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Zeolites are used in many fields of human activities [1]. Besides, new potential applications constantly emerge so understanding their possible impact on the environment is necessary [2]. In the frame of this study, zeolite beta nanoparticles were synthesized and characterized by a complimentary set of experimental techniques. Their potential negative impact towards environment was evaluated using zebrafish Danio rerio embryos embryotoxicity test [3]. Such a comprehensive study pinpointed zeolite nanoparticles as safe materials and opened the door for their application, but also emphasized the need to reduce the presence of organic structure directing agents in nanosized zeolite synthesis reaction mixtures.

Nanoselenium regulated growth and lipid production of Dunaliella tertiolecta- increasing microalgal potential for biofuel production was investigated.

The present study was undertaken to evaluate the environmental impact of olive mill wastewater (OMW) to living organisms, to identify the OMW components among phenolic group which are directly correlated with OMW’s toxicity and to complete this research with pointing out a huge potential of their use as a renewable resource.

Selenium (Se) is a natural trace element which has large positive and negative environmental impacts that may alternate from an essential micronutrient to a toxic compound within a narrow concentration level. Investigation of selenium nanoparticles (SeNPs) as a possible source of selenium has just recently begun. They have received a lot of attention due to their lower toxicity when compared to sodium selenite (Na2SeO3). Although higher doses of SeNPs may have a negative impact on different processes in algae, lower doses can increase algal biomass without any toxic cellular effect. The objective of this study was to investigate the effects of different SeNPs concentrations on marine microalgae Dunaliella tertiolecta. Algae were cultured under a wide range of different SeNPs concentrations up to 14 days, followed by determination of chlorophyll a, total lipid and protein content, as well as composition of fatty and amino acids. The results have shown that lower concentrations caused a significant increase of biomass concentration and chlorophyll a content, contrary to results obtained in samples with higher SeNPs concentrations. Total protein content and productivity were similar at all tested SeNPs concentrations. Fatty acids, determined by using gas chromatography (GC), had higher content of unsaturated fatty acids in all tested samples. These results provide a better understanding of the effect of SeNPs on green microalgae, which may help in the development of new biotechnological applications considering that nanotechnology becomes a promising tool in many fields of research.

The objective of this study was to evaluate the potential application of sodium selenite as neutral lipid inductor in marine microalgae Dunaliella tertiolecta which could favor the production of potential microalgae derived- biodiesel.

Mikroalge su prokariotski ili eukariotski fotosintetski mikroorganizmi jednostavne stanične građe koji predstavljaju bogat izvor karotenoida, vitamina i fenola. Dobre karakteristike mikroalgi, poput brzog rasta uz korištenje ugljičnog dioksida, visokih prinosa biomase, sposobnosti skladištenja esencijalnih hranjivih tvari i mogućnosti primjene genetskih modifikacija, osnova su njihove široke primjene u različitim granama industrije. Mikroalge mogu sintetizirati antioksidativne molekule (npr. polifenoli) koje sprječavaju peroksidaciju lipida i time produljuju rok trajanja prehrambenih proizvoda. Nedovoljno literaturnih podataka o antioksidativnoj aktivnosti polifenola iz ekstrakata mikroalgi predstavlja prepreku njihove uporabe u prehrambenoj industriji. Glavni cilj ovog istraživanja bio je utvrditi antioksidativnu aktivnost ekstrakata morske mikroalge Dunaliella tertiolecta ovisno o načinu sušenja, predtretmanu i vrsti ekstrakcije. Za svaki od ekstrakata određen je ukupan udio polifenola i njihova antioksidativna aktivnost. Prema rezultatima, udio polifenola i kapacitet antioksidativne aktivnosti zabilježen na uzorcima liofilizirane biomase mikroalge D. tertiolecta veći je u odnosu na uzorke komercijalno dostupnih slatkovodnih mikroalgi (Chlorella vulgaris). Dobiveni rezultati dali su uvid u optimalne uvjete ekstrakcije mikroalge D. tertiolecta i ukazali na njezin potencijal primjene u prehrambenoj industriji. Istraživanja su pomogla u razumijevanju postupaka ekstrakcije i iskoristivosti dobivenih ekstrakata mikroalgi u stvaranju ekonomski održivog i isplativog proizvodnog postupka sinteze prirodnih antioksidansa.

