Tesi realitzada al Centre de Recerca en Agrigenòmica (CRAG) / Plants germinated in the dark under the soil surface, undergo skotomorphogenic development. Once they emerge from the soil surface perceive light for the first time. Then, seedlings switch from skotomorphogenic to photomorphogenic development, a process that is known as seedling deetiolation. At this moment, seedlings rapidly form the photosynthetic apparatus to start to produce energy and avoid photodamage. In addition, seedlings adapt their morphology to enhance light capture for photosynthesis, inhibiting hypocotyl elongation and stimulating cotyledon separation and expansion. At the molecular level, after first exposure to light, phytochromes photoreceptors interact with a subgroup of transcription factors named PIFs (Phytochrome Interacting Factors). This light-induced interaction between the phytochromes and PIF initiates a cascade of transcriptional changes that allows plants to adjust to the new light environment. At the beginning of this thesis, the PIF-regulated transcriptional networks that operate during photomorphogenesis had been described. However, the primary target genes that implement downstream cellular functions or amplify the PIF signaling pathway had not yet been identified. Therefore the main goal of this work was to identify the downstream effector genes of the PIF transcription factors to elucidate the PIF-regulated transcriptional network that represses photomorphogenic development. In order to identify new regulators of seedling deetiolation acting downstream of PIF transcription factors, we designed a genetic screen to search for mutants that suppress the constitutive photomorphogenic phenotype of the pifq mutant. Interestingly, our genetic screen has allowed the identification of 23 genes that suppress or enhance the pifq constitutive photomorphogenic phenotype. Among them, we found a big representation of genes codifying for chloroplast proteins, then, we decided to study the interplay of chloroplast biogenesis (a PIF-regulated process) and chloroplast retrograde signaling in the regulation of seedling deetiolation. The work performed allowed us to determine that dysfunctions in chloroplast biogenesis repress photomorphogenesis, through the transcriptional repression of light induced-PIF repressed genes, in order to adjust seedling development to the photosynthetic capacity of the chloroplast. Moreover, we studied the role of CDF5, a transcription factor found in our suppressor screening, and we concluded that the transcriptional regulation of CDF5 by the circadian clock and the PIF transcription factors defines a novel mechanism of regulation of growth under diurnal conditions. / Las plantas, durante todo su ciclo vital, adaptan constantemente su desarrollo y crecimiento a los cambios que se producen en el ambiente que las rodea. En periodos de oscuridad, ya sea cuando las plantas germinan bajo la superficie de la tierra o cuando crecen en condiciones diurnas (noche y día), se acumulan en el núcleo los factores de transcripción llamados Phytochrome Interacting Factors (PIFs). Estos factores de transcripción regulan la expresión de miles de genes con el fin de inducir crecimiento y reprimir el desarrollo fotomorfogénico. Tras la germinación en oscuridad, una vez las plantas alcanzan la superficie y se exponen a la luz, los fitocromos, fotoreceptores que perciben la presencia de luz roja y roja lejana, se activan y se traslocan al núcleo, donde inducen la degradación de los factores de transcripción PIFs. La degradación de estas proteínas produce amplios cambios en el transcriptoma de las plantas induciendo el desarrollo fotomorfogénico. Al inicio de la tesis, las redes transcripcionales reguladas por los PIFs habían sido descritas, sin embargo, los genes que inician la cascada transcripcional que implementan las funciones celulares que permiten a las plantas desarrollarse fotomorfogénicamente eran desconocidos. Nuestro principal objetivo ha sido determinar estos genes, para ello realizamos un cribado de supresores del fenotipo fotomorfogénico constitutivo de plantas mutantes de genes PIF. Los resultados del cribado nos han permitido identificar nuevos reguladores del desarrollo fotomorfogénico que actúan como intermediarios de la cascada de señalización iniciada por los factores de transcripción PIF. Estos resultados permiten ampliar el conocimiento de la función transcripcional de los PIFs, mostrando ejemplos específicos de genes tanto inducidos como reprimidos. Además, nuestro trabajo ha permitido determinar que la biogénesis del cloroplasto es un proceso necesario para que las plantas se desarrollen fotomorfogénicamente.

