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  1. Article ; Online: The sense of school belonging

    Stojanović Marija / Popović-Ćitić Branislava

    Nastava i Vaspitanje, Vol 71, Iss 3, Pp 403-

    Its importance for the positive development of students and prevention of behavioural problems

    2022  Volume 423

    Abstract: The sense of school belonging is defined as the extent to which students feel personally accepted, respected, included and supported by others in the school environment. Given that certain authors regard school belonging as the key factor in the adequate ...

    Abstract The sense of school belonging is defined as the extent to which students feel personally accepted, respected, included and supported by others in the school environment. Given that certain authors regard school belonging as the key factor in the adequate development of children and youth, this paper aims to summarize and present theoretical and research findings that testify to the importance of the sense of school belonging for students' positive development and prevention of behavioral problems. In addition, the basic tenets of prevention science and the positive development perspective are discussed, and the relationship between these two approaches is analyzed. The results of our review suggest that the sense of school belonging is related to a wide range of academic and developmental outcomes, such as academic achievement and motivation, school engagement, prosocial behavior, life satisfaction, self-esteem, positive identity, well-being, adaptive adjustment, etc. In other words, past research has indicated that, depending on the extent to which the sense of school belonging is developed, its effects can be interpreted within the context of risk and protective/promotion factors in students' mental health and behavioral problems. The above implies that actors in the education system must not lose sight of the importance of the sense of school belonging for students' reaching their full potential. Moreover, taking into account the striving of prevention science to identify and enhance the factors underpinning protective processes, further research is needed on the factors and mechanisms of development of the sense of school belonging.
    Keywords school belonging ; prevention science ; protective factors ; promotion factors ; students' behavioral problems ; Theory and practice of education ; LB5-3640
    Subject code 370
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher Pedagoško društvo Srbije i Institut za pedagogiju i andragogiju Filozofskog fakulteta Univerziteta u Beogradu
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Substituent Effect on Triplet State Aromaticity of Benzene.

    Baranac-Stojanović, Marija

    The Journal of organic chemistry

    2020  Volume 85, Issue 6, Page(s) 4289–4297

    Abstract: Density functional theory calculations have been performed to explore the substituent effect on benzene's structure and aromaticity upon excitation to the first triplet excited state ( ... ...

    Abstract Density functional theory calculations have been performed to explore the substituent effect on benzene's structure and aromaticity upon excitation to the first triplet excited state (T
    Language English
    Publishing date 2020-02-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.9b03472
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

    Zs.A 4473: Show issues Location:
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  3. Article ; Online: Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects.

    Baranac-Stojanović, Marija / Aleksić, Jovana / Stojanović, Milovan

    Organic & biomolecular chemistry

    2023  Volume 22, Issue 1, Page(s) 144–158

    Abstract: Computational investigation at the BHandHLYP/6-311+G(d,p) level of theory of the gas-phase tautomerism of 2- and 4-pyridones confirmed the slight prevalence of lactim in the case of the former, but its dominance in the case of the latter, as shown ... ...

    Abstract Computational investigation at the BHandHLYP/6-311+G(d,p) level of theory of the gas-phase tautomerism of 2- and 4-pyridones confirmed the slight prevalence of lactim in the case of the former, but its dominance in the case of the latter, as shown previously. Examination of aromaticity by using HOMA, EDDB, NBOdel, NICS and AICD led to the conclusion that tautomerization of 4-pyridone results in greater aromaticity gain. It is also driven by the Pauli repulsion relief, which was revealed by the tautomerization energy decomposition analysis. By contrast, in the case of 2-pyridone, lactim is favoured by orbital and electrostatic interactions and disfavoured by the Pauli repulsion. Aromaticity gain in this case is smaller. The position of the tautomeric equilibrium can be modulated by substituent inductive effects (Cl and F), inductive and resonance effects (NH
    Language English
    Publishing date 2023-12-20
    Publishing country England
    Document type Journal Article
    ZDB-ID 2097583-1
    ISSN 1477-0539 ; 1477-0520
    ISSN (online) 1477-0539
    ISSN 1477-0520
    DOI 10.1039/d3ob01588b
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Triplet-State Structures, Energies, and Antiaromaticity of BN Analogues of Benzene and Their Benzo-Fused Derivatives.

    Baranac-Stojanović, Marija

    The Journal of organic chemistry

    2019  Volume 84, Issue 21, Page(s) 13582–13594

    Abstract: It is well known that benzene is aromatic in the ground state (the Hückel's rule) and antiaromatic in the first triplet ( ... ...

