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  • Open Access English
    Authors: 
    Ana Camanho; Dovile Stumbriene; Flávia Barbosa; Audrone Jakaitiene;
    Country: Lithuania

    The Strategic Framework for European Cooperation in Education and Training (ET 2020) aimed to promote the exchange of best practices among the Member States. This paper assesses the performance evolution of European countries in terms of the common objectives for the education sector. The framework used to evaluate European education systems is based on constructing a composite indicator adopting a “benefit-of-the-doubt” approach. The evaluation of performance change over time is done using a Global Malmquist Index. Sigma and beta convergence of EU countries are also explored using non-parametric frontier techniques. The results are analysed for the period 2009–2018 and discussed in light of the goals envisaged and the national policies adopted. The results revealed a trend of improvement in the performance of education systems in most European countries in the period analysed. Although most European countries moved closer to the European best practice frontier over time, as confirmed by the values of sigma-convergence, a few countries are still lagging considerably below their peers, as revealed by the existence of divergence in beta.

  • Open Access
    Authors: 
    Adam Antosiak; Sigitas Šulčius; Przemysław Malec; Nada Tokodi; Antonia Łobodzińska; Dariusz Dziga;
    Publisher: Elsevier BV
    Countries: Lithuania, Poland

    Cyanobacteria play a significant role in ecosystem functioning as photosynthetic and CO2 fixing microorganisms. Whether and to what extent cyanophages alter these carbon and energy cycles in their cyanobacterial hosts is still poorly understood. In this study, we investigated changes in photosynthetic activity (PSII), expression of genes associated with the light phase of photosynthesis (psbA, petA, ndhK) and carbon metabolism (rbcL, zwf) as well as intracellular ATP and NADHP concentrations in freshwater bloom-forming filamentous cyanobacterium Aphanizomenon flos-aquae infected by cyanophage vB_AphaS-CL131. We found that PSII activity and expression level of rbcL genes, indicating potential for CO2 fixation, had decreased in response to cyanophage adsorption and DNA injection. During the period of viral DNA replication and assembly, PSII performance and gene expression remained at this decreased level and did not change significantly, indicating lack of transcriptional shutdown by the cyanophage. Combined, these observations suggest that although there is little to no interference between cyanophage DNA replication, host transcription and cellular metabolism, A. flos-aquae underwent a physiological state-shift toward lower efficiency of carbon and energy cycling. This further suggest potential cascading effect for co-occurring non-infected members of the microbial community.

  • Open Access
    Authors: 
    H. Morhun; D. Copilas-Ciocianu; T. Rewicz; M. O. Son; A. Khomenko; M. Huseynov; S. Utevsky; M. Grabowski;
    Publisher: Informa UK Limited
    Country: Lithuania

    The Ponto-Caspian amphipod Dikerogammarus bispinosus was originally described from the Black Sea basin. Its recent discovery in the Caspian Sea basin was puzzling because it was unknown whether it was an invasive or an overlooked native species in this area. Here, we examined specimens collected from both the Black and Caspian Sea basins by means of molecular species delimitation based on nuclear (28S) and mitochondrial (COI) DNA sequences, as well as scanning electron microscopy (SEM). Our analyses reveal that D. bispinosus comprises three evolutionary independent lineages that are molecularly and morphologically distinct. One lineage occurs throughout rivers in the Black Sea basin, while the other two inhabit the Caspian Sea and were found in sympatry, further reinforcing that they are distinct species. Our time-calibrated phylogeny indicates that these lineages split during the Late Miocene-Pliocene, a period corresponding with the separation of the Black and Caspian basins via the Caucasus mountain uplift. SEM imaging revealed morphological differences with respect to setal patterns on the gnathopod propodi among all three lineages. Therefore, our results clearly indicate not only that D. bispinosus is native in the Caspian region, but that it has been overlooked for a long time. Additional populations covering the entire range of this species complex need to be further studied in order to gain a more complete picture of its evolutionary history and resolve its taxonomy.

