Linear bilevel programming with uncertain lower-level costs

We study a bilevel programming problem with linear data, whose lower-level objective is a random variable with a known distribution. We consider the case where this distribution is nonatomic, allowing to pose the problem of the leader as the optimization of his expected value. We prove that under suitable assumptions this formulation turns out to be piecewise affine over the so-called chamber complex of the feasible region (of the high-point relaxation). We propose two algorithmic approaches to solve general problems enjoying this last property. The first one is based on enumerating the vertices of the chamber complex and evaluating them. The second one is based on the fact that randomly drawn points of the domain should be in the interior of a full-dimensional chamber, where the problem (restricted to this chamber) can be reduced to a linear program

Analysis of professionals and family foster care on advantages and difficulties of visits between foster children and their biological families

Contact between a foster child and birth parents play an important role in relation to the foster child’s wellbeing. The main aim of this study is to give voice to social workers and foster families about contact visits. This research is part of a project financed by the regional government of Andalusia (Spain) (SEJ-7106) regarding contact visits in foster care. Two focus groups were organized, one with 8 social workers from four foster care agencies and another with 8 foster carers (4 were recruited through the Association of Foster Families in Andalusia and 4 through fostering agencies). Access to foster care agencies and foster families was obtained through the official Andalusian Child Protective Services (SPM). The focal groups were audio-recorded. Transcripts (of the two focus groups gave rise to primary documents for the hermeneutic unit under study. All this information was exported from an Excel database to the ATLAS.ti v7.0 software. The transcripts were examined using an inductive method of open coding in order to identify themes among participants’ responses. Results show that both groups agreed on the utility of visits to maintain the children’s attachment to their birth family, to bring a greater sense of continuity to the children’s life story, to enhance the psychological wellbeing of the foster children and to know the real situation of their birth family. In relation to the difficulties remarked in the course of the visits, one of the issues mentioned by both groups refers to a lack in the coordination among the social workers, the SPM and the foster families involved. The other issue brings together several complaints to the SPM, such as the fact of not providing information about taking decisions regarding the future of the child; the lack of support and preparation of the foster carers, the children and the birth families about visits; as well as the shortage of social workers and economic aids provided by the SPM. The conclusions of this study highlight the need to improve contact visits by developing intervention strategies targeted at all those involved (foster children, family foster care, birth family and social workers). These findings have important implications for practice.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Dissecting the role of the φ29 terminal protein DNA binding residues in viral DNA replication

Published by Oxford University Press on behalf of Nucleic Acids Research. Phage φ29 DNA replication takes place by a proteinpriming mechanism in which the viral DNA polymerase catalyses the covalent linkage of the initiating nucleotide to a specific serine residue of the terminal protein (TP). The N-terminal domain of the φ29 TP has been shown to bind to the host DNA in a sequence-independent manner and this binding is essential for the TP nucleoid localisation and for an efficient viral DNA replication in vivo. In the present work we have studied the involvement of the TP N-terminal domain residues responsible for DNA binding in the different stages of viral DNA replication by assaying the in vitro activity of purified TP N-terminal mutant proteins. The results show that mutation of TP residues involved in DNA binding affects the catalytic activity of the DNA polymerase in initiation, as the Km for the initiating nucleotide is increased when these mutant proteins are used as primers. Importantly, this initiation defect was relieved by using the φ29 double-stranded DNA binding protein p6 in the reaction, which decreased the Km of the DNA polymerase for dATP about 130-190 fold. Furthermore, the TP N-terminal domain was shown to be required both for a proper interaction with the DNA polymerase and for an efficient viral DNA amplification.Spanish Ministry of Economy and Competitiveness [BFU2011–23645] ; Consolider-Ingenio from the Spanish 2800 Nucleic Acids Research, 2015, Vol. 43, No. 5 Ministry of Science and Innovation [CSD2007–00015 to M.S.] ; Institutional grant from Fundación Ramón Areces to the Centro de Biología Molecular‘Severo Ochoa’. I.H. was holder of an FPU fellowship from the Spanish Ministry of Education. Funding for open access charge: Spanish Ministry of Economy and Competitiveness [BFU2011- 23645]Peer Reviewe

