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THE LATER, THE BETTER? DIFFERENCES IN FIELD PERFORMANCE AND FRUIT QUALITY TRAITS IN NEWLY INTRODUCED ITALIAN SHORT-DAY STRAWBERRY CULTIVARS
Get PDFThe aim of this study was to compare newly introduced mid- and late-ripening strawberry
cultivars ('Arianna', 'Tea' and 'Federica') with the commercially important cultivar 'Joly' to identify
the best-performing ones for extended market supply. A field study was carried out in a
strawberry plantation situated in the municipality of Šid (Serbia), in the period of 2021–2022. The
orchard was planted in July 2020 in double rows on beds covered with black polyethylene foil.
Cultivars were evaluated for their flowering and ripening time, yield components, and plant
growth, as well as for biometrical fruit traits (fruit weight, index of fruit shape) and nutritional
value (the content of soluble solids - SSC, total acids - TA, vitamin C, total anthocyanins –TACY,
total phenolics - TPC and total antioxidant capacity - TAC). This research revealed that the earliest
average beginning of ripeness was recorded in cultivar 'Arianna' (May 19), while the latest was in
cultivar 'Federica' (May 29). The number of branch crowns and leaves per plant was significantly
lower in cultivars 'Tea' and 'Federica' compared to the cultivar 'Joly', whereas no significant
differences in plant height were observed among the tested cultivars. 'Tea' was superior in terms
of highest productivity (947 g/plant and 4.17 kg/m2
), followed by the cultivar ‘Joly’ (865 g/plant
and 3.81 kg/m2). Contrary to this, the lower yield was found in the two other tested cultivars
'Federica' (698 g/plant and 3.07 kg/m2) and 'Arianna' (773 g/plant and 3.40 kg/m2). The most
productive cultivar 'Tea' had the largest fruit weight (29.7 g) and it was also characterized by the
lowest content of TA, TACY, and TPC (0.56%, 18.5 mg PG-3-G eq 100 g-1 FW and 0.72 mg GA eq/g FW, respectively). Significantly higher amounts of soluble solids were found in all newly
introduced cultivars in comparison to the standard cultivar 'Joly' (9.15%). The differences in TAC
levels between 2021 and 2022 were significant showing higher values in the second year of trial with the dominance of cultivar 'Arianna' (1.24 mg AsA eq g-1 FW)
Past and Future of Sturgeon Species (Acipenseridae) in Western Balkans: Case for Permanent Conservation or Sustainable Management
Get PDFSturgeon species in Western Balkans are mainly occupying the Danube River basin, which represents one of the centers for sturgeon diversity. Although there are numerous negative anthropogenic impacts (habitat fragmentation, pollu- tion, fishery pressure) on sturgeons, constructions of hydropower dams in the Iron Gate area severely decreased their natural spawning habitats and only sterlets have a viable population upstream from Iron Gate 2 dam. Review of the status and population trends based on available statistics, pollution impact, composition and change in their diet, the impact of invasive species, as well as restocking and ex situ conservation programs will be presented. Assessment of legislation and sturgeon protection projects and their impact on wild sturgeon populations will be discussed
WILD GROWING GEOPHYTES IN THE NORTHERN KOSOVO AND METOHIJA – POTENTIAL OF ORNAMENTAL USE
Get PDFThe region of Northern Kosovo and Metohija
is rich in wild-growing geophytes, many of which
have potential for ornamental use. However, the
knowledge about the distribution, abundance, and
potential of these species for the horticultural indus try is limited. This study is based on our own re search conducted continuously in the region of the
northern Kosovo and Metohija, from 2003 to 2023,
as well as on a small number of relevant literature
sources and floristic data. This study aimed to eval uate the ornamental potential of wild-growing geo phytes in the investigated area and to provide rec ommendations for their sustainable exploitation.
