Gametic and somatic embryogenesis through in vitro anther culture of different Citrus genotypes

Abstract: In vitro tissue culture represents a useful technique for advancing Citrus breeding and propagation. Among in vitro regeneration systems, anther culture is commonly used to produce haploids and doubled haploids for a fast-track producing homozygous lines, in comparison with the traditional self-pollination approach, which involves several generations of selfing. In addition, anthers culture can produce somatic embryos that can also be used for clonal propagation. In this study, two thermal shocks were applied to the anthers of six Citrus genotypes (two clementine and four sweet oranges), just after they were put in culture. The response obtained was different depending on the genotype: both clementines, namely Hernandina and Corsica, produced homozygous and triploid regenerants (microspore-derived embryos), whereas all of the analyzed regenerants from sweet oranges, three cultivars of Tarocco and Moro, produced heterozygous and diploid regenerants similar to the parental genotypes (somatic embryos)

IMPORTÂNCIA DA DISCIPLINA ADMINISTRAÇÃO NOS CURSOS DE ENGENHARIA DA FURB

Este artigo tem como objetivo verificar a importância do ensino de administração nos cursos de engenharia tendo como base a formação e perfil do engenheiro requerido pela sociedade atualmente. A formação almejada é de um profissional de capacidade humanística, crítica e reflexiva elevada. Atualmente se espera do profissional de engenharia, não só o conhecimento técnico propriamente dito, pois já se passa pelo pressuposto que isso é uma condição inerente do profissional com uma boa formação, mas sim um conhecimento mais aprofundado de ciências humanas, sociais e gerenciais, sintetizando uma formação generalista. Acredita-se que para conseguir este perfil o profissional precisa ter em sua grade curricular básica, disciplinas de cunho humanístico social, que é o caso exemplificado neste artigo, as disciplinas de administração. Assim, como as demais áreas do conhecimento, o ensino de engenharia passa por uma constante busca de aperfeiçoamento com mudanças em seus currículos, para atender as necessidades atuais das novas tecnologias, demandas provenientes da sociedade e mercado de trabalho. Partindo do pressuposto que a inclusão das disciplinas de cunho de ciências humanas e sociais nas grades curriculares dos cursos de engenharia pode contribuir para dar suporte ao profissional em formação, analisou-se através de um questionário estruturado a disciplina de administração dos cursos de Engenharia Civil, Engenharia Química, Engenharia Industrial Elétrica e Engenharia de Telecomunicação da Universidade Regional de Blumenau, no segundo semestre de 2004. O questionamento principal é se o aluno percebe a importância deste tipo de disciplina na sua formação profissional. O resultado obtido é que o aluno, após ter quase a totalidade do conteúdo programado, consegue verificar esta importância, mas não consegue fazer ligações desta disciplina com outras de seu curso, ou seja a interdisciplinaridade dos conteúdos na visão do aluno não é alcançada em sua totalidade. Por outro lado, o perfil do docente é de uma pessoa capaz de transmitir sua experiência e trocá-las com os alunos, haja visto que muitos alunos já trabalham em sua futura área de atuaçã

Constraint-based runtime prediction of SLA violations in service orchestrations

Service compositions put together loosely-coupled component services to perform more complex, higher level, or cross-organizational tasks in a platform-independent manner. Quality-of-Service (QoS) properties, such as execution time, availability, or cost, are critical for their usability, and permissible boundaries for their values are defined in Service Level Agreements (SLAs). We propose a method whereby constraints that model SLA conformance and violation are derived at any given point of the execution of a service composition. These constraints are generated using the structure of the composition and properties of the component services, which can be either known or empirically measured. Violation of these constraints means that the corresponding scenario is unfeasible, while satisfaction gives values for the constrained variables (start / end times for activities, or number of loop iterations) which make the scenario possible. These results can be used to perform optimized service matching or trigger preventive adaptation or healing

Phase diagram for non-axisymmetric plasma balls

Plasma balls and rings emerge as fluid holographic duals of black holes and black rings in the hydrodynamic/gravity correspondence for the Scherk-Schwarz AdS system. Recently, plasma balls spinning above a critical rotation were found to be unstable against m-lobed perturbations. In the phase diagram of stationary solutions the threshold of the instability signals a bifurcation to a new phase of non-axisymmetric configurations. We find explicitly this family of solutions and represent them in the phase diagram. We discuss the implications of our results for the gravitational system. Rotating non-axisymmetric black holes necessarily radiate gravitational waves. We thus emphasize that it would be important, albeit possibly out of present reach, to have a better understanding of the hydrodynamic description of gravitational waves and of the gravitational interaction between two bodies. We also argue that it might well be that a non-axisymmetric m-lobed instability is also present in Myers-Perry black holes for rotations below the recently found ultraspinning instability.Comment: 1+22 pages, 3 figures. v2: minor corrections and improvements, matches published versio