Corn cob hydrolysate was used as carbon source for microbial lipids production by the oleaginous fungus Mortierella isabellina. In order to improve the enzymatic digestibility, corn cobs were subjected to alkaline pretreatment with NaOH and acid pretreatment with H2SO4. Pretreatment process was carried out at different NaOH and H2SO4 concentrations, temperature and residence time. Optimal pretreatment conditions were chosen based on glucose and xylose yield by enzymatic hydrolysis of pretreated biomass. The highest efficiency of enzymatic hydrolysis was obtained with corn cobs pretreated with 2 % w/w NaOH at 121oC and residence time of 1 hour, 2 % w/w NaOH at 50oC and residence time of 6 hours and 1 % w/w H2SO4 at 121oC and residence time of 20 min. Furthermore, the effect of enzyme and substrate loading rate on efficiency of enzymatic hydrolysis of pretreated corn cobs was also studied. The highest efficiency of glucan and xylan hydrolysis was achieved at 20 % (g/g) substrate loading rate and 30 FPU g-1 of enzyme loading rate. Oleaginous fungus Mortierella isabellina was cultivated on the enzymatic hydrolysate of corn cobs pretreated with 2 % w/w NaOH at 50 oC for 6 hours. The microbial lipid content in fungal biomass reached up to 45 % of biomass dry weight, while lipid productivity and lipid concentrations were 0, 051 gL-1h-1 and 24, 21 gL- 1, respectively.

Antioxidants are valuable molecules capable to inhibit possibly harmful oxidation, a chemical reaction whereby produced free radicals can damage cells and cause different diseases. To prevent cellular damage, marine and freshwater microalgae have developed antioxidant defence mechanisms and have attracted considerable attention as a promising source of natural antioxidants to replace synthetic antioxidants for food and chemical industry applications. The main goal of this study was to determine the difference in potential antioxidant capacities of marine algae Dunaliella tertiolecta and freshwater algae Chlorella vulgaris using fast electrochemical method named voltammetry of immobilized microparticles. This method allows determination of electroactive compounds in crystalline state without prior preparation of the sample. Aliquots of powdered dried algae were placed on a ceramic tile forming a spot of finely distributed material. Afterwards they were abrasively transferred to the surface of paraffin impregnated graphite electrode by rubbing the electrode rod with its lower circular surface on that spot of the sample. Measurements were preformed using cyclic and square-wave voltammetry in 0.1 M KNO3 on both tested samples with changing the experimental conditions (scan rate and frequency) for both techniques. In addition, changing the pH- value of electrolyte gave insight into to electrochemical mechanism of tested samples. For tested algae, different results were obtained which corresponds to their different antioxidant capacity

Lignocellulose is a potential raw material for sustainable production of biofuels and biochemicals, but to use lignocellulose in bioprocesses it is necessary to convert cellulose and hemicellulose to fermentable sugars. In this work the results of wheat straw pre-treatment with 2% H3PO4, in high-pressure reactor at different temperatures (160°C - 200°C) and retention times (1 min – 10 min), are shown. During dilute acid pre-treatment hemicellulose is degraded to pentose sugars that cannot be used by industrial ethanol producing yeasts. Therefore, to improve overall bioprocess efficiency a genetically engineered Saccharomyces cerevisiae strain, that can utilize xylose, was used. Fermentations were performed on different hydrolysates in shake-flasks, and in horizontal rotating tubular bioreactor. Efficiencies for fermentations carried out in shake flasks were in the range from 19.6% to 74.5%. The maximum efficiency of 88.2% was achieved during fermentation in HRTB. The acquired results were also used for life cycle analysis of the ethanol production process. For the quantification of process sustainability, specific partial area atot was calculated using SPIonExcel program. Value of atot represents environmental impact, and economic and ecological sustainability. The partial specific area for this ethanol production process is 7782.06 m2 for 1 kg of ethanol produced, that is 2-3 times lower compared to, a simultaneous saccharification and fermentation process (SSF) described in Morikawa [1] atot=21401.5 m2, and a separate enzymatic hydrolysis and fermentation process (SHF) presented in Saha [2] atot=16701.9 m2.

