12 10 3494 https://omeka.ibu.edu.ba/files/original/159cf5c1fa7f997010eac3af1bd557e9.pdf e3a179bb860ad4bdbb799b4e0603013f Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Prevalence of rs2108622 (CYP4F2*3) Single Nucleotide Polymorphism – A Review Author Author Selma Žiga, Hana Efendić, Larisa Bešić Abstract A summary of the resource. Cardiovascular diseases are known to be treated with anticoagulants lifelong. Warfarin is one of the most commonly used medications for anticoagulation despite causing serious side effects in some patients. Different single nucleotide polymorphisms (SNPs) that have a role in the cytochrome P450 system can also affect the metabolism, as well as dosing, of warfarin. The purpose of this review is to look into the prevalence of this SNP in the past research and screen for possible correlations with age, place of origin, family history of cardiovascular and cerebrovascular diseases, or other medical conditions possibly present in various populations. In total, 20 scientific articles falling under the inclusion criteria were reviewed and found usable, and the rest of the cases will be highly beneficial in the upcoming years to determine the role of the recently discovered CYP4F2 rs2108622 variant, as well as the previously known CYP2C9 and VKORC1 SNPs, in the variance of warfarin dose requirement. These findings may also point researchers in the right direction for qualifying and validating these genetic variants for use as GBs (genomic biomarkers) in the clinical and medical practice of treatment with warfarin. Keywords Keywords. SNP, rs210862 (CYP4F2*3) SNP, warfarin, vitamin K, cardiovascular disease, anticoagulation, INR. Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021328 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Literature review https://omeka.ibu.edu.ba/files/original/10c6cd6b9a20e1a1393d9fe312dc243a.pdf b3d96f84062dbe647100f3a16c384236 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Depression and Anxiety Analysis and Prediction using Big Data Technologies Author Author Mersiha Ćeranić, Samed Jukić Abstract A summary of the resource. COVID-19 pandemic brought many changes in people’s lifestyles. Some of those changes hurt people's mental health in different age groups. This research is done to investigate which factors contributed most to the occurrence of depressive and anxiety symptoms during COVID-19 lockdown, and what type of people in terms of age, sex, level of education, place of living, was the most exposed to the appearance of mental health disorders. 1115 people (18-85 years old) from Poland joined the research process. They fulfilled online questionnaires which were used as a basis for further research of lockdown impact on mental health. Responses are evaluated by using ML tools predicting the group of participants with signs of depression and anxiety, based on their answers to the questionnaires, and the attributes of the participants. Based on the results given by the studies, the youngest population (age 18-29), which participated in the surveys, experienced more intense depression and anxiety symptoms than participants from other age groups. Keywords Keywords. Anxiety, covid-19, decision tree, depression, logistic regression, tableau, Weka. Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021327 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Original research https://omeka.ibu.edu.ba/files/original/2681bbb3cd83356e90e4aba0deaae042.pdf 018237549ef606811f81d632873466a0 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Recommendation Engine on IPTV Author Author Vedad Njuhović, Samed Jukić Abstract A summary of the resource. In recent years IPTV (Internet Protocol Television) platforms are becoming one of the most popular entertainment multimedia services which are used to serve movies, tv-series and other video and audio attractive content using the Internet Protocol. VoD (Video on Demand) is the most popular multimedia IPTV service, which provides content without the need for the old traditional way of using video playback devices. Except that it is necessary to have high-quality VoD content, IPTV platforms must provide the best end-user experience. Moreover, it is imperative to provide new features to attract new customers and keep the existing ones. We confirmed the efficacy of this classifier thru simple trial and error. When we searched for movies that have sequels, our engine recommended those sequels. Since Cosine Similarity Classifier considers multiple factors, such as actor, genre, year, etc. Even if the movie does not have prequels or sequels this algorithm was able to provide us with movies that share other common characteristics. Keywords Keywords. IPTV, engine, unicast, broadcast, multicast, python, CSS, HTML, JS. Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021326 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Original research https://omeka.ibu.edu.ba/files/original/531fa16c726b30a5aec6b709913003ea.pdf cc737be78b1a723001dcdbfa17c548fc Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Machine Learning-Based Gene Clustering on Brain Cancer Using K-Means and Hierarchical Clustering Methods Author Author Fatih Yilmaz, Samed Jukić Abstract A summary of the resource. K-means and hierarchical clustering algorithms are employed to cluster genes according to the gene expression to determine the harming level of the genes in brain cancer. The gene expression data with a control group from The Cancer Genome Atlas database were used. The optimal cluster number for each clustering technique was obtained using the elbow method and dendrogram for K-means and hierarchical clustering methods respectively. We identified the ideal number of clusters as three and further classified them into seven groups. We observed that the second cluster contains over half the genes in healthy people and the cluster distribution of a healthy patient and a patient who died six months after being diagnosed with brain cancer is similar. Further analysis indicated that of all the time spent by patients after being diagnosed with brain cancer, group 0 has the highest percentage in one month after the diagnosis, while group -2 has the lowest percentage. Most genes shift their clusters when Kmeans and hierarchical clustering techniques we compared with the genes from the control and disease groups. The result of the measure of dissimilarity between the genes expression patterns indicates that the K-means technique outperforms the hierarchical technique with a higher rate of change in the cluster. Keywords Keywords. Brain cancer, gene clustering, hierarchical clustering, K-means clustering, machine learning. Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021325 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Original research https://omeka.ibu.edu.ba/files/original/9b9af352702f480808cfc7cf8737cb81.pdf baee14a6a0aa63930e7a0c90e038676d Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Prediction of Solved Homicides Using Classification Method Author Author Lamija Zukić, Samed Jukić Abstract A summary of the resource. Homicide rates are still high in the world and they are the worst crime in human existence. Despite all the technological advances and usage of information by various agencies, the number of homicides is not decreasing. Homicide prediction in certain countries should notably be the number one priority, which can help the government to easily identify the kind of profile they are looking for, or even help them prevent those cases. This paper compares different Machine Learning Techniques classifications of homicide prediction. Random Forest (RF), Random Tree, J48, Naive Bayes and k-Nearest-Neighbor (KNN) were tested to determine which method provides the best results in homicide prediction classification. The results of sample accuracy for all algorithms were around 99%, which clearly shows that all algorithms give great results. However, J48 is the best technique applied on the dataset, as it classified all instances correctly. Keywords Keywords. Classification, data analysis, homicide, machine learning, prediction. Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021324 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Original research https://omeka.ibu.edu.ba/files/original/47803e1a263bd6b4f783f59726b172fb.pdf 8395c7aba58aaf5fd5f5cbca54796c01 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Frequency Locked Loop in Estimating Active, Reactive and Apparent Powers Author Author Meris Lihić, Slobodan Lubura Abstract A summary of the resource. In this paper, a new power calculation method has been presented. This method is based on a second-order generalized integrator frequency locked loop (SOGIFLL) and has enhanced features over classical methods for power calculation widely used in industry. The FLLs have a wide variety of applications such as power converters, grid synchronization, sensorless flux estimation, and control of motor drives. The nature of the FLL allows for it to be a potentially perfect calculation method for power calculation. The obtained results showcase the effectiveness of the proposed power calculation method. Keywords Keywords. Power measurement, addition theorems for trigonometry, DC component elimination, gain normalization, grid frequency synchronization, MAF filters, MATLAB/Simulink. Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021323 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Original research https://omeka.ibu.edu.ba/files/original/ade2f568548c50da88671751de1d9811.pdf 6570cefe0cdbb13adcd981ced48fd2a6 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Analysis of High School Graduate Data Using Database Analytics Tools Author Author Ezana Ćeman, Ajdin Salihović, Samed Jukić Abstract A summary of the resource. It can be confidently stated that access to education is one of the most prized possessions available to us today. Although there are underlying factors such as the discrepancies in the education being provided worldwide, it is imperative that data scientists and all those interested take advantage of the data publicly available to draw necessary insights into how to better the education sector in our respective countries. The purpose of this research is to showcase various analytical insights into the 2020 New York State (NYS) high school graduation rate data using various advanced database systems techniques, specifically using SQL. With these analyses, further studies and conclusions can be drawn for local governments to implement into their plans to increase the quality of the schooling system, to aim for equality for all without regard to cultural and ethnic background, and to find discrepancies within the current system.</div> <quillbot-extension-portal></quillbot-extension-portal> Keywords Keywords. Database, data analysis, graduate, high school, New York State, SQL Identifier An unambiguous reference to the resource within a given context ISSN 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021322 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English language Type The nature or genre of the resource Original research https://omeka.ibu.edu.ba/files/original/d576b84246d647befe028e10e6cd3d5f.pdf 1cf9dbb6a9979d6c63430c29348c1585 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource The Potential of Biomaterial-Based Solutions in Cancer Research and Treatment Author Author Hannah Boone Abstract A summary of the resource. Cancer is a very troubling disease due to its unique morphological characteristics, capacity for drug resistance, and immunosuppressive abilities. Traditional methods used both for research of cancer and its subsequent treatment have fallen short of being able to accurately understand and ultimately defeat cancer within the body. Biomaterials present a unique solution to many problems associated with cancer. The use of biomaterials in cancer cell modeling has promoted a better understanding of tumor microenvironments. Biomaterials can also serve as drug and adjuvant carriers that are more likely to reach their target cancer cells. Many biomaterials also have standalone antitumor properties, and can also help in modulating the immune response, triggering various immune cells to attack cancerous cells. Naturally derived biomaterials include polysaccharides, lipids, polypeptides, vitamin E derivatives, and even plant extracts like curcumin. Biomaterial-based cancer treatments tend to have a longerlasting and more dependable effect inside the body and can come in many different forms, from polymeric scaffolds to injectable nanoparticles. Keywords Keywords. Adjuvant therapy, biomaterials, cancer treatment, carrier, immunotherapy. Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021321 Publisher An entity responsible for making the resource available International Burch University Language A language of the resource English Type The nature or genre of the resource Literature review https://omeka.ibu.edu.ba/files/original/75d3d0af9ea8e10805ad5c3282bba357.pdf 7331ebb69ef6ccfd5bd7b7b6a4f1b3ca PDF Text Text Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 Effect of metals on antibiotic sensitivity, growth, and biofilm-forming capacity of B. subtilis subsp. spizizenii Selma Cifric1 1 International Burch University, Sarajevo, Bosnia and Herzegovina selma.cifric@stu.ibu.edu.ba Abstract – B. subtilis is normally considered a soil organism, it can be also found in the animal and human gastrointestinal tract. Bacillus subtilis subsp. spizizenii is a type of Bacillus subtilis complex. It shares up to 99% of homology with B. subtilis CU1, which can be represented as a probiotic strain. Metal compounds found in soil or used in agriculture can easily enter the food chain and end up in our gut. Gram-positive bacteria (e.g. Bacillus spp.) have good adsorptive capacity for metals due to high peptidoglycan and teichoic acid content in cell walls. There is some evidence that certain metals inside the intestine play an important role in influencing growth and functionality of specific probiotic strains. Some of them have inhibitory, while others have an activating effect on bacteria. This study revealed that metal compounds increased antibiotic susceptibility of B. subtilis subsp. spizizenii. Higher concentrations of metal solutions inhibited growth of tested bacteria. Culture did not show affinity to form biofilms before or after addition of metal solutions. Keywords – antibiotic susceptibility, biofilms, MIC, metals. 