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Annals of the Brazilian Academy of SciencesAABC - Volume 85 (4) - December 2013 |
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With the present issue, the Annals of the Brazilian Academy of Sciences (Anais da Academia Brasileira de Ciências - AABC) published during the last year a total of 140 papers (and 4 editorials) in 1624 pages, the largest volume so far. There are several interesting highlights, such as the study of a potential larvicidal against Aedes aegypti, the main vector of the tropical disease, known as “dengue”, that over the last year is spreading in several contries. Other interesting papers deal with the antioxidant activity of four varieties of coconut water, a study trying to show ways in how oil palm plantations might be expanded, and different means on how to assess rainfall erosivity. Also worth pointing out are contributions that assess specific anthropomorphic influence on environment in distinct areas of Brazil, such as the human exposure to manganese in the South, the heavy metal flux in the Guanabara Bay, and the understanding of the heavy metals partitioning in the Rodrigo de Freitas lagoon (Rio de Janeiro). A paper on the perception of the advantages regarding using wild dolphins as tourist attractions, a controversial subject, was also published here. Moreover, this volume shows several other articles on different topics that might interest you. Please keep in mind that since 2000 all papers published by the AABC can be downloaded free of charge at the SCIELO site. 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
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● The Gauss Map of Complete Minimal Surfaces with Finite Total Curvature(Pedro A. Hinojosa, Gilvaneide N. Silva) In this paper we are concerned with the image of the normal Gauss map of a minimal surface immersed in the 3-euclidean space with finite total curvature. We give a different proof of the following theorem of R. Osserman: The normal Gauss map of a minimal surface immersed in 3-euclidean space R3, with finite total curvature, which is not a plane, omits at most three points of S2, the 2-sphere in R3. Moreover, under an additional hypothesis on the type of ends, we prove that this number is exactly 2. Read here |
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● Chemical study and larvicidal activity against Aedes aegypti of essential oil of Piper aduncum L. (Piperaceae)(Gisele L. Oliveira, Sheila K. Cardoso, Célio R. Lara Júnior, Thallyta M. Vieira, Elsie F. Guimarães, Lourdes S. Figueiredo, Ernane R. Martins, Davyson L. Moreira, Maria Auxiliadora C. Kaplan) Piper aduncum L. is used in folk medicine to treat respiratory and inflammatory diseases. The aim of this study was to analyze the essential oil from leaves of P. aduncum collected in the Brazilian Cerrado, North of Minas Gerais, as well as to evaluate the larvicidal activity of this oil and of its major constituent. The essential oil was analyzed by gas chromatography coupled to flame ionization detector and gas chromatography coupled to mass spectrometry that allowed characterizing 23 compounds (monoterpenes: 90.4%; sesquiterpenes: 7.0%). The major component was 1,8-cineole (53.9%). This oil showed to be very different from those obtained Read here |
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● Evaluation of Chemical Constituents and Antioxidant Activity of Coconut Water (Cocus nucifera L.) and Caffeic Acid in Cell Culture(João L.A. Santos, Vanderson S. Bispo, Adriano B.C. Filho, Isabella F.D. Pinto, Lucas S. Dantas, Daiane F. Vasconcelos, Fabíula F. Abreu, Danilo A. Melo, Isaac A. Matos, Florêncio P. Freitas, Osmar F. Gomes, Marisa H.G. Medeiros, Humberto R. Matos) In this article we evaluated the antioxidant activity of four varieties of coconut water - dwarf green, yellow Malaysian, red and yellow - through NO scavenging, DPPH, TBARS and DFC-DA assays. In addition, we compared the water with industrialized one and lyophilized green dwarf's water. All varieties presented antioxidant potential. The green dwarf coconut showed the highest antioxidant potential. Here, we identified and quantified caffeic acid through HPLC-MS-MS, we quantified vitamin C by colorimetric assay, and we extracted and quantified phenolic compounds. In IMR90 human lung fibroblast cell culture, green dwarf’s coconut water was efficient in protecting hydrogen peroxide-mediated oxidative damages. Read here |
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● Chemical constituents of Aspergillus sp. EJC08 isolated as endophyte from Bauhinia guianensis and their antimicrobial activity(Eduardo A.A. Pinheiro, Josiwander M. Carvalho, Diellem C.P. dos Santos, André O. Feitosa, Patríca S.B. Marinho, Giselle Maria S.P. Guilhon, Lourivaldo S. Santos, Afonso L.D. de Souza, Andrey M.R. Marinho) The present work reports the isolation of five compounds from Aspergillus sp. EJC08 isolated as endophytic from Bauhinia guianensis, a tipical plant of the Amazon. The compounds ergosterol (1), ergosterol peroxide (2), mevalolactone (3), monomethylsulochrin (4) and trypacidin A (5) were isolated by chromatographic Read here |
