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Elusive Permian – Triassic Western Paleotethyan paleogeography: Towards the Early Cimmerian pre-Vardar configuration (Dinarides-Carpathian Balkan Belt)
No full textThe Dinarides and Carpathian-Balkans, the western Balkan Peninsula, form an essential link between the Paleotethyan branches of the Adriatic Sea (Montenegro, Croatia) and that related to a multistrand Paleo- and Neotethys Vardar oceanic margin (Serbia). These post-Variscan paleo-margins have not been profoundly correlated with the neglected imprints of Paleotethyan closure, early Alpine extension, and subsequent lagged Upper Triassic Cimmerian orogeny until now. The Permian–Triassic western Paleotethyan imprints are documented near Moesia (Carpathian-Balkans, Rhodopes, Strandja, and North Dobrogea), including Hellenides and Pontides, where the Cimmerian structures are most prominent. Prior to the onset of the Upper Triassic compression and the predating closure of Paleotethys, the two segments of north Gondwana, ‘Greater Adria’ (or Apulia/Adria/Dinarides) and Carpathian-Balkan north Gondwanan-type basements (Serbo-Macedonian/Supragetic/Getic including Danubian), experienced the latest Devonian - early Carboniferous or “early Variscan” ophiolite-decorated suturing (ophiolites are in the case of Carpathian-Balkan suture). This initial stage of the Variscan collision was followed by the recurrent early Permian “late Variscan” accretionary-type amalgamation (granites and repeatedly intruded syenites; Getic basement). The effects of the asymmetrically continuing subduction on the polydeformed configuration of Dinarides and Carpathian-Balkans show, however, no explicit evidence that the Paleotethyan subduction was terminated by continental collision so that mixed Variscan-Cimmerian terranes continued to face an open ocean. Neither Cimmerian-type mélanges nor Permian-Triassic blueschists-to-eclogites are documented northwest of Aegean External Hellenides.
Despite a number of difficulties, the synthesis of stratigraphic, paleogeographic, geophysical, and scarce detrital zircon data yields a new configuration outlining the two branches of post-Variscan Paleotethys that coexisted across the Balkan Peninsula. The “southern or Dinarides suture branch” of western Paleotethys is outside the External Dinaride carbonate platform (beneath the Adriatic Sea). The second yet segmented “Alps-Carpathian-Balkan Paleotethyan northern branch” connected the Alps with the Serbo-Macedonian hinterland (reflected by the geometry of the Jurassic-Cretaceous successor Vardar Zone). By contrast, the central Serbo-Macedonian margin (“northern segment” of ”Carpathian-Balkan Paleotethyan branch”) exhibits no evidence of intensive post-Variscan magmatism relative to the “southern Serbo-Macedonian/Rhodopes/Aegean” branch. While the subduction beneath the “northern Serbo-Macedonian segment” lacks evidence of tectonothermal activity between the Permian-Late Triassic, its “southern limb” (Rhodopes/Pelagonian massif/Inner Hellenides) overrode still active Permian-Triassic subduction/magmatic arc. However, the synthesis further shows that the Permian – Triassic tectonomagmatic developments, particularly the tectonothermal imprints embedded across the southern Serbo-Macedonian limb, are inherently mixed. The geochemical data show a combination of margin-related rifting and subduction-related geochemical signatures. These marginal developments yielded several early Alpine continental rift basins followed by the formation of Triassic ophiolites, whereby the hinterland interior developed N-S-directed carbonate platform-type basins. The successor closure of the northward-directed Permian – Late Triassic Paleotethys was by the collision of the Cimmerian segment/magmatic arc along the periphery of Eurasia(Moesia). The Cimmerian collision depicted by the ultra-high-pressure metamorphic event in Rhodopes produced the late Triassic deformation spreading across the Carpathian-Balkan-Rhodopes-Strandja interior. This Late Triassic Paleotethyan closure and Triassic “Early Cimmerian Orogeny” affected the early Alpine incipient rift basins (Volvi-Therma in western Rhodopes/southern Serbo-Macedonian). “Early Cimmerian Orogeny” additionally interrupted the development of the interior carbonate platform (Getic; eastern Serbia)
SARS-CoV-2 PLpro Inhibition: Evaluating in Silico Repurposed Fidaxomicin’s Antiviral Activity Through In Vitro Assessment
No full textThe emergence of drug-resistant viruses and novel strains
necessitates the rapid development of novel antiviral therapies.
