Ann Thorac Surg Short Rep
September 2024
Aneurysms of the superior vena cava are rare vascular malformations of systemic veins. This report presents the case of a 27-year-old woman with an incidental finding of mediastinal shadow widening on the chest roentgenogram that was confirmed by computed tomographic angiography to be a superior vena cava saccular aneurysm >4 cm in diameter. Surgical resection was recommended on the basis of aneurysmal size and shape and was performed through median sternotomy by using cardiopulmonary bypass.
View Article and Find Full Text PDFPETAL (Petawatt Aquitaine Laser) is an ultrahigh-power laser dedicated to academic research that delivers sub-picosecond pulses. One of the major issues of these facilities is the laser damage on optical components located at the final stage. Transport mirrors of the PETAL facility are illuminated under different polarization directions.
View Article and Find Full Text PDFIn the context of the Western European Acheulean Project, this study aims to characterize Acheulean technology in Western Europe through the analysis of handaxes and cleavers from 10 key sites (Britain 4, France 4, and Spain 2) to acquire a regional view of the occupation. The historically different systems used to categorize and analyze the data have made it difficult to compare results. Here we apply a unified and simple method (Western European Acheulean Project) that combines the traditional technological and metrical analysis of assemblages containing handaxes and cleavers with an in-depth geometric morphometric approach using three-dimensional models.
View Article and Find Full Text PDFMuch of what is known about human behavior and subsistence strategies in the Levantine Middle Paleolithic comes from long sequences from caves and rock shelters. In this context, studies of stone tool function have traditionally focused on determining the use of Levallois points and triangular elements, either as projectiles or, more rarely, multipurpose knives. Little is known about such tool use and hafting in Middle Paleolithic open-air sites in the Levant through the systematic application of micro-wear analysis.
View Article and Find Full Text PDFLaser-induced damage growth has often been studied with Gaussian beams in the sub-picosecond regime. However, beams generated by high-power laser facilities do not feature Gaussian profiles, a property that raises questions concerning the reliability of off-line laser-induced damage measurements. Here, we compare laser-induced damage growth dynamics as a function of beam profiles.
View Article and Find Full Text PDFMore than 2 million years ago in East Africa, the earliest hominin stone tools evolved amidst changes in resource base, with pounding technology playing a key role in this adaptive process. Olduvai Gorge (now Oldupai) is a famed locality that remains paramount for the study of human evolution, also yielding some of the oldest battering tools in the world. However, direct evidence of the resources processed with these technologies is lacking entirely.
View Article and Find Full Text PDFArchaeological remains have highlighted the fact that the interglacial Marine Isotope Stage (MIS) 11 was a threshold from the perspective of hominin evolution in Europe. After the MIS 12 glaciation, considered one of the major climate-driven crises experienced by hominins, the archaeological records show an increasing number of occupations, evidence of new subsistence behaviors, and significant technical innovations. Here, we used statistical and geographic techniques to analyze the amphibian- and reptile-based paleoclimate and habitat reconstructions generated from a large data set of the Iberian Peninsula to (1) investigate if temperature, precipitation, and/or forest cover may have impacted the hominin occupation of the territory during the Early and Middle Pleistocene, (2) propose an 'Iberian' ecological model before and after the MIS 12/11 transition, and (3) evaluate, based on this model, the potential hominin occupation at a European scale.
View Article and Find Full Text PDFMetrology has been successfully used in the last decade to quantify use-wear on stone tools. Such techniques have been mostly applied to fine-grained rocks (chert), while studies on coarse-grained raw materials have been relatively infrequent. In this study, confocal microscopy was employed to investigate polished surfaces on a coarse-grained lithology, quartzite.
View Article and Find Full Text PDFBased on squared top-hat beam irradiations, we investigate how a change of the pulse duration in the picosecond regime affects the phenomenon of laser damage growth on dielectric mirrors. We first confirm two major previously reported experimental results with a Gaussian beam that are the existence of a growth threshold fluence smaller than the laser-induced damage threshold (LIDT) and the linear evolution, characterized by a growth coefficient, of the damage area with the number of irradiations when growth occurs. We then express the growth coefficient with the fluence and the growth threshold in particular.
