27 research outputs found
GraniÄni sloj ioniziranog plina na rotacijskim tijelima pri postojanju magnetskog polja
This paper studies ionized gas flow in the boundary layer on bodies of revolution. The present magnetic field is normal to a nonporous contour of the body. The governing boundary layer equations are brought to a generalized form by general similarity method. The obtained equations are numerically solved by finite differences method. Based on the obtained solutions, diagrams of distributions of physical qualities in the boundary layer are given. Conclusions of behaviour of these quantities for the studied ionized gas problem are also drawn.Istraživano je strujanje ioniziranog plina u graniÄnom sloju na rotacijskim tijelima. Prisutno magnetsko polje je okomito na neporoznu konturu tijela. Polazne jednadžbe graniÄnog sloja dovedene su na uopÄeni oblik metodom uopÄene sliÄnosti u verziji Saljnikova. Dobivene jednadžbe numeriÄki su rijeÅ”ene metodom konaÄnih razlika. Na osnovu dobivenih rjeÅ”enja prikazani su dijagrami raspodjela fizikalnih veliÄina u graniÄnom sloju. Izvedeni su zakljuÄci o ponaÅ”anju ovih veliÄina kod razmatranog problema strujanja ioniziranog plina
Procjena specijacije kadmija u saliniziranim okoliŔnim uvjetima
PoveÄanje saliniteta i sadržaja elemenata u tragovima u povrÅ”ini tla putem neodgovarajuÄih praksi gospodarenja zemljiÅ”tem (fertirigacija, aplikacija kondicionera tla) predstavlja jednu od najraÅ”irenijih prijetnji sigurnosti i zaÅ”titi hrane u suvremenoj poljoprivredi. Fitodepozicija, kao najznaÄajniji naÄin unosa biotoksiÄnog i neesencijalnog kadmija (Cd) u ljudske namirnice, korespondira pozitivno sa salinitetom rizosfere. PomoÄu kemijsko specijacijskog raÄunalnog pristupa (Visual MINTEQ) procijenjen je biogeokemizam Cd-kontaminirane (1ĀµM) otopine s razliÄitim razinama (nizak-visok) jednih od najzastupljenijih prirodnih minerala (Na+15-150, Cl- 12-90 i SO42- 1.5-30 mM) u Å”irokom pH (3.5-9.5) rasponu i niskom prisustvu otopljenog organskog ugljika (1 mg DOC/L). Na temelju modeliranih rezultata, koncentracija slobodnog Cd2+ je dominirala u veÄini testiranog pH raspona kod niskog saliniteta, dok su u okruženju srednjeg do visokog saliniteta prevladavale koncentracije Cd-Cl- i Cd-SO4-kompleksiranog sadržaja Cd. NICA-Donnan modeliranjem je potvrÄena važnost Cd-organo-kompleksiranog sadržaja jedino pri viÅ”im pH vrijednostima (>8.0) i nižem salinitetu. Rezultati potvrÄuju da kao posljedica smanjenog otopljenog organskog sadržaja uslijed poveÄanog saliniteta (npr. prirodno salinizirana tla, vode koriÅ”tene za navodnjavanje u poljoprivredi) biogeokemizam Cd u rizosferi može pospjeÅ”iti mobilnost Cd, a time i njegovu fitoekstrakciju od strane navodnjavanih kultura
Evaluation of genetic variance components for some quantitative traits in rapeseed (brassica napus l.)
Three hybrid combinations obtained by crossing six winter rapeseed cultivars were analyzed for the impact of genes with additive and dominant effects and their interactions with inheritance of plant height and first lateral branch height. The linkage among the expected progeny means was checked using the scaling test method (Mather, 1949), while the estimates of genetic effects and mode of inheritance was made by the Generation Mean Analysis (Mather and Jinks, 1982). The additive dominant model did not prove adequate for plant height in all three crosses, and for first lateral branch height in the second and third cross. The inadequacy of the model showed epistatic gene effects were also of large importance in the inheritance of these traits. Duplicate epistasis for plant height inheritance was found in all three cross combinations and for inheritance of height of the first lateral branch in second and third cross combination. However, it should be emphasized that duplicate epistasis among dominant positive genes occurred on plant height inheritance in C1 and C3, and on inheritance of first lateral branch height in C3. Duplicate epistasis among dominant negative genes occurred in C2 on the mode of inheritance of both traits
Prostorna i vremenska raspodela potencijalne ugroženosti podruÄja Vojvodine procesima eolske erozije
Eolska erozija predstavlja znaÄajan vid degradacije obradivih poljoprivrednih zemljiÅ”ta. Prirodni i antropogeni faktori na podruÄju Vojvodine pogoduju nastanku i razvoju intenzivnih vetroerozionih procesa. MeÄu brojnim uzroÄnim faktorima složenog procesa eolske erozije (reljef, klima, zemljiÅ”te, vegetacija, naÄin koriÅ”Äenja zemljiÅ”ta, organizacija zemljiÅ”ne teritorije itd.) u ovom radu se analizira klima, kao agresivna komponenta erozije. Prvenstveno vetar, a zatim padavine i temperature, odnosno njihova nepovoljna koincidencija, direktno ili indirektno utiÄu na potencijalnu opasnost od pojave i razvoja eolske erozije. Stvarna realizacija procesa, tj. produkcija eolskog nanosa, zavisi i od svih ostalih relevantnih Äinilaca. Na osnovu definisanog klimatskog faktora izdvojena su podruÄja i periodi sa razliÄitim stepenom potencijalne ugroženosti i opasnosti od nastanka eolske erozije. Konstatovano je da prema klimatskom faktoru podruÄje Banata može da se smatra 3 do 4 puta ugroženije od ostalih delova Vojvodine. Najintenzivniji erozioni procesi moguÄi su tokom ranog proleÄa (april) i jeseni (oktobar), posebno u izrazito suÅ”nim godinama