Selenium (Se), essential natural trace element for various organisms recently attracts attention due to its potential beneficial effects in various fields, i.e. biomedicine, electronics and some other industrial applications. However, depending on the dose, it can exhibit adverse effects. Current opinion is that possible Se toxicity could be reduced if Se is applied in the form of nanoparticles. Despite this, little is known about possible negative impact of SeNPs on different organisms. In general, when addressing nanotoxicity, aquatic organisms are of major interest, since majority of engineered nanoparticles are released through waters into environment. In aquatic ecosystem microalgae acts as a major vector of Se transport from water to filter-feeders and other consumers. With the aim to determine safety of their use in cosmetic, food and pharmaceutical industry the influence of SeNPs on growth of freshwater microalgae Chlorella vulgaris and marine microalgae Dunaliella tertiolecta was compared to the influence of sodium selenite (NaSe2O3), inorganic Se source. SeNPs were synthesized by solution phase synthesis and characterized using powder X-ray diffraction. The hydrodynamic diameter and zeta potential of SeNPs were determined by dynamic and electrophoretic light scattering. Obtained results may contribute to the understanding of SeNPs toxicity and their biotechnological potential.

Selenium (Se) is a micronutrient metabolically required by a variety of organisms, including microalgae and bacteria. Chlorophyta (green algae) is a large group of aquatic photosynthetic organisms and about half of the global microalgal production corresponds to green microalgae (Chlorella and Dunaliella) species. The range of Se concentrations within Se uptake goes from insufficient to toxic is very narrow. Se toxicity depends on its chemical structure and concentration and it is species- and dose- dependent in the case of microalgae. Recently, instead of sodium selenite (inorganic Se form), selenium nanoparticles (SeNPs) have obtained the attention as a possible Se source because of its lower toxicity. With the aim to determine safety of their use in cosmetic, food and pharmaceutical industry, the influence of SeNPs on growth and chlorophyll a content of freshwater microalgae Chlorella vulgaris and marine microalgae Dunaliella tertiolecta was compared with the influence of sodium selenite. Within this study, SeNPs were synthesized by solution phase synthesis and characterized using powder X-ray diffraction to examine SeNPs composition and phase. The hydrodynamic diameter and zeta potential of SeNPs were determined by dynamic and electrophoretic light scattering. These results provide a better understanding of the effect of SeNPs on green microalgae and their biotechnological potential, which may help in the development of new technological applications considering that nanotechnology becomes a promising tool in many fields of research such as pharmacy, environmental, information technology and engineering, chemical industries, and others.

The lecture comprised novel findings on biofuel, being non-polluting, locally available, accessible, sustainable and reliable fuel obtained from renewable sources. Biodiesel and bioethanol are known excellent alternative fuels. Their production may origin from resources of biomass – food crops, crop wastes, fruits, woody parts of plants, garbage, and particularly algae.

The effect of dilute H2SO4 and NaOH in corn cob pretreatment was studied. As measure for pretreatment efficiency, enzymatic digestibility of the pretreated biomass was determined. The influence of acid and alkali concentration, temperature and time of pretreatment was studied. After enzymatic hydrolysis of pretreated biomass, the best conditions for alkali and acid pretreatment were selected. The effect of enzyme and substrate loading rate on efficiency of enzymatic hydrolysis of pretreated corn cobs was studied for selected pretreatment conditions. The highest efficiency was achieved at 20% substrate loading and 30 FPU g-1 glucan of enzyme loading. With corn cobs pretreated at 2 % NaOH at 50oC and residence time of 6 hour hydrolysis efficiency of glucan and xylan was 85, 71 % and 73, 53 %, respectively. Enzymatic hydrolysate of corn cobs pretreated on these conditions was used for cultivation of oleaginous fungus Mortierella isabellina, and microbial lipid concentration of 24, 21 g L-1 was achieved. Based on fatty acid composition it is proved that biodiesel produced from microbial lipids from Mortierella isabelina fulfill European biodiesel standard.

