Fermi Discovery of Gamma-Ray Emission from NGC 1275

We report the discovery of high-energy (E>100 MeV) gamma-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma ray Space Telescope. The positional center of the gamma-ray source is only ~3' away from the NGC 1275 nucleus, well within the 95% LAT error circle of ~5'.The spatial distribution of gamma-ray photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F_gamma = (2.10+-0.23)x 10^{-7} ph (>100 MeV) cm^{-2} s^{-1} and Gamma = 2.17+-0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period.Previous EGRET observations gave an upper limit of F_gamma 100 MeV) cm^{-2} s^{-1} to the gamma-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.Comment: 27 pages, 7 figures, Accepted for publication in the Astrophysical Journa

A Theoretical Trade-Off Between Wave Drag and Sonic Boom Loudness Due to Equivalent Area Changes on a Supersonic Body

The NASA University Leadership Initiative (ULI) titled ”Adaptive Aerostructures for Revolutionary Civil Supersonic Transportation” consists of a team of university and industry partners studying the feasibility of reducing the perceived loudness of the sonic boom by introducing an adaptive geometry at localized regions of an aircraft’s outer-mold line. The Utah State University AeroLab is a member of this ULI team and has produced low-fidelity tools to predict the aerodynamic and boom loudness effects from localized changes to the geometry. Such changes to the geometry affect both the sonic boom loudness and wave drag; however, the precise relationship between boom loudness and wave drag is not well understood for a morphing supersonic geometry. The current work utilizes an equivalent area approach and expresses this equivalent area using a Fourier sine series. An optimization routine was used to search for the Fourier coefficients that produce a minimum perceived level of decibels of the sonic boom for an optimized equivalent area distribution. The results for each candidate are compared against the Sears-Haack’s equivalent area, ground pressure signature, perceived noise, and wave drag. These tools were used to obtain a Pareto front of solutions to better understand the theoretical trade-off between wave drag and perceived noise on the ground as equivalent area changes on a supersonic geometry

Serum cytokine levels as predictive biomarkers of benefit from ipilimumab in small cell lung cancer

Background. Immunotherapy has shown efficacy in small cell lung cancer (SCLC), but only a subset of patients benefits. Surrogate biomarkers are urgently needed. Our aim was to evaluate serum Th1, Th2, and proinflammatory cytokines in two cohorts of SCLC patients before and during treatment with chemotherapy with or without ipilimumab and to correlate them with survival. Patients and methods. Two cohorts of SCLC patients were studied: patients treated with chemotherapy (n = 47), and patients treated with chemotherapy plus ipilimumab (n = 37). Baseline, on-treatment and after-treatment serum samples were evaluated for the presence of IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IFN-gamma, TNF-alpha, GM-CSF, and Mip-1alpha using a Luminex assay. Differential changes in cytokines between cohorts were analyzed. Associations between cytokine levels and their changes with overall survival were evaluated. Results. Patients treated with ipilimumab showed a global increase of all cytokines after treatment initiation. A high level of IL-8 at baseline was associated with worse prognosis regardless of treatment. Baseline increased IL-2 levels predicted sensitivity to ipilimumab, while high IL-6 and TNF-alpha predicted resistance. An on-treatment increase in IL-4 levels in patients treated with immune-chemotherapy was associated with a better overall survival. Conclusions. The addition of ipilimumab to standard chemotherapy in SCLC modulates the serum levels of cytokines. Baseline levels and their change over time relate to overall survival. Blood-based biomarkers are convenient for patients, and our results support prospective validation of cytokines as predictive biomarkers for ipilimumab in SCLC

Exploring the Future of Indian Health Information Systems

The Data Policy Roundtable - The Future of Indian Health Information Systems was convened to explore options and develop strategies for future Indian Health Service/Tribal/Urban (I/T/U) program information systems. The concerns and needs of both tribes who chose to contract/compact and those who did not were considered.The focus was on developing strategies to create a new Indian health information system, one that was not an Indian Health Service system but rather a system designed and supported by tribal and urban health care delivery organizations and the Indian Health Service.The participants represented a broad range of concerns and needs. They identified problems, issues, and solutions. Participants generously shared information and reports about the often extensive work their groups have done to assess their needs and study the options available to them to improve their systems to meet their needs.The group benefited from the candid expression of viewpoints coming from representatives of the tribes and urban groups, members of national and regional tribal health boards, medical professionals, and staff from various Indian Health Service divisions, industry experts, and interested observers. As the roundtable discussion of issues, concerns, and options progressed it became clear that in the future an Indian Health Information System would be driven increasingly by the needs of and ultimately directed by the tribes (both those who chose to contract/compact and those who did not) and urban Indian organizations. This report summarizes ten recommendations resulting from the roundtable

Refining pathological evaluation of neoadjuvant therapy for adenocarcinoma of the esophagus

