176 research outputs found
Public debt sustainability in Serbia before and during the global financial crisis
We have analyzed the behaviour
of primary fiscal balance and
public debt in Serbia before and in the aftermath
of the global financial crisis. The
results of our analysis are: i) public debt to
GDP ratioexhibits (near) unit root behaviour
with an overall upward time trend; ii)
the response of primary fiscal balance to
public debt has been insufficient to mean
revert the upward trend in government
debt; iii) the efforts of the Serbian government
to repay the debt principal after the
fiscal rule breach have not been persistent,
providing empirical support to the fiscal fatigue
hypothesis; iv) the government budget
constraint has deteriorated since the beginning
of the global financial crisis; v) the response
of primary fiscal balance to public
debt from the onset of the global financial
crisis has dropped more severely in comparison
to other European economies
Experimental study on the stresses at the i-beam end-plate moment connection
The paper deals with experimental study of the stresses at the bolted end-plate moment connection. The design parameters are adopted to include prying effects in joint. A stress level is obtained in the elements where the highest values occur in the tension zone of the end-plate. The accompanied finite element analysis is performed for comparing purposes with experimental results. It is shown that end-plate thickness should be the unavoidable joint parameter in structural analysis of frame-like structures
Experimental study on the stresses at the i-beam end-plate moment connection
The paper deals with experimental study of the stresses at the bolted end-plate moment connection. The design parameters are adopted to include prying effects in joint. A stress level is obtained in the elements where the highest values occur in the tension zone of the end-plate. The accompanied finite element analysis is performed for comparing purposes with experimental results. It is shown that end-plate thickness should be the unavoidable joint parameter in structural analysis of frame-like structures
Experimental study on the stresses at the i-beam end-plate moment connection
The paper deals with experimental study of the stresses at the bolted end-plate moment connection. The design parameters are adopted to include prying effects in joint. A stress level is obtained in the elements where the highest values occur in the tension zone of the end-plate. The accompanied finite element analysis is performed for comparing purposes with experimental results. It is shown that end-plate thickness should be the unavoidable joint parameter in structural analysis of frame-like structures
Fiscal Reaction to Interest Payments-the Case of Serbia
We focus on the response of primary fiscal balance to interest
payments and borrowing costs on Serbian public debt before, during and in the aftermath of the global financial crisis. Our analysis reveals: i) policy makers financed up to 50% of each percentage point increase in interest payments to GDP ratio with new public debt issuance; ii) the government has responded to rising interest payments and borrowing costs by reducing primary fiscal balance from the onset of the global financial crisis; iii) the response of primary fiscal balance to interest payments mimics the response of primary fiscal balance to the costs of borrowing; iv) fiscal austerity measures adopted after the breach of fiscal rule for public debt have been insufficient to stabilize fiscal policy stance in Serbia
Oleinska kiselina - uticaj na zdravlje i status u fosfolipidima plazme u srpskoj populaciji
