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1.
An Acad Bras Cienc ; 96(suppl 2): e20230529, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422354

RESUMO

This research was conducted for the purpose to evaluate the contribution Giant petrels and Brown skuas nestings in the formation of ornithogenic soils by the phosphatization process in Harmony Point, Maritime Antarctic. Ten nests were selected to collect topsoil samples (0-20 cm), from 0 m up to 20 m away, with regular spacing of 2 m. The analysis of the samples included the physical, chemical, mineralogical and geochemical analyzes. Phosphate minerals were identified. The presence of high content of some trace elements, such as Zn, Cu and Sr is associated with the bird's excrements. Total-P and bioavailable-P recorded higher levels. This result demonstrates the importance of the time factor in the bird's nesting, as well as in the development of the soil in these soil-forming environment. Phosphatization in these areas is not restricted to the specific location of the nest, since high values of P have been identified at distances between 8 and 12 m, from de nest's top. This suggests the transport of P rich solutions and phosphatized material along fractures by the freeze-thaw cycles, contributing to increase the geographical expression of this phenomenon in this ice-free area, consequently the development of soils and the establishment of vegetation.


Assuntos
Solo , Oligoelementos , Animais , Solo/química , Regiões Antárticas , Aves , Oligoelementos/análise , Minerais
2.
An Acad Bras Cienc ; 95(suppl 3): e20210692, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37585979

RESUMO

Active layer and permafrost are important indicators of climate changes in periglacial areas of Antarctica, and the soil thermal regime of Maritime Antarctica is sensitive to the current warming trend. This research aimed to characterize the active layer thermal regime of a patterned ground located at an upper marine terrace in Half Moon Island, during 2015-2018. Temperature and moisture sensors were installed at different soil depths, combined with air temperature, collecting hourly data. Statistical analysis was applied to describe the soil thermal regime and estimate active layer thickness. The thermal regime of the studied soil was typical of periglacial environment, with high variability in temperature and water content in the summer, resulting in frequent freeze-thaw cycles. We detected dominant freezing conditions, whereas soil temperatures increased, and the period of high soil moisture content lasted longer over the years. Active layer thickness varied between the years, reaching a maximum depth in 2018. Permafrost degradation affects soil drainage and triggers erosion in the upper marine terrace, where permafrost occurrence is unlikely. Longer monitoring periods are necessary for a detailed understanding on how current climatic and geomorphic conditions affect the unstable permafrost of low-lying areas of Antarctica (marine terraces).


Assuntos
Pergelissolo , Regiões Antárticas , Solo , Água , Temperatura
3.
An Acad Bras Cienc ; 94(suppl 1): e20201141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35384970

RESUMO

This study characterized the physical, chemical, macro- and micromorphological soil properties from three successive marine terrace levels from Harmony Point (Nelson Island, Maritime Antarctica) in order to understand the pedological signatures of Quaternary coastal landscape evolution of Maritime Antarctica. Soils were sampled on the Late Holocene beach (current beach) and Mid Holocene marine terraces higher up, at 3, 8, and 12 m a.s.l. At the lower levels, the predominant soils were Gelorthents, whereas Haplogelepts dominate the higher terraces. Soil properties are mostly influenced by parent material and faunal activity, in which cryoclastic (thermal weathering) and phosphatization are the main soil-forming processes. Soils from the upper levels are more developed, deeper with reddish colors, granular structures and incipient formation B horizon. These horizonation features highlight that soils vary according with age of glacier-isostatic terrace uplift, representing a Quaternary soil chronosequence. All marine terrace levels are Ornithogenic soils, at varying degrees. However, the presence of old bird nesting sites for long periods led to formation of phosphatic horizons, stable Fe-phosphate minerals and abundant vegetation in the highest terraces of this part of Maritime Antarctica.


