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V. Mrzljak, J. Kudláček, Đerzija Begić-Hajdarević, J. Musulin

In this paper is presented an analysis of gland seals operation and their influence on the performance of low power steam turbine with two cylinders and steam reheating, which can be used in marine applications. Performed analysis presents a comparison of steam turbine main operating parameters when gland seals operation is neglected (as usual in the most of the literature) and when steam mass flow rates leaked through all gland seals are taken into consideration. Steam mass flow rate leakage through all gland seals reduces produced power of the whole turbine and both of its cylinders. Operation of gland seal mounted at the inlet in the first cylinder of any steam turbine (cylinder which operates with the steam of the highest pressure) has the most notable influence on the reduction of the whole turbine produced power. Gland seal mounted at the outlet of the last turbine cylinder (cylinder which operates with the steam of the lowest pressure) did not have any influence on the reduction of steam turbine produced power. In any detail analysis of a steam turbine (especially the complex turbine with multiple cylinders), gland seals operation should be considered due to their notable influence on the turbine performance.

L. Gren, V. Malmborg, N. Jacobsen, P. Shukla, K. M. Bendtsen, A. Eriksson, Y. Essig, A. Krais et al.

Renewable diesel fuels have the potential to reduce net CO2 emissions, and simultaneously decrease particulate matter (PM) emissions. This study characterized engine-out PM emissions and PM-induced reactive oxygen species (ROS) formation potential. Emissions from a modern heavy-duty diesel engine without external aftertreatment devices, and fueled with petroleum diesel, hydrotreated vegetable oil (HVO) or rapeseed methyl ester (RME) biodiesel were studied. Exhaust gas recirculation (EGR) allowed us to probe the effect of air intake O2 concentration, and thereby combustion temperature, on emissions and ROS formation potential. An increasing level of EGR (decreasing O2 concentration) resulted in a general increase of equivalent black carbon (eBC) emissions and decrease of NOx emissions. At a medium level of EGR (13% intake O2), eBC emissions were reduced for HVO and RME by 30 and 54% respectively compared to petroleum diesel. In general, substantially lower emissions of polycyclic aromatic hydrocarbons (PAHs), including nitro and oxy-PAHs, were observed for RME compared to both HVO and diesel. At low-temperature combustion (LTC, O2 < 10%), CO and hydrocarbon gas emissions increased and an increased fraction of refractory organic carbon and PAHs were found in the particle phase. These altered soot properties have implications for the design of aftertreatment systems and diesel PM measurements with optical techniques. The ROS formation potential per mass of particles increased with increasing engine O2 concentration intake. We hypothesize that this is because soot surface properties evolve with the combustion temperature and become more active as the soot matures into refractory BC, and secondly as the soot surface becomes altered by surface oxidation. At 13% intake O2, the ROS-producing ability was high and of similar magnitude per mass for all fuels. When normalizing by energy output, the lowered emissions for the renewable fuels led to a reduced ROS formation potential.

Nenad Miseljić, Sead Ibrahimovic

Introduction: The health implications of Caesarean section are a significant factor in evaluating the use of Caesarean section as a method of completing childbirth. The increased rate of Cesarean section augmenting in a statistical way the health implications of the use of Cesarean section as a way of operative technique of childbirth finalization. Aim: To investigate the incidence of health implications on mother and child after Cesarian section in comparison to vaginal delivery. Methods: In our study, which was conducted as a retrospective-prospective and targeted study, the observed research period is from 2007 to 2019. The data sources are: medical histories, birth protocols and neonatal medical histories. Group A: represents the number of surveyed patients with a Cesarean section in a one-year period (2018) in General Hospital „Prim.dr A. Nakaš“. Group B: represents a control group of the same number of patients born by Caesarean section in 2007 in General Hospital „Prim.dr A.Nakaš“ with all parameters and variables detected in the research group. Evaluation of the examinee’s findings includes: anamnestic data, sonographic data, gynecological finding, colposcopic finding. PAPA test, HPV typing and laboratory findings due to the extensiveness of the study. Results: A comparison of the number of Caesarean sections in BiH before and now shows a statistically significant increase from about 6 caesareans per year to almost 21 Cesarean section per year (p<0.05). This increase led to a statistically significant decrease in perinatal mortality from 30 per thousand per year to only 6 per thousand per year (p<0.05). Complications after Cesarean section during both observed periods are dominated by subjective problems, followed by early complications after Cesarean section. According to the types of complications after Caesarean section, hemorrhages were the most numerous during both examined years, with 1 case of other complications and without a statistically significant difference between the observed years. There were no statistically significant differences in the duration of hospitalization, although in 2007 somewhat longer stay in the hospital after Caesarean section was recorded. Conclusion: Our study has shown that one of the most visible trends in modern perinatology is a significant increase in number of Cesarean sections. This is the basis of long-term side effects of Caesarean section, the frequency of which correlates with the increase in this surgical procedure.

