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The study presented in this paper consists of a grouping of methods for determining numerical solutions to the Poisson equation (heat diffusion) with high accuracy. We compare the results obtained with classical second-order finite difference method (CDS-2) with fourth-order compact (CCDS-4) and the exponential methods (EXP-4). We accelerate the convergence of the numerical solutions using the geometric multigrid method and then apply the completed Richardson extrapolation (CRE) across the full temperature field. This proposed clustering determined solutions with two orders of accuracy higher for all three methods presented in the study, in addition to recommending the EXP-4 method together with CRE for its accuracy and low computational effort. The evidence for our results was established through qualitative verification, through the assessment of orders of accuracy of the discretization error; and quantitative verification, through the analysis of CPU time and complexity order of the numerical solutions calculated. The numerical solutions of sixth-order of accuracy obtained after proposed CRE methodology using the CCDS-4 and EXP-4 methods are recognized as benchmark solutions for these two classes of methods. [ABSTRACT FROM AUTHOR]

In this work, N-alkylated tetrazole copolymers were prepared to produce the solid polymeric electrolytes StVTz-82, StVTz-82:4C, StVTz-82:6C, StVTz-82:8C and StVTz-82:sultone. The chemical structure was confirmed by FTIR, H NMR, C NMR and GPC. GPC thermal analysis showed that the membranes are thermally stable up to 160 °C. DSC was used to evaluate the structural effect on the Tg value. Water absorption (WU) and ion exchange capacity (IEC) were conducted for all electrolytes. We observed a decrease in the elastic modulus with the introduction of side alkyl chains linked to the tetrazole heterocycle. The ionic conductivity of these materials was studied by electrochemical impedance spectroscopy. We observed that the StVTz-82 and StVTz-82:sultone copolymers, in hydrated conditions and at room temperature, are the ones that present the best conductivity values 2.09 and 9.78 mS. cm, respectively. Relating to the hydration number (λ), the StVTz-82:sultone electrolyte has a higher λ value. It also has sulfonic acid group, which has a lower pKa value (~ 1.9) then tetrazole (~ 4.50). From the point of view of mechanical properties, the StVTz-82:sultone electrolyte has a rigidity modulus intermediate to that of StVTz-82, which is more rigid, and StVTz-82:8C, which is the most flexible. These characteristics provide suitable properties for use of StVTz-82:sultone as a solid electrolyte for power generation devices such as fuel cells and batteries. [ABSTRACT FROM AUTHOR]

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This study aimed to construct hydrogel filaments of varying diameters and investigate their behavior over time. Hydrogels were synthesized using different concentrations of sodium alginate and gelatin. The wet spinning technique was employed to produce the hydrogel filaments, utilizing syringes with varying needle sizes and calcium chloride as a crosslinking agent. The filaments were subjected to electromechanical tensile testing to assess their mechanical strength. Additionally, degradation tests were conducted in water to evaluate the porosity of the hydrogel material. The results showed that filaments produced with larger gauge needles exhibited higher electromechanical traction and reduced elongation, while those produced with smaller gauge needles displayed lower resistance to traction but higher stretchability. Storage time did not significantly impact the behavior of the filaments, indicating their durability over time. Moreover, the swelling and degradation tests demonstrated that hydrogels with higher sodium alginate concentrations absorbed liquid faster and degraded more slowly, whereas those with lower gelatin concentrations absorbed liquid more slowly but degraded at a faster rate. In conclusion, the developed hydrogel filaments exhibited varying electromechanical strengths depending on their diameters. Furthermore, they retained their properties over time and their absorption and degradation characteristics were influenced by the composition of the hydrogel material. [ABSTRACT FROM AUTHOR]

To evaluate the effect of ultrasonic activation of the endodontic sealer on its intratubular penetration and bond strength to irradiated root dentin. Forty human teeth were distributed into 4 groups (n = 10), according to the radiation therapy (RT) exposure—70 Gy—and ultrasonic activation (UA) of the endodontic sealer: RT/UA—irradiated teeth and sealer UA; RT/no-UA—irradiated teeth and no sealer UA; no-RT/UA—non-irradiated teeth and sealer UA and no-RT/no-UA—non-irradiated teeth and no sealer UA. Push-out bond strength test was performed in a Universal Testing Machine. Failure modes and adhesive interface were analyzed under Scanning Electron Microscopy. The data were statistically compared (two-way-ANOVA and posthoc Games-Howell test; Fisher's exact test − α = 5%). The different experimental conditions (radiation and UA) and the root third had a significant effect on push-out bond strength, and the interaction of these factors was significant (p < 0.05). UA of the sealer significantly increased its bond strength to both irradiated and non-irradiated dentin (p < 0.05). The irradiated groups mostly presented adhesive-type failure of the sealer (p < 0.01). Regardless of the irradiation, the ultrasonically activated groups showed a more homogeneous adhesive interface, with the presence of sealer tags in greater density and depth. Ultrasonic activation enhanced the intratubular penetration and the bond strength of the endodontic sealer to irradiated dentin. The impact of ultrasonic activation of the endodontic sealer on teeth undergoing radiotherapy is a gap in the scientific literature that needs to be bridged. [ABSTRACT FROM AUTHOR]

