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991.
North American glyptodonts originated from South American ancestors during the Great American Biotic Interchange no later than early Blancan North American Land Mammal Age (NALMA). A substantial expansion in population samples from the late Blancan 111 Ranch fauna of southeastern Arizona, several late Blancan faunas in New Mexico, and the early Blancan–Irvingtonian faunas of Guanajuato, Mexico, permit, analysis of sexual dimorphism and ontogeny of Glyptotherium texanum Osborn, 1903. Growth of carapacial osteoderms was allometric, including changes of the external sculpturing. Overall anatomy of the carapace changed with growth, with development of distinctive pre-iliac and post-iliac regions in lateral profile of adults. Skulls of adults possess a unique boss on the anterior surface of the descending process of the zygomatic arch that is not present in juveniles. Sexual dimorphism involves differences in anatomy of lateral and posterior osteoderms. Glyptotherium arizonae Gidley, 1926, is a junior synonym of G. texanum. The temporal distribution of G. texanum extends from early Blancan NALMA to Irvingtonian NALMA, with geographical distribution from Central America and Mexico to southern United States.  相似文献   
992.
Here, we perform an ecomorphological study on the major bones (humerus, radius, and ulna) of the carnivoran forelimb using three-dimensional geometric morphometrics. More specifically, we test the association between forelimb morphology and predatory behavior. Our results suggest that the main morphological adaptions of carnivorans to different predatory behaviors relate to: (i) the capacity to perform long and efficient runs as in pounce/pursuit and pursuit predators; (ii) the ability to maneuver as in occasional predators; and (iii) the capacity to exert and resist large loads as in ambushing predators. We used borophagine canids as a case study, given the controversy on the predatory behavior of this extinct subfamily. Our results indicate that borophagines displayed a limited set of adaptions towards efficient running, including reduced joint mobility in both the elbow and the wrist, aspects in which they resemble the living canids. Furthermore, they had forelimbs as powerful as those of the extant ambushing carnivorans (i.e., most felids). This combination of traits suggests that the predatory behavior of borophagines was unique among carnivorans, as it was not fully equivalent to any of the living species.  相似文献   
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Separation of the heterogeneous lignin macromolecule in fractions with increased homogeneity, as well as different structural (molar mass) and functional (hydroxy groups, ‐OH) features is important in terms of its use as a chemical building block. For this purpose, three thermal separation techniques were investigated and compared: solvent extraction, successive precipitation and ultrafiltration. One important issue in this context is the utilization of organic solvents with low boiling points to ensure a simple and efficient recovery. In addition to a softwood Kraft lignin (Indulin AT) as reference lignin, two sulfur‐free Organosolv lignins from short rotation coppice (“poplar with bark”) and from the energy grass Miscanthus × gigantheus were investigated. The lignins were separated into low, medium and high molecular weight fractions. Due to the different initial structural features and the associated varying solubility properties in such lignins, different organic solvents were needed for dissolution and precipitation of the individual lignin fractions. The polarity of the used solvent is one key factor regarding the yield of the soluble fraction and the success of molecular sorting into low, medium, and high molecular weight. Further structural features, for example the aliphatic OH‐group content increased with rising molecular weight of poplar, miscanthus, and Kraft lignin from minimum 0.72, 0.3, and 1.6 mmol/g to maximum 2.4, 1.6, and 2.8 mmol/g, respectively. The number of phenolic OH‐groups decreased from maximum 3.8, 4.3, and 4.2 to minimum 1.4, 2.7, and 2.9, respectively. The presented work illustrate options regarding the molecular sorting of several lignin types with three thermal techniques into fractions differing in key properties (yield, molecular weight, polydispersity, functional groups) for material applications.  相似文献   
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Journal of Physiology and Biochemistry - Aerobic exercise training induces a unique cardioprotective phenotype, but it is becoming clear that it does not promote the same structural, functional,...  相似文献   
998.
BackgroundCandida albicans is the main agent that causes vulvovaginal candidiasis. Resistance among isolates to azole antifungal agents has been reported.AimsDue to the well-known antifungal potential of curcumin, the purpose of this work was to evaluate the in vitro anticandidal activity of curcumin and its effect in the treatment of experimental vulvovaginal candidiasis.MethodsThe anticandidal activity of curcumin was investigated against eight Candida strains by the broth microdilution assay, and its mechanism of action was evaluated by testing the binding to ergosterol. Then, the effect of curcumin in the treatment of vulvovaginal candidiasis was evaluated in an immunosuppressed, estrogen treated rat model.ResultsCurcumin showed minimum inhibitory concentration values of 125–1000 μg/ml, and the best result was observed against Candida glabrata. The compound was shown to be able to bind to the ergosterol present in the membrane, event that may be the mechanism of action. In addition, in the in vivo model of vulvovaginal candidiasis with C. albicans, treatments reduced the vaginal fungal burden in infected rats after seven days of treatment with different doses.ConclusionsCurcumin could be considered a promising effective antifungal agent in the treatment of vulvovaginal candidiasis.  相似文献   
999.
The divergence date and ancestral distributional area of the psocid subfamily Speleketorinae, which includes taxa with reversed genitalia (female penis and male vagina of Afrotrogla and Neotrogla, tribe Sensitibillini), were estimated. The most basal divergence of the subfamily (between the North American Speleketor and the tribe Sensitibillini) was estimated to have occurred according to the separation between the North American continent and Gondwana, ca. 175 Ma. The most basal divergence of Sensitibillini (between African Afrotrogla + Sensitibilla and Brazilian Neotrogla) was estimated to have occurred according to the split of West Gondwana (separation between the African and South American continents), ca. 127 Ma. The biome of the ancestral distributional area of Sensitibillini (inland of West Gondwana) is believed to be arid to semi‐arid, which might strengthen the reversed sexual selection and then facilitate the origin of preadaptive features related to the evolution of a female penis. All extant Sensitibillini species inhabit carbonatic caves, but geological evidence suggested independent shifts of these genera to the carbonatic cave habitat in the Tertiary/Quaternary.  相似文献   
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