Las gramíneas perennes han sido catalogadas como cultivos energéticos con alto potencial debido a sus beneficios ambientales y su capacidad de crecimiento en regiones con condiciones adversas. El objetivo principal de esta Tesis ha sido caracterizar las respuestas ecofisiológicas de dos especies de gramíneas perennes (Arundo donax L. (C3) y Panicum virgatum L. (C4)) a diversas condiciones de estrés, como son el estrés hídrico, el estrés salino y el estrés por baja temperatura y oscuridad continua. En el experimento I, distintos ecotipos de Arundo donax L. fueron sometidos a condiciones de estrés hídrico y salino en la Universidad de Barcelona (España; Exp. Ia y Ib) y en la Universidad de Catania (Italia; Exp. Ib). A su vez, se clasificaron de acuerdo a su tolerancia a estos estreses en función de un Índice de Susceptibilidad al Estrés (SSI). En el experimento II, fueron las dos especies (Arundo donax L. y Panicum virgatum L.) las que se sometieron a las mismas condiciones de estrés hídrico y salino (Exp. IIa) y a estrés por baja temperatura y oscuridad continua (Exp. IIb). Por último, en el tercer experimento se estudió el efecto del estrés hídrico en ambas especies (Arundo donax L. y Panicum virgatum L.) mediante el uso de isótopos estables de 13C y 15N. En los tres experimentos se midieron los efectos del estrés en parámetros fisiológicos (tasa fotosintética, conductancia estomática, contenido relativo del agua en la hoja, contenido de clorofila) y en parámetros de biomasa (área foliar, área de los tallos, peso seco total, índice S/R, área específica foliar, etc). A su vez, en el experimento III se determinó la composición isotópica del 13C de la materia orgánica total (delta13CTOM), de la respiración en oscuridad (delta13CR) y de los azúcares solubles totales (delta13CTSS) así como de la composición isotópica del 15N de la materia orgánica total (delta15NTOM). En condiciones control, los resultados indicaron una tasa fotosintética en Arundo donax L. (C3) similar a la de Panicum virgatum L. (C4), aunque la producción de biomasa fue mayor en esta última especie, debido principalmente al mecanismo de concentración de CO2 característico de este tipo de ruta metabólica. A su vez, se observó como Arundo donax L. estaba más empobrecida en 13C que Panicum virgatum L. . En condiciones de estrés, tanto hídrico como salino, se observó como el descenso de la tasa fotosintética (Asat) fue íntimamente ligado a la disminución de la conductancia estomática (gs), disminuyendo a su vez la producción de biomasa en ambas especies. Según los resultados, Arundo donax L. estaría mas afectado por el estrés hídrico que por la salinidad. A su vez, los resultados indicarían cierta tolerancia de Panicum virgatum L. al estrés hídrico y al estrés salino en comparación con Arundo donax L. . La baja temperatura, además de funcionar como un crioprotector de enzimas, actuaría retardando ligeramente el efecto negativo de la oscuridad. A su vez, se observó un metabolismo más lento en Panicum virgatum L. frente a bajas temperaturas y oscuridad continua, indicando una mayor tolerancia a este estrés. Mediante el uso de isótopos estables se ha observado como el tallo y el rizoma de ambas especies funcionarían como órganos sumideros de carbono y las hojas órganos sumideros de nitrógeno. / Perennial rhizomatous grasses are regarded as leading energy crops due to their environmental benefits and their suitability to regions with adverse conditions. The main objective of this Thesis was to characterize the ecophysiological responses of two species of perennial grasses (Arundo donax L. (C3) and Panicum virgatum L. (C4)) to several stress conditions such as water stress, salt stress and low temperature and continuous darkness stress. Different physiological parameters (photosynthetic rate, stomatal conductance, relative water content and chlorophyll content) as well as biomass parameters (leaf area, stem area, total dry weight, S/R index, specific leaf area ratio) were measured in both species. Moreover, the isotopic composition of 13C and 15N of the total organic matter (delta13CTOM and delta15NTOM), of the darkness respiration (delta13CR) and of the total soluble sugars (delta13CTSS) were determined. In control conditions, results showed a similar photosynthetic rate in both species, although biomass production was higher in Panicum virgatum L. (C4), mainly due to the CO2 concentration mechanism characteristic of this type of metabolic pathway. A decrease in photosynthetic rate (Asat) closely linked to the decrease in stomatal conductance (gs) was observed under stress conditions, along with a decrease in biomass production. According to the results, Arundo donax L. would be more affected by water stress than by salinity. In turn, the results indicate some tolerance of Panicum virgatum L. to water stress, salt stress and low temperature and continuous darkness compared with Arundo donax L. . The use of stable isotopes have shown that the stem and rhizome of both species are carbon sink organs, and the leaves are nitrogen sink organs.

