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BELUGA Huso huso (Linnaeus, 1758)
No full textMORUNA
Huso huso (Linnaeus, 1758)
BELUGA
Huso huso (Linnaeus, 1758)Moruna je nastanjivala Crno, Kaspijsko, Azovsko i Jadransko
more i njihove basene. Iščezla je iz Jadranskog i Azovskog mora
zbog prelova i izgradnje brana na rekama u koje migrira zbog mresta.
Jedina preostala prirodna populacija u Kaspijskom moru migrira
u reku Ural, a jedina preostala populacija u Crnom moru migrira
u Dunav, dok su sve ostale populacije skoro sasvim nestale, takođe
zbog prelova i izgradnje brana. Pre izgradnje đerdapskih brana jedinke
su migrirale uzvodno do Nemačke, a ulazile su i u veće pritoke
Dunava (Savu i Dravu). Nakon izgradnje brana, njihovo prisustvo
beleži se samo nizvodno od brane „Đerdap II” (Slika 68).
The beluga inhabited the Black, Caspian, Azov and Adriatic Seas and
their basins. In the Adriatic Sea and the Sea of Azov it has disappeared
due to overfishing and the construction of dams in the rivers where it
migrates to spawn. The only remaining natural population in the Caspian
Sea is migrating to the Ural River, and the only remaining population
in the Black Sea is migrating to the Danube, while all other populations
have almost completely disappeared, also due to overfishing and the
construction of dams. Before the construction of the Đerdap dams, individuals
migrated upstream to Germany and entered the larger tributaries
of the Danube (Sava and Drava). After the construction of the dams,
they were only recorded downstream of the dam "Đerdap II" (Figure 68)
Effects of Silicon Concentration and Synthesis Duration onLignin Structure: A Spectroscopic and Microscopic Study
No full textSilicon (Si) is a highly abundant mineral in Earth's crust. It plays a vital role in plant growth, providing mechanical support,
enhancing grain yield, facilitating mineral nutrition, and aiding stress response mechanisms. The intricate relationship between
silicification and lignin chemistry significantly impacts cell wall structure. Yet, the precise influence of Si on lignin synthesis
remains elusive. This study investigated the interaction between Si and lignin model compounds during in vitro synthesis.
Employing spectroscopic and microscopic analyses, we delineated how Si concentrations modulate lignin polymerization dynamics,
particularly affecting molecular conformation and aggregation behavior over time. Fluctuations in the polymer structure
are directly related to both the synthesis time and the concentration of silica. Our results demonstrate that lower Si concentrations
promote the aggregation of lignin oligomers into larger particles, while higher concentrations increase the possibility of
oligomer repulsion, thus preventing particle growth. These findings elucidate the intricate interplay between Si and lignin, which
is crucial for understanding plant cell wall structure and stress resilience. Moreover, the results provide insights for developing
lignin-silica
materials with increasing applications in industry and medicine
Influence of Fe3+ ions and citrate in the photodegradation of levofloxacin in water solution at pH 5
No full textLevofloxacin (LVX) is an antibiotic from the fluoroquinolone family, often used to treat bacterial infections. Its extensive use can lead to environmental contamination, raising significant health concerns for both humans and ecosystems [1]. The influence of citrate and the presence of ferric ions on photosensitivity of LVX to UV-A and UV-B irradiation was investigated by UV-Vis and fluorescence spectroscopy in water at pH 5. Cyclic voltammetry was applied to examine the effect of coordination between Fe3+ ions and LVX on their redox properties in water at pH 5 in the presence of citrate. Results from UV-Vis and fluorescence spectroscopy demonstrated that significant spectral changes occur when the LVX:Fe:citrate 1:3:1 molar ratio, indicating the photodegradation of LVX. Understanding the stability of LVX can aid in the development of effective methods for its removal, which is crucial for reducing pollution and protecting the environment
Functional iridoid synthases from iridoid producing and non-producing Nepeta species (subfam. Nepetoidae, fam. Lamiaceae)
No full textIridoids, a class of atypical monoterpenes, exhibit exceptional diversity within the Nepeta genus (subfam. Nepetoidae, fam. Lamiaceae).The majority of these plants produce iridoids of the unique stereochemistry, with nepetalactones (NLs) predominating; however, a few Nepeta species lack these compounds. By comparatively analyzing metabolomics, transcriptomics, gene co-expression, and phylogenetic data of the iridoid-producing N. rtanjensis Diklić & Milojević and iridoid-lacking N. nervosa Royle & Bentham, we presumed that one of the factors responsible for the absence of these compounds in N. nervosa is iridoid synthase (ISY). Two orthologues of ISY were mined from leaves transcriptome of N. rtanjensis (NrPRISE1 and NrPRISE2), while in N. nervosa only one (NnPRISE) was identified, and it was phylogenetically closer to the representatives of the Family 1 isoforms, designated as P5βRs. Organ-specific and MeJA-elicited profiling of iridoid content and co-expression analysis of IBG candidates, highlighted NrPRISE2 and NnPRISE as promising candidates for ISY orthologues, and their function was confirmed using in vitro assays with recombinant proteins, after heterologous expression of recombinant proteins in E. coli and their His-tag affinity purification. NrPRISE2 demonstrated ISY activity both in vitro and likely in planta, which was supported by the 3D modeling and molecular docking analysis, thus reclassification of NrPRISE2 to NrISY is accordingly recommended. NnPRISE also displays in vitro ISY-like activity, while its role under in vivo conditions was not here unambiguously confirmed. Most probably under in vivo conditions the NnPRISE lacks substrates to act upon, as a result of the loss of function of some of the upstream enzymes of the iridoid pathway. Our ongoing work is conducted towards re-establishing the biosynthesis of iridoids in N. nervosa
Influence of plastic waste on soil properties and microbial activity in three river basins in Serbia
No full textMicroplastic (MP) accumulation in soil may have a detrimental impact on soil quality and biota.
