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Influence of the cultivar, fertiliser, and irrigation on iceberg lettuce morphology - single factor vs interaction effects
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
Novel batavia lettuce cultivars-choosing the optimal cultivar for fresh and processed products using WASPAS method
No full textSix Batavia lettuce cultivars ('Tourbillon', 'Champollion', 'Impression', 'Voltron', 'Bataille', and
'Batsun') were grown in the black marsh soil in March-May 2020. 'Tourbillon' is a standard
Batavia cultivar, while five others are not registered on the Variety list in Serbia. This study
aimed to select the optimal Batavia cultivar according to agronomic parameters, suitable for
the fresh market and processed products by applying the WASPAS (Weighted Aggregates
Sum Product Assessment) method. The correlation analysis was carried out to reduce the
number of criteria having high coefficient values above 0.8 to exclude double influence on the
ranking results. The study involved six alternatives (cultivars) and six different criteria
regarding agronomic parameters (rosette height, rosette fresh weight, number of leaves, stem
diameter, stem fresh weight, and core ratio). According to the expert’s opinion, we depicted
morphological traits of interest significant for fresh and processed lettuce products. Thus,
according to the selected criteria and both scenarios, the obtained results showed that cultivar
A2-'Voltron' was the best-ranked for fresh and processed products, while cultivar A3-
'Champollion' showed the least favorable results. A SAW (Simple Additive Weighting)
method was applied to verify and confirm the obtained results by the WASPAS method.
Therefore, this study showed that the WASPAS method could present an initial step toward
decision-making in the selection of novel lettuce cultivars for the fresh market and ready-to-
eat salads and highlighted the importance of choosing the adequate cultivar for different
purposes to avoid quality and economic losses
Effects of urban life on the gut microbiota and the susceptibility to avian malaria infection in a population of the house sparrow Passer domesticus
No full textLife in urban areas may alter the gut microbiota and host physiology, leading to a higher susceptibility to pathogens. In contrast, specific members of the gut microbiota community have been shown to mitigate the intensity of malaria infection. House sparrows, living in close proximity to humans, are exposed to a unique environment with human-shaped diets emerging as a particularly influential factor. In addition, sparrows host a significant number of avian haemosporidian and other blood parasites. We examined how the gut bacterial community of house sparrows varied across two close urban sites in the city of Belgrade and the potential impact of blood parasite infection on the gut microbiota. Our results show that diversity and composition of the gut microbiota were only influenced by the sampling location, likely due to variations in food resources, particularly the availability of bird feed at one of the sites (a zoo). In summary, our results suggest the local microbial adaptations to differing levels of urbanisation habitats, in this case most likely driven by artificial alterations in food resources, but not reaching to effects on the blood parasite fauna
FOTOSELEKTIVNE MREŽE KAO NOVI TEHNOLOŠKI PRISTUP ZA POBOLJŠANJE PROIZVODNIH PERFORMANSI I KVALITETA PLODA BOROVNICE GAJENE U SUPSTRATU
No full textRad predstavlja rezultate komparativnog ispitivanja uticaja različito obojenih fotoselektivnih protivgradnih mreža (plava, crvena i žuta mreža) i neutralnih fotoselektivnih mreža (biserna i crna mreža) na vegetativni rast, produktivnost i kvalitet ploda sorte borovnice ´Duke´ gajene u supstratu. Ispitivanja su izvedena u zasadu borovnice koji se nalazi u Gruži (opština Knić) tokom perioda 2022-2023. godina. Zasad je zasnovan u proleće 2017. godine sadnjom dvogodišnjih biljaka u saksije zapremine 113 l, koje su ispunjene mešavinom strugotine i belog treseta (50:50) i postavljene na rastojanje od 0,8 m u redu i 3,0 m između redova (4.170 biljaka/ha). Crvena fotoselektivna mreža je stimulativno uticala na vegetativni rast (visinu i širinu žbuna, i ukupan broj grana u žbunu) i doprinela je značajnom povećanju broja plodova i prinosa po žbunu (2642,2 i 5,8 kg/žbunu, po redosledu) u