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Annals of the Brazilian Academy of Sciences

AABC - Volume 88 (2) - June 2016


This issue of the Annals of the Brazilian Academy of Sciences presents a total of 35 original contributions about a variety of subjects, ranging from Physics to Social Sciences. Contrary to previous volumes, the majority of papers presented here belong to Agrarian Sciences, and there is a growing trend in the last years of submissions in this area. Among the highlights is a study on several aspects of potato quality after irradiation with different doses of Cobalt-60. The ultimate aim of this kind of research is to increase shelf life of vegetables for human consumption. Other contributions regarding Agrarian Sciences published here focus on methods that assess the quality of grains during storing procedures, meat quality, charcoal identification, stability of anthocyanins, soil and water management, and the assessment of soil phosphatase.

In Chemical Sciences, this volume presents a contribution that addresses the question on how mercury - a dangerous pollutant - is transferred and accumulated in some fish with some quite interesting results.

Regarding Earth Sciences, there are two papers on paleontology: the first analyzing the diversity of glyptodonts, an extinct group of armored herbivore mammals that resembles modern armadillos and are important elements of the megafauna (giant mammals that once roomed the Earth); and the second describing new fossils of late Pleistocene echimyids - a group of rodents including spiny rats, tree rats and the coypu that are still quite diverse in South America nowadays. There is also a study comparing dating methods of human and shell remains from a site located in northeastern Brazil.

Others highlights of this issue include two interesting contributions addressing the problematic of fish contamination by nematode larvae and phenol concentration, respectively (Biological Sciences); a meta-analysis regarding mesothelin, that is used as a biomarker for a widespread woman disease: ovarian carcinoma (Health Sciences); and a new method that establishes the influence of lake morphology regarding evaporation and reservoir yield (Engineering Sciences).

Last but not least, I would like to call your attention to a paper that discusses the interaction of Brazilian scientists and the media (Social Sciences).

Please keep in mind that since 2000 all papers published by the AABC can be downloaded free of charge at the SciELO site and previous edition of the Newsletter are available at the ABC website.

We are now inviting you to scroll through the text and click on the title of the article that interests you!

Alexander W. A. Kellner






1-Relevance of Hydrodynamic Effects for the Calculation of Outer Surface Potential of Biological Membrane Using Electrophoretic Data
Authors: Izan M. Junior, Maria Clícia S. Castro, Dilson Silva and Célia M. Cortez

Modelling the cell membrane as a complex structure including two outer charged interfaces separated by non-neglectful distance (glycocalyx length) shows that the classical Helmholtz-Smoluchowski’s model is not able to represent the forces responsible to the electrophoretic behavior of cell, because it does not take account the hydrodynamic effects of glycocalyx. Electromechanical characteristics of this complex physical system that covers the cellular surface cannot be neglected, evidencing the need to review the concept of “cellular surface potential”. The classical model represents a limiting case for models taking into account hydrodynamic effects to describe the velocity distribution in the electrophoretic motion.     

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2-Tunneling effects in resonant acoustic scattering of an air bubble in unbounded water
Authors: André G. Simão and Luiz G. Guimarães

The problem of sound wave scattering by a spherical air bubble in unbounded water is a tradition in physics thus leaving nearly no space for new contributions. However, the present work explores a method based on the analogy between quantum potential scattering and acoustic scattering. The model, developed from the proposed analogy, permitted an explicit treatment of the issue related to the role played by wave tunneling in the acoustic resonances of the bubble. Among the theoretical results obtained, highlight is given to the understanding of the mechanism that makes the bubble a remarkable object to store energy.

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3-Application of modified simplex on the development of a preconcentration system for cadmium determination in sediments, food and cigarettes
Authors: Queila O. Santos, Islania Moreno, Leandro dos Santos, Aldenor G. Santos, Valdinei S. Souza and Marcos A. Bezerra

In the present work, modified simplex was employed to optimize a preconcentration system based on solid-phase extraction using XAD-2 resin functionalized with 3,4-dihydroxybenzoic acid for Cd determination by flame atomic absorption spectrometry. The use of a modified simplex algorithm allowed a fast and efficient optimization of the system demanding a small number of experiments and reducing the analysis time and reagent consumption. The developed method presented analytical characteristics (limit of quantification, enrichment factor, precision and accuracy) suitable for cadmium determination in samples of sediments, cigarettes and food.   

