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Characteristics of inflammatory mediators in systemic circulation of criticaly ill patients with secondary sepsis of peritonitis, pancreatitis and severe trauma
No full textUvod.Uloga imunskog odgovora u sepsi i dalje nije potpuno razjašnjena i predmet je
istraživanja. Ciljevi:Utvrditi razlike u citokinskom profilu kod kritično
obolelih bolesnika sa sepsom porekla pankreatitisa, peritonitisa i traume u odnosu
na osnovno stanje, uzročnika i proceniti prognostičku vrednost u odnosu na ishod.
Metode.Uzorci krvi uzeti su od 125 bolesnika sa sepsom porekla peritonitisa,
pankreatitisa i traume, iz kojih su određeni nivoi proinflamatornih: TNF-α, IL-1α,
IL-1β, IFN-γ, IL-6, IL-8, IL-12r70, IL-17A, IP 10, MCP1, MIP-1α, MIP-1β i antiinflamatornih citokina: IL-33, IL-31, IL-27, IL-13, IL-10, IL-4, prvog, a potom trećeg
i petog dana. Rezultati. Nivoi TNF-α, MIP-1β, IL-1α, IP 10, MCP-1, IL-27, IL-33 i IL10 bili su veći u grupi peritonitisa u odnosu na pankreatitis prvog dana merenja.
Poređenjem nivoa citokina između prvog, trećeg i petog dana merenja u grupi
posttraumatske sepse ustanovljene su razlike za proinflamatorne: TNF-α, IL-1β, IP
10, IL-8, MIP-1β, IL-17A, IFN-γ, MIP-1α, IL-1α, IL-12p70 i anti-inflamatorne
citokine: IL-33, IL-10, IL-31, IL-13. Razlike u nivoima citokina u pogledu
bakterijemije ustanovili smo kod svih citokina, osim IL-8, trećeg dana merenja.
Jedini prediktor letalnog ishoda prvog dana merenja bio je IL-17A kod bolesnika sa
sepsom porekla peritonitisa. Zaključci. Citokinski profil kod pacijenata sa
sepsom porekla peritonitisa pokazao je veće vrednosti u odnosu na pacijente sa
sepsom kod teškog pankreatitisa u prvom danu merenja. Najniži nivoi citokina
izmereni su kod pacijenata sa polimikrobnom hemokulturom. Niska koncentracija
IL-17A kod pacijenata sa septičkim peritonitisom predviđa smrtni ishod.Introduction: The role of the sepsis-related immune response has not been fully clarified,
and still remains a subject matter of investigations. Objectives: to determine the differences
in the cytokine profile in critically ill patients with sepsis of pancreatitis, peritonitis and
trauma in relation to the underlying condition, the causative agent and to evaluate the
prognostic value in relation to the outcome. Methods. Blood samples were taken from 125
patients with sepsis of peritonitis, pancreatitis and trauma origin, from which the levels of
pro-inflammatory factors were determined:TNF-α, IL-1α, IL-1β, IFN-γ, IL-6, IL-8, IL-12p70,
IL-17A, IP10, MCP-1, MIP-1α, MIP-1β and anti-inflammatory cytokines IL-33, IL-31, IL27, IL-13, IL-10, IL-4, the first, and then on the third and fifth day. Results. The levels of
TNF-α, MIP-1β, IL-1α, IP 10, MCP-1, IL-27, IL-33 and IL-10 were higher in the group of
peritonitis compared to pancreatitis on the first day of measurement. By comparing cytokine
levels between the first, third and fifth day of measurement in the post-traumatic sepsis
group, differences were found for pro-inflammatory: TNF-α, IL-1β, IP 10, IL-8, MIP-1β, IL17A, IFN-γ, MIP-1α, IL-1α, IL-12p70 and anti-inflammatory cytokines:IL-33, IL-10, IL-31,
IL-13. Differences in cytokine levels with regard to bacteremia were found for all cytokines,
except for IL-8, on the third day of measurement. The only predictor of lethal outcome on the
first day of measurement was IL-17A in patients with sepsis of peritonitis origin.
