Background Periapical lesions are primarily caused by infections in the root canals. The objective of this study was to assess the antibacterial effectiveness of diode laser during root canal treatment in artificial models of infected periapical lesions. Material/Methods One hundred twenty-two extracted premolar single-rooted teeth were inserted into methyl methacrylate artificial models of periapical lesions, and bacterial solutions of Enterococcus faecalis (ATCC 29212) and Streptococcus mitis (ATCC 49456) were then applied to the models. The respective diameters of lesions in the artificial models represented 3 different subgroups based on lesion size. The laser protocol used for endodontic disinfection had a power output of 1.5 W and a wavelength of 810 nm. The impact on cell viability was evaluated by flow cytometry. Results Disinfection with laser did not differ between microorganisms (P=0.137), and laser irradiation with a longer duration had better disinfecting action for both microorganisms (P<0.001). Compared with larger lesions, smaller lesions had a higher percentage of dead cells for both microorganisms (P<0.001). The percentage of dead cells in the treatment groups was significantly higher than in the control group (P<0.001). Conclusions Laser treatment had a poor, almost negligible effect on elimination of bacterial cells in large periapical lesions. Application of a laser might serve as an adjuvant method to standard irrigation with sodium hypochlorite.

Abstract This paper deals with the story and experiences of setting up a new start-up company with the ambition to scale using a software-based product. The paper is written by researchers for researchers interested in doing the same thing. The paper concludes that it can be very beneficial for research as the startup-can be seen as a data collection machine, but to set up a start-up company, comes with unforeseen problems along the way. A few of them involves: Do not rely on rational arguments (only), when marketing your product. Expect long lead-times. Work with multiple threads and secure funding early to ensure that you can finance your startup. Finally, you need to be committed, and you have to have a strategy to manage both your research and your commercial activities.

The COVID-19 pandemic, or better known as the coronavirus pandemic, brought many challenges in education, and one of them was the transition to online teaching, that is. use of information and communication technologies in teaching. Information technology is a term that describes parts (hardware) and programs (software) that allow access to download, organize, manipulate and present information electronically, and communication technology (CT) is a term that describes telecommunications equipment that can send, receive information, search and access them. This research aimed to examine the subjective experience of teachers about personal competencies in the use of information and communication technology in teaching. The population of this research consists of primary school teachers in the area of Tuzla Canton, and the total sample consists of 138 respondents. An anonymous internet survey was used, which is distributed with the help of social networks “Facebook” and a Facebook group called “Prosvjeta TK”, which brings together educators from the Tuzla Canton area. In this paper, we assume that teachers assess their information and communication competencies as positive and they consider themselves competent in their use in the teaching process. It also explores aspects of teachers’ digital competencies as essential competencies for 21st-century education. The paper will provide insight into the personal perception of teachers regarding ICT competence, which is included in the fund of previous knowledge and theoretical knowledge. The results of this research could help understand and analyze further practices, decide on further steps to build teachers’ ICT competencies in and for the future of the school.

In this text, we analyze the presence of dramatic texts in the teaching of literature based on the previous experiences from the Curricula, as well as the current presence of dramatic texts in the Curriculum for the Sarajevo Canton. In the science and methodology of literature education, the issue of a lack and insufficiency of the dramatic genre in literature teaching has been recognized for a long time. Our objective is to present how dramatic texts may and have to be more present in teaching through more significant inter-subject correlation. Thereby the importance of scene education is emphasized, which is primarily acquired in the literature and language teaching, but it may be applied in the teaching of other subjects as well.

