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321.
Carlos Neto de Carvalho Silvério Figueiredo Fernando Muniz João Belo Pedro P. Cunha Andrea Baucon 《Ichnos》2020,27(3):352-360
AbstractIn his short joint ventures across the world of vertebrate tracks, Richard Bromley recognized the aeolian sands as unsuitable soft substrates for their preservation. Only after his work in the Balearic Islands, a more systematic study of coastal aeolianites worldwide revealed that these depositional systems could preserve a highly important record of behavioural trace fossils for the evolution of vertebrates, especially in the Pleistocene, including extinct megafauna and the escalation of the Homo. Here we describe coastal aeolianites from the upper Pleistocene of SW Iberia, namely SW Portugal and Gibraltar, with trackways, tracks and trampled surfaces of the last elephants in mainland Europe. Photogrammetric 3?D modelling and analysis of the relevant proboscidean track levels allowed revision of and support for previous ichnotaxonomic identification to Proboscipeda panfamilia and behavioural interpretations of the producer. Smaller and very large trackways and footprints attributed to Palaeoloxodon antiquus are described and discussed according to new and recent, but always rare findings. The seeming progressive and definitive extinction of this species towards southern Iberia, following the same pattern for the replacement of the Neanderthals during the last initial Pleniglacial (until ca. 28 ka), suggests evidence for co-evolution. 相似文献
322.
Jorge L. A. Armada Carmen M. L. Barroso Margarida M. C. Lima Jos Augusto P. C. Muniz Hctor N. Seunez 《American journal of primatology》1987,13(3):283-296
The chromosome constitution of Alouatta belzebul was studied with G-, C-, and silver staining. In ten specimens identified as Alouatta belzebul, the chromosome constitution of males (2n = 49) differed from that of females (2n = 50) owing to a Y-autosome translocation. In another single female specimen, probably Alouatta belzebul nigerrima, the diploid chromosome number was also 50, though its karyotype was drastically different from that of Alouatta belzebul belzebul. Chromosome studies, taken together with phenotypic and field observations, suggest that Alouatta belzebul belzebul is phenotypically variable in respect to pelage coloration. This attribute is therefore unreliable for the precise identification of Alouatta belzebul subspecies. Conversely, relatively minor phenotypic differences, allowing for the characterization of subspecies within a same species, coexist with unparalleled, drastic karyotypic divergence. These findings clearly question gross morphological attributes as discriminative characteristics of Alouatta belzebul subspecies. 相似文献
323.
PAWEŁ JAŁOSZYŃSKI 《Systematic Entomology》2011,36(3):470-496
Genera of the Cephennomicrus group of the Cephenniini (Scydmaenitae) are revised, and the following new taxa are described: Trichokrater gen.n. , Trichokrater ekkentros sp.n. (type species of Trichokrater) (Borneo), Cephennococcus gen.n. , Cephennococcus kuchingensis sp.n. (type species of Cephennococcus) (Borneo), Cephennococcus kenyirensis sp.n. (West Malaysia), Cephennococcus crassus sp.n. (Borneo), Cephennococcus minutissimus sp.n. (West Malaysia), Pomphopsilla gen.n. , Pomphopsilla luhya sp.n. (type species of Pomphopsilla) (Kenya) and Pomphopsilla soror sp.n. (Kenya). Unique subcuticular pockets with setose openings on the pronotum of Trurlia and Trichokrater are identified as glandular structures. Enigmatic internal prothoracic cavities are described for the first time in Scydmaeninae (in Cephennococcus, Pomphopsilla and a female of an undescribed genus from Sulawesi); their fine structure and function remain unknown. Parsimony‐based cladistic analysis of the adult morphology of genera of Cephenniini provided robust evidence for a monophyly of the Cephennomicrus group, composed of Cephennomicrus, Cephennula, Lathomicrus, Pomphopsilla, Cephennococcus, Trurlia, Trichokrater and two undescribed Oriental genera known from females only; this distinct and well‐supported lineage is a sister group of Cephennodes + Hlavaciellus. The genus Cephennomicrus represented in the analysis by species belonging to three previously postulated species groups is not monophyletic, and a comprehensive study comprising more taxa is necessary to reclassify this heterogeneous group. 相似文献
324.
