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Abstract

In recent years, Global Navigation Satellite Systems (GNSS) have gained great importance in terms of the benefits it provides such as precise geodetic point positioning, determining crustal deformations, navigation, vehicle monitoring systems and meteorological applications etc. As in Turkey, for this purpose, each country has set up its own GNSS station networks like Turkish National Permanent RTK Network analyzed precise station coordinates and velocities together with the International GNSS Service , Turkish National Fundamental GPS Network and Turkish National Permanent GNSS Network (TNPGN) stations not only are utilized as precise positioning but also GNSS meteorology studies so total number of stations are increased. This work is related to the reactivated of the TRAB IGS station which was established in Karadeniz Technical University, Department of Geomatics Engineering. Within the COST ES1206 Action (GNSS4SWEC) KTU analysis center was established and Trop-NET system developed by Geodetic Observatory Pecny (GOP, RIGTC) in order to troposphere monitoring. The project titled “Using Regional GNSS Networks to Strengthen Severe Weather Prediction” was accepted to the scientific and technological research council of Turkey (TUBITAK). With this project, we will design 2 new constructed GNSS reference station network. Using observation data of network, we will compare water vapor distribution derived by GNSS Meteorology and GNSS Tomography. At this time, KTU AC was accepted as E-GVAP Analysis Centre in December 2016. KTU reference station is aimed to be a member of the EUREF network with these studies.
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Authors and Affiliations

Selma Zengin Kazancı
Emine Tanır Kayıkçı
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Abstract

Unmanned aerial vehicles are increasingly being used in close range photogrammetry. Real-time observation of the Earth’s surface and the photogrammetric images obtained are used as material for surveying and environmental inventory. The following study was conducted on a small area (approximately 1 ha). In such cases, the classical method of topographic mapping is not accurate enough. The geodetic method of topographic surveying, on the other hand, is an overly precise measurement technique for the purpose of inventorying the natural environment components. The author of the following study has proposed using the unmanned aerial vehicle technology and tying in the obtained images to the control point network established with the aid of GNSS technology. Georeferencing the acquired images and using them to create a photogrammetric model of the studied area enabled the researcher to perform calculations, which yielded a total root mean square error below 9 cm. The performed comparison of the real lengths of the vectors connecting the control points and their lengths calculated on the basis of the photogrammetric model made it possible to fully confirm the RMSE calculated and prove the usefulness of the UAV technology in observing terrain components for the purpose of environmental inventory. Such environmental components include, among others, elements of road infrastructure, green areas, but also changes in the location of moving pedestrians and vehicles, as well as other changes in the natural environment that are not registered on classical base maps or topographic maps.
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Authors and Affiliations

Maciej Smaczyński
Beata Medyńska-Gulij
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Abstract

Introduction: Graves’ Disease (GD) is an autoimmune hyperthyroidism occurring mostly in young women. The main pathogenic role of the disease is attributed to TSH receptor antibodies (TRAb), which stimulate the thyroid gland to increase production of the most active thyroid hormone- triiodothyronine (T3). High level of TRAb and a large goiter size are commonly known as poor prognostic factors for the disease and are used to predict relapse.

The aim: The purpose of our study was to check the correlation between fT3:fT4 ratio with TRAb concentration, total volume of thyroid and age of GD onset.

Materials and Methods: 114 patients with onset or relapse of GD were analyzed. Those after thyroidectomy or radioiodine therapy were not taken into analysis. The data was retrospectively retrieved from the hospital’s records consisting of patients’ sex, age, level of TRAb, fT3, fT4 and thyroid volume on ultrasonography. The association between fT3:fT4 and TRAb concentration, thyroid volume and age was evaluated using Pearson correlation coefficient.

Results: The group was predominated by women (19.3% men, 80.7% women). The average age was 47.0. The analysis revealed positive correlation between: 1) fT3:fT4 ratio and total volume of thyroid (correla-tion ratio: 0.37; p <0.05) 2) fT3:fT4 ratio and level of TRAb (correlation ratio: 0.26; p <0.05) 3) negative correlation between fT3:fT4 ratio and patient’s age (correlation ratio: –0.14; p = 0.144.

Conclusions: Positive correlations between fT3:fT4 ratio and TRAb level and total volume of thyroid (poor predictors of GD) may confirm that high level of fT3 can also be a prognostic factor for GD severity.

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Authors and Affiliations

Mari Minasyan
Aleksandra Dulęba
Anna Smalarz
Maria Stręk
Paweł Bryniarski
Elwira Przybylik-Mazurek
Alicja Hubalewska-Dydejczyk

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