En aquest treball han estat estudiades nombroses restes de lagomorfs (O. Lagomorpha, Cl. Mammalia) de diversos jaciments del Pliocè i Pleistocè europeus, com Zújar - 11 (Granada), Casablanca 1 (Castelló), Perrier (França), Valdarno (Itàlia), Barranco León 5 i Fuente Nueva 3 (Granada), Cueva Victoria (Murcia), Sima del Elefante 9 (Atapuerca), Dmanisi (Geòrgia), Cova del Toll i El Carmel (Barcelona). S'ha prestat especial interès en la família Leporidae, que és la que presenta més problemàtiques en la sistemàtica. Abans de dur a terme l'estudi sistemàtic dels fòssils, ha estat necessari reconèixer els principals caràcters morfològics que diferencien els taxons de lepòrids actuals que viuen en la regió mediterrània occidental. Aquest estudi s'ha centrat bàsicament en l'esquelet i, especialment, en el tercer premolar inferior. Així, d'una banda, les relacions entre els paràmetres biomètrics han permès diferenciar els gèneres Oryctolagus i Lepus; d'altra banda, a partir de l'anàlisi morfomètrica del P3 que s'ha efectuat mitjançant landmarks i transformades de Fourier, també ha sigut possible discriminar entre ambdós gèneres. D'aquesta manera, a partir d'aquests dos estudis dels lepòrids actuals s'ha realitzat una assignació taxonòmica de les restes fòssils.Pel que fa als ocotònids (Fam. Ochotonidae), s'ha identificat Prolagus michauxi a Zújar (sent la resta més moderna d'aquesta espècie), Prolagus calpensis a Casablanca i Cueva Victoria, Prolagus sp. a Barranco León 5, i Ochotona sp. a Dmanisi.Respecte els lepòrids, s'ha identificat la presència d'un Leporidae indet. a Perpignan (França), tot i que probablement es tracti de Trischizolagus o Hypolagus; d'Oryctolagus sp. a Zújar 11, Casablanca, Barranco León 5, Fuente Nueva 3 i Sima del Elefante TE9; d'Oryctolagus lacosti a Perrier (França) i Valdarno (Itàlia); d'Oryctolagus giberti (nova espècie per la ciència) a Cueva Victoria i El Carmel; d'O. cuniculus a la Cova del Toll, i de Lepus sp. en el jaciment de Sima del Elefante TE9.Cap resta fòssil clarament atribuïble a O. cuniculus ha estat identificada en el Pleistocè inferior, fet que no concorda amb els resultats dels estudis moleculars. D'altra banda, la presència de veritables llebres ja en el Pleistocè inferior a Europa occidental, fins ara en discussió, queda confirmada a partir del material de Sima del Elefante TE9. / Fossil lagomorphs (Lagomorpha, Mammalia) are common in Pliocene and Pleistocene European sites but they have been understudied until now. Fossil remains are craneal and postcraneal bones, teeth being particularly abundant, but the high morphological variability of this group makes taxonomic identification difficult. To solve this main obstacle, a morphologic study of Recent and fossil lagomorphs, paying special attention to the morphometry of the third lower premolar of modern Leporids from the Western Mediterranean area has been carried out. Landmark and elliptic Fourier analyses are applied for the first time to the study of this group. So, the results allow to clearly discriminate the leporid genera Oryctolagus and Lepus, and are very useful for the determination of fossil remains.Studied material was either directly sampled in the outcrops or belongs to historical collections housed in Museums. The main considered localities are Perrier (France), Valdarno (Italy), Dmanisi (Georgia), Zújar 11, Casablanca, Barranco León and Fuente Nueva, Cueva Victoria, Sima del Elefante, Cova del Toll and El Carmel (Spain).The following taxa have been identified: Prolagus sp., Prolagus michauxi, Prolagus calpensis, and Ochotona sp. (Ochotonidae); and Oryctolagus sp., Oryctolagus lacosti, Oryctolagus giberti (new species), Oryctolagus cuniculus, and Lepus sp. (Leporidae). Oryctolagus giberti shows several intermediate characters between O. laynensis, the first known representative of the genus, and the modern European rabbit (O. cuniculus), turning it in a firm candidate to occupy a phylogenetic place between these two species. The remains of P. michauxi of Zújar (upper Pliocene) represent the most modern record of this species known until now, and the abundant fossils of Lepus sp. from Sima del Elefante confirms the early presence of this genus in the Lower Pleistocene of Europe.

