Groundwater pollution in quaternary aquifer of Vitoria - Gasteiz (Basque Country, Spain)

As a result of diverse changes in land use and in water-resource management in the high basin of the Zadorra River (Basque Country), an important loss of water resources and an intense contamination by nitrogen compounds has taken place. The purpose of this paper is to detail the land transformations that have taken place on the aquifer since the 1950s: increase of drainage network, change from dry to irrigated farming, and diversion of rivers at the aquifer unit inlet. Furthermore, we analyze the impact of these transformations on the hydrodynamics and water quality of this aquifer system

Evenly convex sets, and evenly quasiconvex functions, revisited

Since its appearance, even convexity has become a remarkable notion in convex analysis. In the fifties, W. Fenchel introduced the evenly convex sets as those sets solving linear systems containing strict inequalities. Later on, in the eighties, evenly quasiconvex functions were introduced as those whose sublevel sets are evenly convex. The significance of even convexity relies on the different areas where it enjoys applications, ranging from convex optimization to microeconomics. In this paper, we review some of the main properties of evenly convex sets and evenly quasiconvex functions, provide further characterizations of evenly convex sets, and present some new results for evenly quasiconvex functions.This research has been partially supported by MINECO of Spain and ERDF of EU, Grants PGC2018-097960-B-C22 and ECO2016-77200-P

Editorial: New insights into adult neurogenesis and neurodegeneration: challenges for brain repair

The formation of new neurons in the brain is probably one of the most controversial topics in the scientific community since in the 1960's Joseph Altman described for the first time that proliferating cells give rise to new neurons in the adult brain of rats and other mammals. This Research Topic includes 1 brief research report, 3 mini review, 4 review and 9 original research papers gathering different contributions highlighting new developments in the field of neurogenesis

Robust solutions to multi-objective linear programs with uncertain data

In this paper we examine multi-objective linear programming problems in the face of data uncertainty both in the objective function and the constraints. First, we derive a formula for the radius of robust feasibility guaranteeing constraint feasibility for all possible scenarios within a specified uncertainty set under affine data parametrization. We then present numerically tractable optimality conditions for minmax robust weakly efficient solutions, i.e., the weakly efficient solutions of the robust counterpart. We also consider highly robust weakly efficient solutions, i.e., robust feasible solutions which are weakly efficient for any possible instance of the objective matrix within a specified uncertainty set, providing lower bounds for the radius of highly robust efficiency guaranteeing the existence of this type of solutions under affine and rank-1 objective data uncertainty. Finally, we provide numerically tractable optimality conditions for highly robust weakly efficient solutions.This research was partially supported by the Australian Research Council, Discovery Project DP120100467, the MICINN of Spain, grant number MTM2011-29064-C03-02, and Generalitat Valenciana, grant number ACOMP/2013/062

Robust Solutions of MultiObjective Linear Semi-Infinite Programs under Constraint Data Uncertainty

The multiobjective optimization model studied in this paper deals with simultaneous minimization of finitely many linear functions subject to an arbitrary number of uncertain linear constraints. We first provide a radius of robust feasibility guaranteeing the feasibility of the robust counterpart under affine data parametrization. We then establish dual characterizations of robust solutions of our model that are immunized against data uncertainty by way of characterizing corresponding solutions of robust counterpart of the model. Consequently, we present robust duality theorems relating the value of the robust model with the corresponding value of its dual problem.This research was partially supported by the Australian Research Council, Discovery Project DP120100467, the MICINN of Spain, grant MTM2011-29064-C03-02, and Generalitat Valenciana, grant ACOMP/2013/062

Guaranteeing highly robust weakly efficient solutions for uncertain multi-objective convex programs

This paper deals with uncertain multi-objective convex programming problems, where the data of the objective function or the constraints or both are allowed to be uncertain within specified uncertainty sets. We present sufficient conditions for the existence of highly robust weakly efficient solutions, that is, robust feasible solutions which are weakly efficient for any possible instance of the objective function within a specified uncertainty set. This is done by way of estimating the radius of highly robust weak efficiency under linearly distributed uncertainty of the objective functions. In the particular case of robust quadratic multi-objective programs, we show that these sufficient conditions can be expressed in terms of the original data of the problem, extending and improving the corresponding results in the literature for robust multi-objective linear programs under ball uncertainty.This research was partially supported by the Australian Research Council, Discovery Project DP120100467 and the MINECO of Spain and ERDF of EU, Grants MTM2014-59179-C2-1-P and ECO2016-77200-P

The radius of robust feasibility of uncertain mathematical programs: A Survey and recent developments

