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Background: A precise three-point shot (3S) is considered a key parameter of success in a basketball game, and therefore the factors that affect its success have always attracted the attention of researchers. Aim: The aim of this research was a biomechanical-mathematical analysis of 3S in basketball, in order to determine the key parameters for performing a 3S. Results:  The research shows a model of shooting a basketball player from the central position of the shot with 6.75 m. The modeling led to the conclusion that the height of the throw, the speed and the angle of the throw of the ball have a positive and direct relationship with the angle at which the ball falls into the basket when it comes to a shot for three points. Conclusion:  The height of the throw, the speed and the angle of the ball have a positive and direct relationship with the angle at which the ball hits the basket when it comes to a shot for three points. Anthropometric characteristics of the player, such as the length of the arm, and the height of the player, directly lead to a positive relationship with the throwing angle.

Nisveta Softić, H. Makic, Edisa Trumić, H. Keran, Melisa Ahmetović

One of the most important public- health tasks is to provide hygienic and healthy food and water, which will not have harmful consequences for the health of consumers, and in this way a safe food trade is ensured, therefore protecting everyone in the chain from the producer to the consumer. This paper presents the concentrations of heavy metals Fe, Mn, Zn and Cu, obtained by atomic absorption spectrophotometry (AAS), from 5 samples of thyme infusion (lat. Thymus serpyllum), which can be found on the market of Travnik. Sample infusions were prepared by holding the filter bags in boiling deionized water for 10 minutes. Mean values of concentrations of these heavy metals were for Fe 0.0508 ± 0.0139 mg/kg, Mn 0.06 ± 0.0069 mg/kg, Zn 0.0436 ± 0.0147 mg/kg, while the Cu content was not detected in any infusion of the said tea. The risk assessment of the intake of tested heavy metals for the health of consumers, expressed through the Hazard Index (HI), which was <1, shows that the samples of analyzed teas are safe for consumption.

S. Vegar-Zubović, M. Jusufbegović, D. Bulja, Amila Sidran, M. Bečirčić, Adi Behmen

A fetus with suspicion for holoprosencephaly and various brain malformations were seen on ultrasound and send for magnetic resonance imaging (MRI). Immediately after the birth of the female patient ultrasound and MRI was made which confirmed lobar holoprosencephaly. Fetal MRI stands out as a powerful diagnostic tool for detecting anomalies and other disorders. By developing new sequences and raising image quality will enable visualization of small details.

Purpose Infantile hemangiomas (IH) are the most common benign vascular tumors of infancy. Ocular complications due to orbital IH include strabismal, deprivational, or anisometropic astigmatism, and visual loss secondary to amblyopia. Observations We report a case of a two-month-old female infant with a severe deep orbital IH. The diagnosis was established by clinical examination and magnetic resonance imaging (MRI). The patient was treated with oral propranolol for six months. Complete tumor regression was observed clinically and by MRI following the treatment. The patient showed no adverse effects or tumor recurrence at the 14-month follow-up. Conclusions and Importance Despite its benign nature, periorbital IH requires a rapid diagnosis and prompt treatment to prevent vision loss, particularly in infants. Our case confirms that oral propranolol may be regarded as a safe drug for periorbital IH with an excellent outcome.

This paper examines possibilities for improving the existing strategies of consistency management for highly-distributed transactional database in a hybrid cloud environment. With a detailed analysis of the existing consistency models for distributed database and standard strategies including Classic, Quorum and Tree Based Consistency (TBC), it is concluded that an improved advanced model of so-called visible adaptive consistency needs to be applied in a highly-distributed cloud environment, as necessary and sufficient degree of synchronization of all replicas. Along with the proposed model, research and development of an advanced novel strategy for consistency management Rose TBC (R-TBC) approach has been conducted, by improving standard TBC approach. Regarding implementation, a specific agglomerative Rose Tree Algorithm (RTA) has been developed, based on Bayesian hierarchical clustering and Graph Partitioning Algorithm - Multidimensional Data Clustering (GPA-MDC) intelligent partitioning of transactional Cloud Database Management System (CDBMS). The final result is constructed R-TBC model that changes in accordance with dynamic changes of entire heterogeneous CDBMS environment.

