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Annals of the Brazilian Academy of Sciences

AABC - Volume 87.3 - September 2015


In addition to the regular issue, the Annals of the Brazilian Academy of Sciences (AABC) have started to publish supplement issues that are specific to one area. The first of such supplements (87-2 Suppl) was on Hot Topics in Biomedical Sciences and has shown to be very successful. As a result, the number of papers in each regular issue tends to be slightly less than usual.

In volume 87(3) there are 32 papers in a variety of fields. Among the highlights is a study in Chemical Sciences of anthranilic acids that have applications in the food and perfumery industries and how to develop methods to deal with them.

In Earth Sciences, there is an interesting study that uses Landsat 5 TM images to estimate the gross primary production (GPP) of Amazon-Cerrado Transitional Forest and a paper that shows the environmental changes in the northernmost Brazilian Amazon region.

As usual, Biological Sciences is the area with most contributions. Papers range from the reproductive morphology of female Guinea dolphin to the anesthetic activity of essential oils. There are also studies of plant taxonomy and the relations between cyanobacterial abundance and environment.


Lastly, I would like to call your attention to a paper (Biomedical Sciences) that addresses the counteracting effects on free radicals of Casearia sylvestris, a plant with medicinal properties and the effects of onychomycosis on woman (Health Sciences).

Please note that the AABC are an open access journal and since 2000, all papers can be downloaded free of charge at the SciELO site. Now, I invite you to scroll through the text and click on the title of the articles that interest you!

Alexander W. A. Kellner




1 - Infinistesimal Hartman-Grobman Theorem in Dimension Three

Author: Clementa Alonso-González

The determination of the topological class to which a real analytic vector field X belongs, around a singularity, is based on reduction results that show the equivalence between X and a simpler vector field. The Hartman-Grobman theorem establishes that, in the hyperbolic case, the linear part is a representative of the topological type of X. It is natural to ask what happens when the linear part is null. Brunella and Miari (1990) showed that in dimension two, under non degeneracy conditions, the principal part of  X  given by the Newton polyhedron has the same topological type of X. In this paper we give the main ideas to generalize this result to dimension three.

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2 - An Analysis of Total Phosphorus Dispersion in Lake Used As a Municipal Water Supply

Authors: Rômulo C. Lima, André L.A. Mesquita, Claudio J.C. Blanco, Maria de Lourdes S. Santos and Yves Secretan

In this paper we present a computational simulation of the phosphorus pollution within a real lake produced by the water of the river that supplies it and domestic sewage dumps from the population living in its vicinity. The computer code is based on numerical solution of two-dimensional equation of advection-diffusion-reaction by the method ϴ/SUPG.

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3 - A new qualitative proof of a result on the real jacobian conjecture

Authors: Francisco Braun and Jaume Llibre

Let F be a polynomial endomorphism of the plane with Jacobian determinant always different from zero. In general, F is not injective. We prove that for the global injectivity of F it is enough to assume that the higher homogeneous parts of the components of the map do not have real linear common factors. This result is not new, but we deduce it using only techniques of Qualitative Theory of Differential Equations. Our proof indeed gives an application of a beautiful known relationship between injectivity of polynomial maps and centers of Hamiltonian systems in the plane.

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4 -Anthranilic acids from isatin: an efficient, versatile and environmentally friendly method

Authors: Gabriel F. Rio, Bárbara V. Silva, Sabrina T. Martinez and Angelo C. Pinto

Anthranilic acids have applications in the food and perfumery industries, and are used in the synthesis of bioactive molecules. This paper describes the preparation of 16 anthranilic acids in yields ranging from 51 to 97%, by treating isatins with NaOH and H2O2. The results show the generality of isatin oxidation method for preparing anthranilic acids, since the isatin used as substrate may contain different substituents on the nitrogen atom or aromatic ring. This methodology offers the possibility to prepare N-substituted anthranilic acids via simple alkylation and N-acylation reactions. Furthermore, all the products are obtained in short reaction times without catalysts and using aqueous basic solutions, featuring an environmentally friendly method.