Conclusions. Cytokine profile in patients with sepsis of peritonitis origin showed higher
values compared to patients with sepsis in severe pancreatitis on the first day of
measurement. The lowest cytokine levels were measured in patients with polymicrobial blood
cultures. Low concentration of IL-17A in patients with septic peritonitis predicts fatal
outcome
Application of flotation tailings in cement pastes for mining works in order of environmental protection
Get PDFУ дисертацији су приказани резултати испитивања цементне пасте (CPB – cemented paste backfill) добијене од флотацијске јаловине као основног материјала, цемента и воде. Циљ је био добити цементну пасту са што мањим учешћем цемента, која ће задовољити основни механички захтев - притисну чврстоћу од најмање 1 до 1,5 MPa након 28 дана. Анализирани су различити односи компонентних материјала и добијено је да је оптимално решење за ову врсту проблема, паста која садржи 5% цемента, 24% воде и 71% флотацијске јаловине. Применљивости одабране цементне пасте за запуњавање у подземној експлоатацији методом коморно-стубног експлоатисања минералних сировиниа потврђена је и нумеричким моделом. Такође, показано је да овако добијена цементна паста може служити и као баријера у подземним откопима у циљу очувања подземних вода и животне средине, чиме је дат додатни допринос одрживом развоју. U disertaciji su prikazani rezultati ispitivanja cementne paste (CPB – cemented paste backfill) dobijene od flotacijske jalovine kao osnovnog materijala, cementa i vode. Cilj je bio dobiti cementnu pastu sa što manjim učešćem cementa, koja će zadovoljiti osnovni mehanički zahtev - pritisnu čvrstoću od najmanje 1 do 1,5 MPa nakon 28 dana. Analizirani su različiti odnosi komponentnih materijala i dobijeno je da je optimalno rešenje za ovu vrstu problema, pasta koja sadrži 5% cementa, 24% vode i 71% flotacijske jalovine. Primenljivosti odabrane cementne paste za zapunjavanje u podzemnoj eksploataciji metodom komorno-stubnog eksploatisanja mineralnih sirovinia potvrđena je i numeričkim modelom. Takođe, pokazano je da ovako dobijena cementna pasta može služiti i kao barijera u podzemnim otkopima u cilju očuvanja podzemnih voda i životne sredine, čime je dat dodatni doprinos održivom razvoju. The dissertation presents the results of testing cement paste (CPB - cemented paste backfill) obtained from flotation tailings as the basic material, cement and water. The goal was to obtain a cement paste with as little cement content as possible, which would satisfy the basic mechanical requirement, which is to achieve a compressive strength of at least 1 to 1.5 MPa after 28 days. Various ratios of component materials were analyzed and it was found that the optimal solution for this type of problem is a paste containing 5% cement, 24% water and 71% flotation tailings. The applicability of the selected cement paste for filling in underground exploitation using the method of chamber-pillar exploitation of mineral raw materials, was also confirmed by a numerical model. It was also shown that the cement paste obtained in this way can also serve as a barrier in underground excavations in order to preserve groundwater and the environment, thus making an additional contribution to sustainable development
A Comparative Study
Get PDFUvod: Ova doktorska disertacija je rezultat teorijskog i empirijskog istraživanja pojedinih segmenata svakodnevice studentske populacije, u specifičnim javno-zdravstvenim i društvenim okolnostima COVID-19 pandemije. Najpre, disertacija nastoji da doprinese objašnjavanju i dubljem razumevanju svakodnevice studenata u novim svakodnevnim (životnim), društvenim okolnostima izazvanim COVID-19 pandemijom. Teorijsku osnovu disertacije čini uvezivanje teorija svakodnevnog života, vanrednih društvenih okolnosti i studentske omladine. Empirijsku osnovu disertacije čini istraživanje zasnovano na mešovitom istraživačkom planu. Ono je podrazumevalo realizaciju anketnog istraživanja i polustrukturisanih intervjua, na populaciji studenata Univerziteta u Novom Sadu (R. Srbija) i Primorskog Univerziteta (R. Slovenija) tokom 2022. godine. Istraživanje je pružilo uvid u specifičnosti svakodnevice studenata u srpskom