1. Introduction Various bacteria reside in the gut or arrive there by food consumption. A microbiome is the overall collection of the genetic material of all microorganisms that live on or inside our body or collection of the genetic material of microorganisms in a particular environment (e.g., in your gut). Bacteria within our gut have an important role in digesting food, modulating the immune system, providing protection against harmful microbes, and more. Multiple factors including genotype, antibiotics, mode of delivery, dietary habits, lifestyle, social interactions and environmental factors shape the gut microbiota to make everyone’s microbiome unique [1, 2, 3]. Metal compounds can cause alterations in the composition of the gut microbiota. Usually, decrease in richness as well as the diversity of gut microbiota, is observed after exposure to metals [4, 5]. Gram-positive bacteria (e.g. Bacillus spp.) have good adsorptive capacity for metals due to high peptidoglycan and teichoic acid content in cell walls, in contrast to Gram-negative bacteria [6]. The phylum Firmicutes found in colon is mostly composed of gram-positive species, such as Clostridium and Bacillus. There is some evidence that certain metals inside the intestine play an important role in influencing growth and functionality of specific probiotic strains. Some of them have inhibitory, while others have an activating effect on bacteria. It has been concluded that many effects of metals are strain-specific [7]. �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 Bacillus subtilis is a gram positive and catalase positive rods. It is spore-forming bacteria. Although normally considered a soil organism, it is also found in the animal and human gastrointestinal tract [8]. Bacillus subtilis subsp. spizizenii is a type of Bacillus subtilis complex. It shares up to 99% of homology with Bacillus subtilis CU1, which can be represented as a probiotic strain that can have specific outcomes on the immune system of the elderly [9, 10]. Probiotics are commensal bacteria in the gut that have a health beneficial effect on the host organism. However, there are still a few unresolved questions regarding the safety of certain Bacillus strains, which is the main reason for their still limited application as probiotics [11, 12]. Biofilms are communities of bacteria joined together by a sticky extracellular matrix. This extracellular matrix is also responsible for adherent biofilms to various surfaces. Probiotic bacteria in the gut also use biofilm attachment to bind to the mucosa layer of the intestine. Biofilm attachment improves their survival rate. Specifically, biofilms provide protection against antibiotics and enzymes [13, 14, 15]. Antibiotics are antimicrobial agents active against bacteria. Their mode of action can be bactericidal or bacteriostatic. Application of antibiotics influences intestinal microbiota. It affects growth, diversity and antibiotic resistance of bacteria. Since Bacillus subtilis are partially considered as probiotic bacteria, normally found in the human gastrointestinal tract, this study will show their antibiotic susceptibility in the presence of metal compounds that can end up in our gut via food intake [16, 17]. In this paper, the effect of metal compounds on biofilm forming capacity, bacterial growth, and changes in antibiotic sensitivity is examined. It is assumed that metal compounds would increase antibiotic sensitivity and suppress growth. 2. Methods 1. Cultivation of B. subtilis subsp. spizizenii strain Bacillus subtilis subsp. spizizenii (ATCC 6633) was cultivated on solid and liquid media (trypticase soy broth (TSB) broth, TSB agar). After overnight incubation at 37 C, the turbidity of bacterial density is adjusted to 0.5 McFarland standard, as such was used for further tests. 2. Determination of antibiotic susceptibility before the addition of metal supplements Bacteria is previously cultivated on TSB agar. Susceptibility to fifteen types of antibiotics will be performed using the standard Kirby-Bauer disk diffusion method [18]. Antibiotics (Liofilchem) are listed in Table 1 below. 