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5 - Paleolimnological inferences based on Oligocene ostracods (Crustacea: Ostracoda) from Tremembé Formation, Southeast Brazil

Authors: Cristianini T. Bergue, Maria da Saudade A.S. Maranhão and Gerson Fauth

This work presents the first taxonomic and paleoecological study on ostracods from the Oligocene non-marine deposits of Tremembé Formation (Taubaté Basin, state of São Paulo, Brazil). It reveals rich assemblages composed of many new taxa, two of them herein described: Limnocythere mandubi sp. nov. and Limnocythere katu sp. nov. It is assumed that the associations recorded along the studied core represent different ecological phases of the paleolake Taubaté, which are discussed according to the taxonomic composition and preservational characteristics. The results from this pioneering study reinforce the potential of ostracods for paleolimnological researches in Brazilian Cenozoic deposits.

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6 - Estimating of gross primary production in an Amazon-Cerrado transitional forest using MODIS and Landsat imagery

Authors: Victor H.M. Danelichen, Marcelo S. Biudes, Maísa C.S. Velasque, Nadja G. Machado, Raphael S.R. Gomes, George L. Vourlitis and José S. Nogueira

The gross primary production (GPP) provides important information about accumulate biomass. Most of the GPP remote sensing models were developed using Moderate Resolution Imaging Spectroradiometer (MODIS) products. However, Landsat has the advantage of higher spatial resolution than MODIS. Given the need for further clarification of the potential of Landsat 5 TM, we evaluate GPP estimates of an Amazon-Cerrado Transitional Forest in Brazil using MODIS and Landsat 5 TM in this paper. The results indicated high potential of the Landsat 5 TM images to estimate the GPP of Amazon-Cerrado Transitional Forest.

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7 - Biochronostratigraphy and paleoenvironment analysis of neogene deposits from the Pelotas Basin (well 2-TG-96-RS), Southernmost Brazil

Authors: Wagner G. Silva, Geise S.A. Zerfass, Paulo A. Souza and Javier Helenes

Micropaleontological (palynology and foraminifera) and isotopic (87Sr/86Sr) data from the well 2-TG-96-RS, of the Pelotas Basin. Furnishes a Late Miocene (Messinian) age for the interval (6.05 Ma). Quantitative distribution of organic components and calcareous foraminifera throughout the section associations indicate a shallow marine depositional environment, with minor variations in the relative abundance of certain particulate organic matter and palynomorph groups linked to sea-level changes.

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8 - Santonian dinocyst assemblages of the Santa Marta Formation, Antarctic Peninsula: Inferences for paleoenvironments and paleoecology

Authors: Susan P. Castro and Marcelo A. Carvalho

Dinoflagelates cysts (dinocysts) from the deposits of the Santa Marta Formation, Antarctic, provided important information about the paleoenvironment changes and age. A lower-middle Santonian age was determined after the recognition of Odontochitina porifera and Isabelidinium cretaceum zones. Five dinocyst assemblages were recorded: Manumiella, Heterosphaeridium, Chlamydophorella, Isabelidinium and Odontochitina. A stratigraphical alternation between the assemblages distinguished six intervals. The marine paleoenvironments ranged from shallower setting (Manumiella assemblage), at the uppermost of the section, and deeper setting (Odontochitina assemblage) at the middle part. Two dinocyst blooms, Isabelidinium and Odontochitina, are recorded in the studied section, and for the first time correlated with other regions.

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9 - Eggshell and Histology Provide Insight on the Life History of a Pterosaur with Two Functional Ovaries

Authors: Xiaolin Wang, Alexander W.A. Kellner, Xin Cheng, Shunxing Jiang, Qiang Wang, Juliana M. Sayão, Taissa Rodrigues, Fabiana R. Costa, Ning Li, Xi Meng and Zhonghe Zhou

One of the many open biological questions regarding pterosaurs - the first vertebrates to conquer the air - is about their reproductive strategy. Here we report the counterpart of a previously described specimen that shows the presence of two eggs, one still inside the body cavity. This gravid female clearly had two functional oviducts and demonstrates that the reduction of one oviduct was not paramount for the evolution of powered flight. Histological section did not reveal any medullary bone, that has been reported in gravid birds. This information suggests that pterosaurs had a more basal reptilian reproductive strategy.

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10 - Zircon ages delimit the provenance of a sand extrudite from the Botucatu Formation in the Paraná volcanic province, Iraí, Brazil

Authors: Viter M. Pinto, Léo A. Hartmann, João O.S. Santos and Neal J. McNaughton

The historical observation of the presence of numerous sand layers at the contact of basalt flows in the Cretaceous (135 Ma) Paraná volcanic province (approximately 1,000,000 km2) is now understood. The wind-blown quartz (some feldspar) originated by fluidization and injection from the underlying Botucatu desert. We determined a large number (n = 102) of U-Pb ages of detrital zircon from one sand layer near Iraí, Rio Grande do Sul, Brazil, using the sensitive high-resolution ion microprobe (SHRIMP). The results are most significant, because the obtained ages constitute peaks at 2.8-2.6, 2.0-1.7 Ga and 1155-962, 808-500, 480-450 and 296-250 Ma. The sand layer originated by fluidization and injection into the basalts of loose erg sand from the underlying Botucatu desert.

