Showing papers by "Romanian Academy published in 2015"
European Southern Observatory1, Liverpool John Moores University2, University of Western Australia3, University of St Andrews4, Max Planck Society5, Ames Research Center6, Australian Astronomical Observatory7, University of the Western Cape8, Durham University9, University of Sussex10, University of Melbourne11, University of Nottingham12, University of Sydney13, Monash University, Clayton campus14, University of Queensland15, University of Edinburgh16, University of Central Lancashire17, Australian National University18, University of Turku19, University of Canterbury20, University of Oxford21, University of Hertfordshire22, Leiden University23, Institute of Cosmology and Gravitation, University of Portsmouth24, National Institute of Astrophysics, Optics and Electronics25, Macquarie University26, National Autonomous University of Mexico27, Carnegie Institution for Science28, University of Bristol29, University of Hull30, Romanian Academy31, Queen Mary University of London32, University of Innsbruck33
TL;DR: The Galaxy And Mass Assembly (GAMA) survey as mentioned in this paper is one of the largest contemporary spectroscopic surveys of low redshift galaxies, covering an area of ∼286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, and collecting spectra and reliable redshifts for 238'000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope.
Abstract: The Galaxy And Mass Assembly (GAMA) survey is one of the largest contemporary spectroscopic surveys of low redshift galaxies. Covering an area of ∼286 deg2 (split among five survey regions) down to a limiting magnitude of r < 19.8 mag, we have collected spectra and reliable redshifts for 238 000 objects using the AAOmega spectrograph on the Anglo-Australian Telescope. In addition, we have assembled imaging data from a number of independent surveys in order to generate photometry spanning the wavelength range 1 nm–1 m. Here, we report on the recently completed spectroscopic survey and present a series of diagnostics to assess its final state and the quality of the redshift data. We also describe a number of survey aspects and procedures, or updates thereof, including changes to the input catalogue, redshifting and re-redshifting, and the derivation of ultraviolet, optical and near-infrared photometry. Finally, we present the second public release of GAMA data. In this release, we provide input catalogue and targeting information, spectra, redshifts, ultraviolet, optical and near-infrared photometry, single-component Sersic fits, stellar masses, Hα-derived star formation rates, environment information, and group properties for all galaxies with r < 19.0 mag in two of our survey regions, and for all galaxies with r < 19.4 mag in a third region (72 225 objects in total). The data base serving these data is available at http://www.gama-survey.org/.
494 citations
TL;DR: In this paper, the authors tried to reveal the role of human capital as a factor of the growth and argue that the slow investment in human capital should influence the sustainable development of the countries.
Abstract: The EU's 2020 Strategy is focused on three area of growth: smart, sustainable and inclusive that couldn’t be achieved without major contribution of skills, knowledge or value of people, common knew as human capital. It is difficult to believe that these goals could be realized without a good education and training system, a large diffusion of knowledge in manufacturing services, a creative industries and a great effort to create a research-intensive economy. Using a panel methodology, the paper tried to reveal the role of human capital as a factor of the growth and to argue that the slow investment in human capital should influence the sustainable development of the countries.
267 citations
University of Novi Sad1, Uppsala University2, Lamont–Doherty Earth Observatory3, University of Bayreuth4, Max Planck Society5, University of Cambridge6, ETH Zurich7, Chinese Academy of Sciences8, University of Leicester9, Hungarian Academy of Sciences10, University of Szeged11, Babeș-Bolyai University12, Romanian Academy13, University of Mainz14, University of Wrocław15, University of Copenhagen16, Serbian Academy of Sciences and Arts17, RWTH Aachen University18, University of Pécs19
TL;DR: In this article, a new Danube Basin wide loess stratigraphy based on a synthetic type section of the Mosorin and Stari Slankamen sites in Serbia is presented.
247 citations
TL;DR: In this paper, the qualitative analysis of solutions to nonlinear elliptic problems of the type { − div A (x, ∇ u ) = λ | u | q (x ) − 2 u in Ω u = 0 on ∂ Ω, where Ω is a bounded or an exterior domain of R N and q is a continuous positive function.