I. Omerhodžić, Mirza Pojskić, K. Rotim, B. Splavski, L. Rasulić, K. Arnautović

SUMMARY Myxopapillary ependymomas (MPE) of the spinal cord are slow-growing benign tumors most frequently found in adults between 30 and 50 years of age. They arise from the ependyma of the filum terminale and are located in the area of the medullary conus and cauda. The recommended treatment option is gross total resection, while patients undergoing subtotal resection usually require radiotherapy. Complete resection without capsular violation can be curative and is often accomplished by simple resection of the filum above and below the tumor mass. Nevertheless, dissemination and distant treatment failure may occur in approximately 30% of the cases. In this paper, we propose an original MPE classification, which is based upon our personal series report concerned with tumor location and its correlation with the extent of resection. We also provide literature review, discussing surgical technique, tumor recurrence rate and dissemination, and adjuvant treatment. In conclusion, our findings suggest that MPE management based on the proposed 5-type tumor classification is favorable when total surgical resection is performed in carefully selected patients. Yet, further studies on a much broader model is obligatory to confirm this.

Dino Mustafic, D. Jokić, S. Lale, S. Lubura

In this paper, the Incremental Conductance maximum power point tracking (MPPT) algorithm is evaluated using an experimental setup consisting of two 75W photovoltaic (PV) panels connected in series. Humusoft MF 634 board is used to obtain and produce signals. The model was tested under changing solar irradiance conditions, and the acquired results show that it is able to respond to these changes appropriately.

Cristina Bin Honor Rodrigo M. Goodarz Rod T. Farshad Marisa Taddei Zhou Bixby Carrillo-Larco Danaei Jackson Fa, C. Taddei, Bin Zhou, Honor Bixby, R. Carrillo-Larco, G. Danaei, Rod Jackson, F. Farzadfar et al.

High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol—which is a marker of cardiovascular risk—changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million–4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world. From 1980 to 2018, the levels of total and non-high-density lipoprotein cholesterol increased in low- and middle-income countries, especially in east and southeast Asia, and decreased in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe.

