http://hdl.handle.net/10171/5038 2013-05-20T14:33:31Z http://hdl.handle.net/10171/29156 Title: Breath Figures Formation Author(s) : Guadarrama-Cetina, J. (José) Abstract: We present experimental observations of Breath Figures (BF) which are formed by the dew of water when it condenses on a cold surface. The experiments were done in specific conditions and configurations of temperature, surfaces and mixes in controlled concentration of miscibles and immiscibles substances like the salt saturated solution, alcohol and silicon oil (C6H18O2Si). The hydrophobic surfaces used on those observations are thin glasses coated with ITO (Indium Tin Oxide), 3M ECG-1700 which is repellent to the silicon oil too, and silane which is hydrophobic. Those observations let us to perform direct geometrical measurements of the droplets like radii r, areas a and with the values of contact angle θ the volume V that form the Breath Figures. Other indirect measurements obtained from the direct measurements are the factor occupation ǫ2, the values of concentration of water once it has condensed over a cold surface t−1 c , and when it changes from liquid phase to solid phase and when the BF takes part in a process of deposition, also the fractal dimension of the BF pattern to characterize the geometrical properties in a liquid phase and solid phase. Once the average of direct measurements are obtained we extract laws of growth and the evolution of the phenomena a how outward factors modify the achievement of the process of condensation and what is the observable pattern result.--------------------------------------------------- Presentamos observaciones experimentales del fenómeno figuras de aliento (´o BF por Breath Figure) el cual se forma por el rocío de agua cuando esta condensa en una superficie fría. Se han hecho experimentos con condiciones y configuraciones específicas de temperatura, superficies y concentraciones de mezclas de sustancias miscibles e inmiscibles como una solución saturada de sal, alcohol y hexametildisiloxano (C6H18O2Si). Las superficies hidrofóbicas utilizadas en las observaciones son vidrios recubiertos con ´oxido titanio e indio, 3M ECG-1700 el cual es repelente al hexametildisiloxano también, así como el silano también tiene propiedades hidrofóbicas. Estas observaciones nos permiten llevar acabo mediciones directas de la geometría de gotas, como el radio r y el área a, ángulos de contacto θ y volúmenes V que forman los Breath Figures. Otras medidas indirectas son obtenidas de mediciones directas son el factor de ocupación ǫ2, los valores de concentración de agua una vez ha condensado sobre la superficie t−1 c , y cuando esta cambia de fase líquida a sólida y cuando el BF toma parte en el proceso de deposición, también la dimensión fractal de los patrones del BF que caracterizan sus propiedades geométricas en la fase líquida o sólida. Una vez que se ha obtenido el promedio de mediciones directas se extraen leyes de crecimiento y la evolución de los fenómenos y como factores externos modifican el desempeño del proceso y las observables del patrón resultante. 2012-12-31T23:00:00Z http://hdl.handle.net/10171/28205 Title: Quality and fitness-for-use assessments on ther primary data indexed at the Global Biodiversity Information Facility (GBIF) Author(s) : Otegui, J. (Javier) Abstract: Aunque la biodiversidad siempre ha sufrido diversas amenazas debido a su naturaleza dinámica, en las últimas décadas se ha llegado, principalmente por el efecto del creciente impacto humano en el medio ambiente, a un escenario que se conoce como la crisis de la biodiversidad, una crisis cuyo tratamiento, se dice, depende en buena medida de la ampliación del conocimiento sobre biodiversidad. Como parte fundamental de la solución para esta demanda de conocimiento, se crea la Infraestructura Global de Información de Biodiversidad (GBIF por sus siglas en inglés) con el fin de hacer disponibles de manera libre y universal los datos de biodiversidad a través de Internet. Hoy por hoy, GBIF representa la mayor red de instituciones editoras de datos primarios de biodiversidad (PBD). Sin embargo, se ha defendido progresivamente entre los implicados en el estudio de la biodiversidad la conveniencia de evaluar la calidad de los PBDs servidos