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Courtship in Drosophila involves exchange of chemosensory, auditory, tactile and visual signals. Differences in courtship signals are strongly influenced by environmental factors, among which nutrition plays one of the more important roles. Through influence on development, morphology, physiology and behaviour, nutrition may affect both sexual selection and isolation. However, the impact of specific nutritive regimes on male mating success has not been extensively studied. Therefore, the aim of this study was to explore how diets affect male attractiveness via changes in wing morphology during long-term rearing of flies on different diets. Through a series of female choice tests, we investigated the mating success of males reared on five different diets for more than 350 generations. Further, we analysed wing size and wing shape of mated and unmated males to link wing morphology with mating success. The results demonstrate significant differences in male mating success between strains. We also found significant differences in wing size between the strains and established that female choice is positively correlated with male wing size, that is, females of all strains preferred males with larger wings. In addition, we noted a significant difference in wing shape between the strains, as well as between mated and unmated males. Our results indicated that among strains, males with elongated wings were more successful in mating than males with rounded wings. Within strains, mated males had more elongated wings than unmated ones, which had more rounded wings. Our results support the hypothesis that nutrition represents an important environmental factor that may affect male attractiveness via changes in wing morphology, thereby playing an important role in sexual selection of Drosophila melanogaster.

Drought directly and indirectly affects human society in a number of ways. In many regions of the world climate change will exasperate the effects of droughts, affect national economies more intensely. The main aim of this article was to catalogue and analyze the drought impacts in the 11 Central and South Eastern European states located in the Danube river basin. The identification of dry episodes was based on information from publicly available sources, namely, newspaper and journal articles that reported drought impacts. Information on drought impact occurrences was classified into one of five defined categories in which the drought impact report was most clearly manifested (i.e., agriculture, forestry, soil systems, wildfires and hydrology). In terms of the spatial distribution of drought impacts, individual recorded events were analyzed at the level of EU NUTS regions (or their equivalent in non-EU countries). The analysis highlights country-specific vulnerability to drought. Furthermore, gradual increases in drought events and the number of reported impacts were identified, which was particularly evident in the agricultural sector.

Nickel-alumina composites with various content of nickel were synthetized by sol-gel method. The characterization of samples was performed by diffuse reflectance spectroscopy and electrochemical impedance spectroscopy using the Mott-Schottky analysis. Glassy carbon electrode modified by synthesized composites was investigated for reduction of 4-nitrophenol. Modification of glassy carbon electrode with composite sample led to the strong apparent electrocatalysis. Principal component analysis was used to establish correlation between structural, textural and electrochemical data of investigated composites.

Hexagonal ZnIn2S4 is synthesized by simple and low-cost hydrothermal route. TEM images revealed formation of nanosheets. The estimated band-gap energy of synthesized sample is in the visible spectral region and has a value of about 2.25 eV. Photocatalytic properties of synthesized sample are probed in photocatalytic degradation of three selected dyes different in nature and structure, Rhodamine B (RhB), Methylene blue (MB) and Methyl orange (MO), under the illumination with simulated Solar light. Obtained results revealed that photocatalytic degradation of RhB and MO is mainly result of synergic effect of photogenerated holes and oxygen, while primary effect in ZnIn2S4/MB system is bleaching of the dye, but no photodegradation was observed. © 2019 Elsevier B.V.

In Serbia, Branchipus Schaeffer, 1766 is especially common in the Pannonian lowlands, where Branchipus schaefferi and Branchipus serbicus were previously reported. In the southern parts of the country, at the foothills of the Stara Planina Mountains, a Branchipus intermedius population is reported to occur. We used multivariate analysis to assess the degree of morphological variability between Branchipus populations currently ascribed to different species. Morphometric characters contributed the most to the morphological differentiation. Populations were better defined on the basis of male morphometric characters. Our results indicate that individuals from the southeastern, mountainous part of the country had the highest level of differentiation. We confirmed that this population belongs to B. intermedius. The individuals of the presumed species B. serbicus exhibited a fairly lower level of morphological differentiation in the present study, and grouped together with other lowland Serbian populations ascribed to B. schaefferi. According to this study, B. serbicus is a junior synonym of B. schaefferi. This is a post-peer-review, pre-copyedit version of an article published in Hydrobiologia. The final authenticated version is available online at: [http://dx.doi.org/10.1007/s10750-017-3286-0]

Hot-injection method for synthesis of ZnIn2S4 (ZIS) in organic media was studied. Nanosized ZnIn2S4 is successfully synthesized in oleic acid/oleylamine mixture in different ratios, which are both: complexing and/or capping agents. Nanosheets/nanoscrolls of about 50 nm are obtained. The band gaps of synthesized nanostructures were calculated to be in the range from 2.6 to 3.0 eV, values which are increased compared to bulk value (2.3-2.5 eV). The increase of band gap can be assigned to nanodimensions of the particles. Potential of band edges is calculated using empirical equation and find to be in the range from -0.16 to -0.36 V for conduction band, and from 2.24 to 2.69 V for valence band. By using XRD and TEM techniques, crystal structure and morphology of obtained materials were investigated, and detailed formation and growth mechanism of nanosheets/nanoscroles is proposed accordingly. (C) 2016 Elsevier Ltd. All rights reserved.

