for Journals by Title or ISSN
for Articles by Keywords
  Subjects -> BUSINESS AND ECONOMICS (Total: 3419 journals)
    - ACCOUNTING (106 journals)
    - BANKING AND FINANCE (292 journals)
    - BUSINESS AND ECONOMICS (1252 journals)
    - COOPERATIVES (4 journals)
    - ECONOMIC SCIENCES: GENERAL (191 journals)
    - HUMAN RESOURCES (97 journals)
    - INSURANCE (26 journals)
    - INTERNATIONAL COMMERCE (136 journals)
    - INVESTMENTS (22 journals)
    - MACROECONOMICS (17 journals)
    - MANAGEMENT (565 journals)
    - MARKETING AND PURCHASING (100 journals)
    - MICROECONOMICS (24 journals)
    - PUBLIC FINANCE, TAXATION (41 journals)

BUSINESS AND ECONOMICS (1252 journals)                  1 2 3 4 5 6 7 | Last

Showing 1 - 200 of 1566 Journals sorted alphabetically
4OR: A Quarterly Journal of Operations Research     Hybrid Journal   (Followers: 10)
Abacus     Hybrid Journal   (Followers: 16)
Accounting Forum     Hybrid Journal   (Followers: 27)
Acta Amazonica     Open Access   (Followers: 6)
Acta Commercii     Open Access   (Followers: 4)
Acta Oeconomica     Full-text available via subscription   (Followers: 3)
Acta Scientiarum. Human and Social Sciences     Open Access   (Followers: 8)
Acta Universitatis Danubius. Œconomica     Open Access   (Followers: 3)
Acta Universitatis Nicolai Copernici Zarządzanie     Open Access   (Followers: 4)
AD-minister     Open Access   (Followers: 3)
Adam Academy : Journal of Social Sciences / Adam Akademi : Sosyal Bilimler Dergisi     Open Access   (Followers: 2)
AdBispreneur : Jurnal Pemikiran dan Penelitian Administrasi Bisnis dan Kewirausahaan     Open Access  
Admisi dan Bisnis     Open Access  
ADR Bulletin     Open Access   (Followers: 6)
Advances in Developing Human Resources     Hybrid Journal   (Followers: 26)
Advances in Economics and Business     Open Access   (Followers: 15)
AfricaGrowth Agenda     Full-text available via subscription   (Followers: 2)
African Affairs     Hybrid Journal   (Followers: 65)
African Development Review     Hybrid Journal   (Followers: 37)
African Journal of Business and Economic Research     Full-text available via subscription   (Followers: 4)
African Journal of Business Ethics     Open Access   (Followers: 6)
African Review of Economics and Finance     Open Access   (Followers: 4)
Afro Eurasian Studies     Open Access  
Afro-Asian Journal of Finance and Accounting     Hybrid Journal   (Followers: 8)
Afyon Kocatepe Üniversitesi İktisadi ve İdari Bilimler Fakültesi Dergisi     Open Access   (Followers: 3)
Agronomy     Open Access   (Followers: 10)
Akademik Yaklaşımlar Dergisi     Open Access  
Akademika : Journal of Southeast Asia Social Sciences and Humanities     Open Access   (Followers: 7)
Alphanumeric Journal : The Journal of Operations Research, Statistics, Econometrics and Management Information Systems     Open Access   (Followers: 5)
American Economic Journal : Applied Economics     Full-text available via subscription   (Followers: 208)
American Enterprise Institute     Free  
American Journal of Business     Hybrid Journal   (Followers: 17)
American Journal of Business and Management     Open Access   (Followers: 55)
American Journal of Business Education     Open Access   (Followers: 12)
American Journal of Economics and Business Administration     Open Access   (Followers: 26)
American Journal of Economics and Sociology     Hybrid Journal   (Followers: 34)
American Journal of Evaluation     Hybrid Journal   (Followers: 15)
American Journal of Finance and Accounting     Hybrid Journal   (Followers: 22)
American Journal of Health Economics     Full-text available via subscription   (Followers: 12)
American Journal of Industrial and Business Management     Open Access   (Followers: 25)
American Journal of Medical Quality     Hybrid Journal   (Followers: 8)
American Law and Economics Review     Hybrid Journal   (Followers: 27)
ANALES de la Universidad Central del Ecuador     Open Access   (Followers: 3)
Ankara University SBF Journal     Open Access  
Annales de l'Institut Henri Poincare (C) Non Linear Analysis     Full-text available via subscription   (Followers: 1)
Annals in Social Responsibility     Full-text available via subscription  
Annals of Finance     Hybrid Journal   (Followers: 32)
Annals of Operations Research     Hybrid Journal   (Followers: 10)
Annual Review of Economics     Full-text available via subscription   (Followers: 38)
Anuario Facultad de Ciencias Económicas y Empresariales     Open Access   (Followers: 2)
Applied Developmental Science     Hybrid Journal   (Followers: 3)
Applied Economics     Hybrid Journal   (Followers: 44)
Applied Economics Letters     Hybrid Journal   (Followers: 30)
Applied Economics Quarterly     Full-text available via subscription   (Followers: 11)
Applied Financial Economics     Hybrid Journal   (Followers: 27)
Applied Mathematical Finance     Hybrid Journal   (Followers: 7)
Applied Stochastic Models in Business and Industry     Hybrid Journal   (Followers: 6)
Arab Economic and Business Journal     Open Access   (Followers: 4)
Archives of Business Research     Open Access   (Followers: 6)