Assuntos
Microbiologia do Solo , Solo , Regiões Antárticas , Minerais , Solo/química
4.
Mem Inst Oswaldo Cruz ; 107(4): 466-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22666855

RESUMO

Cryptococcus neoformans is the most common causative agent of cryptococcosis worldwide. Although this fungus has been isolated from a variety of organic substrates, several studies suggest that hollow trees constitute an important natural niche for C. neoformans. A previously surveyed hollow of a living pink shower tree (Cassia grandis) positive for C. neoformans in the city of Rio de Janeiro, Brazil, was chosen for further investigation. Odontomachus bauri ants (trap-jaw ants) found inside the hollow were collected for evaluation as possible carriers of Cryptococcus spp. Two out of 10 ants were found to carry phenoloxidase-positive colonies identified as C. neoformans molecular types VNI and VNII. The ants may have acted as a mechanical vector of C. neoformans and possibly contributed to the dispersal of the fungi from one substrate to another. To the best of our knowledge, this is the first report on the association of C. neoformans with ants of the genus Odontomachus.


Assuntos
Formigas/microbiologia , Cassia/microbiologia , Cryptococcus neoformans/isolamento & purificação , Animais , Formigas/classificação , Brasil , Cassia/classificação , Cryptococcus neoformans/genética , Técnicas de Tipagem Micológica
5.
J Med Entomol ; 56(3): 849-858, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30649408

RESUMO

The present study evaluated the diversity of Anopheles Meigen, 1818 belonging to the subgenus Nyssorhynchus Blanchard, 1902 in four areas of Cachoeiras de Macacu municipality, Rio de Janeiro, Brazil. The immature collections were carried out during a rainy period and a post-rainy season. During the two periods, 3,932 specimens of Anopheles (Nyssorhynchus) were collected: 562 in the rainy period (14.29%) and 3,370 in the post-rainy period (85.70%). Among 3,932 specimens collected during both periods, 489 were identified, 50 (8.89%) in the rainy period and 439 (13.02%) in the post-rainy period. Nine Anopheles species were recorded: Anopheles albitarsis Lynch Arribálzaga, 1878 s.l. (76.86%), An. braziliensis (Chagas, 1907) (17%); An. evansae (Bréthes, 1926) (8, 48%); An. triannulatus (Neiva & Pinto, 1922) s.l. (8.23%); An. oswaldoi (Peryassú, 1922) (6.43%); An. strodei Root, 1926 (5.40%); An. argyritarsis Robineau-Desvoidy, 1827 (1.54%); An. rangeli Gabaldón et al., 1940 (1.28%); and An. aquasalis Curry, 1932 (0.51%). Among them, An. albitarsis was dominant and abundant in 93.75% of the collection points. Our results show a diverse Anopheles fauna in the municipality of Cachoeiras de Macacu, with a strong association of occurrence between An. rangeli and An. oswaldoi; An. rangeli and An. evansae; An. evansae and An. oswaldoi; and An. albitarsis s.l. and An. braziliensis during the rainy period. However, there was a weak correlation in the post-rainy period, except between An. rangeli and An. oswaldoi and between An. triannulatus and An. aquasalis, which displayed a moderate linear correlation. Our results suggest that following a potential reintroduction of malaria Cachoeiras de Macacu, local transmission of Plasmodium Marchiafava & Celli, 1885 may be enhanced by the presence of nine Nyssorhynchus species (all potential malaria vectors).


Assuntos
Distribuição Animal , Anopheles/fisiologia , Biodiversidade , Mosquitos Vetores/fisiologia , Animais , Brasil , Densidade Demográfica , Estações do Ano
6.
Rev Inst Med Trop Sao Paulo ; 59: e60, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28793027

RESUMO

Haemagogus leucocelaenus, which is considered a major vector of wild yellow fever, exhibits acrodendrophilic habits and mainly deposits its eggs in treeholes and bamboo internodes. The selection of nursery sites is essential in the life history and reproductive success of mosquitoes. The present work investigated the preferred oviposition height and period of Hg. leucocelaenus in an Atlantic forest area in Rio de Janeiro. Sampling was performed using oviposition traps that were placed on plant material at 0, 2, 4, 6, and 8 m above the ground, from August 2015 to July 2016. Eggs were more abundant during October and May, and the height of traps placement had no significant effect on the eggs number indicating that Hg. leucocelaenus explores different levels of forest habitats, a behavior that may favor the transmission of pathogens among arboreal animals including primates and humans. The findings of the present study are discussed from an ecological and epidemiological point of view.