This need was particularly demanding during the COVID-19
pandemic. While de novo drug development is a timeconsuming
process, repurposing existing approved medications
offers a more expedient approach. In our prior in silico
screening of the DrugBank database, fidaxomicin emerged as a
potential SARS-CoV-2 papain-like protease inhibitor. This study
extends those findings by investigating fidaxomicin‘s antiviral
properties in vitro. Our results support further exploration of
fidaxomicin as a therapeutic candidate against SARS-CoV-2,
given its promising in vitro antiviral activity and favorable safety
profile
Assembling of truncated deterministic aperiodic lattices with defects using Weber beams
No full textWe introduce an experimental approach to realize truncated 2D deterministic aperiodic photonic structures using the interference of two mutually coherent Weber beams. The optical induction process for generating refractive index modulations in SBN crystal is controlled via various combinations of parabolic beams, with different offsets in both transverse dimensions, orientations, and relative phases, to obtain meta-structures
Ni-MoO2 Composite Coatings Electrodeposited at Porous Ni Substrate as Efficient Alkaline Water Splitting Cathodes
No full textTo obtain highly efficient yet easily produced water-splitting cathodes, Ni-MoO2 composite coatings were electrodeposited at a Ni foam substrate with an open-pore structure, pore size of 450 µm, in a Watts-type bath. The concentration of MoO2 particles (about 100 nm) was varied, while the intensive mixing of the solution was provided by air bubbling with 0.5 L min−1. Electrodeposition was performed at different constant current densities at room temperature. The morphology and composition of the coatings were investigated by SEM and EDS. The hydrogen evolution reaction (HER) was tested in KOH of different concentrations, at several temperatures, in a three-electrode H-cell by recording polarization curves and EIS measurements. The lowest achieved HER overpotential was −158 mV at −0.5 A cm−2. Up-scaled samples, 3 × 3.3 cm2, were tested in a single zero-gap cell showing decreasing cell voltage (from 2.18 V to 2.11 V) at 0.5 A cm−2 over 5 h in 30% KOH at 70 °C with electrolyte flow rate of 58 mL min−1. Compared to pure Ni foams used as both cathode and anode under the same conditions, the cell voltage is decreased by 200 mV, showing improved electrode performance
Two-Step-Scaling Approach to Size Effect Modeling of Fracture Toughness in DBT Region
No full textThis abstract outlines a strategy designed to offer estimates of fracture toughness using the Weibull cumulative distribution function (CDF) within the ductile to brittle transition (DBT) region. The size-effect modeling encompasses the dynamic interplay between brittle and ductile damage/fracture micromechanisms, which coexist in varying proportions within the DBT region depending on temperature. The inherent variability is tackled by employing a 3P-Weibull CDF. Application of the two-step-scaling (2SS) rest upon two scaling conditions along the CDF abscissa and ordinate (governed by the scaling parameters κ and ξ, respectively). The two scaling premises define in the scaled space the size-independent Weibull scale parameter (η⁎) and the common CDF slope S⁎ (i.e., the common PDF (probability density function) maxima), respectively. These two constancy conditions stem from the power law, intricately connected to Weibull statistics. This physically plausible power-law scaling is influenced by the traditional concept that the stress at the crack tip increases proportionally to the crack length raised to a power, establishing a connection between weakest link theory (WLT) and the Weibull statistics. When employing the 2SS scheme, the Weibull CDF adopts a modified WLT form. Finally, temperature-influenced DBT displays resemblances to behavior controlled by strain rates, particularly in scenarios of extreme loading causing shock waves that trigger nearly simultaneous activation of dominant nucleation kernels—an occurrence also witnessed at cryogenic temperatures
Ralstonia solanacearum - Genetic diversity determined by rep-PCR
No full textRalstonia solanacearum, the causative agent of bacterial wilt disease and brown rot of potato tubers, is a major threat to potato production worldwide and is designated a quarantine organism. Over the past fifteen years, this bacterium has occasionally appeared in potato crops in Serbia. Based on the research involving sequencing of multiple housekeeping genes (adk, gapA, gdhA, gyrB, ppsA, hrpB, and fliC), R. solanacearum strains originating from Serbia were characterized as genetically homogeneous and identical to strains present throughout Europe.
