168 research outputs found

    Arqueología Medieval en Guipúzcoa. Estado actual y perspectivas de futuro.

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    La Arqueología Medieval en Guipúzcoa tiene una larga trayectoria. Iniciada a principios de siglo, las actuaciones se han sucedido hasta el presente, de manera intermitente. En la actualidad presenta una evolución acelerada, ligada, sobre todo, a las intervenciones de salvamento. El futuro de la misma, parece especialmente vinculado a este tipo de actuaciones arqueológicas

    La inscripción funeraria de época romana de la ermita de San Pedro. (Zegama, Gipuzkoa).

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    El descubrimiento de una nueva inscripción de época romana, funeraria, realizada sobre una lápida de arenisca supone una nueva fuente de conocimiento en el estudio de nuestro pasado, máxime cuando ésta se ha conservado dispuesta a los pies del altar de la ermita de San Pedro en Zegama

    Dynamical tadpoles and Weak Gravity Constraints

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    Non-supersymmetric string models are plagued with tadpoles for dynamical fields, which signal uncanceled forces sourced by the vacuum. We argue that in certain cases, uncanceled dynamical tadpoles can lead to inconsistencies with quantum gravity, via violation of swampland constraints. We describe an explicit realization in a supersymmetric toroidal Z2 × Z2 orientifold with D7-branes, where the dynamical tadpole generated by displacement of the D7-branes off its minimum leads to violation of the axion Weak Gravity Conjecture. In these examples, cancellation of dynamical tadpoles provides consistency conditions for the configuration, of dynamical nature (as opposed to the topological conditions of topological tadpoles, such as RR tadpole cancellation in compact spaces). We show that this approach provides a re-derivation of the Z-minimization criterion for AdS vacua giving the gravitational dual of a-maximization in 4d N = 1 toric quiver SCFT

    Dynamical tadpoles, stringy cobordism, and the SM from spontaneous compactification

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    We consider string theory vacua with tadpoles for dynamical fields and uncover universal features of the resulting spacetime-dependent solutions. We argue that the solutions can extend only a finite distance ∆ away in the spacetime dimensions over which the fields vary, scaling as ∆n∼T with the strength of the tadpole T. We show that naive singularities arising at this distance scale are physically replaced by ends of spacetime, related to the cobordism defects of the swampland cobordism conjecture and involving stringy ingredients like orientifold planes and branes, or exotic variants thereof. We illustrate these phenomena in large classes of examples, including AdS5×T1,1 with 3-form fluxes, 10d massive IIA, M-theory on K3, the 10d non-supersymmetric USp(32) strings, and type IIB compactifications with 3-form fluxes and/or magnetized D-branes. We also describe a 6d string model whose tadpole triggers spontaneous compactification to a semirealistic 3-family MSSM-like particle physics mode

    Instanton Induced Neutrino Majorana Masses in CFT Orientifolds with MSSM-like spectra

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    Submitted on 9 Apr 2007 (v1), last revised 25 Apr 2007 (this version, v2).-- 68 pages, 2 figures.-- v2: typos corrected, refs added.-- Published in: JHEP06(2007)011.Recently it has been shown that string instanton effects may give rise to neutrino Majorana masses in certain classes of semi-realistic string compactifications. In this paper we make a systematic search for supersymmetric MSSM-like Type II Gepner orientifold constructions admitting boundary states associated with instantons giving rise to neutrino Majorana masses and other L- and/or B-violating operators. We analyze the zero mode structure of D-brane instantons on general type II orientifold compactifications, and show that only instantons with O(1) symmetry can have just the two zero modes required to contribute to the 4d superpotential. We however discuss how the addition of fluxes and/or possible non-perturbative extensions of the orientifold compactifications would allow also instantons with Sp(2) and U(1) symmetries to generate such superpotentials. In the context of Gepner orientifolds with MSSM-like spectra, we find no models with O(1) instantons with just the required zero modes to generate a neutrino mass superpotential. On the other hand we find a number of models in one particular orientifold of the Gepner model (2,4,22,22) with Sp(2) instantons with a few extra uncharged non-chiral zero modes which could be easily lifted by the mentioned effects. A few more orientifold examples are also found under less stringent constraints on the zero modes. This class of Sp(2) instantons have the interesting property that R-parity conservation is automatic and the flavour structure of the neutrino Majorana mass matrices has a simple factorized form.The research of A.N. Schellekens was funded in part by program FP 57 of the Foundation for Fundamental Research of Matter (FOM), and Research Project FPA2005-05046 of Ministerio de Educación y Ciencia, Spain. The research by L.E. Ibáñez and A.M. Uranga has been supported by the European Commission under RTN European Programs MRTN-CT-2004-503369, MRTN-CT-2004-005105, by the CICYT (Spain), and the Comunidad de Madrid under project HEPHACOS P-ESP-00346.Peer reviewe