The scoring of sleep stages is an essential part of sleep studies. The main objective of this research is to provide an algorithm for the automatic classification of sleep stages using signals that may be obtained in a non-obtrusive way. After reviewing the relevant research, the authors selected a multinomial logistic regression as the basis for their approach. Several parameters were derived from movement and breathing signals, and their combinations were investigated to develop an accurate and stable algorithm. The algorithm was implemented to produce successful results: the accuracy of the recognition of Wake/NREM/REM stages is equal to 73%, with Cohen's kappa of 0.44 for the analyzed 19324 sleep epochs of 30 seconds each. This approach has the advantage of using the only movement and breathing signals, which can be recorded with less effort than heart or brainwave signals, and requiring only four derived parameters for the calculations. Therefore, the new system is a significant improvement for non-obtrusive sleep stage identification compared to existing approaches.

This paper presents some of our first experiences and findings in the ARPA-E project ReNew100, which is to develop an operator support system to enable stable operation of power system with 100% non-synchronous (NS) generation. The key to 100% NS system, as found in many recent studies, is to establish the grid frequency reference using grid-forming (GFM) inverters. In this paper, we demonstrate in Electro-Magnetic-Transient (EMT) simulations, based on Hawai'i big island system with 100% NS capacity, that a system can be operated stably with the help of GFM inverters and appropriate controller parameters for the inverters. The dynamic security optimization (DSO) is introduced for optimizing the inverter control parameters to improve stability of the system towards N-1 contingencies. DSO is verified for five critical N-1 contingencies of big island system identified by Hawaiian Electric. The simulation results show significant stability improvement from DSO. The results in this paper share some insight, and provide a promising solution for operating grid in general with high penetration or 100% of NS generation.

Cyclotides are plant-derived disulfide-rich peptides comprising a cyclic cystine knot, which confers remarkable stability against thermal, proteolytic, and chemical degradation. They represent an emerging class of G protein-coupled receptor (GPCR) ligands. In this study, utilizing a screening approach of plant extracts and pharmacological analysis we identified cyclotides from Carapichea ipecacuanha to be ligands of the κ-opioid receptor (KOR), an attractive target for developing analgesics with reduced side effects and therapeutics for multiple sclerosis (MS). This prompted us to verify whether [T20K]kalata B1, a cyclotide in clinical development for the treatment of MS, is able to modulate KOR signaling. T20K bound to and fully activated KOR in the low μM range. We then explored the ability of T20K to allosterically modulate KOR. Co-incubation of T20K with KOR ligands resulted in positive allosteric modulation in functional cAMP assays by altering either the efficacy of dynorphin A1–13 or the potency and efficacy of U50,488 (a selective KOR agonist), respectively. In addition, T20K increased the basal response upon cotreatment with U50,488. In the bioluminescence resonance energy transfer assay T20K negatively modulated the efficacy of U50,488. This study identifies cyclotides capable of modulating KOR and highlights the potential of plant-derived peptides as an opportunity to develop cyclotide-based KOR modulators.

The Bosnian-Herzegovinian drama was occasionally performed on the Czechoslovak and Czech stages. The plots were not systematically translated, nor cultural-artistic contacts were planned, especially when it came to the twentieth century. With the arrival of students in the Czech Republic in the last two decades, systematic translation began, various stage readings were organized and Bosnian-Herzegovinian literature, including drama, began to be published. In the history of Czech theater, Ahmed Muradbegović was the first Bosnian dramatic who was tagged in Czechoslovakia, while the audience could also read contemporary playwrights, which were either published (Bašović, Imširević) or represented by theater agencies (Bukvić, Karahasan, Milenić, Šljivar). Text adaptations of Bosnian authors, dramalets, performances, and various stage events are presented and held in the Czech Republic thanks to the Bosnian community in Prague.