3. Microbroth dilution method Microbroth dilution method will be used to determine the minimal dose of metal supplement necessary to inhibit the growth of bacteria (minimum inhibitory concentration - MIC). It is accomplished through the standardized broth microdilution assay procedure [19, 20]. 96-well microtiter plates were used. The metal salts were aseptically diluted in TSB broth in the following w/V solutions: 1%, 0.5%, 0.25%, 0.12%, 0.06%, 0.03%, 0.015%, 0.007%, 0.003%, 0.0018%, 0.0009%. The 96-well plate contained 100 ul of different concentrations of metal solutions (CuSO4, ZnSO4 x 7H2O, Fe(NO3)3, and Mg), 100 ul TSB broth, and 20 ul of B. subtilis subsp. spizizenii (0.5 McFarland standard). This test was done in triplets. The �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 purpose was to determine the exact concentration of each metal that inhibits bacterial growth. After overnight incubation at 37 C visible growth of bacteria is recorded and MICs have been determined. 4. Determination of biofilm forming capacity This test determines how different concentrations of CuSO4 - copper (II) sulfate pentahydrate (Sigma-Aldrich), ZnSO4 x 7H2O - zinc sulfate heptahydrate (Sigma-Aldrich), Fe(NO3)3 - iron (III) nitrate (Fisher Scientific), and magnesium complex (Twinlab - dietary supplement from local pharmacy) will facilitate the biofilm formation. This test will be performed using TCP method. The 96-well plate contained different concentrations of metals, TSB medium, and 20 ul of B. subtilis subsp. spizizenii (0.5 McFarland standard). The inoculated plate should be covered with a lid and incubated for 24 h at 37 C. After incubation the content of the plates is discarded and washed. Crystal violet assay is used as a method of indirect biofilm quantification. Each microtiter-plate well is stained with 120 ul of 0.1% crystal violet and set aside for 10 minutes. Microliter-plate is decanted again and washed with distilled water. The test is done in triplets [21, 22]. 5. Determination of antibiotic susceptibility after addition of metals Susceptibility to fifteen types of antibiotics (Table 1) after addition of metal solutions will be performed using the Kirby-Bauer disk diffusion method [18]. Table 1. List of fifteen antibiotic discs used for antibiotic susceptibility testing. Name of antibiotic Micrograms Abbreviation Cefoxitin 30 FOX30 Gentamicin 10 CN10 Oxacillin 1 OX1 Amoxicillin 10 AML10 Ceftazidime + clavulanic acid 40 CAL40 Ciprofloxacin 5 CIP5 Streptomycin 10 S10 Vancomycin 30 VA30 Erythromycin 15 E15 Ceftazidime 10 CAZ10 Amoxicillin-clavulanic acid 30 AUG30 Azithromycin 15 AZM15 Kanamycin 30 K30 Tetracycline 30 TE30 Ampicillin 2 AMP2 �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 3. Results After testing the effect of metal compounds on growth, antibiotic susceptibility, and biofilm forming capacity, the following results were obtained. Table 2 shows results obtained after performing antibiotic susceptibility test for B. subtilis subsp. spizizenii. It compares diameters of the inhibition zone (in millimeters), before and after addition of four different metal compounds. Table 2. Antibiotic susceptibility test for B. subtilis subsp. spizizenii. Diameter of the zone of inhibition is in millimeters. (* - partially bactericidal) B. spizizenii B. spizizenii + Mg B. spizizenii + ZnSO4 x 7H2O B. spizizenii + Fe(NO3)3 B. spizizenii + CuSO4 FOX30 25 28 27 28 24 CN10 20 22 21 20 21 OX1 15 18 18 17 15 AML1 0 9 12* 15* 14* 11 CAL40 0 0 0 0 0 CIP5 29 32 32 32 35 S10 19 20 18 19 19 VA30 18 21 20 20 20 E15 21 25 28 24 25 CAZ10 0 0 6 8 0 AGU30 21 23 25 24 22 AZM1 5 20 22 21 23 22 K30 22 24 24 23 24 TE30 26 31 29 30 27 AMP2 0 0 0 0 0 Since diameters of inhibition zones for fifteen antibiotics were measured manually, Figure 1 visualizes sizes of diameters and possible manual errors during the measurement process. �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 Figure 1. Antibiotic susceptibility to fifteen antibiotics measured by zone of inhibition (in millimeters). Results of microbroth dilution tests are presented in Table 3 and Figure 2. Table 3 shows how different concentrations of metal (w/V) solutions affect growth of B. subtilis subsp. spizizenii, while minimum inhibitory concentrations of metals are summarized in Figure 2. Table 3. Growth of B. subtilis subsp. spizizenii under different concentrations of metal solutions w/V solution 1% 0.5% 0.25% 0.12% 0.06% 0.03% 0.015% 0.007% 0.003% 0.0018% 0.0009% Mg Fe(NO3)3 CuSO4 ZnSO4 x 7H20 No growth No growth No growth No growth No growth No growth No growth No growth No growth Growth No growth No growth No growth Growth No growth No growth Growth Growth No growth No growth Growth Growth Growth No growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth Growth �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 Figure 2. Minimum inhibitory concentration (MIC) of metal compound for growth of B. subtilis subsp. spizizenii B. subtilis subsp. spizizenii did not show affinity to form biofilms before (visible to the naked eye) or after addition of metal solutions at any concentration (w/V). The limitation of this study might be that the optical density of each microplate was not measured using ELISA reader. 