The goal of this study was to reveal the impact of microplastic particles on oil chemical,
physical and biological characteristics. Alluvial soils from three main river basins (Danube,
Morava and Sava) most affected by seasonal flooding were selected in Serbia. Two type rf
land use were studied: forest soil (MP polluted and non-polluted) and agricultural soil (plastic
greenhouse and open crop production). Soil was sampled from two depths 0-15 and 15-30 cm
in 2022. Soil electrical conductivity (EC), pH, CEC, content of total carbon, nitrogen, P20 s, K20,
Cu, Zn, Mn and CaCQ3, particle size distribution, volumetric mass, specific mass and porosity,
basal respiration and microbial activity measured by alkaline trap method were analyzed. The
values of EC and pH were higher in all soil samples from plastic greenhouses compared to the
control samples in both depths at both sites, while the measured values of CEC, carbon,
nitrogen, P2Os. and KiO were higher in samples from the control arable soils. The content of
CaCQ3 was higher in the samples from the greenhouse compared to the control at both depths
at the site in the Sava basin, while it wasn't significantly different in the samples from the
Danube basin. The content of Cu, Zn and Mn was higher in the control samples at both depths
in both sites, except for the sample from a depth of 15-30 cm from the location in the Danube
basin where the Mn content is higher in the greenhouse. No significant difference in volumetric
mass between the samples from the greenhouse and the control samples at both sites was
detected. However, the specific mass, porosity, and particles> 0.02 mm were higher in the soil
from the greenhouse at both sites. The microbial activity expressed by soil respiration at the
Sava basin wasn't significantly different between the plastic house and control arable soil. On
the contrary, in the Danube valley respiration was by 78% higher in the control samples
compared to the samples from the plastic house. In all studied sites soil chemical and biological
properties were significantly affected by the presence of plastic materials in plashc
greenhouses. Generally, polluted sites showed elevated microbial respiration and the rates of
C mineralization. Wild mixed waste deposits contain a variety of organic substrates including
microplastics, which are organic polymers. They can serve as a source of organic carbon for
soil microorganisms under laboratory-controlled conditions with optimal temperature and
humidity. The changes in soil physical parameters are obviously due to the presence of plastic
particles. Further study of differences in the activity of soil microorganisms in polluted and
unpolluted areas is necessary in order to identify the threshold level of MP pollution for the
optimal amount and activity of soil biota, as well as for soil health and fertility
Преглед угрожених врста риба у фауни Србије - Acipenser stellatus (паструга)
No full textNa globalnom nivou, pastruga se smatra kritično ugroženom
vrstom (CR) prema kriterijumima A2bcde (Qiwei, 2010; Mugue et
al., 2022). Na osnovu procene brojnosti populacije na teritoriji Srbije,
pastrugi je dodeljen status kritično ugrožene vrste (CR), prema
kriterijumima C2b. Procenjeno je da je broj polno zrelih jedinki manji
od 250, sa ekstremnim fluktuacijama njihove brojnosti. Veličina
prostora na kome se vrsta pojavljuje (EOO) u Srbiji iznosi 100 km2,
dok je površina naseljavanja (AOO) svega 1 km2
Преглед угрожених врста риба у фауни Србије – Alosa tanaica (azovska haringa)
No full textNa globalnom nivou, azovska haringa ne smatra se ugroženom
vrstom (Freyhof & Kottelat, 2008d). Obim rasprostranjenja (EOO)
i površina naseljavanja (AOO) u Srbiji nisu procenjeni jer je vrsta
nađena na samo jednom lokalitetu. S obzirom da ne postoje neophodni
podaci za direktnu ili indirektnu procenu ugroženosti na
osnovu stanja populacije, azovska haringa za sada ima status vrste