poređenju sa ostalim ispitivanim mrežama. Uticaj godine je bio značajan sa registrovanim povećanjem ukupnog broja grana u žbunu, širine žbuna, broja plodova i prinosa po žbunu u 2023. godini, dok su masa i dimenzije ploda, čvrstoća 1 i 2, kao i sadržaj rastvorljive suve materije bili značajno veći u 2022. godini. Prosečna masa ploda kretala se u rasponu od 2,01 g (crna mreža) do 2,47 g (crvena mreža). Biserna mreža je ispoljila pozitivan uticaj na čvrstoću 1 (16,18 g), dok kod čvrstoće 2, kohezivnosti i elastičnosti pokožice ploda nisu uočene značajne razlike između boja mreža. Plava mreža je pozitivno uticala na sadržaj rastvorljive suve materije u plodu (12,2%), kao i na značajno smanjenje sadržaja ukupnih kiselina (0,43%). Crvena mreža je doprinela većoj sintezi ukupnih fenola i ukupnih antocijanina u plodu (1,62 mg galne kis. ekv/g sv.m.pl. i 50,07 mg malvidin-3-glukozida ekv/100 g sv.m.pl., po redosledu), dok je kod crne mreže registrovano značajno smanjenje sadržaja fenolnih komponenti. Sličan trend se zapaža i u pogledu ukupnog antioksidativnog kapaciteta ploda, koji je značajno povećan pod uticajem crvene mreže (1,13 mg askorb. kis. ekv/g sv.m.pl.). Dobijeni rezultati ukazuju na značajan potencijal primene crvene fotoselektivne mreže u poboljšanju proizvodnih performansi i povećanju sadržaja fenolnih jedinjenja, kao i antioksidativne aktivnosti ploda borovnice gajene u supstratu
The far-field interplay between peripheral Cenerian Orogeny and inner north Gondwanan hinterland: Cambro-Ordovician siliciclastic veneer and pre-Hirnantian unconformities (Sahara, central Libya)
No full textIntra-Ordovician geodynamics along the northern Gondwana margin, defined in most parts of exotic southern peri-Gondwanan Europe, had a far-field effect on the subsiding Gondwanan interior. The outboard peripheral Cenerian Orogeny influenced the ongoing subsidence and deposition of monotonous clastic Cambrian – Lower Ordovician mega-sequence unconformably overlying North African basements. A combination of literature review and field mapping provides first-order constraints between the truncated Cambro-Ordovician successions of central Libya and peri-Gondwanan intra-Ordovician deformation recorded in south-European and Alpine-
Carpathian-Balkan basements (unconformity markers). The data synthesis further permits a genetic connection between the detached exotic Ordovician northeastern Gondwanan flank (south Europe/Alps-Carpathian-Balkans) and its subsiding Ordovician intra-cratonic hinterland. By coupling the complex stratigraphic, detrital zircon, and ironstone datasets as unconformity markers, link between south-central European and North African Ordovician imprints is provided.
Several Gondwanan intraplate truncations in stratigraphy coincide with recurrent Ordovician geodynamical interferences, particularly unconformities embedded into the northeastern Gondwanan assemblage. The most relevant of these intraplate truncations is the so-called "intra-Arenigian" angular unconformity. The “intra-Arenigian”
angular unconformity coincides with eastern Gondwanan Cenerian or Sardic intra-Ordovician deformational episodes. The “intra-Arenigian” angular unconformity separates monotoneous super-mature clastic Cambrian-Lower Ordovician from Darriwilian strata of North African hinterland, or the Hasawnah from the Hawaz Formations. The stratigraphic position of this angular unconformity fits with the outer-shelf active margin-related geodynamic compressional interferences (collision or “docking”, no crustal thickening involved).
Broadly analogous intra-Ordovician geodynamic relationship was already recognized in detached exotic south European Variscan terranes referred to as the Sardic and Sarrabese mid-Ordovician tectonic phases. The detrital zircon populations within the transgressive Middle Ordovician Hawaz Formation suggest a provenance change consistent with a vast shallow shelf linking the northeastern Gondwanan flank and hinterland. The post-unconformity sequence or stratigraphically lowermost Hawaz K-bentonites of the Darriwilian age and the recently mapped basalts interbedded within the Melaz Shuqr¯ane Formation (Upper Katian-Hirnantian) could be in correlation with a short-lived back-arc or rift-related (intracratonic) volcanism. The Ordovician back-arc extension or rifting event postdates the accretionary tectonics in the outboard flanking Cenerian Orogeny.
