13 research outputs found

    FURTHER RANGE EXPANSION OF THE SCULPTURED RESIN BEE (MEGACHILE SCULPTURALIS) IN SERBIA AND BOSNIA & HERZEGOVINA

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    Megachile sculpturalis is the first non-native bee species established in Europe, originating from E-Asia. Since early detections in SW-Europe (2008–2010) its spreading resulted in a range currently spanning nearly 2,800 km x 1,100 km across the southern and central Europe. In SE-Europe establishment was confirmed since 2015 in NE-Hungary, followed by detection in N-Serbia (2017), and wider spreading across the eastern Pannonian Plain (2018–2019); eventually it was detected in NW-Bosnia & Herzegovina (2020). Accordingly, the repeated calls for monitoring of M. sculpturalis spread were voiced, aiming to address its potential invasiveness, but mostly lacking a more specific assessment protocol. A 'working concept' for a comprehensive monitoring of M. sculpturalis was proposed within the survey conducted in Belgrade (Serbia) during 2017–2019, based on quantitative assessment of bee population trends in relation to focal plant resources. There was a need to improve and broaden this initial framework, e.g., to allow for different spatio-temporal scales and various potential usage requirements. Therefore, in 2020 we considerably extended the research scope, defined at two spatial scales: LOCAL, for the Belgrade area – the continuation of protocol development, through a high-intensity assessment of M. sculpturalis abundance, bionomics, and distribution, in parallel with assessment of extended set of relevant plants (and potential bee-plant interactions); REGIONAL, a survey covering the bee spreading across Serbia and Bosnia & Herzegovina, aiming to provide a reference time-section in expanding SE-European front, while also extending the knowledge of its environmental affinities. The study included the launching of a pioneering citizen science project, which enabled a remarkable geographic coverage despite modest return of positive reports. The Belgrade-scale survey yielded a modest increase in recorded locations, relative to 2019, but the recording efficiency was decreased, despite a much intensified surveying efforts and extended coverage. This corroborated the importance of inter-seasonal variation of key food resources, which affects both the population dynamics and detectability of this bee, through alternating concentration and dilution effects. We confirmed the strong association of detection success with availability and variability of blooming Styphnolobium, at both scales, indicating the highest relevance of inclusion of this plant into monitoring assessment protocols. The established phenological extent of M. sculpturalis activity (>70 days) also closely corresponded with the phenology of Styphnolobium blooming; yet it does not represent the entire phenological span for the region. Almost no record came from surveying other plants. The regional expansion of M. sculpturalis during 2017–2020 is documented from 19 wider locations (16 added in 2020). It is particularly well established in the Pannonian, and to a lesser extent in peri-Pannonian area of Serbia and B&H, while the approximated range extent was likely doubled during 2019–2020. Further south records were scarce, indicating the slower expansion across the hilly-mountainous part of the Balkans. Records largely came from urban or other settlements, only about a third from semi-natural or agricultural environments

    Monitoring of respiratory volumes by an long period grating sensor of bending

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    Here, we present a method of respiratory volumes monitoring using a single fiber-grating sensor of bending. Measurements are conducted using simple monochromatic interrogation scheme that relies on a photodiode measurement of the power transmitted through a long period grating (LPG) sensor at fixed wavelength. Good sensor accuracy in measurements of tidal and minute respiratory volumes for different types of breathing is achieved.Conference on Light in Nanoscience and Nanotechnology (LNN), Oct 20-22, 2015, Hissar, Bulgari

