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This study aimed to investigate the relationship between pre-slaughter factors and major causes of total or partial carcass condemnation in a broiler slaughterhouse under federal inspection. Data on total and partial carcass condemnations between 2018 and 2020 were collected from 10 broiler farms supplying a slaughterhouse located in northern Paraná State, Brazil. The total sample comprised 2,562,642 birds. The pre-slaughter factors analyzed were age at slaughter, stocking density, weight at slaughter, feed conversion, and mortality.Associations between causes of condemnation and pre-slaughter factors were analyzed using a generalized linear model with negative binomial distribution, a generalized linear model with quasi-Poisson distribution, and a generalized linear mixed model with Poisson distribution. Total carcass condemnations were mostly due to repugnant appearance (48.67%) and arthritis (26.56%), whereas partial carcass condemnations were mainly due to arthritis (31.02%), bruising (27.97%), and myopathies (15.18%). Mean age and stocking density were the pre-slaughter factors that most contributed to increasing total and partial condemnation rates, indicating that reducing stocking density and age at slaughter might be important strategies for minimizing economic losses associated with carcass condemnation.(AU)

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This work focuses on the treatment of gaseous perchloroethylene (PCE) using electro-scrubbing with diamond electrodes and cobalt mediators. PCE was obtained by direct desorption from an aqueous solution containing 150 mg L-1, trying to a real pollution case. The electro-scrubber consisted of a packed absorption column connected with an undivided electrochemical cell. Diamond anodes supported on two different substrates (tantalum and silicon) were used and the results indicated that Ta/BDD was more successful in the production of Co (III) species and in the degradation of PCE. Three experimental systems were studied for comparison purposes: absorbent free of Co (III) precursors, absorbent containing Co (III) precursors, and absorbent containing Co (III) precursors undergoing previous electrolysis to the electro-scrubbing to facilitate the accumulation of oxidants. The most successful option was the last, confirming the important role of mediated electrochemical processes in the degradation of PCE. Trichloroacetic acid (TCA) and carbon tetrachloride (CCl4) were found as the primary reaction products and ethyl chloroacetate esters were also identified. A comprehensive mechanism of the processes happening inside electro-scrubber is proposed.

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Four different technologies have been compared (photolysis, ZVI + photolysis, electrolysis and ZVI + electrolysis) regarding the: (1) degradation of clopyralid, (2) extent of its mineralization, (3) formation of by-products and main reaction pathways. Results show that photolysis is the less efficient treatment and it only attains 5 % removal of the pollutant, much less than ZVI, which reaches 45 % removal and that electrolysis, which attains complete removal and 78 % mineralization within 4 h. When ZVI is used as pre-treatment of electrolysis, it was obtained the most efficient technology. The identification of transformation products was carried out for each treatment by LCMS. In total, ten products were identified. Tentative pathways for preferential clopyralid degradation for all processes were proposed. This work draws attention of the synergisms caused by the coupling of techniques involving the treatment of chlorinated compound and sheds light on how the preferential mechanisms of each treatment evaluated occurred.

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In this work, it is studied a wind-powered electrokinetic soil flushing process for the removal of pesticides from soil. This approach aims to develop an eco-friendly electrochemical soil treatment technique and to face the in-situ treatment of polluted soils at remote locations. Herbicide 2,4 dichlorophenoxyacetic acid (2,4-D) is selected as a model pollutant for the soil treatment tests. The performance of the wind-powered process throughout a 15 days experiment is compared to the same remediation process powered by a conventional DC power supply. The wind-powered test covered many different wind conditions (from calm to near gale), being performed 20.7% under calm conditions and 17% under moderate or gentle breeze. According to the results obtained, the wind-powered soil treatment is feasible, obtaining a 53.9% removal of 2,4-D after 15 days treatment. Nevertheless, the remediation is more efficient if it is fed by a constant electric input (conventional DC power supply), reaching a 90.2% removal of 2,4-D with a much lower amount of charge supplied (49.2 A h kg(-1) and 4.33 A h kg(-1) for wind-powered and conventional) within the same operation time.

