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Revitalizacija deponija pepela zasnivanjem biljnog pokrivača predstavlja postupak kojim se najbolje može umanjiti rizik za životnu sredinu i zdravlje ljudi. Uspostavljanje biljnog pokrivača, setvom zeljastih i sadnjom drvenastih vrsta biljaka, obezbeđuje fizičku i hemijsku stabilizaciju pepela, sprečava eroziju vetrom i smanjuje disperziju toksičnih hemijskih elemenata u životnu sredinu. Selekcija biljnih vrsta u tom smislu je važan faktor koji determiniše efikasnost postupka revitalizacije deponije. Istraživanja koja su predmet ove teze, sprovedena su na deponiji pepela termoelektrane ‘Nikola Tesla A’ u Obrenovcu (‘TENT A’), koja zauzima 382 ha plodnog obradivog zemljišta, na desnoj obali reke Save i to: na aktivnoj laguni (L0) u koju se mešavina pepela i vode (1:10) hidraulički doprema i na dve pasivne lagune, L1 starosti tri godine i L2 starosti jedanaest godina, na kojima se sprovodi proces privremenog-kratkotrajnog biološkog obnavljanja pasivnih laguna deponije. Cilj istraživanja bio je definisanje abiotičkih faktora koji limitiraju opstanak i rast biljaka biljaka na lagunama deponije pepela različite starosti, kao i ispitivanje ekofizioloških, biohemijskih i morfoloških karakteristika i proučavanje adaptivnog odgovora drvenastih vrsta biljaka na efekte multipnog stresa. Istraživanjima su obuhvaćene dve sađene vrste, tamariks (Tamarix tetrandra Pall.) i bagrem (Robinia pseudoacacia L.) i dve spontano kolonizovane vrste, bagrenac (Amorpha fruticosa L.) i bela topola (Populus alba L.), koje su na prostor deponije dospele sa okolnih staništa. Na osnovu dobijenih rezultata procenjen je njihov kapacitet za opstanak u uslovima deponije i potencijal za sadnju u svrhu revitalizacije ovakvih staništa. Utvrđeno je da limitirajuće faktore za opstanak i rast biljaka na deponiji pepela ‘TENT A’, predstavljaju nepovoljne fizičke i hemijke karakteristike pepela (peskovit mehanički sastav koji uslovljava mali sadržaj vode dostupne biljkama, fina tekstura i obrazovanje cementnih slojeva koji ometaju ukorenjavanje biljaka, povišen salinitet i alkalnost, toksičnost As, B, Cu, Mo, Se, Cr i Ni i deficit C, N, P, Mn i Zn). Deponovanje pepela u vlažnim lagunama i njegova izloženost atmosferskim prilikama (weathered ash), njegova biorekultivacija i spontano naseljavanje biljaka, pozitivno su se odrazili na promenu početnih, veoma nepovoljnih fizičkih i hemijskih karakteristika... The revitalisation of fly ash deposits through the formation of a plant cover is a practice which can best reduce the risk to the environment and human health. Establishing a plant cover through sowing herbaceous plants and planting woody species ensures the physical and chemical stabilisation of the ash, prevents wind erosion, and reduces the dispersal of toxic, chemical elements into the environment. The choice of plant species for this purpose is an important factor which determines how effective the revitalisation of the ash deposit site will be. The research that is the subject of this study was carried out at the fly ash deposits at the 'Nikola Tesla A' thermoelectric power plant in Obrenovac ('TENT A'), which covers an area of 382 ha of fertile cultivated land on the right bank of the River Sava. More specifically, it focussed on an active lagoon (L0), into which a pulp of ash and water (1:10) is sluiced, and two passive lagoons - L1, weathered for three years, and L2, weathered for 11 years, where the process of the temporary, short-term biological restoration of these inactive ash deposit lagoons is being carried out. The aim of the research was to define the abiotic factors which limit the survival and growth of plants at fly ash deposit lagoons weathered for different lengths of time, as well as to investigate ecophysiological, biochemical and morphological characteristics, and to study the adaptive responses of woody plant species to the effects of multiple stress. The study focussed on two planted species, tamarisk (Tamarix tetrandra Pall.) and black locust (Robinia pseudoacacia L.) and two naturally colonized species false indigo (Amorpha fruticosa L.) and white poplar (Populus alba L.), which colonized the ash deposit sites from surrounding habitats. On the basis of the results obtained, these species’ capacity for survival in the conditions encountered at a fly ash deposit site and their potential for being planted with the aim of revitalising this type of habitat were assessed. It was established that the limiting factors for plant survival and growth at the ‘TENT A’ fly ash deposits were the unfavourable physical and chemical characteristics of the ash (its sandy composition which results in a low water content available to plants; its fine texture and the formation of cemented layers in the ash that hinder the rooting of plants; increased salinity and alkalinity; As, B, Cu, Mo, Se, Cr and Ni toxicity; and C, N, P, Mn and Zn deficiency)...

