Search results for: Renato P. Da Cunha

Authors: Francisco José Plácido da Cunha, Tassio Ferenzini Martins Sirqueira, Marx Leles Viana, Carlos José Pereira de Lucena

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Open Multiagent Systems (MASs) are societies in which heterogeneous and independently designed entities (agents) work towards similar, or different ends. Software agents are autonomous and the diversity of interests among different members living in the same society is a fact. In order to deal with this autonomy, these open systems use mechanisms of social control (norms) to ensure a desirable social order. This paper considers the following types of norms: (i) obligation — agents must accomplish a specific outcome; (ii) permission — agents may act in a particular way, and (iii) prohibition — agents must not act in a specific way. All of these characteristics mean to encourage the fulfillment of norms through rewards and to discourage norm violation by pointing out the punishments. Once the software agent decides that its priority is the satisfaction of its own desires and goals, each agent must evaluate the effects associated to the fulfillment of one or more norms before choosing which one should be fulfilled. The same applies when agents decide to violate a norm. This paper also introduces a framework for the development of MASs that provide support mechanisms to the agent’s decision-making, using norm-based reasoning. The applicability and validation of this approach is demonstrated applying a traffic intersection scenario.

Keywords: BDI agent, BDI4JADE framework, multiagent systems, normative agents

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Authors: Bruno D. Souza, Gerson G. Cunha, Michael O. Ferreira, Roberto Rosenhaim, Robson C. Santos, Sergio O. Santos

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Devices and applications that use satellite-based positioning are becoming more popular day-by-day. Thus, evolution and improvement in this technology are mandatory. Accordingly, satellite georeferenced systems need to accomplish the same evolution rhythm. Either GPS (Global Positioning System) or its similar Russian GLONASS (Global Navigation Satellite System) are system samples that offer us powerful tools to plot coordinates on the earth surface. The development of this research aims the study of several aspects related to use of GPS and GLONASS technologies, given its application and collected data improvement during geodetic data acquisition. So, both relevant theoretic and practical aspects are considered. In this context, at the theoretical part, the main systems' characteristics are shown, observing its similarities and differences. At the practical part, a series of experiences are performed and obtained data packages are compared in order to demonstrate equivalence or differences among them. The evaluation methodology targets both quantitative and qualitative analysis provided by GPS and GPS/GLONASS receptors. Meanwhile, a specific collected data storage system was developed to better compare and analyze them (SisGeo - Georeferenced Research Comparison Support System).

Keywords: satellites, systems, applications, experiments, receivers

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Authors: Gizelle K. Vianna, Gabriel V. Cunha, Gustavo S. Oliveira

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Foliage diseases in plants can cause a reduction in both quality and quantity of agricultural production. Intelligent detection of plant diseases is an essential research topic as it may help monitoring large fields of crops by automatically detecting the symptoms of foliage diseases. This work investigates ways to recognize the late blight disease from the analysis of tomato digital images, collected directly from the field. A pair of multilayer perceptron neural network analyzes the digital images, using data from both RGB and HSL color models, and classifies each image pixel. One neural network is responsible for the identification of healthy regions of the tomato leaf, while the other identifies the injured regions. The outputs of both networks are combined to generate the final classification of each pixel from the image and the pixel classes are used to repaint the original tomato images by using a color representation that highlights the injuries on the plant. The new images will have only green, red or black pixels, if they came from healthy or injured portions of the leaf, or from the background of the image, respectively. The system presented an accuracy of 97% in detection and estimation of the level of damage on the tomato leaves caused by late blight.

Keywords: artificial neural networks, digital image processing, pattern recognition, phytosanitary

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Authors: Arianne V. Julian, Michael R. Umagat, Renato G. Reyes

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Pleurotus ostreatus, which is one of the most widely cultivated mushrooms, is an excellent source of protein and other minerals but inherently contains low calcium level. Calcium plays several vital functions in human health; therefore, adequate daily intake is necessary. Supplementation of growth substrate is a significant approach in mushroom production to improve nutritional content and yield. This study focused on the influence of varying concentrations of Ca supplementation derived from natural sources including agricultural lime, eggshell and oyster shell in rice straw-based formulation for the production of P. ostreatus. The effect of Ca supplementation on the total yield and Ca content were obtained. Results revealed that these natural sources increased both the yield and Ca of P. ostreatus. Mushroom grown in substrate with 8-10% agricultural lime and 6% eggshell powder produced the highest yields while using oyster shell powder did not vary with the control. Meanwhile, substrate supplementation using agricultural lime and eggshell powder in all concentrations have increased Ca in fruiting bodies. However, Ca was not absorbed in the oyster shell powder-supplemented substrate. These findings imply the potential of agricultural lime and eggshell powder in the production of Ca-enriched mushrooms resulting in higher yield.

Keywords: calcium fortification, mushroom production, natural sources, Pleurotus ostreatus

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Authors: Edmar N. Franquera, Renato C. Mabesa, Rene Rafael C. Espino, Edralina P. Serrano, Eduardo P. Paningbatan Jr.

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The potential of growing lettuce with different colored plastic mulch silver (control), red, orange, yellow and green was evaluated using two lettuce varieties, Looseleaf and Romaine. The experiment was laid out on split plot design following the Randomized Complete Block Design. The Looseleaf variety had better performance in terms of plant fresh weight, leaf fresh weight, leaf dry weight, root length, plant height and yield. However, better response was observed in Romaine in terms of leaf diameter, leaf length, root dry weight and root fresh weight. The color of the mulch reflected different qualities of light and hence the quality of absorbed light by the lettuce plants. A higher Far red and red ratio (FR:R) was obtained from green plastic mulch which was followed by the red plastic mulch. The different colored plastic mulch affected the growth and developmental responses of leaf lettuce morphological and leaf anatomical characteristics. Data in all growth morphological and yield parameters showed that those grown with red plastic mulch had better response and had longer stomates than those lettuce grown with the other colored plastic mulch. The soil temperature 10 cm below the plastic mulch was significantly influenced by the color of the mulch. The red plastic mulch had the highest soil temperature recorded while the lowest soil temperature recorded was within the yellow plastic mulch.