i slovenačkom društvu, sa posebnom osvrtom na: fizičku aktivnost, sedentarnost, spavanje, ishranu, organizaciju studijskih obaveza, društveni život, mentalno blagostanje i COVID-19 pandemiju kao (novo životno) iskustvo. Cilj istraživanja podrazumevao je upoređivanje uticaja pandemije i način adaptiranja studenata sportskih i ostalih nauka, na vanredne svakodnevne društvene okolnosti (COVID-19 pandemije). Metod: Uzorak ispitanika sačinjava 670 studenata (starosti 23.30 ± 1.98; 46.3% muških i 53.7% ženskih osoba; 43.1% sportskih i 56.9% ostalih nauka) sa Univerziteta u Novom Sadu iz Srbije i sa Primorskg Univerziteta iz Slovenije. Za prikupljanje podataka korišćen je anketni upitnik (n = 670) i polu-strukturisani intervju (n = 40) u vremenskom periodu od marta do jula 2022. godine. Kvantitativni podaci su analizirani pomoću SPSS programa, a kvalitativni QDA Miner. Rezultati: Na studente sportskih nauka (studijskog profila kineziologije, sporta i fizičkog vaspitanja) restriktivne mere su u manjoj meri uticale u poređenju sa studentima ostalih nauka i studijskih profila, te su na uspešniji način adaptirali svakodnevicu vanrednim okolnostima izazvanim COVID-19 pandemijom. Diskusija: Odlike teorije Z. Baumana, tim pre što korespondiraju podacima dobijenih terenskim istraživanjem. Ujedno, ti podaci prikazuju konkretne faze transformacije svakodnevice studentske omladine, što je važno i kao polazna osnova za naredna kompatibilna istraživanja.Introduction: This doctoral dissertation is the result of theoretical and empirical research of certain segments of the daily life of the student population, in specific public health and social circumstances of the COVID-19 pandemic. First, the dissertation aims to contribute to the explanation and deeper understanding of the everyday life of students in new everyday (life), social circumstances caused by the COVID-19 pandemic. The theoretical basis of the dissertation is the integration of theories of everyday life, extraordinary social circumstances, and student youth. The empirical basis of the dissertation is research based on a mixed research plan. It involved conducting a survey and semi-structured interviews, on the population of students of the University of Novi Sad (R. Serbia) and the University of Primorska (R. Slovenia) during 2022. The research provided insight into the specifics of the daily life of students in Serbian and Slovenian society, with a special focus on: physical activity, sedentary lifestyle, sleep, nutrition, organization of study obligations, social life, mental well-being, and the COVID-19 pandemic as a (new life) experience. The aim of the research was to compare the impact of the pandemic and the way of adapting students of sports and other sciences to extraordinary everyday social circumstances (COVID-19 pandemic). Method: The sample of respondents consists of 670 students (aged 23.30 ± 1.98; 46.3% male and 53.7% female; 43.1% sports and 56.9% other sciences) from the University of Novi Sad in Serbia and the University of Primorska in Slovenia. A survey questionnaire (n = 670) and semi-structured interview (n = 40) were used to collect data from March to July 2022. Quantitative data were analyzed using the SPSS program, and qualitative data were analyzed using QDA Miner. Results: Restrictive measures had a lesser impact on students of sports sciences (study profile of kinesiology, sports, and physical education) compared to students of other sciences and study profiles. Discussion: The characteristics of Z. Bauman’s theory, especially as they correspond to the data obtained by field research. At the same time, these data show concrete phases of transformation of the everyday life of student youth, which is important as a starting point for future compatible research
Sinteza i karakterizacija kopolimernih hidrogelova na bazi N-izopropilmetakrilamida i N-izopropilakrilamida za formulacije sa kurkuminom
No full textThe aim of the doctoral dissertation was the development of a new matrix system based on a smart polymer carrier with an incorporated curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex to increase the solubility of curcumin and achieve its modified release.
