Search results for "Stability."
showing 10 items of 3015 documents
M14_Microfluidics_for_CNT
2018
The CNT dispersion with low SDBS content allows stable droplet formation but leads to fast formation of CNT plugs in the hydrophobic channels. The selective channel surface treatment allows long-term stable functionality of the microfluidic system.
Discrete cortical representations and their stability in the presence of synaptic turnover
2015
Population imaging in mouse auditory cortex revealed clustering of neural responses to brief complex sounds: the activity of a local population typically falls close to one out of a small number of observed states [1]. These clusters appear to group sets of auditory stimuli into a discrete set of activity patterns and could thereby form the basis for representations of sound categories. However, to be useful for the brain, such representations should be robust against fluctuations in the underlying circuitry, which are significant even in the absences of any explicit learning paradigm [2]. Here we introduce a novel firing rate based circuit model of mouse auditory cortex to study the emerge…
The [Fe(etz)6](BF4)2 Spin-Crossover System—Part One: High-Spin ⇌ Low-Spin Transition in Two Lattice Sites
1996
The [Fe(etz),](BF,), spin-cross-over system (etz = 1-ethyl-1 H-tetrazole) crystallizes in space group P1, with the following lattice constants at 298 K: a 10.419(3), b=15.709(1), c = 18.890(2) A = = 71.223(9), =77.986(10), and = 84.62(1)° V = 2862.0(9) A3 and Z = 3. Two nonequivalent lattice sites, one without (site A) and one with (site B) inversion symmetry, are observed. The population of the two sites nA:nB is 2:l. Iron(II) on site A undergoes a thermal low-spin (LS) high-spin (HS) transition with T1/2I, = 105 K. whereas that on site B remains in the high-spin state down to cryogenic temperatures. Application of external pressure of up to 1200 bar between 200 and 60 K does not cause for…
Lifetime measurements of the 3D3/2 and 3D5/2 metastable states in CaII
1993
The lifetime of the metastable 3D3/2 and 3D5/2 states of Ca+ ions is determined in a r.f. ion trap by laser excitation of this levels and subsequent time delayed probing of the state population by a second laser. In a buffer gas atmosphere of about 10−5−10−6 mbar of He we observe quenching to the ground state and strong finestructure mixing of the two D-states. This mixing allowes only the determination of the combined lifetime. Our result of τ(3D)=1.24(39) s is in good agreement with theoretical calculations.
Energy transfer in diiodoBodipy-grafted upconversion nanohybrids.
2015
Steady-state and time-resolved emission studies on nanohybrids consisting of NaYF4:Yb,Er and a diiodo-substituted Bodipy (UCNP-IBDP) show that the Yb(3+) metastable state, formed after absorption of a near-infrared (NIR) photon, can decay via two competitive energy transfer processes: sensitization of IBDP after absorption of a second NIR photon and population of Er(3+) excited states.
On the qualitative analysis of the solutions of a mathematical model of social dynamics
2006
Abstract This work deals with a family of dynamical systems which were introduced in [M.L. Bertotti, M. Delitala, From discrete kinetic and stochastic game theory to modelling complex systems in applied sciences, Math. Models Methods Appl. Sci. 7 (2004) 1061–1084], modelling the evolution of a population of interacting individuals, distinguished by their social state. The existence of certain uniform distribution equilibria is proved and the asymptotic trend is investigated.
ON THE EXISTENCE OF LIMIT CYCLES IN OPINION FORMATION PROCESSES UNDER TIME PERIODIC INFLUENCE OF PERSUADERS
2008
This paper concerns a model of opinion formation in a population of interacting individuals under the influence of external leaders or persuaders, which act in a time periodic fashion. The model is formulated within a general framework inspired to a discrete generalized kinetic approach, which has been developed in Ref. 6. It is expressed by a system of non-autonomous nonlinear ordinary differential equations. The dynamics of such a system is investigated and the existence of a globally asymptotically stable periodic solution is analytically proved in three example cases, each one corresponding to a different quantitative choice of the actions of the persuaders. Equivalently, in three part…
Learning Curve in Surgical Treatment of Odontoid Fixation for a Series of Type II C2 Fractures
2019
The craniovertebral junction (CVJ) is a complex anatomical area upon which most of the motion of the upper cervical spine depends [1]. Because of its unique range of motion, the CVJ is subject to several types of traumatic injury; it has been shown that odontoid fractures are the most common ones in the general population and are the most common isolated spinal fractures [2]. Accounting for up to 18% of all cervical fractures, odontoid fractures are the most common ones in elderly patients [3], in whom they account for up to 60% of spinal cord injuries [4].
Considerations on the Advantages and Disadvantages of Romania's Accession to the European Union
2015
Abstract After nine years from Romania's accession to the European Union, the advantages are sustained with specific statistical markers, which could have been more positive if the effect of certain identified causes (reduced administrative ability, political instability, extended corruption, high tax evasion etc.) would have been diminished. Counterbalancing the benefits of the accession the opinion polls show the disadvantages. If a poll conducted four years prior to the accession showed that 66% of Romania's population considered that the accession to the European Union would produce positive effects, after six years from the accession things have reversed and 58% of Romanians considered…
Achievement perceived, parenting, internet use and adolescent behavior
2019
espanolResumen El uso intensivo de internet puede contribuir a desarrollar disfunciones psicosociales graves en la adolescencia. El objetivo de esta investigacion es analizar las relaciones de la percepcion de eficacia academica con el uso de internet para ocio, los estilos de crianza y los problemas exteriorizados e interiorizados en la adolescencia (agresividad proactiva, reactiva, fisica y verbal, afiliacion a pares rebeldes e inestabilidad emocional). Han participado 762 adolescentes de 12 a 17 anos (M = 13.69; DT = 1.40; varones 52.8%). Utilizan internet en tiempo de ocio entre cero y 98 horas semanales, de ahi que la poblacion se haya distribuido en cuartiles. Las variables se han obt…