Arena Journal     Full-text available via subscription   (Followers: 1)
Argomenti. Rivista di economia, cultura e ricerca sociale     Open Access   (Followers: 4)
ASEAN Economic Bulletin     Full-text available via subscription   (Followers: 6)
Asia Pacific Business Review     Hybrid Journal   (Followers: 8)
Asia Pacific Journal of Human Resources     Hybrid Journal   (Followers: 317)
Asia Pacific Journal of Innovation and Entrepreneurship     Open Access  
Asia Pacific Viewpoint     Hybrid Journal  
Asia-Pacific Journal of Business Administration     Hybrid Journal   (Followers: 5)
Asia-Pacific Journal of Operational Research     Hybrid Journal   (Followers: 3)
Asia-Pacific Management and Business Application     Open Access   (Followers: 1)
Asian Business Review     Open Access   (Followers: 3)
Asian Case Research Journal     Hybrid Journal   (Followers: 1)
Asian Development Review     Open Access   (Followers: 14)
Asian Economic Journal     Hybrid Journal   (Followers: 8)
Asian Economic Papers     Hybrid Journal   (Followers: 7)
Asian Economic Policy Review     Hybrid Journal   (Followers: 4)
Asian Journal of Accounting and Governance     Open Access   (Followers: 3)
Asian Journal of Business Ethics     Hybrid Journal   (Followers: 9)
Asian Journal of Social Sciences and Management Studies     Open Access   (Followers: 7)
Asian Journal of Sustainability and Social Responsibility     Open Access   (Followers: 2)
Asian Journal of Technology Innovation     Hybrid Journal   (Followers: 8)
Asian-pacific Economic Literature     Hybrid Journal   (Followers: 6)
AStA Wirtschafts- und Sozialstatistisches Archiv     Hybrid Journal   (Followers: 5)
ATA Journal of Legal Tax Research     Hybrid Journal   (Followers: 4)
Atlantic Economic Journal     Hybrid Journal   (Followers: 11)
Australasian Journal of Regional Studies, The     Full-text available via subscription   (Followers: 1)
Australian Cottongrower, The     Full-text available via subscription   (Followers: 1)
Australian Economic Papers     Hybrid Journal   (Followers: 35)
Australian Economic Review     Hybrid Journal   (Followers: 3)
Australian Journal of Maritime and Ocean Affairs     Hybrid Journal   (Followers: 9)
Balkan Region Conference on Engineering and Business Education     Open Access   (Followers: 1)
Baltic Journal of Real Estate Economics and Construction Management     Open Access   (Followers: 2)
Banks in Insurance Report     Hybrid Journal   (Followers: 1)
BBR - Brazilian Business Review     Open Access   (Followers: 4)
Benchmarking : An International Journal     Hybrid Journal   (Followers: 10)
Benefit : Jurnal Manajemen dan Bisnis     Open Access   (Followers: 1)
BER : Consumer Confidence Survey     Full-text available via subscription   (Followers: 3)
BER : Economic Prospects : An Executive Summary     Full-text available via subscription  
BER : Economic Prospects : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Intermediate Goods Industries Survey     Full-text available via subscription   (Followers: 1)
BER : Manufacturing Survey : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Motor Trade Survey     Full-text available via subscription  
BER : Retail Sector Survey     Full-text available via subscription   (Followers: 1)
BER : Retail Survey : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Survey of Business Conditions in Building and Construction : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Manufacturing : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Retail : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Trends : Full Survey     Full-text available via subscription   (Followers: 1)
BER : Wholesale Sector Survey     Full-text available via subscription  
Berkeley Business Law Journal     Free   (Followers: 9)
Beykent Üniversitesi Sosyal Bilimler Dergisi     Open Access  
Bio-based and Applied Economics     Open Access   (Followers: 1)
Biodegradation     Hybrid Journal   (Followers: 1)
Biology Direct     Open Access   (Followers: 7)
Bitlis Eren Üniversitesi İktisadi Ve İdari Bilimler Fakültesi Akademik İzdüşüm Dergisi     Full-text available via subscription  
BizInfo (Blace) Journal of Economics, Management and Informatics     Open Access  
Black Enterprise     Full-text available via subscription  
Board & Administrator for Administrators only     Hybrid Journal  
Boletim Técnico do Senac     Open Access  
Border Crossing : Transnational Working Papers     Open Access   (Followers: 4)
Briefings in Real Estate Finance     Hybrid Journal   (Followers: 5)
British Journal of Industrial Relations     Hybrid Journal   (Followers: 38)
Brookings Papers on Economic Activity     Open Access   (Followers: 50)
Brookings Trade Forum     Full-text available via subscription   (Followers: 3)
BRQ Business Research Quarterly     Open Access   (Followers: 2)
Building Sustainable Legacies : The New Frontier Of Societal Value Co-Creation     Full-text available via subscription   (Followers: 1)
Bulletin of Economic Research     Hybrid Journal   (Followers: 16)
Bulletin of Geography. Socio-economic Series     Open Access   (Followers: 5)
Bulletin of Indonesian Economic Studies     Hybrid Journal   (Followers: 4)