The voice of birth families to improve visits in foster care

In foster care, contact visits with birth families play an important role in relation to the child’s wellbeing, and they may impact on placement outcomes. However, the views of birth parents with respect to such visits have largely been unexplored. This research is part of a project financed by the regional government of Andalusia (SEJ-7106) regarding contact visits in foster care. This study aims to give voice to parents and gather their views about contact visits, including how they might be improved. Participants were 23 birth families who had contact visits with 35 children in non-kinship foster care. Semi-structured individual interviews were conducted in order to explore two key aspects: the parents’ opinions regarding the contact visits and the main areas they felt needed improving. The interviews were transcribed and the transcripts were examined using an inductive method of open coding to identify themes among participants’ responses. The main themes to emerge concerned their general view of contact visits and the organization of visits. The paper discusses the study’s implications of the findings for practice.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Local and medium range order influence on the magnetic behavior of sputtered Ga-Rich FeGa thin films

We have investigated the influence of the growth power on the structural properties of Fe100-xGax (x ca. 29) films sputtered in the ballistic regime in the oblique incidence. By means of different structural characterizations, mainly X-ray diffraction and X-ray absorption spectroscopy, we have reached a deeper understanding about the influence of the local and medium range order on the magnetic behavior of Ga-rich FeGa thin films. On the one hand, the increase of the growth power reduces the crystallite size (medium order) that promotes the decrease of the coercive field of the layers. On the other hand, the growth power also determines the local order as it controls the formation of the A2, B2, and D03 structural phases. The increase of the uniaxial in-plane magnetic anisotropy with growth power has been correlated with the enhancement of both Ga pairs and a tetragonal distortion. The results presented in this work give more evidence about the magnetic anisotropy sources in Ga-rich FeGa alloys, and therefore, it helps to understand how to achieve a better control of the magnetic properties in this family of alloys.This work has been financially supported through project MAT2015-66888-C3-3-R (MINECO/FEDER) and RTI2018-097895-B-C43 of the Spanish Ministry of Economy and Competitiveness and through PR26/16-3B-2 of Santander and Universidad Complutense de Madrid. We thank "CAI Difracción de rayos-X" of UCM for the X-ray diffractometry measurements and the "Instituto de Sistemas Optoelectrónicos y Microtecnología" (ISOM) for using its facilities. We also want to thank BM25-Spline, the Spanish CRG at ESRF for providing beamtime

A quantum model of Schwarzschild black hole evaporation

We construct a one-loop effective metric describing the evaporation phase of a Schwarzschild black hole in a spherically symmetric null-dust model. This is achieved by quantising the Vaidya solution and by chosing a time dependent quantum state. This state describes a black hole which is initially in thermal equilibrium and then the equilibrium is switched off, so that the black hole starts to evaporate, shrinking to a zero radius in a finite proper time. The naked singularity appears, and the Hawking flux diverges at the end-point. However, a static metric can be imposed in the future of the end-point. Although this end-state metric cannot be determined within our construction, we show that it cannot be a flat metric

Escalado piloto de una formulación de acrílico de alto impacto utilizado en la fabricación de bases de dentadura

RESUMEN : New Stetic es una empresa que ofrece soluciones integrales odontológicas y médico-quirúrgicas para el cuidado de la salud. Dentro de sus líneas de producción y comercialización se encuentran los dientes acrílicos, resinas acrílicas, anestésicos, aleaciones, algodones, entre otros productos. Una de sus líneas más fuertes se encuentra concentrada en la producción, la investigación y el desarrollo de nuevas resinas acrílicas que permitan ser competitivas y ofrezcan beneficios innovadores para los consumidores. Dentro de estas resinas acrílicas se encuentra el acrílico de alto impacto, el cual es una de los productos con mayor importancia en la empresa gracias al beneficio económico que genera su venta y distribución (New Stetic, n.d.). Mediante la formulación del acrílico de alto impacto se pretende mejorar sus propiedades mecánicas como lo es la tenacidad de fractura, utilizando modificadores conformados principalmente por caucho que conlleven a la obtención de un producto de alta calidad y que traiga beneficios económicos para la empresa. Previo a este trabajo se hicieron reacciones a escala laboratorio en donde se determinó que el uso de modificadores como M-211 y DLM mejoran las propiedades mecánicas del acrílico de alto impacto, con lo que se procedió a un escalado piloto en donde se observó que el modificador que favorece en gran medida dichas propiedades es el M-211. Además de eso, se logró comprobar que utilizar PVA en las proporciones adecuadas durante la solvatación y el medio de suspensión ayuda a mejorar el tamaño de partícula, así como la estabilidad de la reacción

Caracterización molecular y funcional de genes que codifican proteínas de choque térmico (OpsHSP18, AtDjA2 y AtDjA3) de plantas bajo estrés abiótico

