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• Planting phytase transgenic maize can not affect arthropod community composition. • Arthropod community diversity of two maize varieties has no significant difference. • Arthropod community in two maize plots is highly similar. • Planting phytase transgenic maize can not affect arthropod community stability. It is important to understand the effect of phytase transgenic (PT) maize on arthropod communities in natural ecosystems. In this study, a 2-year survey of arthropod community biodiversity in fields of PT maize (0 7 8) and non-genetically modified (RA119, non-GM) maize was performed using sweep-net sampling on the stems and leaves of the maize plants. The results showed that there was no significant difference in the individual number of herbivorous, predatory, neutral and parasitic groups in PT maize and non-GM maize. The species number of herbivorous group in PT maize was significantly lower than that in non-GM maize in 2013 (p < 0.05). The proportions of different arthropod groups were almost identical in the PT maize and non-GM maize in terms of both species and individual number. Moreover, there was no significant difference in the Shannon-Weiner diversity index (H'), evenness index (J), dominance index (D), richness (S), and species abundance (N) between the two types of maize. The similarity coefficient of the arthropod community suggested that the arthropod community composition of PT maize was similar to that of non-GM maize. Furthermore, PT maize had no significant effect on the relative stability of the arthropod community. These results indicated that despite the presence of a relatively minor difference in arthropod community between the PT maize and non-GM maize, the PT maize had little effect on arthropod community biodiversity. [ABSTRACT FROM AUTHOR]

The results of a detailed DFT (B3LYP) investigation on five tautomers of thiazolidine-2,4-dione and their 5-substituted derivatives ( CH 3 , NH 2 , Cl, F, CN- and NO 2 ) are presented here. The energy, geometrical parameters, topological parameters of all species in the gas phase have been calculated at B3LYP6–311++G(3df,2p)//B3LYP/311 + G(d,p) level of theory. The proton affinities (Pas), molecular electrostatic potential (MEP), natural valence atomic orbital energies (NNAO) of the basic center exist in the title compound in the gas phase have been calculated at the same level of theory. The specific hydration of the title compound by one water molecule has been also investigated at the same level of theory. Among the thiazolidine-2,4-dione tautomers and its derivatives, the most stable tautomer corresponds to the diketo forms (A), regardless of the substituent type. Results reveal that the oxygen atom of the carbonyl group at position 2 is more basic than the one at position 4. The existence of different hydrogen bond donor and acceptor centers in these molecules led to different kinds of intermolecular hydrogen bonds (CH···O, N H···O and C O···H) and different kinds of complexes. The stability of the cyclic complexes has been investigated using the analysis of Natural Bond Orbital (NBO), Atoms In Molecules topology, and the thermodynamic data. Results suggest that the water molecule prefers to bind with the oxygen atom, which has low intrinsic character. [ABSTRACT FROM AUTHOR]

We use inverse design of materials by multi-objective differential evolution (IM 2 ODE) method to globally search the most stable configurations of Au n , Au n - 1 Pt, Au n - 2 Pt 2 ( n = 2–9) clusters. Combining with first-principles calculations, based on the density functional theory (DFT), we find that all of the ground state structures of clusters prefer to keep low spin multiplicity and form planar structures. Pt atom tends to occupy the most highly coordinated position. Especially Au 6 Pt and Au 4 Pt 2 clusters exhibit highly relative stability and have a closed electronic shell based on the spherial jellium model, so we conclude that Au 6 Pt and Au 4 Pt 2 should be magic number clusters. Mulliken occupation analysis of Pt and Au atoms indicate that a competition exits between electronegativity of atoms and valence electron configuration of atoms in small Au n Pt m clusters. [ABSTRACT FROM AUTHOR]

The geometries, stabilities, and electromagnetic characteristics of CY n ( n = 1–14) clusters have been systematically investigated using relativistic density functional theory with the generalized gradient approximation. The growth process of CY n ( n = 1–14) clusters can be divided into three phases. First, the C atom replaces a surface atom of Y n +1 cluster when n < 6. For the cluster with n = 6, the C atom goes into the center of a tetragonal bipyramid and the C@Y 6 cluster is formed. Over the range from n = 7 to 14, Y atoms are successively capped onto the C@Y 6 sub-cluster. Due to the C doping, the stability of clusters is enhanced and the magnetic moments are reduced compared to the corresponding pure yttrium clusters. In particular, doping with a carbon atom whether at the surface or in the subsurface can make some clusters transition from an open electronic shell to a closed electron shell. [ABSTRACT FROM AUTHOR]