People with speech and motor impairments may experience difficulties in interaction and learning, among other situations that can lead to emotional, social, and cognitive problems. Augmentative and alternative communication (AAC) is a research area that involves using non-oral modes as a complement or substitute for spoken language. The AAC supported by computer vision (CV) systems can benefit from recognizing the user's remaining functional movements as an alternative design approach to interaction. The complete MyPGI, Methodology to yield Personalized Gestural Interaction, is presented. MyPGI guides the design of AAC systems for people with motor and speech difficulties, using CV techniques and machine learning to enable personalized and noninvasive gestural interaction. The MyPGI methodology was used to develop an AAC system, named PGCA (Personal Gesture Communication Assistant), employing a low-cost approach, used in experiments conducted with volunteers, including students with motor and speech difficulties. Experiments, interviews, and usability evaluation were conducted to evaluate the feasibility of the methodology and the system developed. The results suggest the methodology as promising to support the design of AAC systems capable of enabling personalized gestural interaction, also showing benefits of this approach, technical challenges, and means to overcome them. The results also add knowledge about specific challenges and needs of the target audience. The MyPGI methodology, developed after several iterations and evaluations, is capable to support the design of AAC systems that enable personalized gestural interaction. This article presents an overview of the methodological steps performed, results obtained, and future perspectives for the methodology. [ABSTRACT FROM AUTHOR]

The alarming release of pollutants into aquatic ecosystems, particularly concerning the emission of antibiotics, demands attention. Tetracycline (TC) is a drug commonly identified in both industrial and residential wastewater. In this context, new perovskite-type catalysts are considered a relevant topic for antibiotic degradation in water. The focus on oxides with a perovskite-like structure is due to their impressive thermal stability, cost-effectiveness, enhanced oxygen mobility, and flexibility for structural modifications. In this study, perovskite-type catalyst based on strontium and copper was synthesized and successfully applied in the TC degradation in absence of light. The material was prepared via sol-gel using a temperature controlled jacketed reactor. Numerous characterization techniques were applied to infer the catalyst's chemical and morphological aspects (TEM, SEM, XRD, BET, FTIR, and EDX). The material presented a dense characteristic and low porosity aspects. Also, the specific surface area and average pore diameter measured for the catalyst were 0.572 m2 ∙ g−1 and 37.76 nm, respectively. In the degradation tests, no substance was added to assist in the treatment, which obtained excellent removal percentages over a wide pH range. Degradation yields achieved for pHs 4, 6, 7, and 10 were 94.3, 92.8, 92, and 90.4%, respectively. In addition, studies on surface adsorption, stability, phytotoxicity, main active species, and intermediates to assess the catalyst's performance were realized. Highlights: Perovskite-type strontium and copper-based catalyst was applied in TC degradation through dark catalysis; TC degradation was successful over a wide pH range (>90%); Study on active species and surface adsorption were performed; Catalyst showed high performance in the reuse cycles; [ABSTRACT FROM AUTHOR]

This study reported the effects of adding red ceramic waste in the production of composites with PU as a thermal insulator. The composites were characterized for chemical structure by FTIR, morphology by SEM and OM, thermal stability with TGA, and the mechanical properties, water absorption, and thermal conductivity were verified. For this purpose, composites were prepared to contain 10–30% red ceramic residue powder (brick) in the PU matrix and PU without residue. The composites presented similar thermal stability to the PU, and the FTIR bands of the urethane chemical bonds were verified. The microstructure analysis revealed the formation of a porous structure characteristic of the PU system. However, the increase in the residue concentration led to the formation of heterogeneous and open pores in the structure. This characteristic directly influenced the material properties, reducing compressive strength, Yong modulus, and thermal conductivity values and increasing the water absorption value. The thermal conductivity of all composites was lower than for PU, the best thermal insulation result obtained for the PUCER-10 composition. It is suggested that composite boards be prepared to be used as insulators with the incorporation of a certain amount of waste when seeking the environmental sustainability of the construction industry. [ABSTRACT FROM AUTHOR]

Animal venoms are rich sources of neuroactive compounds, including anti-inflammatory, antiepileptic, and antinociceptive molecules. Our study identified a protonectin peptide from the wasp Parachartergus fraternus' venom using mass spectrometry and cDNA library construction. Using this peptide as a template, we designed a new peptide, protonectin-F, which exhibited higher antinociceptive activity and less motor impairment compared to protonectin. In drug interaction experiments with naloxone and AM251, Protonectin-F's activity was decreased by opioid and cannabinoid antagonism, two critical antinociception pathways. Further experiments revealed that this effect is most likely not induced by direct action on receptors but by activation of the descending pain control pathway. We noted that protonectin-F induced less tolerance in mice after repeated administration than morphine. Protonectin-F was also able to decrease TNF-α production in vitro and modulate the inflammatory response, which can further contribute to its antinociceptive activity. These findings suggest that protonectin-F may be a potential molecule for developing drugs to treat pain disorders with fewer adverse effects. Our results reinforce the biotechnological importance of animal venom for developing new molecules of clinical interest. [ABSTRACT FROM AUTHOR]

Tanneries are considered some of the most polluting industries due to the heavy use of toxic compounds, most of which are released into water bodies, thus exerting adverse effects on aquatic biota. However, the effects on organisms of treated effluents when released into the natural environment are rarely evaluated. This study aims to assess the physicochemical parameters of a tannery effluent after treatment (TE) at a Common Effluent Treatment Plant as well as the water of the receiving stream and to evaluate cytogenotoxic effects in Allium cepa. Three sampling sites (A: TE discharge point; B: 100 m downstream from site A along the receiving stream; C: 100 m upstream from site A along the stream) were selected. Onion bulbs were exposed to TE (100%, 80%, 60% v/v), water samples from sites B and C, and tap water for 72 h. Chromosomal aberration and mitotic index were analyzed on the root cells of A. cepa. The TE was above the standard limits for ammoniacal nitrogen, COD, and total nitrogen. No cytogenotoxicity was observed in A. cepa exposed to samples from sites A and C. However, the stream water sampled downstream from the TE discharge site significantly reduced the mitotic index, indicating a cytotoxic effect. Therefore, this demonstrates the effects of interactions between the receiving water and the complex chemical mixtures in the TE. The findings thus showed that the toxicity assessment of treated effluents along with the receiving water body would provide valuable and more realistic information about the joint toxicity of chemical pollutants in aquatic environments. [ABSTRACT FROM AUTHOR]

