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Primjena plazma tehnologije u poljoprivredi provodi se tretiranjem sjemena ili biljaka hladnom plazmom (NTP) ili plazmom aktivirane vode (PAW). Različit reaktivni spojevi potencirani plazmom djeluju kao signalne molekule u metabolizmu biljaka, pokreću aktivnost gena koji reagiraju na stres u biljkama ili služe kao hranjive tvari. Cilj ovoga rada je prikazati učinak tretiranja hladnom plazmom na promjene koje dovode do poboljšanja rasta poljoprivrednih kultura. Rezultati istraživanja ukazuju na različiti odgovor poljoprivrednih kultura na tretman plazmom. Zbog toga je potrebno provoditi daljnja istraživanja kako bi se utvrdio optimalan utjecaj plazme na biljke.

Spavanje predstavlja biološki proces nužan za očuvanje zdravlja i obavljanje svakodnevnih funkcija. Doktori dentalne medicine često su prvi među zdravstvenim djelatnicima koji primijete simptome poremećaja spavanja ili im se pacijenti sami požale na njih. Stanja poput sleep apneje, bruksizma i orofacijalne boli ozbiljno narušavaju pacijentovu kvalitetu života i dovode do teških posljedica. Poremećaji spavanja zahtijevaju multidisciplinaran pristup, a veliku ulogu u ranom prepoznavanju, prevenciji i terapiji imaju doktori dentalne medicine. Pri tome je potrebno razumjeti neurobiološke mehanizme u podlozi patoloških zbivanja povezanih s poremećajima spavanja i disanja, razjasniti neuromuskularnu povezanost žvačnog sustava, prepoznati etiološke i rizične faktore te pružiti pacijentima odgovarajuću terapiju u suradnji s drugim medicinskim djelatnicima. Sleeping is a biological process essential for preserving health and carrying out everyday bodily functions. Dental practitioners are often the first health workers to detect – or hear patients complain of – symptoms of sleeping disorders. Conditions such as sleep apnea, bruxism, or orofacial pain can seriously impact a patient’s quality of life and may lead to serious complications. Treating sleep disorders requires a multidisciplinary approach in which dental practitioners play a vital role in early detection, prevention, and treatment. This demands an understanding of the neurobiological mechanisms that underlie pathological occurrences connected with sleep disorders and breathing, a clarification of the neuromuscular coherence of the masticatory system, an identification of etiological and risk factors, and the right treatment in cooperation with other medical practitioners.

U radu su prikazani rezultati istraživanja analize održavanja poljoprivredne tehnike u eksploataciji. Obavljen je intervju sa rukovateljima (81) koji upravljaju s istraživanom poljoprivrednom tehnikom, a u vidu utvrđivanja provođenja mjera dnevnog i tjednog održavanja. Mjere dnevnog održavanja se u većem dijelu ne provode, a što je suprotno od mjera tjednog održavanja koji se većim dijelom provode. Rukovatelje istraživanih strojeva treba potaknuti i po potrebi poslati ponovno na edukacije kako bi kvalitetnije obavljali mjere održavanja i s time produžili radni vijek poljoprivredne tehnike.

Zinnias are ornamental species which are not demanding for breeding, sunny and warm position with loamy well-drained soil is sufficient. The aim of the research was to compare the growth and development of Zinnia (Zinnia elegans Jacq.) in a sunny place, during spring and summer period, in three substrates of various physical and chemical properties (Potgrond H, Florabella and soil). The seeds were sown in PVC containers (Pöpellmann TEKU (EP 2128/20) 28 cm x 21cm x 6 cm) with 20 sowing places (volume 150 ml). After developing four leaves, plants were transplanted into PVC pots (Φ 9 cm) filled with the same substrate. The pot trial was conducted as a randomized complete design with four repetitions. Four weeks later on the developed plants, following values has been measured: plant mass, plant height, plant height above ground, mass of the above-ground part of the plant and the number of leaves. Plants grown in Florabella substrate had higher values than plants grown in Potgrond substrate and soil. Statistically significant difference (P≤0.01) has been found between the values of plants grown in soil and substrates Potgrond H and Florabella.