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4-Mercury bioaccumulation and isotopic relation between Trichiurus lepturus (Teleostei) and its preferred prey in coastal waters of southeastern Brazil
Authors: Vanessa T. Bittar, Carlos E. Rezende, Helena A. Kehrig and Paula M. Di Beneditto

The transfer of mercury via food resources and its bioaccumulation from prey species to the fish Trichiurus lepturus was analysed in southeastern Brazil. The isotopic relation between this fish and its prey allowed inferences on prey assimilation and predator feeding habits. The values of mercury and nitrogen isotope highlighted the juvenile specimens of T. lepturus as the main via of this element to the adult specimens, and the most assimilated prey. Thus, cannibalism is confirming as an important feeding strategy to this predator. The isotopic relation between predator and its prey species showed a feeding activity preferably coastal and pelagic. 

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5-Regarding the real diversity of Glyptodontidae (Mammalia, Xenarthra) in the late Pliocene (Chapadmalalan Age/Stage) of Argentina
Authors: Alfredo E. Zurita, Matías Taglioretti, Martín de Los Reyes, Francisco Cuadrelli and Daniel Poire

Glyptodonts constitute a conspicuous and diversified group of large South American armored mammalian herbivores, reaching during some lapses enormous sizes. Although the knowledge we have in that concerning the southern South American diversity is relatively good, some lapses are particularly critical. This is evident in the late Neogene of Argentina, where most of the species of glyptodonts from this period were recognized. Our study reveals that the high diversity of glyptodonts for that lapse is much more limited than previously supposed. These results are in agreement with the relatively low diversity of glyptodonts recorded in some lapses of its extensive biochron.

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6-Late Pleistocene echimyid rodents (Rodentia, Hystricognathi) from northern Brazil
Authors: Thais M.F. Ferreira, Adriana Itati Olivares, Leonardo Kerber, Rodrigo P. Dutra and Leonardo S. Avilla

Echimyidae (spiny rats, tree rats and the coypu) is the most diverse family of extant South American hystricognath rodents (caviomorphs). We describe fossils of late Pleistocene echimyids found in a karst deposit, Gruta dos Moura cave, in southern Tocantins, northern Brazil. The analyzed specimens are assigned as Thrichomys sp., Makalata cf. didelphoides and Proechimys sp. This is the first time that a fossil of Makalata is reported. Data reported contribute to the understanding of the ancient diversity of rodents of this region during the Pleistocene.

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7-Dating of fossil human teeth and shells from Toca do Enoque site at Serra das Confusões National Park, Brazil
Authors: Angela Kinoshita, Henry L. Sullasi, Viviane K. Asfora, Renata L. Azevedo, Pedro Guzzo, Niede Guidon, Ana Maria G. Figueiredo, Helen Khoury, Anne-Marie Pessis and Oswaldo Baffa

Dating is an important task to help reconstruct history. A fossil human tooth and shell found at the archaeological site Toca do Enoque located in Serra das Confusões National Park (Piauí, Brazil) were dated by physical techniques. An excavation unearthed three sepulchers with human skeletons and some shells. Two Brazilian laboratories, USP and UFPE, independently performed Electron Spin Resonance (ESR) dating of the samples and obtained similar ages for both (~4.8 kyBP). The results agreed with C-14 dating of the shell and other samples collected in the same sepulcher. Therefore, this work provides a successful inter-comparison of ESR dating for this range of ages.

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8-Nematode larvae infecting Priacanthus arenatus Cuvier, 1829 (Pisces: Teleostei) in Brazil
Authors: Bianca P. Kuraiem, Marcelo Knoff, Nilza N. Felizardo, Delir C. Gomes and Sérgio C. São Clemente

Specimens of Priacanthus arenatus commercialized in the cities of Niterói and Rio de Janeiro, State of Rio de Janeiro, were acquired. The fish were necropsied and filleted to investigate the presence of nematode larvae. Twenty fish (66.7%) out of the total were parasitized by nematode larvae. A total of 2024 larvae were collected; among them, 30 third-instar larvae of Anisakis sp. parasitizing caecum, stomach, liver, and mesentery; and 1,994 third-instar larvae of Hysterothylacium deardorffoverstreetorum parasitizing spleen, caecum, stomach, liver, mesentery, and abdominal muscle. This is the first report of H. deardorffoverstreetorum and Anisakis sp. larvae parasitizing P. arenatus.