a través de GBIF de manera que los proveedores dueños de la propiedad intelectual de los mismos sean conscientes del estado de los registros que comparten. En este marco se encuadra la presente Tesis Doctoral, que ha tenido como objetivo general contribuir al desarrollo de la informática aplicada a la biodiversidad. Esto se traduce en los siguientes objetivos particulares: (a) evaluar la calidad y usabilidad de los PBDs accesibles a través de la red de instituciones editoras de datos de GBIF; (b) analizar con mayor profundidad desde distintas perspectivas aspectos más detallados del conjunto de PBDs disponibles para generar recomendaciones de mejora; (c) facilitar a la comunidad el acceder a distintos análisis sencillos de calidad de datos mediante el desarrollo de una herramienta web de visualización de colecciones de PBDs; y (d) aplicar el conocimiento adquirido para realizar estudios ejemplares del uso de los datos disponibles en la red de GBIF. Los resultados muestran que, si bien, la compleción de los registros en general es buena, la distribución de sus componentes no lo es tanto, permitiendo detectar de la extracción de sus pautas el efecto low-hanging fruit (la sobrerrepresentación de los registros sencillos de obtener en relación a los más complicados). El gran volumen de datos disponibles no merma la necesidad de aumentar la información disponible, bien descubriendo a la red colecciones existentes o continuando con el muestreo de zonas de elevada biodiversidad con el fin de aumentar la usabilidad de la información. 2013-04-03T22:00:00Z http://hdl.handle.net/10171/28204 Title: Síntesis y caracterización de polímeros de ciclodextrina. Aplicación a la liberación de fármacos Author(s) : Machín, R. (Rubén) Abstract: Cyclodextrins (CD) are cyclic oligosaccharides which have been widely employed for pharmaceutical applications. CD based hydrogels have been synthesized by the crosslinking reaction with epichlorohydrin using αCD, ßCD, γCD, and 50:50 mixtures of α/ßCD and ß/γCD, at different synthesis temperatures. These gels have been characterized by measuring their swelling capacity, mechanical behavior, thermal properties and pore size distribution. The hydrogels synthesized at higher temperatures present a higher swelling capacity, due to the self-polymerization of epichlorohydrin, yielding a more expanded reticular structure with pores of higher diameter. Mechanical assays show that a lower synthesis temperature leads to stronger and harder polymers, according with a lower swelling capacity. Polymers containing different CD types and synthesized at the same temperature present similar reticular structures. In order to investigate the sorption capacity of these hydrogels toward different solutes, five model molecules have been selected: phenol, 3-nitrophenol, 4-nitrophenol, 1-naphthol, and the antiinflamatory drug diflunisal. The amounts sorbed have been related to the different affinities of CDs to the solutes. Drug delivery of two antiinflammatory (naproxen and nabumetone) and two antifungal drugs (naftifine and terbinafine) from ßCD polymer discs has been investigated. Drug release kinetics were carried out at physiological conditions of pH and temperature, and kinetic and diffusion constants were calculated. The drug release followed a simple Fickian diffusion mechanism for all the model drugs. Also, diffusion coefficients were calculated according to the simplified Higuchi model. Naproxen was also used to perform release assays from polymers containing different CDs. The βCD polymer showed the highest amount of drug loaded and the lowest one corresponds to the polymer containing αCD, in agreement with the affinities for naproxen of the corresponding cyclodextrins. It can be inferred that a simple Fickian diffusion mechanism occurs, except for the mixed polymers at pH 1.2 (anomalous transport) and in the case αCDP at pH 7.0 (burst phenomenon). Furthermore, the diffusion and relaxation contributions have been determined for the mixed polymers in order to achieve progress in the design of new polymer matrices according to the structure of the selected drugs. 