Hasil untuk "astro-ph.HE"

S. Juneau, K. Olsen, R. Nikutta et al.

The advent of increasingly large and complex datasets has fundamentally altered the way that scientists conduct astronomy research. The need to work closely to the data has motivated the creation of online science platforms, which include a suite of software tools and services, therefore going beyond data storage and data access. We present two example applications of Jupyter as a part of astrophysical science platforms for professional researchers and students. First, the Astro Data Lab is developed and operated by NOIRLab with a mission to serve the astronomy community with now over 1500 registered users. Second, the Dark Energy Spectroscopic Instrument science platform serves its geographically distributed team comprising about 900 collaborators from over 90 institutions. We describe the main uses of Jupyter and the interfaces that needed to be created to embed it within science platform ecosystems. We use these examples to illustrate the broader concept of empowering researchers and providing them with access to not only large datasets but also cutting-edge software, tools, and data services without requiring any local installation, which can be relevant for a wide range of disciplines. Future advances may involve science platform networks, and tools for simultaneously developing Jupyter notebooks to facilitate collaborations.

C. Fung, N. Vapiwala, M. Mattes et al.

Purpose To assess US radiation oncologists’ views on practice scope and the ideal role of the radiation oncologist (RO), the American Society for Radiation Oncology (ASTRO) conducted a scope of practice survey. Methods and Materials In spring 2019, ASTRO distributed an online survey to 3822 US RO members. The survey generated 984 complete responses (26% response rate) for analysis. Face validity testing confirmed respondents were representative of ASTRO’s RO membership. Results Nearly all respondents agreed that “ROs should be leaders in oncologic care.” Respondents indicated the ideal approach to patient care was to provide “an independent opinion on radiation therapy and other treatment options” (82.5%) or “an independent opinion on radiation therapy but not outside of it” (16.1%), with only 1.4% favoring provision of “radiation therapy at the request of the referring physician” as the ideal approach. Actual practice fully matched the ideal approach in 18.2% of respondents. For the remaining majority, actual practice did not always match the ideal and comprised a mix of approaches that included providing radiation at the referring physician’s request 24.0% of the time on average. Reasons for the mismatch included fear of alienating referring physicians and concern for offering an unwelcome opinion. One-fifth of respondents expressed a desire to expand the scope of service though interspecialty politics and insufficient training were potential barriers. Respondents interested in expanding scope of practice were on average earlier in their career (average years in practice 13.3) than those who were not interested (average years in practice 17.2, P < .001). Radiopharmaceuticals administration, medical marijuana and anticancer medications prescribing, and RO inpatient service represented areas of interest for expansion but also knowledge gaps. Conclusions These results provide insight regarding US ROs’ scope of practice and attitudes on the ideal role of the RO. For most ROs, to provide an independent opinion on treatment options represented the ideal approach to care, but barriers such as concern of alienating referring physicians prevented many from fully adhering to their ideal in practice. Actual practice commonly comprised a mixed approach, including the least favored scenario of delivering radiation at the referring physician’s request one-quarter of the time, highlighting the influence of interspecialty politics on practice behavior. Advocacy for open communication and meaningful interdisciplinary collaboration presents an actionable solution toward a more balanced relationship with other specialties as ROs strive to better fulfill the vision of being leaders in oncologic care and being our best for our patients. The study also identified interest in expanding into nontraditional domains that offer opportunities to address unmet needs in the cancer patient’s journey and elevate radiation oncology within the increasingly value-based US health care system.

K. Asad, J. Girard, M. D. Villers et al.

After a decade of design and construction, South Africa's SKA-MID precursor MeerKAT has begun its science operations. To make full use of the widefield capability of the array, it is imperative that we have an accurate model of the primary beam of its antennas. We have used an available L-band full-polarization astro-holographic observation and electromagnetic simulation to create sparse representations of the beam using principal components and Zernike polynomials. The spectral behaviour of the spatial coefficients has been modelled using discrete cosine transform. We have provided the Zernike-based model over a diameter of 10 degrees in an associated software tool that can be useful for direction dependent calibration and imaging. The model is more accurate for the diagonal elements of the beam Jones matrix and at lower frequencies. As we get more accurate beam measurements and simulations in the future, especially for the cross-polarization patterns, our pipeline can be used to create more accurate sparse representations of MeerKAT beam.

