The characteristic cohomology class of a triangulated category

This is the final version of a series of papers uploaded in May 25, 2005. We have splitted the long last paper of the previous version in two parts to make it easier to understand. The results are essentially the same, although the presentation has changed substantially. The first three papers have not changed. This is a collection of five papers on the foundation of triangulated categories in the context of groupoid-enriched categories, termed track categories, and characteristic cohomology classes. As a main result it is shown that given an additive category A with a translation functor t: A --> A and a class V in translation cohomology H^3(A,t) then two simple properties of V imply that (A,t) is a triangulated category. The cohomology class V yields an equivalence class (B,[s]) where B is a track category with homotopy category A and [s] is the homotopy class of a pseudofunctor s: B --> B inducing t. The two properties of V correspond to natural axioms on B and s which again imply that (A,t) is a triangulated category. The five papers of this volume depend on each other by cross references, but each paper can be read independently of the others so that the reader is free to choose one of the papers to start. Each paper has its own abstract, introduction and literature.Comment: 166 pages, some diagrams do not appear correctly in the DVI fil

Synchronization in interacting Scale Free Networks

We study the fluctuations of the interface, in the steady state, of the Surface Relaxation Model (SRM) in two scale free interacting networks where a fraction $q$ of nodes in both networks interact one to one through external connections. We find that as $q$ increases the fluctuations on both networks decrease and thus the synchronization reaches an improvement of nearly $40\%$ when $q=1$. The decrease of the fluctuations on both networks is due mainly to the diffusion through external connections which allows to reducing the load in nodes by sending their excess mostly to low-degree nodes, which we report have the lowest heights. This effect enhances the matching of the heights of low-and high-degree nodes as $q$ increases reducing the fluctuations. This effect is almost independent of the degree distribution of the networks which means that the interconnection governs the behavior of the process over its topology.Comment: 13 pages, 7 figures. Added a relevant reference.Typos fixe

Transport of therapeutics across intestinal epithelium

This chapter focuses on the oral administration of therapeutics. Patients prefer oral administration because it is painless and simple to implement. [...

In vitro genome editing for testing potential gRNAs in CRISPR/Cas9 strategy

Motivation: CRISPR/Cas9 is a promising strategy that improves the efficacy of homology recombination, opening a wide number of possibilites for genome editing. The use of this technology on the reparation of single nucleotide mutations is being under investigation to recover the phenotype of a number of diseases, as the Crigler-Najjar syndrome. Methods: The genomic target sequence of the Ugt1a1 mouse gene was cloned into vectors that were designed to assess efficiency in the generation of double strand brakes (DSB) by engineered nucleases. We have designed different sgRNAs targeting this genomic region. The vectors were transfected into Hek293 together with a plasmid expressing the Cas9 nucelase and the sgRNA, generating a DSB in the target sequence. After recombination, the inactive luciferase gene recovers activity, which is proportional to the cutting efficiency of the nuclease. Then, luciferase and T7 assays were used to determine the activity of gRNAs to target the specific genome locus. Results: Depending on the DNA sequence where is located the gRNA and, specially, the PAM sequences, we have obtained different results on the activity of our gRNAs. However, different factors, as the type of cells transfected or the vectors used, can affect the final activity of the gRNAs and thus, the whole CRISPR/Cas9 activity.Conclusions: With this project, it has been demonstrated the importance of a good design and optimization of the protocols to choose the most efficient gRNAs for CRISPR/Cas9 machinery, as well as in the vectors used to synthetize all the components needed

Osteoma osteoide en falange de la mano

Presentamos un caso de osteoma osteoide localizado en una falange de la mano. La clínica de meses de evolución y los hallazgos radiográficos de la RMN, nos llevaron al diagnóstico. Realizamos una extirpación en bloque de la lesión, con confirmación histológica del diagnóstico. Los síntomas desaparecieron tras la intervención y después de un año no hay evidencia de recidiva.We present a case of osteoid osteoma located in a phalanx of the hand. The clinic of months of evolution, the radiographics findings and the MRI, carried us to the diagnostic. We accomplish a removal in block of the injury, with histological confirmation of the diagnostic. The symptomes dissappeared after the operation and after a year there is no evidence from recurrence

Synchronization in Scale Free networks: The role of finite size effects

Synchronization problems in complex networks are very often studied by researchers due to its many applications to various fields such as neurobiology, e-commerce and completion of tasks. In particular, Scale Free networks with degree distribution $P(k)\sim k^{-\lambda}$, are widely used in research since they are ubiquitous in nature and other real systems. In this paper we focus on the surface relaxation growth model in Scale Free networks with $2.5< \lambda <3$, and study the scaling behavior of the fluctuations, in the steady state, with the system size $N$. We find a novel behavior of the fluctuations characterized by a crossover between two regimes at a value of $N=N^*$ that depends on $\lambda$: a logarithmic regime, found in previous research, and a constant regime. We propose a function that describes this crossover, which is in very good agreement with the simulations. We also find that, for a system size above $N^{*}$, the fluctuations decrease with $\lambda$, which means that the synchronization of the system improves as $\lambda$ increases. We explain this crossover analyzing the role of the network's heterogeneity produced by the system size $N$ and the exponent of the degree distribution.Comment: 9 pages and 5 figures. Accepted in Europhysics Letter

Quantitative study of valence and configuration interaction parameters of the Kondo semiconductors CeM2Al10 (M = Ru, Os and Fe) by means of bulk-sensitive hard x-ray photoelectron spectroscopy

The occupancy of the 4f^n contributions in the Kondo semiconductors CeM2Al10(M = Ru, Os and Fe) has been quantitatively determined by means of bulk-sensitive hard x-ray photoelectron spectroscopy (HAXPES) on the Ce 3d core levels. Combining a configuration interaction scheme with full multiplet calculations allowed to accurately describe the HAXPES data despite the presence of strong plasmon excitations in the spectra. The configuration interaction parameters obtained from this analysis -- in particular the hybridization strength V_eff and the effective f binding energy Delta_f -- indicate a slightly stronger exchange interaction in CeOs2Al10 compared to CeRu2Al10, and a significant increase in CeFe2Al10. This verifies the coexistence of a substantial amount of Kondo screening with magnetic order and places the entire CeM2Al10 family in the region of strong exchange interactions.Comment: 9 pages, 4 figures, submitted to Physical Review

The SCOFF-c: Psychometric properties of the Catalan version in a Spanish adolescent sample

Objective The objective of this study is to validate the Catalan version of the SCOFF questionnaire with a community sample of adolescents. Method This study used a community sample of 954 participants (475 girls and 479 boys; aged between 10.9 and 17.3 years and from the city of Barcelona) and a risk group of 78 participants (35 men and 43 women; derived from the community sample) that have exceeded ≥95 percentile in at least two of the three scales of the Eating Disorders Inventory-2 (EDI-2): Drive for Thinness, Bulimia, and Body Dissatisfaction. Results There were significant differences in total SCOFF scores across gender and school grades. The SCOFF best cutoff point was 2 (sensitivity=73.08%; specificity=77.74%). Concurrent validity with the EDI-2 varied between low and moderate. The reliability of the SCOFF questionnaire was moderate. Exploratory factor analysis of the SCOFF questionnaire showed a two-factor structure for the total sample and for girls, and one factor for boys. Conclusion The best cutoff point for this community sample is 2. The data suggest that the SCOFF questionnaire could be a useful screening questionnaire to enable the detection of groups possibly at risk for eating disorders among adolescent Spanish community samples