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The main objective of this study was to investigate the correlation between the indoor and outdoor ambient dose equivalent rates measured by the ion chamber inside and around the historical sacral objects at a few locations in Bosnia and Herzegovina. The investigated objects made of the traditional building materials were built in the Late Medieval, Post Medieval, and Ottoman Period of Bosnia and Herzegovina history. The LUDLUM Model 9DP instrument based on a pressurized ion chamber was selected for natural low level radiation measurements since the ionisation chambers have higher sensitivities than the other types of detectors. The detection capability of the LUDLUM Model 9DP pressurized ion chamber was examined in the laboratory conditions with a source of low activity and under natural environmental radiation conditions by measuring the indoor and outdoor dose rates. A weak positive correlation was found between the ambient dose equivalent rates inside the historical sacral objects and the dose rates outside the objects. The average evaluated value of the indoor to outdoor dose rate ratio of 1.07 for the studied historic objects is less than that obtained for the contemporary building materials such as concrete. No study on the indoor to outdoor dose rate ratio in Bosnia and Herzegovina measured by the LUDLUM 9DP dose rate meter based on an ion chamber has been conducted yet. In addition to direct measurements, the first gamma spectrometric analysis of a few samples of building materials from the Late Medieval period in Bosna and Herzegovina was performed. The results of the gamma analysis revealed almost uniform distribution of primordial radionuclides in the investigated samples. It was demonstrated that such materials had the reduced content of radioactive isotopes compared to the contemporary building materials and therefore they could have potential advantages in specific applications related to the environmentally sustainable architecture.

The personal dosimetry in Bosnia and Herzegovina started in 1960. After a brief interruption in 1990s, the dosimetry service resumed in 1999. Until 2013, the Radiation Protection Centre of the Institute of Public Health of Federation of Bosnia and Herzegovina has been the only institution in the country that could provide this service. In 2013, this Center covered more than 70 % (1,485) of all radiation workers in the country. They mostly worked in medical institutions (1,417 or 95.4 %), while others are exposed to radiation sources in industry and veterinary radiology. From 1999 to 2013, the majority of annual doses were less than 1 mSv (96.2 %). There are no registered cases of exceeding the annual dose limit (20 mSv). The results analysis shows the reduction of individual doses in last five years. Newly adopted practices in medicine, such as the positron emission tomography, could cause the increase of doses in the years to come.

Introduction: The introduction of hybrid imaging systems such as Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) has completely changed the scanning procedure of conventional diagnostic nuclear medicine protocols. Modern bone scintigraphy protocols include SUV quanitification and Whole Body (WB) SPECT/CT scanning modality. The major limitation of these new technologies is relatively long scanning time. New detector systems with modern reconstruction softwares have been developed for fast scanning SPECT protocolos. These new technologies can produce images of reduced acquisition with same quality as full scanning acquisition. As a result new studies suggest that planar WB scintigraphy should be replaced with WB SPECT/CT. Methods: One hundred oncology patients performed SPECT/CT as a part as their clinical follow-up. Three different scanning and three reconstruction protocols have been evaluated. Two nuclear medicine physicians evaluated with Likert scale image sharpness, lesion visibility, and lesion background detectability. The overall image quality was determined as the sum of these three parameters. Results: In terms of scan duration reduction on image quality, Volumetrix Evolution for Bone performed during ultra-fast SPECT acquisition achieved the highest score, which is superior compared to the standard SPECT acquisition protocol. The overall image quality was the best with the Volumetrix MI Evolution for Bone protocol for ultra-fast acquisition Conclusion: The Evolution for Bone protocol for ultra-fast acquisition showed best results compared to other protocols. The adoption of new acquisition SPECT protocol may offer more comfortable exams, resulting in higher patient satisfaction. The implementation of this new protocol can lead to an improvement in SPECT sensitivity, primarily due to the reduction of SPECT motion artifacts.