The radius of robust feasibility provides a numerical value for the largest possible uncertainty set that guarantees feasibility of a robust counterpart of a mathematical program with uncertain constraints. The objective of this review of the state-of-the-art in this field is to present this useful tool of robust optimization to its potential users and to avoid undesirable overlapping of research works on the topic as those we have recently detected. In this paper we overview the existing literature on the radius of robust feasibility in continuous and mixed-integer linearly constrained programs, linearly constrained semi-infinite programs, convexly constrained programs, and conic linearly constrained programs. We also analyze the connection between the radius of robust feasibility and the distance to ill-posedness for different types of uncertain mathematical programs.This research was partially supported by the Australian Research Council, Discovery Project grant and the Ministry of Science, Innovation and Universities of Spain and the European Regional Development Fund (ERDF) of the European Commission, Grant PGC2018-097960-B-C22

Unexpected dielectric response in lead zirconate titanate ceramics: The role of ferroelectric domain wall pinning effects

Temperature dependent dielectric response has been measured in Pb(Zr1-xTix)O-3 ceramics. Samples of different compositions (x=0.40, 0.47, and 0.60), pure and doped with Nb-or Fe, were studied at temperatures between 15 and 700 K and in the frequency range from 100 Hz to 1 MHz. Unexpected dielectric behavior has been found around room temperature. Anomalous temperature dependent permittivity is observed in pure and Fe-doped samples but not in Nb-doped samples. The anomaly appears related to the presence of oxygen vacancies but not on the sample crystallographic phase. The authors suggest that the anomaly may be a manifestation of the domain wall pinning effect. (C) 2007 American Institute of Physics.Peer ReviewedPostprint (published version

Tratamiento quirúrgico de fracturas toracolumbares por vía posterior con instrumentación y fusión bisegmentaria

Analizamos de forma retrospectiva, los resultados clínico-radiológicos y funcionales de pacientes con fracturas vertebrales con y sin afección neurológica, intervenidos quirúrgicamente mediante instrumentación vertebral pedicular de los dos segmentos adyacentes a la vértebra fracturada. Se estudian 30 pacientes que presentan fractura vertebral inestable del segmento toracolumbar, intervenidos desde enero de 1993 hasta diciembre de 2000. En todos los casos se realizó abordaje posterior, con inclusión en 8 casos de la vértebra fracturada y artrodesis posterolateral en todos los casos con injerto antólogo córtico-esponjoso. En dos casos con déficit neurológico se asoció laminectomía con descompresión posterolateral. El resultado clínico-funcional lo valoramos según la escala de Smiley-Webster con resultados excelentes en 22 pacientes. El índice sagital preoperatorio fue de 14,4 grados y postoperatorio de 4,2 grados. La altura media del cuerpo vertebral preoperatorio fue de 46% y postoperatoria de 78%. Los resultados obtenidos con esta fijación son similares a los obtenidos con otras técnicas, que requieren instrumentaciones y fusiones más largas o segundas intervenciones para retirar la fijación.We evaluate retrospectively the clinical, radiologic and functional outcomes of patients admitted to our hospital with unstable vertebral fractures with or without neurologic lesion treated with posterior fusion and transpedicular instrumentation of the upper and lower segment to the fractured vertebra. Thirty patients with unstable vertebral fracture of the thoracolumbar segment surgically managed between January 1993 and December 2000 are studied. The surgical approach was posterior in all cases, with posterolateral fusion with autologous corticocancellous graft. In 8 patients the fractured vertebra was also included. In two cases with neurologic impairment, a posterolateral decompression and laminectomy were associated. The Smiley-Webster score was used for the clinical and functional outcome with excellent results in 22 patients. The preoperative sagittal index was 14,4 degrees and improved to 4,2 degrees after surgery. The mean of vertebral body height was 46% preoperatively, and 78% postoperatively. The results obtained with this fixation are similar to other devices which require longer fusion and instrumentation or a second procedure to remove the hardware

Contribution of mangotoxin to the virulence and epiphytic fitness of Pseudomonas syringae pv. syringae

Mangotoxin is an antimetabolite toxin that inhibits ornithine acetyl transferase, a key enzyme in the biosynthetic pathway of ornithine and arginine and recently reported in strains of Pseudomonas syringae pv. syringae (Pss) isolated from mango. Since symptoms on mango tissues are very difficult to reproduce, in this study the role of mangotoxin in Pss virulence was addressed by analyzing the in planta growth and development of disease symptoms on tomato leaflets. Inoculation experiments were carried out following several procedures using the wild-type strain Pss UMAF0158, two Tn5-mutant derivative strains defective in mangotoxin production, and their complemented derivative strains in which mangotoxin production is restored. The ability of the mangotoxin-defective mutants to grow in planta was similar, and their epiphytic survival on the tomato leaf surface identical to the wild-type and complemented strains. However, both the disease index data of incidence and the severity of necrotic symptoms indicated that mangotoxin-defective mutants were less virulent, indicating that mangotoxin is a virulence factor. Furthermore, competition experiments showed that the survival values of the wild-type strain were slightly but significantly higher than those of the mangotoxin-defective mutants, suggesting that mangotoxin production would improve the epiphytic fitness of Pss. [Int Microbiol 2009; 12(2):87-95