Testing accuracy in 2D and 3D geometric morphometric methods for cut mark identification and classification

The analysis of bone surface modifications (BSMs) is a prominent part of paleoanthropological studies, namely taphonomic research. Behavioral interpretations of the fossil record hinge strongly upon correct assessment of BSMs. With the significant impact of microscopic analysis to the study of BSMs, multiple authors have discussed the reliability of these technological improvements for gaining resolution in BSM discrimination. While a certain optimism is present, some important questions are ignored and others overemphasized without appropriate empirical support. This specifically affects the study of cut marks. A diversity of geometric morphometric approaches applied to the study of cut marks have resulted in the coexistence (and competition) of different 2D and 3D methods. The present work builds upon the foundation of experiments presented by Maté-González et al. (2015), Courtenay et al. (2017) and Otárola-Castillo et al. (2018) to contrast for the first time 2D and 3D methods in their resolution of cut mark interpretation and classification. The results presented here show that both approaches are equally valid and that the use of sophisticated 3D methods do not contribute to an improvement in accuracy

A comparative study between wmms and tls for the stability analysis of the San Pedro church barrel vault by means of the finite element method

Stability of masonry constructions is highly conditioned by the geometric disposition of its elements due to its low tensile strength and great compressive mechanical properties. Under this framework, this paper attempts to evaluate the suitability of a wearable mobile mapping solution, equipped in a backpack and based on the well-known simultaneous location and mapping paradigm, for the structural diagnosis of historical constructions. To evaluate the suitability of this device, the structural analysis obtained is compared with a high precision terrestrial laser scanner, which is considered as ground truth. The Romanesque church of San Pedro (Becerril del Carpio, Spain) was selected as a study case. This construction, initially conceived in the XIIIth century, has experimented in the past a soil settlement promoting the leaning of the north wall, several plastic hinges in its barrel vault and a visible geometrical deformation. The comparison of both techniques was carried out at different levels: i) an evaluation of the time needed to obtain the point cloud of the church; ii) an accuracy assessment based on the comparison of a terrestrial network using artificial spheres as checkpoints and; iii) an evaluation of the discrepancies, in terms of safety factor and collapse topology, found during the advance numerical evaluation of the barrel vault by means of the finite element method. This comparison places this wearable mobile mapping solution as an interesting tool for the creation of advanced numerical simulations to evaluate the structural stability of historical constructionsJunta de Castilla y León | Ref. SA075P17FEDER | Ref. SOE1/P5/P025

An Evaluation of Landmark-Based Methods to Explore Tooth Score Morphology: A Case Study on Felids and Hyenids

Taphonomic studies aim to identify the modifying agents that intervene in bone assemblages found at archaeopaleontological sites. Carnivores may modify, accumulate, or scavenge skeletal parts inflicting tooth marks, including scores, on the cortical surface. Several works have studied tooth score morphology to discern which carnivore group modified the bone assemblages, achieving different results. In the present study, different methods based on the use of landmarks and semilandmarks have been tested to describe and analyze the score profile cross-sections of spotted and brown hyenas, leopards, and lions. According to our results, the already published seven-landmark method is useful in order to differentiate between carnivore species from different families (e.g., felids and hyenids). Meanwhile, felid species (e.g., leopards and lions) cannot be consistently distinguished using any of the methods tested here. In contrast, hyenid species can be morphologically differentiated. On the other hand, the use of semilandmarks does not generally improve morphological characterization and distinction, but low numbers of landmarks and the inclusion of the score’s deepest point might provide the best results when semi-automatic semilandmark models are preferred to avoid sampling biases.The grant IJC2020-043576-I funded by MCIN/AEI/10.13039/501100011033 and the “European Union NextGenerationEU/PRTR” has been awarded to M.C.A. The grant RYC2021-034813-I funded by MCIN/AEI/10.13039/501100011033 and the European Union “NextGenerationEU”/PRTR has been awarded to M.Á.M.-G. During the development of the present work, J.A. was funded by the Euskal Herriko Unibertsitatea [ESPDOC21/05]. L.A.C. is funded by the Spanish Ministry of Science, Innovation and Universities by an FPI Predoctoral grant PRE2019-089411 associated with project RTI2018-099850-B-I0

Early Pleistocene faunivorous hominins were not kleptoparasitic, and this impacted the evolution of human anatomy and socio-ecology

Humans are unique in their diet, physiology and socio-reproductive behavior compared to other primates. They are also unique in the ubiquitous adaptation to all biomes and habitats. From an evolutionary perspective, these trends seem to have started about two million years ago, coinciding with the emergence of encephalization, the reduction of the dental apparatus, the adoption of a fully terrestrial lifestyle, resulting in the emergence of the modern anatomical bauplan, the focalization of certain activities in the landscape, the use of stone tools, and the exit from Africa. It is in this period that clear taphonomic evidence of a switch in diet with respect to Pliocene hominins occurred, with the adoption of carnivory. Until now, the degree of carnivorism in early humans remained controversial. A persistent hypothesis is that hominins acquired meat irregularly (potentially as fallback food) and opportunistically through klepto-foraging. Here, we test this hypothesis and show, in contrast, that the butchery practices of early Pleistocene hominins (unveiled through systematic study of the patterning and intensity of cut marks on their prey) could not have resulted from having frequent secondary access to carcasses. We provide evidence of hominin primary access to animal resources and emphasize the role that meat played in their diets, their ecology and their anatomical evolution, ultimately resulting in the ecologically unrestricted terrestrial adaptation of our species. This has major implications to the evolution of human physiology and potentially for the evolution of the human brain

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Immune response to exercise in patients with COPD.