Keywords: anatomical, lettuce, morpholological, plastic mulch

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Authors: Renato André S. Silva, Nana L. F. Sampaio, Carlos J. G. Cruz, Bruno Vianna, Flávio O. Pires

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multiple stage bicycle races require high physiological loads from professional cyclists. Such demands can lead to immunosuppression and health problems. However, in this type of competition, little is known about its physiological effects on amateur athletes, who generally receive less medical support. Thus, this study analyzes the hematological effects of a multiple stage bicycle race on amateur cyclists. Seven Brazilian national amateur cyclists (34 ± 4.21 years) underwent a laboratory test to evaluate VO2Max (69.89 ± 7.43 ml⋅kg-1⋅min-1). Six days later, these volunteers raced in the Tour of Goiás, participating in five races in four days (435 km) of competition. Arterial blood samples were collected one day before and one day after the competition. The Kolmogorov-Smirnov tests were used to evaluate the data distribution and Wilcoxon to compare the two moments (p <0.05) of data collection. The results show: Red cells ↓ 7.8% (5.1 ± 0.28 vs 4.7 ± 0.37 106 / mm 3, p = 0.01); Hemoglobin ↓ 7.9% (15.1 ± 0.31 vs 13.9 ± 0.27 g / dL, p = 0.01); Leukocytes ↑ 9.5% (4946 ± 553 versus 5416 ± 1075 / mm 3, p = 0.17); Platelets ↓ 7.0% (200.2 ± 51.5 vs 186.1 ± 39.5 / mm 3, p = 0.01); LDH ↑ 11% (164.4 ± 28.5 vs 182.5 ± 20.5 U / L, p = 0.17); CK ↑ 13.5% (290.7 ± 206.1 vs 330.1 ± 90.5 U / L, p = 0.39); CK-MB ↑ 2% (15.7 ± 3.9 vs. 20.1 ± 2.9 U / L, p = 0.06); Cortizol ↓ 13.5% (12.1 ± 2.4 vs 9.9 ± 1.9 μg / dL, p = 0.01); Total testosterone ↓ 7% (453.6 ± 120.1 vs 421.7 ± 74.3 ng / dL, p = 0.12); IGF-1 ↓ 15.1% (213.8 ± 18.8 vs 181.5 ± 34.7 ng / mL, p = 0.04). This means that there was significant reductions in O2 allocation / transport capacities, vascular injury disruption, and a fortuitous reduction of muscle skeletal anabolism along with maintenance and / or slight elevation of immune function, glucose and lipid energy and myocardial damage. Therefore, the results suggest that no abnormal health effect was identified among the athletes after participating in the Tour de Goiás.

Keywords: cycling, health effects, cycling stages races, haematology

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Authors: Rejane Maria P. da Silva, Mariana X. Milagre, João Victor de S. Araujo, Leandro A. de Oliveira, Renato A. Antunes, Isolda Costa

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The Al-Cu-Li alloys are advanced materials for aerospace application because of their interesting mechanical properties and low density when compared with conventional Al-alloys. However, Al-Cu-Li alloys are susceptible to localized corrosion. The near-surface deformed layer (NSDL) induced by the rolling process during the production of the alloy and its removal by polishing can influence on the corrosion susceptibility of these alloys. In this work, the influence of surface preparation effects on the electrochemical activity of AA2098-T351 (Al–Cu–Li alloy) was investigated using a correlation between surface chemistry, microstructure, and electrochemical activity. Two conditions were investigated, polished and as-received surfaces of the alloy. The morphology of the two types of surfaces was investigated using confocal laser scanning microscopy (CLSM) and optical microscopy. The surface chemistry was analyzed by X-ray Photoelectron Spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS). Global electrochemical techniques (potentiodynamic polarization and EIS technique) and a local electrochemical technique (Localized Electrochemical Impedance Spectroscopy-LEIS) were used to examine the electrochemical activity of the surfaces. The results obtained in this study showed that in the as-received surface, the near-surface deformed layer (NSDL), which is composed of Mg-rich bands, influenced the electrochemical behavior of the alloy. The results showed higher electrochemical activity to the polished surface condition compared to the as-received one.

Keywords: Al-Cu-Li alloys, surface preparation effects, electrochemical techniques, localized corrosion

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Authors: Robson da C. Santos, Carlos Henrique de A. S. P. Coutinho, Lucas Moreira Dias, Gerson Gomes Cunha

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The article refers to the development of an augmented reality 3D display, through the control of servo motors and projection of image with aid of video projector on the model. Augmented Reality is a branch that explores multiple approaches to increase real-world view by viewing additional information along with the real scene. The article presents the broad use of electrical, electronic, mechanical and industrial automation for geospatial visualizations, applications in mathematical models with the visualization of functions and 3D surface graphics and volumetric rendering that are currently seen in 2D layers. Application as a 3D display for representation and visualization of Digital Terrain Model (DTM) and Digital Surface Models (DSM), where it can be applied in the identification of canyons in the marine area of the Campos Basin, Rio de Janeiro, Brazil. The same can execute visualization of regions subject to landslides, as in Serra do Mar - Agra dos Reis and Serranas cities both in the State of Rio de Janeiro. From the foregoing, loss of human life and leakage of oil from pipelines buried in these regions may be anticipated in advance. The physical design consists of a table consisting of a 9 x 16 matrix of servo motors, totalizing 144 servos, a mesh is used on the servo motors for visualization of the models projected by a retro projector. Each model for by an image pre-processing, is sent to a server to be converted and viewed from a software developed in C # Programming Language.

Keywords: visualization, 3D models, servo motors, C# programming language

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Authors: Andressa S. T. Gomes, Luiza A. Souza, Luciana H. Yamane, Renato R. Siman

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The segregation of waste of electrical and electronic equipment (WEEE) in the generating source, its characterization (quali-quantitative) and identification of origin, besides being integral parts of classification reports, are crucial steps to the success of its integrated management. The aim of this paper was to count WEEE generation at the Federal University of Espírito Santo (UFES), Brazil, as well as to define sources, temporary storage sites, main transportations routes and destinations, the most generated WEEE and its recycling potential. Quantification of WEEE generated at the University in the years between 2010 and 2015 was performed using data analysis provided by UFES’s sector of assets management. EEE and WEEE flow in the campuses information were obtained through questionnaires applied to the University workers. It was recorded 6028 WEEEs units of data processing equipment disposed by the university between 2010 and 2015. Among these waste, the most generated were CRT screens, desktops, keyboards and printers. Furthermore, it was observed that these WEEEs are temporarily stored in inappropriate places at the University campuses. In general, these WEEE units are donated to NGOs of the city, or sold through auctions (2010 and 2013). As for recycling potential, from the primary processing and further sale of printed circuit boards (PCB) from the computers, the amount collected could reach U$ 27,839.23. The results highlight the importance of a WEEE management policy at the University.

