1,339 research outputs found

    The Great American Biotic Interchange revisited: a new perspective from the stable isotope record of Argentine Pampas fossil mammals

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    This study aims at assessing resource and habitat use, niche occupation and trophic interactions from a stable isotope perspective on fossil mammals from the Argentine Pampas during the Great American Biotic Interchange (GABI). We present stable isotope data of more than 400 samples belonging to 10 mammalian orders and spanning a temporal range from ~9.5 Ma to ~12 ky. Rodents, notoungulates and pilosians record an increase in the consumption of C4 plants, whereas litopterns and cingulates show δ13C values that remain mostly within a C3-dominated diet. Our stable isotope data indicates that the expansion of C4 vegetation opened up new niche opportunities, probably alleviating resource competition among endemic taxa. Gomphothere, equid and camelid δ13C records show a broad variability pointing to consumption of C3 and mixed C3-C4 vegetation. This flexible dietary behavior may have facilitated the successful settlement of immigrant groups in South America. In the case of carnivorous taxa, Late Miocene pre-GABI endemic sparassodonts consumed prey from C3 environments, whereas immigrant carnivorans preferred prey from mixed C3-C4 areas. Our research contributes to the study of the GABI from a different perspective as stable isotope records permit to characterize, from a (semi)quantitative standpoint, ecological traits within extinct fauna

    Consistency of a nonword repetition task to discriminate children with and without developmental language disorder in Catalan-Spanish and European Portuguese speaking children

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    Nonword repetition has been proposed as a diagnostic marker of developmental language disorder (DLD); however, the inconsistency in the ability of nonword repetition tasks (NRT) to identify children with DLD raises significant questions regarding its feasibility as a clinical tool. Research suggests that some of the inconsistency across NRT may be due to differences in the nature of the nonword stimuli. In this study, we compared children’s performance on NRT between two cohorts: the children in the Catalan–Spanish cohort (CS) were bilingual, and the children in the European Portuguese cohort (EP) were monolingual. NRT performance was assessed in both Spanish and Catalan for the bilingual children from Catalonia-Spain and in Portuguese for the monolingual children from Portugal. Results show that although the absolute performance differed across the two cohorts, with NRT performance being lower for the CS, in both Catalan and Spanish, as compared to the EP cohort in both, the cut-points for the likelihood ratios (LH) were similar across the three languages and mirror those previously reported in previous studies. However, the absolute LH ratio values for this study were higher than those reported in prior research due in part to differences in wordlikeness and frequency of the stimuli in the current study. Taken together, the findings from this study show that an NRT consisting of 3-, 4-, and 5-syllable nonwords, which varies in wordlikeness ratings, when presented in a random order accurately identifies and correctly differentiates children with DLD from TD controls the child is bilingual or monolingual.This research was funded by the National Institute on Deafness and Other Communication Disorders (NIDCD) Grant [R0105263] awarded to Dr. Evans, from The National Institute of Child Health and Human Development (NICHD) Grant [P30HD03352] awarded to the Waisman Center, The University of Wisconsin Madison; by the Ministerio de Economía y Competitividad Grant [2016EDU2016-75368-P/BES-2014-070511] awarded from Dr. Andreu and from the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) de la Generalitat de Catalunya [2017SGR387] awarded to the Grup de Recerca en Cognició i Llenguatge (UOC-UB); by the CIEd—Research Centre on Education, Institute of Education, University of Minho, projects [UIDB/01661/2020] and [UIDP/01661/2020], through national funds of FCT/MCTES-PT

    Gregariousness in the giant sloth Lestodon (Xenarthra): multi-proxy approach of a bonebed from the Last Maximum Glacial of Argentine Pampas

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    Megamammals constituted an important component in the Pleistocene faunal communities of South America. Paleobiological and paleoecological studies involving different megamammal taxa have increased significantly in the last years, but there are still several poorly-known issues of its life history. In this work, we analyze an assemblage composed of 13 individuals of different ontogenetic stages, and possibly different sex, belonging to the giant ground sloth Lestodon armatus (Xenarthra, Folivora), recovered from Playa del Barco site (Pampean Region, Argentina). A dating of 19,849 years Cal BP allows assigning this assemblage to a period of the MIS (Marine Isotope Stage) 2 related to the end of the Last Glacial Maximum. Based on multiple lines of research (e.g. taphonomy, paleopathology, osteohistology, isotopy), we interpret the origin of the assemblage and diverse paleobiological and paleoecological aspects (e.g. social behavior, ontogenetic changes, sexual dimorphism, diseases, resource and habitat use, trophic relationships) of L. armatus. Evidence suggests that the assemblage was formed by a local single event of catastrophic mortality, which affected different members of a social group. This record represents the first accurate evidence of gregariousness for this ground sloth, providing new data on a poorly-known behavior among extinct Folivora

    Physical Education Program for university students with intellectual disabilities from service-learning methodology