This study aimed to apply the comet assay on Aegla platensis crabs as a suitable non-destructive approach for in situ monitoring of freshwater genotoxicity. Animals were captured during four sampling periods in a stream under minor anthropogenic impacts in Southern Brazil. Crabs were captured with a hand net, then the hemolymph samples were collected, and the animals were released into the stream after a 20-min recovery time. Hemolymph samples were transported to the laboratory and used to perform the alkaline comet assay. Results showed an intermediate level in the DNA damage index (range 107.3–165.0 arbitrary unit). No significant differences were observed among the different sampling periods. Hemolymph was successfully used as a non-lethal source of biological samples, and the comet assay using A. platensis proved to be a feasible approach for genotoxicity studies. [ABSTRACT FROM AUTHOR]

The management of activities in an agile environment takes place in iterative and incremental processes, in which people from the development team and other project stakeholders effectively work together to understand a given problem, in addition to keeping priority to activities with the greatest business value for the client. This article aims to understand the competencies of an agile team for managing activities in an agile environment. The systematic literature review was performed by using the Web of Science and Scopus databases, in which 1035 articles were found after the application of filters and criteria for inclusion and exclusion. Next, 320 articles were left for full and in-depth reading, which resulted in 126 articles considered to be valid for research. The articles were categorized by using Excel spreadsheets in order to group the findings and allow the comparison of categories. The results demonstrated four categories regarding (1) competencies, (2) tools, (3) relationship with the activity, and (4) characteristics of the development team. It was also highlighted that the technical competencies of the development team must be used in new tools. As for iterations, it is also necessary to promote a process of managing interpersonal competencies to ensure engagement and the ability to communicate effectively with business people and project members. A model is presented that can be used as a tool to support the planning of activities in an agile environment. The development team must have competencies for using new tools during iteration, given the complexity existing in each activity and the critical relationship of each activity with the finalization phase of the iteration. [ABSTRACT FROM AUTHOR]

The protein requirements of hair sheep are a key factor in increasing profitability and decreasing the environmental impacts of nitrogen excretion. The objective of this study was to evaluate the protein requirements of hair sheep. A database with 382 individual records (269 intact and 113 castrated males) comprising information from 11 studies was used. The studies provided different levels of metabolisable protein intake (MPI) and of N retention, allowing the development of equations to predict the net protein (NP) and the metabolisable protein (MP) requirements. The efficiency of MP use for gain (kpg) was calculated using the equation of daily protein retained against daily MPI above maintenance. The efficiency of MP use for maintenance (kpm) was computed as the ratio between the NP for maintenance (NPm) and the MP for maintenance (MPm). The NPm (1.32 g/kg0.75 EBW) did not differ between sex. The kpm was 0.34, and the kpg was 0.25. The MPm estimated was 3.21 g/kg0.75 BW. Sex affects the protein requirements for gain (NPg). The protein requirements of hair sheep differ from those recommended by feeding systems for sheep. The equations provided herein may improve the optimisation of protein nutrition of sheep, thereby minimising the environmental impacts of sheep production. [ABSTRACT FROM AUTHOR]

Lack of biomaterials feasible for three-dimensional (3D) biofabrication and the limited capability to sterilize some of these items are current gaps that need to be settled to strengthen studies in this area. Silver nanoparticles (AgNPs) are known for their enhanced antimicrobial capability against a great number of microorganisms and consequently have the potential to be applied in areas that need novel sterilization strategies. Therefore, this study aimed to produce hydrogels containing AgNPs in a completely green way with possible applications in 3D bioprinting. AgNPs were synthesized using banana peels and their physico-chemical characteristics were evaluated. Hydrogels were produced using mixtures with different proportions of carboxymethyl cellulose, gelatin, and agar, and were characterized concerning their swelling capability, consistency, and printability. Citric acid (CA) was tested as a sustainable crosslinking agent at different time intervals and concentrations. Lastly, one selected hydrogel was chosen based on performed assays and was prepared with the AgNPs for tests against Gram-negative and Gram-positive bacteria models. From the 36 initial hydrogels, 8 were chosen to be extruded manually based on swelling assay and consistency and, from those, 2 were chosen for 3D bioprinting assays. Finally, one was chosen to be prepared with AgNPs and was used for antibacterial assays. In the crosslinking assay, the best parameter was an exposure of 1 min to CA at a concentration of 5%. Hydrogel + AgNP was effective in inhibiting bacterial growth. Thus, it was produced a nanocomposite biomaterial in a completely green manner with potential applications in 3D biofabrication that presented antibacterial capability. [ABSTRACT FROM AUTHOR]

In the present study, water physicochemical and microbiological parameters, as well as bioassays using Allium cepa L. seeds and the fish species Astyanax jacuhiensis were used to assess the water quality of two rivers – Ilha River and Paranhana River –, located in southern Brazil. Water samples were collected at the source and mouth of the rivers and then, laboratory experiments were performed. The results evidenced high levels of aluminum and iron in water samples collected at the four sampling sites. The micronucleus (MN) test in fish showed significant difference in the frequencies of nuclear abnormalities (NA) in the mouth of the Paranhana River in comparison to control group in one sampling period, whereas the A. cepa test evidenced significant spatial differences in cytotoxicity between the source and mouth of both rivers. Therefore, these data evidence the poor water quality of the rivers studied as well as the potential toxicity to the aquatic organisms. [ABSTRACT FROM AUTHOR]