The influence of deposition and annealing parameters on optical, structural and photocatalytic properties of N-doped titanium-dioxide (TiO2) thin films have been studied. Anatase and anatase-rutile crystalline phase mixture TiO2 thin films were obtained depending on the reactive direct current (DC) sputtering and annealing conditions. Deposition in the nitrogen atmosphere produced N-doped TiO2 thin films with energy gap values shifted towards visible region in comparison with thin TiO2 films deposited without nitrogen in the atmosphere. The role of substitutional and interstitial nitrogen atoms incorporated in obtained crystalline structures during the deposition was shown important and was reflected in the efficiency of photocatalysis. It was found that thin TiO2 films with more substitutional incorporated nitrogen exhibits better photocatalytic properties. These results could be of importance towards achieving controlled synthesis of N-doped TiO2 thin films with desired structural and optical properties, especially with improved photo-activity in the visible part of the solar spectrum.

Job division according to gender is, in its roots, of social and cultural character. Gender characteristics, cultural heritage and system of values in their living and working environment, have influenced women rather than men, in their professional development and progress within leadership hierarchy in organizations. This study is focused on a problem of women's professional promotion. The basic assumption is that positioning a woman in managerial structure of an organization, is influenced by a group of sociocultural factors such as social background, residential location, level of education and close environment which defines individual's action, recognition, understanding and evaluation of information, motives and achievements. These bundle of sociocultural factors have been referred to as an individual cultural capital. The main aim is to identify and analyze supportive and non-supportive factors, within the set of explored sociocultural factors, a woman faces on her way up the managerial hierarchy as well as to find possibilities to manage relevant factors in order to enable the woman to fully realize her professional potential and reach the highest possible level at managerial hierarchy. The findings prove relevance of explored factors and their influence on woman's professional promotion.

Solvothermal synthesis of ZrO2-TiO2 binary oxides and pure counterparts at 150 degrees C in water/isopropanol media is presented. Titanium (IV) isopropoxide and zirconium (IV) propoxide were used as precursors. XRD and TEM techniques were used for structural and morphological characterization of obtained samples. XPS spectra of mixed oxide samples were compared in order to correlate composition of samples with surface properties and presence of defects. Relative positions of defect states within band-gaps of semiconductors were estimated from UCPL spectra. UV-Vis DRS spectra revealed that both pure oxides experienced red shift of absorption thresholds compared to reference data. Photocatalytic activities of all samples were probed under simulated Solar light on three model compounds: phenol, 4-chlorophenol (4-CP) and 2, 4, 6-trichlorphenol (TCP). Pure TiO2 showed the highest photocatalytic activity in the case of phenol. However, pure ZrO2 and binary oxides showed higher photoactivity in degradation of 4-CP and TCP. The activity of wide band-gap semiconductors under simulated Solar light in photodegradation of phenol and its derivatives is most probably the consequence of formation of charge transfer complexes between pollutant molecules and semiconductors surface. This is the peer-reviewed version of the aricle: Carević, M. V., Abazović, N. D., Savić, T. D., Novaković, T., Pjevic, D. J.,& Čomor, M. (2018). Binary oxide ceramics for enhanced phenols degradation under simulated Solar light. Journal of the American Ceramic Society, Wiley, Hoboken., 101(4), 1420-1431. [https://doi.org/10.1111/jace.15324] The published version: [https://cer.ihtm.bg.ac.rs/handle/123456789/2466]

Sensitization of TiO2 crystals and nanoparticles with appropriately chosen organic molecules can lead to a significant shift of their absorption threshold from the UV to the visible, thus improving the absorption of the solar spectrum as well as the efficiency of photocatalytic and photovoltaic devices. Herein, the surface modification of nanocrystalline TiO2 particles (45 angstrom) with salicylate-type ligands consisting of an extended aromatic ring system, specifically 1-hydroxy-2-naphthoic acid and 1,4-dihydroxy-2-naphthoic acid, was found to alter the optical properties of nanoparticles in a similar way to salicylic acid. From both absorption measurements and steady-state quenching measurements of modifier fluorescence upon binding to TiO2 in methanol/ water = 90/10 solutions, stability constants in the order of 10(3) M-1 have been determined at pH 2. Fluorescence lifetime measurements, in the presence and absence of colloidal TiO2 nanoparticles, indicated that the fluorescence quenching process is primarily static quenching, thus proving the formation of a nonfluorescent charge-transfer (CT) complex. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TPD analysis (TG/DTA/MS). Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of a salicylate type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. The formation of the inner-sphere CT-complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction in the band gap upon the increase in the electron delocalization when including an additional ring. Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3337]