Abstract: In this survey paper, by using variational methods, we are concerned with the qualitative analysis of solutions to nonlinear elliptic problems of the type { − div A ( x , ∇ u ) = λ | u | q ( x ) − 2 u in Ω u = 0 on ∂ Ω , where Ω is a bounded or an exterior domain of R N and q is a continuous positive function. The results presented in this paper extend several contributions concerning the Lane–Emden equation and we focus on new phenomena which are due to the presence of variable exponents.
218 citations
TL;DR: In this article, the existence of multiple ground state solutions for a class of parametric fractional Schrodinger equations whose simplest prototype is (−�) s u + V (x)u = λ f (x, u) in R n, where n > 2, s stands for the fractional Laplace operator of order s ∈ (0, 1),a ndλ is a positive real parameter.
Abstract: In this paper, we study the existence of multiple ground state solutions for a class of parametric fractional Schrodinger equations whose simplest prototype is (−�) s u + V (x)u = λ f (x, u) in R n , where n > 2 ,( −�) s stands for the fractional Laplace operator of order s ∈ (0,1) ,a ndλ is a positive real parameter. The nonlinear term f is assumed to have a superlinear behaviour at the origin and a sublinear decay at infinity. By using variational methods, we establish the existence of a suitable range of positive eigenvalues for which the problem admits at least two nontrivial solutions in a suitable weighted fractional Sobolev space. Mathematics Subject Classification 35A15 · 35S15 · 49J35 · 45G05 · 47G20
207 citations
TL;DR: In this paper, Ghiba et al. showed that the presence of band-gaps is related to a unique elastic coefficient, the so-called Cosserat couple modulus, which is also responsible for the loss of symmetry of the Cauchy force stress tensor.
Abstract: In this paper, the relaxed micromorphic model proposed in Ghiba et al. (Math Mech Solids, 2013), Neff et al. (Contin Mech Thermodyn, 2013) has been used to study wave propagation in unbounded continua with microstructure. By studying dispersion relations for the considered relaxed medium, we are able to disclose precise frequency ranges (band-gaps) for which propagation of waves cannot occur. These dispersion relations are strongly nonlinear so giving rise to a macroscopic dispersive behavior of the considered medium. We prove that the presence of band-gaps is related to a unique elastic coefficient, the so-called Cosserat couple modulus μ
c
, which is also responsible for the loss of symmetry of the Cauchy force stress tensor. This parameter can be seen as the trigger of a bifurcation phenomenon since the fact of slightly changing its value around a given threshold drastically changes the observed response of the material with respect to wave propagation. We finally show that band-gaps cannot be accounted for by classical micromorphic models as well as by Cosserat and second gradient ones. The potential fields of application of the proposed relaxed model are manifold, above all for what concerns the conception of new engineering materials to be used for vibration control and stealth technology.
139 citations
TL;DR: Two circulating miRNAs that in association with some lipid metabolism biomarkers can be used as an additional tool to designate vulnerable CAD patients are identified.
Abstract: Small non-coding microRNAs (miRNAs) are implicated in gene regulation, including those involved in coronary artery disease (CAD). Our aim was to identify whether specific serum miRNAs present in the circulating lipoproteins (Lp) are associated with stable or vulnerable CAD patients. A cardiovascular disease-focused screening array was used to assess miRNAs distribution in sera collected from 95 CAD patients: 30 with stable angina (SA), 39 with unstable angina (UA), 26 at one month after myocardial infarction (MI) and 16 healthy control subjects. We found that miR-486, miR-92a and miR-122 presented the highest expression in CAD sera. These miRNA together with miR-125a, miR-146a and miR-33a were further individually analyzed by TaqMan assays. The results were consistent with PCR-array screening data that all of these miRNAs were significantly increased in CAD patients compared to controls. Using a binary logistic regression model, we established that miR-486 and miR-92a in association with some high-density lipoprotein (HDL) components can designate vulnerable CAD patients. Further, all classes of Lp were isolated from sera by density gradient ultracentrifugation. Analysis of the selected miRNAs in each Lp class showed that they were associated mainly with HDL, miR-486 and miR-92a having the highest levels. In UA and MI patients, miR-486 prevailed in HDL2, while miR-92a prevailed in HDL3, and their levels discriminate between stable and vulnerable CAD patients. We identified two circulating miRNAs that in association with some lipid metabolism biomarkers can be used as an additional tool to designate vulnerable CAD patients.