Keywords: solid waste, waste of electrical and electronic equipment, waste management, institutional solid waste generation

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Authors: Claire B. Salvedia, Enrico P. Supangco, Francisco B. Eligado, Renato Sa Vega, Antonio A. Rayos

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The study was conducted to evaluate the effect of probiotic feeding on weight gain, blood biochemical and hematological indices of crossbred dairy goat kids. Sixteen (16) crossbred Anglo-Nubian x Saanen dairy goat kids, 3 to 4 months old, ranging from 19 to 23kg were randomly assigned into four treatments fed with 5x109 cfu/ml probiotic supplements; Treatment 1 – control; Treatment 2 – lactic acid bacteria (L. plantarum BS and P. acidilactici 3G3); treatment 3 – S. cerevisiae 2030; Treatment 4 – multi-strain probiotics (L. plantarum BS, P. acidilactici 3G3, and S.cerevisiae 2030). Feed ration provided daily for each of the experimental animals were composed of 1kg mixed concentrate feed ((Leucaena leucocephala dried leaves and pollard), and 4 kg fresh Pennisetum purpureum and Gliciridia sepium leaves (50:50). The experimental feeding trial lasted for 9 weeks. Result revealed that treatments fed with probiotics had significantly (P≤0.05) higher weight gain compared to the control. Significant effect on plasma urea nitrogen (PUN) and triglyceride were noted during 30th and 60th day of probiotic feeding. White blood cell counts were significantly affected by probiotic feeding during the 60th day. Concentrations of glucose and cholesterol remained unchanged throughout the experimental period. The findings suggests, under the condition of the experiment, that live probiotic feeding could have a significant role in improving weight gain and metabolism of crossbred dairy goat kids.

Keywords: probiotics, weight gain, blood biochemical indices, crossbred dairy goat kids

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Authors: Luciana C. Ramos, Leandro J. Sousa, Antônio Ferreira da Silva, Valéria Gomes Oliveira Falcão, Suzana T. Cunha Lima

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The commercial production of biodiesel using microalgae demands a high-energy input for harvesting biomass, making production economically unfeasible. Methods currently used involve mechanical, chemical, and biological procedures. In this work, a flocculation system is presented as a cost and energy effective process to increase biomass production of Phaeodactylum tricornutum. This diatom is the only species of the genus that present fast growth and lipid accumulation ability that are of great interest for biofuel production. The algae, selected from the Bank of Microalgae, Institute of Biology, Federal University of Bahia (Brazil), have been bred in tubular reactor with photoperiod of 12 h (clear/dark), providing luminance of about 35 μmol photons m^-2s^-1, and temperature of 22 °C. The medium used for growing cells was the Conway medium, with addition of silica. The seaweed growth curve was accompanied by cell count in Neubauer camera and by optical density in spectrophotometer, at 680 nm. The precipitation occurred at the end of the stationary phase of growth, 21 days after inoculation, using two methods: centrifugation at 5000 rpm for 5 min, and electro-flocculation at 19 EPD and 95 W. After precipitation, cells were frozen at -20 °C and, subsequently, lyophilized. Biomass obtained by electro-flocculation was approximately four times greater than the one achieved by centrifugation. The benefits of this method are that no addition of chemical flocculants is necessary and similar cultivation conditions can be used for the biodiesel production and pharmacological purposes. The results may contribute to improve biodiesel production costs using marine microalgae.

Keywords: biomass, diatom, flocculation, microalgae

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Authors: Renato Roda

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With the emergence of the so-called 'Knowledge Society', the implementation of policies to attract, grow and retain talents, in an academic context as well, has become critical –both in the perspective of didactics and research and as far as administration and institutional management are concerned. At the same time, the contemporary philanthropic entities/organizations, which are evolving from traditional types of social support towards new styles of aid, envisaged to go beyond mere monetary donations, face the challenge of brand-new forms of complexity in supporting such specific dynamics of the global human capital market. In this sense, it becomes unavoidable for the philanthropic foundation, while carrying out their daily charitable tasks, to resort to innovative ways to facilitate the acquisition and the promotion of talents by academic and research institutions. In order to deepen such a specific perspective, this paper features the case of Turin, former 'factory city' of Italy’s North West, headquarters -and main reference territory- of Italy’s largest and richest private formerly bank-based philanthropic foundation, the Fondazione Compagnia di San Paolo. While it was assessed and classified as 'medium' in the city Global Talent Competitiveness Index (GTCI) of 2020, Turin has nevertheless acquired over the past months status of impact laboratory for a whole series of innovation strategies in the competition for the acquisition of excellence human capital. Leading actors of this new city vision are the foundations with their specifically adjusted financial engagement and a consistent role of stimulus towards innovation for research and education institutions.

Keywords: human capital, post-Fordism, private foundation, war on talents

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Authors: Sandrieli Afornali, Adriano Keijiro Maeda, Renato Fedatto Beraldo, Carlos Alberto Mattozo, Ricardo Nascimento Brito

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BACKGROUND: The most used variety in hydrocephalus treatment is the ventriculoperitoneal shunt (VPS). However, it may fails in 20 to 70% of cases. It makes necessary to have alternative cavities for the implantation of the distal catheter. Ventriculo-atrial shunting (VAS) is described as the second option. To our knowledge, there are 121 reported cases of VGB shunt in children until 2020 and a highly variable success rate, from 25 to 100%, with an average of 63% of patients presenting good long-term results. Our goal is to evaluate the epidemiological profile of patients submitted to ventriculo-gallbladder (VGB) shunt and, through a review of literature, to compare our results with others series. METHODS: a retrospective cross-sectional observational study of a case series of nine patients. The medical records of all patients were reviewed, who underwent VGB shunt at the Hospital Pequeno Príncipe from Curitiba, Paraná, Brazil, from January 2014 to October 2022. The inclusion criteria were: patients under 17 years of age with hydrocephalus of any etiology, currently using or prior to VGB shunt. RESULTS: There were 6 (66,7%) male and 3 (33,3%) female. The average age of 73.6 months or 6.1 years at the time of surgery. They were submitted on average 5.1 VPS reviews previous to VGB shunt. Five (55,5%) had complications of VGB shunt: infection (11.1%), atony (11.1%), hypodrainage due to kinking the distal catheter in the solution (11.1%) and ventriculoenteric fistula (22.2%); all these patients were cured at surgical reapproach, and in 2 of them the VGB shunt was reimplanted. Two patients died (22.2%), and five (55,5%) patients maintained the use of VGB shunt in the follow-up period; and in 4 (44.4%) there was never need for review. CONCLUSION: VGB shunt tends to be underestimated because it is still unconventional and little publicized in literature. Our article shows a lower risk of death and similar risk of complications when compared to others altenatives shunts. We emphasize VGB shunt as a safe procedure to be the second option when VPS fails or has contraindications.