The focus in the present thesis lies with the synchronization mediated self-organization phenomena in populations of globally coupled stochastic excitable or bursting units subjected to interaction delays. Excitable local dynamics follows the Fitzhugh- Nagumo model, canonical for type II excitability, whereas the bursting units are represented by the Hindmarsh-Rose model. The study comprises two complementary lines of research. One is aimed at extending the analogy regarding the complex forms of collective behavior exhibited by the assemblies of coupled nonlinear autonomous oscillators and those made up of excitable units. Within the second line of research, our main contribution consists in developing the mean-field based models for the collective dynamics of the assemblies of excitable or bursting units, whose microscopic dynamics is governed by large sets of coupled stochastic delay-differential equations. This is instigated by the notion that any population displaying a collective mode may be treated as macroscopic oscillator. While the framework itself rests on implementing the cumulant approach complemented by the Gaussian approximation, one of the principal gains presents the ability to recast the problem of (stochastic) bifurcations affecting the stability of the stationary state of the exact system in terms of flows containing only several deterministic delaydifferential equations, where noise intensity may act as a bifurcation parameter...

This thesis is devoted to the study the synthesis, structure and magnetic properties of yttrium cuprate and yttrium manganite. The structure of the samples was investigated by x-ray diffraction (XRD). Investigation of structural parameters was performed by the Rietveld full-profile analysis method with the application of the FULLPROF software package and the magnetic properties were investigated by magnetization measurement using SQUID magnetometer. For the first time, two alternative synthesis routes for Y2Cu2O5 have been successfully applied, based on precursors obtained by glycine-nitrate and self-propagating high-temperature synthesis (SHS) combustion reactions. Both applied methods proved to be far superior over the standard ceramic sintering, with one of them (SHS) resulting in the reduction of overall synthesis time from 10 days to only 12 hours. The structure and magnetic characterization of obtained samples has shed some new light phenomenon of copper ion drift within the unit cell. It is demonstrated that differences in magnetic behavior can be directly correlated to the variable degree of copper displacement which, besides the phase purity, represents an additional important factor that has to be considered in the course of Y2Cu2O5 preparation. This work also represents the first study of the influence of magnetic dilution on low-temperature magnetic properties of Y2Cu2O5. Partial Mg substitution for Cu was found to introduce small but detectable distortions in the two main intradimmer superexchange paths so that ferromagnetic correlations decrease with Mg concentration. More significant impact of Cu substitution was found in the low temperature region due to the breaking of infinite Cu-O chains. The formation of finite size chains introduces significant paramagnetic contribution and reduction in Néel temperature. Despite this, overall results give a strong indication that antiferromagnetic ordering as well as metamagnetism persists up to the 15% of the Mg content. The second part of the thesis deals with possibilities to apply the SHS combustion in preparation of nanoparticle hexagonal YMnO3, and with the investigation of size reduction influence on its magnetic properties. In two different experimental setups, samples with particle size down to 20 nm were successfully obtained, with the variable... Doktorska disertacija posvećena je proučavanju sinteze, strukture i magnetnih osobina kuprata i manganita itrijuma. Kristalna struktura uzoraka ispitivana je rendgenskom difrakcijom (XRD). Određivanje strukturnih parametara je urađeno pomoćue Ritveldove pune profilne metode uz primenu softverskog paketa FULLPROF. Magnetne osobine ispitivane su merenjem magnetizacije pomoću SQUID magnetometra. Dve nove, alternativne metode sinteze sagorevanjem, na bazi prekursora dobijenih glicin-nitratnom metodom i samorasprostirućim talasom sagorevanja (SHS), prvi put su uspešno primenjene za sintezu itrijum-kuprata Y2Cu2O5 i opisane u ovom radu. Obe metode pokazale su se kao daleko superiornije u odnosu na standardni postupak keramičko sinterovanja, pri čemu je jedna od njih (SHS) dovela do redukcije ukupnog vremena sinteze sa prosečnih 10 dana sinterovanja na svega 12 sati. Karakterizacija kristalne strukture i magnetnih osobina ukazale su na veliki značaj termalno drifta bakarnih jona, koji se može doves i u direktnu vezu sa ra likama u ponašanju uzoraka dobijenih različitim termalnim tretmanom. Pokazano je da da se, pored fazne čistoće, i stepen termalnog drifta jona bakra takođe mora uzeti u obzir kao važan dodatni faktor prilikom sinteze itrijum-kuprata...