"El estrés abiótico es la principal causa de pérdidas de cultivos en el mundo. Sin embargo, las plantas han desarrollado mecanismos que les permiten detectar, responder y tolerar a múltiples estreses. Uno de los principales mecanismos de tolerancia al estrés en plantas, es la síntesis de proteínas de choque térmico (HSP). En este trabajo se llevó a cabo la caracterización funcional del gen OpsHSP18 de nopal (Opuntia streptacantha) que codifica una HSP de bajo peso molecular (sHSP), el cual se aisló de una biblioteca de cDNA de nopal. Líneas transgénicas de Arabidopsis thaliana que sobreexpresan el gen OpsHSP18 mostraron un mayor porcentaje de germinación bajo estrés salino (NaCl) y osmótico (glucosa y manitol) y bajo la aplicación de ABA, en comparación con la WT (Col-0). Asimismo, en ensayos de tolerancia al estrés por la aplicación de NaCl o glucosa, las líneas 35S::OpsHSP18, mostraron un aumento en el porcentaje de supervivencia con respecto a Col-0. Por otro lado, en esta tesis nos enfocamos a estudiar los genes AtDjA2 y AtDjA3 de Arabidopsis que codifican para proteínas J (HSP40). Para su caracterización se obtuvieron líneas mutantes de T-DNA y se generaron líneas sobreexpresantes para ambos genes. Respecto al gen AtDjA3, se han reportado dos transcritos: el AtDjA3.1 (343 aa) y AtDjA3.2 (420 aa). La línea mutante del gen AtDjA3 mostró un fenotipo de sensibilidad a estrés salino, osmótico y tratamientos de ABA, mientras que las líneas que sobreexpresan la versión AtDjA3.2, mostraron una mayor tasa de germinación, mayor desarrollo de los cotiledones y peso fresco de las plántulas sometidas a estrés. También generamos líneas sobreexpresantes de la versión AtDJA3.1 de Arabidopsis, para su posterior análisis. En lo que respecta al gen AtDjA2, la línea mutante (j2) mostró un retraso en la germinación bajo los tratamientos de glucosa y ABA, caso contrario a lo observado en las líneas transgénicas. Este comportamiento fue también observado en el desarrollo de los cotiledones bajo la aplicación de NaCl y glucosa. Por último, con la finalidad de identificar proteínas blanco y/o interactores de las proteínas HSP, se construyeron vectores anzuelo para levadura pDHB1/OpsHSP18 y pDHB1/AtDJA2, que se utilizarán en el sistema de dos híbridos “Split ubiquitin”. Los resultados indican que ambas chaperonas de la familia HSP están involucradas en la respuesta al estrés abiótico, y una posible relación de las proteínas HSP con la ruta de señalización de ABA.""Abiotic stress is the main cause of crop loss worldwide. However, plants have developed mechanisms that allow them to detect, respond to and tolerate multiple stresses. It has been reported that in plants the synthesis of heat shock proteins (HSP) is one of the main mechanisms of stress tolerance. In this work was performed the functional characterization of OpsHSP18 gene of cactus (Opuntia streptacantha) encoding a low molecular weight HSP (sHSP). This gene was isolated from a cactus cDNA library under abiotic stress. A. thaliana 35S::OpsHSP18 over-expressing lines showed a higher germination percentage under ABA application, salt (NaCl), and osmotic (glucose and mannitol) stress, compared to the WT (Col-0). Also, wasobserved an increase in the survival rate of over-expressing plants during the application of NaCl and glucose. Moreover, from a subtractive library (SHS) of bean (Phaseolus vulgaris) under salt stress it was isolated the unigen SSHPv-S38, which encodes the protein J (HSP40). In order to characterize the AtDjA3 and AtDjA2 orthologous genes from A. thaliana, we obtained over-expressing and T-DNA lines of these genes. It is known that AtDjA3 gene produce two transcript: AtDjA3.1 (343 aa) and AtDjA3.2 (420 aa). It was observed a sensitive phenotype during abiotic stress in mutant plants of the AtDjA3 gene in compared to Col-0. The 35S::AtDjA3.2 overexpressing lines showed a tolerance under salt and osmotic stress, and ABA application. The tolerance phenotype was measured by the increase of germination percentage, cotyledons development and fresh weight of seedlings. To date, we have over-expressing lines of the version AtDjA3.1 from Arabidopsis, this line will be analyzed under abiotic stress. Regarding AtDjA2 gene, it was observed a delay in germination percentage under glucose or ABA application in the mutant line of the AtDjA2 gene, whereas, an increase in germination percentage was observed in transgenic lines. Additionally, in the 35S::AtDjA2 transgenic lines, a higher percentage of green cotyledons development was observed under application of NaCl and glucose. In order to identify possible interactors of HSP proteins, we generate bait vectors pDHB1/AtDJA2 and pDHB1/OpsHSP18, for the "Split ubiquitin" two-hybrid system in Saccharomyces cerevisiae. From the results obtained during this study, both molecular chaperones of the HSP family are involved in the response abiotic stress; and hormone ABA.