P. Ovseiko, L. Gossec, L. Andreoli, U. Kiltz, L. V. Mens, Neelam Hassan, M. Leeden, H. Siddle et al.

Women represent an increasing proportion of the overall rheumatology workforce, but are underrepresented in academic rheumatology, especially in leadership roles [1].The EULAR Task Force on Gender Equity in Academic Rheumatology has been convened to establish the extent of the unmet need for support of female rheumatologists, health professionals and non-clinical scientists in academic rheumatology and develop a framework to address this through EULAR and EMEUNET.To investigate gender equity in academic rheumatology, an anonymous web-based survey was targeted at the membership of EULAR and Emerging EULAR Network (EMEUNET) and their wider networks. The survey was developed based on a narrative literature review [1], best practice from The Association of Women in Rheumatology, a survey of task force members and face-to-face task force discussions. Personal experiences were explored and 24 potential interventions to aid career advancement were ranked. Statistics were descriptive with significance testing for male/female responses compared using chi-squared/t-tests. The level of significance was set at p<0.001.A total of 301 respondents from 24 countries fully completed the survey. By profession, 290 (86.4%) were rheumatologists, 19 (6.3%) health professionals, and 22 (7.3%) non-clinical scientists. By gender, 217 (72.1%) were women, 83 (27.6%) men, and 1 (0.3%) third gender. By age, 203 (67.5%) were 40 or under. By ethnicity, 30 (10.0%) identified themselves as ethnic minority. A high proportion of respondents reported having experienced gender discrimination (47.2% total: 58.1% for women and 18.1% for men) and sexual harassment (26.2%: 31.8% and 10.8% respectively) (Figure 1). Chi-squared tests on the numbers on which these proportions were based showed statistically significant differences between women and men in having experienced gender discrimination (Χ2=36.959 (df=1), p <0.001) and sexual harassment (Χ2=12.633 (df=1), p <0.001). The highest-ranked interventions for career advancement regardless of respondents’ gender included: leadership skills training; speaking/presentation/communication skills training; information on training/career pathways; effective career planning training; support on grant writing applications; and high-impact scientific writing master-classes (Figure 2). Only 8 of 24 proposed interventions showed a significantly higher ranking (p<0.001) by female respondents and these typically related to promotion of female role models and gender-balance in committees, editorial boards and research funding (Figure 2).Figure 1.Perceived gender discrimination and sexual harassment, 301 responsesFigure 2.Mean perceived utility of potential interventions for career advancement by gender and statistically significant gender differences (p<.001), 300 responsesThe results of the survey will inform the development of task force policy proposals for interventions to support career advancement among EULAR and EMEUNET members. The identified interventions have potential to support career advancement of all rheumatologists, health professionals and non-clinical scientists regardless of gender.[1]Andreoli L, Ovseiko PV, Hassan N, Kiltz U, van Mens L, Gossec L, et al. Gender equity in clinical practice, research and training: Where do we stand in rheumatology? Joint, Bone, Spine: Revue du Rhumatisme. 2019;86(6):669-672.We gratefully acknowledge the rheumatologists, health professionals and non-clinical scientists who responded to the survey.Pavel V Ovseiko: None declared, Laure Gossec Grant/research support from: Lilly, Mylan, Pfizer, Sandoz, Consultant of: AbbVie, Amgen, Biogen, Celgene, Janssen, Lilly, Novartis, Pfizer, Sandoz, Sanofi-Aventis, UCB, Laura Andreoli: None declared, Uta Kiltz Grant/research support from: AbbVie, Amgen, Biogen, Novartis, Pfizer, Consultant of: AbbVie, Biocad, Eli Lilly and Company, Grünenthal, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, MSD, Novartis, Pfizer, Roche, UCB, Leonieke van Mens: None declared, Neelam Hassan: None declared, Marike van der Leeden: None declared, Heidi J Siddle: None declared, Alessia Alunno: None declared, Iain McInnes Grant/research support from: Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Janssen, and UCB, Consultant of: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Gilead, Janssen, Novartis, Pfizer, and UCB, Nemanja Damjanov Grant/research support from: from AbbVie, Pfizer, and Roche, Consultant of: AbbVie, Gedeon Richter, Merck, Novartis, Pfizer, and Roche, Speakers bureau: AbbVie, Gedeon Richter, Merck, Novartis, Pfizer, and Roche, Florence Apparailly: None declared, Caroline Ospelt Consultant of: Consultancy fees from Gilead Sciences., Irene van der Horst-Bruinsma Grant/research support from: AbbVie, Novartis, Eli Lilly, Bristol-Myers Squibb, MSD, Pfizer, UCB Pharma, Consultant of: AbbVie, Novartis, Eli Lilly, Bristol-Myers Squibb, MSD, Pfizer, UCB Pharma, Elena Nikiphorou: None declared, Katie Druce Speakers bureau: Pfizer and Lilly, Zoltán Szekanecz Grant/research support from: Pfizer, UCB, Consultant of: Sanofi, MSD, Abbvie, Pfizer, Roche, Novertis, Lilly, Gedeon Richter, Amgen, Alexandre Sepriano: None declared, Tadej Avcin: None declared, George Bertsias Grant/research support from: GSK, Consultant of: Novartis, Georg Schett Speakers bureau: AbbVie, BMS, Celgene, Janssen, Eli Lilly, Novartis, Roche and UCB, Anne Maree Keenan: None declared, Laura C Coates: None declared