2013-04-03T22:00:00Z http://hdl.handle.net/10171/28203 Title: Biodegradación de fenol en un reactor en régimen de spouted bed con partículas de ß-ciclodextrina Author(s) : Safont, B. (Bárbara) Abstract: A draft-tube spouted bed bioreactor with different types of aeration was developed to study the aerobic microbial degradation of aqueous phenol using a cyclodextrin-based support material. Since oxygen is a key in aerobic bioprocesses, the influence of different types of aeration on the volumetric mass transfer coefficient, kLa, was investigated. The values of kLa increased with gas spatial velocity, and decreased with increasing solid load, air flow distribution (spout to total flow ratio) and medium viscosity (carboxymethylcellulose solutions). The proposed correlations for kLa predicted the experimental data satisfactorily. Bacteria from activated sludge were acclimated to phenol in a continuous stirred tank bioreactor, and then immobilized onto the hydrogel particles within the spouted bed bioreactor. Microorganisms from cultures obtained in both bioreactors were isolated and characterized. Microbial population distribution in bioreactors was not only affected by phenol concentration, but also by oxygen and nitrogen availability, the system configuration and the presence of intermediates formed during phenol metabolization. A maximum elimination capacity of 6.63 kg-phenol/m3d was achieved in the spouted bed bioreactor, with Burkholderia cepacia being the dominant strain during high degradation periods. Batch experiments were carried out to evaluate the biodegradation of phenol by isolated dominant strains. Higher phenol concentrations inhibited the biomass and reduced the biodegradation rate. The modeling of batch phenol biodegradation indicated that the Haldane inhibitory model provided a good fit to the experimental data. Results showed that Acinetobacter baumannii and Burkholderia cepacia yielded the maximum specific growth rates. 2013-04-03T22:00:00Z http://hdl.handle.net/10171/28202 Title: Caracterización del proceso de muerte celular inducido por los derivados bisacilimidoselenocarbamato Author(s) : Lamberto, I. (Iranzu) Abstract: Bisacylimidoselenocarbamate derivatives (BSC) are potent anticancer agents with a strong cytotoxic activity against different types of tumour cells. Based in phosphatidylserine exposure on the cell membranes we show that BSC treatment resulted in enhanced cell death in leukaemia CCRF-CEM cells. DNA fragmentation detection in breast adenocarcinoma MCF-7 cells showed that BSC triggered cell death is concentration and time dependent. We also show that two of these compounds, BSC 3g and 3n, cause cell-cycle arrest in the late G2/M in MCF-7 cells. Consistent with this, a reduction in CDK1 and CDK2 expression with no change in cyclin A and B1 was observed in this cell line. Activation of caspase-2 was also detected. However, the involvement of the caspase-dependent pathway in the process of cell death induced by either BSC 3g or 3n is discarded since cell death could not be prevented by pretreatment with the pancaspase inhibitor z-VAD-fmk. Moreover, since reduced levels of p21CIP and Chk2 proteins but no change in p53 levels could be detected in MCF-7 cells after BSC 3g or 3n treatment our results suggest that BSC treated cells die from lethal mitosis. 2013-04-03T22:00:00Z http://hdl.handle.net/10171/28185 Title: Estrategias para la detección y caracterización funcional de nuevas translocaciones cromosómicas en cáncer Author(s) : Ortiz-de-Mendíbil, I. (Iñigo) Abstract: Cancer is a heterogeneous group of diseases whose initiation and progression is determined by the appearance of genetic and epigenetic alterations. Chromosomal instability in particular is one of the signatures of haematological malignancies. Therefore, genomic rearrangements like translocations, that cause the appearance of chimeric transcripts or deregulated expression of genes, are common mechanisms in tumor cells. Molecular characterization of fusion sequences has shown that, at least for a few genes, the breakpoints tend to cluster in specific regions. As result, the distribution of the breakpoints follows a non-random pattern, with few sites where the breakpoints are more frequent than would be expected by chance. Although several studies have shown the role of nucleotide motifs and local characteristics of the sequences as the cause of such