Over the past century, man-made electromagnetic fields (EMF) have changed the natural environment, representing one of the most common and rapidly increasing environmental factors as technology advances. Numerous studies of biological effects of exposure to EMF have been performed on Drosophila during the last 30 years, showing contrasting results. In an attempt to determine whether EMF exposures might affect the development of Drosophila, the present study examines phenotypic variations through direction and range of changes in several fitness components and wing length and width, of Drosophila subobscura isofemale lines, affected by 50 Hz EMF. Embryonal and early post-embryonal stages were exposed to homogeneous sinusoidal 0.25 mT EMF of 50 Hz. The EMF exposure caused a significantly prolonged developmental time and significantly increased the wing size with the opposite direction of directional asymmetry compared to the control group. These results shows that even such a weak EMF has the potential to modulate, through developmental pathways, some of the fitness-related traits, wing size, and wing asymmetry in D. subobscura even after one generation of exposure, showing that extremely low frequency (ELF) EMFs have relevant consequences on development, adult morphology, and fitness. Ministry of Education, Science and Technological Development, Republic of Serbia {[}173012]

In recent years, it is widely accepted that bioactive compounds of fruits and vegetables are related to reduction of oxidative stress, thus having the beneficial effect of decreasing the risk of many human diseases. The aim of the present study was to evaluate the possible protective effects of Aronia melanocarpa fruit extract. This in vivo study was conducted using fruit fly (Drosphila melanogaster) larvae. Simultaneously with treatments, co-treatments with the same concentrations of aronia fruit extract mixed with a strong mutagen, methyl methanesulphonate (MMS), were performed. Fitness traits and morphological characters were monitored. Positive biological effects were observed in flies that developed on substrates with 2% and 25% A. melanocarpa extract. Only a mixture of MMS+25% fruit extract showed preferable effects both on fitness components and on wing development in comparison with other MMS co-treatments, indicating the ability of this concentration to protect the cells from MMS-induced damage.

Evolution of reproductive isolation may be a consequence of a variety of signals used in courtship and mate preferences. Pheromones play an important role in both sexual selection and sexual isolation. The abundance of pheromones in Drosophila melanogaster may depend on different environmental factors, including diet. The aim of this study was to ascertain to which degree principal pheromones affect sexual selection in D. melanogaster. We used D. melanogaster strains reared for 14 years on four substrates: standard cornmeal substrate and those containing tomato, banana and carrot. We have previously determined that long-term maintaining of these dietary strains resulted in differences in their cuticular hydrocarbons profile (CHs). In this work, we have tested the level of sexual selection and sexual isolation between aforementioned strains. We found that the high levels of cis-vaccenyl acetate, 7-pentacosene and 7,11-nonacosadiene in the strain reared on a substrate containing carrot affected the individual attractiveness and influenced sexual isolation between flies of this strain and flies reared on a substrate containing banana. Based on these results, long-term different diets, may contribute, to sexual behaviour of D. melanogaster via the effects of principal pheromones. Behavioural Processes (2017), 140: 81-86

Purpose: Extremely low frequency (ELF) magnetic fields as essential ecological factors may induce specific responses in genetically different lines. The object of this study was to investigate the impact of the ELF magnetic field on fitness components and locomotor activity of five Drosophila subobscura isofemale (IF) lines. Materials and methods: Each D. subobscura IF line, arbitrarily named: B16/1, B24/4, B39/1, B57/2 and B69/5, was maintained in five full-sib inbreeding generations. Their genetic structures were defined based on the mitochondrial DNA variability. Egg-first instar larvae and 1-day-old flies were exposed to an ELF magnetic field (50 Hz, 0.5 mT, 48 h) and thereafter, fitness components and locomotor activity of males and females in an open field test were observed for each selected IF line, respectively. Results: Exposure of egg-first instar larvae to an ELF magnetic field shortened developmental time, and did not affect the viability and sex ratio of D. subobscura IF lines. Exposure of 1-day-old males and females IF lines B16/1 and B24/4 to an ELF magnetic field significantly decreased their locomotor activity and this effect lasted longer in females than males. Conclusions: These results indicate various responses of D. subobscura IF lines to the applied ELF magnetic field depending on their genetic background. This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Radiation Biology on 2018-01-12, available online: [http://www.tandfonline.com/10.1080/09553002.2017.1268281]. Related to: [http://ibiss-r.rcub.bg.ac.rs/handle/123456789/3781]

The surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands having different electron donating/electron withdrawing substituent groups, specifically 3-methylcatechol, 4-methylcatechol, 3-methoxycatechol, 3,4-dihydroxybenzaldehyde and 4-nitrocatechol, was found to alter the optical properties of nanoparticles in a similar way to catechol. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction of the effective band gap, being slightly less pronounced in the case of electron withdrawing substituents. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of the catecholate type (binuclear bidentate binding-bridging) thus restoring six-coordinated octahedral geometry of surface Ti atoms. From the absorption measurements (Benesi-Hildebrand plot), the stability constants in methanol/water = 90/10 solutions at pH 2 in the order of 10(3) M-1 have been determined. The binding structures were investigated by using FTIR spectroscopy. Thermal stability of CT-complexes was investigated by using TG/DSC/MS analysis. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.