Keywords: hydrocephalus, ventricular-gallbladder shunt, VGB shunt, VPS, ventriculoperitoneal shunt, ventriculoatrial shunt

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Authors: Antonio Horta, Renato Marinho, Raimir Holanda

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Considered as an evolution of the Blockchain, the Ethereum platform, besides allowing transactions of its cryptocurrency named Ether, it allows the programming of decentralised applications (DApps) and smart contracts. However, this functionality into blockchains has raised other types of threats, and the exploitation of smart contracts vulnerabilities has taken companies to experience big losses. This research intends to figure out the number of contracts that are under risk of being drained. Through a deep investigation, more than two hundred thousand smart contracts currently available in the Ethereum platform were scanned and estimated how much money is at risk. The experiment was based in a query run on Google Big Query in July 2022 and returned 50,707,133 contracts published on the Ethereum platform. After applying the filtering criteria, the experimentgot 430,584 smart contracts to download and analyse. The filtering criteria consisted of filtering out: ERC20 and ERC721 contracts, contracts without transactions, and contracts without balance. From this amount of 430,584 smart contracts selected, only 268,103 had source codes published on Etherscan, however, we discovered, using a hashing process, that there were contracts duplication. Removing the duplicated contracts, the process ended up with 20,417 source codes, which were analysed using the open source SAST tool smartbugswith oyente and securify algorithms. In the end, there was nearly $100,000 at risk of being drained from the potentially vulnerable smart contracts. It is important to note that the tools used in this study may generate false positives, which may interfere with the number of vulnerable contracts. To address this point, our next step in this research is to develop an application to test the contract in a parallel environment to verify the vulnerability. Finally, this study aims to alert users and companies about the risk on not properly creating and analysing their smart contracts before publishing them into the platform. As any other application, smart contracts are at risk of having vulnerabilities which, in this case, may result in direct financial losses.

Keywords: blockchain, reentrancy, static application security testing, smart contracts

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Authors: Maria C. Proença, Maria T. Rebelo, Marília Antunes, Maria J. Alves, Hugo Osório, Sofia Cunha, João Casaca

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Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens sl. mosquitoes collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters such as: air relative humidity, air temperature (minima, maxima and mean daily temperatures), daily total rainfall, altitude, land use/land cover and proximity to water bodies are evaluated. Focus is on the mosquito females; the characterization of its habitat is the key for the planning of chirurgical non-aggressive prophylactic countermeasures to avoid ambient degradation. The GIS allow for the spatial determination of the zones were the mosquito mean captures has been above average; using the meteorological values at these coordinates, the limits of each parameter are identified/computed. The meteorological parameters measured at the net of weather stations all over the country are averaged by month and interpolated to produce raster maps that can be segmented according to the thresholds obtained for each parameter. The intersection of the maps obtained for each month show the evolution of the area favorable to the species through the mosquito season, which is from May to October at these latitudes. In parallel, mean and above average captures were related to the physiographic parameters. Three levels of risk could be identified for each parameter, using above average captures as an index. The results were applied to the suitability meteorological maps of each month. The Culex pipiens critical niche is delimited, reflecting the critical areas and the level of risk for transmission of the pathogens to which they are competent vectors (West Nile virus, iridoviruses, rheoviruses and parvoviruses).

Keywords: Culex pipiens, ecological niche, risk assessment, risk management

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Authors: Maria C. Proença, Maria T. Rebelo, Maria J. Alves, Sofia Cunha

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Vector-borne diseases are transmitted to humans by mosquitos, sandflies, bugs, ticks, and other vectors. Some are re-transmitted between vectors, if the infected human has a new contact when his levels of infection are high. The vector is infected for lifetime and can transmit infectious diseases not only between humans but also from animals to humans. Some vector borne diseases are very disabling and globally account for more than one million deaths worldwide. The mosquitoes from the complex Culex pipiens sl. are the most abundant in Portugal, and we dispose in this moment of a data set from the surveillance program that has been carried on since 2006 across the country. All mosquitos’ species are included, but the large coverage of Culex pipiens sl. and its importance for public health make this vector an interesting candidate to assess risk of disease amplification. This work focus on ports and airports identified as key areas of high density of vectors. Mosquitoes being ectothermic organisms, the main factor for vector survival and pathogen development is temperature. Minima and maxima local air temperatures for each area of interest are averaged by month from data gathered on a daily basis at the national network of meteorological stations, and interpolated in a geographic information system (GIS). The range of temperatures ideal for several pathogens are known and this work shows how to use it with the meteorological data in each port and airport facility, to focus an efficient implementation of countermeasures and reduce simultaneously risk transmission and mitigation costs. The results show an increased alert with decreasing latitude, which corresponds to higher minimum and maximum temperatures and a lower amplitude range of the daily temperature.

Keywords: human health, risk assessment, risk management, vector-borne diseases

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Authors: Byl Farney Cunha Junior

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In this work the dynamic three-dimensional analysis of a 47-story building located in Goiania city when subjected to wind loads generated using both the Wind Brazilian code, NBR6123 (ABNT, 1988) and the Synthetic-Wind method is realized. To model the frames three different methodologies are used: the shear building model and both bi and three-dimensional finite element models. To start the analysis, a plane frame is initially studied to validate the shear building model and, in order to compare the results of natural frequencies and displacements at the top of the structure the same plane frame was modeled using the finite element method through the SAP2000 V10 software. The same steps were applied to an idealized 20-story spacial frame that helps in the presentation of the stiffness correction process applied to columns. Based on these models the two methods used to generate the Wind loads are presented: a discrete model proposed in the Wind Brazilian code, NBR6123 (ABNT, 1988) and the Synthetic-Wind method. The method uses the Davenport spectrum which is divided into a variety of frequencies to generate the temporal series of loads. Finally, the 47- story building was analyzed using both the three-dimensional finite element method through the SAP2000 V10 software and the shear building model. The models were loaded with Wind load generated by the Wind code NBR6123 (ABNT, 1988) and by the Synthetic-Wind method considering different wind directions. The displacements and internal forces in columns and beams were compared and a comparative study considering a situation of a full elevated reservoir is realized. As can be observed the displacements obtained by the SAP2000 V10 model are greater when loaded with NBR6123 (ABNT, 1988) wind load related to the permanent phase of the structure’s response.

Keywords: finite element method, synthetic wind, tall buildings, shear building

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Authors: C. F. Alegretti, F. R. Cunha, R. G. Gontijo

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This work investigates the effects of an applied magnetic field on the geometry-driven boundary layer detachment flow of a ferrofluid over a sudden expansion. Both constitutive equation and global magnetization equation for a ferrofluid are considered. Therefore, the proposed formulation consists in a coupled magnetic-hydrodynamic problem. Computational simulations are carried out in order to explore, not only the viability to control flow instabilities, but also to evaluate the consistency of theoretical aspects. The unidirectional sudden expansion in a ferrofluid flow is investigated numerically under the perspective of Ferrohydrodynamics in a two-dimensional domain using a Finite Differences Method. The boundary layer detachment induced by the sudden expansion results in a recirculating zone, which has been extensively studied in non-magnetic hydrodynamic problems for a wide range of Reynolds numbers. Similar investigations can be found in literature regarding the sudden expansion under the magnetohydrodynamics framework, but none considering a colloidal suspension of magnetic particles out of the superparamagnetic regime. The vorticity-stream function formulation is implemented and results in a clear coupling between the flow vorticity and its magnetization field. Our simulations indicate a systematic decay on the length of the recirculation zone as increasing physical parameters of the flow, such as the intensity of the applied field and the volume fraction of particles. The results all are discussed from a physical point of view in terms of the dynamical non-dimensional parameters. We argue that the decrease/reduction in the recirculation region of the flow is a direct consequence of the magnetic torque balancing the action of the torque produced by viscous and inertial forces of the flow. For the limit of small Reynolds and magnetic Reynolds parameters, the diffusion of vorticity balances the diffusion of the magnetic torque on the flow. These mechanics control the growth of the recirculation region.