    Abstract It is well known that benzene is aromatic in the ground state (the Hückel's rule) and antiaromatic in the first triplet (T
    Language English
    Publishing date 2019-09-30
    Publishing country United States
    Document type Journal Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.9b01858
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

    Zs.A 4473: Show issues Location:
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    Jg. 1995 - 2021: Lesesall (2.OG)
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  5. Article ; Online: A DFT Study of the Modulation of the Antiaromatic and Open-Shell Character of Dibenzo[a,f]pentalene by Employing Three Strategies: Additional Benzoannulation, BN/CC Isosterism, and Substitution.

    Baranac-Stojanović, Marija

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2019  Volume 25, Issue 41, Page(s) 9747–9757

    Abstract: Dibenzo[a,f]pentalene ([a,f]DBP) is a highly antiaromatic molecule having appreciable open-shell singlet character in its ground state. In this work, DFT calculations at the B3LYP/6-311+G(d,p) level of theory were performed to explore the efficiency of ... ...

    Abstract Dibenzo[a,f]pentalene ([a,f]DBP) is a highly antiaromatic molecule having appreciable open-shell singlet character in its ground state. In this work, DFT calculations at the B3LYP/6-311+G(d,p) level of theory were performed to explore the efficiency of three strategies, that is, BN/CC isosterism, substitution, and (di)benzoannulation of [a,f]DBP, in controlling its electronic state and (anti)aromaticity. To evaluate the type and extent of the latter, the harmonic oscillator model of aromaticity (HOMA) and aromatic fluctuation (FLU) indices were used, along with the nucleus-independent chemical shift NICS-XY-scan procedure. The results suggest that all three strategies could be employed to produce either the closed-shell system or open-shell species, which may be in the singlet or triplet ground state. Triplet states have been characterized as aromatic, which is in accordance with Baird's rule. All the singlet states were found to have weaker global paratropicity than [a,f]DBP. Additional (di)benzo fusion adds local aromatic subunit(s) and mainly retains the topology of the paratropic ring currents of the basic molecule. The substitution of two carbon atoms by the isoelectronic BN pair, or the introduction of substituents, results either in the same type and very similar topology of ring currents as in the parent compound, or leads to (anti)aromatic and nonaromatic subunits. The triplet states of all the examined compounds are also discussed.
    Language English
    Publishing date 2019-07-08
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1478547-X
    ISSN 1521-3765 ; 0947-6539
    ISSN (online) 1521-3765
    ISSN 0947-6539
    DOI 10.1002/chem.201901845
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  6. Article ; Online: Solid-state silica gel-catalyzed synthesis of fluorescent polysubstituted 1,4- and 1,2-dihydropyridines.

    Aleksić, Jovana / Stojanović, Milovan / Bošković, Jakša / Baranac-Stojanović, Marija

    Organic & biomolecular chemistry

    2023  Volume 21, Issue 6, Page(s) 1187–1205

    Abstract: We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating ...

    Abstract We present the green, highly atom-economical, solid-state silica gel-catalyzed synthesis of polysubstituted 1,4- and 1,2-dihydropyridines (DHPs) from commercially available materials, amines and ethyl propiolate. The DHP skeleton was assembled by heating the reactants and silica gel in a closed vessel. Aliphatic amines provided 1,4-isomers as the main or only DHP products, but the reactions of aromatic amines yielded a mixture of 1,4- and 1,2-isomers. To the best of our knowledge, this is the first example of the formation of a 1,2-DHP structure by the reaction of an amine with propiolic ester. Addition of 1 mass percent of H
    Language English
    Publishing date 2023-02-08
    Publishing country England
    Document type Journal Article
    ZDB-ID 2097583-1
    ISSN 1477-0539 ; 1477-0520
    ISSN (online) 1477-0539
    ISSN 1477-0520
    DOI 10.1039/d2ob02119f
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Revival of Hückel Aromatic (Poly)benzenoid Subunits in Triplet State Polycyclic Aromatic Hydrocarbons by Silicon Substitution.

    Baranac-Stojanović, Marija / Stojanović, Milovan / Aleksić, Jovana

    Chemistry, an Asian journal

    2022  Volume 17, Issue 4, Page(s) e202101261

    Abstract: By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly) ... ...

