ABSTRACT In this paper we broadly outline the currents of thought on urban planning at the turn of the nineteenth to the twentieth century, its English and French strands in relation to eugenics and the influences of these urban models in two points of the South Atlantic: Brazil and South Africa. This work was possible through a transnational historical analysis of eugenic influences on regional plans in Brasilia and Johannesburg. Considering the specific context of each place, we highlight the importance of the 1950s in the reformulation and applicability of these theories in those corners of the world. Finally, we point out the connections between capital, the national-developmentalist state and the racist/colonial structures that allowed the existence of cities that still cement eugenic dreams and colonized dystopias today.

RESUMO Neste artigo desenhamos de modo amplo as correntes de pensamento sobre planejamento urbano na virada do século XIX para o XX, suas vertentes inglesas e francesas nas relações com o eugenismo e as influências desses modelos urbanos em dois pontos do Atlântico Sul: Brasil e África do Sul. Este trabalho só foi possível pela análise histórica transnacional das influências eugênicas nos planos regionais em Brasília e Joanesburgo. Levando em consideração o contexto específico de cada lugar, destacamos a relevância dos anos 1950 na reformulação e nas aplicabilidades dessas teorias nesses pontos do globo. Indicamos, por fim, as conexões entre capital, estado nacional-desenvolvimentista e as estruturas racistas/coloniais que permitiram a existência de cidades que cimentam, ainda hoje, sonhos eugênicos e distopias colonizadas.

Abstract Constant growth in the concrete floor sector claims new techniques to improve concrete performance and avoid undesirable issues. In this way, materials used in concrete floors are essential, and it is critical to investigate them. Therefore, this study evaluated the influence of surface hardeners on the surface hardness determined by the rebound hammer test of concrete floors prepared with distinct water/cement ratios, curing ages, and cement types. The control parameters of the concrete’s production, including the compressive strength, flexural tensile strength, and bleeding tests were analyzed. In addition, data were assessed by multifactorial analysis of variance (ANOVA). Thus, hardeners increased the surface resistance of the composites, therefore reducing the chances of pathological manifestations occurring. Taken together, we demonstrated that hardeners improved the concrete surface prepared with all mixture proportions, but it was more significant when using the cementitious hardener and higher w/c content (0.6).

abstract This paper compares the development of the cities of Brasília (Brazil) and Johannesburg (South Africa) through the analysis of event and everyday dualisms, as well as life and non-life. Based on a historical methodology and in the light of anthropological theories, we indicate how the constitution of these two apartheid spaces, these events and everyday life, are related through the realization of eugenic utopias that reify people already racialized in colonization. People who still have a dubious function of object and abject. Thus, we point the cement as an actor of the technosphere in the Negrocene, as Malcon Ferdinand suggested and, in the calculation of its transformation into concrete, we see how indispensable people (lives) read by capitalism/colonialism as commodities (non-life), are extracted from the residues of colonial political arrangements. Finally, we conceptualize modern cities as necropolis without forgetting that the alternatives to colonialism, presented by black histories, may indicate different experiences of what body and space are.

resumo Este artigo compara o desenvolvimento das cidades de Brasília (Brasil) e Joanesburgo (África do Sul) pela análise dos dualismos evento e cotidiano; vida e não-vida. A partir de uma metodologia histórica e à luz das teorias antropológicas, indicamos como a constituição desses dois espaços do apartheid, esses eventos e cotidianos, se relacionam pelas concretizações das utopias eugenistas que reificam pessoas já racializadas na colonização. Pessoas que continuam tendo uma função dúbia de objeto e abjeto. Assim, apontamos o cimento como ator da tecnosfera no Negroceno, como sugeriu Malcon Ferdinand e, no cálculo de sua transformação em concreto, vemos como são indispensáveis as pessoas (as vidas) lidas pelo capitalismo/colonialismo como commodities (não-vida), extraídas dos resíduos dos arranjos políticos coloniais. Por fim, conceituamos as cidades modernas como necrópoles sem nos esquecer que as alternativas ao colonialismo, apresentadas pelas histórias negras, podem indicar experiências distintas do que seja o corpo e o espaço.

Two artificial neural networks (ANNs) were developed for producing an austempered ductile iron (ADI) with low-cost chemical composition and mechanical properties as per ASTMA897/897M-16-grade-1050/750/07 standard. Thus, the first ANN predicted the chemical composition range within the lowest cost and required mechanical properties. Next, in the second ANN, the resulting values from the first ANN were refined considering the target chemical composition suggested in the standard. Moreover, mechanical properties and microstructural analyses were undertaken in the ADI produced to support the ANNs’ findings. Hence, ANNs can be used to make a standard-compliant ADI and achieve cost savings.