Oleic acid has many beneficial effects on human health. One of the main dietary sources of oleic acid is olive oil. Non-Mediterranean European countries, including Serbia, have low habitual olive oil consumption, but other vegetable oils also contain different amounts of oleic acid. In infants and young children m ilk is the most important source of fatty acids, including oleic acid. Furthermore, fatty acid composition of plasma phospholipids reflects dietary intake and fatty acid metabolism. In patients with serious chronic diseases fatty acid status is altered independently on the intake. Here we reviewed status of oleic acid in healthy persons as well as in patients with different chronic diseases in Serbia.Oleinska kiselina ima ima viÅ”estrukepozitivne efekte na život i zdravlje ljudi. Jedan od glavnih izvora oleinske kiseline je maslinovo ulje. Evropske zemlje, koje nepripadaju mediteranskoj regiji, meÄu kojima je i Srbija, retko koriste maslinovo ulje u ishrani, ali i druga biljna ulja sadrže oleinsku kiselinu u razliÄitom procentu. Kod odojÄadi i dece mlaÄeg uzrasta, mleko je najvažniji izvor masnih kiselina, ukljuÄujuÄi i oleinsku. Dijetetski unos masnih kiselina i njihov metabolizam u telu, odražava masnokiselinski sastav ufosfolipidima plazme. Kod pacijenata sa teÅ”kim hroniÄnim oboljenjima, masnokiselinski sastav je promenjen nezavisno od unosa. U ovom radu je prikazan status oleinske kiseline kod zdravih osoba, kao i kod pacijenata sa razliÄitim hroniÄnim oboljenjima u Srbiji
The effect of chronic intensive training on oxidativ stress parameters and fatty acid profiles of plasma and erythrocytes in female athletes
Intenzivna fiziÄka aktivnost utiÄe na metabolizam lipida i masnih kiselina (MK), dovodi do poveÄane potroÅ”nje kiseonika u miÅ”iÄima i drugim tkivima Å”to vodi poveÄanoj produkciji reaktivnih kiseoniÄnih vrsta i može uticati na funkciju imunog sistema. Uticaj hroniÄnog intenzivnog vežbanja na parametre oksidativnog stresa i masnokiselinski profil fosfolipida kod aktivnih sportistkinja nije dovoljno ispitivan. Zbog toga je ova studija imala za cilj da
ispita MK profil fosfolipida plazme i eritrocita, parametre oksidativnog stresa, aktivnost enzima antioksidativne zaÅ”tite, kao i aktivnost monocita kao dela imunog sistema, kod dve grupe aktivnih sportistkinja: vaterpolistkinja (n=15) i fudbalerki (n=19). Kontrolnu grupu (n=14) su Äinile zdrave devojke istih godina starosti koje se ne bave fiziÄkom aktivnoÅ”Äu.
Uprkos sliÄnom dijetarnom unosu, MK profil plazme pokazao je znatno veÄi udeo
stearinske, oleinske i mononezasiÄenih masnih kiselina (MUFA) i znaÄajno niži procenat ukupnih i n-6 polinezasiÄenih MK (PUFA) kod fudbalerki u odnosu na vaterpolo i kontrolnu grupu. Sa druge strane vaterpolistkinje su imale viÅ”u procentualnu zastupljenost palmitoleinske i arahidonske kiseline u odnosu na kontrolnu grupu. MK profil eritrocita pokazao je znaÄajno veÄi procenat oleinske kiseline i MUFA kod fudbalerki u odnosu na kontrolnu grupu, i smanjeni procenat stearinske kiseline uz viÅ”i udeo palmitinske i palmitoleinske kiseline kod vaterpolistkinja u odnosu na druge dve grupe. Obe grupe sportistkinja su imale znaÄajno niži procenat n-6 PUFA i ukupnih PUFA u poreÄenju sa
kontrolnom grupom. Procenjena aktivnost desaturaza i elongaza u eritrocitima takoÄe je promenjena kod sportistkinja.
Analiza parametara oksidativnog stresa pokazala je znaÄajno veÄi ukupni antioksidativni status u plazmi i veÄi stepen lipidne peroksidacije u eritrocitima kod sportistkinja u odnosu na kontrolnu grupu. Koncentracija H2O2 u plazmi bila je veÄa kod sportistkinja u odnosu na neaktivne žene, ali su fudbalerke imale viÅ”i nivo H2O2 i u odnosu na vaterpolistkinje. Sa druge strane, koncentracija O2
.- bila je najniža kod vaterpolistkinja a najviŔa kod fudbalerki,
znaÄajno viÅ”a i u odnosu na kontrolnu grupu. Koncentracija NO2
- u plazmi bila je znaÄajno viÅ”a kod fudbalerki u odnosu na kontrolnu grupu. Aktivnost enzima antioksidativne zaÅ”tite u eritrocitima razlikovala se izmeÄu sportistkinja i kontrolne grupe. Tako je aktivnost katalaze
kod sportistkinja bila znaÄajno viÅ”a u odnosu na kontrolnu grupu, dok se aktivnost glutationperoksidaze nije razlikovala izmeÄu ispitivanih grupa. Aktivnost superoksid-dismutaze bila je najviÅ”a kod vaterpolistkinja, i nije se znaÄajno razlikovala izmeÄu fudbalerki i kontrolne grupe. Analiza metaboliÄke aktivnosti mononuklearnih Äelija periferne krvi pokazala je veÄu
aktivnost mononuklearnih Äelija kod sportistkinja, dok se produkcija O2
.- i NO2- u mononuklearnim Äelijama nije razlikovala izmeÄu ispitivanih grupa.