Assuntos
Culicidae/fisiologia , Insetos Vetores/fisiologia , Oviposição/fisiologia , Animais , Brasil , Culicidae/anatomia & histologia , Feminino , Insetos Vetores/anatomia & histologia , Densidade Demográfica , Estações do Ano , Febre Amarela/transmissão
8.
Rev Panam Salud Publica ; 26(6): 553-9, 2009 Dec.
Artigo em Português | MEDLINE | ID: mdl-20107711

RESUMO

The present article aims at contextualizing the first Brazilian experience with compulsory licensing, which functions as a defense mechanism to prevent excessive pricing by holders of patents. According to this mechanism, a government can authorize a third party to explore the patented object (in this case a drug) without previous consent from the patent holder. On May 4, 2007, Brazil officially issued compulsory licensing of the antiretroviral drug efavirenz for public, non-commercial use. Initially, generic versions of the drug were purchased from laboratories in India. The next step was the manufacture of efavirenz by Farmanguinhos, official pharmaceutical laboratory (Fundação Osvaldo Cruz). It is concluded that the decision made by the Brazilian government to issue compulsory licensing of efavirenz was correct, taking into account the projected savings of US$ 236.8 until 2012 and the guarantee of availability of efavirenz, the most usual free antiretroviral treatment provided in Brazil.


Assuntos
Fármacos Anti-HIV , Benzoxazinas , Patentes como Assunto , Alcinos , Brasil , Ciclopropanos
10.
Mem. Inst. Oswaldo Cruz ; 107(4): 466-469, June 2012. ilus
Artigo em Inglês | LILACS | ID: lil-626438

RESUMO

Cryptococcus neoformans is the most common causative agent of cryptococcosis worldwide. Although this fungus has been isolated from a variety of organic substrates, several studies suggest that hollow trees constitute an important natural niche for C. neoformans. A previously surveyed hollow of a living pink shower tree (Cassia grandis) positive for C. neoformans in the city of Rio de Janeiro, Brazil, was chosen for further investigation. Odontomachus bauri ants (trap-jaw ants) found inside the hollow were collected for evaluation as possible carriers of Cryptococcus spp. Two out of 10 ants were found to carry phenoloxidase-positive colonies identified as C. neoformans molecular types VNI and VNII. The ants may have acted as a mechanical vector of C. neoformans and possibly contributed to the dispersal of the fungi from one substrate to another. To the best of our knowledge, this is the first report on the association of C. neoformans with ants of the genus Odontomachus.


Assuntos
Animais , Formigas/microbiologia , Cassia/microbiologia , Cryptococcus neoformans/isolamento & purificação , Formigas/classificação , Brasil , Cassia/classificação , Cryptococcus neoformans/genética , Técnicas de Tipagem Micológica
12.
Rev. panam. salud pública ; 26(6): 553-559, dic. 2009.
Artigo em Português | LILACS | ID: lil-536497

RESUMO

The present article aims at contextualizing the first Brazilian experience with compulsory licensing, which functions as a defense mechanism to prevent excessive pricing by holders of patents. According to this mechanism, a government can authorize a third party to explore the patented object (in this case a drug) without previous consent from the patent holder. On May 4, 2007, Brazil officially issued compulsory licensing of the antiretroviral drug efavirenz for public, non-commercial use. Initially, generic versions of the drug were purchased from laboratories in India. The next step was the manufacture of efavirenz by Farmanguinhos, official pharmaceutical laboratory (Fundação Osvaldo Cruz). It is concluded that the decision made by the Brazilian government to issue compulsory licensing of efavirenz nwas correct, taking into account the projected savings of US$ 236.8 until 2012 and the guarantee of availability of efavirenz, the most usual free antiretroviral treatment provided in Brazil.


