Vision for mobile robot localization in urban environments

This paper addresses the problem of mobile robot localization in urban environments. Typically, GPS is the preferred sensor for outdoor operation. However, using GPS-only localization methods leads to significant performance degradation in urban areas where tall nearby structures obstruct the clear view of the satellites. In our work, we use vision-based techniques to supplement GPS and odometry and provide accurate localization. The vision system identifies prominent linear features in the scene and matches them with a reduced model of nearby buildings, yielding improved pose estimation of the robot

BUILDING OWL ONTOLOGY IN FEDORA DIGITAL REPOSITORY

Digital repositories find more and more applications in various information systems and especially in e-learning systems. Along with storing digital objects the repositories need to also to represent domain knowledge, user profiles, multilanguage classification taxonomies, etc. This could be achieved by using ontologies represented in OWL. The Fedora digital repository is one of most powerful repositories. It supports relationships between the digital objects that are expressed in the RDF language. This allows implementation of OWL ontologies in Fedora. In this paper we describe in details our approach to represent OWL Lite ontologies in Fedora. We have also implemented a web based ontology editor that allows easy definition, modification and storing OWL ontologies in Fedora. The editor is written in PHP, uses the Fedora services for the interface with the repository and AJAX (jQuery) for building the user interface. The paper discusses also the architecture and the implementation of the editor

Tumor Necrosis Factor - alpha in Clinical Manifestation of Paroxysmal Atrial Fibrillation

Въведение: Предсърдното мъждене (ПМ) е най-честата аритмия в клиничната практика. Все повече данни се натрупват за участието на цитокините в патогенезата на аритмията, като обект на изследване до момента са преди персистиращата и перманентната форма на ритъмното нарушение.Цел: Да се потърсят промени в плазмените концентрации на TNF-α, свързани с изявата на пароксизмалното предсърдно мъждене (ППМ).Материал и методи: Плазмените концентрации на TNF-α бяха измерени трикратно при 51 пациенти (26 мъже и 25 жени; средна възраст 59.84 1.60 г) с ППМ, a именно: незабавно след хоспитализацията им (т.е. по време на ритъмното нарушение), 24 часа и 28 дни след възстановяване на синусов ритъм. Показателят беше измерен еднократно при 52 контроли (26 мъже и 26 жени; средна възраст 59.50 1.46 г.) без анамнестични или електрокардиографски данни за ПМ до момента. Плазмените концентрации на TNF-α бяха определени с ELISA кит (Elabscience Biotechnology Co., Ltd, China). Синусов ритъм бе възстановен медикаментозно с propafenone.Резултати: При постъпване на пациентите в отделението концентрациите на TNF-α бяха повишени спрямо тези на контролите (15.06 0.81 vs 8.20 0.29 pg/mL, p<0.001). Двадесет и четири часа след възстановяване на синусов ритъм промените персистираха (13.09 0.70 vs 8.20 0.29 pg/mL, p<0.001). На двадесет и осмия ден липсваше значима разлика (9.21 0.54 vs 8.20 0.29 pg/mL, p=0.10).Заключение: При ППМ се наблюдават динамични промени в плазмените концентрации на TNF-α. Те са значимо повишени по време на клиничната изява на ритъмното нарушение. След възстановяване на синусов ритъм те се нормализират бавно във времето. Специфичният характер на установените отклонения дават сериозно основание да се приеме клиничната им значимост за изявата на заболяването.Introduction: Atrial fibrillation is the most common arrhythmia in clinical practice. There has been a growing body of evidence in recent years of the role of inflammatory cytokines in the pathogenesis of the rhythm disorder, although the studies have been predominantly in the field of persistent and permanent atrial fibrillation. Aim: To find changes in plasma concentrations of TNF-α, concerning the clinical manifestation of paroxysmal atrial fibrillation. Materials and Methods: Plasma concentrations of IL-6 were measured three times in 51 patients (26 men and 25 women; mean age 59.84 1.60 yrs) with paroxysmal atrial fibrillation: once immediately after hospitalization of these patients (that is, during the rhythm disorder episode at baseline), then at 24 hours and finally 28 days after restoration of sinus rhythm. The plasma concentration was measured only once in the control group of 52 control subjects (26 men, 26 women; mean age 59.50 1.46 yrs). We used ELISA kit to determine the IL-6 concentrations. The sinus rhythm was restored with propafenone for all patients. Results: Baseline plasma concentrations of IL-6 were higher than those of controls (15.06.38 0.81 vs 8.20 0.29 pg/mL, p<0.001). The difference was retained for 24 hours after sinus rhythm restoration of (13.09 0.70 vs 8.20 0.29 pg/mL, p<0.001). At 28 days there was no statistically significant difference between patients and controls (9.21 0.54 vs 8.20 0.29 pg/mL, p=0.10). Conclusion: Dynamic changes of TNF-α plasma concentrations were established in paroxysmal atrial fibrillation. The cytokine levels were significantly elevated during the clinical manifestation of the arrhythmia. They decreased slowly after restoration of sinus rhythm. The changes we found provide a strong rationale to suggest that they are most likely relevant to the clinical manifestaton of paroxysmal atrial fibrillation