Keywords: boundary layer detachment, ferrofluid, ferrohydrodynamics, magnetization, sudden expansion

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Authors: Maryvone Cunha de Morais, Lilian Cristine Hübner

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Based on a translanguaging theoretical approach, which considers language not as separate entities but as an entire repertoire available to bilingual individuals, this systematic review aimed at analyzing the methods (aims, samples investigated, type of stimuli, and analyses) adopted by studies on translanguaging practices associated with written and oral tasks (separately or integrated) in bilingual education. The PRISMA criteria for systematic reviews were adopted, with the descriptors "translanguaging", "bilingual education" and/or “written and oral tasks" to search in Pubmed/Medline, Lilacs, Eric, Scopus, PsycINFO, and Web of Science databases for articles published between 2017 and 2021. 280 registers were found, and after following the inclusion/exclusion criteria, 24 articles were considered for this analysis. The results showed that translanguaging practices were investigated on four studies focused on written production analyses, ten focused on oral production analysis, whereas ten studies focused on both written and oral production analyses. The majority of the studies followed a qualitative approach, while five studies have attempted to study translanguaging with quantitative statistical measures. Several types of methods were used to investigate translanguaging practices in written and oral production, with different approaches and tools indicating that the methods are still in development. Moreover, the findings showed that students’ interactions have received significant attention, and studies have been developed not just in language classes in bilingual education, but also including diverse educational and theoretical contexts such as Content and Language Integrated Learning, task repetition, Science classes, collaborative writing, storytelling, peer feedback, Speech Act theory and collective thinking, language ideologies, conversational analysis, and discourse analyses. The studies, whether focused either on writing or oral tasks or in both, have portrayed significant research and pedagogical implications, grounded on the view of integrated languages in bi-and multilinguals.

Keywords: bilingual education, oral production, translanguaging, written production

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Authors: Rossana Taravella, Gilberto M. Cellura, Giuseppe Cirrincione, Salvatore Asciutto, Marco Caruso, Massimo Benedetto, Renato Ciofalo, Giuliana Pace, Salvatore Novo

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Objectives: This retrospective analysis sought to evaluate 1-month outcomes and therapy effectiveness of a population of patients treated with MitraClip therapy. We describe in this article the preliminary results of primary effectiveness endpoint. Background: Percutaneous Mitral Repair is being developed to treat severe mitral regurgitation (MR), with increasing real-world cases of functional MR (FMR). In the EVEREST (Endovascular Valve Edge-to-Edge Repair Study)II trial, the percutaneous device showed superior safety but less reduction in MR at 1year. 4-year outcomes from EVEREST II trial showed no difference in the prevalence of moderate-severe and severe MR or mortality at 4years between surgical mitral repair and percutaneous approach. Methods: We analysed retrospectively collected data from one center experience in Italy enrolled from January 2011 to December 2016. The study included 62 patients [mean age 74±11years, 43 men (69%)] with MR of at least grade3+. Most of the patients had functional MR, were in New York Heart Association (NYHA) functional class III or IV, with a large portion (78%) of mild-to-moderate Tricuspid Regurgitation (TR). One or more clips were implanted in 67 procedures (62 patients). Results and Conclusions: Severity of MR was reduced in all successfully treated patients,54(90%) were discharged with MR≤2+ (primary effectiveness endpoint). Clinical 1-month follow-up data showed an improvement in NYHA functional class (42 patients (70%) in NYHA class I-II). 60 of 62 (97 %) successfully treated patients were free from death and mitral valve surgery at 1-month follow-up. MitraClip therapy reduces functional MR with acute MR reduction to <2+ in the great majority of patients, with a large freedom from death, surgery or recurrent MR in a great portion of patients.

Keywords: MitraClip, mitral regurgitation, heart valves, catheter-based therapy

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Authors: C. Miranda, R. Soares, S. Cunha, L. Ferreira, G. Igrejas, P. Poeta

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Different animal species, including ornamental animals, are reported as potential reservoirs of antibiotic resistance genes. Consequently, these resistances can be disseminated in the environment and transferred to humans. Moreover, multidrug-resistant bacteria reduce the efficacy of antibiotics, as the case of vancomycin-resistant enterococci. Enterococcus faecalis and E. faecium are described as the main nosocomial pathogens. In this line, the aim of this study was to characterize resistance and virulence genes of enterococci species isolated from samples of food supplied to ornamental animals during 2020. The 29 enterococci isolates (10 E. faecalis and 19 E. faecium) were tested for the presence of the resistance genes for the following antibiotics: erythromicyn (ermA, ermB and ermC), tetracycline (tetL, tetM, tetK and tetO), quinupristin/dalfopristin (vatD and vatE), gentamicin (aac(6’)-aph(2’’)-Ia), chloramphenicol (catA), streptomycin (ant(6)-Ia) and vancomycin (vanA and vanB). The same isolates were also tested for 10 virulence factors genes (esp, ace, gelE, agg, fsr, cpd, cylA, cylB, cylM and cylLL). The resistance and virulence genes were performed by PCR, using specific primers and conditions. Negative and positive controls were used in all PCR assays. The most prevalent resistance genes detected in both enterococci species were ermB (n=15, 52%), ermC (n=7, 24%), tetK (n=8, 28%) and vatE (n=4, 14%). Resistance genes for vancomycin were found in ten (34%) E. faecalis and ten (34%) E. faecium isolates. Only E. faecium isolates showed the presence of ermA (n=2, 7%), tetL (n=13, 45%) and ant(6)-Ia gene (n=4, 14%). A total of nine (31%) enterococci isolates were classified as multidrug-resistant bacteria (3 E. faecalis and 6 E. faecium). In three E. faecalis and one E. faecium were not detected resistance genes. The virulence genes detected in both species were agg (n=6, 21%) and cylLL (n=11, 38%). In general, each isolate showed only one of these virulence genes. Five E. faecalis and eleven E. faecium isolates were negative for all analyzed virulence genes. These preliminary results showed the presence of multidrug-resistant enterococci in food supplied to ornamental animals, in particular vancomycin-resistant enterococci. This genotypic characterization reinforces the relevance to public health in the control of antibiotic-resistant bacteria.

