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Proposed paper presents application of the patch test for meshless analysis of piezoelectric circular plate with functionally graded material properties. Functionally graded materials (FGM) are the special class of composite materials with continuous variation of volume fraction of constituents in predominant direction. Patch test analysis is an important tool in numerical methods for addressing the convergence. Meshless local Petrov-Galerkin (MLPG) method together with moving least-squares (MLS) approximation scheme is applied in the analysis. No finite elements are required for approximation or integration of unknown quantities. Circular plate is considered as a 3-D axisymmetric piezoelectric solid. Considering the axial symmetry, the problem is reduced to a 2-dimensinal one. Displacement and electric potential fields are prescribed on the outer boundaries in order to reach the state of constant stress field inside the considered plate as required by the patch test and the governing equations. Values of prescribed mechanical and electrical fields must be determined in order to comply with applied FGM gradation rule. Convergence study is performed to assess the considered meshless approach and several conclusions are finally presented.

The main purpose of this paper is to describe the mechanism of the effect of high load on bone tissue and its ability to adapt to the given load. In the first part of this paper I am going to focus on the description of the mechanism of the load effect on bone tissue according to the mechanostat theory of Harold Frost and Jullius Wolff. In the second part I am going to describe how high load affects the bone tissue and how the adaptation mechanisms of the bone will react to the load. In this part I am also going to focus on pathological high load and the occurrence of cracks and fractures on bones due to this load being higher than the bone can sustain. In the last part of the paper I am going to focus on the bone repair mechanisms needed when fractures and cracks disrupt the integrity of the bone. Keywords Adaptability of the bone, physiological mechanisms of the bone, pathological overload, Frost's mechanostat, reparational mechanisms of the bone, bone damage

In this thesis, the energy consumption during manual wheat grinding was investigated using two historically widespread and important technologies for grain grinding, namely the saddle quern and the rotary quern. This energy consumption was also compared to some anthropometric parameters of the grinding human. The method of indirect calorimetry using Cosmed K5 was used to measure energy expenditure. Bioimpedance scale InBody270 and basic anthropometric tools such as anthropometer and pelvimeter were used to determine selected body parameters.. The energy expenditure of grinding by the rotary quern was also measured by different movement patterns, namely unimanual clockwise and counter-clockwise rotation and bimanual counter-clockwise rotation. Energy expenditure was sampled on 30 women. It was found that although grinding on a saddle quern is an energetically less demanding activity compared to grinding on a rotary quern, significantly more energy is required to grind the same amount of cereal grains (297 kcal/kg grain vs. 109 kcal/kg grain). Clockwise milling was found to be the most energy-efficient variant of milling, while counter-clockwise milling was more energy demanding (clockwise milling 5.48  1.13 kcal/min vs. counter-clockwise milling 6.21  0.87 kcal/min). Anthropometric parameters...

Body mass is one of the basic human characteristics used in various anthropological disciplines and can be used in behavioral and environmental studies of present and past populations. This thesis provides a brief summary of methods by which the body mass can be retrospectively reconstructed from skeletal dimensions in juvenile individuals. It also summarizes the important factors which may affect the weight reconstruction, as the child skeleton is more sensitive to environmental influences than the adult skeleton. The effects of nutrition, genetics, physical activity and ecogeography are discussed. Key words: body mass estimation, body mass, ontogeny, growth, postcranial skeleton

Past studies concerning deriving periosteal and endosteal contours from micro-CT scans of non-adult long bones found the greatest error to stem from the automatic processing of the endosteal contours. Furthermore, with increasing age, a decrease in the estimation error of the cross-sectional properties was observed. This study aims to identify the specific source of the estimation error and to optimize the use of the automatic method of deriving endosteal contours. Four parameters (circularity, solidity, roundness, and aspect ratio) were used to quantify the shape properties of the endosteal contour. These parameters were tested on 91 individuals from birth to early adulthood. As for the ontogenic changes in the endosteal contour, a continuous decrease in the jaggedness of the endosteal contour had been observed, mainly based on the changes in the circularity. Circularity was chosen as the parameter upon which the criteria of use of the automatic method of deriving the endosteal contour was based. The criterium is based on the prediction of whether the customary threshold of 5 % percent prediction error would be surpassed while using the automatic method at a certain level of circularity. Applying the criteria of the minimum threshold of circularity (0,83 for MA, 0,71 for CA, and 0,7 for ZP) will...

