Lagrangian statistics from millions of particles are used to study the turbulent entrainment mechanism in a direct numerical simulation of a turbulent plane jet at Re(λ) ≈ 110. The particles ...(tracers) are initially seeded at the irrotational region of the jet near the turbulent shear layer and are followed as they are drawn into the turbulent region across the turbulent-nonturbulent interface (TNTI), allowing the study of the enstrophy buildup and thereby characterizing the turbulent entrainment mechanism in the jet. The use of Lagrangian statistics following fluid particles gives a more correct description of the entrainment mechanism than in previous works since the statistics in relation to the TNTI position involve data from the trajectories of the entraining fluid particles. The Lagrangian statistics for the particles show the existence of a velocity jump and a characteristic vorticity jump (with a thickness which is one order of magnitude greater than the Kolmogorov microscale), in agreement with previous results using Eulerian statistics. The particles initially acquire enstrophy by viscous diffusion and later by enstrophy production, which becomes "active" only deep inside the turbulent region. Both enstrophy diffusion and production near the TNTI differ substantially from inside the turbulent region. Only about 1% of all particles find their way into pockets of irrotational flow engulfed into the turbulent shear layer region, indicating that "engulfment" is not significant for the present flow, indirectly suggesting that the entrainment is largely due to "nibbling" small-scale mechanisms acting along the entire TNTI surface. Probability density functions of particle positions suggests that the particles spend more time crossing the region near the TNTI than traveling inside the turbulent region, consistent with the particles moving tangent to the interface around the time they cross it.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
This exploratory paper addresses the relationship of science journalism, science communication, environmental activism, and social movements. It draws on data from Latin America, exploring how ...journalists and activists use science communication as a tool for telling stories about environmental conflicts that frequently turn violent (more than 1600 land and environmental activists lost their lives between 2002 and 2020 in Latin America, more than three times that of all other regions of the world combined). The main goal of the paper is to understand how scientific storytelling by NGOs helps them present their points of view for journalists and to influence public opinion. Our data is drawn from the formal reports of four NGOs and from semi-structured interviews with representatives from each NGO's staff about their use of science communication. Our analysis suggests that Latin American NGOs use science communication tools such as scientific storytelling and scientific explanation to support journalists and to communicate with broad publics about complex phenomena such as socio-environmental conflicts, contributing to efforts to reduce the alarming amount of violence in the region.
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BFBNIB, NUK, PILJ, SAZU, UL, UM, UPUK
Thymol is an herbal food additive used to improve animal performance. Thymol acts via its potential to enhance productive and reproductive performance, and by improving bioavailability of nutrients ...in fish. Nevertheless, the exact mechanisms associated with these phenomena remain poorly understood, although recent evidence has suggested the involvement of the phosphotransfer network and antioxidant status. Therefore, the aim of this study was to determine whether the improvement of the antioxidant/oxidant status and the phosphoryl transfer network may be involved in enhanced growth performance in grass carp (
Ctenopharyngodon idella
) fed with various levels of thymol (100, 200, and 300 mg/kg feed). Thymol-supplementation (100 mg/kg feed) produced higher body weight and weight gain for 60-day post-feeding compared to the control group. Specific growth rate was higher; while feed conversion ratio was lower in fish that consumed 100 mg of thymol/kg compared to other groups. Hepatic lactate dehydrogenase activity and lipid peroxidation levels were lower in the thymol-supplemented group (100 mg/kg feed) than in the control group, while reactive oxygen species were lower in all supplemented groups than in the control group. Hepatic superoxide dismutase (300 mg/kg feed) and glutathione peroxidase (100, 200, and 300 mg/kg feed) activities, as well as antioxidant capacity against peroxyl radicals (100 mg/kg feed) were higher in these groups than in the control group. Based on these data, we conclude that 100 mg thymol/kg dietary supplementation increased growth performance of fingerling grass carp. Finally, hepatic adenylate kinase activity was lower in the thymol supplemented group (100 mg/kg feed) than in the control group. Thymol supplementation (100 mg/kg feed) improved hepatic energy metabolism, while practically all tested concentrations of thymol enhanced hepatic antioxidant status, all of which may be pathways involved in increased growth performance in fingerling grass carp.