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Almir Ekic, Bennett Strombeck, Di Wu, G. Ji

While the increasing penetration of renewable energy resources into the electric power grid improves energy efficiency and reduces greenhouse gas emissions, it may drive the grid towards weak power grid conditions, under which grid stability issues may affect the operation of inverter-based renewable generators. The short-circuit ratio (SCR) with some modifications has been used to analyze power grid strength. However, the existing SCR-based methods for grid strength assessment neglect the impact of the interactions between shunt capacitors interconnected through the power network, which may cause over-optimistic results of grid strength assessment. To account for the impact, a novel method for grid strength assessment is proposed in this paper by theoretical analysis of how the interconnected capacitors affect static voltage stability. The efficacy of the proposed method is demonstrated through numerical simulation case studies on the IEEE 39-bus system.

Long Chen, Almir Ekic, Di Wu

The electric power grid is undergoing significant changes in the mix of generation source types. The increasing penetration of renewable energy resources (RERs), such as wind and solar, is improving energy efficiency, but meanwhile it is also challenging grid planners and operators to maintain reliable electricity services. The high penetration of RERs may drive the power grid toward weak grid conditions, which may cause grid stability and reliability issues. One of ways to address these issues is to select appropriate points of interconnection for integrating RERs into power grids. In previous works, grid stability analysis and grid reliability assessment are evaluated separately for selecting the points of interconnection. This paper presents an integrated method for selecting such points by coordinating grid strength assessment and grid reliability evaluation as well as investment cost. The efficacy of the proposed method is demonstrated on the IEEE reliability test system.

S. Sefic, Aida Kasumović, Ines Matoc, Tarik Halimić, Bahrija Voloder, L. Muhamedagić, Seldjana Catovic Delic, Irena Sesar

Introduction: Monitoring and diagnosing glaucoma until 2017 included funduscopy, IOP measurements, gonioscopy, pachymetry, as well as visual field tests, optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). Radial peripapillary capillaries (RPC) can be observed by fluorescein angiography, as well as histologically - superficial and deep capillary layer. Aim: To correlate density of radial peripapillary capillary network (RPC) and retinal nerve fiber layer (RNFL) thickness in eight peripapillary segments in patients with a primary open angle glaucoma (POAG) which have the disease under 10 years of duration, over 10 years of duration and in a group of healthy patients. Methods: This is a cross-sectional review which included three groups of patients: POAG patients under 10 years of disease duration, over 10 years of disease duration and control group of patients. The study is performed on the commercial optical coherence tomography angiography system (AngioVue, Avanti RTVue-XR, Optovue, CA). Sectoral RPC density values, RPC maps and RNFL thickness were analyzed in three groups of patients, data was compared and correlation between parameters was examined. Results: Mean RPC Density values in both superior segments (S1, S2) were significantly lower in patients with glaucoma over 10 years of disease duration compared to patients with glaucoma under 10 years of disease duration (p<0.05). Statistically significant positive correlation was established between RNFL thickness and RPC density in all eight peripapillary segments. Conclusion: Analysis of radial peripapillary capillary network density on optical coherence tomography angiography may provide an earliest functional sign of progressive optic nerve disease and new insights into the pathophysiology of glaucomatous damage.