Bulletin of the Dnipropetrovsk University. Series : Management of Innovations     Open Access   (Followers: 1)
Business & Entrepreneurship Journal     Open Access   (Followers: 19)
Business & Information Systems Engineering     Hybrid Journal   (Followers: 6)
Business & Society     Hybrid Journal   (Followers: 10)
Business : Theory and Practice / Verslas : Teorija ir Praktika     Open Access   (Followers: 1)
Business and Economic Research     Open Access   (Followers: 7)
Business and Management Horizons     Open Access   (Followers: 12)
Business and Management Research     Open Access   (Followers: 20)
Business and Management Studies     Open Access   (Followers: 13)
Business and Professional Communication Quarterly     Hybrid Journal   (Followers: 7)
Business and Society Review     Hybrid Journal   (Followers: 6)
Business Economics     Hybrid Journal   (Followers: 15)
Business Ethics Quarterly     Full-text available via subscription   (Followers: 14)
Business Ethics: A European Review     Hybrid Journal   (Followers: 18)
Business Horizons     Hybrid Journal   (Followers: 9)
Business Information Review     Hybrid Journal   (Followers: 15)
Business Management and Strategy     Open Access   (Followers: 41)
Business Research     Hybrid Journal   (Followers: 3)
Business Strategy and the Environment     Hybrid Journal   (Followers: 13)
Business Strategy Review     Hybrid Journal   (Followers: 8)
Business Strategy Series     Hybrid Journal   (Followers: 6)
Business Systems & Economics     Open Access   (Followers: 2)
Business Systems Research Journal     Open Access   (Followers: 5)
Business, Economics and Management Research Journal : BEMAREJ     Open Access   (Followers: 1)
Business, Management and Education     Open Access   (Followers: 18)
Business, Peace and Sustainable Development     Full-text available via subscription   (Followers: 3)
Business: Theory and Practice     Open Access  
Bustan     Hybrid Journal  
Cadernos EBAPE.BR     Open Access   (Followers: 1)
Cambridge Journal of Economics     Hybrid Journal   (Followers: 65)
Cambridge Journal of Regions, Economy and Society     Hybrid Journal   (Followers: 11)
Canadian Journal of Administrative Sciences / Revue Canadienne des Sciences de l Administration     Hybrid Journal   (Followers: 1)
Canadian Journal of Economics/Revue Canadienne d`Economique     Hybrid Journal   (Followers: 35)
Canadian journal of nonprofit and social economy research     Open Access   (Followers: 3)
Capitalism Nature Socialism     Hybrid Journal   (Followers: 18)
Cappadocia Academic Review     Open Access  
Case Studies in Business and Management     Open Access   (Followers: 10)
CBU International Conference Proceedings     Open Access   (Followers: 3)
Central European Business Review     Open Access   (Followers: 1)
Central European Journal of Operations Research     Hybrid Journal   (Followers: 5)
Central European Journal of Public Policy     Open Access   (Followers: 2)
CESifo Economic Studies     Hybrid Journal   (Followers: 18)
Chain Reaction     Full-text available via subscription  
Challenge     Full-text available via subscription   (Followers: 4)
China & World Economy     Hybrid Journal   (Followers: 16)
China : An International Journal     Full-text available via subscription   (Followers: 18)
China Economic Journal: The Official Journal of the China Center for Economic Research (CCER) at Peking University     Hybrid Journal   (Followers: 12)
China Economic Review     Hybrid Journal   (Followers: 11)
China Finance Review International     Hybrid Journal   (Followers: 5)
China Nonprofit Review     Hybrid Journal   (Followers: 3)
China perspectives     Open Access   (Followers: 12)
Chinese Economy     Full-text available via subscription  
Ciência & Saúde Coletiva     Open Access   (Followers: 2)
Ciencia Sociales y Económicas     Open Access  
CLIO América     Open Access   (Followers: 1)
Cliometrica     Hybrid Journal   (Followers: 4)
COEPTUM     Open Access  
Community Development Journal     Hybrid Journal   (Followers: 28)
Compendium : Cuadernos de Economía y Administración     Open Access  
Compensation & Benefits Review     Hybrid Journal   (Followers: 7)
Competition & Change     Hybrid Journal   (Followers: 11)
Competitive Intelligence Review     Hybrid Journal   (Followers: 2)
Competitiveness Review : An International Business Journal incorporating Journal of Global Competitiveness     Hybrid Journal   (Followers: 5)
Computational Economics     Hybrid Journal   (Followers: 9)
Computational Mathematics and Modeling     Hybrid Journal   (Followers: 8)
Computer Law & Security Review     Hybrid Journal   (Followers: 17)
Computers & Operations Research     Hybrid Journal   (Followers: 12)
Construction Innovation: Information, Process, Management     Hybrid Journal   (Followers: 14)
Contemporary Wales     Full-text available via subscription   (Followers: 1)
Contributions to Political Economy     Hybrid Journal   (Followers: 5)
Corporate Communications An International Journal     Hybrid Journal   (Followers: 7)
Corporate Philanthropy Report     Hybrid Journal   (Followers: 3)