A study of photocatalytic activity of bare as prepared, bare aged and dopamine surface modified colloidal TiO2 nanoparticles was obtained following degradation reaction of herbicide RS-2-(4-chloro-o-tolyloxy)propionic acid under UV light irradiation. Results showed that the most active photocatalyst is bare aged TiO2 and the least active are dopamine modified nanoparticles. Results are discussed in the light of surface structure of TiO2 nanoparticles. The study of surface modification of TiO2 nanoparticles (4.5 nm, TiO2 NPs) with dopamine was also performed. The formation of inner-sphere charge-transfer complexes results in red shift of semiconductor absorption threshold (600 nm), compared to bare TiO2 NPs (380 nm). Effective band gap energy of 3.2 eV for bare TiO2 NPs is reduced to 2.1 eV for TiO2/dopamine charge transfer complexes. The binding structure was investigated by UV-vis and FTIR spectroscopy. The obtained optimal geometry for binding of dopamine to surface Ti atoms was binuclear bidentate-bridging. From the Benesi-Hildebrand plot, stability constant of the order 10(3) M-1 has been determined. (C) 2013 Elsevier B.V. All rights reserved.

ZnO/ZnWO4 composite rod-like nanoparticles were synthesized by low-temperature soft solution method at 95 A degrees C with different reaction times (1-120 h), in the presence of non-ionic copolymer surfactant Pluronic F68. Obtained nanoparticles had diameters in the range around 10 nm and length of 30 nm. Optical properties such as reflection and room temperature photoluminescence of obtained samples showed strong dependence on their crystallinity and composition. Photocatalytic activity of ZnO/ZnWO4 nanopowders was checked using photodegradation of selected dyes as model system. Obtained results were correlated with specific surface area, particle sizes, crystallinity and ZnO/ZnWO4 ratio of the samples. As crystallinity of ZnWO4 component in the ZnO/ZnWO4 increase, photocatalytic activity also increases. The main findings can be explained by charge transfer reactions that follow light absorption by ZnO and ZnWO4 in nanocomposite.

Different environmental factors are important for development, physiology, behaviour and, therefore, adaptation of Drosophila species. Additionally, the presence of genetic and phenotypic variation in traits affecting mate choice forms the basis for sexual selection that may lead to isolation between populations in different nutritive environments. The aim of this research was to determine mating success and wing morphometry of Drosophila melanogaster flies after more than a decade of growing on banana and carrot substrates. Males and females reared on carrot medium were more successful in mating than flies reared on banana diet. Females originating from banana medium rather chose males originating from carrot substrate, while females developed on carrot medium equally chose males developed on both substrates. Differences in wing size and shape were observed between sexes and nutritional strains. Furthermore, the results showed absence of ethological isolation between two 'nutritional' strains. Serbian Ministry of Education, Science and Technological Development [173012]

The aim of this research was to examine the temporal patterns of spontaneous locomotor activity in Drosophila subobscura virgin females and males from isofemale lines collected from beech and oak forests and maintained in controlled laboratory conditions for five full-sib inbreeding generations. The flies were monitored in a circular open field arena for 30 min in the morning (8:00 AM, 9:00 AM, 10:00 AM, 11:00 AM). The distance travelled and the mobility of the flies decreased along with the registration time, whereby the slowest decreasing was observed at 8:00 AM. Females showed a greater range of variability in both parameters compared to males. In addition, there was a greater range of variability in the locomotor activities of flies from the oak forest compared to the beech. These findings could be attributed to their specific genetic background. [Projekat Ministarstva nauke Republike Srbije, br. 173012]

We report the successful, low temperature synthesis of pure and Fe-doped titania nanoparticle (NP) powders, using organic Ti- and Fe-precursors. The properties of the synthesized titania based materials were obtained using XRD, UV/vis and EPR spectroscopy and BET measurements. The doping of TiO2 induced a shift in the absorption threshold towards the visible spectral range, compared to pure titania. The process of annealing induced an increase in crystallinity and particle sizes in the obtained materials. The photocatalytic activity, using simulated Solar light (Vitalux lamp), of our samples was checked by following the photodegradation reaction of Rhodamine B and trichlorophenole as model compounds. This is the peer-reviewed version of the article: Carević, M., Abazović, N. D., Savić, T. D., Novaković, T., Mojović, M.,& Čomor, M. (2016). Structural, optical and photodegradation properties of pure and Fe-doped titania nanoparticles probed using simulated Solar light. Ceramics International, Elsevier Sci Ltd, Oxford., 42(1), 1521-1529. [https://doi.org/10.1016/j.ceramint.2015.09.100] The published version: [https://cer.ihtm.bg.ac.rs/handle/123456789/1982]