Keywords: antibiotic resistance, enterococci, feed, ornamental animals

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Authors: Aneia Rajiel Busmente, Renato Gunio Jr., Jazin Mautante, Denise Joy Mendoza, Raymond Benedict Tagorio, Gabriel Uy, Natalie Quinn Valenzuela, Ma. Elayza Villa, Francine Yezha Vizcarra, Sofia Madelle Yapan, Eugene Kurt Yboa

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COVID-19’s rapid spread caused a dramatic change in the nation, especially the educational system. The Department of Education was forced to adopt a practical learning platform without neglecting health, a printed modular distance learning. The Philippines' K–12 curriculum includes Statistics and Probability as one of the key courses as it offers students the knowledge to evaluate and comprehend data. Due to student’s difficulty and lack of understanding of the concepts of Statistics and Probability in Normal Distribution. The Self-Learning Module in Statistics and Probability about the Normal Distribution created by the Department of Education has several problems, including many activities, unclear illustrations, and insufficient examples of concepts which enables learners to have a difficulty accomplishing the module. The purpose of this study is to determine the effectiveness of self-learning module on the academic performance of students in the subject Statistics and Probability, it will also explore students’ perception towards the quality of created Self-Learning Module in Statistics and Probability. Despite the availability of Self-Learning Modules in Statistics and Probability in the Philippines, there are still few literatures that discuss its effectiveness in improving the performance of Senior High School students in Statistics and Probability. In this study, a Self-Learning Module on Normal Distribution is evaluated using a quasi-experimental design. STEM students in Grade 11 from National University's Nazareth School will be the study's participants, chosen by purposive sampling. Google Forms will be utilized to find at least 100 STEM students in Grade 11. The research instrument consists of 20-item pre- and post-test to assess participants' knowledge and performance regarding Normal Distribution, and a Likert scale survey to evaluate how the students perceived the self-learning module. Pre-test, post-test, and Likert scale surveys will be utilized to gather data, with Jeffreys' Amazing Statistics Program (JASP) software being used for analysis.

Keywords: self-learning module, academic performance, statistics and probability, normal distribution

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Authors: Renato Morbidelli, Carla Saltalippi, Alessia Flammini, Marco Cifrodelli, Corrado Corradini

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The trend of magnitude and frequency of extreme rainfalls seems to be different depending on the investigated area of the world. In this work, the impact of climate change on extreme rainfalls in Umbria, an inland region of central Italy, is examined using data recorded during the period 1921-2015 by 10 representative rain gauge stations. The study area is characterized by a complex orography, with altitude ranging from 200 to more than 2000 m asl. The climate is very different from zone to zone, with mean annual rainfall ranging from 650 to 1450 mm and mean annual air temperature from 3.3 to 14.2°C. Over the past 15 years, this region has been affected by four significant droughts as well as by six dangerous flood events, all with very large impact in economic terms. A least-squares linear trend analysis of annual maximums over 60 time series selected considering 6 different durations (1 h, 3 h, 6 h, 12 h, 24 h, 48 h) showed about 50% of positive and 50% of negative cases. For the same time series the non-parametrical Mann-Kendall test with a significance level 0.05 evidenced only 3% of cases characterized by a negative trend and no positive case. Further investigations have also demonstrated that the variance and covariance of each time series can be considered almost stationary. Therefore, the analysis on the magnitude of extreme rainfalls supplies the indication that an evident trend in the change of values in the Umbria region does not exist. However, also the frequency of rainfall events, with particularly high rainfall depths values, occurred during a fixed period has also to be considered. For all selected stations the 2-day rainfall events that exceed 50 mm were counted for each year, starting from the first monitored year to the end of 2015. Also, this analysis did not show predominant trends. Specifically, for all selected rain gauge stations the annual number of 2-day rainfall events that exceed the threshold value (50 mm) was slowly decreasing in time, while the annual cumulated rainfall depths corresponding to the same events evidenced trends that were not statistically significant. Overall, by using a wide available dataset and adopting simple methods, the influence of climate change on the heavy rainfalls in the Umbria region is not detected.

Keywords: climate changes, rainfall extremes, rainfall magnitude and frequency, central Italy

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Authors: Carolina S. Monteiro, Eugénia Pinto, Miguel A. Faria, Sara C. Cunha

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About half of the world's population eats rice daily, making it the primary food source for billions of people. Besides its nutrition potential, rice can be a significant route of exposure to many contaminants. Mycotoxins are an example of such contaminants that can be present in rice. Among them, ochratoxin (OTA), citrinin (CIT), and zearalenone (ZEN) are frequently reported in rice. During digestion, only a fraction of mycotoxins from food can be absorbed (bioaccessible fraction), influencing their ability to cause toxic effects. Insufficient knowledge of the bioavailability of mycotoxins, alone and in combination, may hinder an accurate risk assessment of contaminants ingested by humans. In this context, two different rice (Oryza sativa) varieties, Carolino white and Carolino brown, both with and without turmeric, were boiled and individually spiked with OTA, CIT, and ZEN plus with its combination. Subsequently, samples were submitted to the INFOGEST harmonized in vitro digestion protocol to evaluate the bioaccessibility of mycotoxins. Afterward, the in vitro intestinal transport of the mycotoxins, both alone and in combination, was evaluated in digests of Carolino white rice with and without turmeric. Assays were performed with a monolayers of of Caco-2 and HT-29 cells. Bioaccessibility of OTA and ZEN, alone and in combination, were similar in Carolino white and brown rice with or without turmeric. For CIT, when Carolino white rice was used, the bioaccessibility was higher alone than in combination (62.00% vs. 25.00%, without turmeric; 87.56% vs. 53.87%, with turmeric); however, with Carolino brown rice was the opposite (66.38% vs. 75.20%, without turmeric; 43.89% vs. 59.44%, with turmeric). All the mycotoxins, isolated, reached the higher bioaccessibility in the Carolino white rice with turmeric (CIT: 87.56%; OTA: 59.24%; ZEN: 58.05%). When mycotoxins are co-present, the higher bioaccessibility of each one varies with the type of rice. In general, when turmeric is present, bioaccessibility increases, except for CIT, using Carolino brown rice. Concerning the intestinal absorption in vitro, after 3 hours of transport, all mycotoxins were detected in the basolateral compartment being thus transported through the cells monolayer. ZEN presented the highest fraction absorbed isolated and combined, followed by CIT and OTA. These findings highlight that the presence of other components in the complex dietary matrix, like turmeric, and the co-presence of mycotoxins can affect its final bioavailability with obvious implications for health risk. This work provides new insights to qualitatively and quantitatively describe mycotoxin in rice fate during human digestion and intestinal absorption and further contribute to better risk assessment.