Bioetanol je važan obnovljiv izvor energije koji ima veliki potencijal za zamjenu fosilnih transportnih goriva. Velike količine jeftinih industrijskih i poljoprivrednih ostataka idealne su sirovine za proizvodnju bietanola pri čemu se njihovim zbrinjavanjem sprječava zagađenje okoliša. Pšenična slama je dobar primjer takve sirovine koji se može primjeniti u procesu proizvodnje bioetanola. Međutim, pšenična slama mora proći proces predobrade da bi se mogla primjeniti u procesu proizvodnje bioetanola. U ovom istraživanju proučavan je proces blago kisele hidrolize pomoću fosforne kiseline u visokotlačnom reaktoru pri različitim kombinacijama parametara procesa predobrade. Proučavane su različite kombinacije svih parametara procesa predobrade: temperatura (160 – 200 °C), vrijeme zadržavanja (1 - 10 minuta) i koncentracije fosforne kiseline (0,5 – 2,0 %). Najveća koncentracija fermentabilnih šećera zabilježena je u tekućem dijelu hidrolizata pšenične slame kod predobrade na 180 °C, vremenu zadržavanja od 10 minuta i koncentraciji H3PO4 od 2,0 %. U čvrstom dijelu hidrolizata pšenične slame kod prethodno navedenih uvjeta detektirani su ovi sastojci: glukan (42,43 %), ksilan (19,64 %), arabinan (9,01 %). Dobiveni hidrolizati pšenične slame korišteni su za anaerobni uzgoj divljeg i genetički modificiranog soja (Y9) kvasca S. cerevisiae u Erlenmeyer tikvicama i horizontalno rotirajućem cijevnom bioreaktoru. Najuspješniji anaerobni uzgoj genetički modificiranog soja kvasca S. cerevisiae Y9 proveden je na hidrolizatu pšenične slame dobivenom pri temperaturi od 180 °C, vremenu zadržavanja od 10 minuta i koncentraciji fosforne kiseline od 2,0 % u HRCB-u pri čemu su dobiveni ovi pokazatelji uspješnosti bioprocesa: Pr: 0,0057 gL-1h-1, YP/S: 0,058 gg-1, E: 11,34 %. Bioethanol is an important renewable energy source that has great potential to replace fossil transportation fuels. Large quantities of cheap industrial and agricultural residues are the ideal raw materials for the production of bioethanol, whereby their disposal prevents environmental pollution. Wheat straw is a good example of such raw materials that can be applied in the production process of bioethanol. However, wheat straw has to go through the process of pretreatment that could be applied in the production process of bioethanol. In this study, the process of mild acid hydrolysis by phosphoric acid in a high - pressure reactor at various combinations of processing parameters was studied. Various combinations of all processing parameters: temperature (160 - 200 °C), holding time (1 - 10 minutes) and phosphoric acid concentration (0.5 - 2.0%) were studied. The highest concentration of fermentable sugar was observed in the liquid hydrolyzate of wheat straw pretreated at 180 °C, residence time of 10 minutes and a concentration of 2,0 % H3PO4. In the solid hydrolyzate of wheat straw, at previous conditions, these components are detected: glucan (42,43 %), xylan (19,64 %), arabinan (9,01 %). The obtained hydrolyzate of wheat straw was used for anaerobic cultivation of wild and genetically modified yeast S. cerevisiae, Y9 in Erlenmeyer flasks and horizontally rotating tubular bioreactor. The most successful anaerobic cultivation of genetically modified yeast S. cerevisiae, Y9 was carried out on the hydrolyzate of wheat straw obtained at 180 °C, 10 minute retention time and 2.0% phosphoric acid concentration in HRCB, where these bioprocess performance indicators were obtained: Pr: 0.0057 gL-1h-1, YP / S: 0.058 gg-1, E: 11.34%.