Zinc oxide (ZnO)/zinc tungstate (ZnWO4) rod-like nanoparticles with diameters in the range of 6-11 nm and length of about 30 nm were synthesized by a low temperature soft solution method at 95-C in the presence of non-ionic copolymer surfactant. It was found that their crystallinity was enhanced with the increase of heating time from 1 h up to 120h. The photoluminescence (PL) measurements showed very strong, narrow UV band peaked at 3.30 eV and a broad visible band peaking at 2.71 eV with a shoulder at about 2.53 eV, for lambda(exc) LT 300 nm. Quite large variations in the intensities of the two PL bands were observed for different excitation wavelengths. The intensity of the main visible band decreases with decreasing excitation energy and disappears when samples are excited lambda = 320 nm (E-exc = 3.875 eV). We found that observed optical properties originate from ZnO phase. UV band gap PL had high intensity for all applied excitations, probably induced by ZnWO4 phase presence on the surface. In addition, two values were found for direct band-gap energy of ZnO/ZnWO4 rod-like nanoparticles 3.62 and 3.21 eV, determined from reflectance spectrum. The photocatalytic behaviour of ZnO is strongly dependent on the formation of ZnWO4 phase, of the obtained rod-like nanoparticles. (C) 2012 Elsevier B.V. All rights reserved.

In the present study, developmental stability of leaf traits was examined in three natural populations of Plantago major L. (ssp. major), representing two polluted environments (Karaburma and Zemun) and an unpolluted area (Crni Lug). Developmental stability was assessed as fluctuating asymmetry (FA). The magnitude of FA is believed to reflect differences in the ability of individuals to buffer their development in natural populations. We hypothesized that there are differences within characters and among characters in response to environmental conditions. Significant patterns of asymmetry correlations and asymmetry changes were detected both within characters and between characters. The manova results revealed a significant effect of individual and a significant individual × environment interaction on actual asymmetry (logLi − logRi) and on the amount of asymmetry |(logLi − logRi)| for leaf width and vein distances within a leaf. Over time, statistically significant and positive correlations of the FA values were detected for each trait separately per sample (population). For both leaf traits, there were differences for (logLi − logRi) and |(logLi − logRi)| asymmetry values among individuals within samples in response to yearly variations. Statistically significant and negative correlations for (logLi − logRi) versus |(logLi − logRi)| asymmetries were detected for both leaf traits. In summary, our results highlight the importance of differences in the ability of individuals to buffer their development under different environmental conditions and point to the concept that developmental stability is character specific.

In this study, a static magnetic field influence on development and viability in two different species, Drosophila melanogaster and Drosophila hydei, was investigated. Both species completed development (egg--adult), in and out of the static magnetic field induced by double horseshoe magnet. Treated vials with eggs were placed in the gap between magnetic poles (47 mm) and exposed to the average magnetic induction of 60 mT, while control ones were kept far enough from magnetic field source. We found that exposure to the static magnetic field reduced development time in both species, but statistical significance was found only for D. hydei. Furthermore, we found that the average viability of both Drosophila species exposed to the magnetic field was significantly weaker compared to control ones. These results indicate that 60 mT static magnetic field could be considered as a potential stressor, influencing on different levels the embryonic and post-embryonic development of individuals. Ministry of Education and Science Development, Republic of Serbia [173012, 173027]

Due to the direct interaction between enzyme and substrate, the amylase system can provide valuable information on the relationship between homozygosity and developmental homeostasis under a changing environment in several Drosophila species, The adaptive significance of the relationship between genetic variability and environmental change manifests through the well-known polymorphism of the amylase locus (Amy). We examined the effect of gradual and abrupt changes in starch concentration in the nutritional substrate, on the developmental time, egg-to-adult viability and phenotypic plasticity in the progeny of Drosophila subobscura that was homozygous for ?fast? (AmyF/AmyF) and ?slow? (AmyS/AmyS) Amy alleles. Our findings show that gradual and abrupt nutritional changes exert a significant effect on developmental time and viability. A high heterogeneity among genotypes in fluctuating asymmetry (FA) and no direct association between FA and fitness components under the two experimental regimes of environmental change were observed.

The Amy locus polymorphism of Drosophila subobscura is used as a model system for an experimental population genetic study of adaptive significance of α-amylase activity on substrates of different carbohydrate compositions. So far, fitness components have not commonly been included in ecological-genetic studies of α-amylase polymorphism in this species. In the present paper, fitness components are analyzed in relation to different amylase activities in D. subobscura individuals homozygous for the “slow” and the “fast” Amy allele, associated with substrates of different carbohydrate compositions. The results indicate a significant effect of substrate carbohydrate composition on fitness components of the genotypes homozygous for S or F Amy allele in D. subobscura through their enzyme activity.