View Article and Find Full Text PDFThe Atapuerca localities present evidence of a long series of hominin occupations from the Early Pleistocene onward and are a key site for understanding the continuity and discontinuity of Western European technological and settlement dynamics. The TD10 unit from Gran Dolina is located in the upper part of the sequence and divided into four lithostratigraphic subunits (TD10.4 to TD10.
View Article and Find Full Text PDFWe report on the implications that the temporal and spatial beam metrologies have on the accuracy of temporal scaling laws of Laser Induced Damage Threshold (LIDT) for dielectric materials in the picosecond regime. Thanks to a specific diagnostic able to measure the temporal pulse shape of subpicosecond and picosecond pulses, we highlight through simulations and experiments how the temporal shape has to be taken into account first in order to correctly understand the temporal dependency of dielectrics LIDT. This directly eases the interpretation of experimental temporal scaling laws of LIDT and improves their accuracy as a prediction means.
View Article and Find Full Text PDFThis paper aims to update the information available on the lithic assemblage from the entire sequence of TD6 now that the most recent excavations have been completed, and to explore possible changes in both occupational patterns and technological strategies evidenced in the unit. This is the first study to analyse the entire TD6 sequence, including subunits TD6.3 and TD6.
View Article and Find Full Text PDFThe Middle to Upper Paleolithic transition is often linked with a bio-cultural shift involving the dispersal of modern humans outside of Africa, the concomitant replacement of Neanderthals across Eurasia, and the emergence of new technological traditions. The Zagros Mountains region assumes importance in discussions concerning this period as its geographic location is central to all pertinent hominin migration areas, pointing to both east and west. As such, establishing a reliable chronology in the Zagros Mountains is crucial to our understanding of these biological and cultural developments.
View Article and Find Full Text PDFA technique that provides quantitative and spatially resolved retardance measurement is studied for application to laser-induced modification in transparent materials. The method is based on the measurement of optical path differences between two wavefronts carrying different polarizations, measured by a wavefront sensor placed in the image plane of a microscope. We have applied the technique to the investigation of stress distribution induced by CO laser processing of fused silica samples.
View Article and Find Full Text PDFZooarcheological research is an important tool in reconstructing subsistence, as well as for inferring relevant aspects regarding social behavior in the past. The organization of hunting parties, forms of predation (number and rate of animals slaughtered), and the technology used (tactics and tools) must be taken into account in the identification and classification of hunting methods in prehistory. The archeological recognition of communal hunting reflects an interest in evolutionary terms and their inherent implications for anticipatory capacities, social complexity, and the development of cognitive tools, such as articulated language.
View Article and Find Full Text PDFKaldar Cave is a key archaeological site that provides evidence of the Middle to Upper Palaeolithic transition in Iran. Excavations at the site in 2014-2015 led to the discovery of cultural remains generally associated with anatomically modern humans (AMHs) and evidence of a probable Neanderthal-made industry in the basal layers. Attempts have been made to establish a chronology for the site.
View Article and Find Full Text PDFResidue analysis is a method frequently used to infer the function of stone tools and it is very often applied in combination with use-wear analysis. Beyond its undeniable potential, the method itself has several intrinsic constraints. Apart from the exceptional circumstances necessary for residues to survive, the correct identification of the residue type is a very debatable topic.
View Article and Find Full Text PDFThis paper presents the lithic assemblages documented at Sima del Elefante (TE) and their importance in the context of the Early and Middle Pleistocene human occupation of Europe. We also study changes in human behaviour within the context of the palaeoenvironmental evolution of the Sierra de Atapuerca. This site has characteristics that are of great value for the study of human evolution.
View Article and Find Full Text PDFTwo archaeological assemblages from the Sierra de Atapuerca sites show evidence of anthropogenic cannibalism. These are the late Early Pleistocene level TD6-2 at Gran Dolina, and the Bronze Age level MIR4 in the Mirador Cave. Despite the chronological distance between these two assemblages, they share the common feature that the human remains exhibit a high frequency of anthropogenic modifications (cut marks, percussion pits and notches and peeling).
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