The Learning of the subject Biology in a Master in Biomedical Physics

BIOLOGY is a dynamic and fascinating science. The study of this subject is an amazing trip for all the students that have a first contact with this subject. Here, we present the development of the study and learning experience of this subject belonging to an area of knowledge that is different to the training curriculum of students who have studied Physics during their degree period. We have taken a real example, the “Elements of Biology” subject, which is taught as part of the Official Biomedical Physics Master, at the Physics Faculty, of the Complutense University of Madrid, since the course 2006/07. Its main objective is to give to the student an understanding how the Physics can have numerous applications in the Biomedical Sciences area, giving the basic training to develop a professional, academic or research career. The results obtained when we use new virtual tools combined with the classical learning show that there is a clear increase in the number of persons that take and pass the final exam. On the other hand, this new learning strategy is well received by the students and this is translated to a higher participation and a decrease of the giving the subject u

Comparison of peristrophic multiplexing and a combination of angular and peristrophic holographic multiplexing in a thick PVA/acrylamide photopolymer for data storage

Two different types of multiplexing are used to store 90 holograms at the same location in a polyvinyl alcoholacrylamide photopolymer material. In the first, the 90 holograms are stored using only peristrophic multiplexing, whereas in the second a combination of angular and peristrophic multiplexing is used. The results (diffraction efficiency and dynamic range, M#) obtained with these two multiplexing techniques are compared. With the first, the dynamic range was M# = 13 and with the second M# = 8. An exposure schedule method is used to calculate the exposure time necessary to store the holograms with a more uniform, higher diffraction efficiency.This work was supported by the “Ministerio de Educación y Ciencia (Spain)” under projects FIS2005-05881-C02-01 and FIS2005-05881-C02-02, and by the “Generalitat Valenciana” under Project GV06/172

Secuencia paleomagnética y paleolítica del Cuaternario aluvial del Bajo Guadalquivir: actualización y nuevos resultados

One proceeds to check the chronology attributed to the General Sequence of the Guadalquivir (SGG) by means of the application of the palaeomagnetic to his terraces. This one remains concentrated on more than 1.5 M.a with presence of lithic artifact of Achaelian adscription from ends of the Lower Pleistocene (0.9 M.a) until ends of the Middle Pleistocene

Influence of 4,4’-azobis (4-cyanopentanoic acid) in Transmission and Reflection Gratings Stored in a PVA/AA Photopolymer

Holographic transmission gratings with a spatial frequency of 2658 lines/mm and reflection gratings with a spatial frequency of 4553 lines/mm were stored in a polyvinyl alcohol (PVA)/acrylamide (AA) based photopolymer. This material can reach diffraction efficiencies close to 100% for spatial frequencies about 1000 lines/mm. However, for higher spatial frequencies, the diffraction efficiency decreases considerably as the spatial frequency increases. To enhance the material response at high spatial frequencies, a chain transfer agent, the 4,4’-azobis (4-cyanopentanoic acid), ACPA, is added to the composition of the material. Different concentrations of ACPA are incorporated into the main composition of the photopolymer to find the concentration value that provides the highest diffraction efficiency. Moreover, the refractive index modulation and the optical thickness of the transmission and reflection gratings were obtained, evaluated and compared to procure more information about the influence of the ACPA on them.This work was supported by the “Generalitat Valenciana” (Spain) under projects PROMETEOII/2015/015 and ISIC/2012/013 and by “Ministerio de Ciencia e Innovación” (Spain) under projects FIS2014-56100-C2-1-P and FIS2015-66570-P

Intracellular mechanisms of solar water disinfection

Solar water disinfection (SODIS) is a zero-cost intervention measure to disinfect drinking water in areas of poor access to improved water sources, used by more than 6 million people in the world. The bactericidal action of solar radiation in water has been widely proven, nevertheless the causes for this remain still unclear. Scientific literature points out that generation of reactive oxygen species (ROS) inside microorganisms promoted by solar light absorption is the main reason. For the first time, this work reports on the experimental measurement of accumulated intracellular ROS in E. coli during solar irradiation. For this experimental achievement, a modified protocol based on the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA), widely used for oxidative stress in eukaryotic cells, has been tested and validated for E. coli. Our results demonstrate that ROS and their accumulated oxidative damages at intracellular level are key in solar water disinfection

