University of Córdoba (Spain)

About: University of Córdoba (Spain) is a education organization based out in Cordova, Spain. It is known for research contribution in the topics: Population & Catalysis. The organization has 12006 authors who have published 22998 publications receiving 537842 citations. The organization is also known as: University of Córdoba (Spain) & Universidad de Córdoba.

Metal-Oxide-Free Methylammonium Lead Iodide Perovskite-Based Solar Cells: the Influence of Organic Charge Transport Layers

Abstract: Metal-oxide-free methylammonium lead iodide perovskite-based solar cells are prepared using a dual-source thermal evaporation method. This method leads to high quality reproducible films with large crystal domain sizes allowing for an in depth study of the effect of perovskite film thickness and the nature of the electron and hole blocking layers on the device performance. The power conversion efficiency increases from 4.7% for a device with only an organic electron blocking layer to almost 15% when an organic hole blocking layer is also employed. In addition to the in depth study on small area cells, larger area cells (approx. 1 cm(-2)) are prepared and exhibit efficiencies in excess of 10%.

Memetic algorithms for continuous optimisation based on local search chains

Abstract: Memetic algorithms with continuous local search methods have arisen as effective tools to address the difficulty of obtaining reliable solutions of high precision for complex continuous optimisation problems. There exists a group of continuous local search algorithms that stand out as exceptional local search optimisers. However, on some occasions, they may become very expensive, because of the way they exploit local information to guide the search process. In this paper, they are called intensive continuous local search methods. Given the potential of this type of local optimisation methods, it is interesting to build prospective memetic algorithm models with them. This paper presents the concept of local search chain as a springboard to design memetic algorithm approaches that can effectively use intense continuous local search methods as local search operators. Local search chain concerns the idea that, at one stage, the local search operator may continue the operation of a previous invocation, starting from the final configuration (initial solution, strategy parameter values, internal variables, etc.) reached by this one. The proposed memetic algorithm favours the formation of local search chains during the memetic algorithm run with the aim of concentrating local tuning in search regions showing promise. In order to study the performance of the new memetic algorithm model, an instance is implemented with CMA-ES as an intense local search method. The benefits of the proposal in comparison to other kinds of memetic algorithms and evolutionary algorithms proposed in the literature to deal with continuous optimisation problems are experimentally shown. Concretely, the empirical study reveals a clear superiority when tackling high-dimensional problems.

Changes in protein expression profiles in bivalve molluscs (Chamaelea gallina) exposed to four model environmental pollutants.

Abstract: Proteomics has been used in the clam Chamaelea gallina as a preliminary screening of changes in protein expression caused by pollutants, potentially useful as new biomarkers. Clams were exposed in water for seven days to four model contaminants, Aroclor 1254, copper(II), tributyltin (TBT), and arsenic(III), and cytosolic fractions were initially analyzed by two-dimensional (2-D) electrophoresis in 7 cm IPG strips (pH 4-7). On average, about 1000 spots were resolved and altered expression was qualitatively detected in 9-26 spots per treatment. Aroclor 1254, Cu(II) and As(III) had a mainly upregulating effect, in contrast to TBT. Altered protein expression was confirmed in 18 cm gels (at narrow pH ranges). The 15 spots more drastically altered were excised and analyzed by mass spectrometry (MS), and four proteins were identified. Aroclor 1254 and Cu(II) upregulated putative isoforms of tropomyosin and light chain of myosin. Actin was downregulated by Aroclor and Cu(II) but upregulated by TBT and As(III), while the opposite behavior was shown by a truncated actin form, homologous to the Drosophila act87E gene product. The exclusive identification of cytoskeletal proteins could reflect their relative abundance, their prevalence in databases in molluscs, or their role as major targets of pollutant-related oxidative stress.