Inside the Zoo: Captive Giraffes’ Changes in Social Ties Throughout Membership Variations

Many animals live in gregarious, fission-fusion societies where group size and composition are continually changing. Despite this, many studies have suggested that captive animals are capable of maintaining long term social bonds with others. In captive giraffes, effects on their social bonds during membership transitions have not been studied thoroughly, however, prior research does show that social bonds are a defining factor in non-captive animals. Captive giraffe social network patterns were investigated at the Jacksonville Zoo and Botanical Gardens using all occurrence behavioral data. Based on previous research, I hypothesized that when one of the individuals in the group was removed, the previous significant social ties would remain significant. Specifically, I expected there would not be significant changes within the group in how they interact. Furthermore, I expected same age groups and same sex groups to be defining variables across the two data sets, in regard to social organization. The data was analyzed using R’s package StatNet and SNA to develop their social network patterns and determine if there is any significance. There were significant social ties found within some members of the group before Sir Isaac was removed, but after his removal no significant ties were found. There was also a significant difference in the rate of interactions between same sex individuals when the two datasets were compared. Furthermore, there was significant reciprocity within both datasets. These results imply that there were in fact differences in individual social ties with the removal of Sir Isaac. Limitations include that this was a case study and there was no breeding male. The aforementioned results hint at the fact that captive giraffes are not exhibiting the same behaviors as wild giraffes

Trilepton Signal for Supersymmetry at the Fermilab Tevatron Revisited

Within a wide class of models, the LEP2 lower limit of 95 GeV on the chargino mass implies gluinos are heavier than $\sim$300 GeV. In this case electroweak \tw_1\twb_1 and \tw_1\tz_2 production are the dominant SUSY processes at the Tevatron, and the extensively examined isolated trilepton signal from \tw_1\tz_2 production assumes an even greater importance. We update our previous calculations of the SUSY reach of luminosity upgrades of the Fermilab Tevatron in this channel incorporating ({\it i}) decay matrix elements in the computation of the momenta of leptons from chargino and neutralino decays, ({\it ii}) the trilepton background from $W^*Z^*$ and $W^*\gamma^*$ production which, though neglected in previous analyses, turns out to be the dominant background, and finally, ({\it iii}) modified sets of cuts designed to reduce these new backgrounds and increase the range of model parameters for which the signal is observable. We show our improved projections for the reach for SUSY of both the Fermilab Main Injector and the proposed TeV33 upgrade. We also present opposite sign same flavor dilepton invariant mass distributions as well as the $p_T$ distributions of leptons in SUSY trilepton events, and comment upon how the inclusion of decay matrix elements impacts upon the Tevatron reach, as well as upon the extraction of neutralino masses.Comment: final version to coincide with published manuscrip

XRound : A reversible template language and its application in model-based security analysis

Successful analysis of the models used in Model-Driven Development requires the ability to synthesise the results of analysis and automatically integrate these results with the models themselves. This paper presents a reversible template language called XRound which supports round-trip transformations between models and the logic used to encode system properties. A template processor that supports the language is described, and the use of the template language is illustrated by its application in an analysis workbench, designed to support analysis of security properties of UML and MOF-based models. As a result of using reversible templates, it is possible to seamlessly and automatically integrate the results of a security analysis with a model. (C) 2008 Elsevier B.V. All rights reserved

LHC Reach for Gauge Mediated Supersymmetry Breaking Models Via Prompt Photon Channels

We evaluate the supersymmetry reach of the Large Hadron Collider within the gauge-mediated low energy supersymmetry breaking framework, assuming that a neutralino is the second lightest sparticle and that it decays promptly into a gravitino which escapes detection. We find that the maximum reach is obtained via a search for inclusive \gamma\gamma+\eslt events coming dominantly from chargino and neutralino production. Assuming an integrated luminosity of 10~$fb^{-1}$, we find that LHC experiments will be able to probe values of the model parameter \Lambda \alt 400 TeV, corresponding to $m_{\tg} \leq 2.8$ TeV. A measure of the model parameter $\Lambda$ may be possible from the photon $p_T$ spectrum.Comment: 10 page Revtex file plus 4 EPS figure