U disertaciji su prikazana šumska zemljišta Javor planine u Republici Srpskoj, a na bazi terenskih i laboratorijskih istraživanja osnovnih fizičkih i hemijskih osobina. Planina Javor se nalazi u istočnom dijelu Republike Srpske izmeñu opština Vlasenica, Han Pijesak i Kladanj (Federacija BiH). Pravac pružanja masiva Javor jeste sjeverozapad – jugoistok, a najveći vrh je Veliki Žep 1537 mn.v. Geološki je heterogeno, centralnim dijelom dominiraju krečnjaci, južne i jugozapadne padine pokrivaju pješčari, rožnjaci i glinci, sjeverne i sjeveroistočne krečnjaci – rožnjaci. Lokalno ima laporaca, jezerskih sedimenata i peridotita. Područje ima obilježja planinske klime sa kontinentalnim uticajem. Vrijednost srednje godišnje temperature na donjoj granici rasprostranjenja iznosi 6,2°C, a na gornjoj granici visinskog pojasa 3,8°C. U vegetacionom periodu padne prosječno 583 mm odnosno 57,7%. Prema veličini godišnjeg klimatskog indeksa dominira jako humidna klima, sa povećanjem visine postaje perhumidna. Najveći dio masiva Javor pokrivaju šume bukve i jele sa smrčom (Piceo – Abieti – Fagetum, Stef., et al. 1983). Izdvojeni su sledeći tipovi zemljišta: crnica, ranker, eutrično smeñe zemljište, kiselo smeñe zemljište, smeñe zemljište na krečnjaku, podzol, brunipodzol i ilimerizovano zemljište. Najrasprostranjeniji tipovi zemljišta na krečnjacima crnica i smeñe zemljište. Crnice su dobro razvijene, varijabilne dubine, struktuirane i humozne. Na grebenima, strmim padinama veoma su ugrožene od erozije. Smeñe krečnjačko zemljište je srednje duboko, najčešće dobro obezbijeñeno humusom, a produktivnost mu je odreñena dubinom, stepenom stjenovitosti i kamenitosti. Kiselo smeñe zemljište je dominantan tip zemljišta na silikatima Javora. Ovo je uglavnom srednje duboko do duboko zemljište. Humus je tipa moder. Ilovasta tekstura uz stabilnu sferoidnu strukturu obezbijeñuju povoljan vodno – vazdušni režim. Eutrični kambisol je lokalno rasprostranjen, srednje dubok, humozan. Tekstura mu varira u zavisnosti od supstrata. Podzoli se javljaju lokalno u Partizan polju. Ovo je duboko, pjeskovito i veoma siromašno zemljište. Brunipodzoli se razvijaju u uslovima manje kiselosti supstrata i manje su siromašni od podzola. Ilimerizovano zemljište je razvijeno na krečnjačkoj i silikatnoj podlozi... This dissertation presents forest soils of Javor Mountain in the Republic of Srpska, based on field and laboratory research of basic physical and hemical characteristics. Javor mountain is located in east part of the Republic of Srpske, between municipalities Vlasenica, Han Pijesak and Kladanj (Federation of Bosnia and Herzegovina). Geographical direction of massif is northwest - southeast, and the highest peak is 1537 meters above sea namely Veliki Žep. Geologicaly is heterogeneous, the central part is covered by limestones, southern and southwestern slopes covers sandstones, cherts and claystones, north and northeast slopes are covered with limestones and cherts. Localy we found marl, lake sediments and peridotite. The area has mountain climate with continental influences. Average value of annual temperature at the lowest level of mountain is 6.2°C, and the highest point has 3.8°C. In vegetation period average precipitation is 583 mm or 57.7%. According to the size of the annual climate index, very humid climate dominated and with higher altutide becomes perhumid. The biggest surface of Javor Mountain is covered by beech fir and spruce forests (Piceo - Abieti - Fagetum, Stef., et al. 1983). The following types of soil are separated: ranker, black soil, eutric brown soil, dystric brown soil, brown soil, podzol, brown podzolized soil and illimerized soil. The most prevalent soil type on limestones are black soil and brown soil. Black soils are well developed, with variable depth, well structured, humic, with a high adsorptive complex. On the ridges, steep slopes black soils are highly endangered by erosion. Brown soil on limestone is moderately deep, mostly with moderate humus level, and productivity is determined by their depth and degree of rockiness and stouniness. Acid brown soil is the dominant soil type on silicates of Javor Mountain. These are mainly moderately to very deep soils. Humus is moder type. Loam texture with a stable spheroidal structure provides advantageous water - air regime. Eutric brown soil is developed on small parts of mountain. Texture depends of character of substrate. Podzols are connected with specific acidophilic conditions in small parts of Partizan field. Brown podzolic soils are developed in condition of lower substrate acidity and they are not as poor as podzols are....

