Loading...
4 results
Search Results
Now showing 1 - 4 of 4
- Sex determination from the femur in Portuguese populations with classical and machine-learning classifiersPublication . Curate, Francisco; Umbelino, Cláudia; Perinha, A.; Nogueira, C.; Silva, A. M.; Cunha, E.The assessment of sex is of paramount importance in the establishment of the biological profile of a skeletal individual. Femoral relevance for sex estimation is indisputable, particularly when other exceedingly dimorphic skeletal regions are missing. As such, this study intended to generate population-specific osteometric models for the estimation of sex with the femur and to compare the accuracy of the models obtained through classical and machine-learning classifiers. A set of 15 standard femoral measurements was acquired in a training sample (100 females; 100 males) from the Coimbra Identified Skeletal Collection (University of Coimbra, Portugal) and models for sex classification were produced with logistic regression (LR), linear discriminant analysis (LDA), support vector machines (SVM), and reduce error pruning trees (REPTree). Under cross-validation, univariable sectioning points generated with REPTree correctly estimated sex in 60.0e87.5% of cases (systematic error ranging from 0.0 to 37.0%), while multivariable models correctly classified sex in 84.0-92.5% of cases (bias from 0.0 to 7.0%). All models were assessed in a holdout sample (24 females; 34 males) from the 21st Century Identified Skeletal Collection (University of Coimbra, Portugal), with an allocation accuracy ranging from 56.9 to 86.2% (bias from 4.4 to 67.0%) in the univariable models, and from 84.5 to 89.7% (bias from 3.7 to 23.3%) in the multivariable models. This study makes available a detailed description of sexual dimorphism in femoral linear dimensions in two Portuguese identified skeletal samples, emphasizing the relevance of the femur for the estimation of sex in skeletal remains in diverse conditions of completeness and preservation. (C) 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
- Metacarpal cortical bone loss and osteoporotic fractures in the Coimbra Identified Skeletal CollectionPublication . Curate, Francisco; Perinha, Andreia; Silva, Ana Maria; Cunha, Eugenia; Umbelino, Cláudia; Nogueira, CatarinaThere has been considerable progress in recent years in our understanding of the patterns of cortical bone loss in the second metacarpal in archeological skeletal samples. Nevertheless, cortical data from reference skeletal collections are insufficient, and the possible connection of metacarpal cortical parameters with osteoporotic fractures has not been thoroughly addressed. As such, this article aims to identify and explain sex-specific and age-associated metacarpal cortical bone loss in a large sample (N = 302
- Cortical bone loss in a sample of human skeletons from the Muge Shell middensPublication . Umbelino, Cláudia; Curate, Francisco; Perinha, Andreia; Ferreira, Teresa; Cunha, Eugenia; Bicho, NunoThe Muge shell middens of Cabeco da Arruda, Cabeco da Amoreira and Moita do Sebastiao (central Portugal) have been key sites of archaeological research for 150 years, possibly working as residential sites occupied by semi-sedentary communities during the final Mesolithic. The purposes of this article include the biocultural assessment of metacarpal cortical bone fragility and its associations with age at death, sex and osteoporotic fractures in the Portuguese Mesolithic, as well as a diachronic comparison of cortical bone health in Mesolithic (N = 34) and modern reference (N = 219) samples. Cortical bone at the Muge shell middens displays age and sex-specific trajectories of periosteal apposition and endosteal bone loss, most likely associated with hormonal and behavioural/cultural influences. Metacarpal endocortical bone loss seems to increase with age at death in females, with a simultaneous expansion of the diaphysis. The overall pattern of cortical bone health is similar to the pattern observed in a reference skeletal collection, but elderly women from Muge seem to lose less cortical bone than late twentieth century counterparts from Coimbra. Two older males exhibited vertebral compression fractures, but only one is possibly related with bone fragility.
- Resilience, replacement and acculturation in the Mesolithic/Neolithic transition: The case of Muge, central PortugalPublication . Bicho, Nuno; Cascalheira, João; Gonçalves, Célia; Umbelino, Cláudia; García-Rivero, Daniel; André, LinoEvidence for the first Neolithic population in central Portugal dates to as early as c. 7600 cal BP. These first farmers were exogenous groups arriving to the Atlantic coast from the Mediterranean Sea. For a few centuries there seems to have occurred an overlap in the region between the Mesolithic Muge huntergatherers and the regional early Neolithic populations. While the trajectory of these first farmers seems to be well established, the fate of the Mesolithic populations is unknown and in generally assumed as resulting in extinction. The recent results from research in the Muge Mesolithic shellmounds (Tagus valley) with the new recovery of various loci with Neolithic occupations including human burials, human DNA, and Strontium analyses seem to indicate evidence of cultural and genetic integration between the Mesolithic and Neolithic populations. This paper will focus on the Mesolithic-Neolithic transition in Portuguese Estremadura and examines the hypothesis that human resilience promoted the cultural and biological integration of the Mesolithic groups into the new exogenous Neolithic communities in central Portugal. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.