sa nedovoljno podataka o ugroženosti (DD)
Zingel streber
No full textNa globalnom nivou, mali vretenar ne smatra se ugroženom vrstom. U Srbiji, mali vretenar predstavlja ranjivu vrstu (VU). Obim rasprostranjenja ove vrste (EOO) u Srbiji iznosi 55.766 km², dok površina naseljavanja (AOO) iznosi 128 km². Kvantitativna analiza ukazuje na to da je verovatnoća iščezavanja u prirodnom okruženju ≥10% u narednih 100 godina (kriterijum E). Mali vretenar naseljava slivove Dunava i Dnjestra. U Srbiji nastanjuje Dunav, Savu, Tisu, Neru, Južnu Moravu, Zapadnu Moravu, Veliku Moravu, Jadar, Belicu, Kolubaru, Pek i Mlavu.At the global level, the streber is not considered a threatened species. In Serbia, however, it is classified as Vulnerable (VU). The extent of occurrence (EOO) of this species in Serbia is 55,766 km², while the area of occupancy (AOO) is 128 km². A quantitative analysis indicates that the probability of extinction in the wild is ≥10% within the next 100 years (criterion E).
The streber inhabits the Danube and Dniester River basins. In Serbia, it occurs in the Danube, Sava, Tisza, Nera, South Morava, West Morava, Great Morava, Jadar, Belica, Kolubara, Pek, and Mlava rivers
Eudontomyzon mariae
No full textNa globalnom nivou, ukrajinska paklara ne smatra se ugroženom vrstom, međutim, pretpostavlja se da brojnost populacija postepeno opada kao posledica ekonomskog razvoja. Na području Srbije, rasprostranjenje ove vrste je znatno – EOO iznosi 17.360 km², dok je veličina naseljene površine (AOO) fragmentisana i iznosi svega 20 km². Na osnovu IUCN kriterijuma, ukrajinska paklara u Srbiji ima status gotovo ugrožene vrste (NT). Ukrajinska paklara naseljava slivove Baltičkog, Crnog, Egejskog i Kaspijskog mora, a zabeležena je i u gornjem delu sliva Morave (Češka). U Srbiji naseljava reke crnomorskog sliva, Dunav, Drinu, Savu, Mlavu i Crni timok.At the global level, the Ukrainian brook lamprey is not considered a threatened species; however, it is assumed that population numbers are gradually declining as a consequence of economic development. In Serbia, the species has a relatively wide distribution – the extent of occurrence (EOO) is 17,360 km², while the area of occupancy (AOO) is highly fragmented and amounts to only 20 km². According to IUCN criteria, the Ukrainian brook lamprey is classified as Near Threatened (NT) in Serbia.
The species inhabits the drainages of the Baltic, Black, Aegean, and Caspian seas, and has also been recorded in the upper Morava River basin (Czech Republic). In Serbia, it occurs in rivers belonging to the Black Sea basin – the Danube, Drina, Sava, Mlava, and Crni Timok
Exploration of the charge transport mechanism, complex impedance, dielectric/electric modulus and energy storage characteristics of the aloe vera (Aloe Barbadensis Miller) plant
Get PDFComplex impedance spectra at room temperature in the frequency range of 8 Hz—5 MHz were measured on freshly cut leaf sections of the Aloe vera plant by AC impedance spectroscopy. They were analyzed using a classical 'brickwork' equivalent circuit composed of grain and grain boundary contributions commonly applied to solid-state materials. The obtained grain resistance/capacitance was 0.4 MΩ/72 pF and grain boundary resistance/ capacitance was 66.4 MΩ/50 nF. The determined conductivity changed according to the Jonscher power law with σDC of 4.02 · 10–5 (Ωm)−1 and frequency constant of 0.92 characteristic for hopping as the conduction mechanism. Analysis of dielectric permittivity and electric modulus confirmed the non-Debye relaxation behavior. Nyquist plots for electric modulus revealed conductivity relaxation in the low frequency attributed to grain boundaries and impedance modulus displayed dielectric relaxation in the high frequency region associated with grains. A correlation has been established among the investigated parameters, morphology, and EIS-derived simulated parameters