Distinguishing population units of small cetaceans continuously distributed in a widespread area is challenging, but critical for their conservation and management. The common dolphin (genus Delphinus) has a wide distribution range that has led to the differentiation of a number of morphotypes which, until today, remain of unclear taxonomic adscription. In many areas, two morphotypes were initially distinguished and later separated into two species: the long-beaked common dolphin, or Delphinus capensis, and the short-beaked common dolphin, or Delphinus delphis. The general aim of the present thesis is to investigate the taxonomy, morphology, distribution, and habitat use of the common dolphins (genus Delphinus) occurring in the eastern sub-tropical Atlantic Ocean (NW Africa). This area is amongst those most productive in the world. It is characterized by a quasi-permanent upwelling zone that promotes high biological productivity and a highly diverse and abundant fauna of marine mammals. It has been proposed that the short- and long-beaked forms of common dolphins occur sympatrically in this area, a scenario that provides a unique opportunity to discriminate between the two morphotypes and investigate whether differences are of taxonomic relevance. For the present thesis we investigated the local marine trophic network and the relationship between apex predators, as well as the distribution (offshore vs. inshore) and niche segregation (trophic level exploited) of the two common dolphin morphotypes. Additionally, differences in morphology and habitat use between NW Africa common dolphins and those from other areas, particularly from the northeastern and southeastern Atlantic Ocean, were investigated. Because research of intra and inter specific population variability requires a multiplicity of approaches, different methods were used, including stable isotope analyses of carbon (δ13C) and nitrogen (δ15N) in bone, and measurement-based and 'landmark'-based (geometric) morphometric analyses of the skull. The results obtained revealed that most of the marine mammal species distribute in the outer continental shelf and the upper slope, and that common dolphins are rarely distributed inshore, displaying a typical oceanic behaviour. With the exception of baleen whales, common dolphins showed the lowest trophic level of all marine mammals analyzed, despite the fact that there was large variability between individuals in the exploitation of food resources, possibly to adapt to local environmental variations. The presence of both short- and long-beaked morphotypes of common dolphins was confirmed off the coast of NW Africa, with the short-beaked form inhabiting waters closer to coast and feeding at a lower trophic level than the long-beaked form. Morphological analysis of the skull revealed that variation in relative beak length in common dolphins from NW Africa was larger than in other Delphinus populations worldwide; as opposed to other regions, relative rostrum size followed a clinal variation and intermediate ratios were found. There were significant differences between common dolphin populations and species analyzed in the size and shape components of the skull. The skull of the short-beaked morphotype from NW Africa was shorter but broader than that of the long-beaked. However, despite the differences, there is a closer morphological similarity between the short-beaked morphotype of NW Africa and Delphinus delphis, and between the long-beaked morphotype of the same region and Delphinus capensis. We conclude that taxonomic splitting of common dolphins in this area into two putative species should be postponed until further research is conducted because skull differentiation could be related to niche segregation and not to speciation. Furthermore, the above results indicate that the taxonomic model described for the Northeast Pacific should not be generally applied to other areas where the sort- and long-beaked morphotypes co-habit. / Distinguir unidades poblacionales de pequeños cetáceos distribuidos de forma continua en un área extensa es fundamental para su conservación y gestión. En el amplio rango de distribución de los delfines comunes se han establecido varios morfotipos de adscripción taxonómica incierta, identificados por la longitud relativa de su morro. En muchas áreas, dos morfotipos fueron distinguidos y más tarde separados en dos especies: el delfín común de morro largo, Delphinus capensis, y el delfín común de morro corto, Delphinus delphis. El objetivo general de la presente tesis es investigar la taxonomía, morfología, distribución, y uso del hábitat del delfín común (género Delphinus) en el este del Océano Atlántico Subtropical (NW África). Se ha propuesto que las formas de delfín común de morro corto y largo ocurren en simpatría en esta área, lo que permite una oportunidad única para discriminar entre los dos morfotipos e investigar si las diferencias son de importancia taxonómica. Los resultados han demostrado una gran variabilidad entre los individuos en la explotación de los recursos alimentarios, posiblemente para adaptarse a las variaciones ambientales locales del ecosistema. La presencia de ambos morfotipos de delfines comunes se confirmó en la costa NW de África; la forma de morro corto habita aguas más cercanas a la costa y se alimenta en un nivel trófico inferior a la de morro largo. El análisis morfológico del cráneo reveló que la variación en la longitud del morro es más grande que en otras poblaciones, con el morfotipo de morro corto presentando un cráneo más corto pero más amplio que él de morro largo. Como era previsible, existe una similitud morfológica más cercana entre el morfotipo de morro corto del NW de África y Delphinus delphis, y entre el de morro largo y Delphinus capensis. La división taxonómica de delfines comunes en dos especies, en esta área, debe posponerse hasta que se realicen más investigaciones, ya que la diferenciación craneal puede estar relacionada con la segregación de nicho y no con la especiación. Además, el modelo taxonómico descrito para el Pacífico Nordeste no debe aplicarse indiscriminadamente a otras áreas donde ambos morfotipos cohabitan.