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In the search for greener treatment technologies, this work studies the coupling of a wind turbine energy supply with an electrolytic cell (CWTEC device) for the remediation of wastewater polluted with pesticide 2,4-dichlorophenoxyacetic acid (2,4-D). The discontinuous and unforeseeable supply of energy is the main challenge inspiring this new proposal, which aims at reducing the environmental impact of electrolytic treatment by using a green energy supply. The results obtained using the coupled technologies are compared with those obtained by powering the electrolyser with a traditional power supply with a similar current intensity. The mineralisation of wastewater can be accomplished independently of how the electrolytic cell is powered, although differences in performance are clearly observed in the total organic carbon (TOC) and 2,4-D decays. These changes can be explained in terms of the changing profile of the current intensity, which influences the concentrations of the oxidants produced and thereby the mediated electrolytic process.

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In this work we have studied the treatment of imazapyr by electrochemical oxidation with boron-doped diamond anode. Electrochemical degradation experiments were performed in a one-compartment cell containing 0.45 L of commercial formulations of herbicide in the pH range 3.0-10.0 by applying a density current between 10 and 150 mA cm(-2) and in the temperature range 25-45 °C. The maximum current efficiencies were obtained at lower current densities since the electrochemical system is under mass transfer control. The mineralization rate increased in acid medium and at higher temperatures. The treatment was able to completely degrade imazapyr in the range 4.6-100.0 mg L(-1), although the current charge required rises along with the increasing initial concentration of the herbicide. Toxicity analysis with the bioluminescent bacterium Vibrio fischeri showed that at higher pollutant concentrations the toxicity was reduced after the electrochemical treatment. To clarify the reaction pathway for imazapyr mineralization by OH radicals, LC-MS/MS analyses we performed together with a theoretical study. Ions analysis showed the formation of high levels of ammonium in the cathode. The main final products of the electrochemical oxidation of imazapyr with diamond thin film electrodes are formic, acetic and butyric acids.

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Large-bodied arthropods, such as cicadas, can be able to reallocate significant amounts of nutrients during adult emergence. Evidence suggests that Quesada gigas Olivier emergence constitutes an important nutrient flux from belowground to aboveground. The purpose of this study was to estimate the amount of nitrogen, proteins, and lipids resulting from the emergence of Q. gigas in an urban ecosystem in Central Brazil. Adult specimens captured from September to November 2006 were weighed and submitted to biochemical analysis. Population density was approximately 4,200 individuals per hectare. Mean individual dry mass was 1.03 g and contained 12.6% proteins, 8.4% lipids, and 5% nitrogen. Total biomass input from the species was 4.3 kg ha(-1) y(-1), with a consequent annual reallocation of approximately 545 g of proteins, 363 g of lipids, and 216 g of nitrogen per hectare. The data obtained suggest that Q. gigas emergence can cause significant translocation of nutrients from belowground to aboveground, and is therefore an important biological event for ecosystem function.

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Artificial ponds or irrigated systems scattered throughout farmlands can offer important habitats for anurans and can be interesting sites for research on species resources use in a changing landscape. This study describes the diet and resource partitioning among anurans inhabiting irrigated rice fields in the Pantanal region. Twenty categories of prey were found in the stomachs of Leptodactylus chaquensis, L. elenae, L. podicipinus and Rhinella bergi, the most frequent being Coleoptera, Hymenoptera, larvae of Hexapoda, Hemiptera, Diptera and Orthoptera. The great differences found in the diet of these species in rice fields compared to other locations, according to available records in the literature, was the increased importance of Hemipitera and Orthoptera and the decrease in importance of Hymenoptera in the diet of leptodactylids. These differences might be attributed to changes in the availability of resources in response to habitat modification. Although diet composition was very similar among species, niche overlap was larger than expected by chance, suggesting that the competition for food resources is not, or has not been, a significant force in determining the structure of this frog community. Two non-exclusive hypotheses could be considered as a justification for this result: 1) the high niche overlap could result from resource availability, which is sufficient to satisfy all species without any strong competition; 2) or the high values of niche overlap could be a selective force driving species to compete, but there has not been enough time to express a significant divergence in the species diet because the study area is characterised as a dynamic habitat influenced by frequent and cyclical changes.

