University of Seville

About: University of Seville is a education organization based out in Seville, Andalucía, Spain. It is known for research contribution in the topics: Population & Model predictive control. The organization has 20098 authors who have published 47317 publications receiving 947007 citations. The organization is also known as: Universidad de Sevilla.

Aspiration of biological viscoelastic drops.

Abstract: Spherical cellular aggregates are in vitro systems to study the physical and biophysical properties of tissues. We present a novel approach to characterize the mechanical properties of cellular aggregates using a micropipette aspiration technique. We observe an aspiration in two distinct regimes: a fast elastic deformation followed by a viscous flow. We develop a model based on this viscoelastic behavior to deduce the surface tension, viscosity, and elastic modulus. A major result is the increase of the surface tension with the applied force, interpreted as an effect of cellular mechanosensing.

A review and classification of heuristics for permutation flow-shop scheduling with makespan objective

Abstract: Makespan minimization in permutation flow-shop scheduling is an operations research topic that has been intensively addressed during the last 40 years. Since the problem is known to be NP-hard for ...

The relationship between entrepreneurial orientation and growth: The moderating role of family involvement

Abstract: Lumpkin and Dess [Lumpkin, G.T., and G.G. Dess. 1996. Clarifying the entrepreneurial orientation construct and linking it to performance. Academy of Management Review 21, no. 1: 135–72] established the basis of their research agenda on the relationship between Entrepreneurial Orientation (EO) and company performance. A wide range of research has incorporated different moderating variables and dimensions of performance, such as profitability, growth, etc. Our work proposes the degree of family involvement comprising a moderating variable in the relationship between EO and company growth. This paper pursues to analyse the influence of family involvement on the relationship between EO and company growth. The empirical study was developed using a sample of 449 small- and medium-sized companies in Spain. The proposed hypotheses were tested using hierarchical linear regression. The results obtained reveal the influence of innovativeness and proactiveness on the growth of a company. However, when family involvem...

Liquid crystal phase diagram of the Gay-Berne fluid

Abstract: In this paper we report computer simulation results for bulk Gay-Berne fluids with anisotropy parameters κ = 3 and κ′ = 5. Using molecular dynamics simulations in the NVT ensemble, we identify isotropic fluid, nematic and smectic B phases. We observe that the nematic phase is only stable for reduced temperatures T* > 0·80. At lower temperatures, the isotropic phase directly evolves to the smectic B phase via a first order transition. We also give evidence of a weakly first order transition which involves a tilt of the molecular orientations with respect to the smectic planes. The effect of the attractive anisotropic forces in stabilizing the orientationally ordered phases is also studied by performing simulations for a WCA-type Gay-Berne fluid. When combined with previous studies of the vapour-liquid transition by Gibbs ensemble Monte Carlo simulations, and of the isotropic-nematic transition by thermodynamic integration, the results presented here provide quite a complete picture of the phase diagram for...

Soil restoration using composted plant residues: Effects on soil properties

Abstract: Organic soil amendments are increasingly being examined for their potential for soil restoration. In this paper, different composted plant residues consisting of leguminous (red clover, Trifolium pratense L.) (TP) and non-leguminous (rapeseed, Brassica napus L.) (BN) plants and the combination of both plant residues (red clover + rapeseed, Trifolium pratense L. + Brassica napus L. at a ratio 1:1) (TP + BN) were applied during a period of 4 years for restoring a Xelloric Calciorthid soil located near Seville (Guadalquivir Valley, Andalusia, Spain). The effect of the organic soil amendments on plant cover, soil physical (structural stability, bulk density), chemical (C/N ratio), and biological properties (microbial biomass, soil respiration and enzymatic activities (dehydrogenase, urease, β-glucosidase, phosphatase and arylsulfatase activities)) were determined. Organic amendments were applied at rate of 7.2 and 14.4 t organic matter ha −1 . All composted plant residues had a positive effect on soil physical properties. At the end of the experimental period and at the high rate, soil structural stability was highest in the BN (28.3%) treatment, followed by the TP + BN (22.4%) and the TP (14.5%) treatments and then the control. Soil bulk density was higher in the BN (30.9%), followed by TP + BN (26.2%) and TP (16.1%) treatments with respect to the control. However, soil biological properties (biomass C and the enzymatic activities) were particularly improved by the TP + BN treatment, followed by TP, BN and the control. After 4 years, the percentage of plant cover increased 87.2% in the TP + BN amended soil with respect to the control, followed by TP (84.1%) and BN (83.8%). These differences were attributed to the different chemical composition of the composts applied to the soils and their mineralization, controlled by the soil C/N ratio. The application of TP + BN compost with a C/N ratio of 18, resulted a more favourable soil biological properties and plant cover than the application of TP (C/N ratio = 8.8) and BN (C/N ratio = 47.7) composts.