Policy Considerations for States Supporting Stem Cell Research: Evidence from a Survey of Stem Cell Scientists

This is a preprint of an Article accepted for publication in Public Administration Review © the American Society for Public Administration. The definitive version is available at http://www.blackwell-synergy.com.Five states now provide funding for stem cell research and numerous states are developing or debating stem cell research policies. Yet despite this interest, few data exist to help policymakers design policies or forecast their impact. This article reports novel data from two surveys: one directed at those most affected by these policies - stem cell scientists themselves - and one at a group of biomedical researchers from less contentious fields. These data identified relatively high mobility among stem cell scientists, particularly those in states with restrictive policies, and a strong preference for states with permissive policies. These findings suggest state-specific policies may prove to be effective recruiting tools. They also suggest specific recruitment strategies and highlight the importance of first-mover advantage as several states compete to recruit from the same limited pool of mobile scientists. This research aims to provide a factual basis to support ongoing policy formulation in the area.This research was funded primarily by a grant from the Policy Research Institute for the Region at Princeton Universit

Enhancement of the ν=5/2\nu = 5/2 Fractional Quantum Hall State in a Small In-Plane Magnetic Field

Using a 50-nm width, ultra-clean GaAs/AlGaAs quantum well, we have studied the Landau level filling factor $\nu = 5/2$ fractional quantum Hall effect in a perpendicular magnetic field $B \sim$ 1.7 T and determined its dependence on tilted magnetic fields. Contrary to all previous results, the 5/2 resistance minimum and the Hall plateau are found to strengthen continuously under an increasing tilt angle $0 < \theta < 25^\circ$ (corresponding to an in-plane magnetic field 0 $<$ $B_\parallel$ $< 0.8$ T). In the same range of $\theta$ the activation gaps of both the 7/3 and the 8/3 states are found to increase with tilt. The 5/2 state transforms into a compressible Fermi liquid upon tilt angle $\theta > 60^\circ$, and the composite fermion series [2+$p/(2p\pm1)$], $p =$ 1, 2 can be identified. Based on our results, we discuss the relevance of a Skyrmion spin texture at $\nu = 5/2$ associated with small Zeeman energy in wide quantum wells, as proposed by W$\acute{\text o}$js $et$ $al$., Phys. Rev. Lett. 104, 086801 (2010).Comment: 5+ pages, 3 figures, accepted for by Phy. Rev. Let

New X-ray Clusters in the EMSS II: Optical Properties

We present optical images for 9 new clusters of galaxies we have found in a reanalysis of the Einstein IPC images comprising the Extended Medium Sensitivity Survey (EMSS). Based on the presence of a red sequence of galaxies in a color-magnitude (CM) diagram, a redshift is estimated for each cluster. Galaxy overdensities (cluster richnesses) are measured in each field using the B_gc statistic which allows their plausible identification with the X-ray emission. The nature of our X-ray detection algorithm suggests that most of these clusters have low X-ray surface brightness (LSB) compared to the previously known EMSS clusters. We compare the optical and X-ray observations of these clusters with the well-studied Canadian Network for Observational Cosmology (CNOC) subsample of the EMSS, and conclude that the new clusters exhibit a similar range of optical richnesses, X-ray luminosities, and, somewhat surprisingly, galaxy populations as the predominantly rich, relaxed EMSS/CNOC clusters.Comment: Accepted to ApJ, 17 pages, 14 figures, uses emulateapj5.st

PROPERTIES OF THE 24 DAY MODULATION IN GX 13+1 FROM NEAR-INFRARED AND X-RAY OBSERVATIONS

A 24 day period for the low-mass X-ray binary (LMXB) GX 13+1 was previously proposed on the basis of seven years of RXTE All-Sky Monitor (ASM) observations and it was suggested that this was the orbital period of the system. This would make it one of the longest known orbital periods for a Galactic LMXB powered by Roche lobe overflow. We present here the results of (1) K-band photometry obtained with the SMARTS Consortium CTIO 1.3 m telescope on 68 nights over a 10 month interval; (2) continued monitoring with the RXTE ASM, analyzed using a semi-weighted power spectrum instead of the data filtering technique previously used; and (3) Swift Burst Alert Telescope (BAT) hard X-ray observations. Modulation near 24 days is seen in both the K band and additional statistically independent ASM X-ray observations. However, the modulation in the ASM is not strictly periodic. The periodicity is also not detected in the Swift BAT observations, but modulation at the same relative level as seen with the ASM cannot be ruled out. If the 24 day period is the orbital period of system, this implies that the X-ray modulation is caused by structure that is not fixed in location. A possible mechanism for the X-ray modulation is the dipping behavior recently reported from XMM-Newton observations