NaÅ”i rezultati su pokazali da dugotrajna intenzivna fiziÄka aktivnost znaÄajno utiÄe namasnokiselinski profil fosfolipida plazme i eritrocita, parametre oksidativnog stresa, aktivnost enzima antioksidativne zaÅ”tite, menja aktivnost mononuklearnih Äelija periferne krvi ali ne utiÄe na produkciju O2
.- i NO2 - u mononuklearnim Äelijama. Zapažene razlike
izmeÄu grupa vaterpolistkinja i fudbalerki ukazuju da tip sporta igra znaÄajnu ulogu u promenama u metablizmu kod sportistkinja.Intensive physical activity affects metabolism of lipids and fatty acids (FA), increases
consumption of oxygen in muscles and other tissues that leads to increased production of
reactive oxygen species and can affect immune system. The effect of chronic intensive
exercise on parameters of oxidative stress and phospholipids FA composition in elite female
athletes has not been studied extensively so far. Thus the aim of this study was to investigate
FA profiles in plasma and erythrocytes phospholipids, parameters of oxidative stress,
activity of antioxidative enzyme system and activity of monocytes as a part of immune
system in two groups of active female athletes: water polo (n=15) and football (n=19)
players. The control group was composed of 14 apparently healthy age-matched sedentary
women. In spite of similar dietary patterns, plasma FA profile in the football players showed
significantly higher proportion of stearic acid, oleic acid and monounsaturated FA (MUFA),
and significantly lower proportion of total and n-6 polyunsaturated FA (PUFA) than the
water polo and control group. The water polo players had higher percentages of palmitoleic
acid and arachidonic acid than the control subjects. Erythrocyte FA profile differed among
groups. We found significantly higher proportion of oleic acid and MUFA in the football
group than in the controls, and decreased stearic acid and elevated palmitic and palmitoleic
acid in the water polo players than in the other two groups. Both groups of athletes had
significantly lower percentages of n-6 PUFA and total PUFA compared to the controls. The
estimated activities of elongase and desaturases in erythrocytes were also altered in the
athletes.
Analysis of oxidative stress parameters showed significantly higher plasma total antioxidant
status and higher lipid peroxidation in erythrocytes of the athletes than in the controls.
Concentration of H2O2 in plasma was higher in the athletes compared with sedentary
women, but also higher in football than in the water polo players. On the other hand, level of
O2
.- was the lowest in water polo players and the highest in the football group.
Concentrations of both O2
.- and NO2
- were significantly higher in the football than in the
control group. Catalase activity was significantly higher in the athletes that in sedentary
women, while glutation peroxidase activity was similar in all groups. Superoxide-dismutase
activity was higher in the water polo group than in the other two groups. Furthermore,
metabolic activity of peripheral blood mononuclear cells was higher in the athletes, and
production of O2
.- i NO2
- in mononuclear cells did not differ among the studied groups.
Our results have shown that long-term, intense physical training significantly affected FA
status of plasma and erythrocyte phospholipids, oxidative stress and antioxidant enzyme
activity in women. It also changes metabolic activity of mononuclear cells but not the
production of O2
.- i NO2
- in mononuclear cells. The observed differences between the water
polo and the football players suggest that the type of regular training may contribute to the
altered metabolism in athletes.