non-random distribution, the relevance of the functional factors in defining the position of the breakpoints involved in chromosomal translocations has not yet been tested experimentally. In order to explain the non-random distribution of breakpoints in chromosome translocations we have studied functional factors such as protein domains as well as the need to maintain an intact reading frame in the fusion product. Until recently, fusion genes have been associated almost exclusively with hematological malignancies and mesenchymal tumors. Recent studies have shown, however, that fusions are also responsible for the pathogenesis of certain epithelial cancers, such as prostate cancer and NSCLC. For this reason we hypothesize that there must exist other rearrangements causing fusion genes in other solid tumors, but its description has not been possible until now because of methodological problems. Therefore, we have searched for novel fusion genes search using a new methodology based on exon microarrays. 2013-03-25T23:00:00Z http://hdl.handle.net/10171/28184 Title: Combinación de adyuvantes y bloqueo de mecanismos inmunosupresores como estrategias de vacunación terapéutica Author(s) : Aranda, F. (Fernando) Abstract: La activación de linfocitos T efectores capaces de reconocer a las células malignas que expresan antígenos tumorales podría dar lugar a nuevas estrategias de inmunoterapia para la eliminación tumoral. Sin embargo, la conversión de linfocitos T naive en efectores se encuentra dificultada por la pobre inmunogenicidad de los tumores, caracterizados por su baja expresión antigénica y la ausencia de señales inmunoestimuladoras que activen a las células presentadoras de antígeno (CPA). Por ello, la caracterización de una combinación de antígenos y adyuvantes que superen esta situación y activen respuestas antitumorales eficaces es un importante objetivo. Usando el melanoma B16-OVA como modelo de tumor poco inmunogénico, hemos ensayado diferentes combinaciones de antígeno y adyuvantes para el tratamiento de tumores establecidos. Sin la inclusión de antígenos tumorales exógenos, la administración del ligando de TLR7 Imiquimod y anticuerpos agonistas anti-CD40 activó solamente la inmunidad innata, que no rechazó los tumores. La administración de esta combinación de adyuvantes junto con OVA como antígeno tumoral indujo respuestas de linfocitos T que retrasaron el crecimiento tumoral pero no indujeron su rechazo. Sin embargo, el tratamiento con una combinación de los adyuvantes anti-CD40 y ligandos de TLR3 y TLR7 junto con el antígeno vehiculizado a las células dendríticas a través de TLR4, indujo el rechazo tumoral en el 50% de los animales. Esto se asoció a una mejor activación de la inmunidad innata y a la inducción de linfocitos T CD8+ polifuncionales de alta avidez, responsables del rechazo tumoral. Esta terapia activó no sólo respuestas frente a OVA, proporcionando protección futura frente al propio tumor, sino también respuestas frente a otros antígenos asociados al melanoma, que protegieron frente al tumor parental B16-F10. Estos resultados sugieren que una combinación múltiple de adyuvantes y la vehiculización del antígeno podría ser una estrategia útil en la inmunoterapia de tumores poco inmunogénicos. Junto a la baja inmunogenicidad intrínseca de las células tumorales, existen otros mecanismos inmunosupresores que llevan a la evasión el reconocimiento inmune o a la desactivación de los mecanismos efectores de células T anti-tumorales. Entre los mecanismos mejor caracterizados están las citoquinas inmunosupresoras, IL-10 y el TGF-beta, lo que ha sugerido que su inhibición podría tener un efecto beneficioso en las fases de activación y efectoras de la respuesta antitumoral. Mediante la combinación de las estrategias de vacunación mencionadas anteriormente con péptidos inhibidores y anticuerpos monoclonales bloqueantes de estas citoquinas hemos potenciado la respuesta inmunitaria frente a los antígenos tumorales. Esto ha supuesto que en el modelo de B16-OVA la combinación múltiple de adyuvantes junto con el bloqueo de IL-10 sea capaz de rechazar el 100% de los tumores. 