BIOMECHANICAL MODELS AND MEASURING TECHNIQUES FOR ULTRASOUND-BASED MEASURING SYSTEM DURING GAIT

Nowadays clinical motion analysis is a usual method. More and more laboratories offer their facilities and use this investigation for supporting doctors in their decisions. During the past two years a new and modern on-line motion analysis system was established at the Department of Applied Mechanics which is capable for a complex analysis of the upper limb, the gait, the run, other cyclic movements, and the spine. This paper focuses on the presentation of a new 3D motion analysis technique for treadmill walking. An ultrasound-based 3D measurement system and a measuring arrangement developed were used to measure and determine gait parameters during treadmill walking. The model considers each limb segment to be a rigid body, linked to each other by a joint. This paper also presents a new 3D motion analysis software package for treadmill walking and introduce the DataManager developed. We studied knee kinematics and temporal-distance gait measurement parameters (step length, stride length, stride width, etc.) to be obtained from treadmill walking. Treadmill walking allows the analysis of several cycles of each subject. On the basis of the analysis the standard deviation of temporal-gait parameters and the knee kinematics data of each subject can be established. The 3D movement analysis system presented is a suitable and standardized procedure for quick gait analysis

A SPECIAL MOTION AND PERFORMANCE ANALYSIS OF PROFESSIONAL CYCLIST

The biomechanical analysis of sport-motion is a new joint research field of biomechanics and sport medicine. Each cyclist was examined at an own bike mounted on an ergometer for analyzing the motion and the muscle activity at different loading. The ultrasoundbased 3D motion analysis- system and surface EMG signals were used to measure the motion parameters during the cycling. The kinematical parameters, such as the knee angle, and the muscle activity of four muscle groups were determined in every cycle of pedaling. The lactic-acid amount of the capillary-blood and the pulse were checked during the exercise. On the basis of the analysis, it can be established that the movement and the muscle activity are disordered close to the anaerobic threshold; thereafter, they become ordered. The results o the examination give effective help to trainers and athletes to improve the performance

Graph construction with condition-based weights for spectral clustering of hierarchical datasets

Most of the unsupervised machine learning algorithms focus on clustering the data based on similarity metrics, while ignoring other attributes, or perhaps other type of connections between the data points. In case of hierarchical datasets, groups of points (point-sets) can be defined according to the hierarchy system. Our goal was to develop such spectral clustering approach that preserves the structure of the dataset throughout the clustering procedure. The main contribution of this paper is a set of conditions for weighted graph construction used in spectral clustering. Following the requirements – given by the set of conditions – ensures that the hierarchical formation of the dataset remains unchanged, and therefore the clustering of data points imply the clustering of point-sets as well. The proposed spectral clustering algorithm was tested on three datasets, the results were compared to baseline methods and it can be concluded the algorithm with the proposed conditions always preserves the hierarchy structure

Endoprotézis beültetés hatásának biomechanikai elemzése in-vivo mozgáselemzéssel = Biomechanical analysis of effect of endoprothesis with in vivo motion analysis