Увод: Процена минималних неуролошких дисфункција (МНД) пружа информације о неуролошком стању детета, помаже у идентификовању вулнерабилности детета ка развоју моторних слабости, тешкоћа у учењу или поремећаја понашања. Деформитети кичменог стуба код деце предшколског узраста су у сталном порасту. Циљ истраживања: Утврђивање преваленце МНД-а у узорку предшколске деце тестирањем по Touwen-у, евалуација постуралног статуса код деце предшколског узраста, као и утврђивање повезаности јављања минималних неуролошких дисфункција и постуралних поремећаја код деце предшколског узраста. Материјал и методе: Истраживање је урађено у предшколској установи „Радосно детињство“ из Новог Сада. Укупан узорак је обухватио 120-оро деце која су подељена у две групе у односу на узраст, 60-оро деце старости од 6 до 7 година (група А) и 60-оро деце старости од 5 до 6 година (група Б). Методом случајног избора су изабрана три вртића из различитих делова града, а деца су насумично одабрана са приближно једнаком заступљеношћу пола. Тестирање је урађено са Touwen-овим тестом модификованим од стране Hadders-Algre. Резултати су груписани у три групе: одсуство, присуство једноставних (присуство једне или две области дисфункције) и присуство комплексних МНД (присуство најмање три области дисфункције). Код све деце урађена је евалуација постуралног статуса, као и антропометријска мерења. Резултати: Постоји статистички значајна разлика у учесталости јављања МНД-а у односу на узраст, одступања су чешће присутна у млађем узрасту. МНД се чешће јављају код дечака у односу на девојчице, али није показана статистички значајна разлика. Код 68,3% деце уочени су елементи лошег држања тела. Најчешћа одступања од нормалног постуралног положаја била су у виду спуштених стопала (45,8%), асиметрије висине рамена (35%), искривљења ахилових тетива ван (30%), повећања слабинске кривине (29,2%) и асиметрије троуглова стаса (20%). Утврђена је статистички значајна позитивна повезаност између јављања минималних неуролошких дисфункција и лошег држања тела код деце предшколског узраста. Закључак: Деца старијих (узраст од 5 до 6 година) група предшколског узраста знатно чешће испољавају знаке минималне неуролошке дисфункције у односу на децу најстаријих (узраст од 6 до 7 година) група. Више од половине деце предшколског узраста показује одступање од нормалног постуралног статуса. Постоји статистички значајна позитивна повезаност између јављања минималних неуролошких дисфункција и лошег држања тела код деце предшколског узраста., Uvod: Procena minimalnih neuroloških disfunkcija (MND) pruža informacije o neurološkom stanju deteta, pomaže u identifikovanju vulnerabilnosti deteta ka razvoju motornih slabosti, teškoća u učenju ili poremećaja ponašanja. Deformiteti kičmenog stuba kod dece predškolskog uzrasta su u stalnom porastu. Cilj istraživanja: Utvrđivanje prevalence MND-a u uzorku predškolske dece testiranjem po Touwen-u, evaluacija posturalnog statusa kod dece predškolskog uzrasta, kao i utvrđivanje povezanosti javljanja minimalnih neuroloških disfunkcija i posturalnih poremećaja kod dece predškolskog uzrasta. Materijal i metode: Istraživanje je urađeno u predškolskoj ustanovi „Radosno detinjstvo“ iz Novog Sada. Ukupan uzorak je obuhvatio 120-oro dece koja su podeljena u dve grupe u odnosu na uzrast, 60-oro dece starosti od 6 do 7 godina (grupa A) i 60-oro dece starosti od 5 do 6 godina (grupa B). Metodom slučajnog izbora su izabrana tri vrtića iz različitih delova grada, a deca su nasumično odabrana sa približno jednakom zastupljenošću pola. Testiranje je urađeno sa Touwen-ovim testom modifikovanim od strane Hadders-Algre. Rezultati su grupisani u tri grupe: odsustvo, prisustvo jednostavnih (prisustvo jedne ili dve oblasti disfunkcije) i prisustvo kompleksnih MND (prisustvo najmanje tri oblasti disfunkcije). Kod sve dece urađena je evaluacija posturalnog statusa, kao i antropometrijska merenja. Rezultati: Postoji statistički značajna razlika u učestalosti javljanja MND-a u odnosu na uzrast, odstupanja su češće prisutna u mlađem uzrastu. MND se češće javljaju kod dečaka u odnosu na devojčice, ali nije pokazana statistički značajna razlika. Kod 68,3% dece uočeni su elementi lošeg držanja tela. Najčešća odstupanja od normalnog posturalnog položaja bila su u vidu spuštenih stopala (45,8%), asimetrije visine ramena (35%), iskrivljenja ahilovih tetiva van (30%), povećanja slabinske krivine (29,2%) i asimetrije trouglova stasa (20%). Utvrđena je statistički značajna pozitivna povezanost između javljanja minimalnih neuroloških disfunkcija i lošeg držanja tela kod dece predškolskog uzrasta. Zaključak: Deca starijih (uzrast od 5 do 6 godina) grupa predškolskog uzrasta znatno češće ispoljavaju znake minimalne neurološke disfunkcije u odnosu na decu najstarijih (uzrast od 6 do 7 godina) grupa. Više od polovine dece predškolskog uzrasta pokazuje odstupanje od normalnog posturalnog statusa. Postoji statistički značajna pozitivna povezanost između javljanja minimalnih neuroloških disfunkcija i lošeg držanja tela kod dece predškolskog uzrasta., Introduction: Assessment of minor neurological dysfunction (MND) provides information about a child's neurological condition, which helps to identify the vulnerability of the child to the development of motor impairment, difficulties in learning or behavioral disorders. Spinal deformities in preschool children are constantly increasing. Aim: Determining the prevalence of MND in a sample of preschool children using Touwen’s test, the evaluation of postural status in preschool children, as well as determining the relation between the occurrence of minor neurological dysfunction and postural disorders in preschool children. Material and methods: The examination was carried out in the preschool institution “Radosno detinjstvo” in the city of Novi Sad. The total sample included 120 children who were divided into two groups according to their age, 60 children aged 6 to 7 years (group A) and 60 children aged 5 to 6 years (group B). The children were recruited at three randomly selected kindergartens, and the children were randomly selected with approximately equal gender representation. The testing was done with Touwen's test modified by Hadders-Algra. The results were classified into three groups: the absence of MND, the presence of simple MND (presence of one or two domains of dysfunction) and the presence of complex MND (presence of at least three domains of dysfunction). Evaluation of postural status and anthropometric measurements were carried out for all the children. Results: There is a statistically significant difference in the prevalence of MND in relation to age, variations were more likely at a younger age. MND is more frequent in boys than in girls, but this difference is not statistically significant. In 68.3% of the children there are elements of bad posture. The most common deviations from the normal postural position are flat feet (45.8%), shoulder height asymmetry (35%), distortion of Achilles tendons to the outside (30%), excessive curvature of lower back (29.2%) and asymmetry of stature triangles (20%). There is a statistically significant positive correlation between the occurrence of minor neurological dysfunction and poor posture in children of preschool age. Conclusion: Children in older preschool groups (5 to 6 years old) more often show signs of minor neurological dysfunction in comparison to the children in the oldest groups (6 to 7 years old). More than half of the preschool children show deviation from normal postural status. There is a statistically significant correlation between the occurrence of minor neurological dysfunction and poor posture in children of preschool age.