Abstract Agricultural expansion and fragmentation of native habitats is considered the major cause of declining biodiversity worldwide, negatively impacting the provision and maintenance of nature's contributions to people. Bats are a key group in agricultural landscapes, playing crucial ecological roles in pollination, seed dispersal and control of invertebrate populations. Due to interspecific differences in diet, morphology, physiology and behavior, bats differ in habitat use, with a species-specific response to landscape changes. In this study, we evaluated how bats from different trophic guilds that can be catched with mist nets relate to different habitats present in a hyper-fragmented agricultural landscape. With the use of mist nets, we captured 309 bats in 30 nights between June 2016 and July 2018. Our results show differences in habitat use between species of different trophic guilds. While insectivorous bats have a positive relationship with the amount of water present at the collection point, frugivorous bats show a negative response. These results reinforce the importance of landscape heterogeneity in agricultural mosaics for maintaining biodiversity.

Resumen La expansión agrícola y la consiguiente pérdida y fragmentación de los hábitats nativos se consideran una de las principales causas de la disminución de la biodiversidad en todo el mundo, lo que afecta negativamente la provisión y el mantenimiento de importantes servicios del ecosistema. Los murciélagos representan un grupo clave en los paisajes agrícolas, juegan papeles ecológicos cruciales en la polinización, la dispersión de semillas y el control de las poblaciones de invertebrados. Debido a las diferencias interespecíficas en la dieta, la morfología, la fisiología y el comportamiento, los murciélagos difieren en el uso del hábitat, con respuestas específicas de la especie a los cambios del paisaje. En este estudio evaluamos cómo los murciélagos de diferentes gremios tróficos que pueden ser capturados con redes de niebla, se relacionan con diferentes hábitats presentes en un paisaje agrícola hiperfragmentado. Con la ayuda de redes de niebla, se capturaron 309 murciélagos en 30 noches de recolección entre junio de 2016 y julio de 2018. Nuestros resultados muestran diferencias en el uso del hábitat entre especies de diferentes gremios tróficos. Mientras que los murciélagos insectívoros están positivamente relacionados con la cantidad de agua presente en el punto de recolección, los murciélagos frugívoros muestran una respuesta negativa. Estos resultados refuerzan la importancia de la heterogeneidad del paisaje en los mosaicos agrícolas para mantener la biodiversidad y proporcionar servicios ecosistémicos.

Friction Stir Welding (FSW) is an excellent alternative for joining dissimilar and similar materials in comparison to conventional welding processes. In this sense, this work aims at qualifying FSW to similar AA5083-O and AA5052-O aluminum alloys, with 6.35 mm thickness, in a CNC machining center. Therefore, four welding experiments were undertaken. At first, two types of plate surface finish were considered before joining. Afterward, two tool probe geometries, and changes in the base material position were evaluated. Hence, the welds were mainly analyzed by metallography, tensile testing, and bending tests. Results showed that the machining step to oxides removal and plates alignment is beneficial for the weld processing and the factor that has significant influence to achieve suitable joints is the tool probe geometry. Finally, by obtaining an average ultimate tensile strength (UTS) of around 191 MPa, enhanced microhardness, and bent angle of approximately 150°, the best joint was chosen.

Friction welding is a solid state technology which has been used worldwide. Potential advantages may be recognized as reducing welding project costs, weld weight, environmental impact and to promote enhanced mechanical properties. However, traditional welding methods are still a common practice in many engineering areas. In this sense, this work aims to present the technical advantages for replacing gas metal arc welding (GMAW) by friction welding for joining hydraulic cylinder tubes. The feasibility of friction welding was demonstrated by microstructural analysis, mechanical properties and hydrostatic pressure testing. The results showed enhanced mechanical properties for the friction welded tubes. In addition, macro and microstructural features presented distinguishable process characteristics which reflect in different microhardness values. The friction weld exhibited a better behavior in bending as well as hydrostatic tests.

Resumo A utilização de materiais nobres é requisito básico em aplicações onde existe um ambiente agressivo como na indústria do petróleo e nuclear. Neste panorama, a liga Inconel 625 é frequentemente utilizada como material de cladeamento no revestimento interno de dutos rígidos. Assim, as superligas de níquel exercem papel fundamental nos campos de exploração de águas profundas e, por isso, o conhecimento de métodos modernos de soldagem aplicados a estas ligas e suas consequências nos estados de tensões residuais é importante. Portanto, o presente trabalho faz uma avaliação das tensões residuais após a Soldagem por Fricção e Mistura Mecânica (SFMM) em chapas soldadas de Inconel 625. A união das chapas foi realizada com rotação da ferramenta 200 e 1200 rpm e velocidade de soldagem constante (1mm/s). As medições de tensões residuais na superfície das juntas soldadas foram investigadas através da técnica de difração de raios-X. Além disso, foram avaliadas as macroestruturas e o aporte térmico de acordo com os parâmetros de soldagem empregados. Embora não existam muitos trabalhos relacionados ao processo SFMM para ligas de Inconel, provavelmente devido à sua dificuldade de soldagem, tem sido percebido um aumento na aplicação da soldagem no estado sólido como excelente alternativa para as superligas à base de níquel. Os resultados mostraram que diferentes parâmetros de processo produziram juntas soldadas distintas e, consequentemente, variações na distribuição de tensões residuais. Por fim, um aumento na velocidade de rotação da ferramenta ocasionou um aumento nas tensões residuais na zona de mistura.

