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931.
932.
Octavio Miramontes Og DeSouza Diego Hernández Eliane Ceccon 《Human ecology: an interdisciplinary journal》2012,40(2):167-174
We measured mobility patterns that describe walking trajectories of individual Me’Phaa peasants searching for and collecting
fuel wood in the forests of “La Monta?a de Guerrero” in Mexico. These 1-day excursions typically follow a mixed pattern of
nearly-constant steps when individuals displace from their homes towards potential collecting sites and a mixed pattern of
steps of different lengths when actually searching for fallen wood in the forest. Displacements in the searching phase seem
not to be compatible with Lévy flights described by power-laws with optimal scaling exponents. These findings, however, can
be interpreted in the light of deterministic searching on heavily degraded landscapes where the interaction of the individuals
with their fuel wood-scarce environment produces alternative searching strategies than the expected Lévy flights. These results
have important implications for future management and restoration of degraded forests and the improvement of the ecological
services they may provide to their inhabitants. 相似文献
933.
934.
Daniela Camargos Costa Vanessa Pecini da Cunha Gabriela Maria Pereira de Assis Júlio César de Souza Junior Zelinda Maria Braga Hirano Mércia Eliane de Arruda Flora Satiko Kano Luzia Helena Carvalho Cristiana Ferreira Alves de Brito 《Memórias do Instituto Oswaldo Cruz》2014,109(5):641-643
Blood infection by the simian parasite, Plasmodium simium, was
identified in captive (n = 45, 4.4%) and in wild Alouatta clamitans
monkeys (n = 20, 35%) from the Atlantic Forest of southern Brazil. A single malaria
infection was symptomatic and the monkey presented clinical and haematological
alterations. A high frequency of Plasmodium vivax-specific
antibodies was detected among these monkeys, with 87% of the monkeys testing positive
against P. vivax antigens. These findings highlight the possibility
of malaria as a zoonosis in the remaining Atlantic Forest and its impact on the
epidemiology of the disease. 相似文献
935.
Valentin Jean L.; Monteiro-Ribas Wanda M.; Mureb M. Anita; Pessotti Eliane 《Journal of plankton research》1987,9(6):1195-1216
On some zooplankters common in the Cabo Frio (Brazil) upwelling.In the waters off Cabo Frio zooplankton maxima are observedbetween February and April, which is the period of upwellingoccurrence. Copepods are highly diversified; we identified 96species at a single collecting station during one year. In summerCalanoides carinatus, Paracalanus parvus and Oncea media areabundant, whereas we observed dominance of Temora stylifera,Clausocalanus furcatus, C. arcuicomis, Oithona plumifera andgreat quantity of Creseis acicula during winter. Chaetognatha(Sagitta enflata), Appendicularia (Oikopleura longicauda), Ostracoda(Conchoecia spp.) and Pteropoda (Limacina sp.) are permanentthroughout the year, and maximum in summer. The vertical distributionof zooplankton depends on the hydrological structure, i.e. natureof the water mass and degree of mixing between different waters.Brazil current water, with low quantity of organisms and dominanceof copepods (Clausocalanus furcatus, Mecynocera clausi, Corycaeidae,Oithonidae, Oncaeidae) accompanied by Evadne spinifera and Lucifertypicus. South Atlantic Central Water (upwelling water) characterizedby rare deep copepods and abundance of Calanoides carinatusand Ctenocalanus vanus which are excellent indicator speciesfor upwelling occurrence. Coastal water, with low salinity,where some species with brackish affinity are observed, likeOithona ovalis and Podon polyphemoides. 相似文献
936.
Chapmannia Torrey & Gray, a monotypic legume genus of Florida, is shown to have perfect flowers, rather than sterile and fertile flowers incorrectly attributed to the genus by authors for the past one hundred years. The species is described and illustrated with accompanying notes on its habitat, distribution, reproductive biology, phylogeny and cytology. 相似文献
937.
Pachecoa Standley & Steyerm., a monotypic legume genus of Mexico, Guatemala, and Venezuela, is described and illustrated with accompanying notes on its habitat, distribution, reproductive biology, phylogeny, cytology, and relationship (with key) to allied genera. 相似文献
938.
Anapaula Sommer Vinagre Ana Paula Nunes do Amaral Fabiana Pinto Ribarcki Eliane Fraga da Silveira Eduardo Prico 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,146(4):514
The aim of this study was to analyze the seasonal variations of carbohydrate and lipid metabolism of the ghost crab Ocypode quadrata (Fabricius, 1787) on a sandy beach in the southern region of Brazil. Crabs and hemolymph samples were collected monthly in the field. Hepatopancreas, gills, gonads and claw muscles were used for glycogen determination. In males, blood glucose levels increased in the summer and in the winter. The glycogen values increased significantly in the hepatopancreas in the winter, but remained constant in the muscle, gonads and gills. In females, hemolymph glucose levels, glycogen values in the hepatopancreas and in the gills remained constant throughout the year; however, muscular glycogen increased in the spring and gonad glycogen decreased in the summer. Hemolymph triglyceride levels of males and females and total cholesterol of males decreased significantly in the spring. In females, a significant increase of total cholesterol levels was found in the winter. The findings suggest that in O. quadrata lipids seem to be an important reserve of energy used during reproduction, both in males and females, while glycogen may be used during periods of intense activity or fasting. 相似文献
939.
Eliane Noirot 《Animal behaviour》1974,22(2):410-420
When a naïve virgin female mouse is exposed to an inaccessible litter so that it perceives the odour and the ultrasounds from the pups, its nest-building behaviour undergoes changes that are different from changes occurring in a control condition providing exposure to an inaccessible adult female. Virgin females exposed to a litter built their nest as near as possible to the pups. Other characteristics of their nest-building behaviour were influenced differently according to the type of ultrasound that the pups were emitting. In a condition where pups were mainly calling in response to cold, virgin females built heavier nests than control females. When mainly calls in response to handling were given by the pups, the females built lighter nests than control females. Finally, there was also some suggestion that the females exposed to ultrasounds from handled pups tended to chew the nest-material more than either control females or females exposed to ultrasound from cooled pups. 相似文献
940.
H. Taina Darius Catherine Dauga Patrick A. D. Grimont Eliane Chungue Paul M. V. Martin 《The Journal of eukaryotic microbiology》1998,45(6):619-627
ABSTRACT The diversity of symbiotic dinoflagellates (SD) from seven coral species ( Fungia scutaria, Fungia paumotensis, Lep-tastrea transversa, Pavona cactus, Pocillopora verrucosa, Montastrea curia , and Acropora fonnosa ) was studied in a restricted geographical area, the Lagoon of Arue on the island of Tahiti. Their diversity was explored by small subunit ribosomal RNA gene (SSU rDNA) restriction fragment length polymorphism (RFLP). After a nested amplification with SD specific primers, RFLP analyses were performed directly and after a cloning step. The diversity of these different SSU rDNA was estimated in respect to possible technical artifacts. In an axenic culture of SD from the coral Galaxea fascicularis , both heterogeneous SSU rDNAs and artifact molecules were observed as in our SD samples. According to the number of patterns observed, corals Fungia paumotensis, Leptastrea transversa. Pavona cactus, Montastrea curia, and Acropora fonnosa contained one class of SD SSU rDNAs. whereas Fungia scutaria and Pocillopora verrucosa contained three and two classes of SD SSU rDNAs respectively. In the limited geographic area studied. SD from different coral species shared the same pattern, except SD from Montastrea curta , which showed a unique pattern. In addition to the possibility of SD flux among different coral species, specific mechanisms could also be involved in the establishment of a symbiosis. 相似文献