Wheat straw hydrolysates (obtained by diluted sulphuric acid pre-treatment) were used as substrates for anaerobic cultivation of genetically modified strain of Saccharomyces cerevisiae. Wheat straw pre-treatment process was carried out in the high-pressure reactor under different temperatures (150 - 200 °C) and retention times (1 - 10 min) with 0, 5 % w/w sulphuric acid. The highest mass fraction of xylans (68, 64 % w/w) in the wheat straw hydrolysate was observed at 160 °C and residence time of 5 minutes and the highest mass fraction of glucans (30, 42 % w/w) at 200 °C and residence time of 10 minutes, respectively. Genetically modified strain of Saccharomyces cerevisiae has ability to use hexoses and pentoses as a carbon source. The initial kinetic study (e.g. growth rate and ethanol synthesis) of modified yeast strain was carried out in small scale. The most successful ethanol production was observed on the wheat straw hydrolysates obtained at 180 °C and residence time of 10 minutes. In these conditions, bioethanol production efficiency was 43, 25 % and bioprocess productivity of 0, 045 g L-1 h-1, respectively. During anaerobic cultivation of genetically modified S. cerevisiae in the horizontal rotating tubular bioreactor on the same hydrolysate, bioprocess productivity was 0, 143 g L-1 and efficiency of 64, 01 %, respectively.