131 citations
TL;DR: In this article, the sustainability of bio-derived succinic acid (Bio-SA) via fermentative synthesis was studied through two different processes (Myriant and Reverdia cases) and compared with the corresponding petrochemical route.
131 citations
TL;DR: In this paper, a model of dry granular flows is proposed that quantitatively reproduce laboratory experiments of granular column collapse over inclined planes, and the rheological parameters are directly derived from the experiments.
Abstract: A mechanical and numerical model of dry granular flows is proposed that quantitatively reproduce laboratory experiments of granular column collapse over inclined planes. The rheological parameters are directly derived from the experiments. The so-called μ ( I ) rheology is reformulated in the framework of Drucker–Prager plasticity with the yield stress and viscosity η ( ‖ D ‖ , p ) depending on both the pressure p and the norm of the strain rate tensor ‖ D ‖ . The granular domain, velocities, stress deviator and pressure fields are calculated using a finite element method based on an iterative decomposition–coordination formulation coupled with the augmented Lagrangian method. 2-D simulations using this model well reproduce the dynamics and deposits of collapsing granular columns. The flow is essentially located in a surface layer behind the front, whereas it is distributed over the whole depth near the front where basal sliding occurs. The computed runout distances and slopes of the deposits agree very well with the values found in the experiments. Using an easily calculated order of magnitude approximation of the mean viscosity during the flow ( η = 1 Pa s here), we show that a Drucker–Prager rheology with a constant viscosity gives results very similar to the μ ( I ) rheology and agrees with experimental height profiles, while significantly reducing the computational cost. Within the range of viscosities 0.1 η 1 Pa s, the dynamics and deposits are very similar. The observed slumping behavior therefore appears to be mainly due to the flow/no-flow criterion and to the associated strain-independent part of the “flowing constitutive relation” (i.e. related to plastic effects). However, the results are very different when an unrealistically large value of viscosity (10 Pa s) is used.
127 citations
TL;DR: This review focuses on the structural and magnetic characterization of the cores, the synthesis of single- and multicore iron oxide NPs, especially the design of the latter, as well as their protection, stabilization and functionalization by desired coating in order to protect against the corrosion of core, to prevent non-specific protein adsorption and particle aggregation in biological media, and to provide binding sites for targeting and therapeutic agents.
123 citations
TL;DR: Individualized therapy, targeting the process of EMT and its cross-linking with cancer stem cells, may increase survival of patients with pancreatic cancer.
TL;DR: In this paper, a family of isotropic volumetric-isochoric decoupled strain energies was investigated and the rank-one convexity of these energies was shown in plane elastostatics.
Abstract: We investigate a family of isotropic volumetric-isochoric decoupled strain energies $$\begin{aligned} F\mapsto W_{\mathrm{eH}}(F):=\widehat{W}_{\mathrm{eH}}(U):=\left \{ \begin{array}{l@{\quad}l} \frac{\mu}{k} e^{k\|\operatorname {dev}_n\log{U}\|^2}+\frac{\kappa}{{2 {\widehat {k}}}} e^{\widehat{k}[\operatorname {tr}(\log U)]^2}&\text{if}\ \det F>0,\\ +\infty&\text{if}\ \det F\leq0, \end{array} \right . \end{aligned}$$ based on the Hencky-logarithmic (true, natural) strain tensor logU, where μ>0 is the infinitesimal shear modulus, $\kappa=\frac{2\mu+3\lambda}{3}>0$
is the infinitesimal bulk modulus with λ the first Lame constant, $k,\widehat{k}$
are additional dimensionless material parameters, F=∇φ is the gradient of deformation, $U=\sqrt{F^{T} F}$
is the right stretch tensor and is the n-dimensional deviatoric part of the strain tensor logU. For small elastic strains, W
eH approximates the classical quadratic Hencky strain energy $$\begin{aligned} F\mapsto W_{\mathrm{H}}(F):=\widehat{W}_{\mathrm{H}}(U)&:={\mu}\| \operatorname {dev}_n\log U\|^2+\frac{\kappa}{2}\bigl[\operatorname{tr}( \log U)\bigr]^2, \end{aligned}$$ which is not everywhere rank-one convex. In plane elastostatics, i.e., n=2, we prove the everywhere rank-one convexity of the proposed family W
eH, for $k\geq\frac{1}{4}$
and $\widehat{k}\geq\frac{1}{8}$
. Moreover, we show that the corresponding Cauchy (true)-stress-true-strain relation is invertible for n=2,3 and we show the monotonicity of the Cauchy (true) stress tensor as a function of the true strain tensor in a domain of bounded distortions. We also prove that the rank-one convexity of the energies belonging to the family W
eH is not preserved in dimension n=3 and that the energies $$\begin{aligned} F\mapsto\frac{\mu}{k}e^{k\|\log U\|^2},\qquad F\mapsto\frac{\mu }{k}e^{\frac{k}{\mu} \bigl(\mu\|\operatorname {dev}_n\log U\|^2+\frac{\kappa}{2}[\operatorname {tr}(\log U)]^2 \bigr)}, \quad F \in\mathrm{GL}^+(n), n\in \mathbb {N}, n\geq2 \end{aligned}$$ are also not rank-one convex.