2013-03-26T23:00:00Z http://hdl.handle.net/10171/28175 Title: Caracterización de los mecanismos de resistencia de aislamientos clínicos de Pseudomonas aeruginosa no sensibles a carbapenems y factores de riesgo asociados a su adquisición Author(s) : Íñigo, M. (Melania) Abstract: The epidemiology-related features of antibiotic resistant Pseudomonas aeruginosa strains (Pa) isolated in the University Hospital of Navarra from January 2002 to February 2009 were analyzed. An increase of Pa isolates not susceptible to carbapenems (Pa-nsc) was detected and the profile of antibiotic resistance of these organisms was markedly different from that of carbapenem susceptible Pa (Pasc). Both Pa-nsc and the overall Pa isolates increased their resistance to several antibiotic classes, whereas Pa-sc maintained their level of susceptibility. Phenotypic methods most commonly used for detection of metallo-beta-lactamase producing strains (MBL) including E-test MBL, simple microdilution test, double disk synergy test and disks combined test were compared and found to render 100% sensitivity. The combined disk test using imipenem and EDTA provided the greatest specificity. The susceptibility to doripenem in Pa isolates not susceptible to imipenem and meropenem was analyzed. Depending on the cut-off points established by CLSI, EUCAST and FDA, it was found that 28.6% to 11.9% of the strains not susceptible to imipenem were susceptible to doripenem, while 26.2% to 10.7% of strains not susceptible to meropenem were susceptible to doripenem. The mechanisms of resistance to carbapenems in clinical isolates of Pa-nsc were characterized. The altered expression of the porin OprD was the most common resistance mechanism (87.5%), followed by the overproduction of AmpC (33.3%). Four MBL-producing strains of the VIM-2 family were detected including the first MBL-producing strain sensitive to doripenem (MIC 1 ì/ml). The use of urinary catheter and the consumption of broad-spectrum antibiotics (piperacillin-tazobactam, carbapenems, fluoroquinolones and aminoglycosides) were established as risk factors for the acquisition of Pa-nsc. Exposure to hospital environment and the use of mechanical ventilation were identified as risk factors when the groups under comparison were Pa-nsc isolates versus isolates different from Pa. Finally, a prolonged hospital admission, the isolation of multiresistant Pa, the administration of chemotherapy and the use of immunosuppressive drugs were predictors of mortality attributable to Pa-nsc. 2013-03-24T23:00:00Z http://hdl.handle.net/10171/28134 Title: Estrés oxidativo y acortamiento de los telómeros en pacientes con Síndrome Metabólico: papel de la NADPH oxidasa Author(s) : Montero, L. (Laura) Abstract: The Metabolic Syndrome is a disease entity characterized by the joint presence of several metabolic and vascular disturbances (hypertension, central obesity, diabetes and dyslipidemia), whose prevalence increases with age, which is very closely related to the development of atherosclerosis. The shortening of telomere length in leukocytes, which is used as a marker of aging, has been associated with the cardiovascular risk factors included in the definition of Metabolic Syndrome, with insulin resistance promoting their shortening. The simultaneous presence of these factors leads to increased oxidative stress mediated by the phagocytic NADPH oxidase, as reflected in the increased levels of oxidative stress marker TBARS, which accelerates the erosion of telomeres primarily through telomeric DNA oxidation. Thus, NADPH oxidase overactivity promotes telomere shortening in Metabolic Syndrome and insulin resistant patients, and increases the risk of vascular complications, as shown by the greater prevalence of several surrogate markers atherothrombotic risk (carotid intima-media thickness and metalloproteinase-9) in these patients. The involvement of the NADPH oxidase in this process is supported by in vitro findings in cultured murine macrophages Finally, our in vivo and in vitro results underline a relevant role for hyperglycemia in the telomere shortening by promoting NADPH oxidase-dependent oxidative stress. 