U ovom diplomskom radu je opisana tehnologija digitalnog mobilnog radija koja se rabi za izgradnju privatnih mobilnih mreža. Detaljnije je obrađen fizički sloj i neke specifičnosti navedene tehnologije. Pomoću programskog jezika Pathloss napravljeno je radijsko planiranje geografskog područja Republike Hrvatske uz optimalan broj odašiljačkih postaja. Provedena su mjerenja prijamnog signala za kritične točke na području pokrivanja repetitora Sljeme i analizirana je točnost rezultata dobivenih simulacijom. Dan je osvrt DMR tehnologije u usporedbi s TETRA tehnologijom koja je najzastupljenija tehnologija koja se rabi za realizaciju privatnih mreža. This thesis describes the technology of digital mobile radio that is used for the construction of private mobile network. Detailed physical layer is processed and some specifics of this technology. Using the programming language Pathloss, radio planning of Croatian territory is made with optimum number of transmitting stations. Measurements of receiving signals are made at critical points in the area covered by the repeater Sljeme and accuracy of the results obtained by simulation was analyzed. An overview is given of DMR technology compared with TETRA technology which is the most common technology used to implement private networks.

Cilj ovog istraživanja bio je provjeriti ulogu spola, stila privrženosti i statusa veze u objašnjenju emocionalne i seksualne ljubomore u bliskim vezama. Status veze operacionaliziran je kao duljina trajanja veze i razina obvezivanja unutar iste. U istraživanju je sudjelovalo 223 sudionika u dobi od 20 do 35 godina. Svi su sudionici u trenutku ispunjavanja upitnika bili u nekom obliku romantičnog odnosa, a upute i čestice na korištenim instrumentima modificirane su tako da se odnose na trenutni odnos sudionika. U istraživanju su korišteni opći upitnik o osnovnim demografskim podacima sudionika, skraćena verzija Inventara iskustava u bliskim vezama, mjera ljubomore određena metodom prisilnog izbora, te skale ljubomore Likertovog tipa. U ovom su istraživanju žene i osobe koje su u vezama visoke razine obvezivanja značajno češće birale emocionalnu, dok su muškarci i osobe u vezama niske razine obvezivanja češće birali seksualnu ljubomoru kao onu koja ih više uznemiruje. Utvrđeno je i da ispitivane varijable značajno doprinose objašnjenju varijanci dviju vrsta ljubomore – uspješno je objašnjeno 31,2% varijance emocionalne i 20% varijance seksualne ljubomore. Također se pokazalo da su spol i razina obvezivanja značajni prediktori sklonosti pojedinoj vrsti ljubomore kod metode prisilnog izbora, pri čemu se vjerojatnost odabira emocionalne ljubomore povećava ako je sudionik ženskog spola, te se povećava s porastom razine obvezivanja. The aim of this study was to define the role of sex, attachment style and relationship status in emotional and sexual jealousy in close relationships. Relationship status was defined as relationship length and level of commitment within it. There were 223 participants, in the age of 20 to 35. All of the participants were in some form of a close relationship at the moment of their participation. According to that, all of the instructions and items within used instruments were adjusted to relate to the current relationship of the participant. These instruments were used: general demographics questionnaire, Experiences in Close Relationship Inventory – short form, forced-choice jealousy measure, and Likert-scale jealousy measures. The results of this study showed that women and subjects in highly committed relationships tend to choose emotional, while men and subjects with low levels of commitment to relationship tend to choose sexual jealousy as more upsetting. It was also found that tested variables significantly contributed to explaining variances of the two types of jealousy – 31,2% of the variance in response to emotional jealousy and 20% of the variance in response to sexual jealousy has been accounted for. In addition, sex and commitment level appeared to be significant predictors of inclination to emotional or sexual jealousy in the forced-choice method. The odds for choosing emotional jealousy as more upsetting than sexual jealousy are higher for women and subjects who are in highly committed relationships.