Abstract The use of noble materials is a basic requirement in applications where an aggressive environment such as offshore industry and nuclear energy. In this scenario, the Inconel 625 is often used as clad material in rigid pipes. Thus, nickel superalloys play a fundamental role in the deepwater exploration fields and, therefore, understanding of modern welding methods applied to these alloys and their consequences in the residual stress states is very important. Hence, this work evaluates the residual stress distributions after Friction Stir Welding (FSW) applied on Inconel 625 sheets. FSW was performed with tool rotational speed in the range of 200 to 1200 rpm and welding speed constant. Measurements of superficial residual stresses were investigated by X-ray Diffraction. In addition, macrostructures and heat input were evaluated. Although there are only few reports related to FSW applied on Inconel alloys, probably due to this welding process difficulty, it has been regarded that there is cumulative application of a solid state welding as an excellent alternative for nickel superalloys. The results showed that different welding parameters produced distinctly welded joints and consequently changes in the residual stress distributions. Finally, an increase in the tool rotation speed increased the residual stress in the stir zone.

Typically, for automotive shafts, shape distortion manifests itself in most cases after the induction hardening by an effect known as bending. The distortion results in a boost of costs, especially due to machining parts in the hardened state to fabricate its final tolerances. In the present study, residual stress measurements were carried out on automotive drive shafts made of DIN 38B3 steel. The samples were selected in consequence of their different distortion properties by an industrial manufacturing line. One tested shaft was straightened, because of the considerable dimensional variation and the other one not. Firstly, the residual stress measurements were carried out by using a portable difractometer, in order to avoid cutting the shafts and evaluate the original state of the stresses, and afterwards a more detailed analysis was realized by a conventional stationary diffractometer. The obtained results presented an overview of the surface residual stress profiles after induction hardening and displayed the influence of the straightening process on the redistribution of residual stresses. They also indicated that the effects of the straightening in the residual stresses cannot be neglected.

O desempenho produtivo e a possível interferência do flúor sobre a saúde dos animais foram investigados em bovinos Nelore suplementados, por 866 dias, com distintas fontes alternativas de fósforo com diferentes relações fósforo:fluor (P:F). Os tratamentos experimentais foram: Controle negativo (CONTNEG, sem qualquer suplementação com P), fosfato bicálcico (FB 120:1, FB 30:1 e FB 10:1), fosfato monobicálcico (FMBC 60:1), superfosfato triplo (SFT 30:1) e fosfato de rocha de Cajati (FR 10:1). Foram utilizados 49 novilhos, desmamados aos oito meses de idade, castrados e com 230 kg de peso médio, distribuídos em sete piquetes com água e mistura mineral formulada sem P. A dieta padrão foi feita com bagaço de cana (0,03% de P) como volumoso e um concentrado contendo 0,239 % de P oferecido na base de 1% do peso dos animais para permitir um ganho de peso aproximado de 0,50 kg/dia. Até o dia 134, não houve diferença estatística entre os diversos lotes, inclusive para o tratamento CONTNEG, que não recebeu fósforo suplementar na dieta e ganhou 71,6 kg de peso ou 0,633 kg/dia. Após 866 dias de confinamento (2,37 anos), os animais suplementados com o fosfato bicálcico padrão (120:1) ganharam menos peso que os suplementados com as fontes FMCB 60:1, FB 30:1 e SFT 30:1. Até um ano de suplementação fosfórica com fosfato bicálcico padrão (120:1) artificialmente fluoretado com NaF ou com o fosfato de rocha não se detectou danos à saúde ou ao ganho de peso dos animais. As análises de fósforo nos ossos mostraram diferença estatística apenas entre o tratamento CONTNEG e os que tinham fosfato bicálcico. As concentrações de flúor nos ossos se mostraram intimamente associadas à quantidade de flúor disponível nas fontes utilizadas. Conforme a proporção P:F na dieta foi diminuindo, características relacionadas à fluorose dentária ficaram mais evidentes, sendo que os animais que receberam fontes com relação 10:1, apresentaram, ao final do experimento, dentes incisivos permanentes mal formados, quebradiços e com manchas esbranquiçadas.