Свакодневно увећавање светског становништва чија потреба за производњом хране и местом за становање непрестано расте и захтева проширивање територије најчешће на рачун крчења шума, доводи до деградације животне средине у свим сегментима. Голети настале обешумљавањем су веома еродибилна станишта чему доприноси одсуство влаге, изражена купираност терена са великим нагибима, геолошка подлога, неповољна хидрографска мрежа и начин коришћења земљишта као један од значајних фактора деградације. Пошумљавање је метода успостављања шумске вегетације на обешумљеним подручјима чиме се земљиште успешно и дугорочно штити од деградације и притом се обезбеђују вишеструке користи које се могу исказати мелиоративним ефектима пошумљавања. Мелиоративни ефекти противерозионих пошумљавања су исказани вредновањем утицаја на процес педогенезе кроз анализу физичких и хемијских особина земљишта. Обогаћивање биодиверзитета је вредновано анализом односа флористичког састава и одређених фактора средине... Every day, the world's population with increasing need for food production and housing is growing and tending to expand territory in account of deforestation, which leads to the degradation of the environment in all aspects. Bare lands occur as а result of deforestation. Such habitats are highly erodable thanks to the lack of moisture, steep slopes, bedrock, unfavorable hydrographic network and land use as one of the main factors of degradation. Afforestation is a method of establishing forest vegetation on deforested land areas to provide longterm degradation protection and thereby achieve the multiple benefits that can be expressed by ameliorative effects of afforestation. Ameliorative effects of afforestation are presented by evaluation of the impact of afforestation on the process of pedogenesis through analysis of the physical and chemical properties of soil. Enrichment of biodiversity is evaluated by analyzing the relationship of the floristic composition and certain environmental factors. Effect in erosion control is evaluated by estimation of soil loss according to Gavrilovic, in years 1967. and 2009...

Bukva je jedna od najvažnijih vrsta drveća u Srbiji, s obzirom na njenu prostornu zastupljenost i učešće u ukupnoj drvnoj zapremini. Očekivane klimatske promene, koje će se u umereno-kontinentalnoj klimatskoj zoni manifestovati kroz intenziviranje i trajanje suša tokom vegetacionog perioda, imaće negativan uticaj na bukvu, koja je poznata kao vrsta osetljiva na sušu. Danas je gotovo izvesno da će učestale letnje suše voditi ka povećanoj ugroženosti pojedinih ekosistema bukve unutar postojećeg areala, pri čemu pojedine procene idu čak dotle da predviđaju da će usled ovakvih promena doći do redukcije prirodnog areala vrste u pojedinim krajevima. Kao najugroženija područja smatraju se regioni južne i jugo-istočne Evrope, kao i staništa na nižim nadmorskim visinama. Kako bi se uradila procena budućeg areala bukve u sklopu globalnih klimatskih promena i sagledala sposobnosti populacija da se prilagode izmenjenim stanišnim uslovima, u okviru COST akcije E52: "Evaluation of beech genetic resources for sustainable forestry", osnovano je više provenijeničnih testova u više zemalja Evrope. Kako je Srbija bila učesnik navedenog programa to je na njenoj teritoriji, u 2007. godini, osnovano dva provenijenična testa. Jedan je osnovan na teritoriji Nacionalnog parka "Fruška gora", dok je drugi osnovan u okviru Naučno-nastavne baze Šumarskog fakulteta Univerziteta u Beogradu "Majdanpečka Domena", u Debelom Lugu. Istraživanja sprovedena u okviru doktorske disertacije su bila usmerena na ispitivanje varijabilnosti pojedinih anatomskih, fizioloških i morfoloških parametara u provenijeničnim testovima bukve osnovanim na teritoriji Republike Srbije. Istraživanje je sprovedeno tokom 2010. i 2011. godine i obuhvatilo je ukupno 21 provenijenciju, koje su bile zajedničke za oba lokaliteta. Rezultati istraživanja su pokazali da je postojala značajna genetička varijabilnost kako unutar, tako i između različitih provenijencija, kao i da su rezultati merenja bili pod uticajem kako genetičke konstitucije provenijencija, tako i stanišnih uslova lokaliteta na kojima su testovi osnovani... Climate is considered to be the main factor that