2013-03-14T23:00:00Z http://hdl.handle.net/10171/28133 Title: Mechanisms involved in lung cancer bone metastasis:DDR1 and microRNAs as paradigms Author(s) : Valencia, K. (Karmele) Abstract: Bone metastasis represents one of the most devastating consequences of lung cancer associated with poor prognosis. Given the relevance of cell-matrix interactions and the regulatory mechanisms of large multigenic networks implicated in metastasis, we studied the tyrosine kinase DDR1 and miRNAs as two paradigms involved in this process. DDR1 is a collagen receptor found in highly invasive tumor cells. Interestingly, high levels of DDR1 were associated with a decrease survival in stage I lung cancer patients patients. Using a model of lung cancer bone metastasis we demonstrated that abrogation of DDR1 levels led to stunted decrease in metastatic activity mediated by impaired homing and colonization. These effects were associated with a decreased tumor cell survival and decreased invasive and osteoclastic activities. Thus, DDR1 represents a therapeutic target involved in bone metastasis. Using the same model, we unveiled the relevance of a novel mechanism of metastatic colonization consisting in the tumor release and transfer of miR-192 within CD63+ enriched exosomes to the endothelial compartment of the osseous milieu. Exosome fusion to endothelial cells was accompanied by the repression of key proangiogenic chemokines. These findings were associated with a functional impairment of the tumor-induced angiogenic program. miR-192 governs non-cell autonomous functions that globally impair metastatic bone colonization. Interestingly, serum levels of miRNAs were asssociated with osseous colonization. Thus, these two paradigms reveal novel mechanistic insights and identify a new window of opportunity for innovative strategies of thereputic intervention. 2013-03-14T23:00:00Z http://hdl.handle.net/10171/27662 Title: Effect of External Fields on the Dynamics of Colloidal Phase Transitions Author(s) : Pichumani, M. (Moorthi) Abstract: In this experimental work, the effects of the external fields on the colloidal phase transition from liquid phase to solid deposits (evaporative colloidal phase transition) have been investigated. The external fields are applied while the transition is in process. The experiments are performed with two different transition duration: (a) In the experiments of long duration, the fluid is allowed to evaporate by exposing the colloidal dispersion (negatively charged polystyrene particles of diameter 1.3 μm dispersed in ultra pure water) to an environment at high temperature (63 degree C) and low humidity (below 2% RH). The colloidal dispersion is placed between the two vertical conducting substrates. Electric fields (DC) are of the order of 1 V/mm and they are applied perpendicularly to the substrates while the phase transition is in process. When the continuous phase evaporates, the contact line recedes. We measure the speed of the receding contact line for different initial concentrations (0.1%, 0.3% and 0.5% w/w, respectively) as well as for varying electric field. The dried deposits of colloidal particles are then correlated with the initial conditions and electric field strength of the respective experiment. To deepen the understanding of the three phase contact line in vertical deposition of colloids, the meniscus of a colloid is observed while the weak external field (AC) of the order of 1 V/mm and 1 Hz is applied. In this case, the working temperature is relatively low (room temperature) when compared to the previous set of experiments explained above and consequently the contact line does not recede during the measurement time. The applied field generates flows near the meniscus through electrokinetic and electrowetting mechanisms resulting in the formation of clusters of colloidal particles in the fluid matrix along the horizontal contact line. The clusters are separated by a well defined characteristic length and in our experimental conditions, they remain between 5 and 15 minutes. (b) In the experiments of short duration (spin-coating), the fluid phase of the colloidal dispersion is made to evaporate in fractions of a second by pouring a volume of the dispersion over the spinning substrate (spinning rate is of the order of 1000 rpm). In the absence of the magnetic field, equivalent film thickness for different kinds of colloids (superparamagnetic and nonmagnetic, respectively) are compared. After that, external fields are applied while