University of St Andrews1, University of Western Australia2, Max Planck Society3, University of the Western Cape4, Macquarie University5, Australian Astronomical Observatory6, University of Melbourne7, University of Nottingham8, University of Sydney9, Monash University, Clayton campus10, Australian National University11, University of Edinburgh12, European Southern Observatory13, National Autonomous University of Mexico14, University of Sussex15, Carnegie Institution for Science16, Indian Institute of Science Education and Research, Mohali17, Durham University18, University of Hull19, University of Central Lancashire20, Romanian Academy21
TL;DR: In this paper, the authors explore trends in galaxy properties with Mpc-scale structures using catalogues of environment and large-scale structure from the Galaxy And Mass Assembly (GAMA) survey.
Abstract: We explore trends in galaxy properties with Mpc-scale structures using catalogues of environment and large-scale structure from the Galaxy And Mass Assembly (GAMA) survey. Existing GAMA catalogues of large-scale structure, group, and pair membership allow us to construct galaxy stellar mass functions for different environmental types. To avoid simply extracting the known underlying correlations between galaxy properties and stellar mass, we create a mass matched sample of galaxies with stellar masses within 9.5 ≤ log M*/h−2 M⊙ ≤ 11 for each environmental population. Using these samples, we show that mass normalized galaxies in different large-scale environments have similar energy outputs, u − r colours, luminosities, and morphologies. Extending our analysis to group and pair environments, we show that galaxies that are not in groups or pairs exhibit similar characteristics to each other regardless of broader environment. For our mass controlled sample, we fail to see a strong dependence of Sersic index or galaxy luminosity on halo mass, but do find that it correlates very strongly with colour. Repeating our analysis for galaxies that have not been mass controlled introduces and amplifies trends in the properties of galaxies in pairs, groups, and large-scale structure, indicating that stellar mass is the most important predictor of the galaxy properties we examine, as opposed to environmental classifications.
TL;DR: This review article summarizes some of the recent advances and concepts related to the regulation of Nox expression in the vascular pathophysiology and highlights the role of transcription factors and epigenetic mechanisms in this process.
Abstract: NADPH oxidases (Nox) represent a family of hetero-oligomeric enzymes whose exclusive biological function is the generation of reactive oxygen species (ROS). Nox-derived ROS are essential modulators of signal transduction pathways that control key physiological activities such as cell growth, proliferation, migration, differentiation, and apoptosis, immune responses, and biochemical pathways. Enhanced formation of Nox-derived ROS, which is generally associated with the up-regulation of different Nox subtypes, has been established in various pathologies, namely cardiovascular diseases, diabetes, obesity, cancer, and neurodegeneration. The detrimental effects of Nox-derived ROS are related to alterations in cell signalling and/or direct irreversible oxidative damage of nucleic acids, proteins, carbohydrates, and lipids. Thus, understanding of transcriptional regulation mechanisms of Nox enzymes have been extensively investigated in an attempt to find ways to counteract the excessive formation of Nox-derived ROS in various pathological states. Despite the numerous existing data, the molecular pathways responsible for Nox up-regulation are not completely understood. This review article summarizes some of the recent advances and concepts related to the regulation of Nox expression in the vascular pathophysiology. It highlights the role of transcription factors and epigenetic mechanisms in this process. Identification of the signalling molecules involved in Nox up-regulation, which is associated with the onset and development of cardiovascular dysfunction may contribute to the development of novel strategies for the treatment of cardiovascular diseases.