I. Megteremtettük a komplex biomechanikai mozgáselemzés rendszert, amely alkalmas a járás, a hirtelen irányváltoztatásra történő reagálás, a vállízület mozgásainak elemzésére, valamint a protézisek kilazulásának mérésére. II. Az idős egészséges személyek adatbankja több járássebesség esetén tartalmazza a távolság-idő, szögjellegű és alakváltozás-jellegű paramétereket, valamint azok változékonyságát leíró relatív szórásokat, továbbá a kinesztézist jellemző paramétereket. III. Elvégeztük a csípőízületi arthrosissal rendelkező, protézis beültetésen átesett betegek komplex mozgásvizsgálatát, az eredményeket összehasonlítottunk az egészséges kontrollcsoport eredményeivel. Megállapítottuk, hogy az antero-laterális feltárási móddal az egészséges mozgáskép hamarabb elérhető. IV. Elvégeztük a térdízületi arthrosissal rendelkező, a protézis beültetésen átesett betegek komplex mozgásvizsgálatát, az eredményeket összehasonlítottunk az egészséges kontrollcsoport eredményeivel. Megállapítottuk, hogy a minimal-invazív feltárási móddal az egészséges mozgáskép hamarabb elérhető. V. Elvégeztük a multidirekcionális vállízületi instabilitással rendelkező betegek mozgásvizsgálatát műtét/konzervatív kezelés előtt, melyeket összehasonlítottunk az egészségesek eredményeivel. Az egészséges vállízületi mozgás csak műtéti úton rekonstruálható. A vállízületi arthrosis szignifikánsan megváltoztatja a mozgásképet, a két típusú protézis biomechanikai hatása szignifikánsan eltérő. | I. A complex biomechanical motion analysis system was created, which is suitable for the modeling of gait, stepping, provocation, for analyzing shoulder motion and for measuring endoprothesis migration. II. The data bank of elderly, healthy subjects includes spatio-temporal, angular and deflection parameters and their coefficients of variance at different gait speeds, as well as the parameters modeling kinesthesis. III. The complex motion analysis of patients with hip osteoarthrithis was executed before and after total hip reconstruction, and compared with the data of the control group. The gait of patients operated by the antero-lateral inclusion method became similar to the gait of healthy subjects earlier. IV. The complex motion analysis of patients with knee osteoarthrithis was executed before and after total knee reconstruction, and compared with the data of the control group. The gait of patients operated by the minimal invasive inclusion method became similar to the gait of healthy subjects earlier. V. The motion analysis of patients with multidirectional shoulder instability was executed before conservative / surgical treatment and compared to the data of controls. Healthy motion could be restored only by surgery. Shoulder arthrosis significantly influenced shoulder motion, and the biomechanical effects of the two different types of endoprosthesis significantly differ from each other

A longevity study with enhancer substances (selegiline, BPAP) detected an unknown tumor-manifestation-suppressing regulation in rat brain

AIMS: First proof to show that (-)-deprenyl/selegiline (DEP), the first selective inhibitor of MAO-B, later identified as the first beta-phenylethylamine (PEA)-derived synthetic catecholaminergic activity enhancer (CAE) substance and (2R)-1-(1-benzofuran-2-yl)-N-propylpentane-2-amine (BPAP), the tryptamine-derived presently known most potent, selective, synthetic enhancer substance, are specific markers of unknown enhancer-sensitive brain regulations. MAIN METHODS: Longevity study disclosing the operation of tumor-manifestation-suppressing (TMS) regulation in rat brain. Immonohistochemical identification of a fibromyxosarcoma in rats. Experiments with human medulloblastoma cell lines. Analysis of the mechanism of action of enhancer substances. KEY FINDINGS: Whereas 20/40 saline-treated rats manifested a fibromyxosarcoma, in groups of rats treated with 0.001mg/kg DEP: 15/40 rats; with 0.1mg/kg DEP: 11/40 rats (P<0.01); with 0.0001mg/kg BPAP: 8/40 rats (P<0.001); with 0.05mg/kg BPAP: 7/40 rats (P<0.01) manifested the tumor. Experiments with human medulloblastoma cell lines, HTB-186 (Daoy); UW-228-2, showed that BPAP was devoid of direct cytotoxic effect on tumor cells, and did not alter the direct cytotoxic effectiveness of temozolomide, cisplatin, etoposide, or vincristine. Interaction with distinct sites on vesicular monoamine-transporter-2 (VMAT2) is the main mechanism of action of the enhancer substances which clarifies the highly characteristic bi-modal, bell-shaped concentration-effect curves of DEP and BPAP. SIGNIFICANCE: Considering of the safeness of the enhancer substances and the finding that DEP and BPAP, specific markers of unknown enhancer sensitive brain regulations, detected the operation of an enhancer-sensitive TMS-regulation in rat brain, it seems reasonable to test in humans low dose DEP or BPAP treatment against the spreading of a malignant tumor