Maize (Zea mays L.) grain yield largely depends on the amount of plant-available water, nutrients, climatic conditions, soil, and genotype. The grain yield formation is closely related to yield components. The field study was set up near Osijek (2020) on silty clay soil with, loamy texture. The different treatments consisted of two irrigation treatments (a1=irrigated ; a2=rainfed), and two maize hybrids (b1=ossk515 ; b2=po216). Surface irrigation was conducted with the use of furrows, while the soil water content was measured with tensiometers placed at a depth of 30 cm on each irrigation treatment. Net irrigation was 280 mm which completely compensated the crop water requirements on irrigated plots. Significantly (p

The COVID-19 pandemic has significantly affected many segments of human life and activities, including the education system. As a consequence, universities are facing challenges on how to continue with quality teaching where face-to-face classes have opted and remote teaching is introduced. Remote teaching and learning usually carry a stigma of being lower quality than the traditional (face- to-face), which is why it is necessary to evaluate the teaching staff as well as the student experience within remote education. The survey conducted at the Faculty of Agrobiotechnical Sciences Osijek, Republic of Croatia aimed to analyze how students as well as teaching staff were satisfied with remote education during the first wave of coronavirus pandemic. Survey results have shown that most of the students were satisfied with the organization and implementation of remote learning and teaching as well. An interesting observation was the importance of teacher- student interaction as well as the teacher presence during remote education.

With the increasing need for energy, energy studies to be obtained from waste gain importance. In this study, it has been tried to determine the amount of biogas energy that can be obtained from olive pomace (pirina), which is produced by processing oil olives. Numerical maps of pirina amounts and potential biogas energy values and location maps of the proposed pirina processing plant were created. The necessary calculations were made by comparing the obtained results with the relevant literature information. In the study, the current potential biogas energy amount was calculated, maps were created and the electricity and gasoline energy equivalent levels of this energy were tried to be calculated using the 2015-2019 data of the Mediterranean, Aegean and Marmara Regions. The total potential amount of pirina in the research area is 1853375.7 tons and the potential biogas energy amount that can be obtained is 33360762.4 MJ. Pirina, which is the production waste after pressing the olives for oil, can be used for energy production. By using pirina to obtain biogas energy, both the utilization of pirina and the development of the regions will be provided.

Maize seed is during germination and cropping in the open under the influence of different agroecological factors, so high yields will be achieved mainly by sowing quality high vigor seeds. The aim of this research was to determine maize seed vigor by laboratory methods (mass of 1000 seeds, germination energy (GE), standard germination (SG), electrical conductivity (EC) and cold test (CT)) and at the same time examine the influence of genotype of three maize hybrides. The experiment was set up in four repetitions with 50 seeds for each method. A significant difference (P≤0.01) was found between the masses of 1000 seeds of the analyzed hybrids (314g, 307g, 252g). The energy of germination (66%, 63%, 61%), standard germination (94%, 95%, 91%) and cold test (87%, 97%, 83%) did not differ significantly. The determined values of electrical conductivity (7,96 μScm-1g-1, 7,16 μScm-1g-1, 5,23 μScm-1g-1) were significantly (P≤0.01) influenced by hybrids. The analyzed seed was of satisfactory quality or vigor, and the influence of genotype was determined in seeds tested by electrical conductivity method., Sjeme kukuruza je tijekom klijanja i nicanja na otvorenom pod utjecajem različitih agroekoloških faktora pa se visoki prinosi mogu postići prije svega sjetvom kvalitetnog sjemena visokog vigora. Cilj ovoga istraživanja bio je odrediti vigor sjemena kukuruza laboratorijskim metodama (masa 1000 sjemenki, energija klijanja, standardna klijavost, električni konduktivitet i cold test) te ujedno ispitati utjecaj genotipa tri hibrida kukuruza. Pokus je postavljen u četiri repeticije s 50 sjemenki za svaku metodu. Utvrđena je značajna (P≤0,01) razlika između masa 1000 sjemenki analiziranih hibrida (314g, 307g, 252g). Energija klijanja (66%, 63%,61%), standardna klijavost (94%, 95%, 91%) i cold test (87%, 97%, 83%) nisu se značajno (P≤0,01) razlikovali. Utvrđene vrijednosti električnog konduktiviteta (7,96 μScm-1g-1, 7,16 μScm-1g-1, 5,23 μScm-1g-1) bile su pod značajnim (P≤0,01) utjecajem hibrida. Analizirano sjeme imalo je zadovoljavajuću kvalitetu odnosno vigor, a utjecaj genotipa utvrđen je kod sjemena testiranog metodom električnog konduktiviteta.