Assuntos
Fármacos Anti-HIV , Benzoxazinas , Patentes como Assunto , Brasil
13.
J Biol Inorg Chem ; 7(6): 640-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12072970

RESUMO

The uptake of carcinogenic and mutagenic Cr compounds and the intracellular distribution of their biotransformation products in V79 Chinese hamster lung cells were studied by synchrotron-radiation-induced X-ray emission (SRIXE). SRIXE analysis was performed on whole cells that had been treated with either Cr(III) or Cr(V) 1,10-phenanthroline complexes, or Cr(VI). The high spatial resolution (0.3 microm) and elemental sensitivity (~10(-15) g Cr/cell) of the technique provided detailed maps of Cr and other cellular elements in thin sections prepared from Cr(VI)-treated cells. The Cr carcinogen concentrated in P-rich regions corresponding to the nucleus, as well as other areas of the cell that are likely to correspond to organelles. This is the first study that has enabled the determination of the localization of the biotransformation products of Cr(VI) carcinogens in a target lung cell.


Assuntos
Compostos de Cromo/farmacocinética , Cromo/farmacocinética , Pulmão/metabolismo , Animais , Biotransformação , Testes de Carcinogenicidade , Linhagem Celular , Cromo/toxicidade , Compostos de Cromo/toxicidade , Cricetinae , Cricetulus , Microanálise por Sonda Eletrônica/instrumentação , Microanálise por Sonda Eletrônica/métodos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Sensibilidade e Especificidade , Difração de Raios X
14.
Ciênc. rural ; 38(2): 518-521, mar.-abr. 2008. tab
Artigo em Português | LILACS | ID: lil-474522

RESUMO

O objetivo deste estudo foi determinar as espécies de Tephritidae e Lonchaeidae (Diptera: Tephritoidea) de ocorrência em pomares de laranja doce (Citrus sinensis Osbeck) e tangerina (Citrus reticulata Blanco), no município de Araruama, RJ, durante o período de dezembro de 2002 a novembro de 2003. Os espécimes foram coletados em armadilhas McPhail contendo solução aquosa de proteína hidrolisada a 5 por cento e em amostras de frutos de seis variedades de citros. Nas armadilhas, o total de 2.543 adultos de Tephritoidea (1.430 fêmeas e 1.023 machos) foi capturado, sendo dez espécies de Tephritidae, quatro espécies e dois morfotipos de Lonchaeidae. Dos Tephritidae e capturados nas McPhail, quatro espécies (Anastrepha fraterculus, A. obliqua, A. sororcula e Ceratitis capitata) infestaram frutos cítricos, enquanto que, dos Lonchaeidae, somente os morfotipos não infestaram as amostras de citros. Os resultados demonstram que a densidade populacional das moscas-das-frutas pode ser superestimada, quando baseada no número de moscas por armadilha, devido à captura de espécies que não infestam os frutos de interesse comercial.


This study was aimed at determining the species of Tephritidae and Lonchaeidae (Diptera: Tephritoidea) that occur on groves of sweet orange (Citrus sinensis Osbeck ) and tangerine (Citrus reticulata Blanco) in the municipality of Araruama, state of Rio de Janeiro, Brazil, from December, 2002 to November, 2003. The specimens were collected by McPhail traps with aqueous solution of hydrolyzed protein to 5 percent and in fruits samples of six varieties of citrus. In the traps the total of 2,543 adults of Tephritoidea (1,430 females and 1,023 males) was captured, being ten species of Tephritidae, four species and two morphotypes of Lonchaeidae. From the Tephritidae caught by the McPhail, four species (Anastrepha fraterculus, A. obliqua, A. sororcula and Ceratitis capitata) infested citric fruits while the Lonchaeidae, the morphotypes did not infest the citrus. The results showed that the population density of fruit flies may be overestimated when based on the number of flies per trap due to the capture of species that not infest the fruits of commercial interest.