Keywords: bioaccessibility, digestion, intestinal absorption, mycotoxins

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Authors: O. Ojeda Mena, Y. Cressault, P. Teulet, J. P. Gonnet, D. F. N. Santos, MD. Cunha, M. S. Benilov

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The assumption of plasma in local thermal equilibrium (LTE) is commonly used to perform electric arc simulations for industrial applications. This assumption allows to model the arc using a set of magneto-hydromagnetic equations that can be solved with a computational fluid dynamic code. However, the LTE description is only valid in the arc column, whereas in the regions close to the electrodes the plasma deviates from the LTE state. The importance of these near-electrode regions is non-trivial since they define the energy and current transfer between the arc and the electrodes. Therefore, any accurate modelling of the arc must include a good description of the arc-electrode phenomena. Due to the modelling complexity and computational cost of solving the near-electrode layers, a simplified description of the arc-electrode interaction was developed in a previous work to study a steady high-pressure arc discharge, where the near-electrode regions are introduced at the interface between arc and electrode as boundary conditions. The present work proposes a similar approach to simulate the arc ignition in a free-burning arc configuration following an LTE description of the plasma. To obtain the transient evolution of the arc characteristics, appropriate boundary conditions for both the near-cathode and the near-anode regions are used based on recent publications. The arc-cathode interaction is modeled using a non-linear surface heating approach considering the secondary electron emission. On the other hand, the interaction between the arc and the anode is taken into account by means of the heating voltage approach. From the numerical modelling, three main stages can be identified during the arc ignition. Initially, a glow discharge is observed, where the cold non-thermionic cathode is uniformly heated at its surface and the near-cathode voltage drop is in the order of a few hundred volts. Next, a spot with high temperature is formed at the cathode tip followed by a sudden decrease of the near-cathode voltage drop, marking the glow-to-arc discharge transition. During this stage, the LTE plasma also presents an important increase of the temperature in the region adjacent to the hot spot. Finally, the near-cathode voltage drop stabilizes at a few volts and both the electrode and plasma temperatures reach the steady solution. The results after some seconds are similar to those presented for thermionic cathodes.

Keywords: arc-electrode interaction, thermal plasmas, electric arc simulation, cold electrodes

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Authors: Gabriela D. Silva, Rodrigo L. O. R. Cunha, Mauricio D. Coutinho-Neto

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In the last four decades the biological activities of selenium compounds has received great attention, particularly for hypervalent derivates from selenium (IV) used as enzyme inhibitors. The unregulated activity of cysteine proteases are related to the development of several pathologies, such as neurological disorders, cardiovascular diseases, obesity, rheumatoid arthritis, cancer and parasitic infections. These enzymes are therefore a valuable target for designing new small molecule inhibitors such as selenuranes. Even tough there has been advances in the synthesis and design of new selenuranes based inhibitors, little is known about their mechanism of action. It is a given that inhibition occurs through the reaction between the thiol group of the enzyme and the chalcogen atom. However, several open questions remain about the nature of the mechanism (associative vs. dissociative) and about the nature of the reactive species in solution under physiological conditions. In this work we performed a theoretical investigation on model systems to study the possible routes of substitution reactions. Nucleophiles may be present in biological systems, our interest is centered in the thiol groups from the cysteine proteases and the hydroxyls from the aqueous environment. We therefore expect this study to clarify the possibility of a route reaction in two stages, the first consisting of the substitution of chloro atoms by hydroxyl groups and then replacing these hydroxyl groups per thiol groups in selenuranes. The structures of selenuranes and nucleophiles were optimized using density function theory along the B3LYP functional and a 6-311+G(d) basis set. Solvent was treated using the IEFPCM method as implemented in the Gaussian 09 code. Our results indicate that hydrolysis from water react preferably with selenuranes, and then, they are replaced by the thiol group. It show the energy values of -106,0730423 kcal/mol for dople substituition by hydroxyl group and 96,63078511 kcal/mol for thiol group. The solvatation and pH reduction promotes this route, increasing the energy value for reaction with hydroxil group to -50,75637672 kcal/mol and decreasing the energy value for thiol to 7,917767189 kcal/mol. Alternative ways were analyzed for monosubstitution (considering the competition between Cl, OH and SH groups) and they suggest the same route. Similar results were obtained for aliphatic and aromatic selenuranes studied.

Keywords: chalcogenes, computational study, cysteine proteases, enzyme inhibitors

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Authors: Carolina S. Monteiro, Eugénia Pinto, Miguel A. Faria, Sara C. Cunha

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Rice (Oryza sativa) production plays a vital role in reducing hunger and poverty and assumes particular importance in low-income and developing countries. Rice is a sensitive plant, and production occurs strictly where suitable temperature and water conditions are found. Climatic changes are likely to affect worldwide, and some models have predicted increased temperatures, variations in atmospheric CO₂ concentrations and modification in precipitation patterns. Therefore, the ongoing climatic changes threaten rice production by increasing biotic and abiotic stress factors, and crops will grow in different environmental conditions in the following years. Around the world, the effects will be regional and can be detrimental or advantageous depending on the region. Mediterranean zones have been identified as possible hot spots, where dramatic temperature changes, modifications of CO₂ levels, and rainfall patterns are predicted. The actual estimated atmospheric CO₂ concentration is around 400 ppm, and it is predicted that it can reach up to 1000–1200 ppm, which can lead to a temperature increase of 2–4 °C. Alongside, rainfall patterns are also expected to change, with more extreme wet/dry episodes taking place. As a result, it could increase the migration of pathogens, and a shift in the occurrence of mycotoxins, concerning their types and concentrations, is expected. Mycotoxigenic spoilage fungi can colonize the crops and be present in all rice food chain supplies, especially Penicillium species, mainly resulting in ochratoxin A (OTA) contamination. In this scenario, the objectives of the present study are evaluating the effect of temperature (20 vs. 25 °C), CO₂ (400 vs. 1000 ppm), and water stress (0.93 vs 0.95 water activity) on growth and OTA production by a Penicillium nordicum strain in vitro on rice-based media and when colonizing layers of raw rice. Results demonstrate the effect of temperature, CO₂ and drought on the OTA production in a rice-based environment, thus contributing to the development of mycotoxins predictive models in climate change scenarios. As a result, improving mycotoxins' surveillance and monitoring systems, whose occurrence can be more frequent due to climatic changes, seems relevant and necessary. The development of prediction models for hazard contaminants presents in foods highly sensitive to climatic changes, such as mycotoxins, in the highly probable new agricultural scenarios is of paramount importance.

