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In every edition of the Highway Capacity Manual (HCM) until 2016, three levels of capacity analysis were defined: operational, project and planning analysis. The level of detail of each analysis is a function of purpose, breadth of access and available information. Planning analysis determines capacity in the earliest stages of planning, when small amount of data and information is available. The planning procedure is based on the AADT forecast and macro traffic simulation. Often, the usage of simulation models can lead to errors, and for these reasons, when analyzing traffic demands, it is necessary to carry out a check when more informations are available. Planning analyzes from the HCM manual are generally focused on broad issues such as initial problem identification, road design concept, and when alternatives are compared. These analyzes are suitable for evaluating proposed system measures, such as heavy vehicle lane usage control, highway ramp metering, and other applications of intelligent transportation systems. The methodology recommended in HCM implies the use of default input values, i.e. table of generalized values. Given that the recommended capacity values are based on typical road profiles and traffic flow characteristics in the USA, the paper provides a detailed capacity analysis at the planning level for local conditions - four standard geometric two-lane and highway profiles. Capacities are calculated for different values of design hourly volume, design speed, peak hour factor, commercial vehicle impact and terrain type, in order to compare with the generalized capacity tables from HCM2010. The comparative analysis indicates differences in the calculated capacity values, and for that reason the obtained values are recommended for use in model simulations for local conditions in the Republic of Serbia.

The analysis of the large infrastructure projects effects reveals frequent errors in the intensity of traffic flows or investment costs estimation, which can jeopardize the established feasibility of the project. This reflects the importance of ex-post analyzes because they provide valuable information on the fulfillment of project goals, ie they are useful for the purpose of efficiency monitoring and cost-benefit analysis (CBA) improvement. A feasibility study for the construction of the second carriageway of the E75 freeway, on the section from Novi Sad to Belgrade, was done in 2003, and the results of a detailed traffic and economic analysis showed the absolute economic feasibility of this project. ex-post analysis of key factors enabled the identification of realized effects and the identification of all deviations, both in time dynamics and in economic indicators of costs/benefits. The results of the first conducted ex-post analysis of infrastructure projects in Serbia showed that the Mean Percentage Error (MPE) in the traffic forecast is -16.42%, and that investment costs are exceeded by 9.3%. The obtained internal rate of return (IRR) is less than 33% to 50% depending on the observed variant, but even the most critical value of 7.03% showed that the project was economically feasible.

Peripheral arterial disease is one of the manifestations of atherosclerosis that manifests itself primarily in the peripheral arteries of the lower extremities and the aortoiliac segment. The largest number of patients, about 90%, have functional ischemia (Stage IIa and IIb according to Fontaine). For these patients, the therapy of choice is medication consisting of a combination of acetylsalicylic acid, cilostazol and pentoxifylline. Smoking is a very significant risk factor for the development of peripheral arterial disease and is also one of the most significant outcome modifiers. The study included 82 patients diagnosed with functional ischaemia of the lower extremities treated at the Clinic of Vascular Surgery of the Clinical Center in Niš, starting from January 2020 to December 31, 2020. Smoking was present in 76.82% of respondents. In the research conducted, 48.78% of respondents used pentoxifylline + acetylsalicylic acid, while 51.22% of respondents were treated with cilostazol + acetylsalicylic acid. Results showed the extension of the claudication distance after 6 months was significantly greater in the group of patients who used cilostazol + acetylsalicylic acid. In a subgroup of patients smoking > 20 cigars daily and with > 20 years of smoking there was a significant increase in claudication distance after 6 months in the cilostazol + acetylsalicylic acid group compared to pentoxifylline + acetylsalicylic acid group. In conclusion, the number of cigarettes/day and length of smoking experience have a significant effect on the applied therapeutic modality in patients with peripheral arterial disease. Cilostazol + acetylsalicylic acid therapy was more effective than pentoxifylline + acetylsalicylic acid. [ABSTRACT FROM AUTHOR]