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● Evaluation of morpho-anatomical and chemical differences between varieties of the medicinal plant Casearia sylvestris Swartz(Josiane C. Claudino, Luis V.S. do Sacramento, Ingrid Koch, Helen A. Santos, Alberto J. Cavalheiro, Aristeu G. Tininis, André G. dos Santos) |
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● Evaluation of the Photodynamic Activity of Xanthene Dyes on Artemia salina described by Chemometric Approaches(Diogo S. Pellosi, Vagner R. Batislela, Vagner R. de Souza, Ieda S. Scarminio, Wilker Caetano, Noboru Hioka) It is important to develop new bioassay methods for photodynamic therapy (PDT) due
to its growing use in medical applications. Xanthene dyes irradiated with LED were investigated using Artemia salina as a bioindicator of photodynamic activity. A 23 full factorial design analysis was employed. The investigated factors were: (i) photosensitizers concentration, (ii) irradiation time and (iii) waiting time to begin the irradiation. The death of A. salina was related to dyes structures and the interaction between the irradiation time and the photosensitizers concentration. The proposed bioassay was found suitable for quantitative PDT evaluation. Read here |
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● Environmental pathways and human exposure to manganese in southern Brazil(Nadir Hermes, Rosana C.S. Schneider, Daniela D. Molin, Guilherme Z. Riegel, Adilson B. Costa, Valeriano A. Corbellini, João P.M. Torres, Olaf Malm) The study of environmental pathways and human exposure to Mn in southern Brazil was performed using two steps. The first step consisted of taking water samples from the surface of the Pardinho River. The average results from this technique showed a significant increase of pollutants, including increased levels of Mn, above the environmentally acceptable standard recommended. For the second step, soil samples were taken from areas with and without agricultural activity. Although the contamination appeared to come from a natural origin, the results found in the present study showed that the Mn levels present in the Basin are a relevant public health issue. Read here |
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● The Role of the Humic Substances in the Fractioning of Heavy Metals in Rodrigo de Freitas Lagoon, Rio de Janeiro - Brazil(Estefan M. da Fonseca, José A. Baptista Neto, John McAlister, Bernard Smith, Marcos A. Fernandez, Fabiano C. Balieiro) One of the main results of the processes related to urbanization is the contamination of the adjacent water bodies. Inserted in this context, the Rodrigo de Freitas lagoon is situated in the south zone of the city of Rio de Janeiro. This ecosystem receives several inputs containing all sorts of pollutants, including heavy metals. The present work aimed to study the partitioning of heavy metals in the sediments of Rodrigo de Freitas and the influence of organic matter in this fractionation dynamic. The results of these analyses presented the contents of organic matter as an important metal-capturing agent. Fractionation of organic matter resulted in a predominance of humine. Heavy metal partitioning showed that the metals bound by the water-soluble phase have no significant concentrations. Special features such as, reducing sediment, high levels of organic matter and fine grain size have transformed this ecosystem in an effective deposit of pollutants, where heavy metals are not available in easily reactive fractions. Read here |
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● Luminescence characteristisc of quartz from Brazilian sediments and constraints for OSL dating.(Carlos C.F. Guedes, André O. Sawakuchi, Paulo C.F. Giannini, Regina Dewitt, Vitor A.P. Aguiar) This study analyzes the optically stimulated luminescence (OSL) characteristics of quartz grains from fluvial, aeolian and shallow marine sands of northeastern and southeastern Brazil, with especial focus on the applicability of the single-aliquot regenerative dose (SAR) dating protocol. All analyzed Brazilian sediments presented relatively high OSL sensitivity and good behavior regarding their luminescence characteristics relevant for radiation dose estimation. However, we discussed the issues observed in some samples as inadequate OSL sensitivity correction and wide estimated dose distribution. Read here |