The study recommends the protection of species
covered by CITES convention and IUCN Red List
of Threatened species. Using wild-growing geo phytes as ornamental plants can contribute to the
conservation of biodiversity in the region while
providing economic benefits through their commer cial cultivation
Single-Molecule Probing By Rectification in a Nanogap
Get PDFHere in this talk, we propose the simultaneous measurement of rectification and amplitude of tunneling current during electrical probing of a molecule in a nanogap for efficient single-molecule detection. Also, we suggest the application of nitrogen-terminated graphene or CNT nanogaps due to their inherent outstanding features. With DFT and Non-Equilibrium Green's Function formalism, we show that tunneling current through various molecules, including ssDNA, TATP, or small organics placed in those nanogaps, exhibits unique rectification behavior under square pulses of alternating bias. The rectification arises by on-off switching of electronic transport through the molecular HOMO or LUMO levels, sustained by partial charging of the probed molecule, generated by asymmetric hybridization of that level with Bloch states from one of the electrodes. An effect that mimics local gating, i. e. an interaction between the molecule and the nitrogen-induced dipole moment located at the N-C interface of the electrode ends, strongly influences the rectification. The simultaneous measurement of rectification and amplitude of tunneling current could be applied to gas-phase single-molecule detection, as shown in the example case of the TATP. The TATP (triacetone triperoxide) is a volatile, potent, and hard-to-detect explosive made from commonly available chemicals, a terrorist weapon of choice in the last two decades. The rectification could also be applied in the liquid phase, offering the possibility of high-throughput and precise DNA sequencing. We found that the environment (neighboring nucleotides, water molecules, and counterions) does not mask ssDNA rectification while ssDNA traverses the nanogap
Case study of mountainous geothermal reservoirs (Kopaonik Mt., southwestern Serbia): Fault-controlled fluid compartmentalization within a late Paleogene-Neogene core-complex
No full textA composite hydrogeothermal survey of the magmatic-metamorphic post-NeoTethyan Neogene crustal core-complex of the Kopaonik Mt., southwestern Serbian highlands, provides new constraints on the subsurface hydraulic across- and along-fault flow fluid regimes and geothermal anomalies associated with the two shallow reservoirs. The study is involving synergistic approach by combining structural geology, exploratory drilling, temperature logging, hydrochemical and hydrodynamic constraints further illustrating a complex conduit–barrier fault-controlled spatial compartmentalization of the two thermal water reservoir(s). The thermal waters of the Kopaonik Mt. geothermal field are channeled by the major regional faults and associated fracture zones that are crosscutting the volcanics and the adjoining metamorphites. The results show that the subsurface compartmentalization of the active reservoirs, which are supplying the spa town of Jošanička banja, are controlled by a seismically active regional faults (including the fault that is crosscutting the Slanište locality, having N-S trending). Owing to the linear channeling of the fault-controlled reservoirs, in which the main quantitative water circulation takes place, it was possible to identify the thermal fluid flow paths and associated recharge zones (catchments). The Jošanička banja thermal waters reservoir is accommodated at ca. 400-500 m depth, whereas the Slanište aquifer maintains a shallower position. The new surface - subsurface constraints allowed the estimation of the subsurface reservoir elevations, pinpointing the origin of shallow crustal geothermal processes. Of particular importance is better understanding of the subsurface spatial distribution and the ultimate depth of the developing Kopaonik Mt. geothermal field. The new interpretation shows a qualitative agreement with the core-complex-related heat sourcing, as well as the fault-controlled reservoir compartments, impacting the efficient extraction of the thermal waters, in terms of quantity, quality and water temperature
PROPERTIES OF MULTIFERROIC YMnO3 SYNTHESIZED BY DIFFERENT METHODS
No full textMultiferroics are functional materials in which two or more primary ferroic properties (ferroelectricity, ferromagnetism or ferroelasticity) coexist in the same phase. These interesting properties offer possibilities for many different technological applications of multiferroics including non-volatile ferroelectric memories, sensors, transducers, microwave devices, among others. For these reasons, multiferroic materials are widely investigated but the preparation of single-phase multiferroic materials is itself a very challenging task, involving innovative chemistry and/or combined synthesis methods.
Rare earth manganites (REMnO3) are one of the most studied groups of multiferroic materials. They exhibit simultaneously ferroelectric and ferromagnetic properties, and depending on the RE cation radius, can crystallize in either hexagonal or orthorhombic system. Among this group of materials, yttrium manganite (YMnO3, YMO) stands out since it crystallizes in both these structures: the hexagonal (h-YMO) structure, stable under atmospheric conditions, and orthorhombic structure (o-YMO), the metastable one.
