Nanocomplexes of polymers and surfactant in drug delivery

Istraženi su nanokompleksi anionskoga biopolimera, karagena i kationske površinski aktivne tvari za primjenu u terapijskim sustavima. Struktura i veličina kompleksa od nano- do mikrodimenzija ovise o koncentraciji i omjeru koncentracija pojedinih komponenata, te linearnoj gustoći naboja na lancu karagena. Faktori o kojima ovisi kompleksiranje jesu elektrostatska i hidrofobna međudjelovanja, te konformacija karagena. Porastom koncentracije karagena, unutar-makromolekulski kompleksi prelaze u među-makromolekulske, koji se postupno reorganiziraju u uređenije strukture, divovske vezikule, talog - dodecilamonijev karagenat i gel. Nastajanje divovskih vezikula i strukturna svojstva netopljivih kompleksa i urušenoga gela pokazuju daje lamelno uređenje stuktuma značajka kompleksa karagena i kationske površinski akivne tvari.Nanocomplexes formed from anionic biopolymers, carrageenans, and cationic surfactant have been investigated for their applicability in drug delivery. Stucture and complex size from nano- to microdimension strongly depends on concentration and concentration ratio of both components and linear charge density on carrageenan chains. Factors governing the complex formation are electrostatic and hydrophobic interactions as well as conformation of the carrageenan chains. With increasing carrageenan concentration, the intra-macromolecular complexes change to inter-macromolecular, which subsequently reorganize into bettei ordered structures, giant vesicles, precipitate - dodecylammonium carrageenate and gels. Formation of giant vesicles and structural properties of insoluble complexes and collapsed gels revealed lamellar ordering as an important feature of the carrageenan and an oppositely charged surfactant complexes

Nanocomplexes of polymers and surfactant in drug delivery

Istraženi su nanokompleksi anionskoga biopolimera, karagena i kationske površinski aktivne tvari za primjenu u terapijskim sustavima. Struktura i veličina kompleksa od nano- do mikrodimenzija ovise o koncentraciji i omjeru koncentracija pojedinih komponenata, te linearnoj gustoći naboja na lancu karagena. Faktori o kojima ovisi kompleksiranje jesu elektrostatska i hidrofobna međudjelovanja, te konformacija karagena. Porastom koncentracije karagena, unutar-makromolekulski kompleksi prelaze u među-makromolekulske, koji se postupno reorganiziraju u uređenije strukture, divovske vezikule, talog - dodecilamonijev karagenat i gel. Nastajanje divovskih vezikula i strukturna svojstva netopljivih kompleksa i urušenoga gela pokazuju daje lamelno uređenje stuktuma značajka kompleksa karagena i kationske površinski akivne tvari.Nanocomplexes formed from anionic biopolymers, carrageenans, and cationic surfactant have been investigated for their applicability in drug delivery. Stucture and complex size from nano- to microdimension strongly depends on concentration and concentration ratio of both components and linear charge density on carrageenan chains. Factors governing the complex formation are electrostatic and hydrophobic interactions as well as conformation of the carrageenan chains. With increasing carrageenan concentration, the intra-macromolecular complexes change to inter-macromolecular, which subsequently reorganize into bettei ordered structures, giant vesicles, precipitate - dodecylammonium carrageenate and gels. Formation of giant vesicles and structural properties of insoluble complexes and collapsed gels revealed lamellar ordering as an important feature of the carrageenan and an oppositely charged surfactant complexes