        1 2 3 4 5 6 7 | Last

Journal Cover
Acta Amazonica
Journal Prestige (SJR): 0.36
Citation Impact (citeScore): 1
Number of Followers: 6  

  This is an Open Access Journal Open Access journal
ISSN (Print) 0044-5967
Published by SciELO Homepage  [726 journals]
  • Relevance of wood anatomy and size of Amazonian trees in the determination
           and allometry of sapwood area

    • Abstract: ABSTRACT Hydrological processes in forest stands are mainly influenced by tree species composition and morpho-physiological characteristics. Few studies on anatomical patterns that govern plant hydraulics were conducted in tropical forest ecosystems. Thus, we used dye immersion to analyze sapwood area patterns of 34 trees belonging to 26 species from a terra firme forest in the central Brazilian Amazon. The sapwood area was related with wood anatomy and tree size parameters (diameter-at-breast-height - DBH, total height and estimated whole-tree volume). Exponential allometric equations were used to model sapwood area using the biometrical variables measured. Sapwood area traits (cross-section non-uniformity and heartwood visibility) varied significantly among and within species even though all were classified as diffuse porous. DBH was strongly and non-linearly correlated with sapwood area (R 2 = 0.46, P < 0.001), while no correlation was observed with vessel-lumen diameter (P = 0.94) and frequency (P = 0.58). Sapwood area and shape were also affected by the occurrence of vessel obstruction (i.e., tyloses), hollow stems and diseases. Our results suggest that sapwood area patterns and correlated variables are driven by intrinsic species characteristics, microclimate and ecological succession within the stand. We believe that individual tree sapwood characteristics have strong implications over water use, hydrological stand upsaling and biomass quantification. These characteristics should be taken into account (e.g., through a multi-point sampling approach) when estimating forest stand transpiration in a highly biodiverse ecosystem.RESUMO Processos hidrológicos de povoamentos florestais são predominantemente influenciados pela composição de espécies arbóreas e suas características morfo-fisiológicas. No entanto, existem poucos estudos sobre os padrões anatômicos que determinam o sistema hidráulico de plantas em ecossistemas tropicais. Por isso, nosso objetivo foi o de analisar os padrões da área do xilema ativo em 34 árvores de 26 espécies de uma floresta de terra firme na Amazônia central por meio de imersão em solução de corante. A área do xilema ativo foi relacionada a características autoecológicas das espécies, anatomia da madeira e parâmetros de crescimento (diametro à altura do peito - DAP, altura total e volume total). Equações alométricas exponenciais foram utilizadas para ajustar a área do xilema às variáveis medidas. Características do alburno (área transversal não-uniforme e visibilidade do cerne) variaram significativamente entre e dentro de espécies, apesar de que todas as espécies apresentaram vasos difusos. DAP foi fortemente e não-linearmente correlacionado à área do alburno (R 2 = 0,46; P < 0,001), enquanto diâmetro (P = 0,94) e frequência (P = 0.58) de vasos não apresentaram nenhum grau de relacionamento. O tamanho e forma do alburno foram afetados pela ocorrência de obstrução de poros (tilose) e troncos ocos. Estes padrões sugerem que a área do xilema é influenciada por características intrínsicas de cada espécie, microclima e estágio sucessional dentro do povoamento. Nossos resultados implicam que características individuais de árvores podem fortemente influenciar o transporte de água e, consequentemente, os processos hidrológicos e a quantificação de biomassa do povoamento. Essas caracteristicas deveriam ser consideradas (por exemplo, por meio da coleta de amostras da área do xilema ativo ao longo da área transversal) ao estimar-se a transpiração de uma floresta altamente biodiversa.
  • Feeding frequency affects feed intake and growth in juvenile pirarucu
           (Arapaima gigas)