Registro de redes diente de sierra en fotopolímeros: efecto del sellante

Los fotopolímeros son unos materiales fotosensibles interesantes para el registro de elementos ópticos difractivos. No obstante el registro de perfiles de fase abruptos, como las redes de diente de sierra, presenta problemas por los rápidos cambios que tienen lugar en la superficie de estos materiales. En este trabajo se propone la utilización de sellantes con un índice de refracción promedio del fotopolímero para mejorar el registro de elementos difractivos abruptos.Financiado por Ministerio de Economía y Competitividad (FIS2011-29803-C02-01 y FIS2011-29803-C02-02), Generalitat Valenciana (PROMETEO/2011/021, ISIC/2012/013 y GV/2014/076), y Universidad de Alicante (GRE12-14)

Influencia del ACPA en la resolución y estabilidad de redes holográficas almacenadas en fotopolímeros basados en PVA/Acrilamida

Este trabajo presenta los resultados obtenidos después de almacenar redes holográficas por transmisión con una frecuencia espacial de 2663 líneas/mm, en un material basado en PVA/AA. A la composición del material se le ha incorporado un agente acortador de cadenas para mejorar su resolución espacial. Además, se ha aplicado un proceso de curado a las redes almacenadas para fijar el rendimiento en difracción y que no disminuya con el paso del tiempo.Este trabajo ha sido subvencionado por el Ministerio de Economía y Competitividad (proyectos FIS2011-29803-C02-01 y FIS2011-29803-C02-02), por la Generalitat Valenciana (proyecto PROMETEO/2011/021) y por la Universidad de Alicante (proyecto GRE09-10)

Complex diffractive optical elements stored in photopolymers

Photopolymers have been used mainly for holographic recording applications. Nowadays, the improvements made in diffusion models, simulating phase image stored in these materials, enable a wide range of complex diffractive optical elements (DOEs) to be fabricated. Concurrently, the miniaturization of spatial light modulators makes it possible to generate both symmetric and non-symmetric DOEs. We show the procedure to record different complex diffractive elements, and we study the viability to fabricate them based on photopolymers. In particular we evaluate the recording of achromatic lenses, axicons and fork gratings interesting to obtain optical vortices. To achieve this goal, we use a three-dimensional diffusion model, previously experimentally validated with the recording of diffractive lenses.Ministerio de Economía y Competitividad (Spain) FIS2017-82919-R (MINECO/AEI/FEDER, UE) and FIS2015-66570-P(MINECO/ FEDER); Generalitat Valenciana (Spain) (PROMETEO II/2015/015)

Study of influence of ACPA in PVA/AA photopolymer for holographic reflection gratings

This work pretends to optimize the standard composition of the PVA/Acrylamide photopolymer, changing its composition in order to improve its spatial resolution. To do this, a chain transfer agent, 4,4'-azobis (4-cyanopentanoic acid) (ACPA) was introduced in the photopolymer and its concentration was modified. Thus, the optimal concentration which gets obtain the maximum diffraction efficiency for high spatial frequencies was found. To quantify the improvement that occurs with the inclusion of the ACPA in the PVA/Acrylamide photopolymer, holographic reflexion gratings of 4553 lines/mm were stored. Moreover, diffraction efficiency obtained with the different concentrations of ACPA was measured to compare the obtained results.This work was supported by the “Generalitat Valenciana” (Spain) under project PROMETEO/2011/021, ISIC/2012/013 and GV/2012/099 and by “Ministerio de Ciencia e Innovación” (Spain) under projects FIS2011-29803-C02-01 and FIS2011-29803-C02-02