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The search for materials made from renewable sources and free from toxic substances is a global trend towards a cleaner production, and this can be extended to the development of wood-based panels. ...World production of wood-based panels in 2014 was 388 million cubic meters, which represents an increase of 34% compared to 2010. However, the industrial sector of wood-based panels has been facing some gaps and challenges regarding the toxic emissions coming from conventional adhesives applied to the manufacture of panels. Faced with these problems, the aim of this study was to assess the technical feasibility and environmental aspects of manufacturing a particleboard made with wood waste and epoxy based ink-waste as adhesive. To this end, the particleboard reinforcement phase was made of particles of wood waste of Pinus sp. and Teak (Tectona grandis) species, while residual ink resin-based epoxy was used as alternative adhesive to reduce demand for urea formaldehyde resin. Particleboards were manufactured and tested by varying some production parameters, namely: low, medium and high-density panel classifications; 20, 30 and 40% epoxy resin content; and mixture of Pinus and Teak wood waste particles from 0, 25, 50, 75, 100%. Physical-mechanical performance of the manufactured particleboards were evaluated according to ABNT NBR 14810 (2013) and ANSI A208.1 (2009) Standard Codes. Statistical analyzes based on Analysis of variance (ANOVA) were used to test the influence of each individual factor (density, adhesive percentage and fraction of Pinus/Teak particles) and their interactions under the physical-mechanical properties. Results showed a satisfactory performance in terms of physical and mechanical properties for treatments with high density (up to 0.80 g/cm³), 30–40% epoxy based ink-waste adhesive and 50–100% Teak wood particles. In most of the cases, the evaluated properties were superior to the compared requirements available at Standard Codes. Finally, it was developed an environmental performance of the particleboards based on a simplified Life Cycle Assessment (LCA) method, and results highlighted some positive environmental aspects as well as social-economic benefits, especially for suppliers of wood waste and resin epoxy residues, and also due to minimization of air releases of free formaldehyde and energy consumption in the production of panels.
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•Cleaner production based on a proposal of a new model of particleboard.•Technical and environmental analyzes of the proposed particleboards.•Possibility of using the proposed particleboard model by furniture industries.•Savings on resources consumption to produce the particleboard model in Brazil.•Contributions of the developed particleboard model for a Circular Economy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The objective of the present work was to investigate different dietary digestible protein (22%, 26% and 30% of DP) and digestible energy (3000, 3150 and 3300 kcal DE kg−1) levels on growth ...performance and hematological parameters of Genetically Improved Farmed Tilapia (GIFT) fingerlings (0.99 ± 0.1 g of mean initial weight) over 42 days. In addition, proximate analysis of carcass and biofloc biomass, as well as planktonic community characterization were performed. A factorial design (digestible protein and digestible energy as factors) was applied totaling nine treatments with four replicates each. The FCR (~1.17) and survival (>98%) were similar between all treatments (P > .05). When assessing the final weight of the fish, in terms of weight gain and specific growth rate, the 22% and 26% DP treatments were not affected by the energy level (P > .05); however, the 30% DP level were affected by energy levels (P < .05) with best results using 3150 kcal DE kg−1. In regard to somatic parameters, carcass yield and condition factor of the fish were similar between all treatments (P > .05). Standard length presented an interaction effect (P < .05); while total length and the hepatosomatic index were affected by protein levels. Hematological parameters showed variability according to different dietary protein levels while carcass proximate composition was affected by both protein and energy levels (P < .05). The monitoring of planktonic communitities indicated some variation over the duration of the experiment, specifically on the number of dinoflagellates, rotifers and protozoa groups. These results suggest that the optimal digestible protein and digestible energy levels for tilapia fingerlings raised in freshwater biofloc systems are 26% DP and 3000 kcal DE kg−1.
