158 research outputs found
Genetic algorithms and smoothing filters in solving the geophysical inversion problem
The combination of genetic algorithms, smoothing filters and geophysical tomography is used in solving the geophysical inversion problem. This hybrid technique is developed to improve the results obtained by using genetic algorithm sonly. The application of smoothing filters can improve the performance of GA implementation for solving the geophysical inversion problem. Some test-examples and the obtained comparative results are presented
Phylogeographic status and genetic structure of brown trout populations (Salmo cf. trutta) in Đerdap and Timočka krajina regions
Kontrolna regija mitohondrijske DNK pokazala se kao odličan filogeografski marker kad je kompleks potočne pastrmke (Salmo cf. trutta) u pitanju. Krajem 20. veka ustanovljeno je pet osnovnih filogeografskih linija (haplogrupa) potočne pastrmke: dunavska, atlanska, mediteranska, jadranska i marmoratus koje uglavnom korespondiraju sa odgovarajućim slivovima. Analizirane jedinke na području Srbije nosile su haplotipove dunavske, atlanske i jadranske haplogrupe. Najdominantniji haplotip u slivu Crnog Timoka i rekama desne obale Dunava u Đerdapskom regionu pripadao je dunavskoj liniji i opisan je pod imenom Da23c (ACCN KC630984). Obzirom da je ovaj haplotip zasada otkriven samo u ovoj oblasti i to sa velikom učestalošću smatra se autohtonim za ovu regiju. U okviru Đerdapskog regiona uočen je i haplotip Da1, ali samo u Rečkoj reci u njenom desnom delu iznad nepremostive prepreke, vodopada visine 10 m. Kao pleziomorfni u odnosu na haplotip Da23c i široko rasprostranjen na ovom delu Balkanskog poluostrva postoji velika verovatnoća da je i on autohton za ovo područje, međutim nije isključena ni mogućnost da je unesen poribljavanjem. U okviru sliva Crnog Timoka osim autohtonog haplotipa Da23c otkriven je i Da2, koji je najverovatnije alohton. U prilog tome govore činjenice o rasprostranjenju haplotipova na zapadnom Balkanu, kao i podaci o korišćenju jedinki ovog haplotipa za poribljavanje i gajenje u Austrougarskoj, a kasnije u celoj Evropi i Srbiji. Osim dunavske u okviru šireg područja Đerdapa otkriveno je i prisustvo atlanske linije u rekama Brnjica, Dobrinjska, Porečka i Vratna, a samo u poslednjoj jedinke atlanskog haplotipa koegzistiraju sa pastrmkama koje nose autohtoni haplotip, Da23c. Atlanski haplotip ne smatra se autohtonim za Balkansko poluostrvo, pa je najverovatnije u reku Vratnu dospeo poribljavanjem, a analize jedarnog gena, laktat dehidrogenaze, pokazale su da se ove jedinke međusobno ukrštaju. Programske analize podataka osam mikrosatelitskih lokusa ukazale su na postojanje pet izdvojenih populacija u regionu severoistočne Srbije: sliv Crnog Timoka, reka Kožica, reka Rečka, reke Vratna i Zamna zajedno i reke Mala Boljetinska i Zlatica zajedno, što ukazuje na verovatnu komunikaciju i protok gena između
ovih populacija. Mere upravljanja ovim ribolovnim područjima isključuju poribljavanje, jer trenutno ne postoji veštački mrest gde se koristi genetički materijal autohton za ovu oblast...Control Region of mitohondrial DNA is a good phylogeographic marker for brown trout species complex (Salmo cf. trutta). Five main brown trout phylogeographic lineages (haplogroups) that mostly correspond to the particular basins have been established at the end of 20th century: Danubian, Atlantic, Mediteranean, Adriatic and marmoratus. Individuals from Serbia held haplotypes of Danubian, Adriatic and Atlantic haplogroups. Prevailing haplotype in the River Crni Timok drainage area and in the right tributaries of the River Danube from Đerdap region is Da23c (ACCN KC630984) of Danubian haplogroup. This haplotype is considered indigenous there since it has been found only in this area and with a great frequency. Another haplotype also detected in the Đerdap region is Da1, but only in the River Rečka, in its right fork above the 10 m high waterfall, which is an impassable obstacle for upstream dispersal of brown trout from downstream section. Considering its plesiomorphic character compared to haplotype Da23c and its wide distribution in this part of Balkan Peninsula, there is a