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9-Metabolic responses of channel catfish (Ictalurus punctatus) exposed to phenol and post-exposure recovery
Authors: Fernanda D. Moraes, Priscila A. Rossi, Juliana S.L. Figueiredo, Francine P. Venturini, Lucas R.X. Cortella and Gilberto Moraes

Channel catfish (Ictalurus punctatus) is adversely affected by sublethal concentration of phenol. Biochemical biomarkers and metabolic routes were proposed in order to understand the intermediary metabolism of the contaminated fish. Carbohydrates, proteins and fat stores were used to attend the high metabolic demand, resulting from stress and detoxification processes. The fish depicted a catabolic preference for lipids to cope with phenol. Metabolic alterations after post-exposure recovery period indicate compensation or adaptation was not achieved by I. punctatus. The high metabolic losses of I. punctatus exposed to phenol bring attention to the consequences of environmental contamination.

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10-Palynological analysis of Dennstaedtiaceae taxa from the Paranaense Phytogeographic Province that produce Trilete spores II: Microlepia speluncae and Pteridium arachnoideum
Authors: Agustina Yañez, Gonzalo J. Marquez and Marta A. Morbelli

This paper is part of the palynological study for Dennstaedtiaceae family growing in the Paranaense Phytogeographic Province, also known as Paraná Forest Province and Araucaria Forest Province. The purpose of this work is to make a comparative analysis of the Microlepia speluncae and Pteridium arachnoideum spore morphology of the Paranaense Province with LM, SEM, and TEM. The results of this paper indicate that spore morphology and perispore ultrastructure allow differentiating Microlepia from Pteridium but also to the other Dennstaedtiaceae genera that grow in the Paranaense Province. 

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11-The influence of fire on the assemblage structure of foraging birds in grasslands of the Serra da Canastra National Park, Brazil
Authors: Matheus G. Reis, Carolline Z. Fieker and Manoel M. Dias

In grasslands of “Serra da Canastra”, southern Cerrado (Brazilian savanna), we investigated the structure of bird assemblages, comparing areas affected by natural fires to the areas where controlled fires were set as a management strategy to combat arson. The results indicated that both types of burnings triggered immediate changes in bird assemblages, increasing the number of species and individuals. Natural fires exhibited a more significant influence on diversity and dominance. The differences were no longer noticeable after 2–3 months (prescribed burnings) and 3-4 months (natural fires). The findings may help the understanding of fire effects on bird assemblages in grasslands.

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12-Seasonality of reproduction of epiphytic bryophytes in flooded forests from the Caxiuanã National Forest, Eastern Amazon
Authors: Gabriela R. Cerqueira, Anna Luiza Ilkiu-Borges and Leandro V. Ferreira

The manuscript named Seasonality of reproduction of epiphytic bryophytes in floodedforests from the Caxiuanã National Forest, Eastern Amazon resulted of a pioneering study in the Amazonia bioma, to produce knowledge on reproductive aspects of the epiphyte bryoflora on phorophytes of Virola surinamensis in flooded forests. The study  investigated if variation  exist in the reproduction forms of bryophyte species between the most dry and most wet months, as well as detailed aspects related to the presence of structures that indicate fertility, structures of sexual and assexual reproduction.

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13-Intestinal and liver morphometry of the Yellow Tail Tetra (Astyanax altiparanae) fed with oregano oil
Authors: Pollyanna M.F. Ferreira, Débora W. Caldas, Ana Lúcia Salaro, Sirlene S.R. Sartori, Jerusa M. Oliveira, Alex J.S. Cardoso and Jener A.S. Zuanon

Knowledge of gut histology and the digestion and absorption processes of nutrients is essential for understanding fish physiology and nutrition. This knowledge can contribute to the formulation of fish diets and result in increased productivity and reduced production costs. The product that has potential for use as a growth promoter in diets is oregano oil (Origanum vulgare), due to its antimicrobial, antioxidant, anti-inflammatory and pro-digestive properties. The oregano essential oil promotes increased absorption areas, modulates the amount of goblet cells involved in protecting the intestinal mucosa and promotes cytoplasmic increase with greater deposition of liver glycogen in Astyanax altiparanae.