Various synthetic procedures are applicable for the synthesis of YMO powders, but some challenges concerning the preparation of the single phase YMnO3 bulk ceramic materials still remain. Possible change of the manganese oxidation state during the synthesis affects the phase composition, and in particular magnetic properties of YMO ceramics since the existence of two or more different oxidation states of Mn violates the antiferromagnetic order in the prepared material. Additionally, during sintering process a high temperature phase transition from paraelectric to ferroelectric phase in h-YMO occurs, resulting in large volume change which together with highly anisotropic thermal expansion coefficients generates the microcracks in the sintered samples. This phenomenon influences the ferroelectric properties of the sintered samples.
From this perspective, we investigated the impact of different synthetic paths on the properties of the YMnO3, both powders and ceramic materials. Precursor YMO powders were obtained via mechanochemical and chemical synthesis and sintered by conventional and Spark Plasma Sintering techniques.
In this contribution we will give an overview of our results and compare YMO ceramic materials prepared by means of two different methods
KIT-5-Assisted Synthesis of Mesoporous SnO2 for High-Performance Humidity Sensors with a Swift Response/Recovery Speed
Get PDFDeveloping highly efficient semiconductor metal oxide (SMOX) sensors capable of accurate and fast responses to environmental humidity is still a challenging task. In addition to a not so pronounced sensitivity to relative humidity change, most of the SMOXs cannot meet the criteria of real-time humidity sensing due to their long response/recovery time. The way to tackle this problem is to control adsorption/desorption processes, i.e., water-vapor molecular dynamics, over the sensor’s active layer through the powder and pore morphology design. With this in mind, a KIT-5-mediated synthesis was used to achieve mesoporous tin (IV) oxide replica (SnO2-R) with controlled pore size and ordering through template inversion and compared with a sol-gel synthesized powder (SnO2-SG). Unlike SnO2-SG, SnO2-R possessed a high specific surface area and quite an open pore structure, similar to the KIT-5, as observed by TEM, BET and SWAXS analyses. According to TEM, SnO2-R consisted of fine-grained globular particles and some percent of exaggerated, grown twinned crystals. The distinctive morphology of the SnO2-R-based sensor, with its specific pore structure and an increased number of oxygen-related defects associated with the powder preparation process and detected at the sensor surface by XPS analysis, contributed to excellent humidity sensing performances at room temperature, comprised of a low hysteresis error (3.7%), sensitivity of 406.8 kΩ/RH% and swift response/recovery speed (4 s/6 s)
Use of biochemical methods for assessing oxidative stress in trees in urban area during growing season
Get PDFDue to increased urbanization and industrialization, the emission of toxic material into the
atmosphere is in expansion, which has a negative impact on the environment and human health. In
this research, we monitored the effect of air pollution on the peroxidase (POD) activity and total
antioxidant capacity of different tree species during the growing season. The main goal was to
determine which tree species developed the highest tolerance to unfavorable environmental
conditions at the end of growing season, based on the response of their antioxidative metabolism. The
greatest change in POD activity was observed in the Fagus sylvatica L. leaves, where enzyme activity
was more than doubled in the autumn, in comparison to spring. On the other hand, decrease in POD
activity was the greatest in Cedrus atlantica (Endl.) Manetti ex Carrière needles. Moreover, total
antioxidative capacity was altered during growing season in almost all examined tree species. The
Magnolia spp. showed the most consistent response to the given environmental pollution with both
portrayed parameters induced during growing season. In general, we can conclude that the tree
species investigated in this research possess distinctive tolerance potential to air pollutants
Comparison of two recent approaches to DTB characterization of ferritic steels
Get PDFThe large scatter of the experimental fracture toughness data, characteristic of all ferritic steels in the ductile-to-brittle transition
temperature region, imposed the need to include statistical methods for data processing. Due to the inherent stochasticity, the
application of fracture mechanics concepts in the characterization of the DTB transition phenomenon has remained a challenging
task over the past 50 years. Various models were developed based on statistical approach to data processing in order to capture
the salient features of the phenomenon, but all of them have certain limitations because of the intrinsic complexity of the
problem. However, all these models provided a solid basis for the continued development of new approaches in the
characterization of DTB. Such two novel models are compared herein. They include size effects and utilize scaling of
geometrically similar C(T) specimens, with the aim of obtaining predictions of the fracture toughness. Both proposed models
have the weakest link statistics in common. In the present study, the EURO fracture toughness data set for 22NiMoCr37 reactor
steel is used and the experimental data obtained at temperature of -60 ºC is selected to demonstrate the accuracy of the estimates.
