas totales de ensilaje conduce a una mayor ingesta de proteína cruda, carbohidratos no fibrosos, extracto etéreo y mayor digestibilidad de carbohidratos no fibrosos y fibra detergente neutro, sin embargo, todas las dietas fueron viables en la alimentación de ovinos confinados, proporcionando ganancias de hasta 198 g/d según la formulación de la dieta.

Abstract This study aimed was to evaluate the intake, apparent digestibility, water balance, nitrogen balance, and productive performance in lamb fed cactus pear silage associated with tropical forages. Forty male intact crossbred lambs, with an initial body weight of 18.85 ± 1.2 kg, were used in the experiment. The experimental design was completely randomized, with 5 treatments and 8 replications. The treatments consisted of diets with different proportions of buffelgrass and wheat bran as sources of neutral detergent fiber (NDF), in total feed silage (TFS) based on cactus pear: TFS1 - 279 g/kg of buffelgrass; TFS2 - 240 g/kg of buffelgrass and 17 g/kg of wheat bran; TFS3 - 198 g/kg of buffelgrass and 34 g/kg of wheat bran; TFS4 - 108 g/kg of buffelgrass and 74 g/kg of wheat bran; TFS5 - 118 g/kg of wheat bran. The lowest NDF intake was found in lambs that consumed TFS5 (402 g/d). The non-fibrous carbohydrates apparent digestibility was higher for TFS5, while the NDF apparent digestibility of TFS5 and TFS4 was higher than TFS1. Diets promoted an average daily weight gain of 180.8 g/d. Under experimental conditions, the use of forage cactus pear and concentrate in the form of total mixed rations silage leads to greater intake of crude protein, non-fibrous carbohydrates, ether extract and greater digestibility of non-fibrous carbohydrates and neutral detergent fiber, however, all diets were viable in the feed of confined sheep, providing gains of up to 198 g/d according with the formulation of the diet.

Resumo: Este artigo investiga a produção acadêmica em periódicos sobre a democracia digital no Brasil. Foi realizada uma busca automatizada no Google Scholar e DOAJ por palavras-chave e, após a filtragem manual, o corpus empírico resultou em 502 artigos. Estes artigos foram avaliados com base em análise de conteúdo, buscando identificar as principais características dos autores, assim como as abordagens teóricas e empíricas. Depois, as referências foram avaliadas através da análise de redes. Os resultados evidenciam a hegemonia dos campos da comunicação e da ciência política, um predomínio de análises sobre a esfera civil não organizada e o uso dos conceitos de participação e deliberação. A maioria dos artigos é empírica, faz uso da técnica de análise de conteúdo e privilegia a avaliação de websites e mídias sociais. Concluímos argumentando pela existência de um campo da democracia digital.

Abstract: This article investigates academic production on e-democracy in Brazilian journals. An automated search was performed on Google Scholar and DOAJ for keywords and, after manual filtering, resulted in an empirical corpus of 502 articles. Content analysis of these articles identified the main characteristics of the authors and the theoretical and empirical approaches to the subject. Network analysis analyzed relationships among references. The results show that these studies are largely conducted within the fields of communication and political science, that they tend to focus on the non-organized civil sphere, and that they often mobilize the concepts of participation and deliberation. Most of the articles are empirical using content analysis to examine websites and social media. We conclude by defending the construction of e-democracy as an academic field in Brazil.

ABSTRACT. Water and salt stress conditions affect germination and seedling emergence. It is known that physiological priming can not only trigger different mechanisms to increase the speed and uniformity of germination, but also influence the antioxidant defence system of the seeds, especially in adverse conditions. In this context, the objective of this work was to evaluate the physiological seed quality and the activity of antioxidant enzymes in seeds of Petroselinum crispum induced to tolerate saline stress through osmo-priming. Seeds were placed in polyethylene glycol solutions with three osmotic potentials (-0.5, -1.0 or -1.5 MPa) for 2, 4 or 6 days. Subsequently, they were placed on substrates moistened with sodium chloride solution (NaCl), in concentrations that generated osmotic potentials of -0.2, -0.4, -0.6, -0.8 or -1.0 MPa, to germinate. The germination percentage, germination speed index, seedling length, fresh weight, dry weight and activity of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were evaluated. Germination and germination speed index decreased linearly with the increase in NaCl concentrations, indicating the species sensitivity. As for length, fresh weight and dry weight of seedlings, this effect was more expressive from the potential of -0.4 MPa. The vigour and activity of SOD, POD, and CAT enzymes were reduced in unprimed seeds, emphasising the effectiveness of the technique. The induction of tolerance to saline stress can be related to the activity of the antioxidant system observed in seeds.