•Digestible protein and digestible energy levels can be reduced in GIFT tilapia raised in freshwater BFT system.•Hematological parameters showed differences according to different dietary protein levels.•Carcass proximate composition were affected by both protein and energy levels.•Planktonic community fluctuated over time specially on dinoflagellates, rotifers and protozoa numbers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This article discusses a study on reverse logistics in which a returnable packaging model was developed in order to minimize waste generation and increase the competitiveness of the company studied ...by reducing costs and resource consumption and minimizing environmental impacts. The objective of this study is to present a case study on reverse flow of returnable packaging to replace a disposable packaging system used by a company located in Joinville, Santa Catarina, Brazil to export machined engine heads to Peterborough, UK. As a result, the returnable packaging model consumed 18.00% less material than the disposable packaging model, reducing costs. Furthermore, the model developed provided greater protection to the products exported and minimized waste generation at the final customer. Other logistic benefits were reduction in the volume occupied and weight of empty packaging during reverse flow and a cycle time of 105 days. Additionally, the unit cost of the returnable packaging was R$ 13.57 per engine head, a satisfactory outcome for the company studied. With regard to environmental performance, the returnable packaging model proved the best alternative since it has less environmental impacts compared to those of the disposable packaging model. The practice of reverse logistics has shown benefits that contribute technically, economically, and environmentally to business sustainability.
► We proposed a system of reverse logistics using a returnable packaging model. ► The returnable packaging model was compared with a disposable packaging model. ► Technical and environmental analyses were made comparing the two packaging models. ► The returnable packaging showed 18.00% less consumption of material reducing costs. ► The returnable packaging showed satisfactory environmental performance results.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Use and production of industrialized wood based panels is increasing in Brazil and one of the outstanding products is the Oriented Strand Boards (OSB). At the same time, environmental concerns by ...companies and society about products and production systems are also growing, and the current study aims to assess the environmental impacts associated to the Brazilian OSB production in order to propose improvement alternatives focused on their profile's enhancement. Thus, a Life Cycle Assessment (LCA) study was performed according to ISO14040 and 14044 frameworks. The study covers the life cycle of OSB production from a cradle-to-gate perspective and considering real practices carried out in a representative Brazilian company. The production system has been divided in two main subsystems: Forest operations (SS1) and Panel factory (SS2). The environmental profiles have been reported considering characterization factors from the ReCiPe method, in terms of nine impact categories: climate change (CC), ozone depletion (OD), terrestrial acidification (TA), freshwater eutrophication (FE), marine eutrophication (ME), human toxicity (HT), photochemical oxidant formation (POF), terrestrial ecotoxicity (TET), freshwater ecotoxicity (FET), fossil depletion (FD). According to the results, the industrial activities carried out within SS2 have been identified as the largest responsible of contributions to all impact categories under assessment. The production of pyrethroid termiticide, which is applied in the panels to improve their resistance to attack by wood decay organisms, was the largest contributor to OD, FE, HT and FET. Scenarios based on the substitution of pyrethroid termiticide were proposed and results showed that substituting the pyrethroid termiticide by different types of boron based termiticides could lead to reduce environmental impacts up to 35%. The identification of the main environmental hotspots in the OSB cradle-to-gate life cycle can assist the Brazilian industry to improve its environmental profile by adopting the proposed scenarios for SS2. Finally, further research should be focused on exploring more types of termiticides that can be applied in the OSB panel.