347 research outputs found

    Examining Mental Health and Well-being Provision in Schools in Europe: Methodological Approach

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    Schools are considered an ideal setting for community-based mental health and well-being interventions for young people. However, in spite of extensive literature examining the effectiveness of such interventions, very few studies have investigated existing mental health and well-being provision in schools. The current study aims to extend such previous research by surveying primary and secondary schools to investigate the nature of available provision in nine European countries (Germany, Ireland, the Netherlands, Poland, Serbia, Spain, Sweden, the UK and Ukraine). Furthermore, the study aims to investigate potential barriers to mental health and well-being provision and compare provision within and between countries

    Hybrid III-V/Si distributed-feedback laser based on adhesive bonding

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    A hybrid evanescently coupled III-V/silicon distributed-feedback laser with an integrated monitor photodiode, based on adhesive divinyl siloxane-benzocyclobutene bonding and emitting at 1310 nm, is presented. An output power of similar to 2.85 mW is obtained in a continuous wave regime at 10 degrees C. The threshold current is 20 mA and a sidemode suppression ratio of 45 dB is demonstrated. Optical feedback is provided via corrugations on top of the silicon rib waveguide, while a specially developed bonding procedure yields 40-nm-thick adhesive bonding layers, enabling efficient evanescent coupling

    The potential of different plant species for nickel accumulation

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    Contamination of the environment with toxic heavy metals is a mayor environmental problem. Aimed to find effective and economical attractive solutions for environment cleaning, scientists intensively evolve various phytoremediation techniques. Nickel is one of the essential micronutrients for plants, animals, and humans, but toxic at elevated concentrations. Also, it belongs to a group of heavy metals. In respect of the fact that Ni uptake relies upon plant species and that some of them show hyperaccumulation effects, the aim of our study was to analyse Ni concentration in certain plant species affected by Ni contamination of air and surface soil. Ni deposition in the air was below 60 mu g/m(2)/month, while Ni content in the soil was between 42 and 150 mu g/g. Average Ni content in plants ranged from 0. 1 to 5. 0 mu g/g. Regardless the analysed locality, the highest Ni (7.1 mu g/g) was obtained with the hogweed, whereas the lowest (4.5 mu g/g) with the vines. Ambrosia artemis folia and Taraxum officinale accumulated the greatest amounts of Ni (10. 72 and 10. 61 mu g/g, respectively). It may be concluded that the analysed plant species exhibit various phytoremediation potential for Ni under the same ecological conditions

    Cretaceous-Paleogene boundary (KPB) Fish Clay at Højerup (Stevns Klint, Denmark): Ni, Co, and Zn of the black marl

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    The black marl of the Fish Clay at Højerup is mainly made up of biogenic calcite and cheto-Mg-smectite. We suggest that the formation of the smectite occurred during the latest Maastrichtian (or earlier) and that it represents a short period of rapid redeposition through coastal erosion occurring at the Cretaceous-Paleogene boundary (KPB) sea level lowstand. The smectite of the black marl shows enhanced concentrations of Ni, Co, and Zn. The predominant source of these metals was probably the impact-ejecta fallout deposited on the top of nearby soil which was leached by the impact-induced-acidic surface waters. Most of the content of Ni and Co in the smectite is derived from the chondritic component of the fallout, but the ultimate origin of Zn may have been the impact-target rocks. Incorporation of the metals into the smectite took place during the KPB but before its redeposition at the Fish Clay site. The biogenic calcite-rich fraction of the black marl also shows high concentrations of Ni, Co, and Zn. The ultimate source of the metals was also probably the impact-ejecta fallout on the nearby soil at Stevns Klint. Enrichments of Ni in the biogenic calcite-rich/smectite fractions of the black marl represent the sudden input of the metal into the seawater at the KPB

    Isolation and characterization of bioactive secondary metabolites from selected Streptomyces strains

