Ultrafast transient absorption spectroscopy: principles and applications

The study of photophysical and photochemical processes crosses the interest of many fields of research in physics, chemistry and biology. In particular, the photophysical and photochemical reactions, after light absorption by a photosynthetic pigment-protein complex, are among the fastest events in biology, taking place on timescales ranging from tens of femtoseconds to a few nanoseconds. Among the experimental approaches developed for this purpose, the advent of ultrafast transient absorption spectroscopy has become a powerful and widely used technique.[1,2] Focusing on the process of photosynthesis, it relies upon the efficient absorption and conversion of the radiant energy from the Sun. Chlorophylls and carotenoids are the main players in the process. Photosynthetic pigments are typically arranged in a highly organized fashion to constitute antennas and reaction centers, supramolecular devices where light harvesting and charge separation take place. The very early steps in the photosynthetic process take place after the absorption of a photon by an antenna system, which harvests light and eventually delivers it to the reaction center. In order to compete with internal conversion, intersystem crossing, and fluorescence, which inevitably lead to energy loss, the energy and electron transfer processes that fix the excited-state energy in photosynthesis must be extremely fast. In order to investigate these events, ultrafast techniques down to a sub-100 fs resolution must be used. In this way, energy migration within the system as well as the formation of new chemical species such as charge-separated states can be tracked in real time. This can be achieved by making use of ultrafast transient absorption spectroscopy. The basic principles of this notable technique, instrumentation, and some recent applications to photosynthetic systems[3] will be described. Acknowledgements M. Moreno Oliva thanks the MINECO for a “Juan de la Cierva-Incorporación” research contract. References [1] U. Megerle, I. Pugliesi, C. Schriever, C.F. Sailer and E. Riedle, Appl. Phys. B, 96, 215 – 231 (2009). [2] R. Berera, R. van Grondelle and J.T.M. Kennis, Photosynth. Res., 101, 105 – 118 (2009). [3] T. Nikkonen, M. Moreno Oliva, A. Kahnt, M. Muuronen, J. Helaja and D.M. Guldi, Chem. Eur. J., 21, 590 – 600 (2015).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Direct healthcare costs of diabetes mellitus patients in Spain

Objectives. To estimate the healthcare resources spent by diabetic patients in Spain during the year 2002. Methods. The present work is a cost-of-illness study. Direct healthcare costs were estimated using rates of DM, based on primary and secondary sources of information. A range of prevalence from 5% to 6% of the adult population was determined. The total cost was composed of six items: insulin and oral hypoglycemic agents; other drugs; disposable and consumable goods (glucose test strips, needles and syringes); hospitalization; primary care visits; visits to specialists. Results. The estimated direct cost of DM during the year 2002 ranges from (euros)2.4 billion to (euros)2.67 billion. Hospital costs had the highest weight ((euros)933 million) in the total, followed by non-insulin, non-hypoglycemic-agent drugs ((euros)777-932 million). Much lower are the costs of insulin and oral hypoglycemic agents ((euros)311 million), primary care visits ((euros)181-272 million), specialized visits ((euros)127-145 million) and disposable elements ((euros)70-81 million). The per-diabetic, per-year cost ranges between (euros)1,290 to 1,476. Discussion. Despite our rather conservative approach to the issue, our findings demonstrate the high direct healthcare costs of diabetic patients. Likewise, they illustrate the magnitude of the costs of treatment of DM-related complications

Are Drinkers Prone To Engage In Risky Sexual Behaviors?

Sexually transmitted diseases pose an important public health problem around the world. Although many studies have explored the link between alcohol use and risky sexual practices, the unobserved differences among individuals make it difficult to assess whether the associations are casual in nature. In order to overcome these difficulties, we have obtained data from the Spanish Health and Sexual Behavior Survey (2003) in order to analyze risky sexual behaviors using four alternative methodologies: controlling results with a rich set of variables; identifying the impact of alcohol use while assuming there is an identical selection outcome for observed and unobserved variables; estimating alcohol consumption and risky sexual behaviors simultaneously based on instrumental variables; and using reduced-form equations to analyze the impact of alcohol prices and other alcohol policies on the likelihood of risky intercourse. We provide empirical evidence that alcohol abuse might increase the probability of risky sex and, more importantly, different alcohol policies are not only effective tools for reducing alcohol demand but also for controlling risky sexual behaviors.alcohol; sexually transmitted diseases; unobserved individual heterogeneity.

Estudio de los costes directos sanitarios de los pacientes con diabetes mellitus en España

Objetivo. Estimar el consumo de recursos sanitarios empleados en prevención y el tratamiento de pacientes con Diabetes Mellitus (DM) en España en el año 2002. Métodos. Estudio de coste de la enfermedad. Los costes directos sanitarios se estimaron mediante un enfoque de prevalencia recurriendo a fuentes tanto primarias como secundarias. Se estableció un arco de prevalencia que oscila entre el 5% y el 6% de la población adulta española. El coste total se desagregó en seis partidas: coste de insulinas y antidiabéticos orales; coste de otros fármacos; coste de consumibles (tiras reactivas más agujas y jeringuillas); coste de las hospitalizaciones; consultas de las consultas de Atención Primaria; coste de las consultas de Atención Especializada. Resultados. El coste directo estimado de los pacientes con DM oscila entre los 2.400 y los 2.675 millones de euros. Las partidas de mayor peso fueron los gastos hospitalarios (933 millones de euros) seguidos del coste de otros fármacos distintos de insulina y antidiabéticos orales (777-932 millones de euros). A continuación figura el coste de insulina y antidiabéticos orales (311 millones de euros), consultas de Atención Primaria (181-272 millones de euros), consultas de Atención Especializada (127-145 millones de euros) y consumibles (70-81 millones de euros). El coste por paciente y año varía, en función de los supuestos asumidos, entre los 1.289 y los 1.476 euros anuales. Discusión. A pesar de haber sido adoptado un enfoque conservador, se demuestra que en torno a los pacientes diabéticos se concentra un elevado coste directo sanitario. Asimismo, se pone de manifiesto la importancia del coste de la prevención y el tratamiento de las complicaciones crónicas asociadas a la diabetes