16.
Neotrop. entomol ; 34(6): 1017-1021, Nov.-Dec. 2005. tab
Artigo em Português | LILACS | ID: lil-451306

RESUMO

A citricultura fluminense vem sofrendo com os problemas fitossanitários, levando a baixa produção. Esse problema está ligado ao baixo conhecimento das espécies de insetos associado ao citros. O objetivo do trabalho foi estudar a distribuição geográfica das espécies de insetos fitófagos associados aos citros em 17 municípios do estado do Rio de Janeiro, de janeiro de 2000 a junho de 2001 em quatro regiões: Baixada Fluminense, Região Serrana, Região das Baixadas Litorâneas (região citrícola) e Região Noroeste do estado. As amostragens foram realizadas em um pomar por município, através da metodologia presença-ausência. Em três municípios foi verificada a ocorrência das 11 espécies e em outros três municípios observou-se menor número de espécies, apenas seis. As espécies com maior distribuição geográfica foram: Aleurothrixus floccosus (Maskell) e Selenaspidus articulatus (Morgan), ocorrendo em 16 municípios. As duas espécies com menor distribuição foram Lepidosaphis beckii (Newman) e Toxoptera citricida (Kirkaldy), presentes em sete e 10 municípios respectivamente.


The phytosanitary problems leading to lower citrus production in the state of Rio de Janeiro are due to the insufficient knowledge on insect species affecting citrus orchards. The objective of this research was to study the geographic distribution of phytophagous insect species, associated with citrus production, in 17 municipalities of Rio de Janeiro, from January 2000 to June 2001. The municipalities are located in four regions: Baixada Fluminense (the lowland region), Região Serrana (the mountain region), Região das Baixadas Litorâneas (the citrus producing marshland region) and Região Noroeste (the Northern region). Samples were collected from one orchard in each municipality by means of the presence or absence methodology. Eleven species were found in three municipalities and six species were found in three others. The species Aleurothrixus floccosus (Maskell) and Selenaspidus articulatus (Morgan) were found in 16 municipalities. Lepidosaphis beckii (Newman) and Toxoptera citricida (Kirkaldy) were found in only seven and 10 municipalities, respectively.


Assuntos
Demografia , Ecologia , Controle de Insetos , Insetos , Plantas , Características de Residência
17.
Acta amaz ; 11(1)1981.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1453710

RESUMO

Summary Guatteriopsis friesiana W. Rodrigues is described as a new species of Annonaceae, which is readily separated from the other 4 species of the same genus especially by its leaves discolour and cordate at the base and in particular from G. kuhlmannii Fries by the outline of its flower buds. A synoptical key for identification of the species of Guatteriopsis is included.


Resumo Guatteriopsis friesiana W. Rodrigues (Annonaceae), arvoreta relativamente freqüente nas matas de terra firme das cercanias de Manaus. Amazonas, Brasil, é descrita neste trabalho como espécie nova. Inclui este artigo uma chave sinótica para identificação das espécies de Guatteriopsis até então conhecidas

18.
Acta amaz ; 11(4)1981.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1453817

RESUMO

Summary Iryanthera inpae W. Rodrigues is presented as a new species of Myristicaceae from brazilian Amazonia, which is very similar to I. tricornis Ducke in leaf morphology, but differs mainly in the size of the flowers and habit of the fruits. The specific epithet is in honor of the herbarium number 100.000 of the National Research Institute of Amazonia (INPA).

19.
Acta amaz ; 12(2)1982.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1453862

RESUMO

Resumo Iryanthera campinae W. Rodr. (Myristicaceae) e Vantanea deniseae W. Rodr. (Humiriaceae) são descritas como novas espécies da flora amazônica.

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