Scanning method for indoor localization using the RSSI approach

This paper presents a scanning method for indoor mobile robot localization using the received signal strength indicator (RSSI) approach. The method eliminates the main drawback of the conventional fingerprint, whose database construction is time-consuming and which needs to be rebuilt every time a change in indoor environment occurs. It directly compares the column vectors of a kernel matrix and signal strength vector using the Euclidean distance as a metric. The highest resolution available in localization using a fingerprint is restricted by a resolution of a set of measurements performed prior to localization. In contrast, resolution using the scanning method can be easily changed using a denser grid of potential sources. Although slightly slower than the trilateration method, the scanning method outperforms it in terms of accuracy, and yields a reconstruction error of only 0. 08 m averaged over 1600 considered source points in a room with dimensions 9.7 m × 4.7 m × 3 m. Its localization time of 0. 39 s makes this method suitable for real-time localization and tracking

Optimal Magnetic Sensor Vests for Cardiac Source Imaging

Magnetocardiography (MCG) non-invasively provides functional information about the heart. New room-temperature magnetic field sensors, specifically magnetoresistive and optically pumped magnetometers, have reached sensitivities in the ultra-low range of cardiac fields while allowing for free placement around the human torso. Our aim is to optimize positions and orientations of such magnetic sensors in a vest-like arrangement for robust reconstruction of the electric current distributions in the heart. We optimized a set of 32 sensors on the surface of a torso model with respect to a 13-dipole cardiac source model under noise-free conditions. The reconstruction robustness was estimated by the condition of the lead field matrix. Optimization improved the condition of the lead field matrix by approximately two orders of magnitude compared to a regular array at the front of the torso. Optimized setups exhibited distributions of sensors over the whole torso with denser sampling above the heart at the front and back of the torso. Sensors close to the heart were arranged predominantly tangential to the body surface. The optimized sensor setup could facilitate the definition of a standard for sensor placement in MCG and the development of a wearable MCG vest for clinical diagnostics

Nekropola Slog – Timacum Minus u Ravni kod Knjaževca. Zaštitna arheološka iskopavanja u 2013. godini

Rimsko utvrđenje Timacum Minus nalazi se na oko 8km severno od Knjaževca i 800m severoistočno od sela Ravna na levoj obali Belog Timoka. Arheološka istraživanja ovog nalazišta započeo je 1975 . godine Arheološki institut i Beograda koji u saradnji sa Zavičajnim muzejom Knjaževca realizuje ovaj projekat već skoro četiri decenije

Indoor localization: novel RSSI approach based on analytical solution and two receivers

Indoor localization based on trilateration method uses at least three receivers for an accurate localization in 2-D. We performed indoor localization in 2-D using only two receivers, combining algebraic equations for signal strengths into one quadratic equation with transmitter position as unknown and using a specific receiver placement at the two adjacent corners of the room. This receiver arrangement assures unique coordinates of the transmitter position inside a room, rejecting automatically the other solution which appears outside the room volume. The accuracy of the method is numerically tested in a room with dimensions of 9.7 m × 4.7 m × 3 m and shows a mean reconstruction error of 3.4 cm

DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells

We investigated the genotoxic responses to two types of TiO2 nanoparticles (<25 nm anatase: TiO2-An, and <100 nm rutile: TiO2-Ru) in human hepatoma HepG2 cells. Under the applied exposure conditions the particles were agglomerated or aggregated with the size of agglomerates and aggregates in the micrometer range, and were not cytotoxic. TiO2-An, but not TiO2-Ru, caused a persistent increase in DNA strand breaks (comet assay) and oxidized purines (Fpg-comet). TiO2-An was a stronger inducer of intracellular reactive oxygen species (ROS) than TiO2-Ru. Both types of TiO2 nanoparticles transiently upregulated mRNA expression of p53 and its downstream regulated DNA damage responsive genes (mdm2, gadd45α, p21), providing additional evidence that TiO2 nanoparticles are genotoxic. The observed differences in responses of HepG2 cells to exposure to anatase and rutile TiO2 nanoparticles support the evidence that the toxic potential of TiO2 nanoparticles varies not only with particle size but also with crystalline structure