Key words: phospholipids, fatty acids, physical activity, water polo, football, female athlete
Uticaj hroniÄnog intenzivnog treninga na parametre oksidativnog stresa i masnokiselinski profil plazme i eritrocita kod sportistkinja
Intensive physical activity affects metabolism of lipids and fatty acids (FA), increases consumption of oxygen in muscles and other tissues that leads to increased production of reactive oxygen species and can affect immune system. The effect of chronic intensive exercise on parameters of oxidative stress and phospholipids FA composition in elite female athletes has not been studied extensively so far. Thus the aim of this study was to investigate FA profiles in plasma and erythrocytes phospholipids, parameters of oxidative stress, activity of antioxidative enzyme system and activity of monocytes as a part of immune system in two groups of active female athletes: water polo (n=15) and football (n=19) players. The control group was composed of 14 apparently healthy age-matched sedentary women. In spite of similar dietary patterns, plasma FA profile in the football players showed significantly higher proportion of stearic acid, oleic acid and monounsaturated FA (MUFA), and significantly lower proportion of total and n-6 polyunsaturated FA (PUFA) than the water polo and control group. The water polo players had higher percentages of palmitoleic acid and arachidonic acid than the control subjects. Erythrocyte FA profile differed among groups. We found significantly higher proportion of oleic acid and MUFA in the football group than in the controls, and decreased stearic acid and elevated palmitic and palmitoleic acid in the water polo players than in the other two groups. Both groups of athletes had significantly lower percentages of n-6 PUFA and total PUFA compared to the controls. The estimated activities of elongase and desaturases in erythrocytes were also altered in the athletes. Analysis of oxidative stress parameters showed significantly higher plasma total antioxidant status and higher lipid peroxidation in erythrocytes of the athletes than in the controls. Concentration of H2O2 in plasma was higher in the athletes compared with sedentary women, but also higher in football than in the water polo players. On the other hand, level of O2 .- was the lowest in water polo players and the highest in the football group. Concentrations of both O2 .- and NO2 - were significantly higher in the football than in the control group. Catalase activity was significantly higher in the athletes that in sedentary women, while glutation peroxidase activity was similar in all groups. Superoxide-dismutase activity was higher in the water polo group than in the other two groups. Furthermore, metabolic activity of peripheral blood mononuclear cells was higher in the athletes, and production of O2 .- i NO2 - in mononuclear cells did not differ among the studied groups. Our results have shown that long-term, intense physical training significantly affected FA status of plasma and erythrocyte phospholipids, oxidative stress and antioxidant enzyme activity in women. It also changes metabolic activity of mononuclear cells but not the production of O2 .- i NO2 - in mononuclear cells. The observed differences between the water polo and the football players suggest that the type of regular training may contribute to the altered metabolism in athletes. Key words: phospholipids, fatty acids, physical activity, water polo, football, female athletesIntenzivna fiziÄka aktivnost utiÄe na metabolizam lipida i masnih kiselina (MK), dovodi do poveÄane potroÅ”nje kiseonika u miÅ”iÄima i drugim tkivima Å”to vodi poveÄanoj produkciji reaktivnih kiseoniÄnih vrsta i može uticati na funkciju imunog sistema. Uticaj hroniÄnog intenzivnog vežbanja na parametre oksidativnog stresa i masnokiselinski profil fosfolipida kod aktivnih sportistkinja nije dovoljno ispitivan. Zbog toga je ova studija imala za cilj da ispita MK profil fosfolipida plazme i eritrocita, parametre oksidativnog stresa, aktivnost enzima antioksidativne zaÅ”tite, kao i aktivnost monocita kao dela imunog sistema, kod dve grupe aktivnih sportistkinja: vaterpolistkinja (n=15) i fudbalerki (n=19). Kontrolnu grupu (n=14) su Äinile zdrave devojke istih godina starosti koje se ne bave fiziÄkom aktivnoÅ”Äu. Uprkos sliÄnom dijetarnom unosu, MK profil plazme pokazao je znatno veÄi udeo stearinske, oleinske i mononezasiÄenih masnih kiselina (MUFA) i znaÄajno niži procenat ukupnih i n-6 polinezasiÄenih MK (PUFA) kod fudbalerki u odnosu na vaterpolo i kontrolnu grupu. Sa druge strane vaterpolistkinje su imale viÅ”u procentualnu zastupljenost palmitoleinske i arahidonske kiseline u odnosu na kontrolnu grupu. MK profil eritrocita pokazao je znaÄajno veÄi procenat oleinske kiseline i MUFA kod fudbalerki u odnosu na kontrolnu grupu, i smanjeni procenat stearinske kiseline uz viÅ”i udeo palmitinske i palmitoleinske kiseline kod vaterpolistkinja u odnosu na druge dve grupe. Obe grupe sportistkinja su imale znaÄajno niži procenat n-6 PUFA i ukupnih PUFA u poreÄenju sa kontrolnom grupom. Procenjena aktivnost desaturaza i elongaza u eritrocitima takoÄe je promenjena kod sportistkinja. Analiza parametara oksidativnog stresa pokazala je znaÄajno veÄi ukupni antioksidativni status u plazmi i veÄi stepen lipidne peroksidacije u eritrocitima kod sportistkinja u odnosu na kontrolnu grupu. Koncentracija H2O2 u plazmi bila je veÄa kod sportistkinja u odnosu na neaktivne žene, ali su fudbalerke imale viÅ”i nivo H2O2 i u odnosu na vaterpolistkinje. Sa druge strane, koncentracija O2 .