The fracture toughness measure used is the critical value of the stress intensity factor used in the master curve KJc [MPa√m].
The obtained predictions are in good agreement with the experimental results, taking into account the inherent scatter of the
experimental data. The estimate of KJc cumulative distribution function obtained by extrapolation using the novel two-stepscaling
method is sensitive to the statistical size of the input data sets
Growth elements and stand structure of artifically established Norway spruce stand at 37 and 62 years of age on Dalechamps Oak Site at Goč
Get PDFNa jednoj trajnoj oglednoj površini u veštački podignutoj sastojini smrče na staništu balkanskog kitnjaka na Goču prikazani su elementi rasta i sastojinska struktura u starosti 37 i 62 godine i analizirana je njihova promena. Sastojina je podignuta sa 4500 sadnica po hektaru. U starosti 37 godina na trajnoj oglednoj površini utvrđeno je 2600 stabala po hektaru, sa temeljnicom 43,52 m2·ha−1 i zapreminom 319,97 m3·ha−1, a u starosti 62 godine utvrđeno je 878 stabala po hektaru sa temeljnicom 42,61 m2·ha−1 i zapreminom 454,48 m3·ha−1. Prva selektivna proreda, sprovedene pri srednjoj visini aspiranata (500 po hektaru) 17,6 m u starosti 37 godina je bila niska (qd = 0,88) i umerene jačine po broju stabala (28,3%) i zapremini (23,5%). Od preostalog broja stabala (1823 po hektaru) u periodu od 38. do 62. godine iz sastojine je pretežno sanitarnom sečom izlučeno 956 stabala (52,4%), sa pokazateljem niske prorede (qd = 0,68). Od početno izdvojenih aspiranata u 37. godini do 62. godine, pod uticajem biološkog diferenciranja stabala i pod uticajem nepovoljnih egzogenih faktora, a u postupku nege koji karakteriše niska proreda, u sastojini je izdvojeno 220 stabala budućnosti po hektaru. U 62. godini u sastojini su prisutni elementi nepovoljne izgrađenosti i statičke nestabilnosti jer je stepen vitkosti povećan u odnosu na stanje u 37. godini, pa se može zaključiti da je povećan i rizik za ostvarivanje njene potencijalne proizvodne i meliorativne uloge, a što je primarno posledica izostanka adekvatne nege u periodu od 38. do 62. godine.Growth elements and stand structure of an artificially established Norway spruce stand were presented at age 37 and 62-yr on the basis of a single permanent sample plot and their changes analyzed. The stand was established with 4500 seedlings per hectare. At age 37-yr on the permanent sample plot, 2600 trees per hectare were recorded with basal area of 43.52 m2•ha−1 and standing volume of 319,97 m3•ha−1. At stand age 62-yr, 878 trees per hectare were recorded with basal area of 42.61 m2•ha−1 and standing volume of 454,48 m3•ha−1. First selective thinning, conducted at mean aspirant’s height of 17.6 m (500 trees per hectare) at age 37-yr was characterized as a moderate (28.3% trees per hectare and 23.5% volume thinned) thinning from below (qd = 0.88). Out of the remaining number of trees (1823 per hectare), in the following period between 38-62-yr, 956 trees per hectare (52.4%) were removed, mostly through sanitary cutting that can be characterized as thinning from below (qd = 0.68). Out of the initially selected aspirants at age 37-yr, 220 elite trees were selected at age 62-yr due to the effects of self-thinning in the stand and unfavorable exogenous factors as well as the thinning from below regime. At age 62-yr, the stand structure is unfavorable and statically unstable as the slenderness coefficient is increased compared to the condition at 37-yr. Thus, it can be concluded that the risk for achieving the productive and meliorative potentials of the stand is increased, primarily due to absence of adequate maintenance of the stand between age 38 and 62-yr