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● Geochronology and heavy metal flux to Guanabara Bay, Rio de Janeiro state: a preliminary study(José A Baptista Neto, Tomás C.S. Peixoto, Bernard J. Smith, John J. McAlister, Soraya M. Patchineelam, Sambasiva R. Patchineelam, Estefan M. Fonseca) Guanabara Bay, located in Rio de Janeiro state. It is surrounded by the second most important metropolitan area of the country. Over recent decades, land disturbance and urbanization in the surrounding area has significantly increased sediment input to the bay and had a negative effect on its overall environmental. This is especially related to high volumes of untreated sewage and industrial effluents. This study evaluates Read here |
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● Pollen grain morphology of Fabaceae in the Special Protection Area (SPA) Pau-de-Fruta, Diamantina, Minas Gerais, Brazil(Cynthia F.P. da Luz, Erica S. Maki, Ingrid Horák-Terra, Pablo Vidal-Torrado, Carlos Victor Mendonça Filho) Pollen morphology is a tool in several sciences, e.g., in the study of temporal development of the vegetation through pollen analysis of the soil. The results presented in this paper considered the pollen morphology of thirteen species belonging to seven genera of the Fabaceae family occurring in the Pau-de-Fruta Special Protection Area (SPA), Diamantina, State of Minas Gerais (Brazil). They serve as basis in geocronological and climatological research of the Cerrado, which currently are being developed in the study area. Read here |
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● Effect of environmental factors on the abundance of decapods crustaceans from soft bottoms off southeastern Brazil(Michele Furlan, Antonio L. Castilho, Lissandra C. Fernandes-Góes, Vivian Fransozo, Giovana Bertini, Rogério C. da Costa) The importance of environmental variables on the abundance patterns of decapods on the southeastern Brazilian coast is the central subject of this study. The results indicate that different factors may affect the abundance and distribution of decapod species, mainly sediment texture and water temperature. The study region, Ubatuba (23°S), is at the limit between two provinces, the Argentinian and the Brazilian, which include a mixture of species of both tropical and subantarctic origin. Thus, the species respond differently to environmental factors, mostly temperature, adjusting their distribution in space and time according to their intrinsic physiological limitations. Read here |
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● Spatial and Temporal Hydrochemical Variation of a Third Order River Network in a Quasi Pristine Coastal Waershed, at Southern Bahia, Brazil(Elly R.S. de Souza, Francisco C.F. de Paula) Preserved areas are suitable to define scientific paradigms, based on the background functioning of local ecosystems. The emerged scenario can be used for comparison purpose, related to disturbances induced by human activities, which bring changes in natural landscapes. A study was performed on the limnology of a well preserved watershed, focusing on the biogeochemistry dynamics of physical, chemical and biological proxies. The results show up the spatial and temporal behave of studied parameters, and represent the first attempt to define such behave at the Atlantic Rain Forest on the Northeastern Brazilian coast. Read here |
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● Transmission rate variation among three B chromosome variants in the fish Prochilodus lineatus (Characiformes, Prochilodontidae)(Manolo Penitente, Tatiana A. Voltolin, José A. Senhorini, Jehud Bortolozzi, Fausto Foresti, Fábio Porto-Foresti) Cytogenetic studies were developed in Prochilodus lineatus (Valenciennes 1836), describing an interesting system of small supernumerary chromosomes. The purpose of this work is to study the frequency and morphology of B chromosomes in individuals from the parental line and the inheritance patterns of these elements in individuals obtained from controlled crosses in the species P. lineatus. The transmission rate Read here |
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● Polychlorinated Biphenyl (PCB) congener concentrations in aquatic birds. Case study: Ilha Grande Bay, Rio de Janeiro, Brazil(Aldo Pacheco Ferreira) In research of polychlorinated biphenyl (PCB) congener concentrations (IUPAC numbers 8, 18, 28, 31, 52, 77, 101, 118, 126, 128, 138, 149, 153, 169, 170, and 180) in aquatic birds (Egretta caerulea (Linnaeus 1758), Nycticorax nycticorax (Linnaeus 1758), Egretta thula (Molina 1782), and Ardea cocoi (Linnaeus 1766)) from Ilha Grande Bay, Rio de Janeiro, Brazil, livers were collected from 108 birds found prostrate or dead in 2005 and 2010. Results indicate relatively low PCBs contamination in aquatic birds, but the close relationship of environmental contamination is implied, showing potential power of widespread biological and mutagenic adverse effects in trophic levels, and therefore, signaling risk to human health. Read here |
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● Morphology and anatomy of the diaspores and seedling of Paspalum (Poaceae, Poales)(Mayra T. Eichemberg, Vera L. Scatena) |