Istraživanje koje smo proveli potvrdilo je korištenje i učinkovitost igre u razrednoj nastavi. Učitelji razredne nastave igru u nastavi najviše koriste više puta tjedno. Učiteljima su se sljedeće igre pokazale učinkovitima u razrednoj nastavi: igre asocijacija, igre riječima, natjecateljske igre, matematičke igre, križaljke i rebusi. Učenici najviše vole igre asocijacija i natjecateljske igre. Učitelji igre najviše koriste u uvodnom i završnom dijelu sata. Učitelji iz gradova igru koriste u svim školskim predmetima. Učitelji s manje godina staža navode veći broj igara koje su im se pokazale učinkovitima u razrednoj nastavi, dok učitelji s više godina staža znaju i koriste veći broj igara povezanih sa zavičajem u kojem smo istraživanje proveli. Učitelji s visokom stručnom spremom navode veći broj igara koje koriste i koje su im se pokazale učinkovitima u razrednoj nastavi u odnosu na učitelje s višom stručnom spremom. Učitelji s višom stručnom spremom više ističu natjecateljske i zavičajne igre kao one koje koriste u razrednoj nastavi.

Središnja tema ovog rada jesu situacijski utjecaji koji uzrokuju promjenu karaktera dobrih ljudi u zle ljude. Te utjecaje sažeo je P.Zimbardo u pojam Lucifer efekta, a njegovo djelovanje pokazao je svojim poznatim stanfordskim eksperimentom simulacije zatvora (SESZ). U podlozi ovog pojma mnoštvo je različitih grupnih procesa, a ovdje ih je navedeno sedam. Prvi proces, poduzimanje prvog malog koraka, stvara unutarnji pritisak da se od malog nedjela prelazi na sve veća zlodjela. Takvo ponašanje počinitelji sebi i drugima objašnjavaju pomoću druga dva navedena procesa – slijepom poslušnošću autoritetu i difuzijom odgovornosti. Oba ta procesa naizgled oslobađaju počinitelja odgovornosti, čemu pridonosi i četvrti proces – deindividuacija. Ona čini počinitelja anonimnim i dopušta mu da djeluje bez ograničavajućih granica savjesti. Peti proces je dehumanizacija koja oduzima ljudskost potencijalnim žrtvama. Zadnja dva procesa posljedica su „automatskog pilota“ na kojem većina ljudi funkcionira. Radi nepromišljanja dolazi do nekritičkog prihvaćanja grupnih normi, što može rezultirati kršenjem uobičajenih društvenih normi, i do više pasivne inačice istoga – toleriranje zla nedjelovanjem. Međutim, ove situacijske utjecaje moguće je svladati pomoću informiranosti o tome kako djeluju, te razvojem svijesti o sebi, situacijske osjetljivosti i snalažljivosti.

Dat je teoretski osvrt na igru, karakteristike i dobrobit dječje igre, korištenje igre u nastavi. Napravljeno je istraživanje igre u nastavi kod učitelja razredne nastave koji rado koriste igru u nastavi, naročito za motivaciju i za ponavljanje gradiva.

Bolesnici u životnoj dobi od 70 do 74 godine u najvećoj su opasnosti od interakcija jer ih čak 8% uz statin uzima i neki od inhibitora citokroma P 450.