high probability that it is indigenous for this region, as well. However, the possibility that it has been imported by stocking activities cannot be excluded. In addition to the indigenous haplotype Da23c, the haplotype Da2 was also detected in the Crni Timok drainage area, probably as an allochthonous one. This was supported by haplotype distribution in Western Balkans, as well as by history of stocking and breeding with the Da2 haplotype in Austria-Hungary and later, both in middle and southeastern Europe, including Serbia. Individuals of the Atlantic haplogroup were detected in rivers Brnjica, Dobrinjska, Porečka and Vratna of the broader Đerdap area. Only in the last river these individuals coexist in sympatry with brown trout of indigenous Da23c haplotype. Since Atlantic haplotype was not considered indigenous for Balkan Peninsula, it has been probably introduced there by stocking. Analysis of nuclear gene lactate dehydrogenase showed that individuals of two lineages occurring in sympatry interbreed. Data software analyzes of eight microsatellite loci revealed the existence of five separated populations in Eastern Serbia: (1) Crni Timok drainage area, (2) River Kožica,
(3) River Rečka, (4) Rivers Vratna and Zamna, and (5) River Mala Boljetinska and River Zlatica, indicating a potential communication and gene flow between these populations..
Crystal growth of K2TiGe3O9 in the glass
The kinetics and mechanism of isothermal crystal growth of K2TiGe3O9 from a glass of the same stoichiometric composition were studied. The crystal growth rate U = 1 x 10-11-1.27 x 10-10 m s-1 was experimentally determined in the temperature interval of t = 540-600°C. In the range of high undercooling, Δt=435-375°C, spherical crystals growing at (374 ± 19) kJ mol-1 was observed
Dielectric Permeability of Nanocylinder
In the nanocylinder, a cut-off from the molecular crystal, dielectric permeability tensor is investigated. Excitons in the nanocylinder arise due to the exciting of the electron subsystem of the molecule. In evaluation of dielectric permeability Dzhyaloshinskii-Pitaevskii approach is used, connected with retarded and advanced exciton Green's functions and correct use of Paulion Green's function. It turned out that refraction and absorption indices depend on configuration coordinates, having maximal values at boundary cross-sections and minimal value at central cross-section of the nanocylinder broken symmetry structure. Although it was expected that boundary conditions make higher refractive and absorptive characteristics of the nanocylinder, this appeared not to be possible because Paulion Green's function is not proportional to the exciton concentration
Risk assessment of non-native fishes in the Balkans Region using FISK, the invasiveness screening tool for non-native freshwater fishes
A high level of freshwater fish endemism in the Balkans Region emphasizes the need for non-native species risk assessments to inform management and control measures, with pre-screening tools, such as the Fish Invasiveness Screening Kit (FISK) providing a useful first step. Applied to 43 non-native and translocated freshwater fishes in four Balkan countries, FISK reliably discriminated between invasive and non-invasive species, with a calibration threshold value of 9.5 distinguishing between species of medium and high risk sensu lato of becoming invasive. Twelve of the 43 species were assessed by scientists from two or more Balkan countries, and the remaining 31 species by a single assessor. Using the 9.5 threshold, three species were classed as low risk, 10 as medium risk, and 30 as high risk, with the latter category comprised of 26 moderately high risk, three high risk, and one very high risk species. Confidence levels in the assessments were relatively constant for all species, indicating concordance amongst assessors
Anthocyanin-functionalized biopolymer films as pH-sensitive indicators