M. Hukić, H. Avdihodžić, I. Kurolt, A. Markotić, J. Hanjalić, L. Kapur-Pojskič, Irma Mahmuljin, M. Avdić et al.

Aim Phlebotominae sandflies are primary vectors of phleboviruses, causing the sandfly fever disease. The aim of this study was to detect and report the presence of flaviviruses in Phlebotominae sandflies captured in Bosnia and Herzegovina. Methods After a microscopic and morphometric analysis, the final identification of collected Phlebotomus specimens was confirmed by PCR, using a hemi-nested polymerase chain reaction on extracted and reversely transcribed RNA. Results We obtained a 155 nt long fragment of the viral non-structural protein 5 (NS5) gene (GenBank accession no. MN090154). The acquired nucleotide sequence, provisionally named as Drežnica, showed a maximum of 70-80% identity in 70-88% (110-137 nucleotides) of the query coverage with several Anopheles, Sabethes, Calbertado and Culex flaviviruses. Maximum likelihood phylogenetic analysis showed that the new flavivirus Drežnica clusters together with the flavivirus isolated from Culiseta annulata mosquitos. Conclusion We report the presence of flavivirus in Phlebotominae sandflies, captured in Drežnica, Herzegovina for the first time. The next phase of research will be directed towards virus cultivation, obtaining a longer or complete virus sequence and clarifying the medical and epidemiological importance of the Drežnica virus.

Gorana Ahmetović-Karić, elma catovic-baralija, A. Sofo-Hafizović

Aim To present characteristics of collecting autologous peripheral blood stem cells over a one-year period with an emphasis on efficiency and safety. Methods A retrograde analysis of 24 leukapheresis in 20 adult patients with malignant haematological diseases in the Blood Transfusion Institute of the Federation of Bosnia and Herzegovina in Sarajevo, was done. Cell separators Amicus and Spectra Optia were used for collection procedures. Results The patient's age ranged from 27 to 65 years. Target cells were collected in one procedure in sixteen patients, while in four patients they were collected in two procedures. The mean CD34+ collection efficiency was 57.7%. The median number of CD34+ cells and percentage of CD34+ cells in the products were 5.52x10e6/kg (range 3.28-9.00) and 1.57% (range 0.96-2.91). A strong positive correlation was found between the number of CD34+ cells in peripheral blood on the apheresis day and the amount of CD34+ cells collected in the products (rs =0.73). A total of 95% of patients collected the amount of ≥3x10e6/kg and 55% of ≥5x10e6/kg CD34+ cells for a single transplant. A decrease in platelet count, haemoglobin and haematocrit values after the procedure was not significant. Potassium decrease showed statistical significance (p<0.000). Adverse events occurred during one procedure (4.2%). Conclusion A low number of adverse events and good collection efficiency with adequate patient monitoring, indicate that leukapheresis is a safe procedure that is successfully used in the autologous transplantation process in the treatment of malignant haematological diseases.

Piero Amodio, M. Boeckle, S. Jelbert, L. Ostojić, Nicola S. Clayton

– Eurasian jays ( Garrulus glandarius ) do not habitually use tools, yet they can be trained to solve object-dropping tasks, i.e., to insert a tool into an apparatus to release a food reward. Previous research suggests that these jays can learn a preference toward functional tools – objects allowing them to obtain a food reward placed inside an apparatus – according to their density (Cheke et al., 2011). However, it is not yet known whether they can also select functional tools (tool selectivity) according to other physical properties such as size and shape and use different kinds of tools to solve a similar task. Here we conducted three object-dropping experiments aimed at exploring these abilities in Eurasian jays. In Experiment 1, jays tended to select large stones as tools irrespective of the diameter of the apparatus. However, jays progressively developed a preference for the small tool, which was functional with both the wide and the narrow apparatuses. In Experiment 2, only vertically oriented long stones could fit into the narrow apparatus, whereas both long and round stones were functional with the wide apparatus. Jays showed a preference for the long stone and, with the narrow apparatus, tended to achieve the correct manipulation after one or more unsuccessful attempts. In Experiment 3, jays were able to use sticks and adopt a novel technique on the same object-dropping apparatus, thus providing the first evidence that Eurasian jays can use sticks as tools. Taken together, these results do not support the notion that tool selectivity abilities can be found in Eurasian jays but nonetheless show that these corvids can use different kinds of tools to solve similar tasks.