the dispersion is pipetted onto the spinning substrate. On the one hand, external magnetic fields up to 0.066 T are applied while spin-coating the dilute superparamagnetic colloidal dispersion (polystyrene coated magnetite of diameter 1 to 2 μm and SiO2 coated magnetite of diameter 1.51 μm dispersed in ultra pure water, respectively). A spin-coating model is constructed by considering the evaporation of the fluid and the particulate characteristics of the spin-coated deposits. Morphological transition from sparse to submonolayer deposits (clusters) of superparamagnetic particles occurs. The magnetic field increases the effective viscosity of the dispersion through magnetic dipole interactions. On the other hand, to overcome the axial symmetry imposed by the spin-coating (in experiments with nonmagnetic particles of high initial concentration, 40% w/w), nonuniform alternating electric fields of the order of 0.1 kV/mm; frequency of the order of 1 kHz are applied while spin-coating the colloidal dispersion (SiO2 particles of diameter 458 nm dispersed in 2-Pentanone) over the patterned conducting substrate. We conclude that the dielectrophoretic confinement of the dispersion affects the hydrodynamic flows resulting in a predefined direction for the colloidal deposits. Thus, the electric field breaks the axial symmetry. 2013-01-17T23:00:00Z http://hdl.handle.net/10171/23847 Title: Himenópteros parásitos de la serie Parasitica (Chalcidoidea, Mymaridae), relacionados con insectos plaga en el maíz de Navarra Author(s) : Baquero, E. (Enrique) Abstract: Esta investigación constituye un estudio de los mimaridos (hymenoptera, mymaridae) relacionados con el maíz en Navarra. Se han recogido 72 muestras en 60 puntos utilizando dos métodos de muestreo: trampa malaise y captura directa con manga entomológica. La extracción ha sido directa bajo lupa binocular y se han separado 7268 mimaridos de un total de 94038 artrópodos. Representan el 7,72% del total. Estos mimaridos han sido clasificados y separados en 37 especies y 11 géneros diferentes. Los géneros anagrus haliday, 1833 y gonatocerus nees, 1834 han aparecido como los mas relacionados con el cultivo del maíz en Navarra y dos de sus especies las distribuidas mas ampliamente por todo el territorio: anagrus atomus linnaeus, 1767 y gonatocerus litoralis haliday, 1833. se ha comprobado la presencia de la especie zyginidia scutellaris herrich-schaffer, 1838 (homoptera, cicadellidae) en todos los campos de maíz de navarra. Esta especie de cicadelido parece el huésped mas habitual de anagrus atomus. Se ha comprobado la elevada presencia de insectos y de otros artrópodos en los campos de maíz debido a la ausencia de tratamientos químicos contra los insectos perjudiciales. 2012-11-27T23:00:00Z http://hdl.handle.net/10171/23618 Title: Análisis del proceso de descarga de un silo con un obstáculo cerca del orificio Author(s) : Lozano, C. (Celia) Abstract: Jamming is an important problem in numerous industrial processes, and in other situation such as traffic and evacuation. Some reports show that an obstacle placed before the exit may prevent jamming a pedestrian flow. However, this is a general hypothesis and there are still related questions that have not been fully addressed, mainly the dynamics of the system or the optimal position of the obstacle. The present work aims at shedding some more light on these phenomena. We present an experimental work where we analyze systematically and under well controlled conditions, the macroscopic and microscopic processes involved during the discharge of a silo by gravity with an obstacle placed before an orifice. We fixed at the size of the orifice and change the position of the insert. In order to do that, we have designed a 2D silo with transparent walls which allowed visualization of the particles. The first conclusion of this work is the existence of an optimal position of the obstacle where the jamming probability is drastically reduced. If the obstacle is far away from the orifice, it does not have any effect. When the obstacle is close to the orifice, the avalanche size is higher and the probability that a particle clogs the outlet decreases. We find that, if the insert position is properly selected, the probability that the granular flow gets jammed can be decreased by a factor of 100. This dramatic effect occurs without any remarkable modification of the flow rate or the packing fraction above the outlet. However, for low positions of the insert we saw that some particles in the region of arch formation can be displaced upwards. This phenomenon is less evident when the insert is at high positions. This effect could be related with the reduction of the clogging probability. So, we propose that the mechanism by which the insert prevents clogging is a reduction of the pressure exerted to the particles in the region of arch formation. 