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11.
Marina Vianna Braga Paloma Martins Mendonça Rodrigo Rocha Barbosa Gary James Blomquist Shênia Patricia Corrêa Novo Juliana da Matta Furniel Dutra 《Journal of Natural History》2016,50(21-22):1381-1388
Insect puparia were found adhered to the ribs and other tissues in the abdominal cavity of a natural male mummy found in Itacambira (State of Minas Gerais, Brazil) dating to the Colonial Period. They were collected for identification by scanning electron microscopy, and for comparison of several morphological features with those described in the literature. The puparia were found open and dorsoventrally flattened, making it difficult to visualize the dorsal projections. The tegument is covered by tapered spines and contains rows of small tubercles on the dorsal and lateral regions of the puparium. The posterior spiracle consists of four parallel openings arranged in pairs. These results are indicative that the specimens belong to the species Megaselia scalaris (Loew, 1866) (Diptera: Phoridae). Additionally, cuticular hydrocarbons of the puparia were analysed by gas chromatography coupled to mass spectrometry and compared with the profile of M. scalaris reared in the laboratory. 相似文献
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Paulo Mateus Martins-Sobrinho Winny Gomes de Oliveira Silva Elizandra Gomes dos Santos Geraldo Jorge Barbosa de Moura Jaqueline Bianque de Oliveira 《Journal of Natural History》2017,51(27-28):1639-1648
Despite the fact that Brazil is the most-studied country regarding helminths of amphibians, only around 8% of Brazilian anurans have had at least one study made of their helminth fauna. Therefore, the aim of this study was to describe the helminth community of nine species of Atlantic Rainforest anurans of two different families, eight of them with no previous study, and six of which are endemic to Brazil. The analysed hosts for their parasites were: Dendropsophus minutus (n = 48), Scinax auratus (n = 36), D. branneri (n = 33), D. elegans (n = 26), Hypsiboas albomarginatus (n = 22), Pithecopus nordestinus (n = 19), D. decipiens (n = 12), D. haddadi (n = 11) and S. x-signatus (n = 11). A total of 781 helminths were collected from 106 (48.6%) of 218 analysed hosts, 656 Centrorhyncus sp. cystacanths and 125 nematodes: 76 adults (25 Cosmocerca sp.; three Cosmocerceidae gen. sp.; 20 Cosmocerca parva, 20 Cosmocercella phyllomedusae, five Aplectana sp., two Oswaldocruzia sp. and one Rhabdias sp.), 43 encysted larvae (nine Porrocaecum sp. and 34 Brevimulticaecum sp.) and six Physaloptera sp. larvae. Anurans may display many roles within the helminth life cycles, as they act as both predator and prey to a wide variety of animals. Consequently, we have found helminths that use anurans as definitive, intermediate and paratenic hosts. Opposing other surveys in which nematodes are the most prevalent and abundant parasites, acanthocephalans were the most prevalent taxa. These findings highlight the lack of knowledge regarding the helminth fauna of anurans and reveal many gaps with respect to their infection patterns in amphibians. 相似文献
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Unexpectedly high rate of de novo constitutional t(11;22) translocations in sperm from normal males 总被引:7,自引:0,他引:7
Junction fragments from the constitutional t(11;22)(q23;q11) translocation have previously been cloned and sequenced. Here we report a high incidence of translocation-specific PCR products in sperm DNA from normal individuals. Somatic DNA from these and other normal individuals or from people with chromosomal breakage syndromes do not yield PCR junction fragments, indicating that this translocation originates during meiosis. 相似文献
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F. E. Vega P. Barbosa H. L. Kuo-Sell D. B. Fisher T. C. Nelsen 《Cellular and molecular life sciences : CMLS》1995,51(3):293-299
Insect-transmitted plant pathogens can have positive, negative or no effects on the vector insect. Effects could be direct (caused by the pathogen) or indirect (mediated by changes in the plant). Pathogen effects on non-vector insects are less well known.Peregrinus maidis (Ashmead) (Homoptera: Delphacidae), an insect that is not a vector of the corn stunt spiroplasma (CSS), weighed less 15 days after feeding on CSS-infected corn plants relative to insects feeding on healthy corn plants. Fecundity of non-vector insects that were removed from diseased plants was higher than for insects coming from healthy plants. ForDalbulus maidis (DeLong & Wolcott) (Homoptera: Cicadellidae), an insect that transmits CSS, there were no differences in weight, longevity, eggs per day, weekly or total fecundity after feeding on healthy or on CSS-infected corn plants. Significant differences in some phloem amino acids were detected between healthy and CSS-infected plants. Infected plants also showed an increased phloem acidity as disease symptoms progressed. Feeding on CSS-infected corn plants by an insect that does not vector the pathogen infecting the plant can have favorable consequences as evidenced by an increased fecundity.Scientific aritcle no. 8819, contribution no. A-6605 of the Maryland Agricultural Experiment Station. 相似文献