TL;DR: In this paper, the one-shot carboxylation of microcrystalline cellulose in the presence of nitroxyl radicals and sodium periodate has been investigated, and the results show that it is possible to obtain a 1.
Abstract: Correction for ‘One-shot carboxylation of microcrystalline cellulose in the presence of nitroxyl radicals and sodium periodate’ by Sergiu Coseri et al., RSC Adv., 2015, 5, 85889–85897.
TL;DR: It was concluded that the reversibility of imine forming promotes the self-assembling of imino-chitosan biopolymer films into a lamellar morphology and, on the other hand, the slow release of the antimicrobial aldehyde in the microbiological culture.
University of Western Australia1, University of St Andrews2, Liverpool John Moores University3, University of Sydney4, Australian Astronomical Observatory5, Monash University, Clayton campus6, University of the Western Cape7, University of Queensland8, Max Planck Society9, National Autonomous University of Mexico10, Macquarie University11, University of Sussex12, Durham University13, University of Central Lancashire14, Romanian Academy15, University of Turku16, Mount Stromlo Observatory17, Netherlands Institute for Space Research18, University of Edinburgh19, University of Canterbury20, Cardiff University21
TL;DR: In this article, the authors investigate the link between dynamical phase and direct measures of star formation on different time-scales for pair galaxies, targeting numerous star-formation rate (SFR) indicators and comparing to pair separation, individual galaxy mass and pair mass ratio.
Abstract: The modification of star formation (SF) in galaxy interactions is a complex process, with SF observed to be both enhanced in major mergers and suppressed in minor pair interactions. Such changes likely to arise on short time-scales and be directly related to the galaxy–galaxy interaction time. Here we investigate the link between dynamical phase and direct measures of SF on different time-scales for pair galaxies, targeting numerous star- formation rate (SFR) indicators and comparing to pair separation, individual galaxy mass and pair mass ratio. We split our sample into the higher (primary) and lower (secondary) mass galaxies in each pair and find that SF is indeed enhanced in all primary galaxies but suppressed in secondaries of minor mergers. We find that changes in SF of primaries are consistent in both major and minor mergers, suggesting that SF in the more massive galaxy is agnostic to pair mass ratio. We also find that SF is enhanced/suppressed more strongly for short-duration SFR indicators (e.g. Hα), highlighting recent changes to SF in these galaxies, which are likely to be induced by the interaction. We propose a scenario where the lower mass galaxy has its SF suppressed by gas heating or stripping, while the higher mass galaxy has its SF enhanced, potentially by tidal gas turbulence and shocks. This is consistent with the seemingly contradictory observations for both SF suppression and enhancement in close pairs.
TL;DR: In this paper, shape-stabilized phase change materials composed of lauric acid and mesoporous silica with a high heat of fusion through evaporative solution impregnation are employed.
Abstract: The high variability and low heat of fusion of composite shape-stabilized phase change materials is a considerable challenge to their widespread application. Here, we present the synthesis of shape-stabilized phase change materials composed of lauric acid and mesoporous silica with a high heat of fusion through evaporative solution impregnation. Two hexagonal ordered silica with 2.8 and 6.3 nm pores (MCM-41, SBA-15) and two disordered mesocellular foams with 27–34.9 nm spherical pores connected by 10.4–14.9 nm windows are employed. The thermal properties and stability, heat storage efficiency, crystallization, and textural and chemical properties are investigated using differential scanning calorimetry (DSC) analysis, small- and wide-angle X-ray diffraction (XRD), nitrogen adsorption–desorption isotherms, and optical and electron microscopy, as well as Fourier transform infrared (FTIR) spectroscopy. Mesocellular foam silica (MCF)-based materials with up to 83% wt fatty acid show large latent heat (124 J g...
TL;DR: In this article, a 55,000 year discontinuous sequence (c.55,000-35,000; 13,000−0 cal. yr bp) of the Transylvanian forest steppe was analyzed.
Abstract: Aim The forest steppe of the Transylvanian Plain is a landscape of exceptionally diverse steppe-like and semi-natural grasslands. Is this vegetation a remnant of a
once continuous temperate forest extensively cleared by humans, or has the area, since the last glacial, always been a forest steppe? Understanding the processes that
drive temperate grassland formation is important because effective management of this biome is critical to the conservation of the European cultural landscape.