We assessed the variation in thorax size, wing size and wing loading in populations of Drosophila subobscura from two ecologically different habitats and within each habitat sampled during three periods of the day. The traits analyzed differed between laboratory reared samples and field collected samples. Differences were mainly caused by environmental factors and genotype x environmental interactions. While there were no significant differences between populations for particular periods of the day, within-population analysis for each sex showed specific differences. Results showed that wing loading was the least variable character in natural populations, also showing the lowest level of sexual dimorphism. The data are discussed from the aspect of the variability of gene arrangement frequencies over daytime periods obtained previously for the same samples. They are consistent with models of maintenance of genetic variability in multi-niche habitats, and are in favour of a type of reactive behaviour dependent on ecological niche qualities on a daily rhythm scale in D. subobscura.

We analyzed changes in the genetic structure of two ecologically distinct populations of Drosophila subobscura by assessing inversion polymorphism parameters for over years. The frequencies of gene arrangements on all five chromosomes show variability in each population. Several chromosomal arrangements appeared for the first time in both populations. Significant difference in the overall distribution of gene arrangements between first and last year of study (1998/2006) in beach wood population of D. subobscura is found for chromosome A (a sex chromosome) and autosomes J and E, while in oak wood population the overall frequency of gene arrangements differ for autosomes J, E and O. The present significant changes of the particular gene arrangements are specific for each population and result in significant differences in comparisons at the level of individual chromosomes between years of study. Although overall heterozygosity remained unchanged over the years in beech habitat, it is significantly reduced in oak population in the fourth year. The obtained results indicate that population structure may significantly depend on short-term and long-term microclimatic changes in habitats. Based on the results to date, monitoring of microevolutionary changes using D. subobscura and its relatives seems a promising way to study the effects of global changes. .

Cuticular hydrocarbons (CHCs) in Drosophila melanogaster represent the basis of chemical communication being involved in many important biological functions. The aim of this study was to characterize chemical composition and variation of cuticular profiles in five D. melanogaster strains. These strains were reared for approximately 300 generations on five diets: standard cornmeal medium and substrates prepared with apple, banana, tomato, and carrot. Differences in quantity and/or quality in CHCs were assumed as a result of activation of different metabolic pathways involved in food digestion and adaptations to the particular diet type. In total, independently of sex and strain, 66 chemical compounds were identified. In females of all strains, 60 compounds were identified, while, in males, 47 compounds were extracted. Certain new chemical compounds for D. melanogaster were found. MANOVA confirmed that CHC amounts significantly depend on sex and substrates, as well as on their interactions. Discriminant analysis revealed that flies belonging to 'apple' and 'carrot' strains exhibited the most noticeable differences in CHC repertoires. A non-hydrocarbon pheromone, cis-vaccenyl acetate (cVA) also contributed to the variation in the pheromone bouquet among the strains. Variability detected in CHCs and cVA may be used in the explanation of differences in mating behaviour previously determined in analyzed fly strains.

In this work, the ostracod Heterocypris incongruens (Ramdohr, 1808) was used to analyse three of its behavioural activities (feeding, swimming and resting) and its food preference. The majority of the individuals spent their time swimming. However, towards the end of the experiment, the number of individuals found feeding increased. The overall time spent feeding throughout the experiment was significantly longer than the time spent swimming and resting. Spinach was the most frequently used food, followed by mosquito larvae, Cyclops (plankton mix) and Spirulina mix. The retention time spent in the compartment containing spinach was also significantly longer than the time spent on all other items. Serbian Ministry of Education, Science and Technological Development {[}176019]

Metamorphosis time (pupa to adult eclosion time) and adult lifespan were observed in an alternating, sinusoidal, magnetic field, and compared to control. Pupae of the housefly, Musca domestica (Diptera), of approximately the same age were chosen randomly (groups of 50 individuals) and individually placed in separate glass tubes (70 mm × 11 mm) without food. The group exposed to an electromagnet (50 Hz, 6 mT) with poles of 9.3 cm × 4.8 cm (area 44.6 cm2), spaced at 7.2 cm, was placed with the magnet at a sufficient distance from the control group where the experimental magnetic field effects were not detected. The experiments were carried out successively at temperatures of 19°C and 24°C, and a 12 h light/12 h dark regime, with a controlled 60–70% relative humidity. The results show that the magnetic field significantly slowed down metamorphosis at both temperatures. The adult lifespan in the magnetic field at 24°C was statistically significantly extended with respect to control, whereas the same lifespan in the magnetic field at 19°C showed no statistically significant shortening.