2011-12-31T23:00:00Z http://hdl.handle.net/10171/23501 Title: Compensación ecológica en la evaluación de impacto ambiental en España: situación y propuestas de acción Author(s) : Villarroya-Ballarín, A. (Ana) Abstract: This article presents an environmental impact assessment (EIA) controversial case, which was finally settled by the passing of a sentence. The sentence enforced a payment to compensate for the economic damage caused to a fish farm through local environmental changes in Urola river estuary, located in the Basque Country. The damage was allegedly caused by a breakwater extension built at the mouth of an estuary nearby the farm, and linked to a recreation port project located within the estuary. While the sentence settled the meaning of compensation from an economic perspective, it raised by contrast some questions on the difficulty of undertaking ecological compensation within EIA practice, using of this particular case. Maybe these difficulties account for the lack of compensation in coastal development projects, which we have observed in a variety of cases in Spain, particularly for coastal development projects.-------------------------Este artículo describe un caso polémico de Evaluación de Impacto Ambiental (EIA), finalmente resuelto tras la aprobación de una sentencia legal. La sentencia imponía a la compañía promotora un pago como compensación al daño económico que los cambios ambientales originados por el proyecto causaron a una piscifactoría localizada en el estuario del río Urola, en el País Vasco. El daño fue supuestamente ocasionado por la ampliación de un dique construido en dicho estuario, proyectado para mejorar el acceso a un puerto recreativo próximo. A raíz de este caso se plantean y discuten ciertas cuestiones en torno a la dificultad de implantar medidas de compensación ecológica a través de la EIA, utilizando lo ocurrido en torno a la compensación económica como contrapunto. Tales dificultades pueden ser la causa de la escasa compensación que se aplica en proyectos costeros, registrada en este artículo para varios casos en España. 2011-12-31T23:00:00Z http://hdl.handle.net/10171/23499 Title: Diseño racional de péptidos derivados de la lactoferricina humana con actividad permeabilizante mejorada y capacidad de producir Permeabilidad Asociada al Efecto Postantibiótico Author(s) : Razquin-Olazarán, I. (Iosu) Abstract: Para la realización de este estudio, se establecieron los siguientes objetivos: 1. Desarrollar un modelo cuantitativo que relacione la estructura química con la actividad permeabilizante de los péptidos disponibles actualmente y diseñar una nueva generación de péptidos con capacidad permeabilizante mejorada. 2. Determinar la actividad permeabilizante y antimicrobiana de los nuevos péptidos frente a P. aeruginosa y caracterizar su espectro de acción frente a otras especies bacterianas. 3. Caracterizar la capacidad neutralizante de endotoxina de los nuevos péptidos y estudiar posibles asociaciones entre parámetros con interés terapéutico. 4. Determinar la toxicidad y actividad hemolítica de los nuevos péptidos. 5. Estudiar las relaciones estructura-actividad y establecer las bases estructurales que determinan la actividad permeabilizante de péptidos catiónicos sobre P. aeruginosa. 6. Seleccionar los mejores péptidos permeabilizantes y evaluar su capacidad para potenciar antibióticos in vitro y en un modelo animal de sepsis por P. aeruginosa. 7. Determinar si los péptidos pueden producir efecto postantibiótico y si la presencia simultánea de antibióticos en las terapias combinadas puede potenciar el efecto post-antibiótico de los péptidos. 2011-12-31T23:00:00Z