73 resultados para ENTERPRISE FOR THE AMERICAS INITIATIVE
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Astrobiology is a transdisciplinary field with extraordinary potential for the scientific community. As such, it is important to educate the community at large about the growing importance of this field to increase awareness and scientific content learning and expose potential future scientists. To this end, we propose the creation of a traveling museum exhibit that focuses exclusively on astrobiology and utilizes modern museum exhibit technology and design. This exhibit (the Astrobiology Road Show), organized and evaluated by an international group of astrobiology students and postdocs, is planned to tour throughout the Americas. Copyright © 2013, Mary Ann Liebert, Inc. 2013.
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Insect pest phylogeography might be shaped both by biogeographic events and by human influence. Here, we conducted an approximate Bayesian computation (ABC) analysis to investigate the phylogeography of the New World screwworm fly, Cochliomyia hominivorax, with the aim of understanding its population history and its order and time of divergence. Our ABC analysis supports that populations spread from North to South in the Americas, in at least two different moments. The first split occurred between the North/Central American and South American populations in the end of the Last Glacial Maximum (15,300-19,000 YBP). The second split occurred between the North and South Amazonian populations in the transition between the Pleistocene and the Holocene eras (9,100-11,000 YBP). The species also experienced population expansion. Phylogenetic analysis likewise suggests this north to south colonization and Maxent models suggest an increase in the number of suitable areas in South America from the past to present. We found that the phylogeographic patterns observed in C. hominivorax cannot be explained only by climatic oscillations and can be connected to host population histories. Interestingly we found these patterns are very coincident with general patterns of ancient human movements in the Americas, suggesting that humans might have played a crucial role in shaping the distribution and population structure of this insect pest. This work presents the first hypothesis test regarding the processes that shaped the current phylogeographic structure of C. hominivorax and represents an alternate perspective on investigating the problem of insect pests. © 2013 Fresia et al.
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A phylogenetic analysis based on nuclear ITS and plastid trnK intron sequences confirms that Dahlgrenodendron, Sinopora, Triadodaphne, and Yasunia are members of the Cryptocarya group, as expected from morphology. Dahlgrenodendron from South Africa is sister to Aspidostemon from Madagascar. Triadodaphne inaequitepala is nested within Endiandra (both from Australasia), and Yasunia from South America is nested among South American Beilschmiedia species. Sinopora is a member of the Beilschmiedia clade, but its precise position is still uncertain. Among large genera of the group, Cryptocarya is clearly monophyletic, and Endiandra appears to be as well, if T. inaequitepala is included. Beilschmiedia is paraphyletic with respect to (at least) Potameia and Yasunia. Most well-supported clades within genera are geographically homogeneous, except a clade including the Chilean Cryptocarya alba and two New Caledonian species. Both Beilschmiedia and Cryptocarya have reached the Americas more than once. Four-locular anthers are plesiomorphic in the Cryptocarya group; two-locular anthers have arisen by fusion of the two pollen sacs of a theca. In the plesiomorphic fruit type, the ovary is completely enclosed in receptacular tissue; a superior fruit, seated free on its pedicel, is a synapomorphy of the Beilschmiedia clade.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A lagarta do cartucho do milho é uma das principais pragas do milho nas Américas, podendo ocorrer durante todos os estágios de crescimento da cultura, causando perdas de 15 a 37% na produção. Neste trabalho estudou-se a distribuição espacial dessa praga no campo, com a finalidade de desenvolver um sistema de amostragem para estimar sua densidade populacional. Na área cultivada com milho foram selecionados 3 campos experimentais de 40 m x 250 m cada, divididos em 100 parcelas cada. Foram contados o número de lagartas pequenas e grandes de S. frugiperda nas folhas e no cartucho das plantas, em 10 plantas ao acaso por parcela, num total de 1000 plantas por campo, em 5, 5 e 4 datas de amostragem, respectivamente. Lagartas menores que 1 cm eram consideradas pequenas e lagartas maiores que 1 cm, grandes. Foram estimados os parâmetros da lei de Taylor, sendo as estimativas dos parâmetros das regressões altamente significativas para todas as categorias larvais. O parâmetro b da lei de Taylor para lagarta pequena foi igual a 1,57, indicando que a forma de distribuição dessa categoria larval é agregada. Para lagartas grandes o parâmetro b foi igual a 0,79, o que conduz a um tipo de distribuição tendendo para aleatoriedade. Para o número total de lagartas os resultados são equivalentes aos obtidos para lagartas pequenas. Foi desenvolvido um plano de amostragem seqüencial com base nos parâmetros da lei de Taylor.
