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The application of circular economy principles in water supply systems has been increasingly studied recently. Concrete experiments and practical implementations in the industry are being carried out with the aim of cost savings, energy production, and material and energy recovery from wastewater treatment processes. In this context, the aim of this paper is to identify some measures that water utilities can take to enhance sustainability and reduce environmental impact. The paper provides a brief overview of the opportunities for water utilities to act on water, materials, and energy.

The analyzes carried out in this research were performed on meadow and mountain honey samples from Bosnia and Herzegovina. The geographical origin of the analyzed honey samples is the area of Mount Majevica in the Tuzla Canton and the area of Livno, Canton 10, Sarajevo, Sarajevo Canton and Vlašić, Central Bosnia Canton. Honey samples were collected from 8 different localities. During the analysis, all honey samples were up to one year old. With the aim of testing the antioxidant capacity of honey, the polyphenol content and total antioxidant capacity were determined. The total antioxidant capacity of honey was determined by the indirect FRAP (Ferric Reducing Antioxidant Power) method, and the polyphenol content by the Folin-Ciocalteu method. The results showed that there is a significant correlation between the antioxidant capacity of the analyzed honey samples and the content of polyphenols in them. In order to compare the antioxidant activity and polyphenol content of pure honey samples (without additives) with honey mixtures (additions: ginger, garlic, sweet wormwood, propolis), mixtures were prepared for all samples, namely 5 mixtures of honey and ginger; 5 mixtures of honey and garlic, 5 mixtures of honey and sweet wormwood and 3 mixtures of honey and propolis. Analyzing the results, a comparative analysis of the polyphenol content and total antioxidant capacity in honey samples before and after the addition of wormwood, ginger, garlic and propolis was performed, and the influence of the mixture's standing time on the tested parameters was also examined. The results of these analyzes showed that additives to honey significantly affect its antioxidant activity and polyphenol content, and that standing the prepared mixtures can lead to an additional increase or decrease of the tested parameters.

Adhesive bonding is a well-established technique for joining materials. This article deals with the challenges of bonding metals, such as aluminium alloy EN AW-5754. To improve the strength of bonded joints, suitable surface preparation prior to bonding is essential. In this work, the surface of the aluminium alloy using three different epoxy adhesives was subjected to two different methods of surface preparation, such as laser cleaning and sanding by hand with sandpaper. The adhesion properties of the bonded surface were determined by measuring the surface roughness parameters (Ra and Rz) for different surface preparations as well as the mechanical property (tensile lap-shear strength). It was found that the bond strength of the aluminium alloy changed depending on the surface preparation and adhesive used, indicating that using the same adhesive and material with different preparation methods can lead to significant variations in bond strength. Therefore, choosing an appropriate surface preparation method that is suitable for the parts to be bonded and their surface roughness is crucial as it increases the strength of the bonded joints.

The additive technologies such as 3D printing are an important part of all branches of industry, primarily due to the possibility of production parts with complex geometries. The aim of the research presented in this paper is the analyze of joining 3D printed polymer parts with adhesive. Furthermore, the aim of this research is to analyze the strength of lap adhesive joints under different loads. FDM technology, PLA materials and two-component epoxy adhesive were used to fabricate the testing specimens.

This paper aims to present the effects of the MIG welding on the mechanical properties of a buttwelded joint of dissimilar aluminium alloys 2024-T351 and AA 6082-T6. Aluminium alloy 6082 T6 is well weldable by classical fusion welding processes (MIG and TIG), while aluminium alloy 2024-T351 is almost non-weldable. For the welding of these two Al alloys, the MIG welding was used on an 8 mm thick sheet using filler material 4043A (AlSi5) and a mixture of argon and helium as a shielding gas. The influence of MIG welding on the obtained structure and mechanical properties of the welded joint was analyzed. The assessment of the mechanical properties of the welded joint of dissimilar Al alloys was performed by Vickers hardness testing, tensile and bending tests of the welded samples.

In this paper, the variability of morphological (stem height, stem basal diameter, proportion of pith, wood and bark) and wood anatomical characteristics (fiber length, fiber diameter, fiber lumen diamater, double cell-wall thickness, vessel diameter, wood rays width and height) of three Salix alba clones (B-44, 347 and NS 73/6) and one Salix viminalis clone both in the control plot and in the site contaminated with a mixture of heavy metals (As, Cd, Cr, Cu, Ni, Pb) was investigated. The observed results showed that individuals of all four clones had significantly higher average values of stem height and stem basal diameter at the control plot compared to the polluted site. As for the proportion of pith, bark and wood, heavy metals caused an increase in the share of pith and a decrease in the share of bark and wood in all clones with the exception of clone NS 73/6. The analysis of wood fiber dimensions showed that the values of all parameters were higher at the control site with the exception of fiber lumen diameter where higher values were observed for clones B-44 and NS 73/6 at the polluted site. Higher values of vessel diameter were recorded for all clones at the control plot, while wood rays width of all individuals was greater at the contaminated site. Regarding the wood rays height, only Salix viminalis showed higher value at the polluted site. These results confirmed that pollution-induced heavy metal stress significantly altered the morphological and wood anatomical characteristics of all researched clones and that it may affect their utility properties.

Given the undeniable clinical and prognostic value, the function of the left atrium (LA) plays a leading role in the contemporary evaluation of cardiac diseases and is considered an essential morphological substrate for the development of cardiovascular diseases. It is sensitive to nervous, endocrine, and immunological stimuli. New evidence from the literature highlights the importance of fibrotic, electrical, and autonomic remodeling of the LA, introducing the concept of atrial cardiomyopathy, which is closely associated with atrial fibrillation and stroke. In the past, the diameter of the LA was the most important parameter for assessing its characteristics, but new information about the various roles of the LA has created the need for parameters that more precisely or thoroughly evaluate LA function. The function of the LA is complex, consisting of three phases: the reservoir phase (ventricular systole), the conduit phase (early diastole), and the pump phase (late diastole). The introduction of myocardial deformation analysis, or strain of the LA via speckle tracking, has achieved significant progress in detecting even subtle functional abnormalities before an increase in LA size. This method improves the diagnostic capabilities of standard echocardiographic examinations, and its diagnostic and prognostic value is sometimes comparable to more advanced and less accessible techniques such as cardiac magnetic resonance imaging and computed tomography.

Pediatric arrhythmology deals with studying of frequency and regularity of heart rhythm disorders in childhood. Rhythm disturbances (dysrhythmias, arrhythmias) occur as a result of disturbances in the creation or conduction of stimuli in the specific or working musculature of the heart. Simplifying the knowledge of everyday work on pediatric arrhythmias, they can originate from the atria of the heart when we speak about supraventricular arrhythmias or from the heart chambers when we talk about ventricular arrhythmias. There are currently three major problems that burden pediatric cardiologists and pediatric arrhythmologists, and which are the focus of interest in pediatrics as a whole. These are primarily sudden cardiac death in children (SCD), fetal arrhythmias (FA) and postoperative-incisional arrhythmias (IA). The development of pediatric arrhythmology is imperative in the development of pediatrics and pediatric cardiology.