A No Black Hole Theorem

We show that one cannot put a stationary (extended) black hole inside certain gravitating flux-tubes. This includes an electric flux-tube in five-dimensional Einstein-Maxwell theory, as well as the standard flux-branes of string theory. The flux always causes the black hole to grow indefinitely. One finds a similar restriction in a Kaluza-Klein setting where the higher dimensional spacetime contains no matter.Comment: 20 pages, 4 figures. v2: reference adde

Characterization of Retinal Structure in ATF6-Associated Achromatopsia.

PurposeMutations in six genes have been associated with achromatopsia (ACHM): CNGA3, CNGB3, PDE6H, PDE6C, GNAT2, and ATF6. ATF6 is the most recent gene to be identified, though thorough phenotyping of this genetic subtype is lacking. Here, we sought to test the hypothesis that ATF6-associated ACHM is a structurally distinct form of congenital ACHM.MethodsSeven genetically confirmed subjects from five nonconsanguineous families were recruited. Foveal hypoplasia and the integrity of the ellipsoid zone (EZ) band (a.k.a., IS/OS) were graded from optical coherence tomography (OCT) images. Images of the photoreceptor mosaic were acquired using confocal and nonconfocal split-detection adaptive optics scanning light ophthalmoscopy (AOSLO). Parafoveal cone and rod density values were calculated and compared to published normative data as well as data from two subjects harboring CNGA3 or CNGB3 mutations who were recruited for comparative purposes. Additionally, nonconfocal dark-field AOSLO images of the retinal pigment epithelium were obtained, with quantitative analysis performed in one subject with ATF6-ACHM.ResultsFoveal hypoplasia was observed in all subjects with ATF6 mutations. Absence of the EZ band within the foveal region (grade 3) or appearance of a hyporeflective zone (grade 4) was seen in all subjects with ATF6 using OCT. There was no evidence of remnant foveal cone structure using confocal AOSLO, although sporadic cone-like structures were seen in nonconfocal split-detection AOSLO. There was a lack of cone structure in the parafovea, in direct contrast to previous reports.ConclusionsOur data demonstrate a near absence of cone structure in subjects harboring ATF6 mutations. This implicates ATF6 as having a major role in cone development and suggests that at least a subset of subjects with ATF6-ACHM have markedly fewer cellular targets for cone-directed gene therapies than do subjects with CNGA3- or CNGB3-ACHM

Intensive Archaeological Survey of the East Crystal Falls Parkway (CR 272) Improvements Project, From US 183 to US 183A, Williamson County, Texas

PROJECT TITLE: Intensive Archaeological Survey of the East Crystal Falls Parkway (CR 272) Improvements Project, From US 183 to US 183A, Williamson County, Texas LOCATION: The project is located in southwestern Williamson County roughly 1.5 miles east of the City of Leander, Texas. The project begins at US 183 and runs northeastward terminating at US 183A. The project area is located on the Leander, Texas USGS 7.5-minute topographic quadrangle map. PURPOSE OF WORK: The project sponsor is fulfilling regulatory requirements in compliance with the Texas Antiquities Code and Section 106 of the National Historic Preservation Act. PROJECT SPONSOR: Texas Department of Transportation PROJECT LANDOWNER: City of Leander, Texas INSTITUTION CONDUCTING INVESTIGATION: SWCA Environmental Consultants PRINCIPAL INVESTIGATOR: Mary Jo Galindo SWCAPROJECT NUMBER: 15525-AUS. TXDOT CSJ: 0914-05-138 TEXAS ANTIQUITIES PERMIT: 5373 PERSONNEL INVOLVED IN FIELDWORK: Christian Hartnett (8 hours-archaeological field supervisor) and Abigail Peyton (8 hours-archaeological technician) PERSONNEL INVOLVED IN REPORT PREPARATION: Christian Hartnett (32 hours-report preparation), Abigail Peyton (5 hours-report preparation) and Carol Carpenter (2 hours-cartographic work). PROJECT SCOPE AND SUMMARY: The County Road (CR) CR 272 Improvements Project is approximately 1.1 miles long, 110 feet wide, and maximally 3 to 4 feet deep. The project will include a railroad crossing upgrade and other intersection, signal, and safety improvements. SWCA conducted an archaeological background review and intensive pedestrian survey of the project area to determine if any significant archaeological resources would be impacted by the proposed project. DATE OF WORK: August 20, 2009. NUMBER OF ACRES SURVEYED: Approximately 13.5 acres NUMBER OF SITES: None. CURATION: No artifacts were collected, thus nothing was curated. SUMMARY OF RESULTS AND RECOMMENDATIONS: No archaeological resources were identified during the course of fieldwork. Based on these investigations, no further archaeological work is ecommended for the proposed CR 272 Improvements Project

Rotating Resonator-Oscillator Experiments to Test Lorentz Invariance in Electrodynamics

In this work we outline the two most commonly used test theories (RMS and SME) for testing Local Lorentz Invariance (LLI) of the photon. Then we develop the general framework of applying these test theories to resonator experiments with an emphasis on rotating experiments in the laboratory. We compare the inherent sensitivity factors of common experiments and propose some new configurations. Finally we apply the test theories to the rotating cryogenic experiment at the University of Western Australia, which recently set new limits in both the RMS and SME frameworks [hep-ph/0506074].Comment: Submitted to Lecture Notes in Physics, 36 pages, minor modifications, updated list of reference

Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.2–2.3 π mm-rad horizontally and 0.6–1.0 π mm-rad vertically, a horizontal dispersion of 90–190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE