Eliminating ambiguities for quantum corrections to strings moving in AdS4×CP3

We apply a physical principle, previously used to eliminate ambiguities in quantum corrections to the two-dimensional kink, to the case of spinning strings moving in AdS4×CP3, thought of as another kind of two-dimensional soliton. We find that this eliminates the ambiguities and selects the result compatible with AdS/CFT, providing a solid foundation for one of the previous calculations, which found agreement. The method can be applied to other classical string «solitons.» © 2013 World Scientific Publishing Company.

Notes on the pure spinor b ghost

In this work, a particular BRST-exact class of deformations of the b ghost in the non-minimal pure spinor formalism is investigated and the impact of this construction in the N= 2 ĉ = 3 topological string algebra is analysed. As an example, a subclass of deformations is explicitly shown, where the U (1) current appears in a conventional form, involving only the ghost number currents. Furthermore, a c ghost like composite field is introduced, but with an unusual construction. © 2013 SISSA, Trieste, Italy.

Search for microscopic black holes in pp collisions at √s=8 TeV

A search for microscopic black holes and string balls is presented, based on a data sample of pp collisions at √s=8 TeV recorded by the CMS experiment at the Large Hadron Collider and corresponding to an integrated luminosity of 12 fb-1. No excess of events with energetic multiparticle final states, typical of black hole production or of similar new physics processes, is observed. Given the agreement of the observations with the expected standard model background, which is dominated by QCD multijet production, 95% confidence level limits are set on the production of semiclassical or quantum black holes, or of string balls, corresponding to the exclusions of masses below 4.3 to 6.2 TeV, depending on model assumptions. In addition, model-independent limits are set on new physics processes resulting in energetic multiparticle final states. [Figure not available: see fulltext.] © 2013 CERN for the benefit of the CMS collaboration.

Cytogenetic analysis of Phyllomedusa distincta Lutz, 1950 (2n = 2x = 26), P. tetraploidea Pombal and Haddad, 1992 (2n = 4x = 52), and their natural triploid hybrids (2n = 3x = 39) (Anura, Hylidae, Phyllomedusinae)

Background: Natural polyploidy has played an important role during the speciation and evolution of vertebrates, including anurans, with more than 55 described cases. The species of the Phyllomedusa burmeisteri group are mostly characterized by having 26 chromosomes, but a karyotype with 52 chromosomes was described in P. tetraploidea. This species was found in sintopy with P. distincta in two localities of São Paulo State (Brazil), where triploid animals also occur, as consequence of natural hybridisation. We analyse the chromosomes of P. distincta, P. tetraploidea, and their triploid hybrids, to enlighten the origin of polyploidy and to obtain some evidence on diploidisation of tetraploid karyotype.Results: Phyllomedusa distincta was 2n = 2x = 26, whereas P. tetraploidea was 2n = 4x = 52, and the hybrid individuals was 2n = 3x = 39. In meiotic phases, bivalents were observed in the diploid males, whereas both bivalents and tetravalents were observed in the tetraploid males. Univalents, bivalents or trivalents; metaphase II cells carrying variable number of chromosomes; and spermatids were detected in the testis preparations of the triploid males, indicating that the triploids were not completely sterile. In natural and experimental conditions, the triploids cross with the parental species, producing abnormal egg clutches and tadpoles with malformations. The embryos and tadpoles exhibited intraindividual karyotype variability and all of the metaphases contained abnormal constitutions. Multiple NORs, detected by Ag-impregnation and FISH with an rDNA probe, were observed on chromosome 1 in the three karyotypic forms; and, additionally, on chromosome 9 in the diploids, mostly on chromosome 8 in the tetraploids, and on both chromosome 8 and 9 in the triploids. Nevertheless, NOR-bearing chromosome 9 was detected in the tetraploids, and chromosome 9 carried active or inactive NORs in the triploids. C-banding, base-specific fluorochrome stainings with CMA3 and DAPI, FISH with a telomeric probe, and BrdU incorporation in DNA showed nearly equivalent patterns in the karyotypes of P. distincta, P. tetraploidea, and the triploid hybrids.Conclusions: All the used cytogenetic techniques have provided strong evidence that the process of diploidisation, an essential step for stabilising the selective advantages produced by polyploidisation, is under way in distinct quartets of the tetraploid karyotype. © 2013 Gruber et al.; licensee BioMed Central Ltd.

Chameleonic inflation

We attempt to incorporate inflation into a string theory realization of the chameleon mechanism. Previously, it was found that the volume modulus, stabilized by the supersymmetric potential used by Kachru, Kallosh, Linde and Trivedi (KKLT) and with the right choice of parameters, can generically work as a chameleon. In this paper, we ask whether inflation can be realized in the same model. We find that we need a large extra dimensions set-up, as well as a semi-phenomenological deformation of the Kähler potential in the quantum region. We also find that an additional KKLT term is required so that there are now two pieces to the potential, one which drives inflation in the early universe, and one which is responsible for chameleon screening at late times. These two pieces of the potential are separated by a large flat desert in field space. The scalar field must dynamically traverse this desert between the end of inflation and today, and we find that this can indeed occur under the right conditions. © 2013 SISSA, Trieste, Italy.

Chameleons on the racetrack

We modify the ansatz for embedding chameleon scalars in string theory proposed in [1] by considering a racetrack superpotential with two KKLT-type exponentials e ia instead of one. This satisfies all experimental constraints, while also allowing for the chameleon to be light enough on cosmological scales to be phenomenologically interesting. © 2013 SISSA, Trieste, Italy.

Morfometria da bacia hidrográfica do rio Bobo no Estado de Nariño, Colômbia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação das condições críticas para o surgimento de Aflatoxina na cadeia de processamento de amendoim (Arachis hypogaea L.)

Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE

Detecção de falhas estruturais usando sensores e atuadores piezelétricos e algoritmos genéticos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O papel da metáfora/analogia no ensino de ciências: uma abordagem semiótica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estruturas geômetro-diferenciais na superfície da corda bosônica

Pós-graduação em Física - IFT

Transcrição musical: um estudo critíco do repertório para instrumentos de cordas dedilhadas

Pós-graduação em Música - IA

Sistemas com dois geradores supersimétricos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise do comportamento dinâmico de um rotor vertical através do método dos elementos finitos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de um conversor estático controlado por PWM para luminária de iluminação púbica com LEDs

Pós-graduação em Engenharia Mecânica - FEG