    • Abstract: ABSTRACT Pirarucu is one of the main fish species for the development of aquaculture in the Amazon. In this study, the optimal feeding frequency for juvenile pirarucu was assessed based on growth and feed efficiency. Juvenile pirarucu weighing ca. 80 g were fed once, twice, three or four times daily until apparent satiation for 63 days. Fish fed three or four times per day presented higher growth, feed intake, and fat body content than those fed once or twice per day. There was no significant difference for feed conversion ratio, and protein and energy retention rates among treatments, suggesting that increased feeding frequency did not affect feed utilization efficiency. Mean feed intake per meal was higher when fish were fed once per day, possibly causing hyperphagic behavior. Results suggest that feeding three times per day was sufficient to secure adequate feeding and growth of juvenile pirarucu.RESUMO O pirarucu é uma das principais espécies de peixe para o desenvolvimento da aquicultura na região amazônica. Neste trabalho foi avaliada a frequência de alimentação ideal para juvenis de pirarucu com base em crescimento e eficiência alimentar. Juvenis de aproximadamente 80 g foram alimentados uma, duas, três ou quatro vezes ao dia até a saciedade aparente durante 63 dias. Maior crescimento, ingestão alimentar e gordura corporal foram observados nos peixes alimentados três ou quatro vezes ao dia em comparação com aqueles alimentados uma ou duas vezes ao dia. Não houve diferença significativa para as taxas de conversão alimentar, retenção proteica e retenção energética entre os tratamentos, indicando que o aumento da frequência de alimentação não resultou em prejuízo da eficiência de utilização do alimento. O consumo médio de alimento por refeição foi maior nos peixes alimentados apenas uma vez ao dia, que provavelmente desenvolveram comportamento hiperfágico. Os resultados sugerem que três refeições diárias foram suficientes para garantir o consumo de alimento e crescimento adequados nessa fase.
  • A new termite species of the genus Dihoplotermes Araújo (Blattaria,
           Isoptera, Termitidae) from the Brazilian Amazonian rainforest

    • Abstract: ABSTRACT Dihoplotermes, a previously monotypic genus, is now composed of two species. Dihoplotermes taurus sp. nov., a new Termitinae termite species, is illustrated and described based on morphological characters from soldiers, workers, and imago. The new species is distinguished from Dihoplotermes inusitatus Araujo by having a spine-like protuberance with blunt apex on the postmentum, the presence of a spine on the gizzard and the absence of dimorphic soldiers. Furthermore, the internal morphological characteristics of a Dihoplotermes worker are described for the first time. Both internal and external morphological characters were used to improve the characterization of the species.RESUMO Dihoplotermes, que era um gênero monotípico, agora é composto por duas espécies. Dihoplotermes taurus sp. nov., uma nova espécie de cupim Termitinae, é descrita e ilustrada com base nos caracteres morfológicos dos soldados, operários e imago. A nova espécie se diferencia de Dihoplotermes inusitatus Araujo por apresentar uma protuberância em forma de espinho não pontiagudo no posmento, presença de um espinho na moela e ausência de soldados dimórficos. Além disso, são descritas pela primeira vez as características morfológicas internas de um operário de Dihoplotermes e utilizamos ambos caracteres morfológicos internos e externos para melhor caracterizar as espécies.
  • Predation of an American fruit-eating bat (Artibeus sp.) by an Amazon tree
           boa (Corallus hortulanus) in the northern Brazilian Amazon

    • Abstract: ABSTRACT We report an observation of predation by an Amazon tree boa, Corallus hortulanus, on an American fruit-eating bat, Artibeus sp., in an area of seasonal forest close to a small stream in the northern Brazilian Amazon. While bats appear to be one of the main food items of C. hortulanus, our observation is only the fourth such event to be recorded in the Brazilian Amazon. The Artibeus sp. individual was observed making distress (agony) calls continuously over a period of three hours, much longer than recorded on previous observations. Records of this type are important to further our knowledge on bat predators, and the defensive behavior of bats.RESUMO Nós relatamos uma observação de predação por uma serpente Corallus hortulanus sobre um morcego do gênero Artibeus em uma área de floresta estacional perto de um córrego, no norte da Amazônia brasileira. Enquanto os morcegos parecem ser um dos principais itens alimentares de C. hortulanus, a nossa observação representa somente o quarto relato para a Amazônia brasileira. O indivíduo de Artibeus sp. foi observado vocalizando com chamados de distress (agonia) durante um período de três horas, o que representa uma duração muito maior do que o reportado em registros anteriores. Registros deste tipo são extremamente importantes para aumentar o nosso conhecimento sobre os predadores de morcegos e sobre o comportamento de defesa dos morcegos.
  • Foliar anatomy of Rhynchosia spp. (Leguminosae, Papilionoideae) from
           Roraima state, northern Brazilian Amazon