Location Lake Stiucii, north-western Romania, central-eastern Europe.
Methods We analysed multi-proxy variables(pollen, coprophilous fungi,plant macroremains, macrocharcoal) from a 55,000 year discontinuous sequence (c. 55,000–35,000; 13,000–0 cal. yr bp), integrating models of pollenbased
vegetation cover, biome reconstruction, global atmospheric simulations and archaeological records.
Results Needleleaf woodland occurred during glacial Marine Isotope Stage (MIS) 3, but contracted at the end of this period. Forest coverage of c. 55% (early Holocene) and 65% (mid-Holocene) prevailed through the Holocene, but Bronze Age humans extensively cleared forests after 3700 cal. yr bp. Forest coverage was most widespread between 8600 and 3700 cal. yr bp, whereas grasses, steppe and xerothermic forbs were most extensive between 11,700 and 8600 cal. yr bp and during the last 3700 cal. yr bp. Cerealia pollen indicate the presence of arable agriculture by c. 7000 cal. yr bp.
Main conclusions We have provided the first unequivocal evidence for needleleaf woodland during glacial MIS 3 in this region. Extensive forests prevailed prior to 3700 cal. yr bp, challenging the hypothesis that the Transylvanian lowlands were never wooded following the last glaciation. However, these forests were never fully closed either, reflecting dry growing season conditions, recurrent fires and anthropogenic impacts, which have favoured grassland persistence throughout the Holocene. The longevity of natural and semi-natural grasslands in the region may explain their current exceptional biodiversity. This longer-term perspective implies that future climatic warming and associated fire will maintain these grasslands.
TL;DR: In this paper, the authors show equipment developed in different research centers and universities to analyze thermophysical properties, such as specific heat, latent heat and melting temperature, and thermal conductivity and diffusivity of PCM and hybrid PCM materials.
Abstract: The use of thermal energy storage by phase change materials (PCM) is increasing in interest for building applications. For the deployment of the technology, appropriate characterization of PCM and hybrid PCM is essential, but it is not always possible to carry it out with conventional equipment, mainly due to the sample size. This paper shows equipment developed in different research centers and universities to analyze thermophysical properties, such as specific heat, latent heat and melting temperature, and thermal conductivity and diffusivity of PCM and hybrid PCM materials.
TL;DR: The results showed that both, pullulan and 6-carboxypullulan could be successfully used as reducing as well as capping agents for the AgNPs synthesis which shows potential antimicrobial activity against Gram positive and Gram negative bacteria.
TL;DR: In this paper, it was shown that the regularity of binomial edge ideal JG coincides with inlex(JG) and can be expressed in terms of the combinatorial data of G.
Abstract: We study the regularity of binomial edge ideals. For a closed graph G we show that the regularity of the binomial edge ideal JG coincides with the regularity of inlex(JG) and can be expressed in terms of the combinatorial data of G. In addition, we give positive answers to Matsuda-Murai conjecture (8) for some classes of graphs.
TL;DR: The use of the [Fe(III) (AA)(CN)4](-) complex anion as metalloligand towards the preformed [Cu(II) (valpn)Ln(III)](3+) or [Ni(II)-Ln (III) ](3%) heterometallic complex cations allowed the preparation of two families of heterotrimetallic complexes.
