Introduction: Certain methodological principles should be inexcusably followed when designing clinical or observational research to avoid bias and presentation of results that do not reflect the truth about the phenomenon that is the object of the study. Aim: The aim of this study was to compare the methodological quality of clinical trials and observational studies published in medical journals from ex-Yugoslav countries indexed in Pubmed/MEDLINE. Methods: Clinical studies published in medical journals of ex-Yugoslav countries were retrieved from the Pubmed/MEDLINE database, and the sample for analysis was randomly chosen from the retrieved publications. The rate of the most common errors in the design of clinical/observational studies was established by a careful reading of the sampled publications and their checking against predefined criteria. Results: The studies published in two countries that are now member states of the European Union (Slovenia and Croatia) have significantly higher citation rates, impact factor, and methodological quality scores than studies from other ex-Yugoslav countries. While publications from Croatia show clear improvement trend throughout the last two decades, which is visible also in the last 10 years in Slovenia and Bosnia and Herzegovina, quality of clinical research published in journals from Serbia was stagnating in the same period. Conclusions: There are significant differences in methodological quality and scientometric characteristics of clinical research published in medical journals of ex-Yugoslav countries that could be mitigated by more intensive training of clinical researchers in statistics and research design, as well as by more rigorous editorial practices.

Glucose is a main source of energy in human body and its regulation is controlled by a biological mechanism with organ/cell interactions that are related to glucose-insulin dynamics. This paper presents the model of physiological behaviors of glucose-insulin regulatory mechanism. This model allows investigation of blood glucose dynamics dependency on food intake. The model presented in this paper discusses several parameters within this complex system.

Introduction: Early correction of congenital ptosis may be indicated due to a risk of amblyopia or because of an abnormal head tilt. One of the main problems, of planning ptosis surgery in very young children, is the inability to measure the levator function. Aim: The aim of the article was to analyze the early correction of congenital myogenic ptosis. Methods: This was a retrospective, interventional, case series study, conducted on 12 eyes of 12 patients with unilateral, mild to moderate, congenital myogenic ptosis. Surgical correction of ptosis was performed by transconjunctival levator muscle plication. Pre- and postoperative measurements of the upper lid margin to central corneal reflex (MRD1) and upper lid skin crease height (UEC) were obtained, as well as the presence or absence of a reaction to topically applied phenylephrine 2.5% solution. Results: The mean age of the patients was 29.83 months (range 14-45 months). A negative phenylephrine test was noted in only 3 (25%) of cases. Equalization of upper lid height was achieved in 6 (50%), and a hypocorrection of up to 1 mm was noted in 4 (33%) of patients. There was only 1 hypercorrection of 1 mm, noted in the first postoperative month. In one case of hypocorrection of 2 mm, the height of the lid dropped between the 1 and 3 months follow up. Subsequent revision surgery was performed, with a good outcome. With regard to the upper lid skin crease height (UEC), the mean preoperative difference in relation to the contralateral (non-operated) lid, was 2.16 mm, whereas the average postoperative or final difference was 0.41 mm. Conclusion: Correction of myogenic ptosis in small children, using transconjunctival levator plication, in whom levator function cannot be measured, may have a satisfactory postoperative outcome.

Nowadays, high voltage circuit breaker (CB) simulations are mostly based on Computational Fluid Dynamics (CFD) models. Such simulations require significant computer resources. An alternative approach is to use enthalpy flow models, which do not use space discretization of the interrupter unit chambers and valves. Gas flow is calculated based on state of gas in adjacent chambers and valve settings. However, the valve shape has significant influence on the effective flow cross section between chambers. Therefore, in order to ensure correct simulation results, it is necessary to determine the correct values of discharge coefficients for all valves in the interrupter unit of a circuit breaker. In this paper, the discharge coefficients were determined by combining a series of CFD and enthalpy flow simulations for each valve in the interrupter unit. After that, discharge coefficients are used as input for further simulations based on the enthalpy flow model. This way, benefits from both models are combined: more precise gas flow calculation and faster simulations. The proposed novel approach is validated in a high-power laboratory by pressure measurements on a 420 kV 63 kA self-blast circuit breaker.

Introduction: Although during undergraduate study students have a high opinion of family medicine and often praise it, during postgraduate studies they show little interest in this medical specialty. Aim: The study aimed to examine the interest of public medical school students in family medicine as a career choice, to establish whether it changed during the study and if there was a difference in that regard among students studying at medical schools in Bosnia and Herzegovina. Hypotheses: students’ attitudes change with learning about the way a family doctor works. Methods: Descriptive cross-sectional survey. This manuscript presents a nationwide survey (63% response rate) of public medical school students in Bosnia and Herzegovina regarding their likelihood of selecting Family Medicine as a specialty. An anonymous questionnaire was distributed to all medical students on all six state universities in Bosnia and Herzegovina. Data basis of all doctors who have completed specialization programs were taken from ministries of health. Results: In the period from 01/01/08 to 12/31/18, only 8.4% of all completed specializations were family medicine doctors in Bosnia and Herzegovina. Interest in family medicine, as a future career, was shown by 31% of medical students, of which over 75% were female students. The largest interest in family medicine was shown by the sixth-year medical students, stating their extensive knowledge of medicine as a reason. Conclusion: Students’ interest in FM specialization is changing through the years of study. Unfortunately, it is not only the lack of interest, that is the cause of the small number of family medical specialities among students but also poor health policy, which should be subjected to actual reform.

