Introducing the Department of Anthropology

Článek představuje Ústav antropologie Přírodovědecké fakulty Masarykovy univerzity.The article presents the Department of Anthropology of the Faculty of Science, Masaryk University

Performance of distance-based matching algorithms in 3D facial identification

AbstractFacial image identification is an area of forensic sciences, where an expert provides an opinion on whether or not two or more images depict the same individual. The primary concern for facial image identification is that it must be based on sound scientific principles. The recent extensive development in 3D recording technology, which is presumed to enhance performances of identification tasks, has made essential to question conditions, under which 3D images can yield accurate and reliable results. The present paper explores the effect of mesh resolution, adequacy of selected measures of dissimilarity and number of variables employed to encode identity-specific facial features on a dataset of 528 3D face models sampled from the Fidentis 3D Face Database (N∼2100). In order to match 3D images two quantitative approaches were tested, the first based on closest point-to-point distances computed from registered surface models and the second grounded on Procrustes distances derived from discrete 3D facial points collected manually on textured 3D facial models. The results expressed in terms of rank-1 identification rates, ROC curves and likelihood ratios show that under optimized conditions the tested algorithms have the capacity to provide very accurate and reliable results. The performance of the tested algorithms is, however, highly dependent on mesh resolution and the number of variables employed in the task. The results also show that in addition to numerical measures of dissimilarity, various 3D visualization tools can be of assistance in the decision-making

Testing various imaging methods in assessment of hyoid bone fractures

In the field of forensic anthropology, the hyoid bone provides important evidence on victim’s biological profile (e.g., sex or age at death) and on potential foul play, because in addition to accidental (e.g., traffic accidents, medical-rescue interventions), and self-inflicted traumas (e.g., hanging), hyoid fractures have been vastly documented in assaulted injuries (e.g., manual or ligature strangulations). Still, an unbiased diagnosis of perimortem damage can be problematic as hyoid fractures frequently occur postmortem when a laryngeal region is being harvested and examined at autopsy. The aims of the present study was to explore characteristics of peri- and post-mortem fractures in hyoid bones by a variety of available examination techniques. The studied material consisted of selected fractured hyoid bones with documented demographic profiles and mechanisms of damage. Characteristics of the observed fractures (e.g., hyoid shape, fracture angle and surface characteristics of the fracture line) were assessed on a macroscopic level using traditional and advanced approaches (macro-photography, 3D laser scanning). Furthemore, micro-CT, RTG and SEM imaging methods were employed to examine damaged regions on a microscopic level. Special attention was given to the distinctions between peri- and post-mortem fractures by observing the cortical bone microstructure (as viewed on raw CT images, and generated 3D digital models) as the bone tissue properties are believed to reflect the mechanism of damage substantially. The acquired results provide an important insight into potentials and limitations of currently available imaging techniques employable in the course of assessing hyoid bone fractures in the framework of physical and forensic anthropology

Distal Part of the Human Hand: Study of Form Variability and Sexual Dimorphism Using Geometric Morphometrics