IskoriÅ”Äenost prirodnih resursa Vojvodine za navodnjavanje
ZnaÄajne povrÅ”ine plodnog obradivog zemljiÅ”ta dobrih proizvodnih svojstava i raspoložive koliÄine vode, kao najznaÄajniji prirodni resursi i potencijali, Äine da Vojvodina ima povoljne uslove za intenzivniji razvoj i primenu navodnjavanja. TakoÄe, postoje realne potrebe za navodnjavanjem jer zemljiÅ”tu i gajenim biljkama tokom vegetacionog perioda nedostaje oko 100 do 300 mm vode. Sve ÄeÅ”Äe se ispoljava manjak i neodgovarajuÄa unutargodiÅ”nja raspodela atmosferskih padavina. Osnovu vodnih resursa predstavljaju reke Dunav, Tisa i Sava, niz manjih prirodnih vodotoka, osnovna (ukupne dužine 930 km) i detaljna (20.000 km) kanalska mreža koje pružaju moguÄnost zahvatanja dovoljnih koliÄina vode za potrebe navodnjavanja. NajveÄi deo povrÅ”ina navodnjava se vodom iz prirodnih vodotoka i kanala (preko 90%) i to najÄeÅ”Äe veÅ”taÄkom kiÅ”om (80-90%). MeÄu navodnjavanim povrÅ”inama dominiraju oranice i baÅ”te (oko 95%) dok su ostale pretežno pod voÄnjacima (5%). Navodnjavane povrÅ”ine zauzimaju ukupno 20-30 hiljada hektara. Razvojni potencijali su daleko veÄi
Monitoring kvaliteta vode i sedimenta manjih vodotoka u Vojvodini ā primer vodotoka Tatarnica
U radu se analizira stanje kvaliteta vode i sedimenata kanalisanog vodotoka Tatarnica. Ovaj vodotok predstavlja i glavni kanal jednog od sistema za odvodnjavanje, koji je lociran dvadesetak kilometara zapadno od Novog Sada (Vojvodina, Srbija). Kvalitet vode i sedimenta ovog vodotoka, pored ostalog, znaÄajan je zbog toga Å”to se njegove vode koriste za navodnjavanje povrtarskih kultura na okolnim obradivim povrÅ”inama ali i zbog toga Å”to se uliva u Dunav u zoni akvatorije posebne ekoloÅ”ke vrednosti, parka prirode BegeÄka jama. Na osnovu meseÄnog uzorkovanja vode i analize relevantnih indikatora kvaliteta, tokom perioda 2006-2012. godine, prikazani su rezultati sedmogodiÅ”njeg monitoringa kvaliteta vode i sedimenata. Prema veÄini relevantnih parametara kvaliteta, u najveÄem broju uzoraka, voda ima dobar ekoloÅ”ki potencijal. MeÄutim, konstatovana je i povremena pojava vode neodgovarajuÄeg kvaliteta, najÄeÅ”Äe kada je u pitanju organsko zagaÄenje iskazano preko poveÄanih vrednosti bioloÅ”ke i hemijske potroÅ”nje kiseonika (BPK5 i HPK) kod oko 35% uzoraka. Odstupanja od zahtevanog kvaliteta vode konstatovana su i kod ostalih parametara u oko 10-25% uzoraka. Sastav sedimenata, po svim razmatranim parametrima, uglavnom je u granicama koje nemaju negativne posledice na životnu sredinu u kanalu i njegovom okruženju
Upravljanje kvalitetom u organskoj proizvodnji i preradi mleka
Organic production of milk and milk products with the mark of 'organic products' requires certain acquaintance of some rules that have been established through the organic production standards. Producers as well as the processors must completly and timely be informed about the necessary conditions and how to manage in accordance with organic production standards. Proper quality managing in farm milk production as well as in the milk processing generate some preconditions for manufacturing of milk products that are more healthy, high nutrition valued, with better flavor properties and which positively influence the sustainable development of the human society, environmental protection and better social quality.Organska poljoprivreda predstavlja sveukupan sistem upravljanja poljoprivredom i proizvodnjom hrane. Kombinovan sa zaÅ”titom životne sredine uz oÄuvanje biodiverziteta i prirodnih resursa je osnova za kvalitetnu i bezbednu hranu, socijalnu sigurnost i održivi razvoj. U ovom radu istraživanje je skoncentrisano na specijalne teme, taÄnije reÄeno na bezbednost mleka na farmama koje rade po principima organske proizvodnje, zatim na kvalitet mleka i kontrolu kvaliteta. Sumirani su koraci uvoÄenja HACCP sistema na porodiÄnim farmama koje su specijalizovane za proizvodnju sirovog mleka. Kvalitet sirovog mleka je osnovni preduslov za proizvodnju kvalitetnih mleÄnih proizvoda a kako je praksa u Srbiji malo drugaÄija od zahteva EU, njegova važnost Äe biti joÅ” veÄa posle ulaska u EU. Rezultati istraživanja na oglednim farmama i mlekari u JužnobaÄkom okrugu (FruÅ”ka gora) su dobijeni u okviru projekta BTN 20100. Okolnosti proizvodnje bile su dosta dobre, s obzirom da je podruÄje FruÅ”ke gore dosta izolovano i izgleda kao prava prirodna oaza. Nema zagaÄenja iz okoline, stoka dosta vremena provodi na paÅ”njacima, rasni sastav je veÄinom domaÄe Å”areno goveÄe koje je otporno i zdravo, voda je dobrog kvaliteta i ima niz drugih predispozicija za organsku stoÄarsku proizvodnju. Ova istraživanja imala su nekoliko razliÄitih koraka u upravljanju kvalitetom, od ispitivanja postojeÄih uslova, zatim ulazak u period konverzije i priprema za organsku proizvodnju