Arheološka istraživanja, prezentacija I promocija rimskog utvrđenja I naselja Timacum Minus u 2020. godini

U okviru projekta Arheološkog instituta u Beogradu i Zavičajnog muzeja Knjaževac Arheološka istraživanja, prezentacija i promocija rimskog utvrđenja i naselja Timacum Minus u Ravni kod Knjaževca, u periodu od 26. 08. do 24. 09. 2020. godine izvršena su iskopavanja na sektoru južne kapije i na prostoru velike građevine u središtu utvrđenja (principia

Nekropola Slog – Timacum Minus, zaštitna iskopavanja 2015. godine

Na prostoru južno od idanih groni a i istočno od sonde 1 u njeno produžetku od istočnog proila AB postavljena je sonda prava sever jug di en ija 5 onače na kao sonda 15 l. 1. ovogodišnjoj ka panji istraživanja og vre en skog ograničenja uslov ljenog skro ni inansij ski sredstvi a prvo su istraženi gro ovi konsta tovani na kraju prošlogo dišnje ka panje G.1 u sondi 21 i G.1 u sondi 1 l. 2 i novootkrive ni gro ovi G.1 u o ru šeno apadno proilu sonde 11 i G.10 u son di 1 ispod gro a 1 . središnje delu sonde 15 otkrivena su još tri gro a G.1 11 tako da je 2015. godine istraženo ukupno seda gro ova. akođe utvrđeno je da je severni deo sonde 15 oštećen ero ijo južnog proila arheološkog iskopa i 1 1 5. godine dok je južni deo sonde deva stiran neki reentni ukopo koji se pruža u pravu istok apad najve rovatnije vojni rovo i prvih deenija 20. veka i Balkanskih ratova i ili rvog svetskog rata sudeći po nala i a gvodenog dug eta sa vojničkog undira i gvodenog kuhinjskog noža. sondi 15 konstatovana je identična stratigraija kulturnih slojeva kao u prethodni ka panja a etković et al 201 etković et al. u štampi

Analysis of loss of heterozygosity of the tumor suppressor genes p53 and BRCA1 in ovarial carcinomas

Background/aim: Among the genes involved in ovarian carcinogenesis, there has been increased interest in tumor-suppressor genes p53 and BRCA1. Both of the genes make control of cell cycle, DNA repair and apoptosis. The p53 is a "genome guardian" inactivated in more than 50% of human cancers, while BRCA1 mutations are found mostly in breast and ovarian cancer. The aim of this investigation was to establish the frequency of loss of heterozygosity (LOH) in the regions of the genes p53 and BRCA1 in ovarian carcinomas, and to analyze the association of LOH with the disease stage and prognosis. Methods. We analyzed 20 patients with a confirmed diagnosis of epithelilal ovarian carcinoma. DNA for molecular-genetic analysis was extracted from the tumor tissue and blood as normal tissue of each person. Microsatellite markers of the regions of genes p53 and BRCA1 were amplified by PCR method. The determination of allelic status of microsatellites and detection of LOH was performed after PAA gel electroforesis. Results. Both of the analyzed microsatellite markers were informative in 13/20 (65%) cases. In the region of gene p53, LOH was established in 4/13 (30.7%) tumors. One of them had histological gradus G1, one had gradus G2, and two of them had gradus G3, while all were with the International Federation of Gynecology and Obstetrics (FIGO) IIIc stage. In the region of gene BRCA1, LOH was detected in 5/13 (38.5%) tumors. Four of them had histological gradus G2, and one had gradus G3, while by the (FIGO) classification one was with stage Ib, one was with stage IIIb, while the three were with stage IIIc. LOH in both of the analyzed regions was detected in one tumor (7.7%), with histological gradus G3 and the FIGO IIIc stage. Conclusion. The frequency of LOH in epthelial ovarian carcinomas was 30.7% and 38.5% for p53 and BRCA1 gene regions, respectively. Most of tumors with LOH had histological gradus G2 or G3, and the clinical FIGO stage IIIc, suggesting the association of this occurrence with a later phase of the disease