Aim To determine the degree of accuracy in determining the sex of the skull based on classical morphometric analysis of the mastoid process. Morphometric analysis excluded a subjective approach expressed in osteoscopic analysis. Methods The study was conducted on a sample of 100 macerated skulls of known gender and age from the second half of the 20th century, including the Bosnian population. Of the 100 skulls, 50 (50%) were male and 50 (50%) were female. Male skulls were on average 60 (47-71) years old and female 57 (43-76) years old. At each mastoid process, 3 measurements were made: mastoid length, mastoid width (medio-lateral diameter) ML) and anteroposterior diameter (AP) of the mastoid process. Results Using the univariate method, we found a significant difference between length, width, AP diameter and size of mastoid processes as well as between gender (p <0.05). Multivariate binary logistic regression showed statistically significant differences in AP diameter of the mastoid process (p<0.05). Conclusion The created model "P" ("P"=exp [X]/1+exp [X]) for sex determination based on mastoid process showed sensitivity of 82% correct prediction for female skulls and 65% accurate prediction for male skulls. This discourse with respect of population standards grants most effective anthropological proof and as such may be suggested for forensic expertise based on human skull.

D. Hadžić, F. Skokić, S. Brkić, Amina Saračević, Delila Softić, D. Softić

Aim Steady progress in intensive treatment worldwide has increased the survival of immature neonates, but with multiple invasive procedures, which have increased the risk of infection, thus the bacterial resistance to antibiotics. The aim of this study was to analyse the epidemiology of multidrug resistance pathogens as causative agents of neonatal sepsis in the neonatal intensive care unit. Methods A retrospective cohort study conducted at the Intensive care unit of the Paediatric Clinic of Tuzla over a three-year period (2016-2018) analysed epidemiology of neonatal sepsis caused by multidrug resistance pathogens. Statistical analysis applied standard methods, and the research was approved by the Ethics Committee of the institution. Results Of the total of 921 treated neonates, multidrug resistance (MDR) pathogens among causative agents of neonatal sepsis were found in 22 neonates (2.38%) with no gender difference. Prematurity and low birth weight were confirmed as the most significant risk factors. From the maternal risk factors a significant difference was found in the first birth and in vitro fertilization. Clinically, MDR sepsis manifested frequently as late onset sepsis, with longer hospital stay and higher mortality. The findings of leukopenia, thrombocytopenia and coagulation disorders were significant. Gram negative bacteria were frequently isolated, in particular Acinetobacter, which showed the greatest resistance to antibiotics. Conclusion Neonatal MDR sepsis is a threat to life, it complicates the treatment, increases costs and mortality. Outcomes can be improved by preventive strategies, earlier and more accurate diagnosis and rational use of antibiotics.

At the end of 2019 the world became aware of the existence of a new virus stemming from the Coronaviridae family and causing a specific disease – COVID-19. In less than three months, the virus and its consequences, developed from being a local public health problem in China to a daunting global problem we all had to face. On March 11, 2020 the World Health Organization (WHO) declared a pandemic of COVID-19. On the international scale, even in Bosnia and Herzegovina (BiH), the response of the professionals and scientists has been rapid, although not always consistently efficient enough. Despite the selfless cooperation of scientists and practitioners worldwide, countries with developed economies, good public health and a strong scientific system have had the advantage in the fight against the disease over developing countries. Despite the fact that by these criteria BiH is not one of the most resilient countries, so far, its response to the pandemic has seemed to be satisfactory. The Academy of Sciences and Arts of Bosnia and Herzegovina (ANUBiH) was one of the first institutions of the science system to respond to the pandemic. On the initiative and under the leadership of academician Mirsada Hukić, on March 22, 2020 the development of the project "Epidemic Location Intelligence System (ELIS)" and its Geoportal began on a voluntary basis, with the task of permanently monitoring the spread of COVID-19. Theoretical and professional parts of the project in the areas of medicine, public health and informatics were completed by April 2, 2020. Thanks to the support to the project by the Chairman of the Presidency of Bosnia and Herzegovina, Mr. Šefik Džaferović, the expert system received additional hardware support and was filled in time with data from across the country. This enabled the system to become operational as early as on April 8, 2020. The results of all these efforts are visible in this publication. Initially, the ELIS project was important for the epidemiological and public health area. The abundance of collected data and obtained virus samples enabled the extension of the project idea to the sequencing of viruses found in BiH and their typology. The transition of research to the clinical aspects of COVID-19 is the next phase in the development of the ELIS project. ANUBiH has already started the work on examining the economic and pedagogical consequences of COVID-19 in order to look at this medical phenomenon in the broadest possible context. All the results of ANUBiH in response to the epidemic challenges of COVID-19 are achieved due to the synergistic action of numerous individuals and institutions in different fields of science and public health in cooperation with government. Therefore, I believe that the ELIS project has shown the way to go in solving the burning problems of our society which we will encounter in the future.