The spring field pea is one of the most important coarse legumes. This study was carried out to investigate the response of a spring field pea variety to three plant densities (50, 100, and 150 plant m-2) during the 2017 and 2019 growing seasons in eastern Croatia. The field study was set up as a Randomized Complete Block Design (RCBD) in four replications. The results have demonstrated a significant effect of the plant densities and the growing seasons on the seed yield and on the following yield components: plant height and the number of pods/plant. The effect of plant densities on the number of seeds/pod and the thousand-seed weight was not significant. As for a growing season, the highest seed yield, plant height, the number of pods/plant were obtained in the second growing season. Furthermore, a maximum seed yield was recorded at the 150-plant m-2 plant density. This study has demonstrated that planting the spring field pea at different plant densities significantly modifies the spring field pea yield, plant height and number of pods/plant., Jari stočni grašak jedna je od najznačajnijih krupnozrnih mahunarki. Ovo je istraživanje provedeno kako bismo vidjeli reakciju utjecaja različitih gustoća sjetve na jari stočni grašak tijekom dvaju vegetacijskih ciklusa 2017. i 2019. godine u istočnome dijelu Republike Hrvatske. Pokus je postavljen po RCBD sustavu u četiri ponavljanja. Rezultati pokazuju značajan utjecaj gustoće sjetve i godina istraživanja na prinos zrna i većinu komponenata prinosa: visinu biljke i broja mahuna po biljci, osim broja zrna po mahuni i mase tisuću zrna, gdje gustoća sjetve nije statistički značajno utjecala na razlike u vrijednostima istraživanih svojstava. Najveće vrijednosti prinosa zrna, visine biljke i broja mahuna po biljci ostvarene su u drugoj godini istraživanja. Najveći prinos zrna zabilježen je pri gustoći sjetve od 150 biljaka/m2. Istraživanje pokazuje da različite gustoće sjetve značajno modificiraju/utječu na visinu prinosa zrna i komponente prinosa jaroga stočnog graška.

The aim of the study was to determine allelopathic potential of weed root exudates on germination and growth of crops. Field poppy (Papaver rhoeas L.), scentless mayweed (Tripleurospermum inodorum (L.) C.H. Schultz) and redroot pigweed (Amaranthus retroflexus L.) seedlings were grown in soil until 3-leaf stage. After their removal, the soil was re-sown with seeds of barley, soybean and oil pumpkin. The results of the experiment showed that field poppy and scentless mayweed root exudates stimulated root and shoot length, and fresh weight of barley seedlings up to 16.2%, 13.4% and 34.6%, respectively. Redroot pigweed root exudates showed no significant effect on emergence and growth of soybean and oil pumpkin.