Logarithmic Corrections to Rotating Extremal Black Hole Entropy in Four and Five Dimensions

We compute logarithmic corrections to the entropy of rotating extremal black holes using quantum entropy function i.e. Euclidean quantum gravity approach. Our analysis includes five dimensional supersymmetric BMPV black holes in type IIB string theory on T^5 and K3 x S^1 as well as in the five dimensional CHL models, and also non-supersymmetric extremal Kerr black hole and slowly rotating extremal Kerr-Newmann black holes in four dimensions. For BMPV black holes our results are in perfect agreement with the microscopic results derived from string theory. In particular we reproduce correctly the dependence of the logarithmic corrections on the number of U(1) gauge fields in the theory, and on the angular momentum carried by the black hole in different scaling limits. We also explain the shortcomings of the Cardy limit in explaining the logarithmic corrections in the limit in which the (super)gravity description of these black holes becomes a valid approximation. For non-supersymmetric extremal black holes, e.g. for the extremal Kerr black hole in four dimensions, our result provides a stringent testing ground for any microscopic explanation of the black hole entropy, e.g. Kerr/CFT correspondence.Comment: LaTeX file, 50 pages; v2: added extensive discussion on the relation between boundary condition and choice of ensemble, modified analysis for slowly rotating black holes, all results remain unchanged, typos corrected; v3: minor additions and correction

Performance of prototype BTeV silicon pixel detectors in a high energy pion beam

The silicon pixel vertex detector is a key element of the BTeV spectrometer. Sensors bump-bonded to prototype front-end devices were tested in a high energy pion beam at Fermilab. The spatial resolution and occupancies as a function of the pion incident angle were measured for various sensor-readout combinations. The data are compared with predictions from our Monte Carlo simulation and very good agreement is found.Comment: 24 pages, 20 figure

Beam Test Results of the BTeV Silicon Pixel Detector

The results of the BTeV silicon pixel detector beam test carried out at Fermilab in 1999-2000 are reported. The pixel detector spatial resolution has been studied as a function of track inclination, sensor bias, and readout threshold.Comment: 8 pages of text, 8 figures, Proceedings paper of Pixel 2000: International Workshop on Semiconductor Pixel Detectors for Particles and X-Rays, Genova, June 5-8, 200

Beam Test of BTeV Pixel Detectors

The silicon pixel vertex detector is one of the key elements of the BTeV spectrometer. Detector prototypes were tested in a beam at Fermilab. We report here on the measured spatial resolution as a function of the incident angles for different sensor-readout electronics combinations. We compare the results with predictions from our Monte Carlo simulation.Comment: 7 pages, 5 figures, Invited talk given by J.C. Wang at "Vertex 2000, 9th International Workshop on Vertex Detectors", Michigan, Sept 10-15, 2000. To be published in NIM

Issues with the Material Point Method for geotechnical modelling, and how to address them

The Material Point Method (MPM) for solid mechanics was first proposed by Sulsky and coworkers in the 1990s. Since then it has been developing a growing band of followers not least because of its ability to handle large deformation problems with ease. This feature has more recently come to the notice of geotechnical researchers who have plenty of problems to solve involving large deformations. It is clear from recent publications, however, that many geotechnical researchers have found difficulties with the use of the MPM in a number of areas. In this paper we visit three of these problem areas and highlight solutions we have developed. It is to be hoped that this can remove some of the roadblocks to the use and further development of the MPM for geotechnical problems in future

Adapting Decision DAGs for Multipartite Ranking

European Conference, ECML PKDD 2010, Barcelona, Spain, September 20-24, 2010Multipartite ranking is a special kind of ranking for problems in which classes exhibit an order. Many applications require its use, for instance, granting loans in a bank, reviewing papers in a conference or just grading exercises in an education environment. Several methods have been proposed for this purpose. The simplest ones resort to regression schemes with a pre- and post-process of the classes, what makes them barely useful. Other alternatives make use of class order information or they perform a pairwise classi cation together with an aggregation function. In this paper we present and discuss two methods based on building a Decision Directed Acyclic Graph (DDAG). Their performance is evaluated over a set of ordinal benchmark data sets according to the C-Index measure. Both yield competitive results with regard to stateof- the-art methods, specially the one based on a probabilistic approach, called PR-DDA