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11 - Environmental changes during the last millennium based on multi-proxy palaeoecological records in savanna-forest mosaic from the northernmost Brazilian Amazon region

Authors: Maria Ecilene N.S. Meneses, Marcondes L. Costa, Dirk Enters and Hermann Behling

The dynamics of the savanna-forest mosaic over the last 1050 years have been reconstructed by palynological, mineralogical and geochemical analyses of sediment cores taken from Mauritia flexuosa palm swamps in the northern state of Roraima. This study showed wet climatic conditions during the recorded period. However, fires were frequent and partly explain the dominance of grassy savanna in this area. These fires were likely caused by human activities and as nowadays also hinder forest expansion into savanna areas. Besides sandy hydromorphic soils may act as an edaphic control to maintain the current sharp boundary between forest and savanna ecosystems.

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12 - Structural Properties of the Brazilian Air Transportation Network

Authors: Guilherme S. Couto, Ana Paula Couto da Silva, Linnyer B. Ruiz and Fabrício Benevenuto

The air transportation network in a country has impact on the local, national and global economy. In this work, we analyze the topological characteristics of the Brazilian air transportation network, based on the set of national and international flights operated by the Brazilian airports. Interesting conclusions emerge from our analysis. The main airports in the Brazilian infrastructure are the Viracopos and Guarulhos airports. Travelers need, on average, 3 connection flights to reach their destinations. We perform the resiliency analysis of the network robustness under topology changes: Viracopos Airport outage breaks the network into 6 subnetworks, affecting 10% of the passengers.

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13 - Anesthetic activity and bio-guided fractionation of the essential oil of Aloysia gratissima (Gillies & Hook.) Tronc. in silver catfish Rhamdia quelen

Authors: Simone C. Bevonit, Lenise L. Silva, Joseânia Salbergo, Vania L. Loro, Carlos A. Mallmann, Bernardo Baldisserotto, Erico M.M. Flores and Berta M. Heinzmann

This work describes the anesthetic activity of essential oil of Aloysia gratissima and its isolated compounds (E-(-)-pinocamphone, (-)-caryophyllene oxide, (-)-guaiol and (+)-spathulenol) in silver catfish. Essential oil of A. gratissima promoted anesthesia at concentrations of 300 to 900 mg L-1, however, fish presented involuntary muscle contractions. This side effect may be related to the presence of E-(-)-pinocamphone. (-)-Caryophyllene oxide, (-)-guaiol and (+)-spathulenol showed sedative effects, additionally, (+)-spathulenol (51.2 mg L-1) promoted anesthesia without side effects. Therefore, (+)-spathulenol showed potent sedative and anesthetic activities in silver catfish, and could be considered as a viable compound for the development of a new anesthetic.

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14 - The length of the dry season may be associated with leaf scleromorphism in cerrado plants

Authors: Marcelo C. Souza, Augusto C. Franco, Mundayatan Haridasan, Davi R. Rossatto, Janaína F. de Araújo, Leonor P.C. Morellato and Gustavo Habermann

The variations between sclerophyllous and less sclerophyllous leaves seem to respond to environmental factors. We propose that less sclerophyllous leaves found on the periphery of the Cerrado domain are associated with the shorter dry season in comparison to the core of this domain, where a longer dry season occurs. We measured the length of the dry season, soil fertility, leaf concentration of macronutrients, and the specific leaf area (SLA). Low SLA is found in sclerophyllous leaves, while high values typify less sclerophyllous leaves. On the periphery, the soil was more fertile, and higher SLA was accompanied by higher leaf nutrition.

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15 - A comparative study of nutritional composition and potential use of some underutilized tropical fruits of Arecaceae

Authors: Raquel B. Silva, Edvaldo V. Silva-Júnior, Laís C. Rodrigues, Laise H.C. Andrade, Suzene I. da Silva, Wolfgang Harand and Antonio F.M. Oliveira

The goal of our study was to perform a chemical analysis of the fruits of six tropical Arecaceae species, some of which have not been reported to date, to evaluate their potential use as food and for other industrial purposes. Three native species (Acrocomia intumescens, Syagrus coronata, and S. cearensis) are good sources of fresh food as well as excellent sources of carotenoids underutilized. Fruits of A. intumescens also could be a good alternative feedstock for soap and biodiesel production for the underserved populations that inhabit poorly developed areas such as the semi-arid region of Brazil.

