Charged Particle-like Branes in ABJM: A Summary

We study the effect of adding lower dimensional brane charges to the 't Hooft monopole, di-baryon and baryon vertex configurations in AdS_4 x CP^3. We show that these configurations capture the background fluxes in a way that depends on the induced charges, requiring additional fundamental strings to cancel the worldvolume tadpoles. The dynamics reveal that the charges must lie inside some interval, a situation familiar from the baryon vertex in AdS_5 x S^5 with charges. For the baryon vertex and the di-baryon the number of fundamental strings must also lie inside an allowed interval. Some ideas about the existence of these bounds in relation to the stringy exclusion principle are given.Comment: 6 pages. Contribution to the proceedings of the XVIth European Workshop on String Theory, Madrid, Spain, June 14-18 2010; based on a talk given by N. Gutierre

Hints of 5d Fixed Point Theories from Non-Abelian T-duality

In this paper we investigate the properties of the putative 5d fixed point theory that should be dual, through the holographic correspondence, to the new supersymmetric AdS(6) solution constructed in Lozano et al. This solution is the result of a non-Abelian T-duality transformation on the known supersymmetric AdS(6) solution of massive Type IIA. The analysis of the charge quantization conditions seems to put constraints on the global properties of the background, which, combined with the information extracted from considering probe branes, suggests a 2-node quiver candidate for the dual CFT.Comment: v2, typos corrected, comments added, to appear in JHE

Slow Extraction of Charged Ion Pulses from the REXEBIS

The Isotope mass Separator On-Line DEvice (ISOLDE) facility located at CERN, produces and transports Radioactive Ion Beams (RIBs) at low or high energy through the REX/HIE-ISOLDE linear accelerator, for nuclear physics, astrophysics, solid-state physics and applied-physics purposes. Increasing the charge state of the ions is a prerequisite for efficient acceleration and is accomplished by an Electron Beam Ion Source (REXEBIS). For more effective event discrimination at the experimental detectors, such as the MINIBALL spectrometer, it is advantageous to increase the pulse width of extracted ions from this EBIS. A Slow Extraction scheme is presented which uses a function comprised of discrete voltage steps to apply the extraction potential to the EBIS trap barrier. This function effectively stretches the pulse length of both stable and radioactive ion beams, with different mass-to-charge ratios and provides for extracted pulse widths in the millisecond range. Key operational parameters of the EBIS impacting the average ionic temperature and its axial energy spread are discussed, in order to anticipate changes in the resulting ion pulse time structures during experimental runs.Comment: 17th International Conference on Ion Sources (ICIS17, October 2017, Geneva

Assessing the effect of source code characteristics on changeability

Maintenance is the phase of the software lifecycle that comprises any modification after the delivery of an application. Modifications during this phase include correcting faults, improving internal attributes, as well as adapting the application to different environments. As application knowledge and architectural integrity degrade over time, so does the facility with which changes to the application are introduced. Thus, eliminating source code that presents characteristics that hamper maintenance becomes necessary if the application is to evolve. We group these characteristics under the term Source Code Issues. Even though there is support for detecting Source Code Issues, the extent of their harmfulness for maintenance remains unknown. One of the most studied Source Code Issue is cloning. Clones are duplicated code, usually created as programmers copy, paste, and customize existing source code. However, there is no agreement on the harmfulness of clones. This thesis proposes and follows a novel methodology to assess the effect of clones on the changeability of methods. Changeability is the ease with which a source code entity is modified. It is assessed through metrics calculated from the history of changes of the methods. The impact of clones on the changeability of methods is measured by comparing the metrics of methods that contain clones to those that do not. Source code characteristics are then tested to establish whether they are endemic of methods whose changeability decay increase when cloned. In addition to findings on the harmfulness of cloning, this thesis contributes a methodology that can be applied to assess the harmfulness of other Source Code Issues. The contributions of this thesis are twofold. First, the findings answer the question about the harmfulness of clones on changeability by showing that cloned methods are more likely to change, and that some cloned methods have significantly higher changeability decay when cloned. Furthermore, it offers a characterization of such harmful clones. Second, the methodology provides a guide to analyze the effect of Source Code Characteristics in changeability; and therefore, can be adapted for other Source Code Issues

Multistate Study to Determine the Presence of Salmonella spp. in Farm Animals and their Environment

Salmonella is the second most common cause of foodborne infection in the Unites States (US). It is estimated that about 1.4 million people suffer from salmonellosis a year in the US with an estimated annual cost of $2.9 billion. Human cases of salmonellosis are often related to the consumption of raw meat and unpasteurized milk and milk products. Whereas the fecal-oral contamination is well established at farm level, less in known about the role of the environment on the Salmonella survival. The objective of this study was to compare isolation of Salmonella in farm animals and their environment based on spatial, temporal, and environmental factors to provide population-based epidemiological information that can be used in assessing risk and development risk management strategies. Samples were collected from 12 different locations in 5 states (Tennessee, Alabama, North Carolina, California and Washington). Samples originated from dairy cows, beef cattle and swine herds. Environmental samples (n=360) and rectal swabs (n=1200) were analyzed using BAM modified protocols. Salmonella positives were characterized with Riboprinter® and Pulsed-Field Gel Electrophoresis using PvuII and XbaI restriction enzymes. Salmonella was most frequently isolated from swine, the animals being the major reservoir, with an isolation of fecal materials of 11.9%, followed by rectal swabs (8.8%) and feed (7.7%). For dairy cows and beef cattle, the major reservoir of Salmonella was the environment, especially the feed (3.1%), followed by soil samples (2.0%). The most common serotypes isolated from swine were S. Anatum, S. Javiana, S. Newington, and S. Worthington. The most common serotypes found in dairy cows were S. Anatum, S. Newington and S. Javiana, whereas only two serotypes were isolated from beef cattle, S. Anatum and S. Newington. The Simpson’s diversity index was calculated for Riboprinter (0.86) and PFGE (0.98). This data indicates significant diversity among the Salmonella isolated, but we were able to find regional and spatial differences among the Salmonella isolates. Breaking the contamination cycle between the animals, their environment, and management practices to control swine fecal materials will be essential to reduce the isolation of Salmonella in farm animals

Supersymmetric AdS_6 via T-duality

We present a new supersymmetric AdS_6 solution of type IIB supergravity with SU(2) isometry. Through the AdS/CFT correspondence, this has potentially very interesting implications for 5d fixed point theories. This solution is the result of a non-Abelian T-duality on the known supersymmetric AdS_6 solution of massive IIA. The SU(2) R-symmetry is untouched, leading to sixteen supercharges and preserved supersymmetry.Comment: 4 pages, published versio