Microneedles (MNs) have been manufactured using a variety of methods from a range of materials, but most of them are expensive and time-consuming for screening new designs and making any modifications. Therefore, stereolithography (SLA) has emerged as a promising approach for MN fabrication due to its numerous advantages, including simplicity, low cost, and the ability to manufacture complex geometrical products at any time, including modifications to the original designs. This work aimed to print MNs using SLA technology and investigate the effects of post-printing curing conditions on the mechanical properties of 3D-printed MNs. Solid MNs were designed using CAD software and printed with grey resin (Formlabs, UK) using Form 3 printer (Formlabs, UK). MNs dimensions were 1.2 × 0.4 × 0.05 mm, arranged in 6 rows and 6 columns on a 10 × 10 mm baseplate. MNs were then immersed in an isopropyl alcohol bath to remove unpolymerized resin residues and cured in a UV-A heated chamber (Formlabs, UK). In total, nine samples were taken for each combination of curing temperature (35°C, 50°C, and 70°C) and curing time (5 min, 20 min, and 60 min). Fracture tests were conducted using a hardness apparatus TB24 (Erweka, Germany). MNs were placed on the moving probe of the machine and compressed until fracture. The optimization of the SLA process parameters for improving the strength of MNs was performed using the Taguchi method. The design of experiments was carried out based on the Taguchi L9 orthogonal array. Experimental results showed that the curing temperature has a significant influence on MN strength improvements. Improvement of the MN strength can be achieved by increasing the curing temperature and curing time.

A. Macken, A. Prkić, N. Vermeulen, I. van Oost, K. Koenraadt, B. The, D. Eygendaal

M. Banožić, A. Jozinović, Jovana Grgić, Borislav Miličević, S. Jokić

Three fractions of tobacco waste (scrap, dust and midrib) were subjected to a high voltage electric discharge (HVED) assisted extraction procedure under different experimental conditions: solvent:solid ratio (300, 500, 700 mL/g), frequency (40, 70, 100 Hz) and treatment time (15, 30, 45 min), in order to study the influence of these conditions on the content of chlorogenic acid. The content of chlorogenic acid ranged from 1.54 to 3.66 mg/100 g for scrap, from 1.90 to 2.97 mg/100 g for dust, and from 2.30 to 3.38 mg/100 g for midrib extract, showing a strong dependence on the applied process parameters. The temperature change and the change in pH and electrical conductivity of the extracts after high voltage discharge treatment were also observed. The studied process parameters showed a statistically significant effect on the chemical and physical properties of the extracts from tobacco waste as well as on the content of chlorogenic acid, indicating the potential of HVED assisted processes in the separation of chlorogenic acid from tobacco industry waste. Multiple regression analysis was used to fit the results for the chlorogenic acid to a second order polynomial equation and the optimum conditions were determined.

L. Gren, K. Dierschke, F. Mattsson, E. Assarsson, A. Krais, M. Kåredal, K. Lovén, J. Löndahl et al.

Background: Diesel engine exhaust causes adverse health effects. Meanwhile, the impact of renewable diesel exhaust on human health is less known. In this study, nasal patency, pulmonary function, and self-rated symptoms were assessed in 19 healthy volunteers after two separate 3-hour exposures to renewable diesel (hydrotreated vegetable oil [HVO]) exhaust, and exposure to filtered air (FA) for comparison. The HVO exposures were generated with two modern non-road vehicles (2019) having either: 1) no aftertreatment system (HVOPM+NOx), or 2) an aftertreatment system containing a diesel oxidation catalyst and a diesel particulate filter (HVONOx). The exposure concentrations complied with current EU occupational exposure limits (OELs) of NO, NO2, formaldehyde, polycyclic aromatic hydrocarbons (PAHs), and future OELs of elemental carbon (EC) from 2023. Results: Exposure to HVOPM+NOx consisted of PM1 (≈90 µg m-3, 54 µg m-3 EC) and NOx (NO 3.4 ppm, NO2 0.6 ppm). The average total respiratory tract deposition of PM1 was 27 µg h-1. The deposition fraction of HVO PM1 was 40-50% higher compared to diesel exhaust PM1 from an older vehicle, due to smaller particle sizes of the HVOPM+NOx exhaust. Exposure to HVONOx consisted mainly of NOx (NO 2.0 ppm, NO2 0.7 ppm) with low level of PM1 (~1 µg m-3). Compared to filtered air, exposure to HVOPM+NOx and HVONOx caused higher incidence of self-reported symptoms (78%, 63%, respectively, vs. 28% for FA, p<0.03). Especially, exposure to HVOPM+NOx showed 40-50% higher eye and throat irritation symptoms. Compared to filtered air, a decrement in nasal patency was found for the HVONOx exposures (-18.1, 95%CI: -27.3 to -8.8 L min-1), and for the HVOPM+NOx (-7.4 (-15.6 to 0.8) L min-1). Overall, no change was indicated in the pulmonary function tests (spirometry, peak expiratory flow, forced oscillation technique), except a slight increase in FEV1/FVC after exposure to HVONOx.Conclusion: Short-term exposure to HVO exhaust below the EU OELs did not cause severe pulmonary function changes in healthy subjects. However, an increase in self-rated mild irritation symptoms, and mild decrease in nasal patency after two HVO exposures may indicate irritative effects from exposure to HVO exhaust from modern non-road vehicles below future OELs.