For this purpose, series of thermosensitive hydrogels based on N-isopropylmethacrylamide and N-isopropylacrylamide monomers were synthesized by free-radical polymerization with a different content of monomers and crosslinker. The characterization of the synthesized hydrogels was performed using the FTIR, XRD, SEM and DSC methods. The content of unreacted monomers was determined using the HPLC method.
The degree and rate of swelling of hydrogels depending on the temperature, monomer content and crosslinker were determined gravimetrically. The swelling kinetics of p(NiPMAm-co-NiPAm) hydrogels was investigated, and the central composite design was applied as a mathematical model to describe the equilibrium swelling process of p(NiPMAm-co-NiPAm) hydrogels depending on the composition of the copolymer and the temperature of the surrounding medium.
An inclusion complex of curcumin with 2-hydroxypropyl-β-cyclodextrin was prepared in order to increase the solubility of curcumin and characterized by FTIR, SEM, XRD, DSC and 1H-NMR methods. The applied characterization methods confirmed the incorporation of curcumin into the cavity of 2-hydroxypropyl-β-cyclodextrin, and the solubility phase showed that the solubility of curcumin in water increases. An increased antioxidant and antimicrobial activity of curcumin in the inclusion complex is a consequence of its increased solubility in water. The influence of curcumin and the curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex on the textural characteristics of Carbopol gel was investigated over the course of time. The results of the textural analysis show that curcumin and curcumin in the inclusion complex do not lead to statistically significant changes in the textural parameters of Carbopol gel over a 14-day period, which indicates the physical stability of the formulations.
The curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex was incorporated into the synthesized and characterized p(NiPMAm-co-NiPAm) hydrogels. The characterization of the synthesized hydrogels with the curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex was performed using the FTIR, XRD, SEM and DSC methods, where the presence of curcumin in the hydrogels was confirmed. The synthesized p(NiPMAm-co-NiPAm) hydrogels provide a sustained release of curcumin. The Korsmeyer-Peppas model best describes the release of curcumin from the matrix system, while the mechanism of curcumin
release is based on the diffusion from the polymer matrix of hydrogels
Три (п)огледа/диорама као просторна транспозиција графичког листа/изложба графика и објекта
No full textReactivity on the polygraph control questions test in a real situation and experiment : doctoral dissertation
No full textОвим истраживањем се испитује ваљаност полиграфског испитивања у
полицији и врши поређење карактеристика физиолошких реакција испитаника у
експерименталним и реалним ситуацијама. Претпоставка је да ће они који
покушавају да обмањују приликом полиграфског тестирања имати дистинктивне
физиолошке реакције које су последица доживљаја стреса или страха услед претње
да ће бити откривени и сносити одређене последице. Циљ је испитивање
реактивности путем полиграфскoг Теста са контролним питањима (eng. Control
Question Test) на различитим типовима питања у различитим ситуацијама, као и
оповргавање тврдње да примена CQT често доводи до погрешних позитивних
налаза због стреса искрених испитаника. Резултати су показали да је полиграфско
испитивање успешно у откривању укључености у кривично дело, да постоје
дистинктивне физиолошке карактеристике реактивности осумњичених и да је
реактивност на контролним питањима која се односе на моралне прекршаје у
прошлости независна, било да је реч о експерименту или о реалној ситуацији.
Последњи налаз представља прилог употреби CQT, теста који се најчешће
примењује у полицијама које користе полиграфско испитивање.This research examines the validity of the polygraph examination in the police
and compares the characteristics of the physiological reactions of the examinees in
experimental and real situations. The assumption is that those who attempt to deceive
during a polygraph test will have distinctive physiological reactions that are the result of
experiencing stress or fear due to the threat of being discovered and suffering certain
consequences. The goal is to examine reactivity through the polygraph method CQT (eng.