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● Responses of the molluscan fauna to environmental variations in a Halodule wrightii Ascherson ecosistema from Northeastern Brazil(Kcrishna V.S. Barros, Cristina A. Rocha-Barreira) This study observed the spatial and temporal distributions of molluscs in a Halodule wrightii meadow, verifying if they respond satisfactorily to seasonal changes in this seagrass ecosystem. The occurrence of some species in both strata or out of the expected stratum may have been influenced by shallow layer of the sediment considered, hydrodynamic, and low biomass of the studied meadow. However, the seagrasses had an important role on the seasonal and vertical variations of the molluscs, and the epiphyte Hypnea musciformis had a secondary role. The molluscs were sensible to environmental variations, and also reflected seasonal changes of the seagrass. Read here |
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● Horse spleen segmentation technique as large animal model of preclinical trials(Roberto P.P. Foz Filho, Benedito W. de Martins, Ana Rita de Lima, Maria Angélica Miglino) The parenchymal distribution of the splenic artery was studied in order to obtain anatomical basis for partial splenectomy. 26 spleens of healthy and adult horses and 6 spleens of fetus were studied. The spleens were submitted to arteriography in order to have their vascular pattern examined. The radiographic images were submitted to a measuring system for comparative analysis of areas of dorsal and ventral anatomo-surgical segments. Anatomical investigations into the angioarchitecture of the equine spleen showed a paucivascular area, allowing the organ to be divided in two anatomo-surgical segments of approximately 50% of the organ each. Read here |
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● Tryblionella persuadens comb. nov. (Bacillariaceae, Diatomeae): new observations on frustule morphology of a seldom recorded diatom(Kaoli P. Cavalcante, Priscila I. Tremarin, Eduardo G. Freire, Thelma A.V. Ludwig) The species Nitzschia persuadens Cholnoky, originally described from brackish waters of the Venetian Lagoon, is transferred to genus Tryblionella. It is a diatom rarely cited in the literature since its proposition and it is here recorded for the first time in a freshwater environment in South America. Here we present new observations on the frustule morphology in light and scanning electron microscopy and comparisons with related species. Read here |
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● Growth and biochemical composition of Chlorella vulgaris in different growth media(Mathias A. Chia, Ana T. Lombardi, Maria da Graça G. Melão) The need for clean and low-cost algae production demands for investigations on algal physiological response to different conditions. This study investigated the effect of different growth media (LC Oligo, Chu 10 and WC) on the growth, biomass production and biochemical composition of Chlorella vulgaris. WC medium performed poorly with regards to most of the parameters measured. The highest biomass production and specific growth rate were obtained in LC Oligo medium, while in terms of biochemical composition the Chu and LC oligo medium produced comparable results. LC Oligo was the most cost effective medium with best growth and biomass production. Read here |
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● Genetic variation in native and farmed populations to Tambaqui (Colossoma macropomum) in the Brazilian Amazon: regional discrepancies in farming systems(Jonas Aguiar, Horacio Schneider, Fátima Gomes, Jeferson Carneiro, Simôni Santos, Luis R. Rodrigues, Iracilda Sampaio) |
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● Reproductive phenology in a riparian rainforest in the south of Santa Catarina state, Brazil(Mainara F. Cascaes, Vanilde Citadini-Zanette, Birgit Harter-Marques) The reproductive phenology in a riparian rainforest was a study developed during one year that aimed to describe the reproductive phenophases of riparian plant species and correlate them with climatic variables. This paper presents significant contribution to the phenology knowledge in Brazil, specially to understand the reproductive phenology patterns in the South, since this area represents a gap inphenological studies. Therefore, studies that observe flowering and fruiting events in loco are of main importance because they provide information on reproductive seasons of species for use in environmental restoration projects and thus alleviate the situation of degradation of riparian forests. Read here |