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Emanuel Parzen 《Journal of forecasting》1982,1(1):67-82
Methods of time series forecasting are proposed which can be applied automatically. However, they are not rote formulae, since they are based on a flexible philosophy which can provide several models for consideration. In addition it provides diverse diagnostics for qualitatively and quantitatively estimating how well one can forecast a series. The models considered are called ARARMA models (or ARAR models) because the model fitted to a long memory time series (t) is based on sophisticated time series analysis of AR (or ARMA) schemes (short memory models) fitted to residuals Y(t) obtained by parsimonious‘best lag’non-stationary autoregression. Both long range and short range forecasts are provided by an ARARMA model Section 1 explains the philosophy of our approach to time series model identification. Sections 2 and 3 attempt to relate our approach to some standard approaches to forecasting; exponential smoothing methods are developed from the point of view of prediction theory (section 2) and extended (section 3). ARARMA models are introduced (section 4). Methods of ARARMA model fitting are outlined (sections 5,6). Since‘the proof of the pudding is in the eating’, the methods proposed are illustrated (section 7) using the classic example of international airline passengers. 相似文献
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Increasing destructiveness of tropical cyclones over the past 30 years 总被引:38,自引:0,他引:38
Theory and modelling predict that hurricane intensity should increase with increasing global mean temperatures, but work on the detection of trends in hurricane activity has focused mostly on their frequency and shows no trend. Here I define an index of the potential destructiveness of hurricanes based on the total dissipation of power, integrated over the lifetime of the cyclone, and show that this index has increased markedly since the mid-1970s. This trend is due to both longer storm lifetimes and greater storm intensities. I find that the record of net hurricane power dissipation is highly correlated with tropical sea surface temperature, reflecting well-documented climate signals, including multi-decadal oscillations in the North Atlantic and North Pacific, and global warming. My results suggest that future warming may lead to an upward trend in tropical cyclone destructive potential, and--taking into account an increasing coastal population--a substantial increase in hurricane-related losses in the twenty-first century. 相似文献
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Rodrigo Rocha Barbosa Marina Vianna Braga Gary James Blomquist Margareth Maria de Carvalho Queiroz 《Journal of Natural History》2017,51(25-26):1491-1498
Cuticular hydrocarbons (CHs) contain complex mixtures of components that cover the surface of all insects to restrict water loss, and in many species function in chemical communication. The complex mixtures have been used as a chemotaxonomic tool since the 1970s. The majority of CH components can be identified by gas chromatography-mass spectrometry (GC-MS), allowing hydrocarbon profiles to be used as chemotaxonomic characters, which can differentiate insect species, including cryptic species. The present study used GC-MS for the identification of CHs of males and females of three species of calliphorids: Cochliomyia macellaria (Fabricius), Hemilucilia segmentaria (Fabricius) and Lucilia cuprina (Wiedmann), A comparison of the chromatographic profiles from the three species allows them to be readily separated. Hydrocarbons identified from the three species contain 23 to 37 carbons and include n-alkanes, methyl-branched alkanes and alkenes. The most abundant compound for both sexes of C. macellaria was n-heptacosane, while for H. segmentaria it was 2-methyltriacontane; for L. cuprina, however, the most abundant compound was hentriacontene for females and nonacosene for males. The results obtained in this study are important for the establishment of a database to be used in chemotaxonomy of sanitarily and forensically important insects. 相似文献
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In this paper we propose a new method for evaluating image recording strategies for limited angle tomography.In limited angle tomography exact three-dimensional(3-D) reconstruction is not achievable.With this method a metric for the reachable reconstruction quality by defined X-ray source trajectories is calculated.The result of our method is independent of reconstruction algorithms.Our approach is based on the gradients of the scanned volume and their grade of determinability.Compared to simulated reconstr... 相似文献