Colorectal cancer (CRC) is a common malignancy with a high mortality rate worldwide. It is a complex, multifactorial disease that is strongly impacted by both hereditary and environmental factors. The role of microbes (e.g., viruses) in the pathogenesis of CRC is poorly understood. In the current study, we explored the status of high-risk human papillomaviruses (HPV) and Epstein–Barr virus (EBV) in a well-defined CRC cohort using immunohistochemistry and polymerase chain reaction assays. Our data showed that high-risk HPVs were common (~80%) and EBV had a low presence (14–25%) in the CRC samples. The most common high-risk HPVs are HPV16, 31, 18, 51, 52 and 45 genotypes. The co-presence of high-risk HPV and EBV was observed in ~16% of the sample population without any significant association with the clinicopathological variables. We conclude that high-risk HPVs are very prevalent in CRC samples while EBV positivity is relatively low. The co-expression of the two viruses was observed in a minority of cases and without any correlation with the studied parameters. Further studies are necessary to confirm the clinical relevance and potential therapeutic (preventive) effects of the observations reported herein.

Background: Smoking is one of the most significant modifiable exosomes risk factors for rheumatoid arthritis (RA) (1). Studies suggest that 25-30% of people with RA in Denmark smoke (2). This is almost twice as many as in the background population in Denmark. People with RA have a significant increased risk of severe comorbidity including cardiovascular disease. In addition, there are indications that smokers with RA have a poorer effect of the medical inflammatory treatment compared to non-smokers, and consequently more difficult to achieve remission of the disease activity (3). Tobacco addiction is complex and can be a challenge in smoking cessation. In addition to physiological dependence, habits and social and environmental factors may influence addiction. Tobacco smoking is associated with an addiction to nicotine and it is unexplored how this addiction appears in people with RA. Objectives: The aim of this study was to examine from the patient’s perspective how tobacco addiction appears in people with rheumatoid arthritis. Methods: We conducted a qualitative study based on a hermeneutics approach. People with RA who previously had participated in a randomized controlled study (4) about smoking cessation conducted at the Center for Rheumatology and Spine Diseases at Rigshospitalet, Denmark were recruited for semi-structured interviews. Results: In total, 12 people with RA (50% female) were included in the study. The median age was 62 years and median RA disease duration was 12 years. The degree of physical dependence measured by Fagerstroms Test for Nicotine dependence (FTND) was on average: 4.9 (score: 0-10, 0=nonphysical dependence). Three categories of how tobacco addiction appeared emerged during the analysis: 1) It develops into ingrown habits referring to the fact that smoking already in adolescence contributes to the development of specific physical, mental and social smoking behavior. Not all individuals considered themselves addicted to nicotine as they did not necessarily connect the nicotine to the ingrown habits. 2) The body craves for nicotine referring to nicotine proved calming, while a lacking or insufficient dose caused withdrawal symptoms. Furthermore, smoking became a habit where a craving for smoking occurred in certain situations. 3) Ambivalence – for and against referring to the physical dependence and smoking habits making a smoking cessation difficult. Dependency to nicotine and challenges to quit smoking led to a feeling of ambivalence and a lack of control. Conclusion: Tobacco addiction appeared as a physical dependence and a habit, which, during a smoking cessation, led to ambivalent feelings. Therefore, based on this study, there is still a need for health professionals to talk to patients about smoking. But also, a need to articulate the complexity of addiction in order to support for smoking cessations. Information should be strengthened in the clinical practice in relation to nicotine’s implication in tobacco addiction as well as the consequences of tobacco smoking for individuals with RA. References: [1]Scott DL, Wolfe F, Huizinga TW. Lancet. 2010 ### [2]Loppenthin K, Esbensen BA, Jennum P, Ostergaard M, Tolver A, Thomsen T, et al. Clin Rheumatol. 2015. ### [3]Roelsgaard IK, Ikdahl E, Rollefstad S, Wibetoe G, Esbensen BA, Kitas GD, et al. Rheumatology (Oxford). 2019. ### [4]Roelsgaard IK, Thomsen T, Ostergaard M, Christensen R, Hetland ML, Jacobsen S, et al. Trials. 2017;18(1):570.### Disclosure of Interests: None declared