Phosphotyrosine Signaling Analysis in Human Tumors Is Confounded by Systemic Ischemia-Driven Artifacts and Intra-Specimen Heterogeneity

Tumor protein phosphorylation analysis may provide insight into intracellular signaling networks underlying tumor behavior, revealing diagnostic, prognostic or therapeutic information. Human tumors collected by The Cancer Genome Atlas program potentially offer the opportunity to characterize activated networks driving tumor progression, in parallel with the genetic and transcriptional landscape already documented for these tumors. However, a critical question is whether cellular signaling networks can be reliably analyzed in surgical specimens, where freezing delays and spatial sampling disparities may potentially obscure physiologic signaling. To quantify the extent of these effects, we analyzed the stability of phosphotyrosine (pTyr) sites in ovarian and colon tumors collected under conditions of controlled ischemia and in the context of defined intratumoral sampling. Cold-ischemia produced a rapid, unpredictable, and widespread impact on tumor pTyr networks within 5 minutes of resection, altering up to 50% of pTyr sites by more than 2-fold. Effects on adhesion and migration, inflammatory response, proliferation, and stress response pathways were recapitulated in both ovarian and colon tumors. In addition, sampling of spatially distinct colon tumor biopsies revealed pTyr differences as dramatic as those associated with ischemic times, despite uniform protein expression profiles. Moreover, intratumoral spatial heterogeneity and pTyr dynamic response to ischemia varied dramatically between tumors collected from different patients. Overall, these findings reveal unforeseen phosphorylation complexity, thereby increasing the difficulty of extracting physiologically relevant pTyr signaling networks from archived tissue specimens. In light of this data, prospective tumor pTyr analysis will require appropriate sampling and collection protocols to preserve in vivo signaling features.National Institutes of Health (U.S.) (Grant U24 CA159988

Predictors of rapid aortic root dilation and referral for aortic surgery in Marfan syndrome

Few data exist regarding predictors of rapid aortic root dilation and referral for aortic surgery in Marfan syndrome (MFS). To identify independent predictors of the rate of aortic root (AoR) dilation and referral for aortic surgery, we investigated the data from the Pediatric Heart Network randomized trial of atenolol versus losartan in young patients with MFS. Data were analyzed from the echocardiograms at 0, 12, 24, and 36months read in the core laboratory of 608 trial subjects, aged 6months to 25 years, who met original Ghent criteria and had an AoR z-score (AoRz)>3. Repeated measures linear and logistic regressions were used to determine multivariable predictors of AoR dilation. Receiver operator characteristic curves were used to determine cut-points in AoR dilation predicting referral for aortic surgery. Multivariable analysis showed rapid AoR dilation as defined by change in AoRz/year>90th percentile was associated with older age, higher sinotubular junction z-score, and atenolol use (R-2=0.01) or by change in AoR diameter (AoRd)/year>90th percentile with higher sinotubular junction z-score and non-white race (R-2=0.02). Referral for aortic root surgery was associated with higher AoRd, higher ascending aorta z-score, and higher sinotubular junction diameter:ascending aorta diameter ratio (R-2=0.17). Change in AoRz of 0.72 SD units/year had 42% sensitivity and 92% specificity and change in AoRd of 0.34cm/year had 38% sensitivity and 95% specificity for predicting referral for aortic surgery. In this cohort of young patients with MFS, no new robust predictors of rapid AoR dilation or referral for aortic root surgery were identified. Further investigation may determine whether generalized proximal aortic dilation and effacement of the sinotubular junction will allow for better risk stratification. Rate of AoR dilation cut-points had high specificity, but low sensitivity for predicting referral for aortic surgery, limiting their clinical use. Clinical Trial Number ClinicalTrials.gov number, NCT00429364