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Aim: Beside the intention of early detection and optimal treatment of deep venous thrombosis (DVT), the aim of this study was to investigate the influence of chronobiological rhythms on the etiopathogenesis of unprovoked deep vein thrombosis of the lower limbs with monitoring of seasonal variations in biochemical parameters. Patients and methodology: The prospective clinical trial included all consecutive hospitalized patients and outpatients diagnosed with DVT at the Vascular Surgery Clinic of the Clinical Center in Niš, starting from January 2013 to December 2014. Results: There was no statistically significant difference in correlation between the distribution of the incidence of DVT of the lower limbs (p = 0.582), sex (p = 0.350), age (p = 0.385) and localization (p = 0.886) and the seasons. Creatinine levels were significantly higher in patients who developed DVT in spring than in those who developed DVT in winter (p < 0.05), while LDL cholesterol levels were significantly higher in patients diagnosed with DVT in winter than in those diagnosed with DVT in autumn (p < 0.05). Conclusion: According to the results of the study, it can be concluded that in the territory of South Serbia, the seasons are not significantly related to the incidence, sex, age and localization of unprovoked DVT of the lower limbs. Creatinine levels were significantly higher in patients who developed DVT in spring than in those who developed DVT in winter, while LDL cholesterol levels were significantly higher in patients during winter than during autumn. [ABSTRACT FROM AUTHOR]

Speed, as one of the basic parameters of the traffic flow, has a great importance in terms of efficiency (level of service, travel time) and safety (number of traffic accidents, consequences and risk of accident occurrence). Speed management includes a series of measures that are applied in order to achieve the balance between safety and efficiency in the traffic flow. One of the most important measures for achieving this goal is to define a credible speed limit, i.e. the speed limit that would allow maximization of the capacity and level of service of the observed section, or minimization of users' costs and the risk of traffic accident occurrence. Considering the fact that improper and unadjusted speed causes a number of significant negative effects, the aim of this paper is to carry out the analysis of the credibility of the existing speed limits, i.e. to determine the factors that impact the speed on two-lane sections of valley roads. In order to achieve this, field research in real-world conditions was carried out using the floating vehicle method and an Android phone application. This paper analyzed the speed on the cross-section (time-mean speed). However, it also analyzed the traffic flow speeds on the entire homogeneous impact segment on the basis of automated traffic counters (micro level), as well as on the macro level, i.e. along the six analyzed sections of two-lane rural valley roads (space-mean speed). Also, empirical research determined the speed limit values on the selected sections and free flow speeds on the basis of the Linear Model and by applying the HCS software. Within the speed analysis, the values of operating speeds were determined based on analytical models and methods. In order to obtain a clearer image of the credibility of the existing speed limits, an analysis of the speed limit violations according to classes was carried out. [ABSTRACT FROM AUTHOR]

Copyright of Acta Medica Medianae is the property of Acta Medica Medianae and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Medica Medianae is the property of Acta Medica Medianae and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background/Aim. Popliteal artery aneurysm (PAA) is the most common peripheral artery aneurysm and the second most common aneurysm following abdominal aortic aneurysm (AAA). Still, its incidence is rare, and treatment is non-standardized. The collection of data in a multicenter registry could improve the diagnosis and treatment of PAA. SerbVasc is a newly established data collection collaboration among vascular centers in Serbia. The aim of this study was to present common surgical practices in the diagnosis and treatment of patients with PAA in hospitals in Serbia. Methods. Vascular centers in Serbia that accepted the invitation collected data retrospectively concerning patients operated on for PAA from 2012 to 2018. Data regarding symptoms, preoperative diagnostics, vascular and endovascular techniques, and postoperative results were collected. This data set was submitted to the VASCUNET international project of PAA for data analysis between the countries. The same data set was used for a detailed analysis of the contemporary treatment of PAA in six hospitals in Serbia: University Clinical Center of Serbia, "Dedinje" Cardiovascular Institute, Military Medical Academy, University Clinical Center Novi Sad, University Clinical Center Niš, and General Hospital Užice. Results. From 2012 to 2018, in six hospitals in Serbia, data for 342 procedures on treating PAA were collected for 329 (96.2%) men and only 13 (3.8%) women. The incidence of PAA repair was 6.8 operations per million inhabitants a year. The mean age of patients was 64.34 years (ranging from 29 to 87). A total of 223 (65.8%) elective procedures were performed. Amputation and hospital survival were considered the main outcomes. Thrombosis was recorded in 110 (32.5%) patients as a cause for surgery, and rupture was recorded in 5 patients. The mean diameter of the aneurysm was 35.3 mm, and a slightly larger diameter was recorded in ruptured aneurysms - 43.8 mm on average. Both synthetic and vein grafts were used in elective and urgent procedures equally. Endovascular procedures were performed in 6 (1.8%) cases. Conclusion. This study confirms the importance of registry-based collection of data and their analysis. It showed that the national incidence of PAA in Serbia is low and that well-organized, even institutionbased, screening algorithms should improve identifying such patients and increase the number of electively treated PAA. Educating vascular surgeons to use the posterior approach could improve vascular healthcare. [ABSTRACT FROM AUTHOR]