Chronic Obstructive Pulmonary Disease (COPD) is increasingly being recognized as systemic rather than only a pulmonary disease. Increasing amounts of activated inflammatory cells, mediators and oxidative stress are not restricted to the local compartment- including airways, lung parenchyma, and pulmonary vasculature - but are also present in the circulation and even more pronounced during exacerbations. The origin and consequences of the systemic inflammation and oxidative stress present in COPD patients remains still to be elucidated. The interactions between exercise stress and the immune system provide a unique opportunity to link basic and clinical physiology and to evaluate the role of underlying stress and immunophysiologic mechanisms. Hypothetically, increased exposure to inflammation and oxidative stress might negatively affect tissues, e.g. skeletal muscles, and thereby play a role in the ongoing and progressive systemic effects of COPD. This thesis aimed to investigate the effects of exercise on the immune response in patients with COPD. It was found that both high and moderate cycling exercise further increases chronic systemic inflammation and oxidative stress in patients with COPD. Especially within a subgroup of patients, namely muscle-wasted COPD patients, the exercise-induced systemic effects are elevated in comparison with healthy individuals and COPD patients without muscle wasting. Even six minutes walking was able to induce systemic responses in these muscle-wasted patients. Furthermore, the severity of muscle wasting was related to the increase of systemic inflammation and oxidative stress, suggesting a causative relation between these systemic effects. Finally, it was shown that cycling with supplemental exercise diminished exercise-induced systemic inflammation and prevented oxidative stress. Mechanistically, both activation of neutrophils and ATP degradation were involved in these effects. In summary, only modest exercise induces a systemic inflammatory and oxidative response in especially muscle-wasted COPD patients. Chronic exposure to these effects might be involved in the ongoing progression of the diseas

Combining machine learning algorithms and geometric morphometrics: A study of carnivore tooth marks

Since the 1980s an intense scientific debate has revolved around the hunting capacities of early hominin populations and the behavioral patterns of carnivores sharing the same ecosystem, and thus competing for the same resources. This debate, commonly known as the hunter-scavenger debate, fostered the emergence of a new research line into the Bone Surface Modifications (BSMs) produced by both taphonomic agents. Throughout the following 20 years, multiple studies concerning the action of carnivores have been developed, with a particular focus on the oldest archaeological sites in East Africa. Recent technological advances applied to taphonomy have provided new insight into carnivore BSMs. A newly developed part of this work relies on Geometric Morphometrics (GMM) studies aimed at discerning carnivore agency through the morphologic characterization of tooth scores and pits. GMM studies have produced promising results, however methodological limitations are still present. This paper presents the first combined application of Machine Learning (ML) algorithms and GMM to the analysis of carnivore tooth marks, generating classification rates of 100% between carnivore species in some cases.This work was developed within the general framework of the Spanish MINECO-FEDER project CGL2015-65387-C3-1-P, the Catalan AGAUR project 2017-SGR-1040, and the URV project 2017-PFR-URV-B2-91

New taphonomic advances in 3D digital microscopy: A morphological characterisation of trampling marks

The concept of equifinality has become one of the greatest difficulties in the field of taphonomy However, new advances in technology have diminished the margins of error in the interpretation of archaeological sites. The use of multivariate statistics and the most recent advances in microscopic analysis of Bone Surface Modifications (BSMs) have enable a less subjective interpretation of site formation processes. Nevertheless, this broader range of methodological approaches also presents some problems. The capacity of laser scanners in processing inconspicuous and superficial cortical alterations, such as trampling marks, has proven to be problematic. This study presents a new advance towards resolving this problem through the use of the HIROX KH-8700 Digital Microscope, whereby detailed digital three-dimensional (3D) reconstructions are able to pick up such minute BSMs. Through the statistical comparison of the David Laser scanner and the HIROX KH-8700 Digital Microscope, this paper contributes to our understanding of said equipment, followed by a significant advance in the characterisation of superficial BSMs. The combination of advanced microscopy and the application of geometric morphometrics highlights a morphological differentiation between two different types of trampling marks, hereby named scratch and graze trampling marks.This work was developed within the general framework of the Spanish MINECO-FEDER project CGL2015-65387-C3-1-P, the Catalan AGAUR project 2017-SGR-1040, and the URV project 2017-PFR-URV-B2-91

Respuestas cardiorrespiratorias y metabólicas ante una sesión de media sentadilla a intensidad de umbral láctico

SIN FINANCIACIÓNNo data (2015