SPECIFIC FEATURES OF SME FINANCING IN CROATIA COMPARED TO THE EUROPEAN COUNTRIES

U ovome radu prikazani su načini klasifikacije SME sektora u Hrvatskoj u odnosu na zemlje Europske unije. Cilj istraživanja bio je utvrditi klasifikaciju SME sektora u Hrvatskoj u odnosu na zemlje EU-a. Kvalitativnim znanstvenim metodama indukcije i dedukcije utvrđeno je da se udio SME sektora u Hrvatskoj ne razlikuje od zemalja Europske unije. Tipični kriteriji klasifikacije kod većine zemalja su broj zaposlenih, veličina prihoda i aktive. Pregledom literature, a osobito istraživanja koja su provela državna tijela zadužena za SME sektor, utvrđeni su udjeli SME sektora u ukupnom gospodarstvu Hrvatske te je potom izvršena usporedba sa zemljama Europske unije. I u ovome dijelu istraživanja vidljivo je da se Hrvatska uklapa u europski prosjek. Na razini Europske unije udio SME sektora veći je od 90 %, a Hrvatska se s gotovo 98 % uklapa u navedeni prosjek. U radu se dolazi do specifičnog cilja, a to je utvrđivanje tipičnih izvora financiranja SME sektora. Temeljem cilja istraživanja postavljena je i hipoteza da se tipični izvori financiranja SME sektora u Hrvatskoj ne razlikuju od Europske unije. Hipoteza je dokazana metodama indukcije i dedukcije sekundardnih podataka. U posljednjem dijelu rada navode se rezultati istraživanja i specifični načini financiranja. Uz tipične oblike financiranja kao što su bankarski krediti i ostali zajmovi navode se i financijske potpore koje su odobrili fondovi Europske unije.This paper analyzes the classification of the SME sector in Croatia compared to other EU countries. The main goal of this research was to define the SME classification in Croatia compared to other EU countries. The usual classification criteria are the number of employees, annual revenue and assets. On the basis of criteria analysis, similarities and differences in defining SMEs have been determined. Based on literature review, mainly research analyses conducted by public authorities in specific countries in charge of the SME sector, the SME share in the whole Croatian economy has been determined. The EU share of SME is more than 90%, and Croatia with the share of almost 98% definitely follows the trend. According to the main goal of this paper, the hypothesis has been put forward stating that typical financing types of the SME sector in Croatia do not significantly differ from the EU’s ones. The hypothesis has been confirmed with scientific descriptive methods of induction and deduction on the basis of secondary data. The last part of the paper deals with the research result and outlines specific financing types. Along with typical financing types such as bank loans and other types of loans, some special financial aid programs financed by the EU have also been mentioned

Integral Wheat Flour Based Biscuits as Sources of Phosphorus in Everyday Nutrition

Eight experimental integral wheat fl our based biscuits were prepared and investigated for total and bioavailable phosphorus content. Results were compared to the values obtained for classic white wheat fl our based biscuits in order to asses the impact of implantation of bran, different integral raw materials and fibers on the total phosphorus content and its availability. Since a study was conducted in the view of current trends of the excessive intake of this element in most of the developed countries, we expressed results obtained for total phosphorus content as percentages of allocated RDA values. Total phosphorus was determined by an offi cial AOAC method (AOAC 2001) and its bioavailability by an in vitro enzymatic method (Schwedt et al. 1998). Total phosphorus content of investigated samples ranged from 1.093 g kg-1 (biscuit based on type 500 wheat fl our) to 2.987 g kg-1 (biscuit enriched with integral wheat fl our and amaranth). Phosphorus availability was the highest in biscuit based on type 500 wheat fl our, as expected (86.1 %), and the lowest in the sample enriched with amaranth fl our (53.0 %), due to a very high phytic acid content. Considering revealed values of total phosphorus content and its bioavailability, we concluded that the richest source of this important macroelement was the sample enriched with soy flour providing 1.671 g kg-1 of available phosphorus

Nitrogen and Phosphorus Content, Hectoliter Weight and Yield Variations of Wheat Grain as Aff ected by Cropping Intensity

Public concerns over the potential environmental hazards of intensive agriculture have renewed an interest in the low-input nitrogen (N) fertilization practices for wheat (Triticum aestivum L.). A two-year study (2001 and 2002) was conducted to determine the infl uence of cropping intensity, namely the low-N (67 kg N ha-1) and high-N (194 kg N ha-1) input levels on the grain N and phosphorus (P) content, phytate-P (phytic acid and its salts), hectoliter weight and grain yield of three bread wheat cultivars widely grown in Croatia. Growing conditions significantly affected grain yields averaging 6641 kg ha-1 in the fi rst growing season and 8295 kg ha-1 in the following year. Despite an associated increase in the 1000-grain weights, the use of the low-N fertilization brought about a significant decrease in grain yield, hectoliter weight and grain N content in all cultivars by an average of 18.1%, 1.5% and 22.6%, respectively, when compared to the high-N fertilization level. The reductions in grain N content were consistent in both years regardless of variations in grain yields among three tested cultivars. Grain N content under the low-N fertilization averaged 17.1 g kg-1 only, which may limit its use for breadmaking. In contrast, grain P content was not affected by N fertilization or growing season and averaged 4.70 g kg-1 across all treatments. Absolutely small, but significant differences existed among cultivars for total grain P content, of which about 80% was in the form of phytate-P. A negative correlation between the 1000-grain weight and P content was found because of tendency toward lower P content in heavier grains. When compared to the high-N input, the low-N fertilization practices for wheat crop were associated with a significant decrease in grain yield and grain N content in all cultivars, but had no effect on grain P content regardless of cultivar