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16 - Initial development of the endocarp in Lithraea brasiliensis Marchand (Anacardiaceae): with taxonomic notes

Authors: João M.S. de Oliveira and Jorge. E.A. Mariath

A detailed analysis of the endocarp formation in Lithraea brasiliensis along with a comparison to L. molleoides led to some important considerations. In this study, it was shown that the endocarp in Lithraea brasiliensis possesses only three layers and that the crystal layer is the innermost layer of the mesocarp. Considering that the endocarp differs from L. molleoides, it can be concluded that a taxonomic application of this structural characteristic across species of the same genus is possible.

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17 - Monitoring studies should consider temporal variability to reveal relations between cyanobacterial abundance and environmental variables

Authors: Juliana Wojciechowski and André A. Padial

Predictors of cyanobacterial blooms are usually investigated by sampling cyanobacteria and environmental variables simultaneously. The implicit assumption is that one snapshot sample is a good representation of environmental conditions in a location relative to others. We argue that this strategy can hide the predictors of cyanobacterial blooms. We used a 4-years dataset of several reservoirs for water supply in South Brazil and our results are conclusive for different analytical approaches commonly used to relate cyanobacteria and environmental predictors. We concluded that stronger environment-cyanobacteria relationships are found when the temporal variation of environmental variables and cyanobacterial abundance are used in analyses.

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18 - Reproductive morphology of female Guiana dolphins (Sotalia guianensis)

Authors: Estella Z. Becegato, Janaina P. Andrade, Juliana P. Guimarães, Jociery E. Vergara-Parente, Maria Angelica Miglino and Fernanda M. de Oliveira e Silva

In northeastern Brazil, although there is a large number of cetaceans’ strandings, reproductive morphology data are scarce. This study described histological characteristics of the female genital tract of Sotalia guianensis of different ages. Histological analyses showed that these structures were similar to those found in terrestrial mammals, with some peculiarities, such as the presence of differentiated cells in the vulvar subepidermal layer, not previously described for cetaceans. Reproductive studies with a morphological description of the female genital organs enable a better understanding of the species reproductive physiology and assist in the development of new strategies for the species conservation.

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19 - Bacterial and Archaeal Communities Variability Assotiated with Upwelling and Anthropogenic Pressures in the Protection Area of Arraial do Cabo (Cabo Frio region - RJ)

Authors: Sergio A. Coelho-Souza, Fábio V. Araújo, Juliano C. Cury, Hugo E. Jesus, Gilberto C. Pereira, Jean R.D. Guimarães, Raquel S. Peixoto, Alberto M.R. Dávila and Alexandre S. Rosado

Arraial do Cabo (RJ) is where upwelling occurs more intensively on the Brazilian coast. It is  very dynamic and holds high biodiversity and productivity. It is a protected area but an intense anthropogenic impact is observed mainly in function of harbor practices and untreated sewage disposal. Both impacts occur in the same embayment decreasing microbial diversity but increasing heterotrophic productivity. This productivity is associated with Bacteria and Archaea and despite anthropogenic pressure change their genetic composition, it is more extensive when upwelling is intense inputting microorganisms from deep waters in the impacted area that changes the nutrients cycling.

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20 - Linking environmental drivers with amphibian species diversity in ponds from subtropical grasslands

Authors: Darlene S. Gonçalves, Lucas B. Crivellari and Carlos Eduardo Conte

We examine which characteristics in breeding sites are most relevant in their influence on anuran diversity in grasslands with scattered forest fragments in subtropical, southern Brazil. We observed that deeper water bodies, which have larger pond surface area and shorter distance to the nearest forest fragment are the environments sheltering the highest diversity. Water depth, margin vegetation type, surface area and distance to the next body of water favors abundance of nine species. Thus, preservation of vegetation along the water edge and natural forest fragments in the grasslands, along with fire control, are fundamentally important for the stability of anuran species diversity through the maintenance and conservation of their breeding sites.