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14-Mesothelin as a biomarker for ovarian carcinoma: a meta-analysis
Authors: Kristian Madeira, Eduardo R. Dondossola, Bruna F. de Farias, Carla S. Simon, Maria C.M. Alexandre, Bruno R. Silva and Maria Inês Rosa

The human mesothelin is produced as a 69 kD polypeptide with a hydrophobic sequence at the end of a carboxyl group, which is removed and replaced by phosphatidylinositol. This glycosyl-phosphatidylinositol bond retains the mesothelin membrane of the cell. Mesothelin can be an important screening test for ovarian cancer interpreted by pooled specificity of 0.94 (95% CI 0.92 to 0.95) and pooled sensitivity of 0.62 (95% CI 0.58-0.66). It may be possible to increase the sensitivity of mesothelin in combination with other biomarkers, especially in the early stages of the disease.

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15-The effects of coconut oil supplementation on the body composition and lipid profile of rats submitted to physical exercise
Authors: Nathália M. Resende, Henrique R. Félix, Murillo R. Soré, Aníbal M.M. Neto, Kleber E. Campos and Gustavo T. Volpato

Physical exercise associated with adequate diet have been recommended as first option treatment for dyslipidemia. Studies showed that the use of coconut oil supplementation can reduce the accumulated fat, and its use presents many health benefits. Thus, it is noted an increasing number of coconut oil users. However, this study showed that the reduction of what causes dyslipidemia was evident only in the group that practiced physical exercises associated with coconut oil supplementation. It also showed that physical exercise yielded an adequate lipid profile in rats, presenting higher HDL-c and lower LDL-c and VLDL-c compared to sedentary ones. Hence, care is needed when using lipid supplements, mainly by sedentary people.

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16-Physico-chemical and sensory evaluation of potato (Solanum tuberosum L.) after irradiation
Authors: Ivanessa G.M. Soares, Edvane B. Silva, Ademir J. Amaral, Erilane C.L. Machado and Josenilda M. Silva

This research investigated the effects of ionizing radiation on the physico-chemical and sensory characteristics of the potato cultivar Ágata (Solanum tuberosum L.), with the ultimate goal of increasing shelf life. Groups of samples were harvested at maturation stage and separately exposed to a Cobalt-60 source, receiving different radiation doses.  The paper discusses several aspects, namely: budding, rot, loss of weight, texture, flesh color, moisture, external and internal appearance, aroma, soluble solids, titratable acidity, vitamin C, protein, starch and glucose. The methodology of irradiation of potato and the results of this work significantly contribute to reduce losses between field and table.

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17-Antioxidant activity of oils extract from orange (Citrus sinensis) seeds
Authors: Neuza Jorge, Ana Carolina da Silva and Caroline P.M. Aranha

The present study aims to characterize the oils extracted from seeds of Hamlin, Natal, Pera-rio and Valencia orange varieties (Citrus sinensis).The orange seed oils presented important content of total carotenoids (19.01 mg/kg), total phenolic compounds (4.43 g/kg), α-tocopherol (135.65 mg/kg) and phytosterols (1304.2 mg/kg). The antioxidant activity ranged from 56.0% (Natal) to 70.2% (Pera-rio). According to the results it is possible to conclude that the orange seed oils can be used as specialty oils in diet, since they contain considerable amounts of bioactive compounds and antioxidants.

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18-An examination of soil and water conservation practices in the paddy fields of Guilan province, Iran
Authors: Dayryoush Ashoori, Asgar Bagheri, Mohammad S. Allahyari, Ahmad S. AL-Rimawi

We studied the use of soil and water conservation (SWC) practices among rice farmers in Iran. Ten Agronomic and Physical measures were used for rating the farmers’ tendency to adopt SWC measures. Ratoon harvest and Crop rotation amongst agronomic measures, the use of a plastic mulch on the borders of rice fields and of bunds, flood walls and dams amongst physical measures were the most common practices, alternatively. Low level of use of SWC measures found among Guilan paddy farmers. In addition, younger farmers are more likely to engage in SWC practices.