- bila je najniža kod vaterpolistkinja a najviÅ”a kod fudbalerki, znaÄajno viÅ”a i u odnosu na kontrolnu grupu. Koncentracija NO2 - u plazmi bila je znaÄajno viÅ”a kod fudbalerki u odnosu na kontrolnu grupu. Aktivnost enzima antioksidativne zaÅ”tite u eritrocitima razlikovala se izmeÄu sportistkinja i kontrolne grupe. Tako je aktivnost katalaze kod sportistkinja bila znaÄajno viÅ”a u odnosu na kontrolnu grupu, dok se aktivnost glutationperoksidaze nije razlikovala izmeÄu ispitivanih grupa. Aktivnost superoksid-dismutaze bila je najviÅ”a kod vaterpolistkinja, i nije se znaÄajno razlikovala izmeÄu fudbalerki i kontrolne grupe. Analiza metaboliÄke aktivnosti mononuklearnih Äelija periferne krvi pokazala je veÄu aktivnost mononuklearnih Äelija kod sportistkinja, dok se produkcija O2 .- i NO2- u mononuklearnim Äelijama nije razlikovala izmeÄu ispitivanih grupa. NaÅ”i rezultati su pokazali da dugotrajna intenzivna fiziÄka aktivnost znaÄajno utiÄe namasnokiselinski profil fosfolipida plazme i eritrocita, parametre oksidativnog stresa, aktivnost enzima antioksidativne zaÅ”tite, menja aktivnost mononuklearnih Äelija periferne krvi ali ne utiÄe na produkciju O2 .- i NO2 - u mononuklearnim Äelijama. Zapažene razlike izmeÄu grupa vaterpolistkinja i fudbalerki ukazuju da tip sporta igra znaÄajnu ulogu u promenama u metablizmu kod sportistkinja
Analysis of the cause of the girth gear tooth fracture occurrence at the bucket wheel excavator
Premature damages and fractures of components and structures of bucket-wheel excavators at open-pit mine often occur in exploitation, caused either by inadequate design or insufficient knowledge of the material properties, welded joints and flaws in component production technology. The bucket-wheel excavator, TAKRAF SRs 2000 x 32/5.0 was employed on the excavation of barren soil for 5.000 h (a few weeks more than a year after the assembly) when the fracture of the tooth of the girth gear, which enables the circular motion of the upper structure of the bucket-wheel excavator, occurred. The gear was, according to the manufacturer's certificate, made of the cast steel GS 40 MnCrSi3 V. The paper presents calculations of the stress variations cycles' number for one tooth, as well as of the fracture mechanics parameters - the critical stress intensity factor and critical crack length. It was established that the fracture of the tooth occurred due to an initial crack existing in its base, which originated during the gear's manufacturing, i.e. due to the so-called "manufacturing-in defect"
Biological effect of pomegranate polyphenols on the components of metabolic syndrome: implications on oxidative stress
Nar (Punica granatum, L) je jedan od najstarijih jestivih plodova koji se koristi u prevenciji i leÄenju od davnina.
RazliÄiti delovi biljke, kao Å”to su plod, seme, kora i liÅ”Äe, sadrže bioaktivne sastojke za koje se navodi da poseduju
lekovita i terapeutska svojstva. MeÄumnogobrojnimbioaktivnimkomponentama u naru, polifenoli
predstavljaju najvažniju grupumolekula sa pozitivnimefektomna zdravlje. Hipoglikemijski, hipolipemijski,
hipotenzivni i anti-oksidativni efekat polifenola nara potvrÄen je u brojnimstudijama. Ovaj pregledni rad ima
za cilj da predstavi najnovija istraživanja o strukturi i bioloŔkoj aktivnosti komponenata nara i njihovompotencijalnom
korisnom efektu u terapiji bolesti povezanih sa metaboliÄkim sindromom.Pomegranate (Punica granatum, L) is one of the oldest edible fruits used in prevention and treatment. Various
parts of the plant, such as fruit, seeds, bark, and leaves, contain bioactive ingredients that possess medicinal
and therapeutic properties. Among the many bioactive components in pomegranate, polyphenols
are the most important group of molecules with a positive effect on health. The hypoglycemic, hypolipidemic,
hypotensive, and anti-oxidative effects of pomegranate polyphenols have been confirmed in numerous
studies. The aim of this review is to present the latest research on the structure and activity of
bioactive components of pomegranate and their potential beneficial effect in the treatment of diseases related
to metabolic syndrome
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