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21 - Abdominal macrochaetae of female Hylesia oratex Dyar, 1913 (Insecta: Lepidoptera: Saturniidae): external morphology and medical significance

Authors: Rosângela Brito, Alexandre Specht, Wilson S.A. Filho, Edegar Fronza and Carlos G.C. Mielke

Hylesia Hübner [1820] is significant among medically important Lepidoptera. Females use abdominal setae to wrap and protect the eggs, those when in contact with human skin may cause allergic reactions. The morphology of abdominal scales and setae from female H. oratex Dyar, 1913 is described. Two types of setae with medical importance classified as "true setae" and "modified setae" were found. The true setae are responsible for the allergic reactions caused by skin penetration and the modified setae could be responsible for the release of chemical substances. This information elucidates the urticating setae morphology, contributing to the identification of the moths.

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22 - Antioxidant status in women with uterine leiomyoma: relation with sex hormones

Authors: Snežana Pejić, Ana Todorović, Vesna Stojiljković, Ljubica Gavrilović, Nataša Popović and Snežana B. Pajović

Leiomyomas (myomas, fibroids) are benign tumors of the uterus. Their growth is considered to be influenced by some hormones. In this study we investigated the relation of gonadotropins and steroid hormones with antioxidant status in women diagnosed with uterine leiomyoma. The results suggest that some antioxidant enzymes activities in blood and leiomyoma tissue are related with sex hormones level.

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23 - Correlation between radiation dose and p53 protein expression levels in human lymphocytes

Authors: Mariana B. Cavalcanti, Thiago S. Fernandes, Edvane B. Silva and Ademir Amaral

This research investigated the relationship between dose and the p53 expression levels, and this protein’s potential as biomarker of individual exposure to ionizing radiation. Based on flow cytometric analyses of in vitro peripheral blood, the proposed methodology opens the possibility for evaluating individual radiosensitivity level and for fast screening of a large population suspected of having received overdoses in radiation incidents. The paper also discusses the employment of the technique in biomonitoring programs of occupational personnel who are systematically exposed to chronic low radiation doses. The results in this work may represent a step forward in biological assessments of individual exposures.

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24 - Counteracting effects on free radicals and histological alterations induced by a fraction with casearins

Authors: Éverton José Ferreira de Araújo, Guilherme Antônio Lopes de Oliveira, Lívia Queiroz de Sousa, Vanderlan da Silva Bolzani, Alberto José Cavalheiro, Adriana da Rocha Tome, Ana Paula Peron, André Gonzaga dos Santos, Antonia Maria das Graças Lopes Citó, Cláudia Pessoa, Rivelilson Mendes de Freitas and Paulo Michel Pinheiro Ferreira

Casearia sylvestris is a plant with medicinal properties that is popularly used to treat snakebites, wounds, diarrhea, flu and chest colds. The present study evaluates the antioxidant activities of a fraction with casearins (FC) isolated from C. sylvestris and histological changes on the central nervous system and livers of Mus musculus mice.

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25 - Neurotrophins, cytokines, oxidative parameters and functionality in Progressive Muscular Dystrophies

Authors: Clarissa M. Comim, Gisiane B. Mathia, Andreza Hoepers, Lisiane Tuon, Flávio Kapczinski, Felipe Dal-Pizzol, João Quevedo and Maria I. Rosa

We investigated the levels of brain derived-neurotrophic factor (BDNF), cytokines and oxidative parameters in serum and tried to correlate them with the age and functionality of patients with Progressive Muscle Dystrophies (PMD). DMD patients had a decrease of functionality, an increase in the IL-1β and TNF-α levels and a decrease of IL-10 levels and superoxide dismutase activity in serum. SMD patients had a decrease of BDNF and IL-10 levels and superoxide dismutase activity and an increase of IL-1β levels in serum. LGMD2A patients had a decrease only in serum levels of IL-10. 

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26 - Prevalence of Candida tropicalis and Candida krusei in onychomycosis in João Pessoa, Paraíba, Brazil from 1999 to 2010

Authors: Juliana M.M. Arruda, Luis A.S. Rodrigues, Fillipe O. Pereira and Edeltrudes O. Lima

This study carried out in João Pessoa-Paraíba contributes to research on epidemiology of fungal infections in humans. We reported that Candida species have emerged as important etiological agents of onychomycosis in adult women, from 1999 to 2010. The prevalent yeasts were Candida tropicalis and C. krusei. Our results show the importance of such infections caused by non-Iyeasts. Thus, this study provides data revealing changes in onychomycosis’s epidemiological patterns and etiology possibly useful both for diagnosis and treatment.