  • Open Access English
    Authors: 
    Rytis Maskeliunas; Robertas Damaševičius; Tomas Krilavičius; Modupe Odusami;
    Country: Lithuania

    We have studied the manuscript of Nicholas et al. [1] very attentively; here are our comments: The authors have used a different dataset (ADNI-3, rather than ADNI-2 used in [2]). The protocols of ADNI-2 and ADNI-3 datasets are not fully consistent [3]. The ADNI MR data set includes a wide range of scanner platforms; however, there has been a broad gap between older MRI systems and the state-of-the-art systems within each vendor’s product line. In ADNI-3, the “ADNI 3 Basic” and “ADNI 3 Advanced” protocols were used. The authors failed to mention if the images they used were made using a protocol compatible with ADNI-2. The dMRI spatial resolution was improved between ADNI-2 and ADNI-3 by reducing the voxel size from 2.7 x 2.7 x 2.7 mm to 2.0 x 2.0 x 2.0 mm [4]. This may have influenced the results. Moreover, the classification results among these studies are not directly comparable, because they differ in terms of the sets of participants. We fully agree that the replication of important findings by multiple independent investigators is fundamental to the accumulation of scientific evidence [5]. Deep learning network models are notoriously known for being difficult to replicate, even if the same sets of parameters are used. The training of neural network models is not deterministic, so the models are likely to produce differing results [6]. The strive of the authors to precisely replicate the results may not be achievable. [...]

  • Publication . Other literature type . Article . 2022
    Open Access English
    Authors: 
    A Grišinas;
    Country: Lithuania

    This article suggests that in times of digital mass media, mediatized political issues create a self-perpetuating phenomenon that is here titled a neo-myth. Through combining interdisciplinary theories of Issue-Attention Cycles and Social Dramas, the article argues that the standardized ways that political issues are framed, mass-mediated and consumed in a contemporary society, paradoxically create a cyclical and self-perpetuating pattern. Instead of being linear, rational and cause-to-solution oriented, they become stereotypical, cyclical and performative, thus resembling mythological patterns both content and form-wise. The article discusses how and why these neo-myths form, as well as how political, public and media actors interact within the process. It discusses them in terms of their emergence, structure, causality, processual logics and formal variety, and suggests that the phenomenon falls in line with the findings of recent research on the shifting knowledge patterns in times of digital culture.

  • Open Access
    Authors: 
    Md. Reazuddin Repon; Halima Tus Sadia; Tarikul Islam; Mohammed M. Rahman; Md. Rezaul Karim;
    Publisher: Elsevier BV
    Country: Lithuania

    Applying flame retardant finish on jute makes flame protective jute products that can be another diversified use of it. The target of this experiment is to observe the flame retardancy improvement of the fabric properties after finishing treatment with various flame retardant chemicals. The untreated (raw) and H2O2 bleached jute fabrics having plain weave were used in this experiment. Borax, diammonium phosphate (DAP) and thiourea were used as flame retardant chemicals. The combinations of these chemicals were applied to the fabrics by the pad-dry-cure method with various concentrations. Vertical flammability, breaking load percentage, and weight gain percentage were performed on all samples to observe the change in fabric properties. Significant improvement was found for all chemical combinations compared to untreated fabrics. Here, the flame spread time and weight gain percentage increase, but the breaking load percentage decreases for every combination. Among all combinations, the borax and DAP combination especially at 6% concentration shows the 305% improvement of flame spread time for raw jute and 276% for bleached jute fabric. In contrast, the borax and thiourea combination showed the progress of weight gain percentage. Besides, better wash durability was reported for all samples after five washing cycles. These flame-retardant jute fabrics have prospective industrial applications as brattice cloth in mines and many other potential fields of applications such as flame-retardant kitchen aprons, furnishings for a public hall, theater and hospitals.