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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The application of hot melt coating (HMC) as an economic and solvent-free technology is restricted in pharmaceutical development, due to the instable solid-state of HMC excipients ...resulting in drug release instability. We have previously introduced polyglycerol esters of fatty acids (PGFAs) with stable solid-state (Part 1). In this work we showed a novel application of PGFAs as HMC excipients with stable performance. Three PGFA compounds with a HLB range of 5.1–6.2 were selected for developing immediate-release formulations. The HMC properties were investigated. The viscosity of molten lipids at 100 °C was suitable for atomizing. The DSC data showed the absence of low solidification fractions, thus reduced risk of agglomeration during the coating process. The driving force for crystallization of selected compounds was lower and the heat flow exotherms were broader compared to conventional HMC formulations, indicating a lower energy barrier for nucleation and lower crystallization rate. Lower spray rates and a process temperature close to solidification temperature were desired to provide homogeneous coating. DSC and X-ray diffraction data revealed stable solid state during 6 months storage at 40 °C. API release was directly proportional to HLB and indirectly proportional to crystalline network density and was stable during investigated 3 months. Cytotoxicity was assessed by dehydrogenase activity and no in vitro cytotoxic effect was observed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study aimed to evaluate the effect of the biofloc technology (BFT) system and the replacement of fish meal with Spirulina biomass on productive performance, intestinal histomorphometry, plasma ...biochemistry, and oxidative stress of Nile tilapia juveniles (Oreochromis niloticus) fed suboptimal levels of protein. Two factors were evaluated: production systems (clear water × BFT) and replacement of fish meal with Spirulina (0, 33, 66 e 100%). The design was in a 2 × 4 randomized factorial scheme with four replications, and the fish were evaluated for 48 days. Four isoproteic (28% crude protein) diets were formulated with gross energy values close to 4300 kcal kg
. Nile tilapia juveniles (0.23 ± 0.01 g) were distributed in 16 circular tanks (70 L) at seven fish/tank. The diets were formulated with protein levels approximately 20% below that required for the species and life stage. No interaction was observed between the factors evaluated (production systems × Spirulina inclusion). Rearing the fish in the BFT system avoided the adverse effects of diets with suboptimal protein levels on performance, intestinal histomorphometry, and protein metabolism. Lower values lower lipid peroxidation and higher antioxidant capacity were observed in fish reared in the BFT system, showing evidence of improvements in antioxidant responses and lower levels of physiological oxidative stress. Spirulina completely replaced fish meal in the diets of Nile tilapia juveniles without adverse effects on intestinal morphometry, protein metabolism, and antioxidant response. Replacing 66% of fish meal with Spirulina improved the productive performance, regardless of the rearing system.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Toxic metals as arsenic (As), cadmium (Cd), nickel (Ni), and lead (Pb) exist in the atmosphere as particulate matter components. Their concentration levels in the European Union (EU) are regulated by ...European legislation, which sets target and limit values as annual means, and by the World Health Organization (WHO) that defines guidelines and reference values for those metal elements. Modelling tools are recommended to support air quality assessment regarding the toxic metals; however, few studies have been performed and those assessments rely on discrete measurements or field campaigns. This study aims to evaluate the capability of air quality modelling tools to verify the legislation compliance concerning the atmospheric levels of toxic elements and to identify the main challenges and limitations of using a modelling assessment approach for regulatory purposes, as a complement to monitoring. The CAMx air quality model was adapted and applied over Porto and Lisbon urban regions in Portugal at 5 × 5-km
2
and 1 × 1-km
2
horizontal resolution for the year 2015, and the results were analysed and compared with the few measurements available in three locations. The comparison between modelled and measured data revealed an overestimation of the model, although annual averages are much lower than the regulated standards. The comparison of the 5-km and 1-km resolutions’ results indicates that a higher resolution does not necessarily imply a better performance, pointing out uncertainties in emissions and the need to better describe the magnitude and spatial allocation of toxic metal emissions. This work highlighted that an increase of the spatial and temporal coverage of monitoring sites would allow to improve the model design, contribute to a better knowledge on toxic metals atmospheric emission sources and to increase the capacity of models to simulate atmospheric particulate species of health concern.
