A nonstandard definition of finite order ultradistributions

Taking into account that finite-order ultradistributions are inverse Fourier transforms of finite-order distributions a nonstandard representation is obtained for one-dimensional finite-order ultradistributions.     

Inexact Multi-Objective Local Search Proximal Algorithms: Application to Group Dynamic and Distributive Justice Problems

We introduce and examine an inexact multi-objective proximal method with a proximal distance as the perturbation term. Our algorithm utilizes a local search descent process that eventually reaches a weak Pareto optimum of a multi-objective function, whose components are the maxima of continuously differentiable functions. Our algorithm gives a new formulation and resolution of the following important distributive justice problem in the context of group dynamics: In each period, if a group creates a cake, the problem is, for each member, to get a high enough share of this cake; if this is not possible, then it is better to quit, breaking the stability of the group.     

Optimal Upper Estimates for the First Eigenvalue of a Jacobi Type Operator in Spherical and Hyperbolical Spaces

In this paper, our aim is to establish optimal upper estimates for the first positive eigenvalue of a Jacobi type operator, which is a suitable extension of the linearized operators of the higher order mean curvatures of a closed hypersurface immersed either in spherical or in hyperbolical spaces.     

Possible observation of cycloidal electromagnons in BiFeO3

We unravel the magnon spectra of BiFeO3 by means of low-energy inelastic light scattering. We show the existence of two species of magnons corresponding to spin wave excitations in and out of the cycloidal plane. These excitations might be interpreted as electromagnon modes. The present observations present an unique opportunity to study the competition between ferroelectric and magnetic orders.     

Kauffman Cellular Automata on Quasicrystal Topology

In this paper, we perform numerical simulations to study Kauffman cellular automata (KCA) on quasiperiod lattices. In particular, we investigate phase transition, magnetic entropy, and propagation speed of the damage on these lattices. Both the critical threshold parameter \(p_{c}\) and the critical exponents are estimated with good precision. In order to investigate the increase of statistical fluctuations and the onset of chaos in the critical region of the model, we have also defined a magnetic entropy to these systems. It is seen that the magnetic entropy behaves in a different way when one passes from the frozen regime (p < p_c) to the chaotic regime (p > p_c). For a further analysis, the robustness of the propagation of failures is checked by introducing a quenched site dilution probability q on the lattices. It is seen that the damage spreading is quite sensitive when a small fraction of the lattice sites are disconnected. A finite-size scaling analysis is employed to estimate the critical exponents. From these numerical estimates, we claim that on both pure (q =?0) and diluted (q =?0.05) quasiperiodic lattices, the KCA model belongs to the same universality class than on square lattices. Furthermore, with the aim of comparing the dynamical behavior between periodic and quasiperiodic systems, the propagation speed of the damage is also calculated for the square lattice assuming the same conditions. It is found that on square lattices the propagation speed of the damage obeys a power law as \(v\sim (p-p_{c})^{\alpha }\), whereas on quasiperiod lattices, it follows a logarithmic law as \(v \sim \ln (p-p_{c})^{\alpha }\).     

Observation of a Griffiths-like phase in the magnetocaloric compound Tb5Si2Ge2

The onset of a Griffiths-like phase has been observed in Tb5Si2Ge2 (TC=110 K) by means of magnetic susceptibility and small-angle neutron scattering experiments. We show the growth of a ferromagnetic cluster system characterized by an inverse susceptibility exponent lower than unity at TC相似文献   

Interference of Different Types of Mastication on Static Balance in Individuals without Temporomandibular Disorder

Purpose: This study was to determine whether non-habitual (isotonic) bilateral and unilateral mastication with eyes open and eyes closed exerts an influence on static balance in individuals without temporomandibular disorder (TMD). Method: An observational, cross-sectional study was conducted involving 20 volunteers aged 20 to 40 years without temporomandibular disorder. Static balance was assessed with the individuals in a quiet standing position on a force plate performing different types of mastication under six separate conditions. Results: Significant differences (p < .05) were found in the area of oscillation during bilateral mastication (eyes open) and the right unilateral mastication, significant differences were only found for oscillation area with eyes open and mediolateral center of pressure with eyes closed (p < .05). Conclusions: The findings of the present study reveal that the stomatognathic system (bilateral and unilateral mastication) promote changes in some variables of static balance.     

Thermodynamics properties of an anisotropic Ising antiferromagnet in both external longitudinal and transverse fields

We have studied the anisotropic two-dimensional nearest-neighbor Ising model with competitive interactions in both uniform longitudinal field H$H$ and transverse magnetic field Ω$\Omega$. Using the effective-field theory (EFT) with correlation in cluster with N=1$N=1$ spin we calculate the thermodynamic properties as a function of temperature with values H$H$ and Ω$\Omega$ fixed. The model consists of ferromagnetic interaction _Jx$J_x$ in the x$x$ direction and antiferromagnetic interaction _Jy$J_y$ in the y$y$ direction, and it is found that for H/_Jy∈[0,2]$H/J_y\in [0,2]$ the system exhibits a second-order phase transition. The thermodynamic properties are obtained for the particular case of λ=_Jx/_Jy=1$\lambda =J_x/J_y=1$ (isotropic square lattice).     

An ultrasonic-accelerated oxidation method for determining the oxidative stability of biodiesel

Biodiesel is considered an alternative energy because it is produced from fats and vegetable oils by means of transesterification. Furthermore, it consists of fatty acid alkyl esters (FAAS) which have a great influence on biodiesel fuel properties and in the storage lifetime of biodiesel itself. The biodiesel storage stability is directly related to the oxidative stability parameter (Induction Time – IT) which is determined by means of the Rancimat® method. This method uses condutimetric monitoring and induces the degradation of FAAS by heating the sample at a constant temperature. The European Committee for Standardization established a standard (EN 14214) to determine the oxidative stability of biodiesel, which requires it to reach a minimum induction period of 6 h as tested by Rancimat® method at 110 °C. In this research, we aimed at developing a fast and simple alternative method to determine the induction time (IT) based on the FAAS ultrasonic-accelerated oxidation. The sonodegradation of biodiesel samples was induced by means of an ultrasonic homogenizer fitted with an immersible horn at 480 Watts of power and 20 duty cycles. The UV–Vis spectrometry was used to monitor the FAAS sonodegradation by measuring the absorbance at 270 nm every 2. Biodiesel samples from different feedstock were studied in this work. In all cases, IT was established as the inflection point of the absorbance versus time curve. The induction time values of all biodiesel samples determined using the proposed method was in accordance with those measured through the Rancimat® reference method by showing a R² = 0.998.     

An unusual dimeric structure of a Cu(I) bis(thiosemicarbazone) complex: implications for the mechanism of hypoxic selectivity of the Cu(II) derivatives

The electrochemical reduction of Cu(II) bis(thiosemicarbazone) complexes [Cu(II)(btsc)] is accompanied by protonation to give an unstable Cu(I) intermediate [Cu(btscH(2))](+). The nature of this intermediate was probed by reaction of bis(thiosemicarbazone) ligands with a Cu(I) precursor which gave a novel helical dimeric dicationic complex. The dependence of these reactions on the ligand backbone substituents is discussed together with their possible relevance to the use of Cu(II) bis(thiosemicarbazone) ligands as hypoxic selective imaging and therapeutic agents.