La (+)-pulegona, I, reducida con sodio y éter-agua da, además de mentoles, productos de condensación, siendo uno de ellos un reductodímero de fórmula C(20)H(36)O(2) con los dos oxígenos en forma de hidroxilo. La oxidación demuestra que uno de ellos es de carbinol secundario, rasando el producto de partida a un cetol de fórmula C20H3402 (1a). Si la reducción de la (+)-pulegona se hace con amalgama de aluminio se forma directamente un cetol de la misma fórmula, pero distinto del anterior, transformable en otros y uno de ellos el citado. La reducción con amalgama de aluminio se ha trabajado en el Laboratorio de un modo multindicativo y exhaustivo (1f), permitiéndonos transformar un 30% de la pulegona en cetoles cristalinos. Hasta el presente se han obtenido así cuatro cetoles en cantidades suficientes para trabajarlos, y también en muy pequeña cantidad un 5º cetol. En las varias publicaciones y tesis doctorales proce-dentes del Laboratorio sobre el tema (1a-1f) se ha fijado como estructura de todos estos cetoles la representada en las fórmulas III y IV, explicándose su formación por la se¬cuencia 1. En cuanto a la configuración, la tienen fija y R los átomos de carbono 4 y 5', por ser la de los mismos átomos en la pulegona de origen, mientras se configuran durante el proceso los átomos de carbono 1, 6 y 7, explicando que pueden ser varios, hasta 8, los cetones en cuestión.

The concept of nanotechnology is attributed to Nobel prize winner Richard Feynman who gave a very famous, visionary in 1959 (published in 1960) during one of his lectures, saying: "the principles of physic, as far as I can see, do not speak against the possibility of maneuvering things atom by atom". At the time, Feynman’s words were received as pure science fiction". Today, we have instruments that allow precisely what Feynman had predicted: creating structures by moving atoms individually. In principle, the ultimate results of this research study leads to the synthesis of magnetic and porous carbon based nanoparticles as the material and tool for biomedical applications. Currently, we are in a battle with a dangerous and destructive diseases such as cancers, and nanotechnology is then presented as a tool that can help us win control. This work is to support medical and other applications of nanotechnology specifically aimed to prepare carbon based nanoparticles. Magnetic nanoparticles are being of great interest because of their unique properties especially in drug delivery, hyperthermia, magnetic resonance imaging and cell separation. In many clinical situations, medication doses are oversized as a result of impaired drug absorption or tissue unspecific delivery. The ultimate goal of magnetically controlled drug delivery and drug therapy is to selectively delivering drug molecules to the diseased site without a concurrent increase in its level in healthy tissues. Consequently, in this research study the objective is to develop an approach to control the synthesis of carbon encapsulated iron nanoparticles in the form of core@shell nanostructure. Accordingly, understanding and revealing the growth mechanism of carbon encapsulated iron nanoparticles is necessary by doing characterization. Furthermore, engineering of suitable carbon based nanoparticles for biomedical applications has been also considered. Common challenges for synthesis of carbon encapsulated iron nanoparticles are improving uniformity, enhancing coating protection and controlling particles compositions, shape and core/shell sizes. In addition, due to the lack of comprehensive understanding of the optimal parameters and formation mechanism most of the current fabrication process are empirical, which means a large number of experimental trials are required to optimize any given process. Since the last two decades, arc discharge technique leads to the discovery of two important carbon based materials, nanotubes and fullerenes. However, the formation of nanomaterials by thermal plasma still remains poorly understood and need further investigation. The focus in this study is on synthesis of carbon based nanoparticles by arc discharge method, particularly carbon encapsulated iron nanoparticles in the form of Core@Shell nanostructure. An arc discharge reactor that was patented by FEMAN group was used with slight modification. The growth processes were elucidated through many experiments and characterizations. Precise control over carbon encapsulated iron nanoparticles were addressed. In addition, a new carbon encapsulated multi iron nanoparticles is introduced. The results have been lead to new elements for understanding the growth mechanism of iron core and carbon shell nanostructure. In order to improve the synthesis process, a new modified arc discharge reactor was developed and implemented. Two new materials are prepared through a new facile synthetic method; carbon nanoparticles decorated by fullerenes and spherical porous carbon microparticles. Last but not least, in this research medical application requirements have been taken into account to prepare suitable nanoparticle. / El concepto de la nanotecnología se atribuye al ganador del premio Nobel Richard Feynman, científico visionario, quien dio una muy famosa conferencia en 1959 (publicada en 1960), en la que dijo: "los principios de la física, por lo que yo puedo ver, no están en contra de la posibilidad de maniobrar los objetos átomo por átomo "(Feynman, 1960). En ese momento, se recibieron las palabras de Feynman como pura ciencia ficción, sin embargo, a día de hoy, tenemos instrumentos que permiten precisamente lo que Feynman ya había predicho: La creación de estructuras de átomos en movimiento de forma individual. En principio, los resultados finales del presente trabajo de investigación conduce a la síntesis de nanoestructuras del tipo core@shell, consistentes en nanopartículas de hierro encapsulado en carbono, en nanopartículas de carbono decoradas con fullerenos y micropartículas de carbono porosas esféricas como material y herramienta para aplicaciones biomédicas. Actualmente, nos encontramos en un frente contra enfermedades peligrosas y destructivas como el cáncer, y la nanotecnología se presenta como una herramienta que nos puede ayudar a establecer un control de este tipo de dolencias. Este trabajo se enmarca en la Nanotecnología y tiene por objetivo el estudio y preparación de nanopartículas a base de carbono que puedan ser útiles para ciertas aplicaciones aplicaciones médicas o biomédicas y otras del ámbito de la nanotecnología más general.