Visually-guided protein crystal manipulation using micromachined silicon tools

We present a system for protein crystal micro-manipulation with focus on automated crystal mounting for the purposes of X-ray data collection. The system features a set of newly designed micropositioner end-effectors we call microshovels which address some limitations of the traditional cryogenic loops. We have used micro-electrical mechanical system (MEMS) techniques to design and manufacture various shapes and quantities of microshovels. Visual feedback from a camera mounted on the microscope is used to control the micropositioner as it lowers a microshovel into the liquid containing the crystals and approaches a selected crystal for pickup. We present experimental results that illustrate the applicability of our approach

Visually-guided protein crystal manipulation using micromachined silicon tools

We present a system for protein crystal micro-manipulation with focus on automated crystal mounting for the purposes of X-ray data collection. The system features a set of newly designed micropositioner end-effectors we call microshovels which address some limitations of the traditional cryogenic loops. We have used micro-electrical mechanical system (MEMS) techniques to design and manufacture various shapes and quantities of microshovels. Visual feedback from a camera mounted on the microscope is used to control the micropositioner as it lowers a microshovel into the liquid containing the crystals and approaches a selected crystal for pickup. We present experimental results that illustrate the applicability of our approach

Dynamics of oxidative status in patients with paroxysmal atrial fibrillation

Introduction: Studies have established oxidative disorders in persistent and permanent atrial fibrillation. Our aim was to investigate oxidative status still in the early hours of paroxysmal atrial fibrillation (PAF) and monitor its changes after sinus rhythm (SR) restoration. Material and Methods: Levels of malondialdehyde and total glutathione were determined in plasma (Pl-MDA; Pl-GSH) and erythrocytes (Er-MDA; Er-GSH) together with erythrocyte glutathione peroxidase activity (GSH-Px) in 51 patients (59.84±1.6 years, 26 males). Markers were investigated upon hospital admission, 24 hours and 28 days after SR restoration. They were also determined in 52 healthy subjects (59.50±1.46 years, 26 males). Results: Mean AF duration prior to hospitalization was 8.14±0.76 hours. Upon admission, Pl-MDA and Er-MDA were significantly increased (p0.05). Conclusion: Disorder of oxidative status is detected in the early hours of PAF, which persists after SR restoration. Oxidative balance is restored slowly with time. This specific dynamics of oxidative status is most likely related to AF clinical course, namely to its manifestation and recurrences

Two-stage robotic crystal mounting of protein crystals for X-ray data collection

We present a new microrobotic system for a crystallographic task called protein crystal mounting, which is the transfer of a crystal from its growth solution onto a tool designed to hold it for X-ray data collection. The system operates autonomously using feedback from a camera looking at the workspace through a microscope. Visual tracking is employed to monitor the location of the selected crystal and control a range of actuators for successful extraction. The task is performed in two stages: First, the crystal is taken from its drop into a pipette and is transported into a cryoprotecting liquid. Second, while in the cryoprotector, it is transferred from the pipette onto a tool to be used for data collection. Key features of this approach are the increased robustness of the system and the avoidance of the damaging effect of direct exposure of the crystal to room conditions. This work is part of a larger effort we have directed at the automation of the high-throughput crystallographic pipeline

Design, architecture and control of a mobile site-modeling robot

A distributed, modular, heterogeneous architecture is presented that illustrates an approach to solving and integrating common tasks in mobile robotics, such as path planning, localization, sensor fusion, environmental modeling, and motion control. Experimental results are shown for an autonomous navigation task to confirm the applicability of our approach

Model methods for the manufacture of aesthetic restauration from lithium disilicate - case from the practice

В своето развитие денталната медицина и в частност зъботехниката от години се опитва да намери материал, който изцяло да наподобява структурата и здравината на естественото съзъбие. Въпреки непрестанните търсения и лутания в тази област използването на керамичните материали продължава да добива все по-голяма сила при опитите за доближаване до максималната естетика и твърдост на емай-ло-дентиновия комплекс при естествения зъб. Литиевият дисиликат е въведен като e.max и е достъпен във форми за пресоване или като блокче за изрязване чрез CAD-CAM система. Към този момент този материал изглежда идеален, защото вместо да отреже основата и да се наслоява с порцелан, материалът се проектира в анатомична форма и в цвят, което го прави изключително лесен за възстановявания в дистални участъци. Цялата корона представлява пресован литиев дисиликат, което я прави монолитна и монохромна, a за задни участъци здравината е приоритет пред естетиката. Във фронталните области бе създаден литиев диси ликат, преливащ от дентин към емайл - мултишейт, което подобри естетиката, a здравината остана непроменена около 400 МРа. В настоящия доклад е представена примерна методика на естетическо възстановяване с литиев дисиликат, илюстрирана със случай от практиката.In its development, dental medicine, and in particular the dental technician, has been trying for years to find a material that completely resembles the structure and strength of the natural dentition. Despite the constant research in this area, the use of ceramic materials continues to gain increasing power in attempts to approach the maximum aesthetics and rigidity of the enamel dentin complex in the natural tooth. Lithium disilicate has been introduced as e.max and is available in extrusion molds or as a cut-off block by a CAD-CAM system. For this model, this material looks ideal because, instead of cutting the base and lining it with porcelain, the material is designed in an an-atomical form and in a color that makes it extremely easy for restorations in distal areas. The whole crown is a pressed lithium disilicate which makes it monolithic and monochrome, and for the backs the strength is a priority for aesthetics. In the frontal areas, lithium disilicate was formed from dentin to enamel - a multicardite that improved aesthetics, and the strength remained unchanged at about 400 MPa