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● Is the secondary thickening in palms always difuse?(Marli P. Botânico, Veronica Angyalossy) The secondary growth of palms has been described as diffuse, without the activity of a meristem. Some previous works of the early 20th century have mentioned the presence of a secondary meristem in the stems of palms, but this information was forgotten since then. We analyzed palm stems and found that a meristematic band occurs between the cortex and the central cylinder and gives rise to new vascular bundles and parenchyma internally, producing parenchyma and fibres externally. It appears secondarily, i.e., it undergoes meristematic activity in the median and basal stem regions, far away from the apical region. Read here |
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● Standardization of a method to study angiogenesis in a mouse model(David Feder, Fabio F. Perrazo, Edimar C. Pereira, Silvana Forsait, Cecília K.R. Feder, Paulo E.B. Junqueira, Virginia B.C. Junqueira, Ligia A. Azzalis, Fernando L.A. Fonseca) Angiogenesis is a physiological condition. But, uncontrolled angiogenesis have often been associated to angiogenesis-dependent pathologies. This work aimed to standardize a method for the study of angiogenesis and to investigate the effects of thalidomide on angiogenesis using sponges that were implanted in the back of mice. We could show that dosing hemoglobin from the implanted sponge it is possible to quantify the angiogenesis processes. Besides, we applied the new model for angiogenesis with thalidomide. Finally, in this article we presented that it is possible to apply this model with other drugs to study angiogenesis process. Read here |
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● Tau, APP, NCT and BACE1 in lymphocytes through cognitively normal ageing and neuropathology(Marisol Herrera-Rivero, Abraham Soto-Cid, María E. Hernandez, Gonzalo E. Aranda-Abreu) We analyzed the expression of APP, Nicastrin (NCT) and BACE1 by RT-PCR in lymphocytes from a small group of late-onset Alzheimer’s disease (AD) patients, aged patients suffering from neuropsychological conditions different from AD and cognitively healthy subjects divided into four groups by age (groups I-IV). We also investigated for correlations between expression and levels of blood pressure, glucose, cholesterol and triglycerides as risk factors for AD. NCT showed no expression in AD group and enhanced expression in NP group; NCT positively correlated with APP and BACE1 while blood pressure and cholesterol correlated with APP and NCT. Read here |
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● Evaluation of Bcl-2, Bcl-x and Cleaved Caspase-3 in Malignant Peripheral Nerve Sheath Tumors and Neurofibromas(Karen S. Cunha, Anabela C. Caruso, Paulo A. Faria, Licínio E. da Silva, Eliene C. da Fonseca, Mauro Geller, Rodrigo S. de Moura-Neto, Vânia S. Lopes) To study the expression of Bcl-2, Bcl-x, as well the presence of cleaved caspase-3 in neurofibromas and malignant peripheral nerve sheath tumors. The expression of Bcl-2 and Bcl-x and the presence of cleaved caspase-3 were compared to clinicopathological features of malignant peripheral nerve sheath tumors and their impact on survival rates were also investigated. The evaluation of Bcl-2, Bcl-x and cleaved caspase-3 was performed by immunohistochemistry using tissue microarrays in 28 malignant peripheral nerve sheath tumors and 38 neurofibromas. Immunoquantification was performed by computerized digital image analysis. Apoptosis is altered in neurofibromas and mainly in malignant peripheral nerve sheath tumors. High levels of cleaved caspase-3 are more common in tumors with more aggressive histological features and it is associated with lower disease free survival of patients with malignant peripheral nerve sheath tumors. Read here |
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● Nutritional parameters of steers receiving different levels of sunflower crushed in partial replacement of soybean meal(Hellen L. Lima, Rafael H.T.B. de Goes, Sara L.N. Cerilo, Euclides R. de Oliveira, Maria G.M. Gressler, Kelly C.S. Brabes) |
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● Assessing rainfall erosivity indices through synthetic precipitation series and artificial neural networks(Roberto A. Cecílio, Michel C. Moreira, José EduardoM. Pezzopane, Fernando F. Pruski, Danilo C. Fukunaga) This paper describes the use of synthetic rainfall series to compute the EI30 and the KE>25 rainfall erosivity indexes (R) in Espírito Santo State (Brazil). Artificial neural networks (ANNs) were also developed to spatially interpolate R values. EI30 and KE>25 indexes values were close to those calculated on a homogeneous area according to the similarity of rainfall distribution, indicating the applicability of the use of synthetic rainfall series to estimate the R factor. ANNs had a better performance than Inverse Distance Weighted and Kriging to spatially interpolate rainfall erosivity values in the State of Espírito Santo. Read here |