Estudio de factibilidad para la aplicación de un proyecto de aguas grises en la ciudad de Parral

90 p.De acuerdo a parámetros internacionales Chile presenta escasez hídrica en gran parte de su territorio, y la demanda por este recurso sigue en aumento. El presente trabajo de titulo tiene como objetivo principal aportar una herramienta para mejorar la eficiencia del uso del agua potable en la ciudad de Parral,introduciendo el tema de reutilización de aguas grises como un medio para disminuir la demanda de agua. Este trabajo contiene una primera parte basada en investigación de diversos estudios nacionales e internacionales de temas como caracterización de aguas, tratamientos, usos de aguas reutilizadas, marco legal y experiencias en Chile y el extranjero de sistemas de reutilización de aguas grises. Posteriormente se realiza una caracterización del lugar de estudio, la ciudad de Parral ubicada en la VII región del Maule con el fin de conocer y determinar el medio físico, social y natural de la zona a estudiar. El capitulo siguiente corresponde al desarrollo del proyecto, y mediante una metodología establecida se determinan los volúmenes de aguas grises a obtener según tipo de cliente, para una muestra representativa de la ciudad. De este análisis se obtiene que alrededor del 40% del agua de una vivienda es factible reutilizarla en usos como riego o recarga de inodoros. Finalmente el análisis económico de costos versus beneficios establece que para el caso viviendas de familias grandes y medianas el costo de inversión generado por la instalación de un sistema para reutilizar las aguas grises es posible recuperarlo en un tiempo de 2 a 4 años, mediante el ahorro en consumo de agua potable que se generará como consecuencia a la reutilización de agua./SUMMARY: In accordance with international parameters, Chile exhibits a water shortage supply in most part of the territory, and yet there is an increasing demand for this resource.The present professional degree thesis has as its main objective to contribute with a useful tool to improve the efficiency of the use of drinking water in the city of Parral, introducing the topic of re-utilization of current waters as a means to diminish the demand for water. This work consists of a main part based on research of various national and international studies of such issues as the characterization and treatment of the waters, uses of re-utilised waters, legal framework and experiences in Chile and abroad of the systems of re-utilization of current waters. Next, a characterization of the locus of study, the city of Parral located in the 7th Region, Maule Region, is given with the purpose of getting to know and determine the physical, social and natural environment of the area under study.The following chapter corresponds to the development of the Project, and by means of a methodology previously established the volumes of current waters to be obtained are determined according to the type of customer, for a representative sample of the city. From this analysis, it is possible to estimate that about 40% of the water of a home is feasible to be re-utilized in uses such as irrigation or refilling of the toilets. Finally, the cost/ benefit analysis establishes that in case of large and medium size family homes the cost of investment generated for the installation of a system to re-utilize the current waters can be recovered within 2 to 4 years, by means of the savings in the consumption of drinking water generated as a consequence of the re-utilization of water

Local and medium range order influence on the magnetic behavior of sputtered ga-rich fega thin films

We have investigated the influence of the growth power on the structural properties of Fe_100_(-x)Ga_x (x ca. 29) films sputtered in the ballistic regime in the oblique incidence. By means of different structural characterizations, mainly X-ray diffraction and X-ray absorption spectroscopy, we have reached a deeper understanding about the influence of the local and medium range order on the magnetic behavior of Ga-rich FeGa thin films. On the one hand, the increase of the growth power reduces the crystallite size (medium order) that promotes the decrease of the coercive field of the layers. On the other hand, the growth power also determines the local order as it controls the formation of the A2, B2, and D0_3 structural phases. The increase of the uniaxial in-plane magnetic anisotropy with growth power has been correlated with the enhancement of both Ga pairs and a tetragonal distortion. The results presented in this work give more evidence about the magnetic anisotropy sources in Ga-rich FeGa alloys, and therefore, it helps to understand how to achieve a better control of the magnetic properties in this family of alloys