Egg-to-adult viability is studied in the progeny of the flies of different genotypes according to S and F alleles of Amy locus of Drsophila subobscura . This component of fitness is observed in the single and mixed cultures with various frequencies of three genotypes (S/S, F/F and S/F) under conditions of low (LD) and high densities (HD) on three types of media with different carbohydrate composition. In such multifactorial experimental conditions, density- and frequency-dependent selection on certain Amy genotypes was observed. Genotype frequencies and carbohydrate composition have significant effect on the viability of Amy genotypes. The significant intergenotypic differences exist, mostly at HD conditions. The heterozygous genotype S/F has generally lower viability which decreases with its increased frequencies, on all media at LD or HD. The results suggest a high level of complexity and interaction between these two types of balanced selection. Zusammenfassung In der Nachkommenschaft von Fliegen verschiedenen Genotyps fur die S- und F-Allele des Amy Locus wird die Uberlebensrate vom Ei bis zur Imago untersucht. Diese Fitness-Komponente wird in Experimenten mit nur einem oder mit gemischten Genotypen bei verschiedenen Frequenzen der drei moglichen Genotypen (S/S, F/F, und S/F), unter den Bedingungen niedriger oder hohe Dichte und in Nahrmedien verschiedener Kohlenhydratzusammensetzung ermittelt. Unter den multifaktoriellen Experimentalbedingungen kann dichte- und frequenzabhangige Selektion fur bestimmte Genotypen des AMY-Locus beobachtet werden. Die Genotypenfrequenzen und die Kohlenhydratzusammensetzung haben einen signifikanten Effekt auf die Viabilitat der AMY-Genotypen. Es treten auch signifikante intergenotypische Unterschiede auf, besonders bei den hohen Dichten. Die Heterozygoten S/F-Genotypen haben im allgemeinen eine niedrigere Viabilitat, die mit deren zunehmender Frequenz unter allen Bedingungen, d.h. in allen Medien und bei niedrigen und hohen Dichten, abnimmt. Die Ergebnisse weisen auf einen hohen Grad von Komplexitat und auch auf eine Wechselwirkung zwischen den beiden Arten der balancierenden Selektion hin.

Biochemical properties of enzyme alpha-amylase were surveyed in Drosophila obscura Old world group of species (D. subobscura, D. ambigua, D. obscura and D. tristis) sampled in the same habitat, with the aim to reveal some ecological and evolutionary aspects of amylase polymorphism, which has been studied extensively in D. subobscura, but not compared with other species in the group. The data obtained show that D. subobscura is distinct from the other three species regarding all biochemical amylase properties. Such a divergence also correlates with the niche breadth and relative abundance of these species in the same habitat.

As an ecological factor, a magnetic field can affect insects causing a wide range of responses. The main purpose of this study was to analyze the fitness components (postembryonic development and viability of individuals) and the antioxidant defense (superoxide dismutase, catalase, and total glutathione) in laboratory strains of Drosophila subobscura, originating from oak and beech forests after exposure to the strong static magnet (2.4 T, VINCY Cyclotron magnet). The first instar larvae were placed near the north pole (N group) or the south pole (S group) of the magnet for 2 h. Oak and beech populations of D. subobscura had longer development time and lower viability in N and S groups compared to controls. These differences were significant only in S group of oak population and in N group of beech population. Total glutathione content was significantly decreased in both exposed groups of oak population, while catalase activity was significantly increased in both exposed groups of beech population. Being significantly decreased in both exposed groups of oak population and significantly increased in S group of beech population in comparison to controls, superoxide dismutase activity was observed in different values. According to the results, it can be stated that applied static magnetic field could be considered a potential stressor influencing the fitness components and antioxidant defense in Drosophila flies.

Purpose: Extremely low frequency (ELF) magnetic fields are essential ecological factors which may induce changes in many organisms. The aim of this study was to examine the effects in Drosophila subobscura exposed for 48 h to ELF magnetic field (50 Hz, 0.5 mT) at different developmental stages. Materials and methods: Egg-first instar larvae developmental stage of D. subobscura isofemale lines was exposed to ELF magnetic field, and fitness components (developmental time, developmental dynamics, viability and sex ratio) and locomotor activity of three-day-old males and females were monitored. Also, just eclosed D. subobscura isofemale adults were exposed to ELF magnetic field and their locomotor activity was monitored just after. Results: ELF magnetic field shortens developmental time, increases viability and does not affect sex ratio of D. subobscura. No matter which developmental stage is exposed, ELF magnetic field significantly decreases locomotor activity of adult flies, but after exposure of just eclosed adults observed change lasts longer. Conclusions: Applied ELF magnetic field modifies fitness components and locomotor activity of D. subobscura. Observed effects can be attributed to the influence of magnetic field on different stages of development where the hormonal and nervous systems play important role in the control of examined parameters. Ministry of Education, Science and Technological Development, Republic of Serbia {[}173012, 173027]