Aim The damage caused by the COVID-19 pandemic has made the prevention of its further spread at the top of the list of priorities of many governments and state institutions responsible for health and civil protection around the world. This prevention implies an effective system of epidemiological surveillance and the application of timely and effective control measures. This research focuses on the application of techniques for modelling and geovisualization of epidemic data with the aim of simple and fast communication of analytical results via geoportal. Methods The paper describes the approach applied through the project of establishing the epidemiological location-intelligence system for monitoring the effectiveness of control measures in preventing the spread of COVID-19 in Bosnia and Herzegovina. Results Epidemic data were processed and the results related to spatio-temporal analysis of the infection spread were presented by compartmental epidemic model, reproduction number R, epi-curve diagrams as well as choropleth maps for different levels of administrative units. Geovisualization of epidemic data enabled the release of numerous information from described models and indicators, providing easier visual communication of the spread of the disease and better recognition of its trend. Conclusion The approach involves the simultaneous application of epidemic models and epidemic data geovisualization, which allows a simple and rapid evaluation of the epidemic situation and the effects of control measures. This contributes to more informative decision-making related to control measures by suggesting their selective application at the local level.

H. Tahirovič, Brigitte Fuchs

This article describes the life and medical activities of Jadwiga Olszewska (1855-1932) in Serbia from 1895-1899, AustroHungarian (AH)-occupied and annexed Bosnia and Herzegovina (BH) from 1899-1918, and the newly founded Kingdom of Yugoslavia, from 1919-1932. In summer 1899, Olszewska replaced Teodora Krajewska as an AH official female physician in Tuzla. Born in Congress Poland, Olszewska had enrolled in 1873 in the medical courses for women in St. Petersburg but had left Russia in 1880 to study medicine in France. She had lived as a student and single parent in Paris since 1883, and she was awarded her Doctorate in Medicine from the University of Paris in 1894. She could not practice medicine in Russian-occupied Poland because of her French diploma, and she could not practice in most Western countries due to her gender. Therefore, she decided to move to Serbia, where she worked as an assistant physician in the district hospitals of Loznica (1895-1897?) and Požarevac (1897-1899). Driven by the need for a higher income to fund her son's education, she engaged her network of Polish compatriots and procured the position of an AH official female physician of Tuzla in 1899, where she performed her duties in an exemplary manner. After the breakdown of the Austro-Hungarian Empire (AHE) in 1918, Olszewska remained in Tuzla and retired as a Yugoslav official physician in 1923. When she died in Tuzla in 1932, local colleagues had to arrange for a proper funeral because Olszewska did not leave any savings due to her insufficient pension. Olszewska's grave never received a tombstone, and it is untraceable today. CONCLUSION: Jadwiga Olszewska (1855-1932) was a woman pioneer of medicine from Poland, who practiced her profession first as an assistant physician in Serbia (1895-1899) and then as an AH and Yugoslavian official female doctor in Tuzla, BH (1899-1923).

In contrast to classical appendectomy where the appendiceal stump is secured by a single or double ligature, in laparoscopic appendectomy various ways of securing the stump are mentioned. Each of these methods has advantages and disadvantages. Since different possibilities exist for closing the stump, it is very important to find the optimum method for closure of the appendiceal stump, bearing in mind their simplicity, biocompatibility and price. The aim of this review article has been to present the problem of securing the base of the appendix during laparoscopic appendectomy.

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