4. Discussion In order to test the antibiotic sensitivity and growth, for this particular experiment, different metals had been taken to test this effect. In this particular experiment, one of the metals that had been used was zinc sulfate, a specific solid that can have a colorless crystalline structure. In a historical approach, it is known that zinc could be found in soil where different plants are harvested, but in different areas there is something known as solid deficiency, where plants cannot develop properly and grow because of the lack of zinc. And in order for this to be corrected, people have experimented and found out that in order to correct this deficiency, zinc sulfate can be added to the soil in order to have the proper growth of different crops. Because these metals are used in order to grow crops, this may have a different effect when the crops are consumed as a food source. [23, 24, 25]. Copper (II) sulfate pentahydrate is most commonly described as an inorganic compound that could be found in copper in the form of salt. It is highly soluble in water. This type of salt has a usage as an additive in order to recover pentose sugars from the fronts of palm oils. It had been used as well to prove specific antimicrobial properties when working with specific types of bacteria, but most importantly here with Bacillus subtilis [26, 27]. Copper (II) sulfate is used as fungicide in agriculture, as an additive for fertilizers and food [28]. �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 Iron (III) nitrate, or in other words ferric nitrate, is a type of metal that can be used in many fields. This type of compound can be used to treat different sludges and wastewaters, it can be used to remove nitrogen from different plants and it can also be used in analytical chemistry [29, 30]. All three of metals aforementioned, zinc sulfate, copper (II) sulfate pentahydrate, and iron (III) nitrate, can be found in soil or are used in agriculture. In that way they can get into the food chain and enter the human gut. One of the most abundant minerals that are important for different metabolic processes in the human body is magnesium. It can be found in over 300 enzymes as a cofactor and it regulates different biochemical reactions that are processed in the human body. Usually, magnesium is provided as a type of dietary supplement, people consume it in order for their body to function properly, and different amounts of these minerals are given to people based on various factors [31]. For example, magnesium citrate helps with constipation, it acts as laxative, while magnesium aspartate is important for digestion of macronutrients [32]. B. subtilis subsp. spizizenii showed visible growth at 0.06% (w/V) magnesium solution (Table 3). Dietary supplement was used as a source of magnesium. No significant changes were recorded in antibiotic susceptibility tests in presence of Mg, except with amoxicillin. Addition of Mg solution slightly changed property of B. subtilis subsp. spizizenii. According to obtained results amoxicillin was partially bactericidal (a few colonies appeared within the inhibition zone) for tested bateria, in the presence of magnesium. Susceptibility to fifteen types of antibiotics (Table 1), before and after addition of metal solutions, will be performed using Kirby-Bauer disk diffusion method. This test showed that B. subtilis subsp. spizizenii is completely resistant to ampicillin (AMP2), as well as to ceftazidime+clavulanic acid (CAL40). Antibiotic sensitivity of B. subtilis subsp. spizizenii did not significantly change for the following antibiotics: gentamicin (CN10), streptomicin (S10), vancomycin (VA30), azithromycin (AZM15), kanamycin (K30), cefoxitin (FOX30), oxacillin (OX1), ciprofloxacin (CIP5). Change in diameter was less or equal to 3 mm. Note that diameters were measured manually, and manual errors (gross errors) should be taken into account. Difference in diameter of zone inhibition of erythromycin (E15) with addition of zinc sulfate heptahydrate and without metal solution is 7 mm. There was an increase in diameter size of the inhibition zone for tetracycline (TE30) and amoxicillin (AML10) in presence