In this article, we present the results of the composite development obtained from polyurethane (PU), polyvinyl chloride (PVC), and aluminum anodizing sludge (AAS). The composites were prepared in different compositions and the properties were compared with PU. The apparent density, mechanical resistance to compression, thermal stability study (UL94, DSC, calorimetric cone, SEM and DRX) and simulation of the energy use intensity (EUI) by Green Building Studio® (GBS) were analyzed. The specimens showed flame extinction in the horizontal and vertical flammability tests and less loss of mass when associated with AAS to PVC. Microscopy shows that for the flammability test of the composites a ceramic layer was formed due to the presence of AAS, which improved flame retardation and smoke suppression (UL94 and calorimetric cone). EUI for building using construction elements with composite (PVC 40 wt%) was 28% lower than EUI with ceramics, with CO2 and cost reduction. The developed materials can contribute to the construction industry as a safe insulator, saving natural resources. [ABSTRACT FROM AUTHOR]

The purpose of this study is to identify and analyze meanings that the term complexity assumes in Brazilian theses and dissertations in the field of environmental education, especially when addressing socio-environmental issues. The studies were selected from the database Theses and Dissertations of EArte (http://earte.net/), which is a repository for Brazilian theses and dissertations in the field of environmental education. Twenty theses and dissertations were selected to compose the documental corpus of this investigation. For the investigation, content analysis was used. Three a priori categories were defined to analyze the meanings of Complexity: (1) complex thinking: organized from Morin's ideas of Dialogical Principle, Organizational Recursion Principle, Holographic Principle, and Scienza Nuova; (2) complex systems: organized from uncertainty, dynamics, and open systems groupings; and (3) complexification organized from the environmental complexity grouping. The complex thinking category was the most frequent in the analyses, identified in fifteen of the twenty theses and dissertations. In twelve of the twenty dissertations, the category of complex systems was identified, while in four of the twenty, the category complexification was referenced. These studies show a greater inclination towards the ideas of Edgar Morin and Enrique Leff. [ABSTRACT FROM AUTHOR]

Patterns of diversity in pathogen genomes provide a window into the spatiotemporal spread of disease. In this study, we tested the hypothesis that Schistosoma mansoni parasites form genetic clusters that coincide with the communities of their human hosts. We also looked for genetic clustering of parasites at the sub-community level. Our data consists of 14 microsatellite DNA markers, typed from pooled DNA samples from N = 254 infected individuals living in three Brazilian communities. We found a one-to-one correspondence between genetic clusters found by K-means cluster analysis and communities when K = 3 . These clusters are also easily identified in a neighbor-joining tree and principal coordinates plots. K-means analysis with K > 3 also reveals genetic clusters of parasites at the sub-community level. These sub-clusters also appear on the neighbor-joining tree and principal coordinates plots. A surprising finding is a genetic relationship between subgroups in widely separated human communities. This connection suggests the existence of common transmission sites that have wide influence. In summary, the genetic structure of S. mansoni in Brazil juxtaposes local isolation that is occasionally broken by long-range migration. Permanent eradication of schistosomes will require both local efforts and the identification of regional infection reservoirs. [ABSTRACT FROM AUTHOR]

The objective of this study was to obtain and characterize Nerol essential oil encapsulated in PCL. The miniemulsion and solvent evaporation method was used, resulting in PCL-Nerol capsules bonded by a physical interaction, with a dispersity index of 0.101, a particle size of 0.14 µm, and an encapsulation efficiency of 94.27%. In addition, the temperature at which the oil degraded could be observed to increase by 100 °C when it is encapsulated in PCL, revealing this polymer's capacity in working as an encapsulating agent. The PCL-Nerol capsules in suspension proved to be stable for 60 days regarding the pH of the suspensions, mean particle size, dispersity index, zeta potential and the encapsulation efficiency, not presenting clusters and flocculation. The results are considered satisfactory and important for the future industrial applications of the obtained microparticles. [ABSTRACT FROM AUTHOR]

Delonix regia has bioactive phytochemicals present in leaves, seeds, roots, and flowers. Considering that these compounds are common in extracts used for silver nanoparticles (AgNPs) biosynthesis, this study investigated the potential of D. regia seeds aqueous extract (DRE) in different concentrations to produce AgNPs (DRE-AgNPs). DRE composition was investigated by qualitative assays, and physico-chemical/structural characterization of AgNPs was performed by UV–Visible spectroscopy, dynamic light scattering (DLS), Zeta potential, and atomic force microscopy (AFM). Antibacterial effect of DRE-AgNPs was evaluated against Escherichia coli and Staphylococcus aureus. DRE presented mainly tannins and saponins. Additionally, the absorbance of each DRE-AgNPs was positively correlated to DRE concentration. At higher DRE concentrations, AgNPs were larger, regarding Z average; tended to monodispersity; and presented more negative Zeta potentials. Hydrodynamic diameters of DRE-AgNPs were measured by number distribution and only AgNPs synthesized with DRE 2 mg ml−1 (DRE-AgNPs 2) presented a single population of particles. Thus, DRE-AgNP 2 was analyzed by AFM and exhibited a spherical shape and an average height of 18.39 ± 1.59 nm. Most of DRE-AgNPs presented antibacterial effects against E. coli and S. aureus at 128 or 256 µmol l−1. In conclusion, different DRE concentrations modulated physico-chemical characteristics of AgNPs with antibacterial activity. [ABSTRACT FROM AUTHOR]