AIM: To assess tumour regression grade (TRG) and lymph node downstaging to help define patients who benefit from neoadjuvant chemotherapy.METHODS: Two hundred and eighteen consecutive patients with adenocarcinoma of the esophagus or gastro-esophageal junction treated with surgery alone or neoadjuvant chemotherapy and surgery between 2005 and 2011 at a single institution were reviewed. Triplet neoadjuvant chemotherapy consisting of platinum, fluoropyrimidine and anthracycline was considered for operable patients (World Health Organization performance status ? 2) with clinical stage T2-4 N0-1. Response to neoadjuvant chemotherapy (NAC) was assessed using TRG, as described by Mandard et al. In addition lymph node downstaging was also assessed. Lymph node downstaging was defined by cN1 at diagnosis: assessed radiologically (computed tomography, positron emission tomography, endoscopic ultrasonography), then pathologically recorded as N0 after surgery; ypN0 if NAC given prior to surgery, or pN0 if surgery alone. Patients were followed up for 5 years post surgery. Recurrence was defined radiologically, with or without pathological confirmation. An association was examined between t TRG and lymph node downstaging with disease free survival (DFS) and a comprehensive range of clinicopathological characteristics.RESULTS: Two hundred and eighteen patients underwent esophageal resection during the study interval with a mean follow up of 3 years (median follow up: 2.552, 95%CI: 2.022-3.081). There was a 1.8% (n = 4) inpatient mortality rate. One hundred and thirty-six (62.4%) patients received NAC, with 74.3% (n = 101) of patients demonstrating some signs of pathological tumour regression (TRG 1-4) and 5.9% (n = 8) having a complete pathological response. Forty four point one percent (n = 60) had downstaging of their nodal disease (cN1 to ypN0), compared to only 15.9% (n = 13) that underwent surgery alone (pre-operatively overstaged: cN1 to pN0), (P < 0.0001). Response to NAC was associated with significantly increased DFS (mean DFS; TRG 1-2: 5.1 years, 95%CI: 4.6-5.6 vs TRG 3-5: 2.8 years, 95%CI: 2.2-3.3, P < 0.0001). Nodal down-staging conferred a significant DFS advantage for those patients with a poor primary tumour response to NAC (median DFS; TRG 3-5 and nodal down-staging: 5.533 years, 95%CI: 3.558-7.531 vs TRG 3-5 and no nodal down-staging: 1.114 years, 95%CI: 0.961-1.267, P < 0.0001).CONCLUSION: Response to NAC in the primary tumour and in the lymph nodes are both independently associated with improved DFS

YPAR, Critical Whiteness, and Generative Possibilities. A Response to “Sam and Cristina: A Dialogue Between a High School Teacher and Student about the Commoditization of People of Color”

In this response to the article by Tanner and Corrie, the authors provide three critiques of the methodology and theoretical framing of the study with the hopes of informing future scholarship and practice. Specifically, the three critiques addressed in this paper include the integration of CWS frameworks and YPAR methodology, the application and description of CWS and YPAR frameworks, and the role of power in the relationship between educator and student that served as the central medium for the study

Synthetic stellar populations: single stellar populations, stellar interior models and primordial proto-galaxies

We present a new set of stellar interior and synthesis models for predicting the integrated emission from stellar populations in star clusters and galaxies of arbitrary age and metallicity. This work differs from existing spectral synthesis codes in a number of important ways, namely (1) the incorporation of new stellar evolutionary tracks, with sufficient resolution in mass to sample rapid stages of stellar evolution; (2) a physically consistent treatment of evolution in the HR diagram, including the approach to the main sequence and the effects of mass loss on the giant and horizontal-branch phases. Unlike several existing models, ours yield consistent ages when used to date a coeval stellar population from a wide range of spectral features and colour indexes. We rigorously discuss degeneracies in the age-metallicity plane and show that inclusion of spectral features blueward of 4500 AA, suffices to break any remaining degeneracy and that with moderate S/N spectra (10 per 20AA, resolution element) age and metallicity are not degenerate. We also study sources of systematic errors in deriving the age of a single stellar population and conclude that they are not larger than 10-15%. We illustrate the use of single stellar populations by predicting the colors of primordial proto-galaxies and show that one can first find them and then deduce the form of the IMF for the early generation of stars in the universe. Finally, we provide accurate analytic fitting formulas for ultra fast computation of colors of single stellar populations. The models can be found at http://www.physics.upenn.edu/~rauljComment: MNRAS in pres

Are Q-stars a serious threat for stellar-mass black hole candidates?

We examine the status of the threat posed to stellar-mass black hole candidates by the possible existence of Q-stars (compact objects with an exotic equation of state which might have masses well above the normally-accepted maximum for standard neutron stars). We point out that Q-stars could be extremely compact (with radii less than 1.5 times the corresponding Schwarzschild radius) making it quite difficult to determine observationally that a given object is a black hole rather than a Q-star, unless there is direct evidence for the absence of a solid surface. On the other hand, in order for a Q-star to have a mass as high as that inferred for the widely-favoured black hole candidate V404 Cygni, it would be necessary for the Q-matter equation of state to apply already at densities an order of magnitude below that of nuclear matter and this might well be considered implausible on physical grounds. We also describe how rotation affects the situation and discuss the prospects for determining observationally that black hole candidates are not Q-stars.Comment: 4 pages Latex, 5 figures, to appear in MNRA

Asteroid Systems: Binaries, Triples, and Pairs

In the past decade, the number of known binary near-Earth asteroids has more than quadrupled and the number of known large main belt asteroids with satellites has doubled. Half a dozen triple asteroids have been discovered, and the previously unrecognized populations of asteroid pairs and small main belt binaries have been identified. The current observational evidence confirms that small (<20 km) binaries form by rotational fission and establishes that the YORP effect powers the spin-up process. A unifying paradigm based on rotational fission and post-fission dynamics can explain the formation of small binaries, triples, and pairs. Large (>20 km) binaries with small satellites are most likely created during large collisions.Comment: 31 pages, 12 figures. Chapter in the book ASTEROIDS IV (in press