Alport's syndrome and benign familial haematuria: light and electron microscopic studies of the kidney
INTRODUCTION Hereditary nephropathy is clinically characterized by the familial occurrence in successive generations of progressive haematuric nephritis and neural hearing loss. Hereditary nephropathy of Alport's syndrome (AS) and benign familial (recurrent) haematuria (BFH) are morphologically characterized by specific and diagnostically important thickening and splitting of lamina densa of the glomerular basement membranes. Those lesions can be recognized only by electron microscopy. Hereditary nephritis is usually present clinically with haematuria, and new mutations without a family history of haematuria. It is therefore important to differentiate hereditary nephritis from BFH and no familial haematuria. Thus, electron microscopy is essential in diagnosis of haematuria. OBJECTIVE The aim of this study was to describe, by light microscopy, constellation of renal alterations by which hereditary nephropathy can be recognized with high probability as well as to compare the diagnostic validity of the findings observed by light and electron microscopy in AS and BFH. METHOD We examined 48 renal biopsies of the patients with hereditary nephoropathies by light and electron microscopy. Tissue samples were fixed in buffered paraformaldehyde and embedded in paraffin for long-term preservation. For the electron microscopy analysis, the following fixation in 4% glutaraldehyde tissue was postfixed in 1% osmium tetroxide.Thereafter, the following dehydration procedure tissue slices were embedded in epon. RESULTS Our results demonstrated that the interstitial foam cells, foetal-like glomeruli, minimal glomerular abnormalities with stain less intense in basement membranes, mild irregular mesangial widening, focal thickening of Bowman's capsule, foci of dilatation tubules, tubular ectasia and atrophy, erythrocyte tubules casts were present in hereditary nephritis. Additionally, light microscopic biopsy findings in patients with BFH were either normal or revealed minor changes (e.g. increased mesangial matrix). All biopsies were reevaluated by electron microscopy and ultrastructural findings confirmed the diagnosis of hereditary nephropathies. CONCLUSION The findings observed by light microscopy represent an important step that leads to a definitive diagnosis of AS and BFH. The definitive diagnosis, however, depends on electron microscopy
Water for all : Proceedings of the 7th international scientific and professional conference Water for all
The 7th International Scientific and Professional Conference Water for all is organized to honour the World Water Day by the Josip Juraj Strossmayer University of Osijek, European Hygienic Engineering & Design Group (EHEDG), Danube Parks, Croatian Food Agency, Croatian Water, Faculty of Food Technology Osijek, Faculty of Agriculture in Osijek, Faculty of Civil Engineering Osijek, Josip Juraj Strossmayer University of Osijek Department of Biology, Josip Juraj Strossmayer University of Osijek Department of Chemistry, Nature Park āKopaÄki ritā, Osijek- Baranja County, Public Health Institute of the Osijek- Baranja County and āVodovod-Osijekā -water supply company in Osijek. The topic of World Water Day 2017 was "Wastewater" emphasizing the importance and influence of wastewater treatments on global environment. The international scientific and professional conference Water for all is a gathering of scientists and experts in the field of water management, including chemists, biologists, civil and agriculture engineers, with a goal to remind people about the significance of fresh water and to promote an interdisciplinary approach and sustainability for fresh water resource management. The Conference has been held since 2011. About 300 scientists and engineers submitted 95 abstracts to the 7th International Scientific and Professional Conference Water for all, out of which 33 was presented orally and 62 as posters. 47 full papers were accepted by the Scientific Committee. 38 full papers became the part of the this Proceedings while 9 papers were accepted for publication in Croatian Journal of Food Science and Technology and Electronic Journal of the Faculty of Civil Engineering Osijek - e-GFOS