Tradičně se lidská ruka studuje prostřednictvím měření a srovnávání jednotlivých segmentů (prstů, článků prstů, záprstních kostí) bez zohlednění jejich vzájemných prostorových souvislostí. Cílem této studie je výzkum vnitro-populační variability formy lidské ruky jako celku v oblasti tříčlánkových prstů se zvláštním zaměřením na sexuální dimorfismus a vztah mezi velikostí a tvarem ruky. Pravé ruce 99 žen a 70 mužů, převážně vysokoškolských studentů, byly ve standardizované poloze z palmární strany zaznamenány běžným stolním skenerem. Na každém dvourozměrném snímku bylo umístěno 16 význačných bodů a byla studována variabilita mezi těmito konfiguracemi prostřednictvím metod geometrické morfometrie. Pro lepší pochopení vnitřních vzorců variability tvaru byl tvarový prostor rozložen na afinní a neafinní podprostor, které byly dále analyzovány samostatně. Převážná část celkové variability byla spojena s afinními tvarovými rozdíly, které jsou identické v celé studované oblasti ruky. Jejich větší část představovala střižnou změnu v proximodistálním směru, menší část pak napínání odpovídající změnám v šířce ruky. Toto napínání také silně korelovalo s velikostí ruky. Mezipohlavní rozdíly představovala afinní změna, ve které byla proximodistální střižná změna neoddělitelně spojena se změnami v relativní šířce ruky. Lokální neafinní pohlavní rozdíly byly zaznamenány v určitých článcích prstů a mohou souviset s rozdíly v poměrech délek prstů. Domníváme se, že oddělení globálních a lokálních sexuálně dimorfních znaků ruky může pomoci blíže ozřejmit původ/počátek jejich dimorfismu v rané ontogenezi – čím lokálnější znak, tím později se v ontogenezi zakládá. Dimorfní znaky lokální a globální by proto mohly být ovlivněny odlišnými ontogenetickými faktory.Traditionally, the human hand has been analyzed by measuring and comparing individual segments (fingers, phalanges, metacarpals) without considering their mutual spatial relationships. The present study aimed to analyze intra-population variability of the human hand form in the region of fingers as whole with special focus given to sexual dimorphism and the association between shape and size. Right hands of 99 females and 70 males, mostly college students, were scanned with a document scanner in standardized position from the palmar side. For each image 2-D coordinates of 16 landmarks were recorded and variability between configurations of landmarks were studied using geometric morphometrics. To understand patterns of variability, shape spaces were decomposed into affine and non-affine subspaces and further studied separately. The prevalence of the total variability was associated with affine shape change identical for the whole studied region of the hand. Its major portion was represented by shearing in proximodistal direction and to a lesser extent by straining in the relative hand width. The strain also strongly correlated with size of the hand. Intersexual differences were represented by affine change in which the proximodistal shearing was inextricably tied with the differences in relative hand width. Local non-affine sex differences were found in specific phalanges and might be associated with differences in finger length ratios. We presume that separating global and local sexually dimorphic features of the hand might shed light on the origin/onset of the dimorphism during early ontogeny – the more local the feature, the later differentiated, and thus influenced by different ontogenetic factors than global features

Age and Sex Differences in Mandibular Dental Arc Measurements in Subadults: Brno Collection of Orthodontic Dental Plaster Casts

Hodnocení mezipohlavních rozdílů v utváření dolní čelisti je jednou z mála možností, jak lze u nedospělých skeletů morfologicky odhadovat pohlaví. V této průřezové studii jsme se pokusili morfometricky prostudovat věkové rozdíly a ověřit existenci pohlavního dimorfismu ve velikosti a tvaru zubního oblouku dolní čelisti u nedospělých jedinců recentní české populace. Vzorek tvořilo 163 sádrových modelů dolních čelistí ortodontických pacientů, vybraných z Brněnské sbírky sádrových ortodontických modelů chrupu na základě stupně prořezání a nepřítomnosti zjevných patologií v rozsahu I(i)1-M1. Mladší kategorie od 7,5 let včetně do 9,5 let sestávala ze 77 případů (35 mužů a 42 žen), starší kategorie od 14 let včetně do 20 let z 86 případů (36 mužů a 50 žen). Velikost a tvar zubního oblouku jsme na standardizovaných fotografiích okluzní roviny hodnotili morfometricky pomocí jedenácti rozměrů, definovaných význačnými body na předních řezácích, špičácích a prvních trvalých stoličkách. Tvar jsme hodnotili pomocí šesti indexů. Ženy měly celkově menší rozměry zubního oblouku než muži stejné věkové kategorie, ve vyšší věkové kategorii byl velikostní dimorfismus mírně vyšší, ve většině rozměrů však nepřesahoval 5%. Rozdíly mezi věkovými kategoriemi nejsou jen odrazem prostého zvětšování čelisti v průběhu postnatálního růstu. Délka distální části zubního oblouku (C-M1) je ve vyšším věku u obou pohlaví menší. To může být způsobeno stěsnáváním mesiálnějších zubů s tím, jak se postupně prořezávají zuby distálnější. Ve většině hodnocených indexů se pohlaví výrazně nelišila, výjimkou byl Index vystupování špičáku v mladší věkové kategorii. Špičák vystupoval z oblouku bukálním směrem výrazněji ženám než mužům. Diskuse je věnována srovnání zjištěného dimorfismu s předchozími studiemi a možným vlivům, prostřednictvím kterých mohl klinický charakter sbírky a způsob výběru vzorku ovlivnit zjištěné mezipohlavní rozdíly.The evaluation of sex differences in mandibular development of subadult skeletons is one of only few possible methods of determining sex using morphological characteristics. In this cross-sectional study, we attempted to morphometrically investigate age differences and confirm the existence of sexual dimorphism using size and shape of the mandibular dental arch in subadults from a recent Czech population. The sample consisted of 163 plaster casts of mandibles from orthodontic patients in the Brno Collection of Orthodontic Dental Plaster Casts, selected on the basis of the degree of tooth eruption and the absence of visible pathological conditions in the I(i)1-M1 range. The younger age category ranging from 7,5 years to 9,5 years accounted for 77 cases (35 males and 42 females) and the older age category ranging from 14 to 20 years accounted for 86 cases (36 males and 50 females). The size and shape of the dental arch was evaluated using standardized photographs of the occlusal plane by employing eleven dimensions, with landmarks on central incisors, canines and first permanent molars. Shape was evaluated using six indices. The mean size of the dental arch was smaller in females than in males in the same age category. In the older age category the sexual dimorphism was slightly greater, but did not exceed 5% on most measurements. Differences between age categories are not simply a reflection of increasing size of the mandible with postnatal growth. The length of the distal segment of the dental arc (C(c)-M1 range) is shorter in the older category in both sexes. This could be caused by increased crowding of mesial teeth, with increasing eruption of distal teeth. Sex differences were not apparent on most shape indices, except for the Canine Protrusion Index in the younger age category. Canine protrusion from the arc in the buccal direction was greater in females than in males. The discussion is focused on comparison of the observed dimorphism with results found in previous studies and also possible ways in which the clinical character of the collection and method of sample selection could have affected the detected inter-sex differences