Such magmatism could be in relation to the Late Ordovician – Silurian rift and drift-off of the peri-Godwanan terrane assembly.Embargo je 24 mesec
EXPERIMENTAL EVALUATION OF THE THERMAL CONDUCTIVITY OF CORN LEAVES CEMENT BOARD
No full textDue to environmental and economic issues, there has been a growing interest in the potential use of agricultural waste as a raw material to make structural reinforcing fibers for construction materials in recent years. Corn is the world's most produced cereal in terms of quantity, which results in significant amounts of waste. However, only a few studies on the use of fibers from discarded corn in the production of fiber-cement have been reported. Due to a major lack of data on the aspects of this application, the purpose of this article was to investigate the feasibility of creating cement board with the inclusion of corn leaves. Corn leaves cement boards were made with the addition of treated corn leaves. SEM analysis of boards was provided in order to show the corn leaves-cement matrix surface morphology. The addition of corn leaves to the cement board reduces thermal conductivity, which minimizes heat transmission and energy consumption in structures. The low thermal conductivity of the construction material contributes to the energy efficiency of the building. The coefficient of heat conductivity was determined using HRN EN 12939:2000 and ISO 8301:1991. The samples used to calculate the thermal conductivity coefficient were 15x15x4 cm in size
Comparison of electrodeposited composite coatings composed of commercial and synthesized MoO2 embedded in Ni for hydrogen evolution reaction
No full textIt is commonly known that the need for clean source of energy with the production and manufacturing costs being at the level of current solutions is getting greater. Among other candidates hydrogen shows great potential as substitution for fossil fuels because of its high energy content and possibility to be produced with zero emissions if the right method is chosen. Water electrolysis represents an excellent candidate for that role, but to achieve high efficiency concentrated hydroxide solutions serve as electrolytes in those systems. An advantage of the alkaline media is the possibility to use non-precious metals as catalysts, such as nickel. Ni is fairly stable in alkaline media and as an abundant element it is commonly used in alkaline water electrolysis as a catalyst substrate, or electrode itself. Transition metal oxides show excellent activity for hydrogen evolution reaction (HER) and have synergetic effect with Ni [1], based on that and the previous experience of our research group [2] this work is focused on catalysts composed of composite Ni-MoO2 electrochemically deposited on different porous Ni substrates. Firstly, the objective was to produce coatings consisted of MoO2 with the smallest particles commercially available embedded in Ni. Ultrasound assisted electrodeposition showed no results due to the corrosive environment of the deposition bath, as well as the erosion effect of the particles (100nm) on the ultrasonic probe. Promising results were achieved when air bubbling toward the bottom of the cell was used as a method for keeping the non-metallic MoO2 particles suspended in the solution. Considering the cost of the catalyst in order to try to reduce the production cost (and enhance the activity for HER) the second part of the research focuses on coatings with synthesized MoO2, which has proven before to show better results [1]. Even though the electrodes coated with Ni-MoO2 containing MoO2 synthesized in our lab had less electrochemically active surface area (the substrate was Ni mesh that doesn`t offer as much surface area as Ni foam used as substrate in first part of research) it showed much better activity towards HER. Overpotential on current density of -500 mA cm-2 was -88 mV, being 30 mV lower than on Ni foam electrode coated with composite containing commercial MoO2 particles which can be seen od Figure 1. In the production of this type of catalyst, the method for dispersing MoO2 through the bulk of the solution was stirring with magnetic stirrer and circulating the electrolyte during the deposition. The future goal is to continue the work on finding the optimal conditions for preparing a coating with the same characteristics on Ni foam substrate which should have even higher activity towards HER
Early warning signals of genotoxic compounds in native and invasive fish: A case study from Sava Lake
No full textThe Sava Lake was formed in the late 1960s, when Sava River island was turned (artificially) into the peninsula in Belgrade, Serbia. It represents the most organized sports and tourist complex in Belgrade and an active water recreational area for citizens. Throughout the year, a large number of tourists visit the lake, and this increases pollution pressure. Additionally, the presence of the invasive fish black bullhead (Ameiurus melas) may disrupt water quality and lead to habitat degradation, potentially facilitating the successful establishment of viable populations of allochthonous, invasive species. However, ecogenotoxicological studies on this lake have never been conducted. Therefore, this research aims to detect "early warning signals" of organisms' exposure to genotoxic compounds, focusing on the native European perch (Perca fluviatilis) and the invasive species species - black bullhead, to determine which species is under greater greater pollution/contamination/anthropogenic pressure. The comet and micronucleus tests were applied, as DNA damage could be a useful biomarker for detecting "early warning signals" of exposure to genotoxic compounds. Individuals were examined during the summer and winter seasons. The comet assay revealed statistically significant differences in DNA damage between native and invasive individuals, with invasive individuals exhibiting significantly less DNA damage (P. fluviatilis with average TI%: 18.06; 23.23 and A. melas with TI% 5.47; 7.51 for July and December, respectively). Lower levels of DNA damage were detected during the summer season for both species. The number of nuclear abnormalities and micronuclei also differed between species, with a significantly higher number detected in the native species and for both species in the summer month. Based on the aforementioned findings, the selected tests proved to be effective for early detection of DNA damage and showed a good discriminatory potential for assessing the resistance of different species to genotoxic compounds, highlighting the resistance of the invasive species
IMPROVEMENT OF LOCAL PIEZOELECTRIC AND MECHANICAL PROPERTIES OF GLYCINECHITOSAN BIOPOLYMER COMPOSITE BY INCORPORATION OF Ti3C2TX MXene SHEETS
No full textABSTRACT: Piezoelectric biomaterials are unique class of semicrystalline
materials exhibiting electromechanical behavior by undergoing
electric polarization under mechanical loading even in the absence of an
external electric field. Since those materials are commonly biodegradable,
biocompatible and non-toxic, they are particularly attractive for use in
regenerative medicine and biomedical devices.