The surface modification of nanocrystalline TiO2 particles (45 angstrom) with salicylate-type ligands consisting of an extended aromatic ring system, specifically 3-hydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid and 3,7-dihydroxy-2-naphthoic acid, was found to alter the optical properties of nanoparticles in a similar way to salicylic acid. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and a reduction in the band gap upon the increase in the electron delocalization when including an additional ring. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of a salicylate-type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. From both absorption measurements in methanol/water = 90/10 solutions and steady-state quenching measurements of modifier fluorescence upon binding to TiO2 in aqueous solutions, stability constants in the order of 10(3) M-1 have been determined at pH 2 and pH 3. Fluorescence lifetime measurements, in the presence and absence of colloidal TiO2 nanoparticles, indicated that the fluorescence quenching process is primarily static quenching, thus proving the formation of a nonfluorescent CT complex. The binding structures were investigated by using FTIR spectroscopy. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain the vibrational frequencies of charge transfer complexes, and the calculated values were then compared with the experimental data. Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3531]

Surface modification of nanocrystalline TiO2 particles (45 angstrom) with catecholate-type ligands consisting of an extended aromatic ring system, i.e., 2,3-dihydroxynaphthalene and anthrarobin, was found to alter the optical properties of the nanoparticles in a similar way to modification with catechol. The formation of inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites and the reduction of the band gap upon the increase of the electron delocalization on the inclusion of additional rings. The binding structures were investigated by FTIR spectroscopy. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of catecholate type (binuclear bidentate binding-bridging) thus restoring the six-coordinated octahedral geometry of surface Ti atoms. From the Benesi-Hildebrand plot, stability constants in methanol/water = 90/10 solutions at pH 2 of the order 10(3) M-1 have been determined. Quantum chemical calculations on model systems using density functional theory (DFT) were performed to obtain vibrational frequencies of charge transfer complexes, and the calculated values were compared with the experimental data.

The effect of culinary-medicinal Royal Sun Agaricus (Agaricus brasiliensis) hot water extract on methyl methane sulfonate (MMS) induced mutagenicity/genotoxity in Drosophila melanogaster was studied using a quick and broadly applicable in vivo assay, i.e., the wing somatic mutation and recombination test. We used 2(nd) instar larvae, trans-heterozygous for the third chromosome recessive markers, i.e., multiple wing hairs (mvh) and flare-3 [flr (3)], and fed them for 24 h with the aqueous extract of A. brasiliensis. For antigenotoxicity studies a 24-h pretreatment with the extract was done, followed by a 48-h treatment of the then 3(rd) instar larvae with MMS. The frequency of mutations of the wing blade changes (i.e., of the number of wing spots of different sizes) induced in somatic cells was determined as a parameter of genetic changes of the wing imaginal discs. The results showed that A. brasiliensis extract did not cause any genotoxic or mutagenic effects. No antigenotoxic and/or protective effect against the induction of mutations by MMS was observed. Instead, a possible enhanced mitotic recombination frequency by MMS was seen after pretreatment of the larvae with A. brasiliensis extract. Possible mechanisms of action are discussed. Ministry of Education and Science of the Republic of Serbia [173012, 173032]

We analyzed the developmental time, egg-to-adult viability, and developmental stability (fluctuating wing size asymmetry) in Drosophila subobscura, maintained for six generations on different concentrations of lead. Development time is significantly affected by generation and lead concentration, but interaction of these factors is not a significant source of variability for this fitness component. Generation and the interaction generation × concentration of lead significantly affect egg-to-adult viability. Levene’s test of heterogeneity of variance showed that variability of FA is not significant in any of the samples. Within both lead concentrations females showed significantly higher FA indices for the wing width than males. Within sexes, a significantly higher FA was found only in females for wing width FA between the control and the lower concentration of lead. The results show that if strong relationship between FA and the studied fitness components exists, it results in a stronger selection of unstable genotypes under lead as a stress factor and, consequently, FA needs to be used with caution as a biomarker in natural populations under environmental stress.

We analyzed changes in the genetic structure and effective population size of two ecologically distinct populations of Drosophila subobscura over several years. Population sizes of D. subobscura in beech and oak wood habitats for a period of 6 years were estimated by the capture-mark-release-recapture method. Inversion polymorphism parameters were also assessed in the same populations for a period of 3 years. Significant differences in the numbers of individuals were observed between sexes. This affected the effective population sizes between particular years. The ratio of the effective size over the cenzus dropped significantly in beech wood in 2 years. Although overall heterozygosity remained unchanged during the years in both habitats, frequencies of gene arrangements on five chromosomes show variability. After the bottleneck, some complex chromosomal arrangements appeared for the first time in both populations. Standard gene arrangements of chromosome A increased in frequency over the years in each habitat, while the complex arrangements remain rather stable and specific for each population. The results obtained indicate that the population structure may significantly change if the effective size of D. subobscura population is reduced, which is mostly related to microclimatic changes in habitats. Based on the results to date, monitoring of microevolutionary changes by using D. subobscura and its relatives seems a promising way to study the effects of global climate changes.