Abstract: The use of the [Fe(III) (AA)(CN)4](-) complex anion as metalloligand towards the preformed [Cu(II) (valpn)Ln(III)](3+) or [Ni(II) (valpn)Ln(III) ](3+) heterometallic complex cations (AA=2,2'-bipyridine (bipy) and 1,10-phenathroline (phen); H2 valpn=1,3-propanediyl-bis(2-iminomethylene-6-methoxyphenol)) allowed the preparation of two families of heterotrimetallic complexes: three isostructural 1D coordination polymers of general formula {[Cu(II) (valpn)Ln(III) (H2O)3 (μ-NC)2 Fe(III) (phen)(CN)2 {(μ-NC)Fe(III) (phen)(CN)3}]NO3 ⋅7 H2O}n (Ln=Gd (1), Tb (2), and Dy (3)) and the trinuclear complex [Cu(II) (valpn)La(III) (OH2 )3 (O2 NO)(μ-NC)Fe(III) (phen)(CN)3 ]⋅NO3 ⋅H2O⋅CH3 CN (4) were obtained with the [Cu(II) (valpn)Ln(III)](3+) assembling unit, whereas three isostructural heterotrimetallic 2D networks, {[Ni(II) (valpn)Ln(III) (ONO2 )2 (H2 O)(μ-NC)3 Fe(III) (bipy)(CN)]⋅2 H2 O⋅2 CH3 CN}n (Ln=Gd (5), Tb (6), and Dy (7)) resulted with the related [Ni(II) (valpn)Ln(III) ](3+) precursor. The crystal structure of compound 4 consists of discrete heterotrimetallic complex cations, [Cu(II) (valpn)La(III) (OH2)3 (O2 NO)(μ-NC)Fe(III) (phen)(CN)3 ](+), nitrate counterions, and non-coordinate water and acetonitrile molecules. The heteroleptic {Fe(III) (bipy)(CN)4} moiety in 5-7 acts as a tris-monodentate ligand towards three {Ni(II) (valpn)Ln(III)} binuclear nodes leading to heterotrimetallic 2D networks. The ferromagnetic interaction through the diphenoxo bridge in the Cu(II)-Ln(III) (1-3) and Ni(II)-Ln(III) (5-7) units, as well as through the single cyanide bridge between the Fe(III) and either Ni(II) (5-7) or Cu(II) (4) account for the overall ferromagnetic behavior observed in 1-7. DFT-type calculations were performed to substantiate the magnetic interactions in 1, 4, and 5. Interestingly, compound 6 exhibits slow relaxation of the magnetization with maxima of the out-of-phase ac signals below 4.0 K in the lack of a dc field, the values of the pre-exponential factor (τo) and energy barrier (Ea ) through the Arrhenius equation being 2.0×10(-12) s and 29.1 cm(-1), respectively. In the case of 7, the ferromagnetic interactions through the double phenoxo (Ni(II)-Dy(III)) and single cyanide (Fe(III)-Ni(II)) pathways are masked by the depopulation of the Stark levels of the Dy(III) ion, this feature most likely accounting for the continuous decrease of χMT upon cooling observed for this last compound.
TL;DR: In this paper, it was shown that the commutator is stable in permutations endowed with the Hamming distance, that is, two permutations that almost commute are near two commuting permutations.
TL;DR: Two novel bidimensional coordination polymers resulted from the assembling of cobalt(II) ions by 1,3-bis(4-pyridyl)azulene, using either 4,4'-bipyridol or 1,2-bis (4,4-'bipy)ethylene as neutral spacers.
Abstract: Two novel bidimensional coordination polymers, [Co(azbbpy)(4,4′-bipy)0.5(DMF)(NCS)2]·MeOH (1) and [Co(azbbpy)(bpe)0.5(DMF)(NCS)2]·0.25H2O (2), resulted from the assembling of cobalt(II) ions by 1,3-bis(4-pyridyl)azulene, using either 4,4′-bipyridyl or 1,2-bis(4-pyridyl)ethylene as neutral spacers. The cobalt(II) nodes in 1 and 2 act as single-ion magnets (SIMs).
TL;DR: In this paper, a multi-proxy analysis was performed on ombrotrophic peat profiles from the Rodna Mountains (northern Romania) to establish a quantitative record of hydro-climatic changes.
Abstract: Proxy-based reconstructions of climate variability over the last millennium provide important insights for understanding current climate change within a long-term context. Past hydrological changes are particularly difficult to reconstruct, yet rainfall patterns and variability are among the most critical environmental variables. Ombrotrophic bogs, entirely dependent on water from precipitation and sensitive to changes in the balance between precipitation
and evapotranspiration, are highly suitable for such hydro-climate reconstructions. We present a multi-proxy analysis (testate amoebae, plant macrofossils, stable carbon isotopes in Sphagnum, pollen, spores and macroscopic charcoal) from an ombrotrophic peat profile from the Rodna Mountains (northern Romania) to establish a quantitative record of hydro-climatic changes. We identify five main stages: wet surface mire conditions between AD 800 and 1150 and AD 1800 and 1950, and drying of the mire surface between AD 1300 and 1450, AD 1550 and 1750 and AD 1950 and 2012. Our multi-proxy reconstructions suggest that conditions during the Medieval Climate Anomaly (MCA) period (AD 900–1150) were considerably wetter than today, while during most of the ‘Little Ice Age’ (LIA; AD 1500–1850), they were dry. Mire surface conditions in the Rodna Mountains have dried markedly over the last 40 years mainly as a result of anthropogenic climate change approaching the driest conditions seen over the last 1000 years. There is a marked difference between current hydro-climatic conditions (dry mire) and those of the MCA (wet mire). This implies that for the study region, the MCA cannot provide analogous climatic conditions to the contemporary situation. Our reconstructions are in partial agreement with water table estimates elsewhere in central and eastern Europe but generally contrast with those from NW Europe, especially during LIA. We suggest that these distinctive regional differences result from fluctuations in large-scale atmospheric circulation, which determine the relative influences of continental and oceanic air masses.