of magnesium, zinc sulfate heptahydrate, and iron (III) nitrate solutions, compared to diameters of inhibition zones before addition of metal compounds. Besides that, a few colonies of bacteria were observed within amoxicillin zones of inhibition. Amoxicillin was partially bactericidal for B. subtilis subsp. spizizenii, in presence of magnesium, zinc sulfate heptahydrate, and iron (III) nitrate solutions. �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 B. subtilis subsp. spizizenii without presence of metal solutions was resistant to ceftazidime (CAZ10). With addition of zinc sulfate heptahydrate, and iron (III) nitrate solutions, zones of inhibition were 6 and 8, respectively. Since B. subtilis subsp. spizizenii shares the biochemical similarities with Bacillus subtilis subsp. subtilis results for these two strains can be compared. There is up to 58 to 68% is the DNA relatedness between these two bacteria [10, 33, 34]. According to Silman et al. vancomycin showed great bactericidal effect for B. subtilis in general [35]. Our data shows that zones of inhibition obtained by vancomycin (VA30) are ~20 mm, while the largest zones of inhibition were recorded in presence of ciprofloxacin (CIP5) ranging from 32-35 mm in diameter (Figure 1). Sim et al. obtained similar results about CIP5 and TE30, where zones of inhibition were 32 and 31, respectively [36]. Bacterial growth was registered for all four metal compounds at different concentrations (Table 3). No bacterial growth was registered for Mg at the concentrations 0.1%, 0.5%, 0.25%, 0.12%, while bacterial growth occured at all other tested w/v solutions (Table 3). B. subtilis spizizenii growth occurred at all other w/v solutions of iron (III) nitrate except at the concentrations 0.1% and 0.5%. Growth of bacteria in the presence of copper (II) sulfate w/v solution occurred at concentrations 0.03-0.0009%. The lowest growth rate was observed in the presence of zinc sulfate heptahydrate solution, bacterial growth occurred only on concentrations 0.015-0.0009% (Table 3). The lowest concentration of chemical (drug, antimicrobial) that inhibits visible growth of microorganism (in this case bacteria) in overnight culture is known as minimum inhibitory concentration (MIC) [37]. After overnight incubation at 37 C MICs were recorded (Figure 2). Obtained MICs of metal solutions that inhibit growth of B. subtilis subsp. spizizenii are: magnesium 0.12%, iron (III) nitrate 0.50%, 0.06% copper (II) sulfate, 0.03% zinc sulphate heptahydrate. Considering that, growth of tested bacteria is slightly inhibited by iron (III) nitrate solution (bacteria is growing in presence of metal solution whose concentration is <0.50%), while it is tolerating much lower concentrations of zinc sulfate heptahydrate solution (<0.03%). For this experiment laboratory strain of B. subtilis subsp. spizizenii was used. This strain did not form biofilms at all. According to other studies, during domestication of laboratory strains of B. subtilis accumulation of mutation can occur which can lead to their inability to form well-structured biofilms. Compared to the laboratory strains, undomesticated strains of B. subtilis usually form rich and strong biofilms [38, 39]. 5. Conclusion B. subtilis complex is normally found in soil, however it is also found in the human gut as harmless bacteria. Further research is needed for its wider application on the probiotic market due to safety concerns. Metal traces can be found in soil, wastewaters, products used in agriculture, fungicides, etc. as �Journal of Natural Sciences and Engineering, Vol. 1, (2019) DOI number: 10.14706/JONSAE2019114 such they can easily enter our food chain and end up in the human gut. This study investigated how specific metal compounds influence growth, antibiotic susceptibility, and biofilm forming capacity of B. subtilis subsp. spizizenii. Based on the results that have been retrieved, we can conclude that higher concentrations of metal solutions inhibited growth of tested bacteria, while it showed good tolerance to majority of lower concentrations of metals. Generally, culture showed increased sensitivity against antibiotics after addition of metal solutions. B. subtilis subsp spizizenii used in this experiment was laboratory strain and was not able to form biofilms. No influence of metals was recorded there. 