The objective of this work was to study two different light management approaches to enhance the efficiency of thin film Si solar cells and these were the manipulation of the light path (light trapping) and changing the incoming photon energy (upconversion). In the first approach the light path was manipulated by creating either periodic or random textured interfaces. Periodic patterns were created at the front AZO by means of direct laser ablation. Amongst all the patterns assessed, the best result was achieved with a linear pattern of 10 lam of pitch and 360 nm of groove depth, that yielded to an Rs of 11 SI/sq and a haze of 12.7% at 600 nm. However structures in the sub-micrometer range cannot be created because the minimum period is limited by the laser spot. By means of the Aluminum Induced Texturing method (AIT) random textures were performed on glass substrates. In this method, a thin Al film is deposited onto a glass substrate and a redox reaction between the Al and the SiO2 of the glass is induced by high temperature annealing. The reaction products are wet-etched and the result is a uniform and rough glass surface. The process parameters were varied in order to control the resultant glass roughness and it was found that the most critical was the Al deposition method. By using evaporation smooth U-shaped craters morphology and roughness up to 90 nm were created, whereas the sputtered films resulted in rough and porous textures with roughness until 145 nm. AZO grown over the U-shape crater morphology led to a double texture with haze values above 10% at 600 nm, transparency above 84%, and Rs-7 SI/sq whereas AZO over very rough glass resulted in a cauliflower-like surface with haze values >32% at 600 nm, Rs around 9.5 SI/sq and transmittance of 74%. A-Si:H solar cells were deposited on different AIT textures and an improvement of the short circuit current, as well as a reduction of the device reflectivity was achieved in all cases in comparison to the cells deposited on smooth glass textures. The second approach was to create a transparent and conducting upconverter to be used on top of the rear reflector of a thin film Si solar cell. For that purpose, ZnO was doped with Er and Yb ions and was post-annealed under different treatments. The unique spectral properties of rare earth (RE) elements due to their electronic configuration occur as a result of their intra 4f-4f shell transitions. In the case of Er, its excitation takes places at 1500 nm and 980 nm and the upconverted photons are emitted within the Si absorption range. Moreover, codoping with Yb can enhance the Er visible emission because they cooperate together due to the matching of their energy levels for k=980 nm. As deposited ZnO doped with rare earths (RE) was found to be transparent and conducting but not luminescent. RE ions need to be surrounded by 6 oxygen in a distorted octahedron to be optically active and REs replacing zinc in the ZnO lattice do not present this symmetry; hence, a post deposition treatment is needed. When the films were post-annealed in air, visible upconversion (UC) was seen at 660 nm under 980 nm laser excitation, however, the films become almost insulating. When the films were annealed in vacuum, lower UC luminescence was achieved, and the resistivity increased 1 order of magnitude. By using CW laser radiation, the electrical properties were maintained and high UC was observed. UC came from clusters of RE06 as well as from RE203 inside or outside the matrix. When annealing in air, in vacuum or by laser radiation, oxygen from the atmosphere bound to the RE to form RE oxides and/or RE06 complexes but just laser annealing was able to preserve the conductivity while producing optically active centers. / L'objectiu d'aquesta tesi és la millora de l'eficiència de les cèl•lules solars de silici en capa prima mitjançant l'estudi de nous mètodes per a l'aprofitament de la llum solar al dispositiu. El primer mètode consisteix en texturar el substrat de vidre per dispersar la llum incident i així incrementar l'absorció en la capa activa. El mètode emprat es la texturització induïda per alumini (AIT); que es basa en una reacció de reducció no uniforme entre el vidre i una capa prima d'alumini gràcies a un tractament tèrmic. Posteriorment els productes de la reacció s'eliminen mitjançant una solució basada en àcid i el resultat és un vidre transparent i texturat. S'ha fet un estudi de la rugositat en funció dels paràmetres del procés i s'ha aconseguit obtenir rugositats controlades i uniformes en superfícies de fins a 10x 10 cm2. Diferents textures s'han provat en cèl.lules solars de silici amorf i s'ha demostrat l'eficàcia d'aquestes en la millora del corrent respecte a les mateixes cèl•lules dipositades sobre vidre pla. El segon mètode estudiat és el fenomen de l'up-conversion que consisteix en la conversió de fotons de baixa energia (E<Eg), que normalment són transmesos, en fotons d'alta energia (E>Eg) que podran ser absorbits en la zona activa; així doncs s'ha intentat fer una capa conductora, transparent i amb propietats d'up-conversion per utilitzar com a contacte per a cèl• lules solars. Per aquest propòsit s'han estudiat capes conductores i transparents d'òxid de zinc dopat amb erbi i iterbi dipositades per polvorització catòdica sobre vidre. Com que les terres rares han d'estar envoltades d'oxigen per actuar com a centres òptics actius, i en les capes de ZnO:Er:Yb no es dóna aquesta configuració, les capes s'han hagut de sotmetre a diferents tractaments tèrmics, com escalfament en aire, en buit o escalfament amb làser. Escalfant en aire o en buit s'aconsegueix obtenir up-conversion però la conductivitat disminueix notablement, en canvi, escalfant amb radiació làser es possible de mantenir les propietats elèctriques i a més, activar òpticament les terres rares.

