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The flavor of eight samples of commercial strawberry yogurt was studied by Free-Choice Profile analysis (FCP). Generalized Procrustes Analysis (GPA) applied to FCP allowed differentiation between samples and highlighted flavor attributes responsible for the observed differences. The relation between sensory and physicochemical datasets was studied by means of GPA. Those samples with higher carbohydrate content were perceived as sweeter, having stronger strawberry flavor, and with more dairy and yogurt flavors. Samples with higher titratable acidity, ash and protein content were perceived as more acidic and higher in intensity of "faulty" or "defective" flavors. Higher moisture content was associated with lower intensity of "dairy" flavors (creamy, dairy, and yogurt) and greater intensity of rancid flavor. It is concluded that, though not often used to this end, GPA is a suitable method to study the relationship of sensory and instrumental measurements.  相似文献   
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Abstract: The ‘perleidiform’Mendocinichthys and Pseudobeaconia from the Potrerillos and Santa Clara Abajo formations (Upper Triassic; Argentina) are reviewed. Mendocinichthys has been known from a review of this species that is not based on the type material, but on referred specimens in the American Museum of Natural History. However, those specimens are found here to represent a new species of Pseudobeaconia, Pcelestae sp. nov. Consequently, Mendocinichthys is restricted here to the type material and, within it, to the only specimen that clearly represents a distinct taxon and is thus designated lectotype. We further performed a cladistic analysis and propose a new family, Pseudobeaconiidae for these two South American Triassic genera, which is mainly characterized by the presence of an incomplete dorsal ridge of spine‐like scales between the skull and the dorsal fin, and scales with straight posterior border, an elevated central region and marginal concentric ridges of ganoine. The cladistic analysis further indicates the existence of some lineages endemic to certain areas of Gondwana and Europe. Pseudobeaconia celestae sp. nov. represents the first record of Pseudobeaconia in the Cacheuta sub‐basin of the Cuyana Basin. The genus was previously known from the Santa Clara sub‐basin of the Cuyana Basin only, and the new record confirms the previous hypothesis of correlation between the sedimentary infilling of these sub‐basins.  相似文献   
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The cotton aphid ( Aphis gossypii Glover) is a cosmopolitan pest species consisting of various host plant-associated lineages that appear to have different patterns of insecticide resistance, electrophoretic banding, and reproductive output across alternative host species. Debate continues as to whether these differences represent intraspecific variation or indicate a complex of cryptic or sibling species. We studied the host plant-related ecology of two asexual lineages of A. gossypii associated with the families Malvaceae and Cucurbitaceae, respectively, in particular the host plant finding and acceptance processes of the alate forms. The two lineages proved to be differentiated across host plants in terms of: (1) their landing and settling behaviour, nymphal production rate, and subsequent colony establishment (i.e. nymphal survival and development) and (2) their sensory abilities in relation to host plant-derived odours. Furthermore, genetic structuring according to host plant type was detected using the gene for elongation factor 1-α. The magnitude of the genetic differentiation across lineages was low, perhaps indicating a relatively recent divergence. The results demonstrate: (1) the presence of (at least) two cryptic species within the current definition of A. gossypii , as anticipated in previous studies, and (2) the practicalities of using a multidisciplinary approach to understanding the 'limits' of asexual species. If sexuals can be generated from each of these lineages, this conclusion will be open to further testing.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 503–519.  相似文献   
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1. Immune priming refers to improved protection of the host after a second encounter with the same parasite or pathogen. This phenomenon is similar to that of adaptive immunity in vertebrates. 2. There is evidence to suggest that this improved protection can be species/strain‐specific and can protect organisms for a lifetime. These two attributes, along with a biphasic immune response, are essential characteristics of immune priming and form the basis for the effectiveness of resistance to parasites and pathogens. 3. This paper considers the effect of immune priming within and across generations, the influence of a heterologous challenge during immune priming and the importance of testing the immune response with natural pathogens. 4. The analysis presented takes into account the multifaceted nature of the invertebrate immune response. The lack of evidence suggesting that the bacterial microbiome plays a complementary role in the immune priming outcome is discussed. 5. Finally, the cost of immune priming is explored. This is a poorly investigated issue, which could help to explain why there is a paucity of evidence in support of immune priming.  相似文献   
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We isolated 11 polymorphic microsatellite markers from Acacia mellifera, a savannah woodland tree in sub‐Saharan Africa and southern Arabia. The loci were screened for polymorphism using 48 Kenyan individuals. Allelic diversity ranged from three to 19 per locus and the polymorphic information content varied from 0.287 to 0.893. These loci will be useful in studies of genetic structure, gene flow and breeding systems.  相似文献   
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We describe the oldest Paucituberculata marsupials, from the La Barda and Las Flores localities (Argentina; Late Palaeocene, and Early–Middle Eocene), as well as from the Itaboraí Basin (Brazil; Late Palaeocene). The new taxa are represented by very scarce, although well‐preserved, dental remains. A parsimony analysis was performed in order to evaluate the phylogenetic affinities of these taxa. Representatives of both Riolestes capricornicus gen. et sp. nov. and Bardalestes hunco gen. et sp. nov. appear to be basal paucituberculatans, and their molar features give clues on the early evolution of the representatives of this order. Within the Paucituberculata we recognize two major clades: Caenolestoidea and Palaeothentoidea. We conclude that ‘pseudodiprotodont’ marsupials of the traditional literature (i.e. Polydolopimorphia + Paucituberculata) do not form a natural group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 867–884.  相似文献   
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