Potential use of treated wastewater from a cattle operation in the fertigation of organic carrots

The use of treated effluents rich in nutrients and organic matter has intensified in agricultural crops, contributing to the demand for water and fertilizers. The goal of this work was to assess the effects of fertigation with treated dairy cattle wastewater, for the cultivation of carrot (Daucus carota) when applied in four different doses, under field conditions, on nutrient accumulation, productivity, and health quality in the carrot (D. carota). Wastewater from treated cattle (WTC) was treated in a pilot treatment unit (PTU). Cultivation was carried out in two beds, and the WTC applied by drippers. Nitrogen (N) was considered the base element for the dose calculation, and a 100% N dose was equivalent to 150 kg ha−1. WTC doses of 0, 100, 200, and 300% N were evaluated. Productivity was evaluated at 70 and 120 days after sowing, in the aerial part (fresh and dry mass and accumulation of nutrients), in the main roots (fresh and dry mass, accumulation of nutrients, diameter, length, and sanitary quality), and as the total productivity of the two organs. As a result, an increase in productivity was observed for all treatments with WTC and accumulation of Ca and Mg. The roots did not present contamination; therefore, the carrots were fit for human consumption. It was concluded that the application of WTC in organic cultivation of carrots is a viable alternative means of plant fertilization, providing higher root productivity than the national average, reaching 72.6 t ha−1 for a dose of 100% N, without compromising on sanitary quality and is suitable for human and animal consumption.A utilização de efluentes tratados, ricos em nutrientes e matéria orgânica, tem se intensificado nas culturas agrícolas, contribuindo para a demanda por água e fertilizantes. O objetivo deste trabalho foi avaliar os efeitos da fertirrigação com água residuária de gado leiteiro tratada para o cultivo da cenoura (Daucus carota), quando aplicada em quatro doses diferentes, em condições de campo, no acúmulo de nutrientes, produtividade e qualidade sanitária. As águas residuárias de bovinocultura (ARB) foram tratadas em uma unidade piloto de tratamento (UPT). O cultivo foi realizado em dois canteiros, sendo a ARB aplicada por gotejadores. O nitrogênio (N) foi considerado o elemento base para o cálculo da dose, e uma dose de 100% de N foi equivalente a 150 kg ha-1. Doses da ARB de 0, 100, 200 e 300% de N foram avaliadas. A produtividade foi aferida aos 70 e 120 dias após a semeadura, na parte aérea (massa fresca e seca e acúmulo de nutrientes), nas raízes principais (massa fresca e seca, acúmulo de nutrientes, diâmetro, comprimento e qualidade sanitária) e nas duas partes (produtividade total). Como resultado, observou-se aumento na produtividade para todos os tratamentos com ARB e acúmulo de N, Ca e Mg. As raízes não apresentaram contaminação, portanto as cenouras eram próprias para consumo humano. Concluiu-se que a aplicação da ARB no cultivo orgânico de cenoura é uma alternativa viável de adubação das plantas. Proporciona produtividade de raízes superior à média nacional, chegando a 72,6 t ha-1 para uma dose de 100% N, sem comprometer a qualidade sanitária do produto, que é adequado para consumo humano e animal

Influência da espessura nas propriedades mecânicas, ângulo de contato, absorção e perda em água de membranas derivadas do látex natural

A membrana de látex tem ganhado destaque em uma gama de aplicações, entretanto, a baixa uniformidade em sua espessura provoca discrepância nas propriedades se configurando como problema para a produção em larga escala, principalmente quando se trata de um produto para área biomédica. Portanto, este artigo pretende determinar a influência da espessura sobre as propriedades de membranas derivadas de látex natural. Para tanto, foram produzidas amostras com espessuras de 0,35 mm, 0,40 mm, 0,50 mm, 0,60 mm e 0,65 mm e foram submetidas aos ensaios de dureza, absorção e perda em água, molhabilidade por ângulo de contato e resistência mecânica à tração. Os resultados mostraram que quanto maior a espessura, menor foi a dureza, a absorção de água, o módulo de Young, a deformação e a molhabilidade, porém, maior foi a resistência à tração e a perda de massa em água. O desvio padrão das propriedades das amostras com espessura entre 0,40 mm e 0,60 mm foi até 550% inferior aos desvios encontrados para 0,35 mm e 0,50 mm, até 930% menor para 0,50 mm e 0,65 mm e para as faixas de espessuras entre 0,35 mm e 0,65 mm a diminuição foi de até 800%. Dessa forma, se conclui que para padronizar a produção de membranas de látex, garantindo boa uniformidade nas suas propriedades, as espessuras devem ser de 0,50 mm com desvio de 0,1 mm.Palavras-chave: Dureza. Absorção.  Molhabilidade.  Resistência mecânica. Curativo.