    • Abstract: ABSTRACT Comparative studies on the structure of foliar anatomy in four species of Rhynchosia from Roraima state (northern Brazilian Amazon) were carried out to identify additional morphological characters to support the definition of the systematic boundaries among the species. Fully expanded leaves, including the petioles, were collected from the upper nodes of a plant’s stem. Anatomical characters were observed in cross-sections of the middle portion of leaflets and petiole segments. Presence and distribution of glandular trichomes, continuity of sclerenchyma around the vascular bundles in leaflet blades and the conformation of the area between the two ridges of petioles were important characters to distinguish among the species of Rhynchosia. For the first time we report a distinct multicellular gland-like structure which we found in the petioles of three species.RESUMO Estudos comparativos da estrutura anatômica foliar foram realizados para identificar caracteres morfológicos adicionais para a caracterização sistemática de quatro espécies de Rhynchosia ocorrentes em Roraima. Folhas completamente expandidas, incluindo o pecíolo, foram coletadas nos nós superiores da planta. Os caracteres anatômicos foram estudados a partir de observações de cortes tranversais da região mediana de folíolos e pecíolos. A presença e a distribuição de tricomas glandulares, a continuidade do esclerênquima em torno dos feixes vasculares nos folíolos e a conformação da região entre as duas alas nos pecíolos se mostraram importantes caracteres para a distinção das espécies amazônicas de Rhynchosia. Também foi registrada pela primeira vez a ocorrência de uma diferenciada estrutura similar a glândula nos pecíolos de três espécies.
  • New records of three Neotropical arboreal ant species of Camponotus,
           subgenus Dendromyrmex (Hymenoptera: Formicidae) for the southern Amazon,
           including biological information

    • Abstract: ABSTRACT Camponotus (Formicinae) is the most specious and abundant genus of the family Formicidae. The genus is represented by ants that both forage and nest in the most diverse terrestrial and arboreal environments. Among the arboreal species of Camponotus are those of the subgenus Dendromyrmex. We recorded, for the first time, evidence of Camponotus chartifex (Smith, 1860) in the state of Mato Grosso, Brazil, and expanded the distributions of Camponotus nidulans (Smith, 1860) and Camponotus apicalis (Mann, 1916). We include information on the biology of the species and a discussion on the sampling of arboreal and winged ants.RESUMO Camponotus é um dos gêneros mais especiosos e abundantes da subfamília Formicidae. O gênero é representado por formigas que se alimentam e nidificam nos mais diversos habitats de ambientes terrestres e arbóreos. Entre as espécies arborícolas de Camponotus, estão as do subgênero Dendromyrmex. Registramos, pela primeira vez, Camponotus chartifex (Smith, 1860) para o estado de Mato Grosso, Brasil, e expandimos a distribuição de Camponotus nidulans (Smith, 1860) e Camponotus apicalis (Mann, 1916), incluindo informações biológicas sobre as espécies e uma discussão sobre a amostragem de formigas arborícolas e aladas.
  • Evaluation of the antioxidant potential of Copaifera multijuga in Ehrlich
           tumor-bearing mice

    • Abstract: ABSTRACT Copaifera multijuga, commonly known as copaiba, is popularly used in the form of tea for various conditions due to the presence of antioxidant substances in its composition, which protect cells against damage caused by free radicals. Its oleoresin is also used as an anti-inflammatory and antitumoral agent. The present study investigated the antioxidant effect of the ethanolic extract of copaiba stem bark on Swiss mice inoculated with solid Ehrlich tumors. Mice were inoculated subcutaneously with 1x106 Ehrlich’s tumor cells and treated via gavage with ethanolic extract of copaiba for thirty days, with doses varying between 100 and 200 mg kg-1. Biochemical analyses of enzymatic antioxidants [superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST)], non-enzymatic antioxidants [reduced glutathione (GSH) and ascorbic acid (ASA)], substances reactive to thiobarbituric acid (TBARS) and protein carbonylation (carbonyl) in different tissues were significantly affected. The extract administered at 200 mg kg-1 presented higher antioxidant capacity in the liver, increased CAT, GST, GSH and decreased TBARS, as well as increased CAT activity and protein carbonylation in brain tissue. The results showed that the copaiba extract was able to reverse the oxidative stress caused by solid Ehrlich tumor, probably due to the presence of antioxidant compounds, and had potential antineoplasic effect after a 30-day treatment.RESUMO Copaifera multijuga, ou copaíba, é utilizada popularmente como chá para o tratamento de diversas afecções, o que se deve à presença de substâncias antioxidantes em sua composição, que protegem as células contra danos causados pelos radicais livres. O óleo-resina da árvore é usado como antiinflamatório e antitumoral. O presente estudo avaliou o efeito antioxidante do extrato etanólico da casca da copaíba sobre camundongos Swiss machos inoculados com tumor sólido de Ehrlich. Os camundongos foram inoculados subcutaneamente com 1x106 células de tumor de Ehrlich e foram tratados, via gavagem durante 30 dias, com doses de extrato etanólico de copaíba variando de 100 a 200 mg kg-1. Realizou-se análise bioquímica dos antioxidantes enzimáticos [superóxido dismutase (SOD), catalase (CAT), glutationa-S-transferase (GST)], antioxidantes não-enzimáticos [glutationa reduzida (GSH) e ácido ascórbico (ASA)], substâncias reativas ao ácido tiobarbitúrico (TBARS) e carbonilação proteica (carbonil) em diferentes tecidos e apresentando resultados significativos. O extrato administrado na concentração de 200 mg kg-1 apresentou melhor capacidade antioxidante no fígado, aumentando a CAT, GST, GSH e diminuindo TBARS, além de aumentar a atividade da CAT e da carbonilação proteica no tecido cerebral. Os resultados mostram que o extrato de copaíba foi capaz de reverter o estresse oxidativo causado pelo tumor sólido de Ehrlich, provavelmente por conter compostos antioxidantes, e possivelmente teve um efeito antineoplásico após 30 dias de tratamento.
  • Phenolic compounds from Virola venosa (Myristicaceae) and evaluation of
           their antioxidant and enzyme inhibition potential