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● Centesimal composition and physical-chemistry analysis of the edible mushroom Lentinus strigosus occurring in the Brazilian Amazon(Ceci Sales-Campos, Lidia M. Araujo, Marli T.A. Minhoni, Meire C.N. Andrade) The centesimal composition and the physical and chemical analyses of Lentinus strigosus were evaluated. The substrates were formulated from Simarouba amara Aubl., Ochroma piramidale Cav. Ex. Lam. and Anacardium giganteum sawdust and Bactris gasipaes Kunth stipe and Saccharum officinarum. The nutritional composition of L. strigosus varied with the substrate of cultivation; the protein levels found in mushrooms grown in the different substrates varied with the substrate and was considered high. L. strigosus could be considered as important food owing to its nutritional characteristics such as high protein content, metabolizable carbohydrates and fibers, and low lipids and calories content. Read here |
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● Induction and characterization of oil palm (Elaeis guineensis Jacq.) pro-embryogenic masses(Marlúcia S. Pádua, Luciano V. Paiva, Cláudia R.G. Labory, Eduardo Alves, Vanessa C. Stein) Oil palm is one of the most economically valuable oil seed plants, but the expansion of plantations has been limited by availability of seedlings. One possible solution for the large-scale production is the use of somatic embryogenesis. The aim of this study was to evaluate the effects auxins 2.4-D and picloram on the induction of pro-embryogenic masses in E. guineenesis hybrid leaf explants and characterize, regarding embryogenic characteristics. Based on the anatomical and ultrastructural features, cell masses were considered to have the highest embryogenic potential and therefore may be most suited to large-scale vegetative propagation of oil palm. Read here |
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● Preliminary phytochemical screening and molluscicidal activity of the aqueous extract of Bidens pilosa Linné (Asteraceae) in Subulina octona (Mollusca, Subulinidade)(Bruna A. Souza, Lidiane C. Da Silva, Evelyn D. Chicarino, Elisabeth C.A. Bessa) Subulina octona is a land snail with medical and veterinary importance due to its participation as intermediate host in the life cycle of helminths. The aim of this study was to establish concentrations (LC50 e LC90) of aqueous extracts of Bidens pilosa in order to assess the changes caused by 24 and 48 h exposure to the sublethal concentration regarding species’ fecundity, hatchability and in offspring produced after exposure. The exposure to sublethal concentration reduced significantly the hatchability and the survival of the offspring hatched from exposed eggs and also caused a reduction on survival and growth in snails exposed. Read here |
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● Spatial and temporal analysis of stem bleeding disease in coconut palm in the state of Sergipe, Brazil(Rejane R. da Costa e Carvalho, Paulo E. de Souza, Dulce R.N. Warwick, Edson A. Pozza, José L.S. de Carvalho Filho) |
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● Perception of local inhabitants regarding the socioeconomic impact of tourism focused on provisioning wild dolphins in Novo Airão, Central Amazon, Brazil(Luis C.P.S. Alves, Camilah A. Zappes, Rafael G. Oliveira, Artur Andriolo, Alexandre de F. Azevedo) Botos (Inia geoffrensis) are currently provisioned for use in tourist attractions in five sites in Brazil. We present an evaluation of the perception of the local community concerning socioeconomic impacts of this tourism in Novo Airão, Amazonas State. In 2011, 45 inhabitants were interviewed. A small segment perceives currently itself as being economically dependent on this tourism, but the economic benefits are not shared among most inhabitants, and it is perceived as generating diverse negative effects. If it were banned or modified into a less impacting tourist activity, it would probably not majorly affect the lives of the general population. Read here |
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● E-commerce adoption in Malaysian Small and Medium Practitioner firms: A revisit on Roger`s model(Mehdi M. Poorangi, Edward W.S. Khin, Shohreh Nikoonejad, Arash Kardevani) The present study hinges upon exploring and explaining the different dimensions of the adoption of e-commerce among small and medium enterprises, based on the Five Factors of Diffusion of Innovation Model derived by Rogers. The results gleamed from this study posits that relative advantage is influential vis-à-vis e-commerce adoption. Trialability and Observability factors affect the level of confidence of management, which in turn, influences e-commerce adoption. Meanwhile, the existing culture of a company affects the resistance of employees, which in turn negatively affects the e-commerce adoption, while complexity does not significantly influence the e-commerce adoption. Read here |
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Annals of the Brazilian Academy of Sciences
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