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In this study, the research focuses on tensile PA12 specimens with CAD model dimensions selected according to the ISO 527-2 standard, with bulk dimensions of 170x20x4 mm. The study utilizes a Fuse 1 (FormLabs, Summerville, MA) 3D printer that employs SLS technology. This printer is capable of producing objects with different shapes and dimensions simultaneously, provided that they are printed at a minimum distance of 5 mm apart. The research involves producing two batches of specimens, each differing in printing orientation (i.e., horizontal and vertical). After printing, the specimens are tested using a Shimadzu AGS-X universal testing machine with a capacity of 100 kN to evaluate the mechanical characteristics of the materials. The findings reveal that horizontally printed specimens have a modulus of elasticity about 9.3% higher than the manufacturer's stated value, while vertically printed specimens show an increase of approximately 11.4%. This enhancement is likely due to the thermal and cooling cycles during printing. The difference in modulus of elasticity between the orientations is around 2%, indicating a minor impact on mechanical properties.

This research aims to determine how the orientation and placement of printing impacts the compressive strength of specimens manufactured by Selective Laser Sintering (SLS). The research includes compressive specimens in which the CAD model dimensions are selected according to the ISO 604 standard, and specimen geometry Ø10x20 mm in bulk. All specimen configurations are additively manufactured in two different printing orientations, horizontal and vertical, and printed in the middle and on the edge of the powder bed. All specimens are additively manufactured using Polyamide 12 (PA 12) material on a Fuse 1 device (FormLabs, located in Summerville, MA). Compressive strength testing was carried out using a Shimadzu AGS-X universal testing machine (Shimadzu Corp., Kyoto, Japan).

Fourteen donepezil-like acetylcholinesterase (AChE) inhibitors from our library were analyzed using reversed-phase thin-layer chromatography to assess their lipophilicity and blood–brain barrier permeability. Compounds possessed N-benzylpiperidine and N,N-diarylpiperazine moieties connected via a short carboxamide or amine linker. Retention parameters RM 0, b, and C0 were considered as the measures of lipophilicity. Besides, logD of the investigated compounds was determined chromatographically using standard compounds with known logPow and logD values at pH 11. Experimentally obtained lipophilicity parameters correlated well with in silico generated results, and the effect of the nature of the linker between two pharmacophores and substituents on the arylpiperazine part of the molecule was observed. As a result of drug-likeness analysis, both Lipinski's rule of five and Veber's rule parameters were determined, suggesting that examined compounds could be potential candidates for further drug development. Principal component analysis was performed to obtain an insight into a grouping of compounds based on calculated structural descriptors, experimentally obtained values of lipophilicity, and AChE inhibitory activity.

Serotonin, or 5-hydroxytryptamine (5-HT), is a biogenic amine most noted as a neurotransmitter, an activator of the utmost subtype family of G-protein- coupled receptors (GPCR). Drugs targeting 5-HT1A and other 5-HT receptors treat central nervous system diseases such as schizophrenia and depression. Recent advances in serotonin receptor structure research gave us several crystal 5-HT1A receptor structures, most notably 5-HT1A bound to the antipsychotic drug aripiprazole (Abilify®). This discovery prompted us to evaluate a series of newly synthesized ligands for serotonergic activity since those arylpiperazine derivatives share minimal general structure with aripiprazole. The results of molecular docking analysis of unsubstituted starting substances encouraged us to propound further modifications of the tail and head parts of the parent molecules to maximize receptor binding affinity. Intrigued by the results of molecular analysis, all foreseen derivatives were synthesized. The pharmacological activity of all nine (5a and 6a are synthesized previously) compounds was assessed by the in vitro tests and in silico pharmacokinetics predictions for the most promising candidates. All tested ligands have improved affinity compering to parent compounds (10a and 11a), 8b and 9b expressed the best pharmacological profile with an improved binding affinity toward serotonin 5-HT1A receptors (Ki 12.1 and 4.8 nM, respectively).

Informacija predstavlja najvažniji element za donošenje odluka u poslovanju, turizmu, poljoprivredi i ekonomiji. U ovom radu korišćene su metode pronalaženja, selektoanja i organizacije naučnih informacija. Koncept Internet stvari (eng. Internet of Things - IoT) je nastao, povezivanjem različitih uređaja, vozila, infrastrukturnih elemenata i sl. pomoću interneta radi njihove međusobne komunikacije sa drugim uređajima i ljudima. Internet stvari je skup međusobno povezanih pametnih uređaja koji omogućavaju međusobnu komunikaciju i komunikaciju sa okolinom. Iternet of things su dio savremene tehnologije koji olakšava donošenje odluka kompanijama i poljoprivrednicima. Internet stvari koriste internet i pametne urađaje za pružanje inovatinih rješenja u poslovanju preduzeća, u ekonomiji država, u poljoprivredi i u drugim oblastima. U ovome radu fokusiraćemo se na primjenu Internet stvari u poslovanju preduzeća, turizmu, poljoprivredi i ekonomiji uopšte., Information is the most important element for decision-making in business, agriculture, tourism and economics. Methods of finding, selecting and organizing scientific information were used in this paper. The concept of the Internet of Things (IoT) emerged by connecting different devices, vehicles, infrastructure elements, and the like via the internet for their mutual communication with other devices and people. The Internet of Things is a set of interconnected smart devices that enable mutual communication and communication with the environment. IoT is a part of modern technology that facilitates decision-making for companies and farmers. IoT uses the internet and smart devices to provide innovative solutions in business enterprise, state economics, agriculture, and other fields. In this paper, we will focus on the application of IoT in business enterprise, agriculture, and economics in general.

