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21.
Ecological evaluation of aquatic and terrestrial subterranean fauna in a karst cave
Peter Kozel, 2018, doctoral dissertation

Abstract: Studies on environmental parameters−subterranean fauna relationship and spatial and temporal patterns of subterranean fauna have dealt with either aquatic or terrestrial faunas. So far, no simultaneous ecological evaluation of aquatic and terrestrial faunas has been performed. To address this issue, we conducted a pilot study dealing in parallel with these two faunas in the cave Zguba jama near Postojna, Slovenia, applying monthly sampling over one year. Aquatic fauna was sampled from permanent water drips, and terrestrial fauna by visual inspection and advanced baited pitfall trapping, along with recording the main abiotic parameters. In percolating water, we recorded aquatic fauna, Copepoda being the dominant taxon, and species-rich troglobiotic fauna, which most probably coexist with aquatic species in a semi-aquatic epikarst environment. Analyses revealed that temperature, distance from the entrance and ceiling thickness are the most important parameters that influence the presence of stygobionts; higher values of these parameters result in a higher probability of the presence of stygobionts in percolation water. The recorded spatial distribution of stygobionts varied distinctly among the sampling sites. This indicates that fauna in sampled drips originated from aquatic or semiaquatic epikarst microhabitats, being completely or nearly completely separated from each other, and probably varied according to environmental characteristics. The temporal pattern of the stygobiotic fauna dynamics presumably occurred because of variable water flow rates and the specific physical and chemical characteristics of the water. The abundance of troglobionts showed distinctive spatial distribution pattern over the seasons. In spring and summer, the highest abundances and the highest probability of presence were found near the entrance. In autumn and winter, unfavorable conditions in the entrance zone most likely triggered the migration of troglobionts towards the climatically more stable deep cave zone, and from the cave into the adjacent fissure network. The highest abundance of troglobionts was found at 7–9°C and relatively high ground substrate moisture. Additionally, we found a higher probability of the presence of troglobionts in cave sections with a larger passage cross-section size, which is probably due to the greater variability of microhabitat types in spacious cave sections. In addition, the higher probability of presence relates to higher substrate pH. One potential explanation for this could be that the specific microorganism communities present in such conditions support the nutritional needs of troglobionts. Most troglobiotic species preferred the deep cave zone where the highest species richness and diversity were also observed. Species richness, abundance and diversity of troglophiles and trogloxenes were highest in the entrance zone and showed relatively similar patterns within the cave. However, troglophiles were more abundant in the transition zone and the initial part of the inner zone. The temporal pattern of trogloxenes and presumably of most troglophiles occurred because of migration between the surface and the cave. The probability of the presence of trogloxenes was highest in the entrance zone and in winter, owing to massive overwintering in the cave. A modified technique of pitfall trapping by placing traps in two parallel sets, a ground and an upper one along the cave, resulted in recording greater species diversity in comparison with the traditional method, i.e., ground pitfall trapping alone. It turned out that such sampling contributes at the same time to both more effective and less invasive inventory of subterranean fauna. The dynamics of relative abundance and species richness of stygobionts and troglobionts within the cave showed partly comparable annual patterns. Nevertheless, our findings point toward the need for a long-term and more detailed study in future to address this question properly.
Keywords: biological inventories, epikarst fauna, faunal dynamics, microhabitats, stygobionts, troglobionts, troglophiles, trogloxenes, Zguba jama
Published in RUNG: 16.02.2018; Views: 4579; Downloads: 315
.pdf Full text (5,25 MB)

22.
PROPERTIES OF REDUCED MEET IDEALS IN LOWER BCK–SEMILATTICES
Hashem Bordbar, Michal Novak, Irina Elena Cristea, Jun young Bae, 2018, published scientific conference contribution

Keywords: BCK–algebra, ideal, lower BCK–semilattice, relative annihilator
Published in RUNG: 12.02.2018; Views: 3571; Downloads: 0
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23.
Composition in EL-hyperstructures
Michal Novak, Irina Elena Cristea, 2017, original scientific article

Keywords: composition hyperring, partially ordered semigroup, hyperstructure
Published in RUNG: 30.10.2017; Views: 3700; Downloads: 0
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24.
Zamenjava obstoječih reaktivnih barvil v tiskarni tekstilne tovarne
Gašper Čefarin, 2017, undergraduate thesis