determines forest species distribution. In Serbia, climatic series show a global warming trend and an increase in frequency of summer droughts, which should affect growth and regeneration of tree populations. European beech is one of the major tree species in Serbia, considering its large spatial distribution and involment in total wood volume. Beech is particularly sensitive to drought and high temperatures. In the temperate-continental zone, it is almost certain, based on climate scenarios, that the frequent summer droughts will lead to increasement of vulnerability to some European beech ecosystems within the current range. Changes in climate not only will increase vulnerability of the beech ecosystems but also will reduce natural range of this particular species in some areas. The most endangered areas are considered the regions of South and South-East Europe, as well as stands at the lower altitudes. In order to make predictions of the future distribution range of beech forest ecosystems and insight into the ability of provenances to adapt to the different site conditions, several provenance trials, in five European countries were founded as a final product within COST Action E52: "Evaluation of Beech Genetic Resources for Sustainable Forestry". As a participant of the above mentioned program, two provenance trials were established in 2007 in the Republic of Serbia. One of the trials is situated on the territory of National park "Fruška Gora", while the second one is located on the territory of the Scientific Centre of the University of Belgrade, Faculty of Forestry – "Majdanpečka Domena", in Debeli Lug. Research conducted in this doctoral dissertation was focused on the investigation of variability of anatomical, physiological and morphological parameters of European beech provenances, in two Serbian provenance trials. Study was conducted in 2010 and 2011, and involved 21 provenance in total, which were common for both of the trials. The results showed the significant genetic variation within and between different provenances, and that the measurement results were influenced by genetic constitution of the provenance, as well as site conditions..

Hronični venski ulkus spada u najmasovnija oboljenja čovečanstva i predstavlja jednu od najtežih komplikacija hronične venske insuficijencije. Lečenje ulkusne bolesti spada u najkompleksnija lečenja uopšte i često je skopčano sa veoma neizvesnim uspehom. Preko 30 % pacijenata sa hroničnim venskim ulkusom se leči duže od 20 godina a oko 10 % pacijenata duže od 30 godina. Ulkus kruris čini između 57% i 80 % svih hroničnih ulceracija. Jedan venski ulkus kruris, koji pod optimalnom flebološkom terapijom ne pokazuje tendenciju zarastanja ili koji u toku 12 meseci nije zarastao, smatra se rezistentnim na terapiju. Procenjuje se da u odrasloj populaciji Srbije od hroničnog venskog ulkusa boluje 1,5 do 2,5 %, što ima veliki socialno-ekonomski značaj. U lečenju HVU stadijuma C 5-6 primenjuju se brojne metode kako konzervativne tako i operativne, shodno etiologiji i lokalnom nalazu ali postoji velika stopa recidiva kao i rezistentnost na brojne metode lečenja. Cilj disertacije je da se kroz poređenje klasičnih metoda lečenja hroničnog venskog ulkusa (HVU) bez primene subkutane paratibijalne fasciotomije (SPTF) sa klasičnim metodama lečenja HVU uz primenu SPTF, odredi značaj subkutane paratibijalne fasciotomije za lečenje HVU. U istraživanje je uključeno ukupno 100 bolesnika kod kojih je lečenje hroničnog venskog ulkusa sprovedeno klasičnim metodama lečenja tog obolenja . Prvu grupu je sačinjavalo 50 bolesnika kod kojih je klasično lečenje sprovedeno uz dodatnu primenu subkutane paratibijalne fasciotomije, a drugu grupu 50 bolesnika kod kojih je klasično lečenje sprovedeno bez primene subkutane paratibijalne fasciotomije. Perioperativno i postoperativno su kod svih praćeni prethodno postavljeni parametri, klinički tok , pojava komplikacija lečenja HVU, kao i dužina zarastanja HVU, pritisci u mišićnim odeljcima potkolenice sa ulkusom kao i vrednosti transkutanog pritiska kiseonika potkolenice sa ulkusom. Dobijeni rezultati su uz klinički aspekt, potvrdili da kod bolesnika kod kojih je klasično lečenje hroničnog venskog ulkusa sprovedeno uz primenu