    Abstract By employing density functional theory (DFT) calculations we show that mono- and disilicon substitution in polycyclic aromatic hydrocarbons, having two to four benzene units, quenches their triplet state antiaromaticity by creating Hückel aromatic (poly)benzenoid subunit(s) and weakly antiaromatic, or almost nonaromatic silacycle. Therefore, such systems are predicted to be globally aromatic in both the ground state and the first excited triplet state. Putting the silicon atom(s) into various positions of a hydrocarbon provides an opportunity to tune the singlet-triplet energy gaps. They depend on the global aromaticity degree which, in turn, depends on the type of aromatic carbocyclic subunit(s) and the extent of their aromaticity. On the basis of the set of studied compounds, some preliminary rules on how to regulate the extent of global, semiglobal and local aromaticity are proposed. The results of this work extend the importance of Hückel aromaticity concept to excited triplet states which are usually characterized by the Baird type of (anti)aromaticity.
    Language English
    Publishing date 2022-01-18
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2233006-9
    ISSN 1861-471X ; 1861-4728
    ISSN (online) 1861-471X
    ISSN 1861-4728
    DOI 10.1002/asia.202101261
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  8. Article ; Online: Can Variations of

    Baranac-Stojanović, Marija

    Chemistry, an Asian journal

    2018  Volume 13, Issue 7, Page(s) 877–881

    Abstract: The classical textbook explanation of variations ... ...

    Abstract The classical textbook explanation of variations of
    Language English
    Publishing date 2018-04-04
    Publishing country Germany
    Document type Journal Article
    ISSN 1861-471X
    ISSN (online) 1861-471X
    DOI 10.1002/asia.201800137
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Substituent Effect on Triplet State Aromaticity of Benzene

    Baranac-Stojanović, Marija

    Journal of organic chemistry. 2020 Feb. 18, v. 85, no. 6

    2020  

    Abstract: Density functional theory calculations have been performed to explore the substituent effect on benzene’s structure and aromaticity upon excitation to the first triplet excited state (T1). Discussion is based on spin density analysis, HOMA (harmonic ... ...

    Abstract Density functional theory calculations have been performed to explore the substituent effect on benzene’s structure and aromaticity upon excitation to the first triplet excited state (T1). Discussion is based on spin density analysis, HOMA (harmonic oscillator model of aromaticity), NICS (nucleus-independent chemical shift), ACID (anisotropy of the induced current density), and monohydrogenation free energies and shows that a large span of aromatic properties, from highly antiaromatic to strongly aromatic, could be achieved by varying the substituent. This opens up a possibility of controlling benzene’s physicochemical behavior in its excited state, while molecular motion, predicted for several derivatives, could be of interest for the development of photomechanical materials.
    Keywords anisotropy ; benzene ; chemical reactions ; chemical structure ; density functional theory ; models
    Language English
    Dates of publication 2020-0218
    Size p. 4289-4297.
    Publishing place American Chemical Society
    Document type Article
    ZDB-ID 123490-0
    ISSN 1520-6904 ; 0022-3263
    ISSN (online) 1520-6904
    ISSN 0022-3263
    DOI 10.1021/acs.joc.9b03472
    Database NAL-Catalogue (AGRICOLA)

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    In stock of ZB MED Bonn / Germany

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  10. Article ; Online: The effect of two types of dibenzoannulation of pentalene on molecular energies and magnetically induced currents.

    Baranac-Stojanović, Marija / Stojanović, Milovan

    Physical chemistry chemical physics : PCCP

    2019  Volume 21, Issue 6, Page(s) 3250–3263

    Abstract: The effect of two types of dibenzo-fusion of pentalene in the singlet and triplet states on its molecular energies and magnetically induced ring currents was examined via density functional calculations. The isomerization energy decomposition analysis ( ... ...

    Abstract The effect of two types of dibenzo-fusion of pentalene in the singlet and triplet states on its molecular energies and magnetically induced ring currents was examined via density functional calculations. The isomerization energy decomposition analysis (IEDA) together with the calculated aromaticity indices (NICS(1)zz, HOMA and FLUπ), estimation of resonance energies (RE) and extra cyclic resonance energies (ECRE) via the NBO method, and the NICS-XY-scans revealed that the π-electronic system is the most important factor controlling the molecular energies. The [a,f] topology features greater delocalization, which results in two opposing effects: larger ECRE, but weaker π-bonding. The latter is mainly responsible for the higher energy of [a,f]-dibenzopentalene (DBP) (ΔEiso = 21.7 kcal mol-1), with the other effects being σ-orbital and electrostatic interactions. The reversal of energetic stability in the triplet states (ΔEiso = -10.8 kcal mol-1) mainly comes from the reduced Pauli repulsion in [a,f]-DBP, which stabilizes the unpaired spin density over the central trimethylenemethane subunit vs. the central pentalene subunit in [a,e]-DBP. Although the [a,e] topology only reduces the diatropic and paratropic currents of the elementary subunits, benzene and pentalene, the [a,f] topology also creates strong global paratropicity involving the benzene rings. Both DBP isomers are characterized by global and smaller semi-global and local diatropic currents in the triplet state.
    Language English
    Publishing date 2019-01-14
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/c8cp07875k
    Database MEDical Literature Analysis and Retrieval System OnLINE

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