Novel U-Shaped D-A-D π-conjugated Systems with Mechanochromic Properties: An Experimental and Theoretical Vibrational Spectroscopic Investigation

Π-conjugated compounds have been widely studied in the last few decades due to their huge field of application in organic electronics. Specifically, stimuli-responsive Π-conjugated materials which are sensitive to external stimulus (i.e., temperature, pressure, etc) have several uses like sensors, probes and security inks, for example.1 In this work, we study two U-shape Donor-Acceptor-Donor (D-A-D) systems that are found to exhibit interesting thermal- and pressure-dependent properties. 2 They consist on two different conformers of phenothiazine-dibenzo[a,j]phenazine-phenothiazine which differs from the position of the phenothiazine respect to the dibenzophenzaine central core. Compound 1R is the equatorial-equatorial conformer and 1Y is the axial-axial conformer (Figure 1). The dibenzophenzaine group acts as an electron-acceptor whereas the phenothiazine unit acts as an electron-donor. It has been reported that this U-shape D-A-D compound shows a multi-active color changing in 3 steps and their luminescence changes with temperature, pressure and acid exposition.2 In this work, we aim to elucidate how the external stimuli (i.e. temperature, pressure, acid ambient) affects the molecular structure at both intra- and intermolecular level. To this end, we use UV-Vis absorption, Raman (Figure 1) and Infrared spectroscopy experiments in combination with DFT calculations.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Increase of the energy available for snow ablation in the Pyrenees (1959–2020) and its relation to atmospheric circulation

Midlatitude mountain snowpacks are highly vulnerable to climate warming. Past and future hydroclimate changes require a thorougout knowledge of snow ablation physical processes and the associate climate drivers

Principios básicos de Evaluación Económica de Intervenciones Sanitarias

The objective of this article is to present the general concepts associated with economic evaluations of health interventions. These elements are part of the basic information that must be present in any study and, therefore, should be considered when designing or interpreting any evaluation. Likewise, the article focuses on the objective pursued by this type of analyses, which is none other than to provide information, focused on the dimension of efficiency (cost-effectiveness), in the decision-making processes.El objetivo de este artículo es presentar los conceptos generales asociados a los estudios de evaluación económica de intervenciones sanitarias. Dichos elementos forman parte de la información básica que debe estar presente en cualquier estudio y, por tanto, deben ser tenidos en cuenta a la hora del diseño o la interpretación de cualquier evaluación. Asimismo, se incide en el objeto que persiguen este tipo de análisis, que no es otro sino aportar información, centrada en la dimensión de la eficiencia (coste-efectividad), en los procesos de toma de decisiones

Theoretical understanding of the increment of upon protonation of pyridine peripheral octupolar molecules: Toward nonlinear optical sensors

6 pages, 6 tables, 4 figures.In this article, we present a computational study of the nonlinear optical properties of pyridine-based octupolar molecules in their neutral and fully triprotonated states. The effect of the core substitution and the degree of conjugation with the periphery has been also established and confirms the possibility of fine-tuning the nonlinear optical response. Computations involving the time-dependent density-functional theory approach serve to further explore the existence of excited states with nonzero dipole moment. From these results, the origin of the high second-order nonlinear optical activity upon protonation is addressed.The present work was supported in part by the Dirección General de Enseñanza Superior DGES, MEC, Spain through research Project Nos. CTQ2006-14987-C02-01 and CTQ2005-01368. The authors are also indebted to Junta de Andalucía and Gobierno de Aragón Spain for funding their research groups FQM-0159 and E39. M.C.R.D. is grateful to the MEC/Fulbright for her Postdoctoral Fellowship at the Georgia Institute of Techology. J.C. is grateful to the MEC of Spain for an I3 professorship position of Chemistry at the University of Málaga and M.M.O. acknowledges the MEC for a personal grant.Peer reviewe

Pérdidas de productividad laboral ocasionadas por los tumores en España

En el presente trabajo se estiman los costes indirectos (pérdidas de productividad laboral) ocasionados en España por los tumores, y en particular por cuatro tipos concretos: mama, cérvix, próstata y colon. Además de los costes que originan su tratamiento y prevención, las enfermedades generan otro tipo de costes que no siempre se tienen en cuenta. El objetivo del presente trabajo es identificar, medir y valorar una parte de estos costes en el caso de uno de los grupos de enfermedades que más muertes causan en España. Finalmente, se avanza una selección de las actuaciones sanitarias factibles sobre los tumores estudiados para los que están estudiados ratios de eficiencia