Weight gain and possible interference of fluoride on animal health was investigated in Nellore cattle supplemented during 866 days with alternative sources of phosphorus with different phosphorus:fluor (P:F) ratios. The five treatments were: (1) Negative control (NC, without any supplemental P), (2) dicalcium phosphate (DCP 120:1, DCP 30:1 and DCP 10:1), (3) monodicalcium phosphate (MDCP 60:1), (4) triple superphosphate (TSF 30:1), and (5) cajati rock phosphate (RP 10:1). We used 49 oxen weaned with 8 months of age and an average weight of 230 kg, distributed into seven paddocks with water and mineral mixture formulated without P. A standard diet consisting of sugar cane bagasse (0.03% P) as roughage and a concentrate containing 0.239% P was provided on 1% of live weight to allow a weight gain of about 0.50 kg/day. Until day 134, there was no statistical difference between the various groups, including the treatment NC which received no supplemental phosphorus in the diet and gained weight of 71.6 kg or 0.633 kg/day. After 866 days of confinement (2.37 years), the oxen supplemented with dicalcium phosphate standard (120:1) gained less weight than those supplemented with sources MDCP 60:1, DCP 30:1 and TSF 30:1. Up to one year of supplementation with dicalcium phosphate artificially fluoridated with NaF or with rock phosphate did not result in damage to health or in weight gain of the animals. Analyses of phosphorus in bones showed statistical difference between treatments, and group NC that did not receive any supplemental P showed the lowest values. The concentration of fluoride in bones proved to be closely related to the amount of fluoride available in the sources used. As the ratio P:F in the diet decreased, characteristic signs related to dental fluorosis became more evident, and the animals that received P supplies with 10:1 ratio showed at the end of the experiment permanent malformed incisor teeth, brittle and whitish stained.

Objetivou-se, com este trabalho, avaliar os efeitos da adição de diferentes níveis de enzima mais levedura na dieta de bovinos sobre a digestibilidade aparente dos nutrientes e o desempenho em confinamento, utilizando-se 18 animais machos, mestiços, de origem leiteira, com peso vivo (PV) médio de 190±10 kg e 12 meses de idade, e 27 animais da raça Guzerá com PV médio de 325 kg e idade média de 27 meses. Os níveis de enzima mais levedura foram zero (controle), 5 g de enzima (E) mais 5 g de levedura (L) e 10 g de E mais 5 g de L por animal por dia. Todos os animais receberam a mesma dieta, constituída de 65% de silagem (50% de milho:50% de sorgo) e 35% de concentrado composto de milho (24,6%), farelo de algodão (7,4%), uréia (1,2%), sal mineralizado (0,54%) e calcário (0,86%). Esta dieta apresentava 12,4% de PB; 10,1 MJEM/kg MS e 41,1% de FDN. A adição de enzima mais levedura não alterou o consumo de MS (3,31% do PV ou 126,6 g/kg PV0,75), e CDA da MS (63,0%), PB (68,2%), EE (83,3%), CHOT (61,3%), FDN (47,2%), FDA (43,8%) e valor de NDT (62,8%). O GMD e o CMS diminuíram de forma quadrática e a CA alimentar piorou linearmente, em função dos dias de confinamento. O fornecimento de enzima mais levedura para bovinos de corte não traz benefícios nutricionais ou de desempenho.

The objetive of this work was to evaluate the effect of the addition of different enzyme levels plus yeast in the cattle diet on apparent nutrient digestibility and cattle performance in feedlot. Is was used 18 crossbred bulls (Taurino x Zebuino) of milk dairy origin with average LW of 190±10 kg and age of 12 months and 27 steer of the Guzerá breed with LW and age of 325 kg and 27 months. The levels of enzyme plus yeast were zero (control), 5 g of enzyme (E) plus 5 g of yeast (Y) and 10 g E plus 5 g Y for animal day. All animals received the identical diet with 65% silage (50% corn:50% sorghum) and 35% of concentrate composed of corn (24.6%), cottonseed meal (7.4%), urea (1.2%), mineralized salt (.54%) and limestone (.86%). This diet showed 12.4% CP, 10.1 MJ ME/kg DM and 41.1% NDF. The enzyme plus yeast did not affected DM intake (3.3% LW or 126.6 g/kg LW.75) and ACD of DM (63.3%), CP (68.2%), EE (83.3%), TCHO (61.3%), NDF (47.2%), ADF (43.8%), and TDN value (62.8%). The ADG and DMI decreased of quadratic form and feed:gain ratio worsed linearly, in function of feedlot days. The feeding of enzyme plus yeast for beef cattle did not bring nutritional and performance benefits.