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19-Floristic evolution in an agroforestry system cultivation in Southern Brazil
Authors: Luís C.R. Silva, Sebastião A. Machado, Franklin Galvão and Afonso Figueiredo Filho

Mimosa scabrella is widely used in Brazil for energy and its predominant cutting age is at seven years. If there is no cutting, the trees of M. scabrella gradually die until rare individuals of this species remain. At the same time, the understory becomes increasingly more diverse and abundant. This study shows the evolution and succession process of M. scabrella stands over twenty years. The results allow us to know the dynamics of the understory vegetation and generate relevant information to make the traditional management of this species more rational allowing the conservation of the other species.

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20-Bovine meat and bone meal is an economically viable alternative in quail feeding in the initial phase
Authors: Carla C. Pizzolante, Sérgio K. Kakimoto, José E. Moraes, Ana Paula O. Saccomani, Daniela F. Soares, Gustavo C. Paschoalin and Fábio E.L. Budiño

The costs with nutrition can reach about 70% of the total costs in poultry industry, due to this, it is interesting to evaluate alternative sources of protein that can reduce the production costs without affecting the productivity. In the present study, we investigated whether partial replacement of soybean meal (SBM) by meat and bone meal (MBM) in the diet of Japanese quail during the starter phase is a viable alternative that would maintain or improve their productive and economic performance. Our results show that the inclusion of MBM in the diet of quail reduces feeding costs by up to 6% without impairing productive performance.

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21-Branching, flowering and fruiting of Jatropha curcas treated with ethephon or benzyladenine and gibberellins
Authors: Anne P. Costa, Wagner Vendrame, Sílvia Nietsche, Jonathan Crane, Kimberly Moore and Bruce Schaffer

The use of plant growth regulators (PGR) could be an alternative to manipulate flower and seed production in Jatropha curcas. Our results showed that ethephon could play an important role on flower production, reducing the number of flowers as PGR concentration increased. In contrast, increasing concentrations of BA + GA4 +7 promoted an increase on seed dry weight, which could ultimately affect seed yield.

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22-In vitro antifungal activity of four chemotypes of Lippia alba (Verbenaceae) essential oils against Alternaria solani (Pleosporeaceae) isolates
Authors: Elisa Z. Tomazoni, Márcia R. Pansera, Gabriel F. Pauletti, Sidnei Moura, Rute T.S. Ribeiro and Joséli Schwambach

Several compounds produced by plant secondary metabolism have been proven to present antimicrobial action, enabling their use in phytopathogen control. They also present low environmental impact when compared to conventional pesticides. Essential oils contain these compounds and can be found in several plant species, such as Lippia alba. Essential oils of four chemotypes of L. alba (camphor, citral, linalool and camphor/1,8-cineole) were tested against the phytopathogen Alternaria solani, which causes early blight on tomatoes and is responsible for great economic losses regarding production. The chemotypes that had the best performance was citral and linalool, presenting fungicidal action against A. solani.

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23-Probiotic level effects on growth performance, carcass traits, blood parameters, cecal microbiota, and immune response of broilers
Authors: Mohammadreza Pourakbari, Alireza Seidavi, Leila Asadpour and Andrés Martínez

There is a public concern about food safety and antibiotic-resistant bacteria in humans. On the other hand, poultry farmers have to keep healthy flocks in order to maintain productivity and contribute to the health safety of the food chain. Probiotics might be alternatives to growth promoting antimicrobials in animal production. We observed that probiotics in broiler feed had positive effects on productive results, which could be related to a better digestion and absorption of the nutrients in the gut, and decreased the Escherichia coli counts in the gut contents. The optimal concentrations of probiotics in broiler feed deserve further investigations. 

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24-Development of Dichelops melacanthus and its egg parasitoid Telenomus podisi reared on Bt-soybean MON 87701 x MON 89788 and its near conventional isoline under different temperatures
Authors: Orcial C. Bortolotto, Adeney F. Bueno, Ynaiara K. Stopa, Gabriela V. Silva and Ana Paula Queiroz

Pest outbreaks can be impacted by different conditions. Temperature as well as the adoption of Bt-soybean can be directly or indirectly related to green belly increase recently reported. Therefore, Dichelops melacanthus biology was studied under constant temperatures (19, 25, and 31 ± 2 °C). In addition, the biology of Telenomus podisi was studied at 25 ± 2 °C. This study demonstrates that green belly is favored at high temperatures (31 ± 2 °C), and that MON 87701 × MON 89788 soybean pods do not affect the development of green belly or its parasitoid T. podisi.