    Estimation of the Sensitivity of a Multi-Parameter Fiber Grating Sensor

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    In this paper, we use a powerful mathematical concept based on Fisher information (FI) to estimate the cross-sensitivity of multi-parameter sensors. FI has been used in various branches of natural and social sciences [1], in both classical and quantum systems [2]. Lately, it has been used for estimation of interferometer sensitivity in quantum optics [3], as well as in classical optical interferometers [4]. Here, we expand its application to fibre grating sensors that are sensitive to several environmental (temperature, humidity) and mechanical (strain, pressure, curvature) parameters simultaneously [5]. FI is a local probability measure of obtaining an unknown parameter θ from the data measured at the sensor output, X. In the theory of measurement, FI directly enters the relation which determines the lower bound of the measurement uncertainty known as Cramer-Rao bound (CRB = 1/ FI (θ ) ). The sensor sensitivity is optimized by maximization of the corresponding FI. In the case of a multi-parameter sensor, FI assumes a matrix form defined via the probability distribution function f(X| θ) of the measured variable X conditioned by θ, where both X and θ are vector quantities. ( ) ( ) i n j n f X FI E i j i j ; 1,2,... ; 1,2,..., 2 ln , = = ∂ ∂ ∂ = − θ θ θ θ . Here, we develop a comprehensive model of the spectral response of fibre gratings to changes in multiple parameters and apply Fisher's formalism to optimize their sensitivity in the realistic parameter space. We start from a 1-parameter model of a long-period grating sensor of curvature and corroborate our approach by comparison with the conventional sensitivity models and the experimental data. We then expand the model to describe a 2-parameter long-period grating sensor of curvature and temperature. Based on this analysis, we recommend the multi-parameter interrogation scheme (estimator) and optimize grating parameters to render the highest sensitivity.V International School and Conference on Photonics and COST actions: MP1204, BM1205 and MP1205 and the Second international workshop "Control of light and matter waves propagation and localization in photonic lattices" : PHOTONICA2015 : book of abstracts; August 24-28, 2015; Belgrad

    Pripravci na bazi lekovitog bilja koji se mogu koristiti u urbanoj poljoprivredi

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    The paper presents the possibilities of using different types of preparations prepared from certain types of medicinal plants, which can be used in plant nutrition and protection, as well as in the composting process for the needs of plant cultivation in urban agriculture. The trend of importance of urban agriculture, both in terms of food safety and innovative practices, is increasingly present in highly developed countries as well as developing countries. This type of agriculture can play an important role in justice and fairness in terms of food distribution, but also in improving air quality, biodiversity and ecosystem services. In this regard, the application of preparations based on medicinal plants introduces innovative methods of urban agriculture that can be considered a tool to ensure future food safety.U radu se prikazuju mogućnosti upotrebe različitih vrsta pripravaka pripremljenih od pojedinih vrsta lekovitog bilja, a koji se mogu primenjivati u ishrani i zaštiti bilja, kao i u procesu kompostiranja za potrebe gajenja bilja u urbanoj poljoprivredi. Trend značaja urbane poljoprivrede kako u pogledu bezbednosti hrane, tako i u inovativnim praksama je sve više prisutan kako u visokorazvijenim, tako i državama u razvoju. Ova vrsta poljoprivrede može igrati važnu ulogu u pravdi i pravičnosti u pogledu hrane, ali i unapređenju kvaliteta vazduha, biodiverziteta i eko-sistemskih usluga. S tim u vezi, primenom pripravaka na bazi lekovitog bilja uvode se inovativne metode urbane poljoprivrede koje se mogu smatrati alatom za osiguravanje buduće sigurnosti hrane

    Theoretical analysis of a Mach-Zehnder interferometer with a porous-film waveguide

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    Here we present a comprehensive theoretical study of a porous-film sensor of fluid in Mach-Zehnder configuration. It is found that the penetration of a fluid into the film pores causes amplitude and phase modulation of the interferometer output signal, maximizing the sensitivity at a certain value of the fluid refractive index. We define the Fisher information for this interferometer and show that it is a good measure of its sensitivity, hence suitable as an evaluation function in sensor optimization. We propose the sensor structure and design thin films that maximize its sensitivity to water, alcohol solutions and oils. The estimated sensitivity of the order of 10(-5) RIU to the fluid refractive index and of 5 pm to the changes in the film thickness indicate the potential of this sensor for applications in biomedicine, chemistry and environmental protection, and as a tool for the film characterization

    Early-phase colonisation by introduced sculptured resin bee (Hymenoptera, Megachilidae, Megachile sculpturalis) revealed by local floral resource variability