Minerals play an important role in animal metabolism. Knowledge of mineral requirements allows well-formulated diets to be provided, which is the main factor that affects performance. To determine the macromineral and trace element requirements for growth and maintenance, thirty-eight 2-month-old Santa Ines lambs with initial body weight (BW) of 13.0 ± 1.49 kg were distributed in a factorial design with feeding levels (ad libitum, 30% and 60% feed restriction) and sex classes [castrated (CM) and intact males (IM)]. The net mineral requirements for gain were higher (P < 0.05) with increasing BW and average daily gain, except for Ca and Na, which remained constant as the empty BW (EBW) increased. The macromineral net requirement for maintenance (g/kg EBW0.75) and the true retention coefficient (k; %) were 0.0784 and 65.2 for Ca, 0.0926 and 80.0 for P, and 0.0379 and 59.0 for K, respectively. The k of Mg was higher (P < 0.05) for IM (11.3 for IM and 7.9 for CM). Sex did not affect (P > 0.05) the maintenance requirement of the trace elements Co, Cu, Zn and Cr which were 0.0015, 0.037, 0.698, and 0.0055 (mg/kg EBW0.75), respectively. Our study indicated that the Santa Ines net mineral requirements are different from the main nutritional requirements established by committees for sheep, which may result in unbalanced diets. [ABSTRACT FROM AUTHOR]

It is a well explored facts that need of biosynthesized nanomaterials has emerged for its several advantages in biomedical applications and the search for potential biosynthesized-nanomaterials is still ongoing. In this study an attempt was made to meet the requirement of potential biosynthesized-silver nanoparticles using the aqueous seed extract of N. sativa (Bc-AgNPs). X-ray powder diffraction (XRD) confirms the biosynthesis of silver nanoparticle (supports the observation of UV–Vis spectroscopy) with face centred cubic structure. Fourier-transform infrared spectroscopy (FTIR) confirms the capping of the active ingredients of seed extract and further the average size of 34 nm was confirmed by high-resolution transmission electron microscopy (HR-TEM) and energy dispersive X-ray analysis (EDX) confirms the purity of Bc-AgNPs. Due to the capping of the active ingredients of seed extract, the Bc-AgNPs have shown significant antibacterial activity against Gram negative bacteria and at the lower concentration of 100 µg*ml−1 it has 89% scavenging activity against free radicals. A strong anti-inflammatory (membrane stabilization) activity towards RBCs (98% at 100 µg*ml−1) was recorded when compared to the positive control (aceclofenac). In addition to the previous activities, a greater inhibition of carbohydrate hydrolyzing enzymes such as α-amylase, α-glucosidase and DPP-IV highlighted the antidiabetic potential of these green synthesized AgNPs. Overall, the efficient bioactivities of Bc-AgNPs advocates its future potential in biomedical products. [ABSTRACT FROM AUTHOR]

The present study investigated the possible influence of enzymatic browning of banana peel over the production of silver nanoparticles (AgNPs). Firstly, aqueous extracts of banana peel were prepared at different times after peeling and they were used as reducing and stabilizing agents for the production of AgNPs as monitored by visual inspection and spectrophotometry. Hydrodynamic diameters, polydispersity indexes, and Zeta potentials of the produced AgNPs were evaluated. Besides, antimicrobial activities of the AgNPs produced in the moment of peeling and after up to 2 h were assessed. As longer the period of time passed after peeling, AgNPs produced showed a tendency to decrease the size, to become with Zeta potential more negative, and to stabilize their polydispersity indexes. Antimicrobial assays showed that the two tested AgNPs were similarly effective against Escherichia coli and Staphylococcus aureus at 128 and 256 μM, respectively. This study demonstrated that banana peels extracts obtained after different times affected the production of AgNPs in different manners, producing AgNPs with distinct characteristics, such as hydrodynamic diameter, Zeta potential, and polydispersity index. Moreover, all tested AgNPs showed antimicrobial activity. [ABSTRACT FROM AUTHOR]

In this work, the feasibility of obtaining Alite and Belite with possible applications in the cement industry from the primary sludge generated by a paper recycling industry in the State of Santa Catarina, Brazil was studied. The effect of the heat treatment on the physical and chemical properties of the primary sludge was studied, when treated at 800 °C, 875 °C and 950 °C, and defined by studies using the dilatometry technique. The treated sludge at these temperatures was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), thermal dilatometry (TD), X-ray fluorescence spectroscopy (XRF), surface analysis by the method of Brunauer, Emmett, Teller (BET), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The results showed the appearance of the Alite and Belite phases with different proportions, depending on the temperatures used during the heat treatment processes and with sufficient quality for application in the cement industry, since the optimal condition to obtain Alite is the heat treatment at 950 °C. In addition, the temperatures used were lower than those used in the conventional processes of Alite and Belite. [ABSTRACT FROM AUTHOR]

A silicon/polyaniline/horseradish peroxidase enzyme (n-Si/PANI/HRP) electrode was obtained by potentiostatic electrodeposition processes. PANI thin films were electropolymerized on a silicon substrate at different electric potentials, and an HRP enzyme was electrodeposited on the best PANI thin film. The best PANI thin film was obtained under electrodeposition conditions of + 1.00 V (vs. Ag/AgCl) and 900 s, and the immobilization of the HRP enzyme was performed at an electric potential of − 0.50 V (vs. Ag/AgCl). The n-Si/PANI- and n-Si/PANI/HRP electrodes were characterized using scanning electron microscopy and atomic force microscopy. The detection capacity of the glyphosate of the n-Si/PANI/HRP electrode with the best morphological characteristics was evaluated according to the electric current density responses from the oxidation of hydroquinone molecules in a solution containing different concentrations of glyphosate. The detection was performed because of the inhibition of the HRP enzyme activity by the glyphosate molecules in the solutions with a lower concentration limit of 5.44 μg L−1 over an electric potential range of + 0.65 to + 1.15 V (vs. Ag/AgCl). [ABSTRACT FROM AUTHOR]