Control Question Test) on different types of questions in different situations, as well as
refuting the claim that the application of CQT often leads to false positive findings due to
the stress of honest respondents. The results showed that polygraph examination was
successful in detecting involvement in a crime, that there were distinctive physiological
characteristics of the suspects' reactivity, and that reactivity on control questions related
to moral offenses in the past was independent, whether it was an experiment or a real
situation. The latest finding is a contribution to the use of CQT, the test most commonly
used by police officers who use polygraph testing
Unapređenje procene kvaliteta podataka o smrtnom ishodu u Srbiji određivanjem indeksa performansi vitalne statistike
No full textThe traditional approach to mortality quality assessment was based on evaluating
the completeness of vital statistics and the proportion of R diagnoses, while the new
principle determines the Vital Statistics Performance Index for Quality-VSPI(Q).
The goals of the doctoral dissertation are to improve the assessment of the quality
of data on death outcomes by determining the VSPI(Q) index in Serbia from 2005
to 2019 and assessing the level of knowledge and attitudes of physicians when
filling out the death certificate (DC).
In the first part of the research, the ANACONDA software package was used to
assess the quality of death data, which analyses the accuracy and completeness of
mortality data with demographic and epidemiological global estimates. In the
second part of the research, a modified Mid-America Heart Institute (MAHI) Death
Certificate Scoring System determined the assessment of physicians' knowledge.
The mortality data in Serbia was assessed as medium quality for the entire fifteenyear
period (VSPI(Q) score of 67.2%). A constant increase in the quality of
mortality data was based on the increase in the VSPI(Q) score from 55.6 (medium
quality) to 70.2 (high quality) in the follow-up period. It was found that 24.2%
belonged to garbage codes (GC), while 18.5% belonged to insufficiently specified
causes of death. Death due to external factors is represented by 0.8%, below the
global average of 5-10%. According to the GC typology, the most common error
belongs to category 3 (24.7%), representing the intermediate cause of death. The
most common ill-defined diagnosis for both sexes is nonspecific cardiomyopathy
(I42.9). As a result of the ANACONDA analysis, 9.2% of GC in females and 9.1%
of GC in males were successfully redistributed. A strong positive correlation was
found between the VSPI(Q) score and sociodemographic indices for Serbia. The
physician's knowledge of coding DC is suboptimal for all three cases. The optimal
level of knowledge was achieved by 51.4% of physicians for coding the natural
death, 42.3% for coding the violent death, and 19.5% for coding the undetermined
death. Predictors of better knowledge are education, frequency of filling out DCs,
and the number of completed DCs.
The results indicate an increase in the quality of mortality data in Serbia and a large
percentage of GC in the fifteen years, reflected in physicians' suboptimal
knowledge. For this purpose, it is necessary to adapt education and focus on the
critical aspects of each cause of death
Dileme i paradoksi ključnih poreskih elemenata - uzroci kontinuiranih reformi poreza na dobit preduzeća
No full textContemporary tax systems and the latest economic trends have raised questions about the persistence of corporate income tax despite current propositions that this form of taxation, along with its stabilization and development component, positively impacts economic growth even in conditions of cyclical fluctuations. Thus, the once-celebrated "tax ideal" has been subjected to continuous criticism in economic literature and ongoing reforms in tax systems, making it the "epicenter" of contemporary financial doctrine.