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25-Assessment and kinetics of soil phosphatase in Brazilian savanna systems
Authors: Adão S. Ferreira, Suéllen P. Espíndola and Maria Rita C. Campos

Soil phosphatase is a primary indicator of soil quality in ecosystems. The present work aimed to evaluate the activity using different buffers and determine parameter kinetics of soil phosphatase in different land uses in Cerrado Soils. The Michaels-Menten equation and the Eadie-Hofstee model were used to evaluate the substrate affinity (Km) and enzymatic isoforms of soil phosphatases. The activity of soil phosphatase depended on buffers used. The native soil had a greater phosphatase activity than agricultural soils, but the Km value in native soils was lower. Results suggest that the native soil has a greater number of phosphatase isoforms. 

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26-A contribution to the identification of charcoal origin in Brazil II – Macroscopic characterization of Cerrado species
Authors: Thaís A.P. Gonçalves, Silvana Nisgoski, Julia S. Oliveira, Carmen R. Marcati, Adriano W. Ballarin and Graciela I.B. Muñiz

The Brazilian Cerrado is highly threatened by agricultural practices, livestock and charcoal production. It is very important to improve forestry supervision to contribute for the Biome’s conservation. Thus, in this work we present the macroscopic characterization of charcoal from 25 Cerrado’s species, simulating the real conditions of forest controllers. Therefore, it provides knowledge for government agents to verify the documents of forestry origin by fast analysing a sample of charcoal itself. Our results might give directions to future identification of genera or species.

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27-Extraction of bioactive compounds and free radical scavenging activity of purple basil (Ocimum basilicum L.) leaf extracts as affected by temperature and time
Authors: Alessandra C. Pedro, Fernanda Moreira, Daniel Granato and Neiva D. Rosso

The stability of anthocyanins from purple basil (Ocimum basilicum L.) in relation to temperature, light and copigmentation was also studied. The highest anthocyanin content was 67.40 mg/100 g extracted at 30 °C and 60 min. The extracts protected from light, in the presence of copigments, showed an increase in half-life from 152.67 h for the control to 856.49 and 923.17 h for extract in the presence of gallic acid and phytic acid, respectively. These results clearly indicate that purple basil is a potential source of stable bioactive compounds.

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28-Physiological behavior of bean’s seeds and grains during storage
Authors: Flávia D.R. Cassol, Andréa M.T. Fortes, Lorena C. Mendonça, Camila V. Buturi and Thaís R. Marcon

The physiological potential evaluation during storage aims to guarantee the seeds necessary vigor for the crop establishment in field. For this, the use of vigor tests provides quick and reliable answers for the seed quality characterization. Thus, it was possible verify that the physiological quality of beans from BRS Splendor cultivar was affected by storage, and that the accelerated aging and cold test, along with the germination velocity index, were the more sensible ones on detecting the decrease on vigor, during the 360 days of storage, under not controlled environmental conditions.  

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29-Influence of Duroc breed inclusion into Polidh Landrace maternal line on pork meat quality traits
Authors: Dominika Guzek, Dominika Głąbska, Krzysztof Głąbski and Agnieszka Wierzbicka

Crossbreeding with Duroc breed could allow to improve meat quality, but little attention is available regarding influence of specific crossbreeding. The effect of crossbreeding of Polish Landrace dames with Duroc sires on quality features of meat in reference to Polish Landrace breed indicated no effect on sarcomere length, shear force, despite influence on fat content. Moreover no statistically effect on components of color measured in CIE L*a*b* system was stated, while for hue angle influence was observed.