The main objective of this thesis was to evaluate the potential impacts of alternative VO–based feed formulations on the regulation of appetite and food intake in a commercial marine aquaculture species (Senegalese sole) by uncovering some of the possible physiological regulatory mechanisms behind these processes in early developmental, as well as juvenile stages. Effects of dietary lipid level and FA composition on lipid absorption, metabolism and sensing, as well as gastrointestinal and central appetite-related peptides were analyzed, both pre– and post–prandially. Apart from gene expression, supporting morphometric, biometric, biochemical, histological and enzymatic data was also collected. During development of molecular tools, numerous transcripts were identified for several genes, most notably for the anorexigenic neuropeptide cart, for which a total of 7 transcripts—more than has been recorded in any vertebrate to date—were characterized. In juvenile sole, hepatic lipid metabolism was affected more by dietary lipid level than source, especially at fasting, where high dietary lipids promoted catabolic and suppressed anabolic pathways. On the other hand, a lower food intake was also observed in fish fed high lipid levels, but only when the lipid source was FO, which may have indicated a higher satiating effect of FO than similar amounts of VO. This could not be related to basal and post–prandial (6 h) expression of anorexigenic gastrointestinal peptides which was only affected by lipid level and lower in fish fed high–lipid diets. The expression of central appetite–regulating genes in the brain was not affected at basal levels by the diets. However, most central neuropeptides (cart1b, cart4, pomca, cckl, npy, agrp2) responded to feeding and showed changes in expression during the post–prandial phase, with only slight differences in relation to lipid level. A system for hypothalamic sensing of circulating FA was discribed in juveniles, for the first time in a marine fish. Results confirmed its sensitivity to oleic acid, previously established in trout, but also, for the first time in a vertebrate, provided evidence of activation by an n-3 PUFA (ALA). A method for quantifying live prey intake in larval fish was developed for this thesis, using fluorescent microspheres as markers. The method also enabled experiments of prey selectivity, by using different coloured microshperes to label prey from different treatmetns. While results showed that no preferance of diet was exhibited when fish were offered a choice, larvae previously grown on Artemia enriched with cod–liver oil (CLO) ingested more of their respective diet (per g body weight) compared to those fed linseed (LSO), soybean or olive oil–based diets. Larvae fed CLO also showed improved growth and survival, faster onset of metamorphosis and maturation of the intestine. Gene expression profiles of both larvae and post–larvae fed CLO stood out most from the other treatments with decreased transcript levels of genes involved in anabolic pathways, and increased of those related to phospholipid metabolism, lipoprotein secretion, lipid transport and hydrolysis. Fish fed CLO were closely followed by those fed LSO, almost catching up in terms of growth by the end of the experiment, and were closely grouped in terms of gene expression to those fed CLO, corroborating the possitive effects of enhanced phospholipid metabolism and apolipoprotein synthesis on larval performance. Peripheral peptides in larvae and post–larvae generally did not mirror their putative function or explain lower food intake in fish fed the VO diets, but fish fed CLO tended to show the most dissimilar pattern of central appetite–regulating gene expression, compared to the other dietary treatments. While this thesis provides generally more descriptive results, it can serve as a basis for future, mechanistic studies.