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    Actinomycetes are Gram-positive soil bacteria known as producers of secondary bioactive metabolites. In the search for new bioactive compounds collection of actinomycetes from the Laboratory for Microbial Molecular Genetics and Ecology (Institute of Molecular Genetic and Genetic Engineering, University of Belgrade) was screened according to several criteria - bioactivity, the presence of the genes for polyketide synthase (PKS), pigmentation, and crude culture extracts absorption profile in ultraviolet and visible (UV/Vis) spectra. Based on these we have isolated three strains NP10, JS520, and Streptomyces durmitotensis, previously renewed for didehydroroflamicoin (DDHR) production. Isolates NP10 and JS520 were identified to belong to the genus Streptomyces. Streptomyces sp. NP10 accumulated branched chain fatty acids, predominately isopalmitic, and cyclic dipeptides consisting of proline in combination with valine, isoleucine or alanine, that have a stimulating effect on the trophoblast cell line in culture at low concentrations (1 ng/ml and 1 mg/ml) and cytotoxic effect at high concentrations (1 mg/ml). Streptomyces sp. JS520 was determined to be exceptionally good producer of pigment undecylprodigiosine (UP) with antibacterial, antifungal, antioxidant and UV protective activities showing cytotoxic effects on trophoblast cell line in culture at high concentrations (1 ng/ml). Cytotoxicity of polyene macrolide antibiotic DDHR from S. durmitotensis was confirmed and it’s antifungal effects were shown. PKS cluster responsible for DDHR synthesis was subcloned in the cosmid library and partially sequenced. Optimization of culture conditions resulted in 2.12 times increased production of UP, and 1.1 times increased production of DDHR.Actinomycetes are Gram-positive soil bacteria known as producers of secondary bioactive metabolites. In the search for new bioactive compounds collection of actinomycetes from the Laboratory for Microbial Molecular Genetics and Ecology (Institute of Molecular Genetic and Genetic Engineering, University of Belgrade) was screened according to several criteria - bioactivity, the presence of the genes for polyketide synthase (PKS), pigmentation, and crude culture extracts absorption profile in ultraviolet and visible (UV/Vis) spectra. Based on these we have isolated three strains NP10, JS520, and Streptomyces durmitotensis, previously renewed for didehydroroflamicoin (DDHR) production. Isolates NP10 and JS520 were identified to belong to the genus Streptomyces. Streptomyces sp. NP10 accumulated branched chain fatty acids, predominately isopalmitic, and cyclic dipeptides consisting of proline in combination with valine, isoleucine or alanine, that have a stimulating effect on the trophoblast cell line in culture at low concentrations (1 ng/ml and 1 mg/ml) and cytotoxic effect at high concentrations (1 mg/ml). Streptomyces sp. JS520 was determined to be exceptionally good producer of pigment undecylprodigiosine (UP) with antibacterial, antifungal, antioxidant and UV protective activities showing cytotoxic effects on trophoblast cell line in culture at high concentrations (1 ng/ml). Cytotoxicity of polyene macrolide antibiotic DDHR from S. durmitotensis was confirmed and it’s antifungal effects were shown. PKS cluster responsible for DDHR synthesis was subcloned in the cosmid library and partially sequenced. Optimization of culture conditions resulted in 2.12 times increased production of UP, and 1.1 times increased production of DDHR

    Electrochemical properties of some gold(III) complexes with (S,S)-R(2)edda-type ligands

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    Oxidation-reduction properties of eleven gold(III) complexes with (S,S)-R(2)edda-type ligands was studied by cyclic and differential pulse voltammetry in DMSO. Series I: [AuCl2{(S,S)-R(2)eddip}]PF6, (S,S)-eddip = (S,S)-ethylenediamine-N,N'-di-2-propanoate, R = n-butyl, n-pentyl, isobutyl, isoamyl, cyclopentyl, 1-5; II: [AuCl2{(S,S)-R(2)eddch}]PF6, (S,S)-eddch = (S,S)-ethylenediamine-N,N'-di-2-(3-cyclohexyl)propanoate, R = methyl, ethyl, n-propyl, n-butyl, isobutyl, isoamyl, 6-11. Voltammograms in DMSO showed two successive irreversible reduction steps, where Au-I species were the final reduction product. Reduction potential values are in range from 116 to 156 mV (Ep(1)) and -520 to -572 mV (Ep(2)) for Series I and from 148 to 228 mV (Ep(1)) and -569 to -638 mV (Ep(2)) for Series II. In general, slightly easier reduction of complexes belonging to Series I (higher cytotoxicity) could be due to less steric hindrance around the gold center. Reduction potentials and anticancer activity are not in correlation