In this paper, we present a realistic use case in order to investigate the feasibility of a secondary service transmission over an existent satellite infrastructure. By introducing the overlay cognitive radio paradigm towards satellite communications, we compute a theoretical achievable data rate greater than 16 kbps for the secondary service, which is suitable for most M2M applications. Using simulation results, we show that this can be achieved while preserving the primary service performance. In addition, a system design framework is discussed in order to dimension such systems. [ABSTRACT FROM AUTHOR]

The study describes the microencapsulation of Pterodon emarginatus fruit essential oil (OE) by spray drying using Brazilian Cerrado cashew polysaccharide (PEJU, Anacardium othonianum Rizz.) and maltodextrin (M) as wall materials. The microcapsules presented particles with irregular and rough surfaces confirmed by X-ray diffraction, with 57% in dry diameters ranging from 0 to 1 μm. Thermogravimetry showed a thermostable encapsulating material (peaks at 301 °C and 429 °C), with no loss of the encapsulated core. Zeta potential (ζ = − 0.18 mV) demonstrated the material's amphiphilic power. The ratio of 1:3:3.6 of OE:cashew PEJU:M (w/w/w) showed the best encapsulation effect (75% yield and 6.25% of the OE retained) in the same proportion of β-caryophyllene retained. The Brazilian Cerrado cashew PEJU is a promising source for use as wall material in microcapsules, especially in protecting the OE of P. emarginatus fruits, as replacement for other gums, such as gum Arabic. [ABSTRACT FROM AUTHOR]

The goal of this paper was to synthesize and characterize core–shell iron-carbon nanoparticles. For this purpose, nanoparticles were synthetized via a hydrothermal co-precipitation route, applying a 22 factorial experimental design with a central point, and varying both the concentration of the iron precursor (iron nitrate) and the reaction temperature. The nanoparticles were characterized via the following analysis: vibrating sample magnometry (VSM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), high resolution field emission gun scanning electron microscopy (SEM/FEG) and transmission electron microscopy (TEM) analysis. The results showed that the hydrothermal co-precipitation synthesis route enabled the production of Fe3O4–Fe2O3@C core–shell nanoparticles with dimensions between 4 and 8 nm. An increase in iron nitrate concentration and temperature during synthesis entailed a decrease in the remnant field and the magnetization of the nanoparticles. [ABSTRACT FROM AUTHOR]

The main aim of this article is to identify how the pressures from the external environment, in relation to the adoption of practices for sustainability in the environmental dimension, interfere with the organizational routines of companies involved in the plastic transformation chain. This research used a qualitative method because we sought to understand the meaning of managerial decisions regarding the routines that make up an organizational structure. For this purpose, secondary sources of evidence were used, which provided information on the history, infrastructure and products of 107 companies associated with the Brazilian Association of the Plastic Industry (Abiplast). In addition, six individuals directly linked to the plastics industry were also interviewed in order to obtain more evidence about the changes in the routines of this industry. For the analysis of the data, the constant comparison method was used based on the coding technique to identify patterns of behavior. The qualitative data were analyzed using the Atlas.ti version 7 software. The results demonstrate that the routines can be categorized as isomorphic or evolutionary, which is the main contribution of this research. In addition, the type of routine adopted may be associated with the company being reactive or proactive in relation to the pressures from the external environment. Furthermore, we can also say that the activities involved in the creation of new routines for environment sustainability are linked to three actions: building an infrastructure for sustainability, managing a circular flow of resources and innovation for sustainability. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the potential of silver nanoparticle synthesis using extracts from the leaves of Pterodon emarginatus (white sucupira) collected during the summer and winter seasons. Leaves were collected for the production of aqueous extracts, which were added to the aqueous solutions of silver nitrate leading to a final concentration of 1 mM. The reactions were incubated at 75 °C for 150 min and monitored every 30 min by absorption spectroscopy at 425 nm. The samples were complementarily characterized by dynamic light scattering, zeta potential, transmission electron microscopy, atomic force microscopy, MALDI-TOF mass spectrometry, Fourier transform infrared spectroscopy and X-ray diffraction analyses. Both extracts (summer and winter) exhibited a satisfactory reduction of silver ions, capable of inducing the formation of AgNPPe with considerable colloidal stability. The seasons of leaf collection interfered with the synthesis and yield of the AgNPPe, and also with their hydrodynamic diameters and zeta potentials, but the particles showed similar dry sizes (height and diameter), molecular profiles, and crystallinity patterns of the atoms. In sum, the results indicated that some AgNPPe parameters can be tunable by seasonal aspects of the plants and, therefore, such nanomaterials are propitious aiming future evaluation of their applications in several areas. [ABSTRACT FROM AUTHOR]

The most commonly used solution in chrome plating bath is chromic acid (hexavalent Cr), and a considerable amount of mists is released into the air and consequently produce hazards to workers. Thus, the aim of this study was to evaluate whether the biomarker of exposure to metals, specially Cr levels, presents associations with hematological and biochemical parameters and if they can alter the activity of enzymes that contain thiol groups such as pyruvate kinase, creatine kinase, adenylate kinase, and δ-aminolevulinate dehydratase. Fifty male chrome plating workers were used for exposed group and 50 male non-exposed workers for control group. For that, biological monitoring was performed through quantification of metals on total blood and urine by inductively coupled plasma mass spectrometry (ICP-MS) and enzyme activity was performed by spectrometry in erythrocytes. In addition, chromium levels in water was quantified and ecotoxicology assay was performed with Allium cepa test. The results demonstrated that blood and urinary chromium levels in exposed group were higher than the control group (p < 0.0001). Furthermore, decreased activity of enzymes was found in those that contain thiol groups from exposed group when compared with the control group (p < 0.001). The water analysis did not present a statistical difference between control and exposed groups (p > 0.05), demonstrating that water did not seem to be the source of contamination. In summary, our findings indicated some toxicology effects observed in the exposed group, such as thiol enzyme inhibition, mainly associated with occupational exposure in chrome plating and besides the presence of other metals, and Cr demonstrated to influence the activity of the enzymes analyzed in this research. [ABSTRACT FROM AUTHOR]