This work aimed to determine the existence of intraspecies genetic diversity among R. solanacearum strains obtained from potatoes in Serbia using a repetitive element palindromic PCR (rep-PCR).
A total of 73 strains of R. solanacearum, isolated from potatoes in various locations in Serbia, predominantly in Vojvodina during a six-year period (2013-2018), as well as R. solanacearum PD2762 reference strain, were included in the study. DNA of the R. solanacearum strains was isolated using the hexadecyltrimethylammonium bromide protocol (CTAB). The DNA was amplified using Polymerase Chain Reaction with primers BOXA1R, ERIC1R/ERIC2, and REP1R-I/REP2-I for BOX-PCR (BOX-A1R-based repetitive extragenic palindromic), ERIC-PCR (enterobacterial repetitive intergenic consensus), and REP-PCR (repetitive extragenic palindromic), respectively. The obtained amplicons were visualized by electrophoresis on 1% agarose gel stained with Midori Green Advance. The PyElph 1.4 software was used to analyze obtained DNA banding patterns of the tested and reference R. solanacearum strains and to construct the unweighted pair group method with an arithmetic mean (UPGMA) phylogenetic trees, illustrating similarity among R. solanacearum strains.
UPGMA phylogenetic trees based on ERIC-PCR patterns, distinguished three groups (Group IE – IIIE). Most strains were placed into Group IIIE (67 strains), five into Group IIE, while only one strain was clustered in Group IE with the reference R. solanacearum strain PD2762. According to the results of REP-PCR, strains were distinguished into five groups (Group IR – VR), with most of the strains being placed into Group VR (62 strains). Groups IR and IIIR consisted of two strains, Group IVR of one strain, while the remaining six strains and reference strain were clustered into Group IIR. DNA fingerprinting patterns obtained using BOX-PCR were identical for 73 tested R. solanacearum strains, as well as reference strain PD2762, indicating their homogeneity.
Given the inconsistency in the obtained results of multilocus sequence analysis (MLSA) and rep-PCR, whole genome sequencing should be incorporated in future work in order to get more informative results regarding the genetic diversity of R. solanacearum population(s) present in Serbia
Influence of the cultivar, fertiliser, and irrigation on iceberg lettuce morphology - single factor vs interaction effects-Abstract
No full textThis study aimed to examine the effect of cultivar, fertiliser and irrigation, and their combined
effect, on different lettuce agronomic parameters and the possible occurrence of tipburn. Two
iceberg lettuce cultivars ('Umbrinas' and 'Kavir') were cultivated during summer in the open
field, in the black marsh soil containing a wide calcium-to-magnesium ratio. Plants were grown
at a density 32×32 cm with regular agricultural practices. Three different levels of magnesium
sulfate fertiliser (100 ml, 300 ml, 500 ml solution) were added twice during the growing cycle.