Anthocyanins are water-soluble, non-toxic flavonoid pigments, which produce the blue, red and purple color of many plants. Color change of anthocyanin extracts is a direct consequence of the transformation of their chemical structure when exposed to different pH conditions. Optical properties investigated in UV-Vis absorption and PL spectra show a clear difference between anthocyanins in acidic and in alkaline environments. Chitosan, a natural-based, non-toxic and biodegradable polysaccharide, is chosen as an ideal matrix for nanocomposites. It is proven to be a good carrier for anthocyanins, because of its ability to entrap the indicator dyes and at the same time the ability to release anthocyanins when in contact with an acidic environment. In this research, we have developed anthocyanin-enhanced biopolymer indicator systems, which provide fast colorimetric response to alterations in pH levels of the environment. Transmittance spectra of nanocomposites show excellent light-blocking properties of the films. This opens up possibilities for advancement in future technology of smart biodegradable food packaging biomaterials. The availability of innovative and healthy materials reduces the need for using synthetic plastic in the modern food industry.IX International School and Conference on Photonics : PHOTONICA2023 : book of abstracts; August 28 - September 1, 2023; Belgrad
SATURN D6.5 - Final Report
The objective of the SATURN (Strategic Allocation of Traffic Using Redistribution in the Network) project is to make novel and credible use of market-based demand-management mechanisms to redistribute air traffic in the European airspace. This reduces congestion and saves the airspace users operational costs.
The project is motivated by frequent demand and capacity imbalances in the European airspace network, which are forecast to continue in the near future. The present and foreseen ways of dealing with such imbalances mainly concern strategic and tactical capacity-side interventions, such as resectorisation and opening of more sectors to deal with excess demand. These are followed by tactical demand management measures, if needed. As a result, not only do substantial costs arise, but airspace users are also typically left with no choice but to comply with imposed air traffic flow management measures.
The project shows how economic signals could be given to airspace users and air navigation service providers (ANSPs) to improve capacity-demand balancing, airspace design and usage, and what the benefits would be of a centralised planner compared with those of decentralised maximisation of self interests (by the ANSPs and/or airspace users)
IRON CONTENT IN THE FRUITS OF THE GRAPEVINES AND PEACH TREES GROWING NEAR THE MINING AND SMELTING COMPLEX BOR, EAST SERBIA
The samples of fruits of the grapevine (Vitis vinifera, cultivar Tamjanika) and the peach tree (Prunus persica L. Batech) from the Bor region were analyzed using an ICP-OES to determine the content of iron (Fe). This was done in order to assess possible health risks related to this essential element; the region of Bor’s municipality is known as one of the most polluted areas in Serbia. The content of Fe in unwashed grapes seems not to be affected by the mining/metallurgical activities, as it was either in the normal concentration range or was at even lower than critical deficiency concentration in plants (21.8-98 mg/kg). The level of Fe in the samples of peaches ranged from 62.4 to 1418 mg/kg, which is much higher than that in grape samples and in one case, even higher than the phytotoxic threshold. The values of the enrichment factor (EF) were lower than 2 in the case of grape samples, while for peach samples, these values ranged from rather low (0.99) to extremely high (22.66). Based on the herein obtained results, in the region of Bor, it seems that the cultivation of grapevine should be favored over the cultivation of peach trees.SADRŽAJ GVOŽĐA U PLODOVIMA VINOVe LOZe I BRESKVE KOJE RASTU U BLIZINI RUDARSKO-TOPIONIČARSKOG KOMPLEKSA BOR, ISTOČNA SRBIJAUzorci plodova vinove loze (Vitis vinifera, sorta Tamjanika) i vinogradarske breskve (Prunus persica L. Batech) iz regiona Bora su analizirani metodom ICP-OES, kako bi se odredio sadržaj gvožđa (Fe). Analize su vršene da bi se procenio mogući zdravstveni rizik povezan sa ovim esencijalnim elementom; poznato je da je region Borske opštine jedan od najzagađenijih predela u Srbiji. Čini se da