subkutane paratibijalne fasciotomije, dolazi do bržeg zarastanja ulkusa, da je manja stopa recidiva i da subkutana paratibijalna fasciotomija dovodi do značajnog pada pritiska u mišićnim kompartmentima i porasta transkutanog parcijalnog pritiska kiseonika. Ova studija je pokazala da je primena SPTF u lečenju HVU sigurna, pouzdana i efikasna procedura koja nije praćena komplikacijama kako intraoperativnio, tako ni postoperativno. Primena SPTF ubrzava zatvaranje ulkusa, smanjuje stopu recidiva i omogućava poboljšanje lokalne mikrocirkulacije u pogođenoj regiji čime se rešava jedan od brojnih faktora smetnje zarastanja ulkusa-hronična ishemija usled hroničnog fasciokompresivnog sindroma, popravlja se mikrocirkulacija u pogođenoj regiji, što sve ukupno povoljno utiče na njegovo zarastanje. Sam operativni akt je bezbedan, ne zahteva posebnu aparaturu niti specijalnu obuku hirurškog tima, te kao takav je primenjiv kod najvećeg broja pacijenata sa ulkus krurisom koji su kandidati za operativno lečenje. Chronic venous ulcer is one of the most widespread diseases of mankind and is one of the most serious complications of chronic venous insufficiency. Treatment of venous ulcer is one of the most complex treatment in general and is often coupled with very uncertain success. Over 30% of patients with chronic venous ulcer is treated with more than 20 years and about 10% of patients over 30 years. Venous ulcer makes between 57% and 80% of all chronic ulcers. A venous ulcer cruris, which under optimal therapy shows no tendency to heal or for 12 months is not healed, it is resistant to therapy. It is estimated that in the adult population of Serbia with chronic venous ulceration affects 1.5 to 2.5%, which is of great socio-economic importance. In the treatment of stage C 5-6 venous ulcer, there are numerous methods of conservative and operative, according to the etiology and local findings, but there is a high recurrence rate and resistance to a number of methods of treatment. The aim of the dissertation is to compare the conventional methods of treatment of chronic venous ulcers without the use of subcutaneous paratibial fasciotomy (SPTF) with conventional methods of treatment, using SPTF, determine the importance of subcutaneous paratibial fasciotomy for the treatment of chronic venous ulcer. The study included a total of 100 patients the treatment of chronic venous ulcers conducted by classical methods of treatment of this disease. The first group consisted of 50 patients in whom conventional treatment was conducted with the additional use of subcutaneous paratibial fasciotomy, a second group of 50 patients in whom conventional treatment is conducted without the use of subcutaneous paratibial fasciotomy. Perioperative and postoperative were monitored in all pre-set parameters, clinical course, occurrence of complications of treatment chronic venous ulcer and chronic venous ulcer healing length, the pressure in muscle compartments of the lower leg with ulcers as well as the value of transcutaneous oxygen pressure with a lower leg ulcer. The results obtained with the clinical aspect, confirmed that in patients in whom conventional treatment of chronic venous ulcers conducted with the use of subcutaneous paratibial fasciotomy, coming in faster healing of ulcers, the lower recurrence rate and subcutaneous paratibial fasciotomy leads to a significant drop in pressure in the muscle compartments and an increase in transcutaneous partial pressure of oxygen. This study has shown that the use SPTF for the treatment of chronic venous ulcers secure, reliable and effective procedure that is not accompanied by complications that intraoperatively, nor postoperatively. Application SPTF accelerates ulcer closure, reduces relapse rate and to improve local microcirculation in the affected region, which solves one of the many factors interfere ulcer-healing chronic ischemia due to chronic fasciokompresywe syndrome, improves the microcirculation in the affected region, the total of all its positive effect on healing . I act is operating safely, without any special apparatus or special training of the surgical team, and as such is applicable in most patients with chronic venous ulcer who are candidates for surgical treatment .