Tesi realitzada a l'Institut de Recerca Biomèdica de Barcelona (IRBB) / Els compostos de fòsfor han mostrat propietats úniques com a lligands per a la catàlisi asimètrica. El nostre grup de recerca ha estat dedicat a la síntesi de compostos P-estereogènics durant els darrers 5 anys. La present tesi doctoral ha estat dedicada al disseny i la síntesi de nous lligands P-estereogènics i a la seva aplicació en catàlisi asimètrica. S’ha sintetitzat una nova família de difosfines amb quiralitat a l’àtom de fòsfor anomenades ThaxPHOS. Aquests lligands han estat complexats a cobalt i s’ha estudiat les propietats dels catalitzadors obtinguts per a la reacció de Pauson-Khand asimètrica i catalítica entre norbornadiè i alquins terminals. Com a resultat d’aquest estudi s’ha obtingut les enones corresponents amb resultats sense precedents fins al moment. Seguidament s’ha desenvolupat una metodologia versàtil per a la síntesi de nous lligands P-estereogènics a partir d’aminofosfines òpticament pures. Mitjançant la hidròlisi àcida d’aminofosfines s’ha obtingut els àcids fosfinosos coresponents els quals han estat subjectes a la substitució nucleòfila a l’àtom de fòsfor. Mitjançant aquesta metodologia s’ha sintetitzat una nova família de lligands P-estereogènics. Per tal de mostrar la utilitat de la nova metodologia desenvolupada s’ha sintetitzat una nova família de lligands fosfino-oxazolina, 5, els quals han estat emprats per a la hidrogenació asimètrica catalitzada per iridi. Els catalitzadors obtinguts han mostrat una elevada activitat per a aquest tipus de reacció, donant els productes hidrogenats amb elevada selectivitat en alguns casos. Publicacions: - S. Orgué, T. León, A. Riera, X. Verdaguer, Org. Lett. 2015, 17, 250–253. - A. Flores-Gaspar, S. Orgué, A. Grabulosa, A. Riera, X. Verdaguer, Chem. Commun. 2015, 51, 1941–1944. / Phosphorus compounds have demonstrated unique properties as ligands for asymmetric catalysis. Our group has been devoted to the synthesis of P-stereogenic ligands in the last 5 years. The present doctoral thesis is devoted to the design and synthesis of new P-stereogenic ligands and its application in asymmetric catalysis. We synthesized a new family of P-stereogenic diphosphines called ThaxPHOS. These ligands were complexed to cobalt and the resulting catalysts have been studied for the catalytic and asymmetric Pauson-Khand reaction between norbornadiene and different terminal alkynes. As a result of this study the corresponding enones were obtained with unprecedented results so far. Next, we have developed a versatile method for the synthesis of new P-stereogenic ligands from optically pure aminophosphines. The acidic hydrolisis of aminophosphines was performed giving rise to phosphinous acid boranes. This compounds were used as electrophiles for nucleophilic substitutions at the P centre. Using this methodology it was synthesized a new family of P estereogenic ligands. In order to show the usefulness of the new methodology developed, it was synthesized a new family of phosphine-oxazoline ligands, 5, which have been used for iridium catalysed asymmetric hydrogenation. The catalysts obtained showed high activity for this type of reaction, giving rise to the hydrogenated products with high selectivity in some cases. Publications ; - S. Orgué, T. León, A. Riera, X. Verdaguer, Org. Lett. 2015, 17, 250–253. - A. Flores-Gaspar, S. Orgué, A. Grabulosa, A. Riera, X. Verdaguer, Chem. Commun. 2015, 51, 1941–1944.

Reproducció digital de l'original manuscrit, en fulls solts, dipositat a l'Arxiu Històric d'aquesta Universitat / Lauro Clariana Ricart (Barcelona, 1842-1916) fue un matemático e ingeniero industrial español. Obtuvo en 1873 la cátedra de matemáticas del Instituto de Tarragona. Ese mismo año se graduó de doctor en Ciencias Exactas. Fue nombrado en 1881 catedrático numerario de Cálculo Infinitesimal de la Universidad de Barcelona. De 1902 a 1907 desempeñó interinamente la cátedra de Cálculo Integral y Mecánica Racional de la Escuela de Ingenieros Industriales de esta ciudad, y desde 1909 desempeñó la de Cálculo Infinitesimal, de cuya nueva asignatura fue el iniciador. Perteneció a la Real Academia de Ciencias y Artes de Barcelona y a la de Ciencias Exactas, Físicas y Naturales de Madrid. Colaboró en diversas revistas científicas. En la Academia de Barcelona dio conferencias sobra matemáticas superiores referentes a Funciones elípticas. Ha figurado dignamente en los congresos de París, Bruselas, Múnich y Friburgo, en los que presentó numerosos trabajos sobre distintas materias. (Fuente: Wikipedia.org)