Release of Trichoderma viride Spores from Microcapsules Simultaneously Loaded with Chemical and Biological Agents

Recent studies of bioactive agents, simultaneous encapsulation in chitosan/alginate microcapsules revealed that encapsulation in the same compartment does not inhibit activity either of Trichoderma viride spores nor copper cations. The objective of this work was to investigate the influence of formulation variables (concentration of copper cations, chitosan layer and microcapsule size) on T. viride spores release. Results showed that the increase in copper cation concentration promoted, but the increase in microcapsule size and presence of the chitosan layer on microcapsule surface reduced T. viride spores release. Fitting to simple Korsmeyer–Peppas empirical model elucidated the underlying mechanism of release. Fickian diffusion controlled release from microcapsules without chitosan layer and smaller microcapsules with chitosan layer, whereas anomalous diffusion mechanism (a combination of the diffusion and erosion mechanisms) was found to be the rate-controlling mechanism from larger microcapsules with chitosan layer. The investigation showed that proper selection of formulation variables helps in designing microcapsules with the desirable release of T. viride for plant protection and nutrition

Incidence algebras

U ovom radu proučavali smo incidencijske algebre. Na početku smo definirali parcijalno uređen skup, lokalnu konačnost parcijalno uređenog skupa te naveli nekoliko primjera. Nakon toga uveden je pojam incidencijske algebre lokalno konačnog parcijalno uređenog skupa nad komutativnim prstenom Rs jedinicom. Pokazano je da je incidencijska algebra po strukturi asocijativna R-algebra s jedinicom te da se može uložiti u algebru trokutastih matrica.Središnji dio rada bavi se računanjem Moebiusove funkcije na elementima parcijalno uređenog skupa te generaliziranim formulama Moebiusove inverzije.Primjena Moebiusove inverzije ilustrirana je na primjerima iz kombinatorike.Nadalje, definirali smo pojam E-funkcije incidencijske algebre, gdje je E relacija ekvivalencije te je pokazana veza između incidencijske algebre i skupa svih E-funkcija u njoj. Uveden je pojam reducirane incidencijske algebre te je dana karakterizacija reducirane incidencijske podalgebre konačnog parcijalno uređenog skupa nad poljem. Konačno, dani su primjeri koji nam pokazuju vezu reduciranih incidencijskih podalgebri s prstenima formalnih redova potencija.In this thesis we study incidence algebras. At the beginning, we define a partially ordered set, local finiteness of a partially ordered set and give several examples. After that we introduce the concept of incidence algebra of a locally finite partially ordered set over a commutative ring R with identity. It is shown that the incidence algebra is an associative R-algebra with identity and that it can be embedded into the algebra of triangular matrices. The central part of the thesis deals with the calculation of the Moebius function on the elements of a partially ordered set and with the generalized formulas of Moebius inversion. Applications of Moebius inversion are illustrated by examples from combinatorics. In addition, we define the concept of E-functions in an incidence algebra, where E is an equivalence relation, and we show the connection between the incidence algebra and the set of all E-functions in it.The concept of reduced incidence algebra is introduced and a characterization of the reduced incidence subalgebra of a finite partially ordered set over a field is given. Finally, we give examples that show connections between reduced incidence subalgebras and rings of formal power series