rudarsko-metalurške aktivnosti ne utiču na sadržaj Fe kod vinove loze, jer je isti bio ili u okviru koncentracija normalnih za većinu biljaka ili čak niži od kritične koncentracije deficijencije (21.8-98 mg/kg). Koncentracija Fe u uzorcima breskve je bila u opsegu od 62.4-1418 mg/kg, što je mnogo više nego u uzorcima grožđa i u jednom slučaju čak iznad granice fitotoksičnosti. Vrednosti faktora obogaćenja bile su manje od 2 u slučaju uzoraka grožđa, dok su se kod uzoraka breskve ove vrednosti kretale od niskih (0,99) do ekstremno visokih (22,66). Na osnovu dobijenih rezultata, u borskom regionu, čini se da bi se trebalo forsirati uzgoj grožđa u odnosu na uzgoj breskve. HIGHLIGHTS Iron (Fe) represents one of the key constituents of particulate matter originating from the copper smelter plant in Bor.The influence of anthropogenic activities on the Fe content in the investigated fruits was more obvious and more considerable in the case of peach samples.The concentration of Fe in peach samples was much higher than in grapes, and in one case even higher than the phytotoxic threshold.The content of Fe in grapes was in the range of normal concentrations in plants or, in many cases, lower than the critical deficiency concentration
Pine Pitch Canker and Insects: Regional Risks, Environmental Regulation, and Practical Management Options
Producción CientíficaPine pitch canker (PPC), caused by the pathogenic fungus Fusarium circinatum (Nirenberg
and O’ Donnell), is a serious threat to pine forests globally. The recent introduction of the pathogen to Southern Europe and its spread in Mediterranean region is alarming considering the immense
ecological and economic importance of pines in the region. Pines in forests and nurseries can be
infected, resulting in severe growth losses and mortality. The pathogen is known to spread in plants
for planting and in seeds, and results from recent studies have indicated that F. circinatum may also
spread through phoretic associations with certain insects. With this review, we aim to expand the
current understanding of the risk of insect-mediated spread of PPC in different parts of Europe.
Through the joint action of a multinational researcher team, we collate the existing information about
the insect species spectrum in different biogeographic conditions and scrutinize the potential of
these insects to transmit F. circinatum spores in forests and nurseries. We also discuss the impact of
environmental factors and forest management in this context. We present evidence for the existence of
a high diversity of insects with potential to weaken pines and disseminate PPC in Europe, including
several common beetle species. In many parts of Europe, temperatures are projected to rise, which
may promote the activity of several insect species, supporting multivoltinism and thus, further
amplifying the risk of insect-mediated dissemination of PPC. Integrated pest management (IPM)
solutions that comply with forest management practices need to be developed to reduce this risk.
We recommend careful monitoring of insect populations as the basis for successful IPM. Improved
understanding of environmental control of the interaction between insects, the pathogen, and host
trees is needed in order to support development of bio-rational strategies to safeguard European pine
trees and forests against F. circinatum in future.European Cooperation in Science and Technology (COST Action FP1406 PINESTRENGTH)Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project AGL2015-69370-R)Portuguese Foundation for Science and Technology (contract IF/00471/2013/CP1203/CT0001)Russian Foundation for Basic Research (grant 17-04-01486)Saint Petersburg State Polytechnical University (project 2019-0420
A guided tour of asynchronous cellular automata
Research on asynchronous cellular automata has received a great amount of
attention these last years and has turned to a thriving field. We survey the
recent research that has been carried out on this topic and present a wide
state of the art where computing and modelling issues are both represented.Comment: To appear in the Journal of Cellular Automat
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