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Os dentes de cutias (Dasyprocta azarae) foram descritos macroscopicamente para fornecer informações sobre um dos maiores roedores das Américas. Radiografias foram realizadas em seis cabeças, e os dentes foram descritos. O esmalte envolve a dentina coronal e se projeta até a raiz e é presente como lâminas dispostas paralelamente em direção vestíbulolingual. A dentina é localizada entre as lâminas do esmalte e envolve os cornos pulpares. O cemento é localizado internamente às lâminas de esmalte. Na superfície lingual, o cemento e a dentina são os elementos mais externos.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The fall armyworm, Spodoptera frugiperda (J. E. Smith), is one of the most important maize pests in the Americas and particularly in South America. With the adoption of genetically modified plants expressing Bacillus thuringiensis toxins for lepidopterous pest control, there is a need for establishing strategies to delay the development of insect resistance (e.g. refuge areas). Thus, information on target insects' dispersal is essential to improve pest management techniques. The objective of this work was to evaluate the dispersal capacity of S. frugiperda adults using mark-release-recapture techniques. Insects were marked using red oil-soluble dye in the larval artificial diet. Marked adults were released twice in each growing season (dry and wet) in southeastern Brazil in 2006 and 2007. Recapture of marked insects was performed using light and pheromone traps. Males are more attracted to light traps than females and the recapture rate was higher in the dry season than in the rainy season. The most adequate model to explain the relationship between flight distance and number of recaptured insects is y = a(2)/ (1+ (2a(1.8)+ bx))((2.6)), where y is the distance and x is the number captured. The maximum recapture distances were 806 m for males and 608 m for females. Therefore, strategies for establishment of refuges should take such distances into consideration.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The stink bugs genus Atopozelus (Hemiptera: Reduviidae) is native in the Americas, with five described species of which only three have been recorded in Brazil. In August 2007, Eucalyptus camaldulensis leaves infested by lerp psyllid were collected and taken to the Forest Pest Biological Control Laboratory situated at São Paulo State University. A small green stink bug, identified as Atopozelus opsimus Elkins (Hemiptera: Reduviidae) that fed on nymphs and adult psyllids, was found on the leaves. These stink bugs presented phytophagy, omnivory and ability in opening the lerp (shell) that protect the psyllid. A. opsimus has demonstrated unusual particularities, different from many biological control agents found in nature; this predator thus deserves more attention for its potential to be evaluated.
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Coatis [including Nasua nasua, the ring-tailed coati], are medium-sized mammals widely distributed in the Americas. They are social animals, whose normal diet includes insects, fruits, and small vertebrates, and rarely prey on larger sized animals. There are, to our knowledge, no reports in the medical literature of attacks on humans. This report describes a coati attack on 2 children in their home. The children sustained deep scratches and bites. The animal may have injured the humans in a defensive strike, but motivation for attack was uncertain. Coati attacks may occur in places where there is interaction between these mammals and humans.
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Leishmaniasis is a parasitic zoonosis caused by protozoans of the genus Leishmania transmitted by insects known as phlebotomines, which are found in wild or urban environments. It affects domestic and wild animals and transmission to man happens by accident. The disease occurs in tropical and sub-tropical areas, mainly in Asia, Europe, Africa, and the Americas. There are two forms that affect man: American cutaneous leishmaniasis (ACL) and American visceral leishmaniasis (AVL). The latter is caused by three species of Leishmania: Leishmania (Leishmania) donovani, Leishmania (Leishmania) infantum, and Leishmania (Leishmania) chagasi, which are grouped in the Leishmania (Leishmania) donovani complex. Wild reservoir hosts of L. chagasi known so far are foxes and marsupials. In domestic environment, dogs are the most important reservoir hosts and sources of infection to the vectors Lutzomyia longipalpis. Leishmaniasis is difficult to control, causing epidemic outbreaks, thus being an important public health problem. Due to lesions caused by the mucocutaneous type and the severity of those caused by the visceral type in humans, visceral leishmaniasis is one of the main public health concerns. This paper is part of the monograph presented at the end of the residency program in the field of Zoonosis and Public Health at the School of Veterinary Sciences and Animal Husbandry, São Paulo State University, UNESP, Botucatu, São Paulo State, Brazil, in 2005.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The mite Tetranychus mexicanus (McGregor) is considered a pest of a variety of plant species in the Americas. Although this mite apparently causes economic damage to Annonaceae, little is known about its biology Here we studied the biology of T. mexicanus on soursop (Annona muricata), sweetsop (Annona squamosa) and araticum (Annona coriaceae). The first two species are the most important economical Annonaceae species in northeast Brazil; araticum is commonly found in the region, but not commercially explored. The mites were collected in the field from leaves of A. muricata and maintained in the laboratory for six months on detached leaves of A. muricata, A.squamosa and A. coriaceae, respectively, before observations started. Tetranychus mexicanus developed more slowly on A. squamosa than on the two other hosts, but oviposition was considerably lower on A. coriaceae. As indicated by the calculated life table parameters, biotic potential was higher on A. muricata than on the other hosts. Despite the observed differences in the T. mexicanus biology on the different evaluated hosts, development and reproduction were satisfactory in all of the hosts used.