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30-Active inductor based fully integrated cmos transmit/receive switch for 2.4 GHz RF transceiver
Authors: Mohammad A.S. Bhuiyan, Yeoh Zijie, Jae S. Yu, Mamun B.I. Reaz, Noorfazila Kamal and Tae G. Chang

T/R switch is essential for every modern RF transceivers. T/R switches are expected to have high isolation and low insertion loss. In this study, a T/R switch with high isolation and low insertion loss has been designed by using Silterra 0.13µm CMOS process for 2.4GHz transceivers. Transistor aspect ratio optimization, proper gate bias resistance, resistive body floating and active inductor-based parallel resonance techniques have been implemented to achieve the goal. The proposed T/R switch exhibits 0.85dB insertion loss and 45.17dB isolation. Moreover, avoiding bulky inductor and capacitor results in a highly compact architecture of only 0.003 mm2.

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31-Interconnection between microstructure and microhardness of directionally solidified binary Al-6wt.%Cu and multicomponent Al-6wt.%Cu-8wt.%Si alloys
Authors: Angela J. Vasconcelos, Rafael H. Kikuchi, André S. Barros, Thiago A. Costa, Marcelino Dias, Antonio L. Moreira, Adrina P. Silva and Otávio L. Rocha

The Al-6wt.%Cu and Al-6wt.%Cu-8wt.%Si alloys have been directionally solidified to evaluate both the microstructural and microhardness. A characterization was performed including experimental dendrite growth rates and cooling rates by measuring Vickers microhardness, optical microscopy and scanning electron microscopy with microanalysis performed by energy dispersive spectrometry. The increasing of thermal parameters reduced the primary dendritic spacing increasing the microhardness. Furthermore, the incorporation of Si in Al-6wt.%Cu alloy to form the Al-6wt.%Cu-8wt.%Si alloy influenced the microstructure and consequently the microhardness. An analysis of the CET was also performed and the results showed that the CET in both cases is not sharp.

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32-Trade-off between reservoir yield and evaporation losses as a function of lake morphology in semi-arid Brazil
Authors: José N.B. Campos, Iran E. Lima Neto, Ticiana M.C. Studart and Luiz S.V. Nascimento

This study investigates the relationships between reservoir yield and evaporation as a function of lake morphology in semi-arid Brazil. A new methodology was proposed to classify the morphology of 40 reservoirs. Then, simulations were conducted to study the effect of morphology on the water storage process. The reservoirs were categorized as convex, slightly convex or linear. When the conical approximation was used instead of the real lake form, a trade-off occurred between yield and evaporation. Using the conical approximation, the water yield prediction errors reached about 5% of the mean annual inflow. However, for smaller reservoirs, this error became important.

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33-Equilibrium pricing and ordering policies in a two-echelon supply chain in the presence of strategic customers
Authors: Seyed J. Sadjadi, Jafar Naeij, Hasan Shavandi and Ahmad Makui

In this paper, we presented a comprehensive study of the customers’ behavior (i.e. myopic, strategic, and low value) in a two-echelon supply chain with a supplier and a monopolist retailer. The study attempted to bridge the existing gap, based on how customers’ strategic behaviors influence supply chain’s decision variable. We found out, the retailer’s equilibrium pricing strategy occurred in maximum valuation of strategic customer so that s/he prefers to wait, hoping to reduce the price. Furthermore, we have shown that the reverse dependence between wholesale price and ordering quantity can act as a leverage to control the retailer’s demand.

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34-Determinism, chaos, self -organization and entropy
Author: José Pontes

This paper discusses two changes of paradigm occurred in science along the XX century, which point to conflicts and backlashes resulting from excessive extrapolations: end of the mechanist determinism, and end of the apparent incompatibility between biology, where ordering is law, and physics, postulating a progressive loss of order in natural systems. We recognize today that order – but also chaos – emerge in far from equilibrium systems, and in large networks, sparsely connected. We also recognize that entropy decreases from building life are small, and trivially compensated for compliance with thermodynamics. Life emerges at a very low thermodynamic cost.

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35-Scientists in the public sphere: Interactions of scientists and journalists in Brazil
Authors: Luisa Massarani and Hans P. Peters

A survey with about 1,000 Brazilian scientists indicate that they have clear and high expectations about how journalists should act in reporting scientific information in the media, but such expectations do not always seem to be met. Nonetheless, 67% of them say that having their research covered by media has a positive impact on their reputation among their scientific colleagues. One quarter of the respondents expressed that talking to the media can facilitate acquisition of more funds for research. Of the total of respondents, 38% believe that writing about an interesting topic for release on media channels can facilitate research publication in a scientific journal.

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