Majorana vs Pseudo-Dirac Neutrinos at the ILC

Neutrino masses could originate in seesaw models testable at colliders, with light mediators and an approximate lepton number symmetry. The minimal model of this type contains two quasi-degenerate Majorana fermions forming a pseudo-Dirac pair. An important question is to what extent future colliders will have sensitivity to the splitting between the Majorana components, since this quantity signals the breaking of lepton number and is connected to the light neutrino masses. We consider the production of these neutral heavy leptons at the ILC, where their displaced decays provide a golden signal: a forward-backward charge asymmetry, which depends crucially on the mass splitting between the two Majorana components. We show that this observable can constrain the mass splitting to values much lower than current bounds from neutrinoless double beta decay and natural loop corrections.Comment: 16 pages, 5 figures; v2: Minor changes, version accepted for publication in EPJ

JCLAL: A Java framework for active learning

Active Learning has become an important area of research owing to the increasing number of real-world problems which contain labelled and unlabelled examples at the same time. JCLAL is a Java Class Library for Active Learning which has an architecture that follows strong principles of object-oriented design. It is easy to use, and it allows the developers to adapt, modify and extend the framework according to their needs. The library offers a variety of active learning methods that have been proposed in the literature. The software is available under the GPL license

N-(2-Furylcarbon­yl)piperidine-1-carbo­thio­amide

The title compound, C11H14N2O2S, was synthesized from furoyl isothio­cyanate and piperidine in dry acetone. The thio­urea group is in the thio­amide form. The thio­urea group makes a dihedral angle of 53.9 (1)° with the furan carbonyl group. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯O hydrogen bonds, forming one-dimensional chains along the c axis. An intramolecular N—H⋯O hydrogen bond is also present

Diagramas de predominancia, de frost y de pourbaix: tres contextos para desarrollar competencias en procesos de óxido-reducción

En el aprendizaje de la Química es necesario desarrollar algunas competencias (interpretación, argumentación, proposición) relacionadas con el conocimiento de la reactividad de varias especies inorgánicas en los procesos de oxidaciónreducción y la habilidad para predecir y manejar adecuadamente los productos de reacción. Las tendencias termodinámicas (estabilidad o reactividad) de diferentes especies de elementos en tales procesos pueden entenderse mediante la construcción e interpretación de diagramas termodinámicos (diagramas de predominancia, de Frost y de Pourbaix). El presente trabajo muestra una revisión actualizada y una discusión integrada de estos tres tipos de diagramas, considerándolos como tres contextos pedagógicos importantes en Química

Genotoxic and Cytotoxic Studies of Beta-Sitosterol and Pteropodine in Mouse

Beta-sitosterol (BS) and pteropodine (PT) are constituents of various plants with pharmacological activities potentially useful to man. The chemicals themselves possess biomedical properties related to the modulation of the immune and the nervous systems, as well as to the inflammatory process. Therefore, safety evaluation of the compounds is necessary in regard to their probable beneficial use in human health. The present study evaluates their genotoxic and cytotoxic potential by determining the capacity of the compounds to induce sister chromatid exchanges (SCE), or to alter cellular proliferation kinetics (CPK) and the mitotic index (MI) in mouse bone marrow cells. Besides, it also determines their capacity to increase the rate of micronucleated polychromatic erythrocytes (MNPE) in peripheral mouse blood, and the relationship polychromatic erythrocytes/normochromatic erythrocytes (PE/NE) as an index of cytotoxicity. For the first assay, four doses of each compound were tested: 200, 400, 600, and 1000 mg/kg in case of BS, and 100, 200, 300, and 600 mg/kg for PT. The results in regard to both agents showed no SCE increase induced by any of the tested doses, as well as no alteration in the CPK, or in the MI. With respect to the second assay, the results obtained with the two agents were also negative for both the MNPE and the PE/NE index along the daily evaluation made for four days. In the present study, the highest tested dose corresponded to 80% of the LD(50) obtained for BS and to 78% in the case of PT. The results obtained establish that the studied agents have neither genotoxic nor cytotoxic effect on the model used, and therefore they encourage studies on their pharmacological properties

1-Furoyl-3-[3-(trifluoro­meth­yl)phen­yl]thio­urea

The title compound, C13H9F3N2O2S, crystallizes with two independent mol­ecules in the asymmetric unit. The central thio­urea core is roughly coplanar with the furan and benzene rings, showing O—C—N—C(S) torsion angles of 2.3 (4) and −11.4 (2)° and (S)C—N—C—C torsion angles of −2.4 (4) and −28.8 (4)°, respectively, in the two independent mol­ecules. The trans–cis geometry of the thio­urea fragment is stabilized by an intra­molecular N—H⋯O hydrogen bond between the H atom of the cis thio­amide and the carbonyl O atom. In the crystal structure, inter­molecular N—H⋯S hydrogen bonds form centrosymmetric dimers extending along the b axis