Abstract: Dandanes se v tekstilni industriji uporabljajo različna barvila za barvanje in tiskanje tekstila. Različne vrste barvil se razlikujejo po kemijskih in fizikalnih lastnostih. Manjše razlike, ki imajo v tiskarni lahko velik pomen, so opazne tudi pri barvilih iste vrste različnih proizvajalcev. Pri izbiri barvil je potrebno biti pozoren na to, kakšen ton ima barva na tekstilu, koliko je barva čista ali motna, ter kakšna koncentracija barvila je potrebna, da dosežemo določeno svetlost barve. Cilj barvanja in tiskanja v tekstilni tovarni je namreč velikokrat tudi poustvariti določeno barvo na tekstilu, ki si jo kupec zaželi. To izvedejo tako, da barvila različnih barv zmešajo skupaj v pravem razmerju, pri čemer uporabljajo različno opremo in računalniške programe. V podjetju Tekstina so se odločili za primerjavo do sedaj uporabljanih barvil s cenejšimi barvili drugega dobavitelja. Menjava barvne palete barvil je proces, ki zahteva svojevrsten projekt ovrednotenja ter medsebojne primerjave barvil različnih proizvajalcev in sicer čimbolj natančno, tako z vidika nastalih barv na tekstilu pri tiskanju, ter s finančnega, tehnološkega in okoljskega vidika. Namen diplomske naloge je prikazati, ali je zamenjava obstoječih reaktivnih barvil z novimi v tiskarni tekstilne tovarne smotrna. V okviru diplomske naloge sem izvedel primerjalni tisk in primerjal nastale barve na tekstilu ter razlike v ceni, vplivih na okolje ter tehnološke lastnosti barvil oziroma kvaliteto barvil obeh dobaviteljev. Ugotovil sem, da bi bila najbolj smotrna menjava treh barvil, ki so v tiskarni podjetja količinsko najbolj uporabljana, menjava ostalih barvil pa zahteva dodatno presojo s strani izkušenih ljudi in strokovnjakov na tem področju.
Keywords: tekstilna industrija, tiskarna, tiskanje, reaktivna barvila, barvna paleta, zamenjava dobavitelja
Published in RUNG: 25.09.2017; Views: 5281; Downloads: 243
.pdf Full text (2,84 MB)

25.
Overview on the height of a hyperideal in Krasner hyperrings
Hashem Bordbar, Irina Elena Cristea, Michal Novak, 2017, published scientific conference contribution abstract

Keywords: Krasner hyperring, prime hyperideal, Noetherian hyperring
Published in RUNG: 30.08.2017; Views: 3792; Downloads: 0
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26.
Contribution of Cu and Zr to the Properties of TiO2 for Photocatalytic Water Treatment
Olena Pliekhova, Iztok Arčon, Nataša Novak Tušar, Urška Lavrenčič Štangar, 2017, published scientific conference contribution abstract

Keywords: Photocatalysis, water treatment, surface modification, durability
Published in RUNG: 23.08.2017; Views: 4578; Downloads: 0
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27.
Role of Surface Cu-O-Zr Sites in the Photocatalytic Activity of TiO2 Nanoscale Particles
Olena Pliekhova, Iztok Arčon, Nataša Novak Tušar, Urška Lavrenčič Štangar, 2016, published scientific conference contribution abstract

Keywords: Photocatalysis, Titanium dioxide, Copper, Zirconia, co-doping, EXAFS, XANES
Published in RUNG: 23.08.2017; Views: 4711; Downloads: 0
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28.
HEIGHT OF HYPERIDEALS IN NOETHERIAN KRASNER HYPERRINGS
Hashem Bordbar, Irina Elena Cristea, Michal Novak, 2017, original scientific article

Abstract: Inspired by the classical concept of height of a prime ideal in a ring, we proposed in a precedent paper the notion of height of a prime hyperideal in a Krasner hyperring. In this note we first generalize some results concerning the height of a prime hyperideal in a Noetherian Krasner hyperring, with the intent to extend this definition to the case of a general hyperideal in a such hyperring. The main results in this note show that, in a commutative Noetherian Krasner hyperring, the height of a minimal prime hyperideal over a proper hyperideal generated by n elements is less than or equal to n, the converse of this claim being also true. Based on this result, it can be proved that the height of such a prime hyperideal is limited by the height of a corresponding quotient hyperideal.
Keywords: Krasner hyperring, prime/maximalhyperideal, Noetherian hyperring, height of a prime hyperideal
Published in RUNG: 01.06.2017; Views: 4570; Downloads: 0
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29.
A class of hyperlattices induced by quasi-ordered semigroups
Irina Elena Cristea, Michal Novak, Stepan Krehlik, 2017, published scientific conference contribution

Abstract: In this paper we study hyperstructure generalizations of lattices. We give conditions for EL-semihypergroups to be H_v-semilattices, hypersemilattices or hyperlattices. We also study some of their special elements.
Keywords: join hyperlattice, hyperlattice, hypersemilattice, quasi-ordered semigroup
Published in RUNG: 06.02.2017; Views: 3990; Downloads: 1
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30.
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