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Artificial ponds or irrigated systems scattered throughout farmlands can offer important habitats for anurans and can be interesting sites for research on species resources use in a changing landscape. This study describes the diet and resource partitioning among anurans inhabiting irrigated rice fields in the Pantanal region. Twenty categories of prey were found in the stomachs of Leptodactylus chaquensis, L. elenae, L. podicipinus and Rhinella bergi, the most frequent being Coleoptera, Hymenoptera, larvae of Hexapoda, Hemiptera, Diptera and Orthoptera. The great differences found in the diet of these species in rice fields compared to other locations, according to available records in the literature, was the increased importance of Hemipitera and Orthoptera and the decrease in importance of Hymenoptera in the diet of leptodactylids. These differences might be attributed to changes in the availability of resources in response to habitat modification. Although diet composition was very similar among species, niche overlap was larger than expected by chance, suggesting that the competition for food resources is not, or has not been, a significant force in determining the structure of this frog community. Two non-exclusive hypotheses could be considered as a justification for this result: 1) the high niche overlap could result from resource availability, which is sufficient to satisfy all species without any strong competition; 2) or the high values of niche overlap could be a selective force driving species to compete, but there has not been enough time to express a significant divergence in the species diet because the study area is characterised as a dynamic habitat influenced by frequent and cyclical changes.(AU)

Lagoas artificiais e sistemas irrigados em áreas de produção agrícola podem oferecer habitats importantes a anuros e ser significativos para investigações sobre o uso de recursos pelas espécies em ambientes modificados. Este estudo descreve a dieta e partição de recursos tróficos entre anuros de campos de rizicultura na região do Pantanal. Nos estômagos de Leptodactylus chaquensis, L. elenae, L. podicipinus e Rhinella bergi foram encontradas 20 categorias de presas, sendo Coleoptera, Hymenoptera, larvas de Hexápoda, Hemiptera, Diptera e Orthoptera as mais frequentes. Maiores diferenças encontradas na dieta dessas espécies em campos de arroz comparadas a de outros locais, de acordo com dados da literatura, foram o aumento da importância de Hemipitera e Orthoptera e a diminuição na importância de Hymenopteras na dieta dos leptodactilídeos. Essas diferenças talvez sejam reflexos de mudanças na disponibilidade de recursos de presas, em resposta às modificações ambientais. Apesar de as espécies apresentarem dietas bastante similares, a sobreposição de nicho foi maior que a esperada ao acaso, sugerindo que a competição por recursos alimentares não é, ou não tem sido, uma força significante na determinação na estrutura dessa comunidade de anuros. Duas respostas não exclusivas podem ser consideradas para justificar esse resultado: 1) a alta sobreposição de nicho poderia resultar da grande disponibilidade de recursos alimentares, a qual seria suficiente para satisfazer as necessidades de todas as espécies sem que haja forte competição; 2) ou os altos valores de sobreposição poderiam ser uma força seletiva que levasse as espécies à competição, mas que não têm tempo suficiente para se expressar em divergência na dieta das espécies pelo fato de a área de estudo ser um ambiente altamente dinâmico, sofrendo bruscas e cíclicas mudanças.(AU)

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Recycling of industrial wastes and by-products can help reduce the cost of waste treatment prior to disposal and eventually preserve natural resources and energy. To assess the recycling potential of a given waste, it is important to select a tool capable of giving clear indications either way, with the least time and work consumption, as is the case of modelling the system properties using the results obtained from statistical design of experiments. In this work, the aggregate reclaimed from the mud that results from washout and cleaning operations of fresh concrete mixer trucks (fresh concrete waste, FCW) was recycled into new concrete with various water/cement ratios, as replacement of natural fine aggregates. A 3(2) factorial design of experiments was used to model fresh concrete consistency index and hardened concrete water absorption and 7- and 28-day compressive strength, as functions of FCW content and water/cement ratio, and the resulting regression equations and contour plots were validated with confirmation experiments. The results showed that the fresh concrete workability worsened with the increase in FCW content but the water absorption (5-10 wt.%), 7-day compressive strength (26-36 MPa) and 28-day compressive strength (32-44 MPa) remained within the specified ranges, thus demonstrating that the aggregate reclaimed from FCW can be recycled into new concrete mixtures with lower natural aggregate content.

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