The aim of the paper was to evaluate allelopathic effects of weed species Johnsongrass (Sorghum halepense) and black nightshade (Solanum nigrum) on germination and early growth of sugar beet. Petri dish experiment with water extracts prepared from different plant parts of weeds in 1, 5 and 10% concentrations and pot experiment with weed residues in rates of 10, 20 and 30 g/kg were conducted. Allelopathic potential was determined through germination, root and shoot length, and fresh and dry weight of sugar beet seedlings. Water extracts from various plant parts showed significant inhibitory potential, up to 100%, on germination and growth of sugar beet. Lower extract concentration promoted shoot length up to 35.5%. Johnsongrass residues showed negative effect on shoot length, fresh and dry weight of seedlings, especially in treatment with 30 g/kg residue rate. Contrary, black nightshade residues promoted sugar beet growth. Besides concentration/rate, allelopathic effect was dependent on extraction method, growth media and plant part.

U ovom radu obuhvaćeno je istraživanje vještina programiranja učenika Srednje škole Zvane Črnje Rovinj, smjer tehničar za računalstvo. Istraživanje je obuhvaćalo učenike svih razreda srednje škole. Provedbom istraživanja ispitani su stavovi učenika za predmet „Algoritmi i programiranje“ te su putem testa testirane njihove vještine programiranja. Na temelju dobivenih podataka provedena je detaljna analiza općeg znanja i vještina programiranja, usporedba rezultata nižih i viših razreda, usporedba stavova o predmetu i vještina programiranja te usporedba prosječne prolazne ocjene ispitanika s njegovim rezultatima na zadanom testu. Temeljem dobivenih rezultata date su prijedlozi za poboljšanje vještina programiranja učenika Srednje škole Zvane Črnje Rovinj. This paper presents the analysis of learning and programming skills of student in High School Zvane Črnja Rovinj, course computer technician. Students from all grades participated in the research. In this research, the attitudes of students were examined for the subject “Algorithms and programming”. Also, the research includes programming skills that were tested using a specific test. Based on the obtained data, the detailed analysis performed. This analysis includes a comparison of programming skills and knowledge between grades in school, comparison of attitudes related to subject and comparison of student’s average grade with results on the given test. Based on the results obtained, proposals for improving the skills of programming are given.

Primjena IC termografije u detekciji vodnog stresa u biljnoj proizvodnji prezentirana je sa svojim prednostima i manama. Izlaganje je dalo uvid u dosadašnji razvoj na području vodnog stresa i infracrvene termografije. Poseban osvrt napravljen je na ograničenja, fizikalno ponašanja IC detektora i praktičnu aplikaciju metode.

U cilju proučavanja fotokemijskog ponašanja derivata o-divinilbenzena, Wittigovom reakcijom sintetiziran je 2-benzofurilni-derivat o-divinilbenzena 1. Novosintetizirani derivat 1 podvrgnut je fotokemijskim reakcijama u kiselom mediju kako bi se ispitao utjecaj pH na reakcijski mehanizam. Reakcije osvjetljavanja početnog spoja 1 provedene su pri 350 nm te je dobiveno 5 produkata. Benzobiciklo[3.2.1]oktadienski fotoprodukt 3 i dimerni derivat 6 dobiveni su i u prethodnim istraživanjima u neutralnom mediju, dok su ciklizacijski produkt 2 i stereoizomerni spojevi 4 i 5, koji su nastali kao posljedica otvaranja furanske jezgre, potpuno novi spojevi. Dobiveni spojevi su izolirani te spektroskopski okarakterizirani. In order to study photochemical behaviour of o-divinylbenzene derivatives, 2-benzofuryl-derivative o-divinylbenzene 1 was synthesized by Wittig reaction. New synthesized derivative 1 was subjected to photochemical reactions in acidic media in order to examine influence of pH to reaction mechanism. Reactions of irradiation of initial compound 1 were carried out on 350 nm and it was obtained 5 products. Benzobicyclo[3.2.1]octadiene photoproduct 3 and dimer derivative 6 were obtained also in previous researches in neutral media. On the other side, cyclization product 2 and stereoisomers 4 and 5, which were formed as result of furan ring opening, are new compounds. Obtained compounds were isolated and spectroscopic characterized.