Nucleus accumbens is a part of the ventral striatum also known as a drug active brain region, especially related with drug addiction. The aim of the study was to investigate the Golgi morphology of the nucleus accumbens neurons. The study was performed on the frontal and sagittal sections of 15 human brains by the Golgi Kopsch method. We classified neurons in the human nucleus accumbens according to their morphology and size into four types: type I – fusiform neurons; type II – fusiform neurons with lateral dendrite, arising from a part of the cell body; type III – pyramidal-like neuron; type IV – multipolar neuron. The medium spiny neurons, which are mostly noted regarding to the drug addictive conditions of the brain, correspond to the type IV – multipolar neurons. Two regions of human nucleus accumbens could be clearly recognized on Nissl and Golgi preparations each containing different predominant neuronal types. Central part of nucleus accumbens, core region, has a low density of impregnated neurons with predominant type III, pyramidal-like neurons, with spines on secondary branches and rare type IV, multipolar neurons. Contrary to the core, peripheral region, shell of nucleus, has a high density of impregnated neurons predominantly contained of type I and type IV – multipolar neurons, which all are rich in spines on secondary and tertiary dendritic branches. Our results indicate great morphological variability of human nucleus accumbens neurons.

Pomocu numerickih simulacija, proucavana je dinamika kompaktifikacije ansambla frikcionih diskova koji su podvrgnuti vertikalnim vibracijama. Vibracione pobude granularnog materijala su modelovane kao niz sukcesivnih vertikalnih dilatacija pakovanja diskova, koje su pracene dinamickom rekompresijom skupine diskova pod uticajem gravitacije. Druga faza vibracione pobude je bazirana na efikasnom molekularno-dinamilkom algoritmu hladenja granularnog gasa. Dinamika kompaktifikacije je proucavana za razne vrednosti koeficijenta trenja i koeficijenta normalne restitucije. Pokazano je da se vremenska evolucija gustine odigrava po zakonu , gde je Mittag-Leffler-ova funkcija reda . Parametar opada sa porastom intenziteta vibracione pobude . Promene strukture unutar granularnog pakovanja tokom procesa kompaktifikacije kvantitativno su opisane korišcenjem Vorono-eve teselacije. Analiziom distribucije faktora oblika Vorono-evih poligona dat je uvid u prisustvo i transformacije domena razlicite uredenosti unutar granularnog pakovanja. Pokazano je da je sužavanje distribucije verovatnoce faktora oblika u saglasnosti sa cinjenicom da se monodisperzna pakovanja diskova spontano organizuju u oblasti sa kristalnim uredenjem. Osim toga, organizacija granula na lokalnom nivou proucavana je pomocu analize vremenske evolucije brojeva povezanosti (koneksnosti) i distribucije pora (šupljina). U slucaju dvodimenzionalnog granularnog sistema metalnih diskova eksperimentalno su izucavane distribucije faktora oblika i poredene sa rezultatima simulacija. Memorijski efekti koji se ispoljavaju prilikom nagle promene intenziteta vibracija interpretirani su na osnovu analize vremenske evolucije brojeva povezanosti, distribucije pora i faktora oblika. Izgraden je model kompaktifikacije zasnovan na specificnim svojstvima stohastickih procesa frakcionog tipa koji adekvatno odslikavaju mikrostrukturalne transformacije granularnog pakovanja tokom procesa vibracione kompaktifikacije. U modelu se pretpostavlja da postoje samo dve moguce orjentacije granula. Orjentacijom je odreden slobodni prostor (šupljina) koji granula generiše u svom neposrednom okruženju. Imajuci za cilj jednostavnu imitaciju procesa kompaktifikacije granularnog materijala pod uticajem slabe eksterne pobude, pretpostavlja se da je prebacivanje granula iz jednog stanja orjentacije u drugo moguce opisati pogodno izabranim stohastickim procesom. Zapravo, interakcija granula sa okolnim granulama je stohasticki proces i ona je formalno inkorporirana u model kroz metod subordinacije stohastickih procesa u vremenu. Osnovna fizicka ideja tog pristupa je da vremenske intervale izmedu uzastopnih preorjentacija objekata u modelu odreduje pogodno izabrana distribucija vremena cekanja . Izborom ovog stohastickog procesa obezbeduje se neophodno svojstvo modela da reprodukuje sporu dinamiku kompaktifikacije i memorijske efekte. Iako je model dovoljno jednostavan da dozvoljava analiticki tretman, teorijski rezultati su potkrepljeni numerickim simulacijama odgovarajucih stohastickih procesa frakcionog tipa. Kinetika procesa depozicije dimera na jednodimenzionalnoj rešetki u prisustvu desorpcije je proucavana Monte-Carlo simulacijama. Osnovni