The relative stability of N1 and N3 anions of twelve 5,6-substituted uracils in aqueous solutions was studied in IEFPCM (SMD) – TPSSTPSS/6-311+G(d,p) approximation. Specific solvation was simulated by the first hydrate shell of uracil and anions containing 5 water molecules. Based on Δ G water = G 0 (N3) − G 0 (N1), the series of relative stability was determined as: 5OH6MeU (−3.4) – 5OHU (−2.0) – 5NH 2 U (2.4) – U (3.5) – 5FU (4.5) – 5MeU (4.6) – 6MeU (4.6) – 5ClU (9.2) – 5BrU (9.5) – 5NO 2 U (18.6) – 6ClU (31.9) – 6FU (33.9), kJ/mol. The factors that determine the relative stability in the N1/N3 pair were identified. In the gas phase, the N1 anion is much more stable than the N3 anion: Δ G gas varies in the range from 23.3 ( 5OHU ) to 80.0 ( 6FU ) kJ/mol due to more efficient delocalization of excess charge over the uracil frame in the N1 anion, which was characterized using HOMA aromaticity indices. The solvent makes the Gibbs energies of the N1 and N3 states much more close. Two reasons of the stabilizing effect of water can be distinguished. First, the aromaticity of N3 anions increases considerably in aqueous solutions, leading to almost complete equalization of HOMA indices. Second, the polar solvent more efficiently stabilizes the more polar N3 states of the uracils studied. The effect of substituents on the relative stability Δ G water was studied using the Hammett method. It was found that substituents with a strong (+R)-effect at position 5 decreased Δ G water down to negative values. Substituents at position 6 affect the relative stability of uracil anions by the inductive mechanism. In this case the formation of N1 anions becomes much more preferable than the formation of N3 anions. The mesomeric effect is weak in this case. [ABSTRACT FROM AUTHOR]

The existing literature on fractional-order interval systems (FOISs) shows that the Kharitonov's theorem fails to check the stability of the FOIS (Tan et al. in ISA Trans 48:166-172, ). Therefore, in this note, it is shown that the relative stability analysis of fractional-order interval systems can be carried out using only four polynomials concept of Kharitonov's theorem. Thus, there is no need to use Edge theorem which needs to check $$2^{\left( {n+1} \right) }$$ polynomials for $$\left( {n+1} \right) $$ uncertain parameters for stability analysis of FOIS. The proposed approach is applicable to both commensurate and incommensurate classes of fractional-order interval systems. The results are verified for various numerical examples and models of Heating furnace system and Gas turbine plant. [ABSTRACT FROM AUTHOR]

Two isomers of each nitrogen-doped fullerenes C 42 N 18 and C 40 N 20 have been studied, including those with separated nitrogen atoms and those with a nitrogen belt in a chain form in equator of these molecules. All computations have been carried out using Gaussian 03 and NBO 5.0 programs, employing HF and DFT (at B3LYP level) methods at different basis sets. Several structural parameters for each of the isomers have been studied and the results for the isomers with a nitrogen belt have been compared with those of the isomers with separated nitrogen atoms and also with those of C 60 fullerene. The structural studies show that the nitrogen belt isomers, with more all-carbon hexagonal and some nonagonal and decagonal rings, have reasonable stability. The electronic properties such as atomization energy, ionization potential, electron affinity, electronegativity, HOMO/LUMO surface energies and their gap, dipole moment, polarizability, hyperpolarizability, NBO charges and harmonic vibrational frequencies of the target compounds and C 60 fullerene have been calculated. The results show that the isomers with a belt of the nitrogen atoms could have reasonable stabilities, showing relatively high electron accepting characters. They also could form donor–acceptor pairs with electron-donor compounds having close HOMO–LUMO gap, such as the isomers containing separated nitrogen atoms, and could be used for potential applications in molecular electronics. [ABSTRACT FROM AUTHOR]