Plastičnost je tla područje konzistencije tla, odnosno predstavlja promjenu stanja tla zbog različite vlažnosti tla djelovanjem vanjskih sila. Konzistencija određuje veličinu otpora koje tlo pruža pri obradi, stoga je cilj istraživanja utvrditi optimalno stanje vlažnosti tla za obradu te utjecaj fizikalnih i kemijskih svojstva oraničnih horizonata na plastičnost tla, kao jednog od svojstava konzistencije. Istraživanje je provedeno na tri različita tipa tla: aluvijalnome, lesiviranome te na ritskoj crnici. Utvrđene su statistički značajne razlike između svih istraživanih tipova tala i to za sadržaj čestica gline, gustoću pakiranja, aktualnu i supstitucijsku kiselost, kation-ski izmjenjivački kapacitet tla te sadržaj kalcija. Također, utvrđene su statistički značajne razlike između istraživanih tipova tala za donju granicu plastičnosti, gornju granicu plastičnosti te indeks plastičnosti. Prosječna utvrđena vrijednost donje granice plastičnosti, kao važnog elementa za određivanje optimalnoga trenutka obrade tla, iznosila je 18, 9% mas. na aluvijalnome tlu, 24, 0% mas. na lesiviranome tlu, dok je na ritskoj crnici iznosila 28, 6% mas. Vrlo značajnu korelaciju pozitivnoga smjera s granicama plastičnosti pokazali su humus, glina, KIK, sitni prah, magnezij, natrij i kalcij, dok su vrlo značajnu korelaciju, ali negativnoga smjera, pokazali hidrolitička kiselost, krupni pijesak, sitni pijesak i krupni prah. Kreiranim regresijskim modelima može se procijeniti optimalno stanje vlažnosti tla za obradu na temelju osnovnih svojstava tala. Preciznost modela značajno se povećava uvođenjem većega broja fizikalnih i kemijskih svojstva tla, a dopunsku preciznost modela mogu povećati podatci o tipu tla.

Osciliranje uroda poljoprivrednih kultura je uobičajeno u poljoprivrednoj proizvodnji na koju utječu brojni čimbenici. Vrlo je važno kontrolirati što veći broj čimbenika kako bi se osciliranje svelo na najmanju moguću mjeru. Brojna istraživanja ukazuju da urodi važnijih poljoprivrednih kultura uglavnom najviše variraju kao posljedica nepovoljnih klimatskih prilika unatoč primjenjenoj standardnoj agrotehnici. Odvođenje suvišne vode i navodnjavanje su uglavnom vrlo bitne mjere kojima možemo stabilizirati urode i kakvoću poljoprivrednih kultura. Prioritet u navodnjavanju trebaju imati sjemenski usjevi i dohodovne kulture, a naglasak treba biti na stručnosti, štednji energije i vode, održivom gospodarenju tlom, vodom i okolišem. Reguliranje vodnoga režima tla i kontrola sadržaja vode u tlu uvijek treba biti u fokusu razvoja poljoprivrede prioritetni zadatak.

U ovom radu dan je uvid u teoriju kaosa koja se pojavljuje kao nova znanost dvadesetog stoljeća uz druge dvije velike znanstvene teorije, kvantnu teoriju i teoriju relativnosti. Na početku rada objašnjava se podrijetlo riječi i značenje pojma kaosa te primjena teorije kaosa u svakodnevnom životu, medicini, psihologiji te ekonomiji. Središnji dio rada posvećen je prikazu primjera kaotičnih sustava u znanosti i inženjerstvu, s posebnim naglaskom na matematičku karakterizaciju kaosa. We present an insight into the chaos theory, which is emerging as a new scientific theory of the twentieth century, together with quantum theory and the theory of relativity. At the beginning of the text the origin and the meaning of the word chaos is explained, as well as the application of chaos theory in everyday life, medicine, psychology and economics. The central part presents examples of chaotic systems in science and engineering, with special emphasis on the mathematical characterization of chaos.