Chitosan (Ch), a natural, non-toxic, biodegradable, biocompatible material
with excellent antibacterial properties is one of the most studied piezoelectric
biomaterials. This linear polysaccharide derived from chitin is the second
most abundant polymer in nature. The most prominent problems of using only
Ch as a piezoelectric biopolymer applications arise from its poor macro- and
micro-scale piezoelectric response and poor mechanical properties. Those
issues can be mitigated by processing a composite with superior properties by
combining biocompatibility and biodegradability of Ch, with good
mechanical, and/or good piezoelectric properties of biocompatible materials,
like nanofibrillar cellulose and collagen, respectively. Recently, it was also
shown that biodegradable amino acids, e.g. glycine (Gly), can be selfassembled
in organized polar crystalline structure within Ch, making a composite suitable for pressure sensors. With the same purpose, nano-fillers
such as hydroxyapatite, carbon nanotubes, graphene, and metal oxide
nanoparticles were being explored as fillers for chitosan. In addition to the
widely studied carbon nanotubes and graphene, MXene sheets, the electrically
conductive and hydrophilic 2D materials could be promising candidates for
high-performance Ch-based pressure sensors.
Herein, we investigated the local piezoelectric and mechanical properties of
chitosan-glycine (Ch-Gly) biocomposite with Ti3C2Tx, MXene sheets. MXene
was expected to reinforce the Ch-Gly composite and increase the piezoelectric
d33 coefficient. Varying Gly to Ch weight ratio, the growth of single-phase,
piezoelectric β-glycine in Ch matrix was achieved only at composition
Ch:Gly=1:0.8 wt%. For the processing of Ch-Gly and Ch-Gly-MXene films,
spin-coating technique followed by drying at room temperature was
employed. MXene sheets were synthesized by “minimally intensive layer
delamination” (MILD) of Ti3AlC2 MAX phase using LiF with 9M HCl as
etchant. The concentration of aqueous dispersion for the thin film processing
was regulated to 0.23 mg/ml, and added to Ch-Gly solution to achieve
Ch:Gly:MXene=1:0.8:3.2·10-4 wt% ratio. This composition was adopted to
minimize toxicity concerns as much as possible, thus the final Ch-Gly-MXene
solution contained only 5 μg/ml of MXene. The morphology and
microstructure of the films were studied using optical imaging and atomic
force microscopy (AFM), while the XRD analysis was used to identify the
films’ phase composition. Local mechanical and piezoelectric analyses were
performed on AFM by AM-FM viscoelastic mapping, PFM DARTSS and
PFM lateral DARTSS measurements. It was confirmed that small amount of
MXene can improve the piezoelectric properties and significantly reinforce
Ch-Gly films since the average value of the Young’s modulus increased
twofold
Mn content as a marker of transgressive events: an example of some Balkan bauxites, Babušnica site
No full textOur novel research on Mn content as markers of transgressive events/eustatic changes in marine carbonate environments not only provides a fresh perspective on the development of the Tethyan Ocean and its branches, “Alpine Tethys”, as a key area of study in our field, but also offers practical applications. Namely, Mn deposits, often formed in deep to middle-depth marine environments associated with regional extension, are vital in numerous Mesozoic Tethys-related oceans spreading across the Balkans. The Mn role is vital, especially in indicating hitherto undocumented principal stages of eustatic changes essential for following ancient paleooceanic developments. This research significantly deepens our understanding of the Tethys Ocean s.l., particularly the underexplored southern realm of Alpine Tethys (southeastern Serbia). It contributes to the broader paleoceanography and tectonics, with potential implications for future studies and applications in field mapping