This paper deals with the hierarchical control of the wave equation. We use Stackelberg-Nash strategies. As usual, we consider one leader and two followers. To each leader we associate a Nash equilibrium corresponding to a bi-objective optimal control problem; then, we look for a leader that solves an exact controllability problem. We consider linear and semilinear equations. [ABSTRACT FROM AUTHOR]

Tymovirus is a genus of plant pathogenic viruses that infects several dicotyledonous plants worldwide, causing serious diseases in economically important crops. The known cytopathic effect on the host cell organelles involves chloroplast membrane deformation and the induction of vesicles in its periphery. These vesicles are known to be the location where tymoviral genomic RNA replication occurs. Tomato blistering mosaic virus (ToBMV) is a tymovirus recently identified in tomato plants in Brazil, which is able to infect several other plants, including tobacco. In this work, we investigated the chloroplast proteomic profile of ToBMV-infected N. benthamiana using bidimensional electrophoresis (2-DE) and mass spectrometry, aiming to study the virus-host interaction related to the virus replication and infection. A total of approximately 200 spots were resolved, out of which 36 were differentially abundant. Differential spots were identified by mass spectrometry including photosynthesis-related and defense proteins. We identified proteins that may be targets of a direct interaction with viral proteins, such as ATP synthase β subunit, RNA polymerase beta-subunit, 50S ribosomal protein L6 and Trigger factor-like protein. The identification of these candidate proteins gives support for future protein-protein interaction studies to confirm their roles in virus replication and disease development. [ABSTRACT FROM AUTHOR]

Byrsonima, especially the species Byrsonima intermedia, is an endangered Brazilian plant that has been widely used as food and for its therapeutic characteristics. However, this species faces challenges with sexual propagation, and somatic embryogenesis has emerged as a viable alternative option for propagation. Therefore, this study aimed to establish a protocol for inducing somatic embryogenesis in B. intermedia. For the induction of callus from in vitro seedling leaves, different subcultures (three subcultures, 60 days each) and concentrations of different cytokinins (BAP, TDZ, Kin and ZEA) combined with varying NAA solutions were tested. Different concentrations of NAA were also analyzed in the induction of pro-embryogenic calli. For the induction of embryogenic calli and somatic embryos, the pro-embryogenic calli were subcultured on MS medium without adding growth regulators. The somatic embryos that originated were inoculated on a maturation medium containing different concentrations of gibberellic acid (GA3). The formation of secondary embryos was also analyzed using different concentrations (0, 2.88, and 8.66 µM) of GA3 and different types of lids (Conventional lid, Biossama® commercial lid and conventional lid with membranes). The results show that for the induction of somatic embryos, the use of kinetin with NAA presented the formation of somatic embryos in the second (4.76 µM CIN + 0.54 µM NAA) and third (5.17 µM CIN + 10.54 µM NAA) subcultures. The use of 28.87 µM GA3 favored the formation of seedlings. The Biossama lid and 2.88 µM GA3 showed higher formation of secondary embryos. [ABSTRACT FROM AUTHOR]

The Sinos River is an important water supply in Southern Brazil and receives industrial, agricultural, and domestic effluents which may affect aquatic biota. Water physicochemical and microbiological analyses, biomarker responses (scaled mass index (SMI), gill histopathology, and micronucleus and nuclear abnormality (MN and NA) frequencies), and metal bioaccumulation in muscle were assessed in the fish species Bryconamericus iheringii (Characidae) captured at three sampling sites (S1, S2, and S3) in four sampling periods. The mean values of five parameters (total phosphorus, thermotolerant coliforms, aluminum, iron, and lead) exceeded the limits established by the Brazilian legislation at the three sampling sites. Although physicochemical analysis indicated higher impacts at S3, in some samples, significantly higher MN frequencies and bioaccumulation of manganese in fish muscle were observed at S1, whereas low SMI and higher concentrations of aluminum and zinc in fish muscle were found at S2. Histopathological alterations in gills were observed in fish collected at the three sampling sites; however, no spatial differences were observed, indicating similar environmental conditions with respect to this biomarker. Moreover, temporal variation of biomarker responses and metal bioaccumulation were found at all sampling sites. Furthermore, the consumption of fish from the Sinos River should be avoided given the concentrations of chromium (all samples), cadmium, and lead in fish muscle above the threshold for safe human consumption. [ABSTRACT FROM AUTHOR]

Passiflora ligularis Juss. is an endemic species from South America with important medicinal and economical properties. The development of improved micropropagation techniques is necessary to provide rapid and efficient clonal propagation of elite genotypes with high resistance and uniform production, as well as a system that can be used for genetic transformation. For this reason, we focused on establishing a protocol for somatic embryogenesis in P. ligularis from mature zygotic embryos. Our results demonstrate that the highest frequencies of somatic embryo formation was observed on a culture medium supplemented with 27.2 µM 2,4-diclorophenoxyacetic acid plus 4.5 µM 6-benzyladenine. Histological analyses of somatic embryogenesis were performed every 7 days after induction over 60 days of exposure to the medium. We present clear evidence for the precise origin of de-differentiation. Initial cell divisions occurred from a group of cells (multicellular origin) on the abaxial surface of the cotyledon in the periphery of the epidermal tissues of mature zygotic embryos after 14 days of incubation. After 21 days, internal segmenting divisions resulted in the embryogenic character of the tissue. Globular embryos contain a protoderm surrounding a mass of vacuolated parenchymatous cells and meristematic regions with an observable procambium zone after 45 days. The complete independence of somatic embryos from the adjacent tissues was histologically confirmed by the absence of vascular continuity between them, after 60 days. We describe for the first time the development of somatic embryos in P. ligularis and demonstrate that somatic embryos develop into plants that can later on be acclimatized. [ABSTRACT FROM AUTHOR]