  • Open Access
    Authors: 
    Česnakas, Giedrius;
    Publisher: Vilnius University Press
    Country: Lithuania

    Kolektyvinė politinė vaizduotė apibrėžia pasaulio tvarką lemiančias politinių bendruomenių sąveikas. Santykinė Vakarų valstybių galia leido įtvirtinti pirmąją globalią pasaulio tvarką, kuri yra žinoma kaip vestfalinė pasaulio tvarka. Vis dėlto didėjanti santykinė Kinijos Liaudies Respublikos galia leidžia siūlyti alternatyvią pasaulio tvarkos viziją, kuri yra paremta jos politine vaizduote. Zhao Tingyango intelektualiai atgaivinta hierarchinė Tianxia („Paskliautės“) tvarka potencialiai gali mesti iššūkį vestfalinei tvarkai. Straipsnyje analizuojama, ar, atsižvelgiant į šiandieninę globalią politinę aplinką, Tianxia tvarka potencialiai gali pakeisti vestfalinę tvarką? Diskusija plėtojama remiantis Jeffrey Legro kolektyvinių idėjų poveikio užsienio politikos pokyčiams modeliu – jis pritaikomas pasaulio tvarkos pokyčių analizei. Straipsnio išvados rodo, kad Tianxia turi labai ribotas galimybes pakeisti vestfalinę pasaulio tvarką, nes jos ortodoksija išlieka stipri. Vestfalinė tvarka geba adaptuotis besikeičiančioje aplinkoje ir yra pajėgi integruoti hierarchinius elementus. Nepaisant Kinijos Liaudies Respublikos santykinės galios augimo ir didėjančių galimybių formuoti normas, kurios sulaukia Kinijos Liaudies Respublikos visuomenės palaikymo, tęstinumas dažniausiai vyrauja pokyčio atžvilgiu, todėl ir suverenitetas, būdamas tvarkos įpročiu, vyrauja prieš hierarchinę tvarką. Galiausiai, straipsnyje teigiama, kad Tianxia tvarka nėra atspari anarchiniam-konkurenciniam žmogaus prigimties veiksniui. The collective political imagination establishes world orders that define how political communities interact. The relative power of the West allowed the introduction of the first global world order, known as the Westphalian. However, the increasing relative power of the People’s Republic of China allows it to promote an alternative world order vision, which is the result of its political imagination. Zhao Tingyang’s re-imagined hierarchic Tianxia order is seen as a challenger to the Westphalian order. This paper analyzes whether the Tianxia order can replace the Westphalian, considering the contemporary global political environment. The discussion is based on Jeffrey Legro’s theory of collective ideas and foreign policy change, applying it to world order replacement analysis. The findings suggest that the Tianxia has significant limitations in replacing the Westphalian world order. The Westphalian order orthodoxy remains strong. The order is also adaptable, capable of including hierarchical elements. Despite the increase of the PRC’s relative power and its greater capabilities to shape norms with domestic support, continuity usually prevails, so the habit of sovereignty prevails over hierarchical order. Finally, the article argues that the Tianxia order is not resilient to the anarchic-competitive element of human nature.

  • Publication . Other literature type . Article . 2022
    Open Access
    Authors: 
    Peckus, Domantas; Tamulevičienė, Asta; Mougin, Karine; Spangenberg, Arnaud; Vidal, Loic; Bauerlin, Quentin; Keller, Marc; Henzie, Joel; Puodžiukynas, Linas; Tamulevičius, Tomas; +1 more
    Publisher: Optica Publishing Group
    Country: Lithuania

    The aim of shape-controlled colloidal synthesis of gold (Au) is to produce Au nanoparticles (NPs) with fine control of shapes, sizes, and dispersities. We show how transient absorption spectroscopy (TAS) can be used to rapidly and accurately quantify the vast ensemble of shapes of Au NPs in solution within minutes, including the synthesized nanorods, decahedra, and nanospheres. Colloidal solutions containing Au NPs were measured in TAS and their localized surface plasmon resonance (LSPR) modes were classified according to the shape, wavelength and number of peaks. Then their excited-state relaxation dynamics were used to ascertain their electron-phonon (e-ph) coupling time constant and frequency of optomechanical modes. TAS can quickly show that an Au nanosphere sample contains a tiny fraction of Au nanorods, whereas steady-state absorbance is totally blind to the presence of nanorods. Additionally, the TAS experiments indicate that the characteristic e-ph coupling time constants in Au nanorods depend on the NPs dimensions at high excitation intensity (> 6 µJ/cm2) which can help identify if there are any elongated Au NPs in Au spheres samples. Finally, optomechanical oscillations formed by NPs breathing modes were observed, providing information related to the average size and monodispersity of Au nanospheres and nanorods.