Introduction: Computed tomography angiography (CTA) represents the gold standard as a method for the diagnosis of carotid artery diseases. The current topic is the use of CTA for the evaluation of carotid arteries with a reduction in the dose of contrast agent and dose of ionizing radiation, which, with adequate preparation, would enable the use of this method in some risk groups. The aim of this study was to evaluate the feasibility and image quality of a new low-dose CTA protocol in comparison with a standard protocol. Methods: Forty patients with recumbent ischemic stroke were included in the study, twenty of whom underwent lowdose CTA, and the remaining twenty underwent a standard CTA protocol of the carotid arteries. Results: No significant difference was found between the mean values of CT number (Hounsfield unit), signal-to-noise ratio, contrast-to-noise ratio, and subjective assessment of image quality in the comparison of the control and experimental groups. CT dose index, volume, and dose length product were significantly lower in patients who underwent lowdose carotid CTA. There was no significant difference in the degree of carotid stenosis between color Doppler and CTA. Conclusion: The use of the low-dose protocol for carotid CTA allows the application of this method in risk groups, in which it was previously not possible to perform, with the same image quality in comparison with the standard protocol.

More recently modified stainless steels have been used to produce various structural elements that work in complex operating conditions. Stainless steel X8CrNiS18-9 (standard EN 10088-3) is the most commonly used from the group of austenitic stainless steel in terms of machinability. This steel has high mechanical and working properties thanks to a complex alloying, primarily with elements such as chromium and nickel. The content of sulphur present in the steel from 0.15 to 0.35% improves machinability. However, sulphur at the same time decreases the mechanical properties, particularly toughness. In steel, tellurium stabilizes carbides and reduces the microporosity of the structure. Also, tellurium is now recognized as a powerful sulphur modifier as well as a machinability additive when used in combination with lead and sulphur. This work aims to determine the influence of tellurium on the machinability, corrosion resistance and mechanical properties of the mentioned steel.

The Zenica tunnel is located as part of the highway on the Vc corridor, Ponirak section-southern exit from the Zenica tunnel. The tunnel is a two-tube with a length of about 3.300 meters. During the excavation of the Zenica tunnel, large amounts of groundwater were recorded in several sections in both tunnel pipes, from wet to flowing. During the tunnel excavation, the engineering-geological data on the rocks through which the excavation was carried out was regularly recorded, and on the basis of these data, the RMR classification of the rock mass was determined. The paper presents one of the possible solutions to control the inflow of groundwater during tunnel excavation by making subhorizontal wells and installing self-drilling anchors for the purpose of directing groundwater into drainage pipes or tunnel sides. The main goal of controlling the groundwater inflow is to reduce the impact of groundwater on further tunnel excavation and to modify the category of rock mass (additional benefit), and thus to reduce the unit price of tunnel excavation.

The research was conducted on 3644 students (1891 male respondents and 1753 female respondents). The goal of the research was to determine the degree and differences in the degree of nutrition and body composition between boys and girls from the 2nd to the 9th grade of elementary school. Based on the obtained results, a t-test for small independent samples, it was determined that there are no statistically significant differences between the male and female respondents in the level of nutrition and the skin fold on the stomach (suprailiac), and for basal metabolism, percentage of body fat, skin fold upper arms (triceps), skinfold on the back (subscapular), the differences are statistically significant. It was determined that out of a total of 1891 (52.00%) male respondents, 180 (9.52%) of them fall into the category of obese, 46 (2.43) boys into the category of excessive nutrition, 804 (42.52%) boys are normally well-nourished, while 861 (45.53 %) of boys malnourished. Out of a total of 1753 (48%) girls, 161 (9.18%) are obese, 38 (2.17%) are undernourished, 717 (40.90%) are normally well-nourished, while 837 (47.75%) are malnourished. Based on the body mass of students from the 2nd to the 9th grade of elementary school, recommendations for daily water intake (liters) are given. The recommendation for the average daily intake of water in liters for all boys is 1.45 and for girls 1.42. The obtained data indicate a problem today caused by bad lifestyle habits. Today's big problem is not only obesity among children but also malnutrition, which was most common among students from the 2nd to the 9th grade of elementary school. It is necessary to act preventively on time and perform more frequent measurements of elementary school-aged students to make changes and proper growth and development. It is necessary to motivate students more to play sports and change the quality and way of their lives. What we miss in childhood is hard to make up for later. [ABSTRACT FROM AUTHOR]