Measures of bone robusticity are used in order to reconstruct habitual activity of past populations. The aim of this bachelor thesis is to summarize the development of bone biomechanical properties and to create an overview of the factors affecting the ontogeny of human bone robusticity. The covered influences include genetics, ecogeographical environment and subsistence strategies. An emphasis is put on the mechanical load as it is considered a key determinant of postcranial robusticity. Additionally, the interplay of these factors and its influence on the adult robusticity is discussed. Key words: bone functional adaptation, habitual activity, ontogeny, robusticity, strain

Changes in the external surfaces on the lower limb bones can be caused by various taphonomic factors. It is important for our work how these changes will affects. The aim of the work was to process and subsequently evaluate the changes in the external surfaces on the lower limb bones. For analyses we chose set of adults from 2nd church burial ground Pohansko near Břeclav, we chose specifically braid of the lower limbs (cingulum membri inferioris) and free lower limb (pars libera membri inferioris). We wrote down taphonomic changes into prepared protocols, changes were typologically about damages and color changes. We used programs InkScape and AdobePhotoshop to transform paper protocols into digital form. Heat maps are outputs from this programms through them we are able to see incidence rate of individual changes. We most often detected the occurrence of an orange color on the bones of the lower limbs, so we focused on its cause. We found an increased content of silicon and aluminum in its chemical composition, so we assume that it could be an aluminosilicate weathering product. Key words: Pohansko, taphonomy, taphonomic factors, bone surface, lower limb

This theses explores muscle activity during bow draw. The goal of his study is to evaluate whether muscle activity corresponds with increase in mechanical robusticity of the left humerus found in mezolithic osteological material. Muscle activity is measured by the means of surface electromyography. We measure activity of arm and back muscles. Activity was measured on m. deltoideus, m. infraspinatus, m. biceps brachii, m. triceps brachii and m. latissimus dorsi. Muscle activity was measured on 20 male archers, during bow draw of three wooden long-bows. Results of this study support the idea that change in robusticity of the left humerus could be caused by frequent bow use in post-glacial Europe.

The preservation of the bones and their appearance depends on the conditions in which the individual was buried. The aim of the diploma thesis was to explore protocols, quantify periosteal changes and try to interpret them. For quantification, we chose the upper limb - the cingulum membri superioris and pars libera membri superioris without the skeleton of the hand (ossa manus). We examined skeletal remains of 55 individuals (25 women, 30 men) from the burial site at the 2nd church in Pohansko. The burial site dates back to the Great Moravia period (the end of the 9th and beginning of the 10th century). We recorded periosteal changes in images that we digitized in InkScape. In InkScape, we localized periosteal changes, and using ImageCalculator, we found the area of percentage of periosteal changes on the bone surface. We observed two types of periosteal changes: bone damage (for example absence of periosteal surface, exposed spongiosis) and color changes (for example orange, black or green discoloration). By digitizing protocols and processing them in InkScape, we analyzed the areas of occurrence for individual periosteal changes and, using ImageCalculator, we found the most common area of periosteal changes. The most frequent bone damage was the absence of the periosteal surface and the most...

Skeletal remains of anatomically modern humans could be a source of informations about movement activities carried out during life. Archery was an important activity for our ancestors and it is an activity that can leave a trace on the skeleton. So far, no research asked the question whether traces left on skeletal remnants correspond to some general pattern related to archery. Enthesopathies and long bone shafts are the subject of this thesis because these methods are used in the reconstruction of archery. Reviewed literature suggests that long bone shafts are useful in the activity reconstruction. Enthesopathies are useful as well but it is important to consider some specific properties of enthesopaties when using them. Information gained from the enthesopathies and long bone shafts should be explained in a historical context. For this reason, this thesis provides context by adding a general chapter related to bow in general and to hunting activities with a bow. Reviewed literature suggests that it is indeed possible to find a general pattern of a skeletal traces for archery with long bone shafts but probably not with enthesopathies.