Engolo and Capoeira. From Ethnic to Diasporic Combat Games in the Southern Atlantic

This article provides a re-examination of the main Afrocentric narrative of capoeira origins, the engolo or ‘Zebra Dance’, in light of historical primary sources and new ethnographic evidence gathered during fieldwork in south-west Angola. By examining engolo’s bodily techniques, its socio-historical context and cultural meanings, the piece emphasises its insertion into a pastoral lifestyle and highlights the relatively narrow ethnic character of the practice in Angola. This analysis and the comparison with capoeira helps us to develop certain hypotheses about the formation, migration, and re-invention of diasporic combat games between southern Angola and coastal Brazil, and more broadly, to increase our understanding of how African cultures spread across the southern Atlantic

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Genetical-demographic data from two amazonian populations composed of descendants of african slaves: Pacoval and Curiau

The Amazon region of Brazil includes communities founded by escaped slaves, some of which still remain relatively isolated. We studied two such Afro-Brazilian communities (Pacoval and Curiau), in the rural area of Alenquer, Pará, and in the metropolitan region of Macapá, Amapá, respectively. Among 12 blood loci, alleles considered as markers of African ancestry, such as HBB*S, HBB*C, TF*D1, HP*2M, ABO*B, RH*D-, and CA2*2 were found at frequencies that are expected for populations with a predominantly African origin. Estimates of interethnic admixture indicated that the degree of the African component in Curiau (74%) is higher than that of Pacoval (44%); an Amerindian contribution was not detected in Curiau. Estimated values of African ancestry fit well with the degree of isolation and mobility of the communities. Pacoval exhibited a high proportion of immigrants among the parents and grandparents of the individuals studied, whereas persons living in Curiau exhibited a low level of mobility, despite its location in the metropolitan area of Macapá city, suggesting a relatively strong barrier against the interethnic admixture in this population. In addition, analysis of genetic data in a sub-sample consisting of individuals whose parents and grandparents were born in the study site, and that probably represents the populations two generations ago, indicated that gene flow from non-black people is not a recent event in both populations

Geopolítica y Energía

Uno de los problemas cruciales, si no el más desafiante que está enfrentando el modelo globalizador perverso (como le llamaba Milton Santos), y que puede marcar los límites a su expansión, es el calentamiento global y la necesidad de transitar hacia una nueva matriz energética, tanto a nivel de países como a nivel global. Parece evidente que los precios del petróleo seguirán en los altos niveles alcanzados. Pero no se aprecia todavía una voluntad real de las naciones no firmantes del Protocolo de Kyoto de hacerlo, y al parecer, las dilaciones seguirán por mucho tiempo. Una sociedad como la norteamericana no está en condiciones de hacerlo, pues todo su modelo de ocupación del territorio ha estado basado en la creciente asfaltización y automovilización del país, además del transporte a largas distancias (Ver: Delgado-Ramos en Polis 20). Según éste, citando a Heinberg, señala que: «En plena discrepancia, algunas estimaciones calculan que, en cambio, el conductor estadounidense consume en promedio su peso en petróleo crudo cada semana. En otras palabras esto significa a nivel mundial, que los automóviles sobrepasan en peso a la población en una relación de 4 a 1 y consumen en combustible una cantidad de energía cercana a esa misma proporción que la gente en alimentos