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Semilocal strings-a particular limit of electroweak strings-are an interesting example of a stable non-topological defect whose properties resemble those of their topological cousins, the Abrikosov-Nielsen-Olesen vortices. There is, however, one important difference: a network of semilocal strings will contain segments. These are 'dumbbells' whose ends behave almost like global monopoles that are strongly attracted to one another. While closed loops of string will eventually shrink and disappear, the segments can either shrink or grow, and a cosmological network of semilocal strings will reach a scaling regime. We discuss attempts to find a 'thermodynamic' description of the cosmological evolution and scaling of a network of semilocal strings, by analogy with well-known descriptions for cosmic strings and for monopoles. We propose a model for the time evolution of an overall length scale and typical velocity for the network as well as for its segments, and some supporting (preliminary) numerical evidence. This article is part of a discussion meeting issue 'Topological avatars of new physics'.

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We report the first observation of multiple intercommutation (more than two successive reconnections) of Abelian Higgs cosmic strings at ultrahigh collision speeds, and the formation of "kink trains" with up to four closely spaced left- or right-moving kinks, in the deep type-II regime 16 ≤ ß ≤ 64 (where ß=m(scalar)2/m(gauge)2). The minimum critical speed for double reconnection goes down from ∼0.98c at ß = 1 to ∼0.86c for ß = 64. The process leading to the second intercommutation changes with ß: it involves an expanding loop if ß ≥ 16, but only a radiation blob if 1 < ß ≤ 8. Triple reconnections are generic in the loop-mediated regime for collision parameters on the boundary between single and double reconnection. For ß = 16 we observe quadruple events. We comment on the effect of strongly repulsive core interactions on the small scale structure on the strings and their gravitational wave emission.

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The Ministry of Health and Consumer Affairs and the Autonomous Governments of Spain have designed and agreed by consensus with the sanitary professionals and major employer's organizations and Unions a Integral Health Surveillance Programme of asbestos-exposed workers, in order to assure appropriate, uniform and harmonized action throughout the national territory with relation to these workers. PROGRAM DESCRIPTION: This initiative started from the Occupational Health Working group of the Interterritorial Council, with inputs from the Asbestos Working Group of the National Occupational Safety and Health Commission. It was agreed with occupational medicine and infirmary professionals and was approved by the Health and Labour authorities. The program is organised in seven main activities. CURRENT PROGRAM STATUS: two years after the Programme approval a total of 5778 workers are included in the Registry of asbestos-exposed workers. 208 workers have COPD, 198 benign pleural disease, 8 lung cancer, 10 mesothelioma and 7 workers have other cancers possibly related to asbestos (gastric, larynx and colon cancer). REMARKS: the agreement and participation reached in this Programme allow achieving much higher coverage of occupational prevention policies than those obtained with a mere law approval, as we could see during the second year of implementation of the Programme in which the number of attended workers has doubled.

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El Ministerio de Sanidad y Consumo y las Comunidades Autónomashan diseñado y consensuado con los profesionales sanitariosy las organizaciones empresariales y sindicales representativas unPlan Integral de Vigilancia de la Salud de los Trabajadores que hanestado expuestos a Amianto, con el objetivo de garantizar una intervenciónadecuada, uniforme y armonizada de estos trabajadores entodo el territorio nacional. La elaboración del Programa partió delGrupo de Trabajo de Salud Laboral del Consejo Interterritorial, seenriqueció con las aportaciones del Grupo de Trabajo Amianto de laComisión Nacional de Seguridad y Salud en el Trabajo, fue consensuadocon los profesionales de la medicina y enfermería del trabajo,y fue aprobado por las autoridades sanitarias y laborales. El Programaconsta de siete grandes bloques de actividades. Dos años despuésde aprobado el Programa, el estado de implantación en las ComunidadesAutónomas es desigual. Las principales dificultades para supuesta en marcha se encuentran en la elaboración del Registro deexpuestos. Un total de 5.778 trabajadores están incluidos en el Registro.208 trabajadores tienen EPOC, 198 alteraciones pleurales benignas,8 cáncer de pulmón, 10 mesotelioma y 7 presentan otros cáncerescon posible relación con el amianto (gástrico, de laringe y colon). El consenso y la participación alcanzados alrededor de este Programaestán permitiendo lograr coberturas de las políticas de prevenciónde riesgos laborales muy superiores a las que se consiguen conla mera actuación institucional y elaboración de normativa, ya que ensólo los dos primeros años de implantación del Programa se ha duplicadoel número de trabajadores atendidos

The Ministry of Health and Consumer Affairs and the AutonomousGovernments of Spain have designed and agreed by consensuswith the sanitary professionals and major employer's organizationsand Unions a Integral Health Surveillance Programme ofasbestos-exposed workers, in order to assure appropriate, uniformand harmonized action throughout the national territory with relationto these workers. Program description: this initiative startedfrom the Occupational Health Working group of the InterterritorialCouncil, with inputs from the Asbestos Working Group of theNational Occupational Safety and Health Commission. It was agreedwith occupational medicine and infirmary professionals and wasapproved by the Health and Labour authorities. The program isorganised in seven main activities. Current Program status: twoyears after the Programme approval a total of 5,778 workers areincluded in the Registry of asbestos-exposed workers. 208 workershave COPD, 198 benign pleural disease, 8 lung cancer, 10 mesotheliomaand 7 workers have other cancers possibly related toasbestos (gastric, larynx and colon cancer). Remarks: the agreementand participation reached in this Programme allow achievingmuch higher coverage of occupational prevention policies than those obtained with a mere law approval, as we could see duringthe second year of implementation of the Programme in which thenumber of attended workers has doubled

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We present a superstring-inspired version of D-term inflation that does not lead to cosmic string formation and appears to satisfy the current cosmic microwave background constraints. It differs from minimal D-term inflation by a second pair of charged superfields that makes the strings nontopological (semilocal). The strings are also Bogomol'nyi-Prasad-Sommerfield strings, so the scenario is expected to survive supergravity corrections. The second pair of charged superfields arises naturally in several brane and conifold scenarios, but its effect on cosmic string formation had not been noticed so far.

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We analyze the stability of global O(3) monopoles in the infinite cutoff (or scalar mass) limit. We obtain the perturbation equations and prove that the spherically symmetric solution is classically stable (or neutrally stable) to axially symmetric, square integrable, or power-law decay perturbations. Moreover, we show that, in spite of the existence of a conserved topological charge, the energy barrier between the monopole and the vacuum is finite even in the limit where the cutoff is taken to infinity. This feature is specific of global monopoles and independent of the details of the scalar potential.