    Dynamical cobordism and swampland distance conjectures

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    We consider spacetime-dependent solutions to string theory models with tadpoles for dynamical fields, arising from non-trivial scalar potentials. The solutions have necessarily finite extent in spacetime, and are capped off by boundaries at a finite distance, in a dynamical realization of the Cobordism Conjecture. We show that as the configuration approaches these cobordism walls of nothing, the scalar fields run off to infinite distance in moduli space, allowing to explore the implications of the Swampland Distance Conjecture. We uncover new interesting scaling relations linking the moduli space distance and the SDC tower scale to spacetime geometric quantities, such as the distance to the wall and the scalar curvature. We show that walls at which scalars remain at finite distance in moduli space correspond to domain walls separating different (but cobordant) theories/vacua; this still applies even if the scalars reach finite distance singularities in moduli space, such as conifold points. We illustrate our ideas with explicit examples in massive IIA theory, M-theory on CY threefolds, and 10d non-supersymmetric strings. In 4d N = 1 theories, our framework reproduces a recent proposal to explore the SDC using 4d string-like solution

    Dynamical cobordism and swampland distance conjectures

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    We consider spacetime-dependent solutions to string theory models with tadpoles for dynamical fields, arising from non-trivial scalar potentials. The solutions have necessarily finite extent in spacetime, and are capped off by boundaries at a finite distance, in a dynamical realization of the Cobordism Conjecture. We show that as the configuration approaches these cobordism walls of nothing, the scalar fields run off to infinite distance in moduli space, allowing to explore the implications of the Swampland Distance Conjecture. We uncover new interesting scaling relations linking the moduli space distance and the SDC tower scale to spacetime geometric quantities, such as the distance to the wall and the scalar curvature. We show that walls at which scalars remain at finite distance in moduli space correspond to domain walls separating different (but cobordant) theories/vacua; this still applies even if the scalars reach finite distance singularities in moduli space, such as conifold points. We illustrate our ideas with explicit examples in massive IIA theory, M-theory on CY threefolds, and 10d non-supersymmetric strings. In 4d N = 1 theories, our framework reproduces a recent proposal to explore the SDC using 4d string-like solution

    An Objective Structured Clinical Examination to Assess Pharmacy Resident Performance

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    Objective: The objective was to utilize an Objective Structured Clinical Examination (OSCE) for assessment of pharmacy residents. Innovation: Post-graduate year 1 (PGY1) and post-graduate year 2 (PGY2) pharmacy residents completing multiple, local residency programs were invited to participate in an OSCE. A total of eight PGY1 residents and one PGY2 resident completed the OSCE. American Society of Health-System Pharmacists (ASHP) residency program goals were aligned for each case, which were originally developed for a fourth-year pharmacy student OSCE. Station design included outpatient and inpatient settings with patient and physician interactions. Median communication and clinical skills scores were evaluated. Critical Analysis: The OSCE allows for assessment of all residents on common scenarios. Pharmacy residents met competency requirements and demonstrated excellent communication skills. The OSCE was able to evaluate both physician-pharmacist communication and patient-pharmacist communication. Baseline performance related to the ASHP goals and objectives was not completed; however, the OSCE could highlight resident strengths and weaknesses in communication and clinical skills. The OSCE could simulate independent practice, may reduce bias, and could provide an evaluation of the resident by a patient. However, the OSCE incurs higher resource utilization, specifically monetary and time, than other assessment methods. Next Steps: The pilot study results provide a beginning for further study of OSCEs for pharmacy residents. Further study should include surveying the residency directors about use of the OSCE, a comparison of performance between the OSCE and preceptor evaluations of residents on ASHP goals and objectives, and an evaluation of OSCE implementation at different time points within the residency. Conflict of Interest We declare no conflicts of interest or financial interests that the authors or members of their immediate families have in any product or service discussed in the manuscript, including grants (pending or received), employment, gifts, stock holdings or options, honoraria, consultancies, expert testimony, patents and royalties   Type: Not
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