Keywords: climate changes, ochratoxin A, penicillium, rice

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Authors: Rosely Sichieri, Bruna K. Hassan, Michele Sgambato, Barbara S. N. Souza, Rosangela A. Pereira, Edna M. Yokoo, Diana B. Cunha

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Obesity is increasing at a fast rate in low and middle-income countries where few school-based obesity interventions have been conducted. Results of obesity prevention studies are still inconclusive mainly due to underestimation of sample size in cluster-randomized trials and overestimation of changes in body mass index (BMI). The pooled analysis in the present study overcomes these design problems by analyzing 4,448 students (mean age 11.7 years) from three randomized behavioral school-based interventions, conducted in public schools of the metropolitan area of Rio de Janeiro, Brazil. The three studies focused on encouraging students to change their drinking and eating habits over one school year, with monthly 1-h sessions in the classroom. Folders explaining the intervention program and suggesting the participation of the family, such as reducing the purchase of sodas were sent home. Classroom activities were delivered by research assistants in the first two interventions and by the regular teachers in the third one, except for culinary class aimed at developing cooking skills to increase healthy eating choices. The first intervention was conducted in 2005 with 1,140 fourth graders from 22 public schools; the second, with 644 fifth graders from 20 public schools in 2010; and the last one, with 2,743 fifth and sixth graders from 18 public schools in 2016. The result was a non-significant change in BMI after one school year of positive changes in dietary behaviors associated with obesity. Pooled intention-to-treat analysis using linear mixed models was used for the overall and subgroup analysis by BMI status, sex, and race. The estimated mean BMI changes were from 18.93 to 19.22 in the control group and from 18.89 to 19.19 in the intervention group; with a p-value of change over time of 0.94. Control and intervention groups were balanced at baseline. Subgroup analyses were statistically and clinically non-significant, except for the non-overweight/obese group with a 0.05 reduction of BMI comparing the intervention with control. In conclusion, this large pooled analysis showed a very small effect on BMI only in the normal weight students. The results are in line with many of the school-based initiatives that have been promising in relation to modifying behaviors associated with obesity but of no impact on excessive weight gain. Changes in BMI may require great changes in energy balance that are hard to achieve in primary prevention at school level.

Keywords: adolescents, obesity prevention, randomized controlled trials, school-based study

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Authors: A. G. Cunha, M. Inácio, M. C. Freitas, C. Antunes, T. Silva, C. Andrade, V. Lopes

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Saltmarshes are essential ecosystems both from an ecological and biological point of view. Furthermore, they constitute an important social niche, providing valuable economic and protection functions. Thus, understanding their rates and patterns of sedimentation is critical for functional management and rehabilitation, especially in an SLR scenario. The Sado estuary is located 40 km south of Lisbon. It is a bar built estuary, separated from the sea by a large sand spit: the Tróia barrier. Caldeira de Tróia is located on the free edge of this barrier, and encompasses a salt marsh with ca. 21,000 m². Sediment cores were collected in the high and low marshes and in the mudflat area of the North bank of Caldeira de Tróia. From the low marsh core, fifteen samples were chosen for ²¹⁰Pb and ¹³⁷Cs determination at University of Geneva. The cores from the high marsh and the mudflat are still being analyzed. A sedimentation rate of 2.96 mm/year was derived from ²¹⁰Pb using the Constant Flux Constant Sedimentation model. The ¹³⁷Cs profile shows a peak in activity (1963) between 15.50 and 18.50 cm, giving a 3.1 mm/year sedimentation rate for the past 53 years. The adopted sea level rise scenario was based on a model built with the initial rate of SLR of 2.1 mm/year in 2000 and an acceleration of 0.08 mm/year². Based on the harmonic analysis of Setubal-Tróia tide gauge of 2005 data, the tide model was estimated and used to build the tidal tables to the period 2000-2016. With these tables, the average mean water levels were determined for the same time span. A digital terrain model was created from LIDAR scanning with 2m horizontal resolution (APA-DGT, 2011) and validated with altimetric data obtained with a DGPS-RTK. The response model calculates a new elevation for each pixel of the DTM for 2050 and 2100 based on the sedimentation rates specific of each environment. At this stage, theoretical values were chosen for the high marsh and the mudflat (respectively, equal and double the low marsh rate – 2.92 mm/year). These values will be rectified once sedimentation rates are determined for the other environments. For both projections, the total surface of the marsh decreases: 2% in 2050 and 61% in 2100. Additionally, the high marsh coverage diminishes significantly, indicating a regression in terms of maturity.

Keywords: ¹³⁷Cs, ²¹⁰Pb, saltmarsh, sea level rise, response model

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Authors: Alexsandro Bayestorff da Cunha, Dpebora Caline de Mello, Camila Alves Corrêa

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In the production of fiberboards, an adhesive based on urea-formaldehyde resin is used, which has the advantages of low cost, homogeneity of distribution, solubility in water, high reactivity in an acid medium, and high adhesion to wood. On the other hand, as a disadvantage, there is low resistance to humidity and the release of formaldehyde. The objective of the study was to determine the viability of adding industrial boiler ash to the urea formaldehyde-based adhesive for the production of medium-density fiberboard. The raw material used was composed of Pinus spp fibers, urea-formaldehyde resin, paraffin emulsion, ammonium sulfate, and boiler ash. The experimental plan, consisting of 8 treatments, was completely randomized with a factorial arrangement, with 0%, 1%, 3%, and 5% ash added to the adhesive, with and without the application of a catalyst. In each treatment, 4 panels were produced with density of 750 kg.m⁻³, dimensions of 40 x 40 x 1,5 cm, 12% urea formaldehyde resin, 1% paraffin emulsion and hot pressing at a temperature of 180ºC, the pressure of 40 kgf/cm⁻² for a time of 10 minutes. The different compositions of the adhesive were characterized in terms of viscosity, pH, gel time and solids, and the panels by physical and mechanical properties, in addition to evaluation using the IMAL DPX300 X-ray densitometer and formaldehyde emission by the perforator method. The results showed a significant reduction of all adhesive properties with the use of the catalyst, regardless of the treatment; while the percentage increase of ashes provided an increase in the average values of viscosity, gel time, and solids and a reduction in pH for the panels with a catalyst; for panels without catalyst, the behavior was the opposite, with the exception of solids. For the physical properties, the results of the variables of density, compaction ratio, and thickness were equivalent and in accordance with the standard, while the moisture content was significantly reduced with the use of the catalyst but without the influence of the percentage of ash. The density profile for all treatments was characteristic of medium-density fiberboard, with more compacted and dense surfaces when compared to the central layer. For thickness, the swelling was not influenced by the catalyst and the use of ash, presenting average values within the normalized parameters. For mechanical properties, the influence of ashes on the adhesive was negatively observed in the modulus of rupture from 1% and in the traction test from 3%; however, only this last property, in the percentages of 3% and 5%, were below the minimum limit of the norm. The use of catalyst and ashes with percentages of 3% and 5% reduced the formaldehyde emission of the panels; however, only the panels that used adhesive with catalyst presented emissions below 8mg of formaldehyde / 100g of the panel. In this way, it can be said that boiler ash can be added to the adhesive with a catalyst without impairing the technological properties by up to 1%.

Keywords: reconstituted wood panels, formaldehyde emission, technological properties of panels, perforator

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