The assessment of the semicircular canals and cochlea of the human bony labyrinth using imaging techniques

The human bony labyrinth is an inner ear structure located inside the pyramid of the temporal bone that encloses the organs of sound perception and balance. As one of the most resistant skeletal elements in human body, the pyramid is frequently uncovered in a good state of preservation. Until recently, research of the human bony labyrinth had been restricted exclusively to irreversibly invasive techniques. Due to this invasiveness, literature on morphological variation has been scarce and many questions regarding population, age or sex-related differences are yet to be answered. The studied sample of pyramids originated from Dětkovice - Za zahradama Site (Czech Republic) dated to 1000’s and 1100’s A.D. All elements were examined using an X-ray Carestream Xtreme device and a cone-beam CT unit. In digital X-ray images, linear distance of the semicircular canals and cochlear diameter were measured in ImageJ program. CT images were first processed to generate 3D digital models, which were subsequently studied using a newly established PC-aided approach employing measuring functionalities available in GOM Inspect program. Altogether 39 variables were proposed in order to describe shape and size variation in the semicircular canals. Acquired measurements were confronted and tested against individual's demographic data determined based on corresponding skeletal elements and burial attributes. The results showed small to none sex-related and body side-specific differences. Still, statistically significant differences were shown between sub-adults and adults. They were particularly evident in size variables of the lumens of the lateral and posterior semicircular canal, where larger values for adults were provided. This indicates a widening of the canals during growth by the resorption in the vicinity of the canals. The acquired results contribute to our comprehension of the development of inner ear structures and demonstrate the potential of the employment of non-invasive approaches when examining human skeletal remains

Optically Stimulated Luminescence (OSL) Mortar Dating Inter-Comparison Study. The Second Round of Modis, Mortar Dating Inter-Comparison Study

Creative Commons Attribution NonCommercial-NoDerivatives licence 4.0[Abstract] After an intercomparison age experiment carried out in the framework of the first MODIS (MOrtar Dating Inter-comparison Study) project, the results showed general agreement both between optically stimulated luminescence (OSL) dating laboratories and with radiocarbon (14C) dating results. As the needs for the selection of samples convenient for an inter-comparison are not the same between 14C and OSL, for the second running, it has been decided to choose two different sample sets, one to share between the radiocarbon labs and one for the OSL dating ones. The results obtained by applying different experimental protocols (multigrain and single grain techniques) and different statistical models (weighted mean, central age mode, average dose model, minimum age model and exponential exposure dose) are discussed in this work

Importance of United Nations Security Council and binding effect of resolutions in maintenance of international peace and security

- Importance of United Nations Security Council and binding effect of resolutions in maintenance of international peace and security This paper depicts the history previous to creation and the creation itself of UN and the Security Council, followed by chapter devoted to the permanent and non- permanent members of the Council with subchapter about reform proposals in terms of its composition. Then there is detailed description of functions and powers of the Security Council, including also a topic relating to the Council's period of paralysis. In the chapter on voting procedure there is stressed the crucial issue of distinguishing procedural and non-procedural resolutions with talking about veto power as well. The final chapter is devoted to the decisions of the Security Council with focus on resolutions and their binding effect

Possibilities to increase the attraction of Bystřička municipality

Import 13/10/2008Prezenční118 - Katedra regionální a environmentální ekonomikyNeuveden