Brane Cosmologies without Orbifolds

We study the dynamics of branes in configurations where 1) the brane is the edge of a single anti-de Sitter (AdS) space and 2) the brane is the surface of a vacuum bubble expanding into a Schwarzschild or AdS-Schwarzschild bulk. In both cases we find solutions that resemble the standard Robertson-Walker cosmologies although in the latter, the evolution can be controlled by a mass parameter in the bulk metric. We also include a term in the brane action for the scalar curvature. This term adds a contribution to the low energy theory of gravity which does not need to affect the cosmology but which is necessary for the surface of the vacuum bubble to recover four dimensional gravity.Comment: 13 pages, uses harvmac, vacuum bubble case corrected and expanded, references adde

Workforce Investment Act (WIA) Reauthorization Proposals in the 113th Congress: Comparison of Major Features of Current Law and S.1356

The Workforce Investment Act of 1998 (WIA; P.L. 105-220) is the primary federal program that supports workforce development activities, including job search assistance, career development, and job training. WIA established the One-Stop delivery system as a way to co-locate and coordinate the activities of multiple employment programs for adults, youth, and various targeted subpopulations. The delivery of these services occurs primarily through more than 3,000 One- Stop career centers nationwide. WIA includes four main titles that cover employment and training services, adult education and literacy services, the employment service, and vocational rehabilitation services for individuals with disabilities. The authorizations for appropriations for most programs under WIA expired at the end of FY2003. Since that time, WIA programs have been funded through the annual appropriations process. The Senate Committee on Health, Education, Labor, and Pensions (HELP) held a markup of S. 1356 (the Workforce Investment Act of 2013) on July 31, 2013, and ordered the bill reported by a vote of 18 to 3. S. 1356 would reauthorize WIA through 2018. S. 1356 would maintain the One-Stop delivery system established by WIA but would make changes to the programs, services, and governing structure of WIA, through changes to Workforce Investment Boards (WIBs), state plan requirements, national programs, and alignment and coordination provisions across all titles. Some of the major changes include the adoption of primary indicators of performance across all WIA titles, the requirement of a Unified State Plan that includes all core programs, the authorization of innovation and replication grants, greater emphasis on economic and employment outcomes for adult education programs, and expanded services for youth and students with disabilities. This report provides a comparison of major themes in current WIA and in S. 1356

A 2 TeV WRW_R, Supersymmetry, and the Higgs Mass

A recent ATLAS search for diboson resonances and a CMS search for $eejj$ resonances which both show excesses with significance around 3 sigma have generated interest in $SU(2)_R$ gauge extensions of the Standard Model with a $W'$ mass around 2 TeV. We investigate the possibility that an $SU(2)_R$ gauge extension of the MSSM compatible with an explanation of the diboson anomaly might give rise to a significant enhancement of the Higgs mass above the MSSM tree level bound $m_{h, \text{tree}} < 90 \; \text{GeV}$ due to non-decoupling D-terms. This model contains a vector-like charge -1/3 $SU(2)_R$ singlet quark for each generation which mixes significantly with the $SU(2)_R$ doublet quarks, affecting the $W_R$ phenomenology. We find that it is possible to achieve $m_{h, \text{tree}} > 110 \; \text {GeV}$, and this requires that the $Z'$ mass is close to 3 TeV.Comment: 18 pages + appendices, 6 figure

Hidden-Sector Higgs Bosons at High-Energy Electron-Positron Colliders

The possibility of a scalar messenger that can couple the Standard Model (SM) to a hidden sector has been discussed in a variety of contexts in the literature in recent years. We consider the case that a new scalar singlet charged under an exotic spontaneously broken Abelian gauge symmetry mixes weakly with the SM Higgs resulting in two scalar mass states, one of which has heavily suppressed couplings to the SM particles. Previous phenomenological studies have focussed on potential signatures for such a model at the Large Hadron Collider (LHC). However, there are interesting regions of the parameter space in which the heavier Higgs state would be out of reach for LHC searches if its mass is greater than 1 TeV. We therefore investigate the discovery potential for such a particle at a 3 TeV electron-positron collider, which is motivated by the recent developments of the Compact Linear Collider (CLIC). We find that such an experiment could substantially extend our discovery reach for a heavy, weakly coupled Higgs boson, and we discuss three possible search channels.Comment: 14 pages, 8 Figures. Published as an LCD Not

Directed evolution of Vibrio fischeri LuxR for increased sensitivity to a broad spectrum of acyl-homoserine lactones

