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Bruno L. Mourato Fábio Hazin Keith Bigelow Michael Musyl Felipe Carvalho Humberto Hazin 《Fisheries Oceanography》2014,23(1):32-44
Spatial and temporal trends of sailfish catch rates in the southwestern and equatorial Atlantic Ocean in relation to environmental variables were investigated using generalized additive models and fishery‐dependent data. Two generalized additive models were fit: (i) ‘spatio‐temporal’, including only latitude, longitude, month, and year; and (ii) ‘oceanographic’, including sea surface temperature (SST), chlorophyll‐a concentration, wind velocity, bottom depth, and depth of mixed layer and year. The spatio‐temporal model explained more (average ~40%) of the variability in catch rates than the oceanographic model (average ~30%). Modeled catch rate predictions showed that sailfish tend to aggregate off the southeast coast of Brazil during the peak of the spawning season (November to February). Sailfish also seem to aggregate for feeding in two different areas, one located in the mid‐west Atlantic to the south of ~15°S and another area off the north coast of Brazil. The oceanographic model revealed that wind velocity and chlorophyll‐a concentration were the most important variables describing catch rate variability. The results presented herein may help to understand sailfish movements in the Atlantic Ocean and the relationship of these movements with environmental effects. 相似文献
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Morphohistological features of the tubular organs of the Myocastor coypus (coypu) female reproductive tract were studied. Specimens came from breeding farms with yard breeding systems. The analysis of the organs was made by histological methods and by macro and microscopic measurement techniques. The animals showed oviducts with macro and microscopically differentiable regions. Their mucosa showed primary branched folds in the ampullar sector. In the rest of the oviduct tract these folds were only of the primary type. The double uterus showed regional variations in the lumen, endometrial glands along the whole surface and a wide fibromuscular cervix with pseudoglands. The endocervical mucosa made clear a complex system of folds covered by a mucus-secreting epithelium. In the long vagina of the coypu a folded, rugose and irregular mucosa was observed. 相似文献
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The North American long-term soil productivity experiment: Findings from the first decade of research 总被引:1,自引:0,他引:1
Robert F. Powers D. Andrew Scott Felipe G. Sanchez Richard A. Voldseth Deborah Page-Dumroese John D. Elioff Douglas M. Stone 《Forest Ecology and Management》2005,220(1-3):31-50
First decade findings on the impacts of organic matter removal and soil compaction are reported for the 26 oldest installations in the nation-wide network of long-term soil productivity sites. Complete removal of surface organic matter led to declines in soil C concentration to 20 cm depth and to reduced nutrient availability. The effect is attributed mainly to the loss of the forest floor. Soil C storage seemed undiminished, but could be explained by bulk density changes following disturbance and to decomposition inputs of organic C from roots remaining from the harvested forest. Biomass removal during harvesting had no influence on forest growth through 10 years. Soil compaction effects depended upon initial bulk density. Soils with densities greater than 1.4 Mg m−3 resisted compaction. Density recovery was slow, particularly on soils with frigid temperature regimes. Forest productivity response to soil compaction depended both on soil texture and the degree of understory competition. Production declined on compacted clay soils, increased on sands, and generally was unaffected if an understory was absent. 相似文献
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Felipe Nogueira Soares Maria Emilia Franco Oliveira Luciana Cristina Padilha-Nakaghi Luís Guilherme de Oliveira Marcus Antônio Rossi Feliciano Felipe Brener Bezerra de Oliveira Pedro Paulo Maia Teixeira Wilter Ricardo Russiano Vicente Cristian Faturi Luiz Fernando de Souza Rodrigues 《Tropical animal health and production》2015,47(8):1465-1471
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Silvana Nisgoski Mayara E Carneiro Elaine C Lengowski Felipe Z Schardosin Graciela I Bolzon de Muñiz 《Southern Forests》2015,77(4):243-247
The correct identification of pine species is necessary for proper application of wood in forest?based industries, since the quality of each species’ wood depends on factors intrinsic to the material. The aim of this study was to evaluate the potential use of near?infrared and visible spectroscopy in the discrimination of pine species planted in southern Brazil. Needles of Pinus clausa, P. glabra, P. kesiya, P. oocarpa, P. palustris, P. pseudostrobus, P. rigida, P. roxburghii and P. serotina were collected from experimental plantations located in the region of Rio Negro, Paraná, Brazil. The needles were dried and milled for analysis. The evaluation was performed with a spectral range of 400–750?nm (visible) and 1 000–2 500?nm (near?infrared). Analysis using the visible spectra resulted in two principal components explaining 95% of the variation between the needle samples. In the near?infrared analysis, it was possible to discriminate between all nine pine species studied using only two principal components, where the first explained 99% of the variation between species. Spectroscopy based on needles can be used for pine species discrimination, using the original data without mathematical treatment, in southern Brazil. 相似文献
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Luiz Felipe Ramos Carvalho Cristiano Barros de Melo Luiza Seixas Concepta McManus 《Tropical animal health and production》2014,46(3):495-502
The aim of this study was to define the differences between the Brazilian states that export and do not export meat to the European Union (EU) and to identify the variables that are important to meet the export requirements. Infrastructure and computerization of the control of animal transit in Brazil that impact on regional health status were evaluated and linked to other variables such as status for foot and mouth disease (FMD) and qualification to export meat to EU. Variables related to transit control of bovines implemented by the state agencies of animal health and inspection in each Brazilian state were evaluated. Using a discriminant analysis, four variables were selected that explained the variation between Brazilian states that were “free” and “not free” of FMD while another four were selected to explain the variation between the zones “approved” and “not approved” to export meat to the EU, including number of official veterinarians, total transit of bovines and buffaloes, total number of animal transit certificates issued for bovine and buffaloes at the state or zone level, and total number of municipalities in the state or zone. It was possible to correctly discriminate between “free” and “not free” FMD states or zones. Variables related to animal transit are important in assessing the state for the classification of animal health situation and for EU approval for the exportation of meat. 相似文献
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Inmaculada Moreno Julio Álvarez Nerea García Santiago de la Fuente Irene Martínez Eloy Marino Alfredo Toraño Joaquin Goyache Felipe Vilas Lucas Domínguez Mercedes Domínguez 《Veterinary parasitology》2014,199(3-4):264-267
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections. 相似文献