Incidence algebras

U ovom radu proučavali smo incidencijske algebre. Na početku smo definirali parcijalno uređen skup, lokalnu konačnost parcijalno uređenog skupa te naveli nekoliko primjera. Nakon toga uveden je pojam incidencijske algebre lokalno konačnog parcijalno uređenog skupa nad komutativnim prstenom Rs jedinicom. Pokazano je da je incidencijska algebra po strukturi asocijativna R-algebra s jedinicom te da se može uložiti u algebru trokutastih matrica.Središnji dio rada bavi se računanjem Moebiusove funkcije na elementima parcijalno uređenog skupa te generaliziranim formulama Moebiusove inverzije.Primjena Moebiusove inverzije ilustrirana je na primjerima iz kombinatorike.Nadalje, definirali smo pojam E-funkcije incidencijske algebre, gdje je E relacija ekvivalencije te je pokazana veza između incidencijske algebre i skupa svih E-funkcija u njoj. Uveden je pojam reducirane incidencijske algebre te je dana karakterizacija reducirane incidencijske podalgebre konačnog parcijalno uređenog skupa nad poljem. Konačno, dani su primjeri koji nam pokazuju vezu reduciranih incidencijskih podalgebri s prstenima formalnih redova potencija.In this thesis we study incidence algebras. At the beginning, we define a partially ordered set, local finiteness of a partially ordered set and give several examples. After that we introduce the concept of incidence algebra of a locally finite partially ordered set over a commutative ring R with identity. It is shown that the incidence algebra is an associative R-algebra with identity and that it can be embedded into the algebra of triangular matrices. The central part of the thesis deals with the calculation of the Moebius function on the elements of a partially ordered set and with the generalized formulas of Moebius inversion. Applications of Moebius inversion are illustrated by examples from combinatorics. In addition, we define the concept of E-functions in an incidence algebra, where E is an equivalence relation, and we show the connection between the incidence algebra and the set of all E-functions in it.The concept of reduced incidence algebra is introduced and a characterization of the reduced incidence subalgebra of a finite partially ordered set over a field is given. Finally, we give examples that show connections between reduced incidence subalgebras and rings of formal power series

Incidence algebras

U ovom radu proučavali smo incidencijske algebre. Na početku smo definirali parcijalno uređen skup, lokalnu konačnost parcijalno uređenog skupa te naveli nekoliko primjera. Nakon toga uveden je pojam incidencijske algebre lokalno konačnog parcijalno uređenog skupa nad komutativnim prstenom Rs jedinicom. Pokazano je da je incidencijska algebra po strukturi asocijativna R-algebra s jedinicom te da se može uložiti u algebru trokutastih matrica.Središnji dio rada bavi se računanjem Moebiusove funkcije na elementima parcijalno uređenog skupa te generaliziranim formulama Moebiusove inverzije.Primjena Moebiusove inverzije ilustrirana je na primjerima iz kombinatorike.Nadalje, definirali smo pojam E-funkcije incidencijske algebre, gdje je E relacija ekvivalencije te je pokazana veza između incidencijske algebre i skupa svih E-funkcija u njoj. Uveden je pojam reducirane incidencijske algebre te je dana karakterizacija reducirane incidencijske podalgebre konačnog parcijalno uređenog skupa nad poljem. Konačno, dani su primjeri koji nam pokazuju vezu reduciranih incidencijskih podalgebri s prstenima formalnih redova potencija.In this thesis we study incidence algebras. At the beginning, we define a partially ordered set, local finiteness of a partially ordered set and give several examples. After that we introduce the concept of incidence algebra of a locally finite partially ordered set over a commutative ring R with identity. It is shown that the incidence algebra is an associative R-algebra with identity and that it can be embedded into the algebra of triangular matrices. The central part of the thesis deals with the calculation of the Moebius function on the elements of a partially ordered set and with the generalized formulas of Moebius inversion. Applications of Moebius inversion are illustrated by examples from combinatorics. In addition, we define the concept of E-functions in an incidence algebra, where E is an equivalence relation, and we show the connection between the incidence algebra and the set of all E-functions in it.The concept of reduced incidence algebra is introduced and a characterization of the reduced incidence subalgebra of a finite partially ordered set over a field is given. Finally, we give examples that show connections between reduced incidence subalgebras and rings of formal power series