LuxR-type transcriptional regulators play key roles in quorum-sensing systems that employ acyl-homoserine lactones (acyl-HSLs) as signal molecules. These proteins mediate quorum control by changing their interactions with RNA polymerase and DNA in response to binding their cognate acyl-HSL. The evolutionarily related LuxR-type proteins exhibit considerable diversity in primary sequence and in their response to acyl-HSLs having acyl groups of differing length and composition. Little is known about which residues determine acyl-HSL specificity, and less about the evolutionary time scales required to forge new ones. To begin to examine such issues, we have focused on the LuxR protein from Vibrio fischeri, which activates gene transcription in response to binding its cognate quorum signal, 3-oxohexanoyl-homoserine lactone (3OC6HSL). Libraries of luxR mutants were screened for variants exhibiting increased gene activation in response to octanoyl-HSL (C8HSL), with which wild-type LuxR interacts only weakly. Eight LuxR variants were identified that showed a 100-fold increase in sensitivity to C8HSL; these variants also displayed increased sensitivities to pentanoyl-HSL and tetradecanoyl-HSL, while maintaining a wild-type or greater response to 3OC6HSL. The most sensitive variants activated gene transcription as strongly with C8HSL as the wild type did with 3OC6HSL. With one exception, the amino acid residues involved were restricted to the N-terminal, 'signal-binding' domain of LuxR. These residue positions differed from critical positions previously identified via 'loss-of-function' mutagenesis. We have demonstrated that acyl-HSL-dependent quorum-sensing systems can evolve rapidly to respond to new acyl-HSLs, suggesting that there may be an evolutionary advantage to maintaining such plasticity

Preserving a Space for Science in an Age of Democracy

How should scientific advice be incorporated into the political decision-making process? Harry Collins explores this question in his review of The Paradox of Scientific Authority

Can consumer research panels form an effective part of the cancer research community?

The North Trent Cancer Research Network’s Consumer Research Panel (NTCRN CRP) was established in December 2001 by the Academic Unit of Supportive Care at the University of Sheffield. In three years, the CRP has succeeded in nurturing a climate of sustainable consumer involvement within the NTCRN and this has become embedded in the culture of the network. Furthermore, the panel have championed a sustainable development of consumer involvement in health and social care research by testing new ground and forging a new way of working between health professionals and patients and carers. The CRP model has been held up as an example to other cancer networks, with new panels being set up around the country to emulate its success. This paper describes the Sheffield model of patient and public involvement and using the eight key principles of successful consumer involvement in research, identified in a recent paper by Telford et al (2003), provides a useful framework for analysing the work of the Panel. This demonstrates how consumers and professionals can inform each other to work constructively and synergistically to achieve impressive research results. The need for measurable outcomes to assess the impact and effect of consumer involvement is finally explored

The extended ROSAT-ESO Flux Limited X-ray Galaxy Cluster Survey (REFLEX II) IV. X-ray Luminosity Function and First Constraints on Cosmological Parameters

The X-ray luminosity function is an important statistic of the census of galaxy clusters and an important means to probe the cosmological model of our Universe. Based on our recently completed REFLEX II cluster sample we construct the X-ray luminosity function of galaxy clusters for several redshift slices from $z = 0$ to $z = 0.4$ and discuss its implications. We find no significant signature of redshift evolution of the luminosity function in the redshift interval. We provide the results of fits of a parameterized Schechter function and extensions of it which provide a reasonable characterization of the data. Using a model for structure formation and galaxy cluster evolution we compare the observed X-ray luminosity function with predictions for different cosmological models. For the most interesting constraints for the cosmological parameters $\Omega_m$ and $\sigma_8$ we obatain $\Omega_m \sim 0.27 \pm 0.03$ and $\sigma_8 \sim 0.80 \pm 0.03$ based on the statistical uncertainty alone. Marginalizing over the most important uncertainties, the normalisation and slope of the $L_X - M$ scaling relation, we find $\Omega_m \sim 0.29 \pm 0.04$ and $\sigma_8 \sim 0.77 \pm 0.07$ ($1\sigma$ confidence limits). We compare our results with those of the SZ-cluster survey provided by the PLANCK mission and we find very good agreement with the results using PLANCK clusters as cosmological probes, but we have some tension with PLANCK cosmological results from the microwave background anisotropies. We also make a comparison with other cluster surveys. We find good agreement with these previous results and show that the REFLEX II survey provides a significant reduction in the uncertainties compared to earlier measurements.Comment: Submitted for publication to Astronomy and Astrophysics, 15 pages, 17 figure

Anomaly Detection for Resonant New Physics with Machine Learning

Despite extensive theoretical motivation for physics beyond the Standard Model (BSM) of particle physics, searches at the Large Hadron Collider (LHC) have found no significant evidence for BSM physics. Therefore, it is essential to broaden the sensitivity of the search program to include unexpected scenarios. We present a new model-agnostic anomaly detection technique that naturally benefits from modern machine learning algorithms. The only requirement on the signal for this new procedure is that it is localized in at least one known direction in phase space. Any other directions of phase space that are uncorrelated with the localized one can be used to search for unexpected features. This new method is applied to the dijet resonance search to show that it can turn a modest 2 sigma excess into a 7 sigma excess for a model with an intermediate BSM particle that is not currently targeted by a dedicated search.Comment: Replaced with short PRL version. 7 pages, 2 figures. Revised long version will be submitted separatel