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27 - Physicochemical, in vitro and in vivo evaluation of flurbiprofen microemulsion

Authors: Muhammad Naeem, Nisar Ur Rahman, Guilherme D. Tavares, Sávio F. Barbosa, Nádia B. Chacra, Raimar Löbenberg and Muhammad K. Sarfraz

Flurbiprofen, a potent anti-inflammatory drug, is widely used for the relief of pain in patients suffering from rheumatic diseases. This drug has many gastrointestinal side effects produced by its oral administration such as gastric bleeding and peptic ulcer. We formulated and characterized gel based microemulsions, for topical delivery of flurbiprofen. Two gel bases namely Xanthan and Carbopol containing microemulsion and hydro-alcoholic solution of flurbiprofen were developed and compared. In vitro study showed that gels containing microemulsion (Carbopol-I) had a higher permeation rate. Carbopol-I showed higher percent of inhibition of inflammation. Further, it was found to be non-irritating to the human skin. 

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28 - Ground level photosynthetically active radiation dynamics in stands of Acacia mearnsii De Wild

Authors: Sylvio Péllico Netto, Carlos R. Sanquetta, Braulio O. Caron, Alexandre Behling, Augusto A. Simon, Ana Paula D. Corte and Rogério Bamberg

The study aimed at diagnosing the incidence of photosynthetically active radiation at the soil level along the black wattle crop cycle in Rio Grande do Sul, Brazil, to evaluate if the light incidence affects the initial growth of tree heights. By evaluation of the photosynthesis reduction in forest stands, it was possible to detect the inflexion point and the maximum height on the early acceleration process of their growth (3 years). This modeling process favors the monitoring of the most important variable on production prognosis in black wattle plantations for forest management purposes.

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29 - Effects of hormonal priming on seed germination of pigeon pea under cadmium stress

Authors: Larissa C. Sneideris, Marina A. Gavassi, Marcelo L. Campos, Victor D`Amico-Damião and Rogério F. Carvalho

Cadmium (Cd) is a widespread environmental contaminant that can adversely affect plant growth and productivity. We here evaluated if hormonal seed priming could improve the germination of pigeon pea (Cajanus cajan) under high concentrations of Cd. Among many different molecules tested, we found that pigeon pea seeds pre-treated with chloroethylphosphonic acid (which is rapidly metabolized and converted to the plant regulator ethylene) showed improved germination in media containing Cd when compared to mock-treated ones. This result suggests that ethylene seed priming may be a valuable strategy to improve germination in Cd-contaminated agricultural fields.

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30 - Evaluation of protein extraction methods for enhanced proteomic analysis of tomato leaves and roots

Authors: Milca B. Vilhena. Mônica R. Franco, Daiana Schmidt, Giselle Carvalho and Ricardo A. Azevedo

Proteomics is an outstanding area in science whose increasing application has advanced to a number of distinct purposes. The amount of fresh tissue to be used depends on the type of experiment to be carried out and may be a major obstacle in the reproducibility of a proteomic analysis. This work compared several protocols and developed a standardized 2-DE protocol to obtain accurate protein maps for tomato leaves and roots, starting from a minimum amount of plant tissue sufficient to perform gels in triplicates or quadruplicates, in association with a relatively simple method of extraction.

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31 - Mixed thermal convection: fundamental issues and analysis of the planar case

Authors: Jacques Padet, Renato M. Cotta, Emilia C. Mladin and Colette Padet

In most of the works on convective heat transfer, the mixed convection is shortly treated relative to the forced, natural, phase change convection modes; or simply omitted, related to the fact that mixed convection is a complex subject for which many elements are missing for a general and coherent approach. This paper aims to place the mixed thermal convection again in the centre of the convection heat transfer and to emphasize three issues that arise by this approach.

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32 - A science framework (SF) for agricultural sustainability

Authors: Ferdous Ahmed, Abul Q. Al-Amin, Muhammad M. Masud, Fatimah Kari and Zeeda Mohamad

The significance of Science Framework (SF) to date is receiving more acceptances all over the world to address agricultural sustainability. Specially, MSF in transitional economies is mostly incapable to identify barriers in agricultural research, inadequate to frame policy gaps with the goal of strategizing the desired sustainability in agricultural technology and innovation, inconsistent in finding to identify the inequities, and incompleteness to rebuild decisions. Therefore, this study critically evaluates the components of MSF in transitional economies and appraises the significance, dispute and illegitimate issue to achieve successful sustainable development through agricultural sustainability.

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