Modificació de flavonoides naturals per al seu ús com a medicaments

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2021, Tutor: Xavier Ariza PiquerObesity is a new problem today due to the increased consumption of energy-dense foods along with a sedentary lifestyle. That is why some studies have been carried out to discover new anti-obesity drugs. It has been found that flavones, a type of molecule in the flavonoid family, are important components of many natural plants with important protective effects, such as antioxidant, anti-inflammatory activity against many diseases and the increase of fat burning by different ways depending on the specific molecule. In this work, we have focused on the synthesis and characterization of five chrysin derivates: 5-hydroxy-7-methoxyflavone, 5,7-dimethoxyflavone, 6-bromo-5,7-dimethoxyflavone, 6,8-dibromo-5,7-hydroxyflavone and 6-benzyl-5,7-dimethoxyflavone. These compounds could be useful for the study of browning of fat cells because it is supposed that they allow to convert WAT (white adipose tissue) to BAT (brown adipose tissue) which could help in different diseases and upgrade the fat burning of our bodie

Implementing and testing optical transceivers for fiber access networks

New fiber-to-the-Home access networks require low cost broadband transceivers capable of sharing an optical cable infrastructure. In this TFG different types of broadband optical transmitters and receivers for fiber access networks will be analyzed, assembled and tested: intensity modulated transmitter, phase modulated transmitter, direct detection receiver and coherent receiver.Los sistemas ópticos coherentes están desarrollando un papel muy importante en las telecomunicaciones actuales. Aunque el precio de estos sistemas sea elevado, parece ser que pueden ser una buena opción de cara a las futuras redes de acceso. Este proyecto propone estudiar, diseñar i testear hardware que pueda ser implementado en futuras ONU?sy OLT?s. Dos trasmisores low-cost, más precisamente, un DFB y un DEML serán diseñados, ensamblados y testeados. Además, se diseñará y testeará un demodulador AM simple. Diversos experimentos han sido diseñados para comprobar las características más relevantes de cada sistema para ver si pueden ser candidatos potenciales par ales futuras redes de acceso.Els sistemes òptics coherent estan desenvolupant un paper molt important en les telecomunicacions actuals. Encara que el preu d?aquests sistemes sigui elevat, sembla ser que poden ser una bona opció per les futures xarxes d?accés. Aquest projecta proposa estudiar, dissenyar i testejar hardware que pugui ser implementat en futures ONU?s i OLT?s. Dos transmissors low-cost, més precisament, un DFB i un DEML seran dissenyats, muntats i testejats. A més també, es dissenyarà un demodulador AM senzill. Diversos experiments han estat dissenyats per tal de comprovar les característiques més rellevants de cada sistema, per tal de veure si poden ser candidats potencials per poder ser part de les futures xarxes d?accés

Determinación del coeficiente de difusión de colorantes directos y su relación con la concentración del electrolito.

Este trabajo consta de dos partes. La primera de ellas consiste en establecer una técnica adecuada para las determinaciones de los coeficientes de difusión, y la segunda parte es el estudio de la influencia del electrolito en el valor del coeficiente de difusión y su relación con las propiedades tintóreas.Peer Reviewe

Unraveling deformation mechanisms around FCC and BCC nanocontacts through slip trace and pileup topography analyses

Nanocontact loadings offer the potential to investigate crystal plasticity from surface slip trace emissions and distinct pileup patterns where individual atomic terraces arrange into hillocks and symmetric rosettes. Our MD simulations in FCC Cu and Al nanocontacts show development of specific dislocation interception, cross-slip and twin annihilation mechanisms producing traces along characteristic and directions. Although planar slip is stabilized through subsurface dislocation interactions, highly serrated slip traces always predominate in Al due to the advent of cross-slip of the surfaced population of screw dislocations, leading to intricate hillock morphologies. We show that the distinct wavy hillocks and terraces in BCC Ta and Fe nanocontacts are due to dislocation double-kinking and outward spreading of surfaced screw segments, which originate from dislocation loops induced by twin annihilation and twin-mediated nucleation processes in the subsurface. Increasing temperature favors terrace formation in BCCs whereas the enhancement of surface decorations in FCCs limits hillock definition. It is found that material bulging against the indenter-tip is a distinctive feature in nanocontact plasticity associated with intermittent defect bursts. Bulging is enhanced by recurrent slip traces introduced throughout the contact surface, as in the case of the strongly linear defect networks in FCC Al, and by specific twin arrangements at the vicinity of BCC nanocontacts. Defect patterning also produces surface depressions in the form of vertexes around FCC nanoimprints. While the rosette morphologies are consistent with those assessed experimentally in greater FCC and BCC imprints, local bulging promoted during tip removal becomes more prominent at the nanoscale.Peer ReviewedPostprint (author's final draft