Considering that additive manufacturing technology, has evolved significantly over the past few decades, understanding of materials mechanical properties became important part of researches with the goal of further improvement of production Among the seven different AM technologies, in this research is used digital light processing (DLP) 3D printing process with LCD projector. The thermoplastic polymer material acrylonitrile butadiene styrene (ABS) is a widely used material for 3D plastics printing, and in this study, it is chosen in the resin form. So far, this type of material has not been sufficiently studied, and the aim of this study was to determine the mechanical properties for two different specimens’ building orientations (45° and 90°). Specimen’s geometry is chosen according to the respective standards for mechanical testing’s. Because of the difficulties and warping which occur when printing the flat, thin and long specimens, orientation ‘on edge’, i.e., 90° is chosen, as well as the 45° orientation, for comparison. Tensile, three point bending and compression mechanical tests were performed and Matlab is used to create stress-strain curves. Additionally, microscopy is performed for more comprehensive insight of the behaviour of the ABS resin printed via DLP-LCD technology. Comparison of mechanical properties for two orientations leads to the overview of printing parameters which result in better mechanical properties regard to specific application. Better behaviour and compression mechanical properties are noticed in 90° orientation printed ABS resin specimens, compared to 45° ones, while flexure behaviour of ABS is the same regardless to building orientation.

A continuous and sufficient supply of top-quality water is imperative for the proper development and survival of bees. Beekeepers often rely on a variety of water containers, each afflicted with numerous shortcomings such as limited capacity, irregular water availability, and subpar sanitation. This analysis aims to investigate the different categories of bee drinkers essential for meeting the water needs of bees. Additionally, we will conduct an in-depth examination of the pros and cons associated with each type of waterer to gain insights into their effectiveness and their impact on bee colonies. Ultimately, we will determine the most suitable waterer for the unique conditions and demands of beekeeping operations.

SLS technology is a popular choice in various industries worldwide because of its ability to produce complex geometry components with less effort when compared to conventional methods. The technology involves using materials in powder forms, such as polyamides (PA), polystyrenes, thermoplastic elastomers, and polyaryletherketones. In this study, the research focuses on compressive PA12 specimens with CAD model dimensions selected according to the ISO 604 standard, with bulk dimensions of Ø10x20 [mm]. The study utilizes a Fuse 1 (FormLabs, Summerville, MA) 3D printer that employs the SLS technology. This printer is capable of producing objects with different shapes and dimensions simultaneously, provided that they are printed at a minimum distance of 5 [mm] apart. The research involves producing four batches of specimens, each differing in printing orientation (i.e., horizontal and vertical) and printing location (i.e., printed on the edge and in the middle of the powder bed). The printed specimens are scanned, and the obtained scans are compared with the original CAD model in the GOM Inspect program. The highest deviations in all four specimen series are in height, ranging from 0.1 up to 0.15 mm. In the case of vertical specimens printed in the middle of the powder bed, there are also deviations in the width of the specimen.

Fourteen novel N-benzylpiperidine and N,N-diarylpiperazine conjugates were synthesized and pharmacologically evaluated as donepezil analogs, in a ligand-based drug design approach. All compounds possessed high to moderate in vitro inhibitory activity with IC50 in range 2.3–20 µM and selectivity towards acetylcholinesterase, while being inactive towards butyrylcholinesterase. Structure-activity relationship analysis revealed the influence of N,N-diarylpiperazine moiety and the linker connecting two pharmacophores on the inhibitory activity. Kinetic studies on the two most active compounds 7g and 8g (IC50 = 2.3 and 4 µM, respectively) revealed mixed type mode of inhibition, binding to both, free enzyme and enzyme-substrate complex. For further understanding of mechanism of action and binding orientations, molecular docking was performed for all compounds, while the ligand transport simulation and molecular dynamics simulations were performed for 7g and 8g. Computational results corroborated well with in vitro activities and kinetic studies.

The aim of this paper is to determine the mechanical characteristics of parts obtained by Additive Manufacturing (AM). All specimens were printed on a Fuse 1 (FormLabs, Summerville, MA) 30 printer. This AM technology is SLS (Selective Laser Sintering). With this technology, objects of different shapes and dimensions can be produced at the same time. The only condition is that during printing, the parts must be at least 5 [mm] apart from each other. The thickness ofthe powder layer during printing was 110 microns. In this paper, one type of specimens are used to determine the mechanical characteristics, the dimensions of which were chosen according to specific standard. This standard is ISO 178 for 3-point bending specimens. The dimensions of the bending specimens are 96x8x4 [mm]. These specimens were produced in four batches, differing in printing orientation (horizontal and vertical) and printing location (printed on the edge and in the middle of the powder bed). The material used for printing the specimens is polyamide (PA 12). The flexural strength of this material is 66 MPa. After printing, specimens were tested on a standard tensile testing machine (SHIMADZU AGS-X 100kN). In the case of vertical bending specimens printed in the middle, the flexural strength after the test was 65.15 MPa, and for this type of specimens this is the smallest deviation from the value given in the literature. The greatest deviations of the flexural strength values are for vertical specimens printed on the edge, where the flexural strength is 58 MPa, and for horizontal specimens printed in the middle, the flexural strength is 81.7 MPa.