Plants were irrigated using a drip irrigation system and sprinklers. After harvest morphological
parameters were estimated (head weight, height, diameter, number of leaves, fresh leaf weight,
stem height, diameter, and fresh weight). Cultivar 'Umbrinas' showed the highest value of all
parameters: head weight (557.15 g), head height (13.91 cm), head diameter (16.90 cm), number
of leaves (18.73), fresh leaf weight (527.50 g), stem height (65.73 mm), stem diameter (20.32
mm), and stem fresh weight (29.65 g). Application of all levels of magnesium sulfate fertiliser
did not affect observed parameters compared to the control. Drip irrigation led to significantly
higher head height, diameter and number of leaves, while sprinkler irrigation significantly
enhanced the values of all stem parameters. Tipburn was noticed mainly in the 'Umbrinas'
cultivar in the sprinkler irrigation treatment, whereas drip-irrigated plants showed no signs of
tipburn. Interaction of all three factors showed a statistically significant impact on head weight,
number of leaves, fresh leaf weight, and stem height
UV/Vis determining tartrazine (E 102) in a commercial food dye
No full textOur research presents an analytical curve applicable to accurately determining
unknown concentrations of tartrazine in an aqueous solution of any sample. The
analytical curve that this study develops may be used to determine the
concentration of tartrazine in an aqueous solution of a typical commercially
available food dye, which is a mixture of tartrazine and dextrose. The
concentration determined in the sample of the food dye was c=7.76 g/ dm3. The
examined food dye contained 0.27% of tartrazine. To characterize the presented
analytical method, LOD (limit of detection) and LOQ (limit of quantification)
were then calculated, obtaining better values compared to the data existent in the
literature
The Importance of Stand Structure in Narrow-Leaved Ash (Fraxinus angustifolia Vahl) Dieback—Insights from an Extensively Managed Stand on a Humogley Soil in Serbia
No full textAsh dieback is a major issue affecting European ash populations, including narrow-leaved ash (Fraxinus angustifolia Vahl). An important factor contributing to the decline of narrow-leaved ash is the fungal disease caused by Hymenoscyphus fraxineus. However, the mortality of trees also depends on stand structure that may influence the disease dynamics. In 2020, we analysed the stand structure of middle-aged, extensively managed, narrow-leaved ash stands growing on Humogley soil (Cariceto remotae-Fraxinetum angustifoliae, Jov., et Tom. 1979). This permanent sample plot is located in Posavina (Serbia), where we observed reduced tree vitality and mortality. The stand originates from natural regeneration after a succession of marsh habitats. At ages 20–25 years (1996) and 30–35 years (2006), selective thinning was carried out. Until the age of 45–50 years (2020), the stand was left unthinned, and the presence of ash dieback fungus was recorded in Serbia. In 2020, we measured the diameter at breast height (DBH) of each tree on the plot and assessed their crown class and degree of isolation. These parameters were evaluated in relation to the crown defoliation of the trees. The results indicate that reduced vitality and mortality of trees manifest in conditions of strongly expressed intraspecific competition in the stand, particularly during the stem exclusion stage. Healthy trees were observed primarily within the predominant/dominant crown class and exhibited the highest mean DBH. Trees classified as dead or dying (81%–100% defoliation) had a lower mean DBH compared to both healthy trees (<25% defoliation) and significantly defoliated trees (26%–80%). This was observed at both the stand level and in predominant/dominant trees, suggesting that tree mortality is primarily linked to their poor growth
THE IMPACT OF FERROUS AND FERRIC IONS ON DEGRADATION OF ANTIHYPERTENSIVE DRUG DIHYDRALAZINE IN IRON-BASED FLOCCULATION AND COAGULATION METHODS FOR WASTE WATER TREATMENT
No full textDihydralazine (dHZ) and hydralazine are hydrazine derivatives used as drugs in the treatment of
hypertension. These drugs and their metabolites can be long-term pollutants in domestic and
pharmaceutical industry waste water due to their high water solubility, low price and frequent use in
the treatment of chronic disease. There are many methods for waste water treatment and some of
them, such as flocculation, coagulation and advanced oxidation processes, involve the use of iron
salts. In this study we investigated the effect of pH on dHZ degradation in the presence of ferrous and
ferric ions in aqueous solutions using UV-Vis spectroscopy. It was found that in acidic solution dHZ
forms stable complex with ferrous ions. The presence of ferric ions in acidic and neutral aqueous
solutions of dHZ led to its degradation, which is faster at lower pH. EPR spectroscopy measurements
showed that degradation of dHZ induced by ferric ions proceeds with the formation of OH • and
carbon centered dHZ radical