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    There is a growing interest to document and better understand patterns and processes involved in non-native bee introductions and subsequent colonisation of new areas worldwide. We studied the spread of the East Asian bee Megachile sculpturalis in Serbia and south-eastern Europe; the bee was earlier established in the USA (since 1994) and western Europe (since 2008). Its establishment in Serbia remained dubious throughout most of 2017–2019, following its first detection. We hereby report on its establishment and spreading, which were corroborated in 2019 under specific circumstances. Owing to an exceptionally poor blooming of Styphnolobium japonicum in 2019, we recorded a high activity density of M. sculpturalis concentrated on a scarce key food resource. We present a novel quantitative approach for an improved early detection of M. sculpturalis, based on the interplay between the bee local occurrence pattern and dynamics of key food-plant(s) availability. This approach seems particularly effective during the early-phase colonisation, at initially low population density of introduced bees. We address the importance of integration of the genuine plant usage patterns with context-specific bee assessment options in establishing effective monitoring. The improved understanding of M. sculpturalis local dynamics triggered the questions about possible origin(s) and modes of its dispersal east of the Alps. To explore the possible scenarios of M. sculpturalis introduction(s), we extended the study to a wider spatio-temporal context – the region of SE Europe (2015–2019). The two complementary study approaches (at local and regional scale) provided more comprehensive evidence of bee dispersal history and the detection patterns in varied recording contexts. Based on this two-scale approach, we suggest that a diffusive mode of M. sculpturalis introduction into Serbia now seems to be a more plausible scenario (than a long-distance jump). We argue that the integration of outcomes from the contrasting approaches (a systematic surveillance, based on plant resources and a broad-scale opportunistic recording) could be of great methodological relevance for the development of future monitoring protocols

    Evanescent-wave optical gas sensor with a porous thin-film coating

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    In this paper, we present the analysis and numerical model of absorptive gas detection by an optical evanescent-wave sensor. We investigate the influence of sensor geometry and thin-film porosity on the attenuation of guided modes caused by their interaction with the gas. We show that film porosity is a critical parameter that should be carefully optimized for a chosen mode. These findings served as a basis for the design of an experimentally realizable sensor of carbon dioxide.4th International School and Conference on Photonics, Aug 26-30, 2013, Belgrade, Serbi

    Wine or beer?

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    Wine and beer are nowadays the most popular alcoholic beverages, and the benefits of their moderate consumption have been extensively supported by the scientific community. The main source of wine and beer’s antioxidant behavior are the phenolic substances. Phenolic compounds in wine and beer also influence final product quality, in terms of color, flavor, fragrance, stability, and clarity. Change in the quantity and quality of phenolic compounds in wine and beer depends on many parameters, beginning with the used raw material, its place of origin, environmental growing conditions, and on all the applied technological processes and the storage of the final product. This review represents current knowledge of phenolic compounds, comparing qualitative and quantitative profiles in wine and beer, changes of these compounds through all phases of wine and beer production are discussed, as well as the possibilities for increasing their content. Analytical methods and their importance for phenolic compound determination have also been pointed out. The observed data showed wine as the beverage with a more potent biological activity, due to a higher content of phenolic compounds. However, both of them contain, partly similar and different, phenolic compounds, and recommendations have to consider the drinking pattern, consumed quantity, and individual preferences. Furthermore, novel technologies have been developing rapidly in order to improve the polyphenolic content and antioxidant activity of these two beverages, particularly in the brewing industry

    Agrotechnical aspect of using flower strips in agricultural production

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    Cvetni pojasevi predstavljaju jednu od mera IPARD III program za period 2021-2027. godine koju će Ministarstvo poljoprivrede, šumarstva i vodoprivrede Republike Srbije u narednom periodu sufinansirati. Cvetni pojasevi seju se uz ivicu parcele i služe kao staništa za oprašivače (polinatore), druge korisne insekte i ptice, doprinose poboljšanju biodiverziteta (biološke raznolikosti), zatim sprečavaju eroziju zemljišta i služe za unapređenje ruralnog ambijenta. U radu je dat prikaz pojedinih cvetnih vrsta koje najčešće koriste u smeši semena za cvetne pojaseve, kao i agrotehnički aspekt primene cvetnih pojaseva i njihova dobrobit za agroekosistem.Flower strips are one of the measures of the IPARD III program for the period 2021-2027. which will be co-financed by the Ministry of Agriculture, Forestry and Water Management of the Republic of Serbia. Flower strips are sown along the edge of the plot and serve as habitats for pollinators, other beneficial insects and birds, contribute to the improvement of biodiversity, then prevent soil erosion and serve to improve the rural environment. The paper presents the description of certain flower species that are most often used in the seed mixture for flower strips, as well as the agrotechnical aspect of the application of flower strips and their benefit for the agroecosystem

    The history written in the grapevine genome: The case of Montenegrin varieties

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    Trabajo presentado en el 1st International Conference on Vranac and other Montenegrin, celebrado en Podgorica (Montenegro), del 20 al 22 de noviembre de 2017Peer reviewe
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