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Determination of minimum inhibitory concentrations. Journal of antimicrobial Chemotherapy, 48(suppl_1), 5-16. [38] Bate, A. R., Bonneau, R., & Eichenberger, P. (2016). Bacillus subtilis systems biology: applications of‐omics techniques to the study of endospore formation. The Bacterial Spore: from Molecules to Systems, 129-144. [39] McLoon, A. L., Guttenplan, S. B., Kearns, D. B., Kolter, R., & Losick, R. (2011). Tracing the domestication of a biofilm-forming bacterium. Journal of bacteriology, 193(8), 2027-2034. � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Effect of metals on antibiotic sensitivity, growth, and biofilm-forming capacity of B. subtilis subsp. spizizenii Author Author Selma Cifric Abstract A summary of the resource. B. subtilis is normally considered a soil organism, it can be also found in the animal and human gastrointestinal tract. Bacillus subtilis subsp. spizizenii is a type of Bacillus subtilis complex. It shares up to 99% of homology with B. subtilis CU1, which can be represented as a probiotic strain. Metal compounds found in soil or used in agriculture can easily enter the food chain and end up in our gut. Gram-positive bacteria (e.g. Bacillus spp.) have good adsorptive capacity for metals due to high peptidoglycan and teichoic acid content in cell walls. There is some evidence that certain metals inside the intestine play an important role in influencing growth and functionality of specific probiotic strains. Some of them have inhibitory, while others have an activating effect on bacteria. This study revealed that metal compounds increased antibiotic susceptibility of B. subtilis subsp. spizizenii. Higher concentrations of metal solutions inhibited growth of tested bacteria. Culture did not show affinity to form biofilms before or after addition of metal solutions Keywords Keywords. antibiotic susceptibility, biofilms, MIC, metals Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021323 https://omeka.ibu.edu.ba/files/original/837ee7ba8524552cc47c30a81ccd37ff.pdf fd1278d02233437664771934e94dee9c Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Journal of Natural Sciences and Engineering Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706 Publisher An entity responsible for making the resource available International Burch University Description An account of the resource Journal of Natural Sciences and Engineering (JONSAE) is a peer-reviewed, biannually published international journal focusing on empirical and theoretical research in all branches of Engineering and Natural Sciences. It is published on the behalf of Faculty of Engineering and Natural Sciences of International Burch University and aims to provide the best content regarding by publishing original research papers, review articles, special issues, feature articles, and book reviews. All manuscript submissions are subject to initial appraisal by the Editor, and, if found suitable for further consideration, to peer review by independent, anonymous referees. All peer review is double-blind and submission is online. The journal welcomes theoretical, applied, interdisciplinary and methodological work, with preference on empirical research, critical approach and problem-solving methods in manuscripts. Language A language of the resource English Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource INFLUENCE OF THE DISTRIBUTED GENERATION ON THE POWER QUALITY IN DISTRIBUTION NETWORK Author Author Alma Halilović, Lejla Mujanović, Jasna Hivziefendić Abstract A summary of the resource. The aim of this paper is to present and discuss the influence of distributed generation on power quality. Nowadays, interest in power quality has increased since it has become a very important issue in power system delivery. One of the major problems of ensuring a certain level of power quality are harmonics. The aim of this project is to investigate an impact of photovoltaic (PV) on harmonic voltage distortion (HD) in real MV distribution network. Different scenarios will be implemented where solar power plant is going to be modelled with high variability of load and generation to see their effects on the systems power quality (PQ). Those scenarios are when PV is disconnected from the grid and PVs are connected with 2 different powers. Results presented below showed that PV improves power quality of the system, because their inverters are source of harmonics and they increase HD. However, that impact is not very significant and harmonic limits are not violated. A load flow analysis is done for the model of test system 110/35/10kV in which a distributed generator is added, that is on-grid or off-grid. The network modelling and simulation is done in DIgSILENT PowerFactory software. Keywords Keywords. DIgSILENT, power system harmonics, PVs, power quality, harmonic distortion. Identifier An unambiguous reference to the resource within a given context 2637-2835 DOI Digital object identifier 10.14706/JONSAE2021322