cilj je bio istražiti kako razne vremenske zavisnosti verovatnoce ubrzavaju, ili usporavaju, porast gustine tokom procesa reverzibilne depozicije. Analiziran je rast pokrivenosti iznad granice zagušenja , ka stacionarnoj vrednosti , u slucajevima kada se verovatnoca desorpcije smanjuje skokovito i linearno (kontinualno) u odredenom vremenskom intervalu. Numericki je potvrdeno da se vreme koje je potrebno sistemu da dostigne zadatu gustinu može znacajno redukovati ukoliko se smanjuje u toku vremena. Razvijen je i analiziran samousaglašeni protokol optimizacije procesa depozicije u kome se optimalna vrednost verovatnoce desorpcije u nekom trenutku odreduje na osnovu trenuto dostignute vrednosti gustine . Dobijeni rezultati sugerišu da se proces vibracione kompaktifikacije može optimizovati korišcenjem vremenski zavisnog intenziteta spoljašnje pobude. Compaction dynamics of frictional hard disks subjected to vertical shaking is studied by numerical simulation in two dimensions. Shaking is modeled by a series of vertical expansion of the disk packing, followed by dynamical recompression of the assembly under the action of gravity. The second phase of the shake cycle is based on an efficient event-driven molecular-dynamics algorithm of cooling. The compaction dynamics is analized for various values of friction coefficient and coefficient of normal restitution. It was shown that the time evolution of the density is described by , where denotes the Mittag-Leffler function of order . The parameter is found to decay with tapping intensity . Vorono tessellation and a certain shape factor, which is a clear indicator of the presence of different domains in the packing, were used to quantify the changes in the internal structure of packing during the compaction. It was found that the narrowing of the probability distribution of the shape factor during the compaction is in accordance with the fact that the packings of monodisperse hard disks spontaneously assemble into regions of local crystalline order. In addition, the local organization of disks is characterized in terms of contact connectivity and distribution of the Delaunay ‘free’ volumes. The distributions of the shape factor in a 2D granular system of metallic disks were investigated experimentally and compared with the simulation results. An interpretation of the memory effects observed for a discontinuous shift in tapping intensity is provided by the analysis of the time evolution of connectivity numbers, volume distribution of pores and distribution of shape-factor. The simple model of granular compaction based on subordination of stochastic processes is presented. In order to imitate, in a very simplified way, the compaction dynamics of granular material under tapping, it is imposed that particles switch stochastically between the two possible orientational states characterizing the average volumes of the grain in the presence of other grains. The main physical idea of approach is that the interaction of grains with their environment is taken into account with the aid of the temporal subordination. Accordingly, it is assumed that the time intervals between the consecutive grain’s reorientations are governed by a certain waiting-time distribution . It is demonstrated how the presence of the trapping events leads to the macroscopic observation of slow compaction dynamics, described by an exact fractional kinetic equation. Numerical simulations are performed to examine our analytical result. In addition, memory effects are reproduced numerically by considering the response of the system to the abrupt change in the external excitation. Kinetics of the deposition process of dimers in the presence of desorption is studied by Monte-Carlo method on a one-dimensional lattice. The aim is to investigate how do various temporal dependences of the desorption rate hasten or slow down the deposition process. The growth of the coverage above the jamming limit to its steady-state value is analyzed when the desorption probability decreases both stepwise and linearly (continuously) over a certain time domain. It is reported a numerical evidence that the time needed for a system to reach the given coverage can be significantly reduced if decreases in time. Finally, a self-consistent optimization procedure, when the probability depends on the current coverage density , is formulated and tested. The present model reproduces qualitatively the densification kinetics and the memory effects of vibrated granular materials. The obtained results suggest that the process of vibratory compaction of granular materials can be optimized by using a time dependent intensity of external excitations