TL;DR: An artificial ion-channel formed by H-bonded stacks of crown-ethers, where K(+) cation conduction is highly preferred to Na(+ cations, which may be regarded as a biomimetic of the KcsA channel.
Abstract: The bacterial KcsA channel conducts K(+) cations at high rates while excluding Na(+) cations. Herein, we report an artificial ion-channel formed by H-bonded stacks of crown-ethers, where K(+) cation conduction is highly preferred to Na(+) cations. The macrocycles aligned along the central pore surround the K(+) cations in a similar manner to the water around the hydrated cation, compensating for the energetic cost of their dehydration. In contrast, the Na(+) cation does not fit the macrocyclic binding sites, so its dehydration is not completely compensated. The present highly K(+)-selective macrocyclic channel may be regarded as a biomimetic of the KcsA channel.
TL;DR: In this article, a new hybrid nanomaterial which integrates the antibacterial and physico-chemical properties of silver nanoparticles, graphene oxide and chitosan biopolymer is presented.
07 Jun 2015
TL;DR: This work focuses on the problem of semantic segmentation based on RGB-D data, with emphasis on analyzing cluttered indoor scenes containing many visual categories and instances, based on a parametric figureground intensity and depth-constrained proposal process followed by a sequential inference algorithm that produces a complete scene estimate.
Abstract: We focus on the problem of semantic segmentation based on RGB-D data, with emphasis on analyzing cluttered indoor scenes containing many visual categories and instances. Our approach is based on a parametric figureground intensity and depth-constrained proposal process that generates spatial layout hypotheses at multiple locations and scales in the image followed by a sequential inference algorithm that produces a complete scene estimate. Our contributions can be summarized as follows: (1) a generalization of parametric max flow figure-ground proposal methodology to take advantage of intensity and depth information, in order to systematically and efficiently generate the breakpoints of an underlying spatial model in polynomial time, (2) new region description methods based on second-order pooling over multiple features constructed using both intensity and depth channels, (3) a principled search-based structured prediction inference and learning process that resolves conflicts in overlapping spatial partitions and selects regions sequentially towards complete scene estimates, and (4) extensive evaluation of the impact of depth, as well as the effectiveness of a large number of descriptors, both pre-designed and automatically obtained using deep learning, in a difficult RGB-D semantic segmentation problem with 92 classes. We report state of the art results in the challenging NYU Depth Dataset V2 [44], extended for the RMRC 2013 and RMRC 2014 Indoor Segmentation Challenges, where currently the proposed model ranks first. Moreover, we show that by combining second-order and deep learning features, over 15% relative accuracy improvements can be additionally achieved. In a scene classification benchmark, our methodology further improves the state of the art by 24%.
TL;DR: The increase of international trade over the years has been a result of the globalization process as mentioned in this paper, which refers to the interdependence between countries arising from the integration of different aspects of the economy, such as trade.
Abstract: International trade has an important share in GDP in different countries. Various companies from different countries are looking for new growth opportunities beyond their home country borders. Due to international trade, important sectors of the economies can be stimulated, such as transport and ICT sectors. Thus, international trade can be important for business, due to profits growth prospects, reduced dependence on known markets, business expansion, etc. The increase of international trade over the years has been a result of the globalization process. Thus, both consumers and companies can now choose from a wider range of products and services. Also, globalization refers to the interdependence between countries arising from the integration of different aspects of the economy, such as trade. International trade can stimulate economic growth of countries that are now so interconnected. Currently, globalization cannot be ignored by businesses, due to the opportunities offered by foreign markets.