  • Open Access
    Authors: 
    Manhanga, Fallon Clare; Rudžionis, Žymantas; Ivanauskas, Ernestas; Augonis, Algirdas;
    Publisher: EDP Sciences
    Country: Lithuania

    The concept of self-healing concrete is becoming more necessary as sustainability in construction is more desirable. Amongst the current solutions in this technology are autogenous, chemical, and bacterial self-healing. It is paramount that secondary raw materials be used in the production of selfhealing concrete as a form of a sustainable solution. Therefore, in this paper, the admixture “Betocrete-CP-360-WP”, which is a crystallizing waterproofing admixture with hydrophobic effect and is 100% recyclable, has been used and its effect on the physical, chemical, and mechanical properties of concrete, as well as selfhealing capabilities of concrete, have been determined. According to the obtained results, the crystalline additive “Betocrete-CP-360-WP” has no effect on density and slightly increases the amount of entrained air in the concrete mix. However, it does decrease the workability of the concrete mixture which could prove problematic in transportation to the construction site or in concreting in general. Also, with the crystalline admixture in the concrete mix, a 60% reduction in concrete compressive strength after one day of hardening has been estimated, but after 7 and 28 days, the strength attained is within the ranges of the control samples. In addition, concrete containing Betocrete-CP360-WP was 30% less water permeable as compared to control samples. The self-healing efficiency of the concrete was determined by a water flow test through a formed crack (approximately 0.35 mm wide). This was done by gluing a plastic pipe to the top of the cracked concrete specimens and maintaining a constant pressure of the water in the pipe. The experiment was continued for 28 days, and the crack self-healing efficiency of the concrete was calculated from the differences in the amount of water passed through the crack before healing and after 7, 14, 21 and 28 days of the healing process. After 28 days of the water flow test, the cracks in the concrete with the crystalline admixture and recycled concrete dust were completely healed, while the control specimens were not.

  • Open Access English
    Authors: 
    Jana Bürger; Filip Küzmič; Urban Šilc; Florian Jansen; Erwin Bergmeier; Milan Chytrý; Alicia Cirujeda; Silvia Fogliatto; Guillaume Fried; Denise F. Dostatny; +16 more
    Countries: Spain, United Kingdom, Lithuania, United Kingdom, Lithuania

    Questions Two scientific disciplines, vegetation science and weed science, study arable weed vegetation, which has seen a strong diversity decrease in Europe over the last decades. We compared two collections of plot-based vegetation records originating from these two disciplines. The aim was to check the suitability of the collections for joint analysis and for addressing research questions from the opposing domains. We asked: are these collections complementary? If so, how can they be used for joint analysis? Location Europe. Methods We compared 13 311 phytosociological relevés and 13 328 records from weed science, concerning both data collection properties and the recorded species richness. To deal with bias in the data, we also analysed different subsets (i.e., crops, geographical regions, organic vs conventional fields, center vs edge plots). Results Records from vegetation science have an average species number of 19.0 ± 10.4. Metadata on survey methodology or agronomic practices are rare in this collection. Records from weed science have an average species number of 8.5 ± 6.4. They are accompanied by extensive methodological information. Vegetation science records and the weed science records taken at field edges or from organic fields have similar species numbers. The collections cover different parts of Europe but the results are consistent in six geographical subsets and the overall data set. The difference in species numbers may be caused by differences in methodology between the disciplines, i.e., plot positioning within fields, plot sizes, or survey timing. Conclusion This comparison of arable weed data that were originally sampled with a different purpose represents a new effort in connecting research between vegetation scientists and weed scientists. Both collections show different aspects of weed vegetation, which means the joint use of the data is valuable as it can contribute to a more complete picture of weed species diversity in European arable landscapes. Published

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