    The biological activities of roots and aerial parts of Alchemilla vulgaris L

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    The phytochemical composition, in vitro antioxidant and antimicrobial activities, cytotoxicity and antigenotoxicity of fruit extracts of Opuntia dillenii were studied. The phytochemical composition was evaluated using HPLC, GC-MS and UV–Vis spectrophotometry. Spectrophotometrical methods were used to estimate the antioxidant potential. Antimicrobial activity was determined using a microdilution method. The cytotoxic effects of the extracts were evaluated using the MTT assay. In vitro DNA-protective activity against hydroxyl radicalinduced DNA damage was also determined. The results showed that polar extracts of O. dillenii had a significant amount of phenolic compounds, including flavonoids, whereas non-polar extracts had mostly terpenoids and fatty acid derivatives. Moreover, several extracts showed good antioxidant and antimicrobial activities, with low cytotoxicity and significant DNA-protective effects. These results showed that the extracts of O. dillenii have promising bioactivity and further studies on the potential application in different areas of food and health might be beneficial

    Analiza primenjenih biosigurnosnih mera u proizvodnji sperme nerastova

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    This paper gives a detailed analysis of the applied biosecurity measures in the production of boar sperm at a swine reproduction center. Biosecurity indicators (existence of a written biosecurity plan, isolation, introduction of newly acquired animals into the herd, herd health, assessment of the personnel attitude towards equipment, traffic control, attitude towards visitors, feeding and watering control, manure management, disposal of dead animal carcasses, attitude towards other animals, rodents and birds control, sanitation) were viewed and evaluated by rating scale: (5) - excellent, (4) - very good, (3) - good, (2) - sufficient, (1) - insufficient, there are resources for improvement (0) - insufficient, with no resources for improvement. Obtained data were analyzed in the SWOT process, taking into account all the strengths, weaknesses, threats and opportunities for improving the biosecurity level. The situation in the center is rated as very good, with an average rating of 4.15. However, one disadvantage is serious and related to the boar facilities isolation possibilities, taking into account their location and the presence of two types of male breeding animals (boars and bulls) in the same location. Newly acquired breeding animals are purchased from various sources, but with a rigorous regime of control and not at the same time.U radu je detaljno analizirana primena biosigurnosnih mera u proizvodnji sperme nerastova u jednom centru za veštačko osemenjavanje svinja. Sagledani su i procenjeni svi indikatori biosigurnosti (postojanje pisanog plana biosigurnosti, izolacija, uvođenje novonabavljenih životinja u zapat, zdravstveni status zapata, ocena odnosa osoblja prema opremi, kontrola kretanja i prometa, odnos prema posetiocima, kontrola ishrane i vodosnabdevanja, izđubravanje, uklanjanje leševa uginulih životinja, odnos prema drugim životinjama na farmi, kontrola populacija glodara i ptica, sanitacija), i ocenjeni prema skali ocena: (5) - odličan, (4) - vrlo dobar, (3) - dobar, (2) - dovoljan, (1) - nedovoljan, ima resursa za poboljšanje, (0) nedovoljan, nema resursa za poboljšanje. U razmatranju rezultata primenjena je SWOT analiza i utvrđene prednosti, nedostaci, rizici i mogućnosti za podizanje nivoa biosigurnosti. Stanje u centru je ocenjeno kao vrlo dobro, uz prosečnu ocenu 4,15. Međutim, jedan nedostatak je veoma ozbiljan i odnosi se na mogućnost izolacije objekata, uzimajući u obzir njegovu lokaciju i prisustvo dve vrste muških priplodnih životinja (nerastova i bikova) na istoj lokaciji. Nove priplodne životinje se nabavljaju iz različitih izvora, ali uz rigorozan režim kontrole i ne u isto vreme. Svakako, izmeštanje objekata za držanje priplodnih nerastova na drugu bezbednu lokaciju predstavlja složen ali prioritetan zadatak, kojim bi se otklonile brojne pretnje po proizvodnju sperme

    Concentrations of manganese and iron in some woody and herbs plants

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    Heavy metals are the substances that indicate environmental pollution. The plants polluted with heavy metals may endanger natural environment and cause health problems in humans. In our multidisciplinary research of the concentrations of pollutants in forest ecosystems and natural environment in Belgrade, we examined the contents of heavy metals essential for plants but harmful in greater concentrations on a long-term basis. The fact that heavy metals manganese and iron are accumulated in plants to the greatest extent focused our work on determination of the level of concentrations of Mn and Fe in the vegetative parts of 8 plant types on three locations on the Avala Mountain and one location in the centre of the city of Belgrade. The analyses of heavy metals contents in plants were performed by the method of flame atomic absorption spectrophotometry. The examination of the existence of important differences between the average values was performed by implementation of Duncan’s test for the level of significance of 95%. The current contents of heavy metals in plants in the area of the protected natural resource Avala do not represent danger that would presently cause notable damage to forests but show the tendency of the increase of concentrations. Therefore, this issue should be constantly monitored
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