Introduction: Hyperuricemia is an independent risk factor for the development of many diseases. Aim: The aim of this paper is to compare the effects of allopurinol and febuxostat on the values of triglycerides and uric acid in hyperuricemic patients. Methods: This was a pharmacological-clinical retrospective-prospective study. The research sample comprised 50 examinees of both genders and different ages who were undergoing allopurinol (100 mg/day) or febuxostat (80 mg/day) therapy. Statistical Product and Service Solutions (SPSS) Software and Microsoft Excel were used for statistical analysis. Results: Examinees who were treated with allopurinol had a statistically significant decrease in uric acid concentrations (by 126.28 ± 20.36 μmol/l) at the end of the observation compared to the initial values (p = 0.006). Examinees who were treated with febuxostat had a statistically significant decrease in uric acid concentrations (by 252.80 ± 94.17 μmol/l) at the end of the observation compared to the initial values (p = 0.001). The initial value of triglycerides was 1.58 ± 0.64 mmol/l in allopurinol-treated examinees, and 1.60 ± 0.52 mmol/l in febuxostat-treated examinees. After three and six months of allopurinol use, there was a statistically significant increase in triglyceride values (p = 0.046 and p = 0.042, respectively). A statistically significant decrease in triglyceride values (by 0.16 ± 0.10 mmol/l) was noted after three months of febuxostat use (p = 0.012). Conclusion: The results of this research confirmed the previous findings and pointed out the positive pharmacological effects of allopurinol and febuxostat.

A questionnaire on biomarker testing previously used in central European countries was extended and distributed in Western and Central European countries to the pathologists participating at the Pulmonary Pathology Society meeting 26–28 June 2019 in Dubrovnik, Croatia. Each country was represented by one responder. For recent biomarkers the availability and reimbursement of diagnoses of molecular alterations in non-small cell lung carcinoma varies widely between different, also western European, countries. Reimbursement of such assessments varies widely between unavailability and payments by the health care system or even pharmaceutical companies. The support for testing from alternative sources, such as the pharmaceutical industry, is no doubt partly compensating for the lack of public health system support, but it is not a viable or long‐term solution. Ideally, a structured access to testing and reimbursement should be the aim in order to provide patients with appropriate therapeutic options. As biomarker enabled therapies deliver a 50% better probability of outcome success, improved and unbiased reimbursement remains a major challenge for the future.

This paper presents an off-body indoor propagation channel model. The model is based on a Friis transmission equation to which it adds the orientation-dependent body shadowing loss by adopting a basic model derived from a cosine function. Furthermore, the developed propagation model accounts for human body dynamics and different material reflections coefficients, both implemented using a random variables with uniform distribution. Created model was evaluated against a set of measurements conducted in the indoor environment at mmWave frequency (60 GHz) gathered from the literature, showing a good fit. The difference between the slopes of the proposed model and measurements is less than 6%.

This paper investigates the influence of user dynamics on small-scale fading characteristics in off-body channels. A statistical channel model employing a mobility model for wearable antennas on dynamic users is presented. The model is used to analyze the effects of both user’s linear forward motion and periodic wearable antenna displacement due to changes in posture, for walking and running. The time-variant Doppler shift exhibited by signals arriving from different directions is considered for wearable antennas on the chest, wrist and lower leg. A strong influence of the on-body placement is observed, with antennas on the arms and legs yielding up to a 2.2 times higher maximum Doppler frequency than with the antenna on the torso. Furthermore, the small-scale fading dynamics for these antennas vary considerably during the motion cycle, where one can distinguish between slow and fast phases. The latter is found to yield up to 4 times as high root-mean-square level-crossing rates than the former, in the case of the antenna on the lower leg. These findings imply an important effect of the periodic antenna displacement on fading dynamics in off-body channels, which is typically neglected in literature.

This paper presents the results of development of Artificial Neural Networks (ANNs) for prediction of medical device performance based on conformity assessment data. Conformity assessment data of medical devices was obtained from periodical inspections conducted by ISO 17020 accredited laboratory during 2015–2019 period. For the development of ANNs, 1738 samples of conformity assessment of infusion and perfusor pumps was used. Out of the overall number of samples, 1391 (80%) of them were used during system development and 346 (20%) samples were used for subsequent validation of system performance. During system development, the impact on overall system accuracy of different number of neurons in hidden layer and the activation functions was tested. Also, two neural network architectures were tested: feedforward and feedback. The results show that feedforward neural network architecture with 10 neurons in single hidden layer has the best performance. The overall accuracy of that neural network is 98.06% for performance prediction of perfusor pumps and 98.83% for performance prediction of infusion pumps. The recurrent neural network resulted in accuracy of 98.41% for both infusion pumps and perfusor pumps. The results show that conformity assessment data obtained through yearly inspections of medical devices can successfully be used for prediction of performance of single medical device. This is very important in increasing the safety and accuracy of diagnosis and treatment of patients.