    • Abstract: ABSTRACT Virola venosa, popularly known in Brazil as ucuuba-da-mata, occurs naturally in the Amazon region and has potential to provide useful natural compounds, as already known for other Virola species. Therefore, the objective of this study was to determine the chemical composition of bark and leaf extracts of V. venosa, and to test the antioxidant capacity and α-glucosidase inhibition potential of their compounds. Polar extracts showed to be more active in both assays, therefore a bioactivity-guided fractionation was performed to identify the compounds that were responsible for the recorded activities. Using a combination of LC-MS/MS analysis and isolation with NMR identification, eight phenolic compounds were identified. Assays with pure compounds of the active fraction revealed that ferulic acid was the main contributor compound to the observed bioactivity in the crude extracts.Resumo Virola venosa, popularmente conhecida como ucuuba-da-mata, ocorre naturalmente na região amazônica e tem potencial para fornecer compostos naturais úteis, como já foi mostrado para outras espécies de Virola. Por isso, o objetivo deste estudo foi determinar a composição química dos extratos do tronco e das folhas de V. venosa e os possíveis potenciais antioxidantes e de inibição contra α-glucosidase de seus compostos. Os extratos polares mostraram-se mais ativos em ambos os testes, portanto, um fracionamento guiado por bioatividade foi realizado para designar os compostos responsáveis pelas atividades registradas. Através da combinação de análise CL-EM/EM e isolamento com identificação por RMN, foram identificados oito compostos fenólicos. Testes com os compostos puros principais das frações mais ativas indicaram o ácido ferúlico como o principal contribuinte das atividades biológicas observadas para os extratos brutos, e, consequentemente, o princípio ativo principal de V. venosa.
  • Hydrological calibration and validation of the MGB-IPH model for water
           resource management in the upper Teles Pires River basin in the
           Amazon-Cerrado ecotone in Brazil

    • Abstract: ABSTRACT The upper Teles Pires River basin is located in the Brazilian agriculture frontier in the north of Mato Grosso state and has experienced significant changes in land use and cover, which can cause major changes in its hydrological dynamics. Climatic and hydrologic data are scarce in the region, which poses uncertainties in the decision-making process aiming at the sustainable management of water resources in this strategic area. The aim of this study was to evaluate the performance of the Large-Scale Distributed Hydrological Model (MGB-IPH) to assess water availability of the upper Teles Pires basin and support water resource management in the Amazon-Cerrado ecotone. The MGB-IPH model was calibrated and validated using data from three streamflow stations available in the basin. In order to verify the model performance, the Nash-Sutcliffe (NS) and the PBIAS statistical parameters were applied. Our results show that, by using the MGB-IPH model with generally available data, the maximum and minimum flow regimes can be successfully assessed in the upper Teles Pires basin. The continuity curves of daily flow simulated by the model showed a good fit with the observed flow. Overall, the results demonstrated the applicability of the MGB-IPH model for water resource assessment and management in the basin.RESUMO A bacia do alto Rio Teles Pires está localizada na região de fronteira agrícola no norte de Mato Grosso, onde significativas mudanças no uso e cobertura do solo vem ocorrendo, o que, por sua vez, pode resultar em alterações importantes na dinâmica hidrológica da bacia. Dados climáticos e hidrológicos são escassos na bacia, o que gera dificuldades para a gestão sustentável dos recursos hídricos nesta região estratégica. No presente trabalho, avaliamos o desempenho do Modelo de Grandes Bacias (MGB-IPH) para a estimativa da disponibilidade hídrica da bacia do alto Teles Pires, visando o suporte à tomada de decisões para a gestão hídrica no ecótono Amazônia-Cerrado. O modelo MGB-IPH foi calibrado e validado utilizando séries históricas de três estações hidrométricas presentes na bacia. Para avaliação da qualidade do modelo, foram empregados os índices estatísticos de desempenho de Nash-Sutcliffe (NS) e a porcentagem BIAS (PBIAS). Com base nos resultados é possível afirmar que a utilização do modelo MGB-IPH possibilita a estimativa das vazões mínimas e máximas da bacia do alto Teles Pires de forma satisfatória. As curvas de continuidade das vazões diárias simuladas pelo modelo apresentaram um bom ajuste com os dados observados. Os resultados demonstram a aplicabilidade do modelo MGB-IPH como ferramenta de apoio à avaliação e gestão dos recursos hídricos na bacia.
  • Diversity of yeasts during fermentation of cocoa from two sites in the
           Brazilian Amazon