One of the oldest elements of the Common Fisheries Policy (CFP) is the principle of ‘relative stability’. Relative stability means that yearly established Total Allowable Catches (TACs) for each fish stock are divided between the Member States of the European Union (EU) according to a fixed allocation key. One way to circumvent the relative stability is the (increasing) practice of swapping quota with other Member States. These swaps have a temporary character, but continuously repeated yearly swaps occur. In recent decades many Member States have shifted resource management responsibilities more towards the industry and the process of quota swapping is in several Member States managed by Producers Organisations (POs) rather than by government administrations. Networks of fishermen and POs try to establish solid relationships and try to put at the same time stability and flexibility into the system. Information and networks play an important role in the process of quota swapping. However, not all POs and fishermen tend to have (equal) access to the required information for quota swapping which raises questions on how transparent this process is. With the upcoming implementation of the landing obligation, the quota swaps between Member States are expected to increase further. This paper describes the extent and the practice of quota swapping, the implications for one of the principles of good governance, transparency, as well as the effects of swapping for the relative stability. [ABSTRACT FROM AUTHOR]

The structures and electronic properties of a series small mixed aluminum boron clusters AlB n - and Al 2 B n - ( n = 1−9) have been investigated systematically with the density functional approach. Results show that the ground state prefers the lowest spin state except Al 2 B - and the Al atom tends to be adsorbed at the surface in both boron–aluminum systems. Moreover, results about the stability indicate clusters AlB 8 - and Al 2 B 7 - have the considerable enhanced stability among the clusters of AlB n - and Al 2 B n - ( n = 1−9). Besides, the electronic and magnetic properties for two systems are also investigated, and the total magnetic moments as a function of cluster size show a dramatic odd–even alternative behavior for clusters AlB n - , while the addition of one more Al atom makes the total magnetic moments of the clusters Al 2 B n - contrary except n = 1. [ABSTRACT FROM AUTHOR]

Highlights: [•] The lowest energy structures of AgAu n − 1 keep a higher relative stability than their neighboring odd-numbered ones. [•] The AgAun − 1 dissociate Ag atom while the even-numbered ones dissociate AgAu dimer. [•] The even-numbered AgAu n − 1 keep a higher relative stability than their neighboring odd-numbered ones. [•] The AgAu5 cluster shows the strongest stability. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ti atom in Au n Ti clusters tends to occupy the most highly coordinated position. [•] The doping of a Ti atom enhances the stability of gold clusters. [•] The Au n Ti cluster with even n exhibit higher stability over the cluster with odd n. [•] The chemical activity of gold cluster is changed by a Ti atom. [•] The magnetic moment of Ti atom in Au n Ti (n =3–9) clusters is quenched for even n. [Copyright &y& Elsevier]

Highlights: [•] Molecular geometric structures of 287 polychlorinated pyrenes (PCPYs) were optimized. [•] Some thermodynamic properties for PCPYs were obtained. [•] Some of PCPY isomers have a nonplanar configuration. [•] Δf H ∘ And Δf G ∘ of PCPYs show a strong dependence on the relative positions of Cl atoms. [•] Intramolecular adjacent Cl⋯Cl nuclear repulsive interaction determines stability of PCPYs. [Copyright &y& Elsevier]

Abstract: The geometrical structures, relative stabilities, electronic and magnetic properties of the (1⩽ n ⩽8) clusters are systematically investigated by the first-principles density functional calculations at the PW91PW91 level. The results show that doping with a single Al atom can dramatically affect the ground-state geometries of the clusters. The calculated fragmentation energy, second-order difference of the total energies and the highest occupied-lowest unoccupied molecular orbital (HOMO–LUMO) energy gaps exhibit an interesting, oscillatory behavior as a function of the cluster size. Furthermore, both the total and local magnetic moments display an obvious even–odd alternation phenomenon with the number of gold atoms. [Copyright &y& Elsevier]

Abstract: The equilibrium geometries, relative stabilities, both vertical and adiabatic of ionization potentials and electron affinities as well electronic properties of Al n and Al n −1Mg (n =2–17) clusters have been systematically investigated by using B3LYP/6-311G(d). In general, the ground state structures of Al n −1Mg clusters have similar geometries as the host Al n clusters, except for Al4Mg. Starting from n =7, the Mg atom prefers to stay away from the center of Al n clusters and locate on the site of the corresponding Al n clusters surface. The dissociation energy of the Al n −1Mg clusters dissociate into Al n −1 clusters with one Mg atom are lower than those dissociate into Al n −2Mg clusters with one Al atom, which suggests that the Al n −1Mg clusters are likely to break into Al n −1 clusters with one Mg atom. The results of AEA and VEA, AIP and VIP and second-order difference energy indicate that the Al n −1Mg (n =3, 5, 7, 9, 11, 13, 15, and 17) clusters are more stable than others, which reveals that the chemical activity of Al n −1Mg clusters are diminished. The electronic structure has been discussed and the results of natural charge population analysis shows that there is a charge transfer from 3s states of Mg atom to 3p states of Al atoms resulting in the strong s-p hybridization. [ABSTRACT FROM AUTHOR]

Abstract: The geometrical structures, relative stabilities, electronic and magnetic properties of small Al n Fe− (1≤ n ≤9) clusters, in comparison with pure aluminum clusters have been systematically investigated by means of density functional calculations at the BPW91 level. The resulting geometries show that the frameworks of the lowest energy Al n Fe− clusters prefer to be three-dimensional structures. Here, the relative stabilities are investigated in terms of the calculated average binding energies, fragmentation energies, and second-order difference of energies. Moreover, the result of the highest occupied-lowest unoccupied molecular orbital energy gaps indicates that Al3Fe− cluster has the highest chemical stability for Al n Fe− (1≤ n ≤9) clusters. Furthermore, the natural population analysis reveals that the charges in Al n Fe− clusters transfer from the Al frames to the Fe atom. Additionally, the analyses of the local and total magnetic moments of Al n Fe− clusters show that the magnetic influence mainly come from the Fe atom. [Copyright &y& Elsevier]

Abstract: Classical and heptagon-contained nonclassical fullerene isomers of C30–C40 and C50 are generated by Spiral algorithm and optimized using DFT methods. There are much larger number of nonclassical isomers than classical ones. Energies of isomers generally increase with the number of heptagons inside and those lowest-energy nonclassical isomers contain only one heptagon. For all fullerenes considered, there is no nonclassical isomer that energetically prevails over the lowest-energy classical counterpart. But the best nonclassical isomers are more stable than most classical ones. The validity of pentagon adjacency penalty rule (PAPR) and hexagon neighbor rule (HNR) is examined for the nonclassical fullerenes. PAPR is still roughly applicable while HNR almost breaks down. A new topological index U with better performance over PAPR and HNR is presented and its superiority is further confirmed on two subsets of C50 isomers. This U index can be considered as an extension of PAPR to nonclassical isomers with existence of heptagons. [ABSTRACT FROM AUTHOR]

• Structural evolution for global minimum CeSi n 0/− is explored. • The spectral information is reported. • The 4 f electron of Ce atom in CeSi n 0/− does not participate in bonding. • HOMO-LUMO gap, relative stability and chemical bonding analyses is evaluated. • The superatom is assigned to be CeSi 20 −. Structural evolution model, HOMO-LUMO gap, relative stability, magnetic moment and spectral property of nanosize CeSi n 0/− (n = 4–20) semiconductor material were performed by employing double-hybrid density functional scheme. Optimized geometries for CeSi n displayed that the most stable structure is Ce-substituted for a Si in the ground state of Si n +1 with n ≤ 17; Ce atom as linker connects two small silicon subclusters with n = 17–19; and Ce atom is encapsulated into cage-like Si framework with ≥20. For anion, the most stable structure of CeSi n − is Ce-linked configuration with n = 8–18 excluded n = 9, and Ce atom is encapsulated into cage-like motif with n = 19–20. The spectral information was reported. The 4 f electron of Ce atom in CeSi n 0/− does not participate in bonding, resulting the total magnetic moments of neutral and anionic CeSi n 0/− clusters are 2 and 1 μ B , respectively. HOMO-LUMO gap, relative stability and chemical bonding analyses revealed that encapsulated configuration of CeSi 20 − is a "magic" cluster. [ABSTRACT FROM AUTHOR]

Distribution of fisheries resources is based on the principle of relative stability, from which the total allowable catches (TACs) are divided into national quotas based each year on a fixed percentage per stock. This does not fit well with the interaction of economic dynamics of fishing fleets and the Community's legal framework (right of establishment, free movement of workers). This has led to the so-called'quota-hopping'. The Member State can nevertheless require a ship under its flag to have a 'real economic link'. But this is too vague toafford fisheries-dependent regions an efficient tool to meet their demands. [ABSTRACT FROM AUTHOR]