The goal of this work is to provide grounded assessments of the presence of dilemmas and paradoxes in the elements of corporate income taxation based on appropriate descriptive and empirical analyses, identify key determinants of corporate income tax revenue, and propose alternative reform drafts for this taxation form. With the intention to test the theoretically founded concept of profit taxation in a real environment and determine its significance therein, the doctoral research approached empirical verification using statistical and econometric methods on a sample of EU, OECD, and RS. The theoretical analysis of key tax elements illuminated the most significant dilemmas of corporate income tax and highlighted paradoxes, thereby enabling the creation of a conceptual framework for examining determinants and solving puzzles that accompany it. An assessment of effective tax rates, through data processing from tax balances, indicated a high degree of tax liability management by the most successful companies and significant repercussions on corporate income tax revenues. Empirical analysis of tax rate changes, driven by tax competition, confirmed their asymmetry and divergent trends relative to corporate income tax revenues. Although tax incentives are specifically designed to reduce corporate income tax revenues, which is why they are referred to as "tax expenditures" in the literature, the dissertation confirms a paradox: effective tax burden on the corporate sector can lead to an increase in corporate income tax revenues. Consequently, a proposal for their parameterization has been defined through a detailed analysis of the efficiency of tax incentives in RS. By conducting an estimation of the impact of analyzed determinants on corporate income tax revenues, seven models of empirical research were created to analyze the impact of tax and economic policy, yielding the following results: 1. the statutory corporate income tax rate positively affects corporate income tax revenues; 2. the effective corporate income tax rate positively affects corporate income tax revenues; 3. the effective marginal corporate income tax rate positively affects corporate income tax revenues; 4. the statutory income tax rate positively affects corporate income tax revenues; 5. tax revenues positively affect corporate income tax revenues; 6. inflation positively affects
corporate income tax revenues; 7. globalization positively affects corporate income tax revenues; 8. public debt negatively affects corporate income tax revenues; 9. unemployment negatively affects corporate income tax revenues; 10. the growth of state spending for final consumption negatively affects corporate income tax revenues; 11. the growth of state revenues positively affects corporate income tax revenues; 12. control of corruption in the country positively affects corporate income tax revenues; 13. control of the regulatory function of the executive authority positively affects corporate income tax revenues; 14. an increase in imports and a decrease in exports affect an increase in corporate income tax revenues; 15. human capital significantly contributes to increasing corporate income tax revenues.
Identifying dilemmas and paradoxes of key tax elements and conducted empirical analyses showed the impossibility of harmonizing the current concept of corporate income tax worldwide due to its great complexity. In this sense, guidelines for creating its reform, which would correspond to contemporary business conditions, were conceived
Karijerna sidra i preduzetničke namere studentske populacije u Republici Srbiji
No full textIndividuals who highly value autonomy and independence and, in addition, have a high tolerance for risk and uncertainty, creativity, innovation, and the like, may decide to build an entrepreneurial career. However, in order to build this kind of career, it is necessary to have the intention to start an entrepreneurial venture. According to Icek Ajzen's theory of planned behavior, the main predictors of entrepreneurial intentions are personal attitude about entrepreneurship, the influence of prominent individuals from the person's environment and entrepreneurial self-efficacy. These direct predictors are influenced by a multitude of exogenous factors, such as the individual's career anchors, their socio-demographic characteristics, economic factors, and others. Bearing in mind the importance that entrepreneurship has for the economic prosperity of countries, especially those with low GDP per capita, which includes the Republic of Serbia, it is very important to identify at the earliest possible stage all the factors that have an impact on the entrepreneurial intentions of individuals in order to their effect through various mechanisms and incentives additionally encouraged. Having in mind that one of the key factors influencing entrepreneurial intention is an appropriate career anchor, i.e. such a set of talents, motives and values that match the characteristics of an entrepreneurial career, the doctoral dissertation aims to determine whether the career anchors of the student population in the Republic of Serbia can be related to the intention to become entrepreneurs, as well as whether the career anchors of the student population in the Republic of Serbia, characteristic of entrepreneurs, influence their intention to become entrepreneurs. In addition, the goal of the dissertation is to determine whether the influence of career anchors on students' entrepreneurial intentions is mediated by predictors viewed from the perspective of the theory of planned behavior. The research sample consisted of 445 students. The results of the research showed that there is a positive influence of the career anchors "entrepreneurial creativity", "general managerial competence" and "autonomy/independence" on the entrepreneurial intentions of the respondents, as well as that the effect of those career anchors on the entrepreneurial intentions of the student population in the Republic of Serbia is mediated by personal attitudes about entrepreneurship, the influence of prominent individuals from the person's environment and entrepreneurial self-efficacy. The theoretical contribution of the doctoral dissertation is reflected in the fact that the literature on career management is supplemented with a new approach in studying the entrepreneurial intentions of the student population, while the practical contribution is reflected in the fact that, based on the research results,
measures and policies for career counseling of students in the Republic of Serbia can be created in order to encourage entrepreneurship