Background and Study Aim. The nutritional status of children can be assessed on the basis of clinical examination, laboratory procedures and anthropometric measurements. Height and body weight are most often used to determine nutrition. Children and adolescents who are at risk of being overweight often also become obese adults. Material and Methods. The research was conducted on a sample of 136 students (67 boys and 69 girls), with an average age of 11.56 years. The aim of the study was to determine the degree and differences in the degree of nutrition and body composition in boys and girls of pubertal age. Results. Based on the obtained results, T-test for small independent samples, it was determined that there are no statistically significant differences between boys and girls, both in the degree of nutrition and body composition, estimated by 10 variables using bioelectric impedance InBody 720. Also, it was found that 19.70% of boys are obese, as well as 17.40% of girls. Cumulatively with the percentage of malnourished respondents, a total of 61.50% of boys were not normally fed, as were 37.70% of girls. The obtained results indicate the need for a more extensive review of the analysed segments and a significantly larger sample of respondents, in order to act preventively in the fight against obesity, as the leading epidemiological health problem of today. Conclusion. It is obvious that physical activity based on physical education classes is not sufficient or is not sufficiently represented to meet the challenges of the modern way of life of children.

Some specific aspects in the state of art regarding the improvements related to I-beams and parallel flanged I-beams production are presented in this paper. One practical solution in the variety of the conversions of the classical to the universal rolling stands is described in some more detail, as well as an overview of the latest improvements in I-beams and parallel flanged I-beams production in the world. So-called INP I-beams have tapered flanges v.s. parallel flanges concerned with parallel flanged I-beams, which are very difficult to be produced on classical rolling mills stands, but much easier and better to be produced on so-called universal rolling stands. Since the universal stands are expensive and are very difficult to fix at the existing rolling mills with classical rolling stands, then a conversion of classical to the universal rolling mills stands is the cheapest satisfactory solution. In a short overview are as well presented state of art technological improvements in parallel flanged I-beams production.

Computed tomography (CT) is a diagnostic imaging process that uses ionising radiation to obtain information about the interior anatomic structure of the human body. Considering that the medical use of ionising radiation implies exposing patients to radiation that may lead to unwanted stochastic effects and that those effects are less probable at lower doses, optimising imaging protocols is of great importance. In this paper, we used an assembled 3D-printed infant head phantom and matched its image quality parameters with those obtained for a commercially available adult head phantom using the imaging protocol dedicated for adult patients. In accordance with the results, an optimised scanning protocol was designed which resulted in dose reductions for paediatric patients while keeping image quality at an adequate level.

Steel 17-7PH is austenitic-martensitic steel with high strength, hardness, and resistance to creep, and corrosion. It is designed for aerospace components, but can also be used for other applications that require high strength and corrosion resistance, as well as leaf springs for operation at temperatures up to 316 °C. It can be used in a solution-treated or heat-treated state to obtain a wide range of property values. This paperwork shows that modification of the contents of alloying elements with a narrower interval of Cr, Ni, and Al can be obtained from austenitic-martensitic steel 17-7PH which by, a subsequent heat treatment, can have values of mechanical and chemical properties required for components of an automotive engine. Chromium is an alphagenic alloying element that stabilizes the ferrite region, nickel is a gammagenic alloying element that stabilizes austenite and gives these steels good strength and toughness, even at low temperatures and aluminum increases corrosion resistance in low-carbon corrosion-resistant steels Research has determined the most suitable interval of Cr, Ni, and Al, which in combination with the cryogenic heat treatment RH950 at -50 °C gives the mechanical and chemical properties that meet the requirements for steel with standard chemical composition. [ABSTRACT FROM AUTHOR]