Hancornia speciosa is a native fruit species from Brazil with important economic applications. However, the use of this species has been challenged by difficulties in its storage. Cryopreservation is a safe and efficient tool for long-term storage. Nevertheless, cryopreservation may promote reactive oxygen species (ROS) formation with subsequent lipid peroxidation, which causes membrane damage. The use of in vitro antioxidant compounds could help eliminate ROS and consequently improve explant survival. In the current study, the lateral buds of H. speciosa were precultivated in proline or glycine betaine (GB)-containing solutions, and the effect of these compounds on the enzymatic activity of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) and on lipid peroxidation was measured after sample warming. The present findings indicated that oxidative stress induced by cryopreservation was significantly reduced by the precultivation of lateral buds with proline and GB. SOD activity increased, and subsequently, hydrogen peroxide (HO) production increased followed by the immediate activation of CAT and APX. The enzyme activity increased for 7 following rewarming, indicating that precultivation with 0.1 M proline was fundamental to achieving high levels of shoot regeneration from H. speciosa lateral buds. [ABSTRACT FROM AUTHOR]

The Sinos River is one of the most polluted rivers in Brazil. The purpose of this work was to monitor the presence of some pesticides and hydrocarbons as well as the genotoxic and cytotoxic potential on HEp-2 cells from water samples collected at seven sites in the Sinos River Basin (SRB), southern Brazil. Nine samples were taken from the three main rivers in the SRB and used as a solution to dilute the HEp-2 cell culture medium after microfiltration. Twenty-four pesticides and 19 hydrocarbons were measured. Cytotoxicity was assessed by methyl thiazolyl tetrazolium (MTT) and neutral red (NR) assays, in which cells were exposed to different concentrations of the water samples for 24 h. Genotoxicity of the microfiltrated raw water samples was assessed by comet assay after 6 and 24 h of exposure. Among the chemicals analyzed, only the 2,4-D, dichloromethane, tetrachloroethene, chloroform, bromodichloromethane, styrene, and toluene were detected, but they were all lower than the limit established by Brazilian regulations. Twenty samples from a total of 60 had a cytotoxic effect in the MTT assay and 30 in the NR assay. The comet assay indicated the presence of genotoxic substances in the water at the seven locations monitored. Temporal and spatial variation was observed in the cytotoxicity and genotoxicity assays. Results indicated that the water in all stretches of the SRB is contaminated and it can cause harmful effects to humans and to the aquatic biota. This HEp-2 cell-line approach can be an additional tool for environmental monitoring. [ABSTRACT FROM AUTHOR]

Gallium-arsenide (GaAs) and helium-neon (HeNe) lasers are the most commonly used low-energy lasers in physiotherapy for promoting wound healing and pain modulation. The aim of this study was investigate the effect of low-power laser irradiation (LPLI) at different wavelengths and doses on oxidative stress and fibrogenesis parameters in an animal model of wound healing. The animals were randomly divided into five groups (n=6): Controls (skin injured animals without local or systemic treatment), skin injury treated with HeNe 1 J/cm(2) (two seg); skin injury treated with HeNe 3 J/cm(2) (six seg); skin injury treated with GaAs 1 J/cm(2) (three seg); skin injury treated with GaAs 3 J/cm(2) (nine seg). A single circular wound measuring 8 mm in diameter was surgically created on the back of the animal. The rats were irradiated at 2, 12, 24, 48, 72, 96, and 120 h after skin injury. The parameters, namely hydroxyproline content, activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), and lipid (TBARS) and protein oxidation (carbonyl groups) measurements were assessed. In addition, wound size regression was also analyzed. The results showed an improvement in the wound healing reflected by the reduction in wound size and increased collagen synthesis. Moreover, a significant reduction in TBARS levels, carbonyl content, and SOD and CAT activities were observed after laser irradiation, particularly with the treatments HeNe laser 1 and 3 J/cm(2) dose and GaAs 3 J/cm(2) dose. The data strongly indicate that LPLI therapy is efficient in accelerating the skin wound healing process after wounding, probably by reducing the inflammatory phase and inducing collagen synthesis. [ABSTRACT FROM AUTHOR]

Age-associated decline in skeletal muscle mass and strength is associated with oxidative stress and Ca homeostasis disturbance. Exercise should be considered a viable modality to combat aging of skeletal muscle. This study aimed to investigate whether continuous and fractionated training could be useful tools to attenuate oxidative damage and retain calcium-handling proteins. We conducted the study using 24-month-old male Wistar rats, divided into control, continuous, and fractionated groups. Animals ran at 13 m min for five consecutive days (except weekends) for 6 weeks, for a total period of 42 days. Each session comprised 45 min of exercise, either continuous or divided into three daily sessions of 15 min each. Metabolic and oxidative stress markers, protein levels of mitochondrial transcription factors, and calcium-handling proteins were analyzed. Continuous exercise resulted in reduced ROS production as well as showed a decrease in TBARS levels and carbonyl content. On the other hand, fractionated training increased the antioxidant enzyme activities. The ryanodine receptor and phospholamban protein were regulated by continuous training while sodium calcium exchange protein was increased by the fractionated training. These data suggest that intracellular Ca can be modulated by various training stimuli. In addition, the modulation of oxidative stress by continuous and fractionated training may play an important regulatory role in the muscular contraction mechanism of aged rats, due to changes in calcium metabolism. [ABSTRACT FROM AUTHOR]