Physics curricula around the world recognise energy as one of the core concepts in science (Duit, 2014), as it is fundamental in development of integrated scientific understanding of phenomena (Linn et al., 2006; National Research Council, 2012; Nordine et al., 2011). Importance of the energy concept is also recognised by PISA and TIMSS studies and is reflected in many science standards (National Research Council, 2012; Next Generation Science Standards, 2013). However, research about students’ energy conceptions keeps showing that students at all educational levels have significant difficulties with the concept of energy (Goldring & Osborne, 1994; Lawson & McDermott, 1987; Neumann et al., 2013; Pride et al., 1998). Concretely, students exhibit difficulties with understanding work-energy processes (Van Huis & Van den Berg, 1993), energy degradation and energy conservation (Goldring & Osborne, 1994; Liu & McKeough, 2005; Neumann et al., 2013). Thereby, a large number of studies detected conservation of energy as the most difficult aspect of the energy concept (Lindsey et al., 2012; Neumann et al., 2013; Van Heuvelen & Zou, 2001; Van Huis & Van den Berg, 1993). In fact, only a very few students develop deeper understanding of energy conservation until the time they finish secondary school (Herrmann-Abell & DeBoer, 2018). For purposes of improving the quality of teaching about energy, it is useful to identify possible sources of above-mentioned students’ difficulties. Firstly, it is important to note that many students’ difficulties with the energy concept may be related to students’ (mis)understanding of systems (Seeley et al., 2019; Van Heuvelen & Zou, 2001; Van Huis & Van den Berg, 1993). Consequently, students should be helped to recognize the importance of carefully choosing the physical system, if one wants them to gain a functional understanding of energy conservation (Lindsey et al., 2012; Seeley et al., 2019). Such system-based Abstract. Conventional teaching about the law of conservation of mechanical energy (LCME) often results with students trying to solve problems by remembering similar problems they already covered in classes. Consequently, many students fail to transfer their knowledge to simplest real-life problems. Therefore, a pre-test – post-test quasi-experiment was conducted to evaluate the effects of an alternative, system-based approach to teaching about LCME. The study included 70 upper-secondary students from the First Bosniak Gymnasium Sarajevo, Bosnia and Herzegovina. Firstly, all students learned about energy in a conventional way. Then they wrote a test on LCME and had three additional hours of teaching about this topic, where one group of students learned in line with the forces-variant of the system approach (e.g., discussing conservative and nonconservative forces) and the other group with the process-variant of the same approach (e.g., discussing system’s states and processes like in thermodynamics). For both variants, only three hours of system-based teaching proved to substantially improve the students’ level of LCME understanding compared to the level of understanding they had after conventional teaching. It follows that the system approach may work well at the upper-secondary level, if it is introduced through the scaffolding-andfading technique.

G. Gantar, Peter Göncz, M. Kovačič

The press-fit process is an efficient, low-cost method for joining parts. The parts that must be joined interfere with each other’s occupation of space; therefore, contact dimensions and their tolerances influence the quality of the assembly. The traditional method for the selection of contact dimensions and their tolerances is based on engineering experience. The idea of the research work presented in this paper is to optimize the press-fit process at an early stage of development process, involving prediction and optimization of the joining force and consequently the prediction and minimization of the rejection rate. Accordingly, several finite-element (FE) simulations of the press-fit process for predicting the joining forces were conducted, considering input-parameter variations (material properties: yield stress, hardening exponent; geometry: shaft diameter, guide diameter of the core, functional diameter of the core; friction coefficient). Based on FE simulations and 47 different input-parameter-variation results, the empirical model for predicting the joining force using the response-surface methodology (RSM) was obtained. By using RSM and a stochastic Monte Carlo simulation, the rejection rate was also determined. The predicted and the actual rejection rates for selected process parameters were 1.4 % and 1.5 %, respectively. Consequently, the press-fit process can also be optimized to reduce the rejection rate using the same Monte Carlo simulation. The results of the analysis show that the rejection rate can be reduced from 1.4 % to 0.2 %.

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