To evaluate breastfed infants' responses to scented objects, we videotaped
the facial and bodily reactions of sixty-three infants as they explored, in
succession, three toys that were identical in appearance but different in
their characteristic odor. Two of the toys were scented with odorants
previously shown to be transmitted to human milk, one with ethanol and the
other with vanilla, whereas the third toy was unscented. Each videotape was
subjected to frame-by-frame analysis to measure a variety of behaviors that
are considered either to be exploratory in nature in that they lead to
perceptual information about the object or to reflect the infants' hedonic
reaction. Analyses of these behaviors revealed that the infants looked more
and vocalized less in the presence of the vanilla-scented toy and spent
less time manipulating the ethanol-scented toy when compared with the
unscented toy. Moreover, differential exposure to the odors of ethanol and
vanilla, as indicated by differential consumption of alcohol by a parent or
use of vanilla-scented product by the mother, was related to differential
responses to these odors. These findings suggest that human infants are
able to detect and retain information about the chemical features of their
environment.
相似文献
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327.
Tiffany Weinkopff Camila I. de Oliveira Augusto M. de Carvalho Yazmin Hauyon-La Torre Aline C. Muniz Jose Carlos Miranda Aldina Barral Fabienne Tacchini-Cottier 《PLoS neglected tropical diseases》2014,8(1)
During a blood meal, Lutzomyia intermedia sand flies transmit Leishmania braziliensis, a parasite causing tegumentary leishmaniasis. In experimental leishmaniasis, pre-exposure to saliva of most blood-feeding sand flies results in parasite establishment in absence of any skin damages in mice challenged with dermotropic Leishmania species together with saliva. In contrast, pre-immunization with Lu. intermedia salivary gland sonicate (SGS) results in enhanced skin inflammatory exacerbation upon co-inoculation of Lu. intermedia SGS and L. braziliensis. These data highlight potential unique features of both L. braziliensis and Lu. intermedia. In this study, we investigated the genes modulated by Lu. intermedia SGS immunization to understand their potential impact on the subsequent cutaneous immune response following inoculation of both SGS and L. braziliensis. The cellular recruitment and global gene expression profile was analyzed in mice repeatedly inoculated or not with Lu. intermedia. Microarray gene analysis revealed the upregulation of a distinct set of IFN-inducible genes, an immune signature not seen to the same extent in control animals. Of note this INF-inducible gene set was not induced in SGS pre-immunized mice subsequently co-inoculated with SGS and L. braziliensis. These data suggest the parasite prevented the upregulation of this Lu. intermedia saliva-related immune signature. The presence of these IFN-inducible genes was further analyzed in peripheral blood mononuclear cells (PBMCs) sampled from uninfected human individuals living in a L. braziliensis-endemic region of Brazil thus regularly exposed to Lu. intermedia bites. PBMCs were cultured in presence or absence of Lu. intermedia SGS. Using qRT-PCR we established that the IFN-inducible genes induced in the skin of SGS pre-immunized mice, were also upregulated by SGS in PBMCs from human individuals regularly exposed to Lu. intermedia bites, but not in PBMCs of control subjects. These data demonstrate that repeated exposure to Lu. intermedia SGS induces the expression of potentially host-protective IFN-inducible genes. 相似文献
328.
Cristiane SpagnolFrancisco H.A. Rodrigues Antonio G.B. PereiraAndré R. Fajardo Adley F. RubiraEdvani C. Muniz 《Carbohydrate polymers》2012,87(3):2038-2045
Superabsorbent hydrogel composites based on cellulose nanofibrils and chitosan-graft-poly(acrylic acid) copolymer were developed in this work. The FTIR data showed that the copolymerization and the composite formation reaction were successfully performed. In addition, the XRD pattern indicated that the nanofibrils crystallinity was as high as 90%. A 24−1 fractional factorial design was employed to evaluate the effect of acrylic acid/chitosan molar ratio, crosslinker, initiator, and filler in the swelling capacity of hydrogel composites. By the analysis of variance (ANOVA), including F-test and P-values, it was found that the crosslinker and filler correspond to 40% and 30% of the evaluated response, respectively. The addition of nanofibrils provided faster equilibrium conditions as well as improved the swelling capacity in ca. 100 units, from 381 to 486. SEM images showed that the addition of nanofibrils into the hydrogel matrix increased the averaged-dimension of porous. Finally, the composites showed responsive behavior in relation to pH and salt solution. Such characteristics make these smart materials suitable for several technological applications. 相似文献
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