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    La experiencia de aprendizaje-servicio que se presenta a continuación se ha desarrollado on el alumnado del Grado de Ciencias de la Actividad Física y el Deporte (9 materias) y el Grado de Magisterio en Educación Primaria con Mención en Educación Física (1 asignatura) de la Universidad Autónoma de Madrid11. La finalidad principal que se persigue es desarrollar las competencias profesionales a través del aprendizaje experiencial, ofreciendo un servicio comprometido y responsable al alumnado universitario con discapacidad intelectual que participa en el Programa Promentor. En concreto, el servicio prestado persigue desarrollar los aprendizajes motrices del alumnado, así como una actitud positiva para la ocupación activa del ocio y la adquisición de hábitos de práctica saludable. Esta metodología requiere llevar a cabo unos protocolos para orientar los procesos de intervención del alumnado del Grado, a través de una serie de acciones formativas sistematizadas y supervisadas por el profesorado universitario (asambleas, diseño e implementación de sesiones, etc.). La evaluación de la experiencia desarrollada se realiza a partir de la información recopilada de los diferentes agentes implicados en el proceso (profesorado y alumnado de Grado y de Promentor)A service-learning experience has been developed with the students of Sport Sciences and Physical Activity Degree (9 subjects) and Primary Education with Physical Education Specialty Degree (1 subject) at Autonomous University of Madrid. The main aim followed is to develop their professional competences through experiential learning offering a committed and responsible service to university students with intellectual disabilities who participate in the Promentor Program. Specifically, the service provided aims to develop student motor skills, as well as a positive attitude for the active occupation of leisure and the acquisition of healthy practice habits. This methology requires carried out some protocols to guide the interventions of Degree students, through some systematized and supervised formative actions by university teachers (conferences, design and implementation of sessions, etc). The experience assessment is carried out with the information gathered from the different agents involved in the process (teachers and Degree and Promentor students

    In Vivo Tumor Targeting and Imaging with Engineered Trivalent Antibody Fragments Containing Collagen-Derived Sequences

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    There is an urgent need to develop new and effective agents for cancer targeting. In this work, a multivalent antibody is characterized in vivo in living animals. The antibody, termed “trimerbody”, comprises a single-chain antibody (scFv) fragment connected to the N-terminal trimerization subdomain of collagen XVIII NC1 by a flexible linker. As indicated by computer graphic modeling, the trimerbody has a tripod-shaped structure with three highly flexible scFv heads radially outward oriented. Trimerbodies are trimeric in solution and exhibited multivalent binding, which provides them with at least a 100-fold increase in functional affinity than the monovalent scFv. Our results also demonstrate the feasibility of producing functional bispecific trimerbodies, which concurrently bind two different ligands. A trimerbody specific for the carcinoembryonic antigen (CEA), a classic tumor-associated antigen, showed efficient tumor targeting after systemic administration in mice bearing CEA-positive tumors. Importantly, a trimerbody that recognizes an angiogenesis-associated laminin epitope, showed excellent tumor localization in several cancer types, including fibrosarcomas and carcinomas. These results illustrate the potential of this new antibody format for imaging and therapeutic applications, and suggest that some laminin epitopes might be universal targets for cancer targeting

    An S-Locus Independent Pollen Factor Confers Self-Compatibility in 'Katy' Apricot

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    Loss of pollen-S function in Prunus self-compatible cultivars has been mostly associated with deletions or insertions in the S-haplotype-specific F-box (SFB) genes. However, self-compatible pollen-part mutants defective for non-S-locus factors have also been found, for instance, in the apricot (Prunus armeniaca) cv. 'Canino'. In the present study, we report the genetic and molecular analysis of another self-compatible apricot cv. termed 'Katy'. S-genotype of 'Katy' was determined as S1S2 and S-RNase PCR-typing of selfing and outcrossing populations from 'Katy' showed that pollen gametes bearing either the S-1- or the S-2-haplotype were able to overcome self-incompatibility (SI) barriers. Sequence analyses showed no SNP or indel affecting the SFB1 and SFB2 alleles from 'Katy' and, moreover, no evidence of pollen-S duplication was found. As a whole, the obtained results are compatible with the hypothesis that the loss-of-function of a S-locus unlinked factor gametophytically expressed in pollen (M'-locus) leads to SI breakdown in 'Katy'. A mapping strategy based on segregation distortion loci mapped the M'-locus within an interval of 9.4 cM at the distal end of chr.3 corresponding to similar to 1.29 Mb in the peach (Prunus persica) genome. Interestingly, pollen-part mutations (PPMs) causing self-compatibility (SC) in the apricot cvs. 'Canino' and 'Katy' are located within an overlapping region of similar to 273 Kb in chr.3. No evidence is yet available to discern if they affect the same gene or not, but molecular markers seem to indicate that both cultivars are genetically unrelated suggesting that every PPM may have arisen independently. Further research will be necessary to reveal the precise nature of 'Katy' PPM, but fine-mapping already enables SC marker-assisted selection and paves the way for future positional cloning of the underlying gene

    The Menstrual Cycle Modulates Whole-Brain Turbulent Dynamics

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    Brain dynamics have recently been shown to be modulated by rhythmic changes in female sex hormone concentrations across an entire menstrual cycle. However, many questions remain regarding the specific differences in information processing across spacetime between the two main follicular and luteal phases in the menstrual cycle. Using a novel turbulent dynamic framework, we studied whole-brain information processing across spacetime scales (i.e., across long and short distances in the brain) in two open-source, dense-sampled resting-state datasets. A healthy naturally cycling woman in her early twenties was scanned over 30 consecutive days during a naturally occurring menstrual cycle and under a hormonal contraceptive regime. Our results indicated that the luteal phase is characterized by significantly higher information transmission across spatial scales than the follicular phase. Furthermore, we found significant differences in turbulence levels between the two phases in brain regions belonging to the default mode, salience/ventral attention, somatomotor, control, and dorsal attention networks. Finally, we found that changes in estradiol and progesterone concentrations modulate whole-brain turbulent dynamics in long distances. In contrast, we reported no significant differences in information processing measures between the active and placebo phases in the hormonal contraceptive study. Overall, the results demonstrate that the turbulence framework is able to capture differences in whole-brain turbulent dynamics related to ovarian hormones and menstrual cycle stages
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