Before the socio-political communities are posted, a very demanding task of defining the subject on whose name will behalf political power is implemented over a given state territory. However, the question about the subject of sovereignty should in no case be misunderstood as an issue of simply theoretical approach. The level of a state’s democracy, as well as its ability to realize internal and external sovereignty, depends entirely on fact: does the power belong to the People and whether it derives from the People. In other words, the issue of popular sovereignty is a substantial, constitutive element of modern democratic states. When we speak about contemporary Bosnia and Herzegovina, the functionality of the entire state government is often hindered by the complex decision-making processes at all state levels which lead to obstruction of the entire decision-making process. Such a dysfunctional decision-making process on the state level poses a threat and disables the Bosnian plural society to respond to the modern challenges of a democratic functioning state. The legal nature of Bosnian society is determined by the existence of constituent people who have “usurped” the entire decision-making process. There is still no end in sight to the struggle that leads to an oligarchy of the ruling elites; furthermore, there is still no appropriate socio-political mechanism that will enhance the accountability of the representatives to their voters; it is still inconceivable that decisions of state authorities are effectively and consistently implemented throughout the national territory. In other words, there is still no appropriate mechanism that will enhance the principle of popular sovereignty. It is necessary to “offer” Bosnia and Herzegovina’s pluralism and its political tradition a form of democratic authority which in no way should be a cliché. Furthermore, it may not be one of the “copy-paste” models of democratic authority. Currently, citizens of B&H are completely suspended (de facto, there are only citizens of entities). In the Federation of Bosnia and Herzegovina Serbs are suspended, while in the Republika Srpska, Bosniacs and Croats cannot equally participate in the decision-making process. An unfinished process of implementation of the Dayton Agreement and, in particular, Annex 4 (the Constitution of B&H), whose provisions permit discrimination against the citizens of Bosnia and Herzegovina (the impossibility of the realization of the principle of equality in the exercise of universal suffrage), as well as the non-application of the Decision of the European Court of Human Rights contributes and is conducive to further segmentation of Bosnian society.

With the development of technologies, virtual interaction contributes to the stronger virtual socialization of young people. This paper aims to examine how the virtual world influences the identity of young people. In the introduction, we reviewed the studies that dealt with virtual socialization, and then we presented a brief empirical insight into today’s socialization of young people from 14 to 21 years of age. With the questionnaire, we tried to examine the “quality” of virtual socialization in the lives of young people. The tasks of our research are focused on questioning the values that young people adopt through virtual socialization, an assessment of the “image of their own” that is in the virtual world, and the compatibility of the virtual identity with the one built in the family and peer environment. Respondents expressed views that their lives matched a life that points to social networks, while they felt that their peers did not live a life that they sought to portray on social networks. The results showed that they feel more secure in online communication than in life. Also, opinions are that the values they adopt are influenced by public opinion, etc. We can conclude that educating youths about the virtual world should be in several directions: actuality, truthfulness, privacy, and freedom.

The increasing penetration of inverter-based resources (IBRs) is changing grid dynamics and challenging grid planning, operation, and protection. Particularly, the increasing integration of IBRs may drive the power grid towards weak grid conditions, where potential dynamic stability issues may become significant. Recently, it was reported that the unintended loss of solar generation occurred in Southern California over a large geographic area. One of the major reasons for this generation loss is the tripping of solar generators due to the overvoltage in a less than one cycle time frame (i.e., sub-cycle overvoltage) experienced by solar photovoltaic (PV) inverters, especially when solar PV inverters enter the momentary cessation operation mode in response to abnormal grid disturbances. In this paper, the impact of grid strength on sub-cycle dynamics resulting from momentary cessation is investigated in a power system with distributed solar PV integration. In this investigation, distributed solar PVs are modeled with detailed grid-following inverter models considering inverter switching dynamics and momentary cessation function. It is found that undesired sub-cycle overvoltage has a positive relation to grid strength at points of integration (POIs) of solar PVs. At the weak POIs, server sub-cycle overvoltage occurs not only when momentary cessation starts to cease energy injection but also when momentary cessation restarts to inject energy into the system during the restoration process. Furhtermore, the interaction between solar PVs making POIs weak exacerbates the severity of the sub-cycle overvoltage at the POIs. Thus, in the power system with high penetration of solar PVs, it is important to improve grid strength in power system planning and quickly recover grid strength in power system operation following disturbances.