    • Abstract: ABSTRACT The purpose of this study was to identify the yeasts involved in spontaneous fermentation of cocoa from the Brazilian Amazon region. The fermentation process was carried out experimentally with cocoa seeds from two sites (Medicilândia and Tucumã), State of Pará, northern Brazil, during a six-day period. Totals of 44 yeasts were isolated from Medicilândia and 29 from Tucumã. Molecular identification was carried out by sequencing the D1/D2 region fragment of the rRNA 26S gene, expanded with universal primers for the NL1GC and LS2 eukaryotes. Pichia manshurica and Saccharomyces cerevisiae were identified in Medicilândia and five yeast species (Pichia fermentans, P. kudriavzevii, P. manshurica, S. cerevisiae and Zygosaccharomyces bailii) were identified in Tucumã. The results showed that P. manshurica and S. cerevisiae may have potential for use as starter cultures in future studies to improve the quality of cocoa seeds fermented in the Brazilian Amazon region.RESUMO A proposta deste estudo foi identificar as leveduras envolvidas na fermentação espontânea de cacau da Amazônia brasileira. A fermentação foi realizada em Medicilândia e Tucumã, Pará, Brasil, durante 6 dias. Em total foram obtidos 44 isolados de leveduras de Medicilândia e 29 de Tucumã. A identificação molecular foi realizada por sequenciamento do fragmento da região D1/D2 do gene rRNA 26S, amplificado com primers universais para eucariotos NL1GC e LS2. Em Medicilândia, foram identificadas Pichia manshurica e Saccharomyces cerevisiae. Em Tucumã foram identificadas cinco espécies (Pichia fermentans, P. kudriavzevii, P. manshurica, S. cerevisiae e Zygosaccharomyces bailii). Os resultados sugerem que P. manshurica e S. cerevisiae podem ter potencial para uso como culturas starter em estudos futuros, para melhorar a qualidade das sementes de cacau fermentadas na Amazônia brasileira.
  • First record of Aedes (Stegomyia) albopictus in the state of Amapá,
           northern Brazil

    • Abstract: ABSTRACT We report the first record of Aedes albopictus (Diptera: Culicidae) in the state of Amapá, northern Brazil. Two female specimens were collected from a Shannon trap in the locality of Ilha de Santana, municipality of Santana, Amapá. The occurrence of the species was confirmed with the installation of ten ovitraps. Aedes albopictus is a species of epidemiological importance for the transmission of arboviruses. Amapá was one of two Brazilian states without any record of this species.RESUMO Relatamos o primeiro registro de Aedes albopictus (Diptera: Culicidae) no Estado do Amapá, no norte do Brasil. Dois espécimes foram coletados em uma armadilha de Shannon na localidade de “Ilha de Santana”, município de Santana, no Amapá. O registro foi confirmado com a instalação de dez ovitrampas. Aedes albopictus é uma espécie com importância epidemiológica na transmissão de arboviroses. O Amapá era um de dois estados brasileiros sem registro dessa espécie.
  • Alternative vibro-dynamic compression processing of wood-cement composites
           using Amazonian wood

    • Abstract: ABSTRACT Wood-cement composite (WCC) is a potential construction material for tropical regions, due to its physico-mechanical properties and resistance to decay and fungi attack. However it is important to test alternative production methods and wood materials that are easier and cheaper than those traditionally used, in order to create a higher demand for this product. The aim of this work was to evaluate the use of wood from four Amazonian species (Eschweilera coriaceae, Swartzia recurva, Manilkara amazonica and Pouteria guianensis) in the production of wood-cement composites through a vibro-dynamic compression process, an alternative method to the use of a hydraulic press. The inhibition degree caused by the wood to the cement cure, measured by the factor CA, indicated that all species were compatible with Portland cement (CP II-Z). WCC with densities higher than 1,100 kg m-3 (produced with E. coriaceae and S. recurva particles) showed compressive strength values higher than 10 MPa, which fulfills the minimum requirement for lightweitgh reinforced concrete blocks for structural use.RESUMO Compósito madeira-cimento é um potencial material de construção para regiões tropicais, devido a suas propriedades físico-mecânicas e resistência ao ataque de fungos e podridão. Contudo, é importante testar métodos alternativos de produção e madeiras que sejam mais simples e baratos do que os tradicionalmente usados, para que se alcance uma maior demanda para esse produto. O objetivo deste estudo foi avaliar o uso de madeira de quatro espécies amazônicas (Eschweilera coriaceae, Swartzia recurva, Manilkara amazonica e Pouteria guianensis) na produção de compósitos de madeira-cimento (WCC) pelo processo de compactação vibro-dinâmica, um método alternativo que dispensa o uso de prensas hidráulicas. O grau de inibição à pega do cimento causado pela presença da madeira foi medido pelo fator CA e indicou que todas as quatro espécies foram compatíveis com o cimento Portland (CP II-Z). Compósitos com massa específica superior a 1.100 kg m-3 (produzidas com partículas de E. coriaceae e S. recurva) apresentaram valores de compressão axial acima de 10 MPa, requisito mínimo para classificar como blocos de concreto reforçados leves de uso estrutural.
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
Home (Search)
Subjects A-Z
Publishers A-Z
Your IP address:
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-