Aida Kasumović, Ines Matoc, D. Rebić, N. Avdagić, Tarik Halimić

Introduction: Optical coherence tomography angiography (OCT-A) is a useful diagnostic tool for assessing eyes’ health in patients with chronic diseases, such as diabetes, hypertension, Parkinson’s disease and chronic kidney disease (CKD). Aim: To detect changes in macular structure and retinal vascular meshwork in the macular area and peripapillary in patients with chronic kidney disease (CKD). Methods: This cross-sectional study included 80 eyes of patients with CKD in stages 2, 3 or 4, who were followed-up in the Nephrology Clinic of University Clinical Center Sarajevo. All patients were categorized according to the stage of CKD. All patients were scanned by a high-speed 840-nm-wavelength spectral-domain optical coherence tomography instrument (RTVue XR Avanti; Optovue, Inc, Fremont, California, USA). Blood flow was detected using a split-spectrum amplitude-decorrelation angiography algorithm. A fully automated microstructural analysis of the foveal avascular zone (FAZ), FAZ perimeter, foveal vessel density in a 300-μm area around the FAZ (FD), nonflow area, flow index in superficial and deep vascular plexus, choriocapillary flow, vascular density, radial peripapillary capillary density was performed. Results: When comparing patients with CKD stage 2 and stage 3 there were no statistically significant changes in microvascular parameters on OCT angiography, as well as when comparing patients with CKD stage 3 and stage 4. But in the comparison between patients with less developed CKD (stage 2) and terminal CKD (stage 4) there was a significant difference between some microvascular parameters such as FAZ area, FAZ perimeter, choriocapillary flow. Conclusion: Many studies demonstrated that evaluation of the microvascular changes in different retinal layers using SS-OCTA may be considered as a key to assessing the systemic perfusion status. Evaluation of retinal microvasculature may ease the management and approach of patients with CKD, having in mind that the retinal and the kidney vascular network are, concerning structure, development and the function, very similar.

Abstract The author analyses volunteering in Bosnia and Herzegovina, focusing on women’s activism in connection with values associated with the concept of civil society, such as solidarity, equity, and reciprocity. Civil society in Bosnia and Herzegovina generally suffers from fragmentation, donor-driven approaches, insufficient transparency and low trust among the general population, all of which present obstacles to voluntary work, as does a legal framework which is certainly not conducive to volunteering. Unlike organizations that do no more than promote the interests of their members, or groups connected to or controlled by political parties, women’s organizations are often seen as undertaking genuine activism. The author reveals differences in attitudes to volunteer work among individual women in organizations of varying sizes, explaining that those differences depend to some extent on women’s locations, ages or experience. Both inter-group and intra-group dynamics, including women’s networks, provide additional insights into voluntarism, especially with regard to the value of solidarity.

Different types of transient phenomena are found in power systems. Switching transients in power systems have always been a matter of concern in insulation coordination studies. The reactors in power system are widely used elements which purpose is to provide stable power flow in normal conditions and to reduce dynamical and thermal stresses during short circuits and some other faults. Many shunt reactors are switched frequently, even daily. Shunt reactor switching imposes a unique and severe stress on the connected system and the circuit breaker. This paper presents study of overvoltages due to shunt reactor switching in 400 kV substation.

Lightning is the main cause of line outages on overhead distribution lines, especially for lines located in mountain areas and without line surge arresters installed along the line. This paper is dedicated to lightning outage performance of distribution line “Kotor – Lovćen” that operates in mountain Lovćen area. Shielding failure rate, shielding failure flashover rate and back flashover rate are calculated using Sigma Slp software. Lightning data collected by two advanced lightning activity monitoring systems are analyzed and used in number of simulations conducted for purposes of this paper.

Structural size optimization of a device for external bone fixation within a formed iterative hybrid optimization algorithm was presented in this paper. The optimization algorithm was in interaction with the algorithms for generative design and FEM analysis and completely integrated within CATIA CAD/CAM/CAE system. The initial model, representing the current design of the bone external fixation device Sarafix, was previously verified by experimental testing. The formed hybrid optimization algorithm was created as an integration of the global (SA method) and local (CG method) algorithm. The constraints of the optimization model are the clinical limitations of the interfragmentary displacements and the material strength. The optimized design has less weight, greater rigidity and less transverse interfragmentary displacements at the point of fracture compared to the current design.

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