R. Essig, J. Jaros, W. Wester et al.

Dark sectors, consisting of new, light, weakly-coupled particles that do not interact with the known strong, weak, or electromagnetic forces, are a particularly compelling possibility for new physics. Nature may contain numerous dark sectors, each with their own beautiful structure, distinct particles, and forces. This review summarizes the physics motivation for dark sectors and the exciting opportunities for experimental exploration. It is the summary of the Intensity Frontier subgroup "New, Light, Weakly-coupled Particles" of the Community Summer Study 2013 (Snowmass). We discuss axions, which solve the strong CP problem and are an excellent dark matter candidate, and their generalization to axion-like particles. We also review dark photons and other dark-sector particles, including sub-GeV dark matter, which are theoretically natural, provide for dark matter candidates or new dark matter interactions, and could resolve outstanding puzzles in particle and astro-particle physics. In many cases, the exploration of dark sectors can proceed with existing facilities and comparatively modest experiments. A rich, diverse, and low-cost experimental program has been identified that has the potential for one or more game-changing discoveries. These physics opportunities should be vigorously pursued in the US and elsewhere.

Saif S. Ahmad, M. Crittenden, P. Tran et al.

Radiotherapy is a fundamental component of treatment for the majority of patients with cancer. In recent decades, technological advances have enabled patients to receive more targeted doses of radiation to the tumor, with sparing of adjacent normal tissues. There had been hope that the era of precision medicine would enhance the combination of radiotherapy with targeted anticancer drugs; however, this ambition remains to be realized. In view of this lack of progress, the FDA–AACR–ASTRO Clinical Development of Drug–Radiotherapy Combinations Workshop was held in February 2018 to bring together stakeholders and opinion leaders from academia, clinical radiation oncology, industry, patient advocacy groups, and the FDA to discuss challenges to introducing new drug–radiotherapy combinations to the clinic. This Perspectives in Regulatory Science and Policy article summarizes the themes and action points that were discussed. Intelligent trial design is required to increase the number of studies that efficiently meet their primary outcomes; endpoints to be considered include local control, organ preservation, and patient-reported outcomes. Novel approaches including immune-oncology or DNA-repair inhibitor agents combined with radiotherapy should be prioritized. In this article, we focus on how the regulatory challenges associated with defining a new drug–radiotherapy combination can be overcome to improve clinical outcomes for patients with cancer.

P. Gilbo, L. Potters, Lucille N Lee

Purpose Hypofractionation (HF) of whole breast irradiation has become a standard treatment regimen because randomized trials continue to demonstrate equivalence in survival and local control compared with conventional fractionation. In 2011, the American Society for Radiation Oncology (ASTRO) adopted clinical guidelines on the proper selection of HF. Nevertheless, utilization remains lower than predicted. We evaluate the effects of clinical directives that serve as default treatment decisions and prospective contouring rounds on the implementation of HF in a large, multicenter radiation oncology department. Methods and materials In 2010, we implemented consensus-driven and evidence-based clinical directives to guide treatment decisions. Five directives were available for adjuvant breast cancer treatment, including conventional fractionation and HF approaches, and were selected on the basis of disease specifics and clinical judgment. In 2012, we instituted prospective contouring rounds wherein the treating physicians presented their directive selection and patient contours for peer-review and consensus opinion. For this study, charts for patients with early stage breast cancer were reviewed. A total of 1043 cases of breast cancer were identified. Patients receiving HF were analyzed on the basis of the ASTRO 2011 guidelines and adherence to our more inclusive clinical directives. Results For the ASTRO-endorsed group (n = 685), 49% of patients received HF in 2011, and 80% received HF in 2015. For the directives-endorsed group (n = 1042), 47% of patients received HF in 2011, and 73% received HF in 2015. Conclusions HF is underutilized despite equivalent local control, superior toxicity profile, and noninferior late effects. Our study demonstrates the possibility of achieving high levels of utilization in a large, multisite, outpatient setting. Factors responsible may include default rules established through the development of consensus-based treatment directives, peer review by faculty, and strong financial leadership to implement HF when indicated. To our knowledge, this is the first example of combining both consensus-based treatment directives and prospective contouring rounds in an attempt to change practice patterns.

H. Quon, N. Vapiwala, A. Forastiere et al.

C. Hahn, B. Kavanagh, A. Bhatnagar et al.

C. Kilbourne, J. Adams, R. Brekosky et al.

I. Chetty, M. Martel, D. Jaffray et al.

C. Mayo, J. Deasy, B. Chera et al.

D. Phillips, A. Glenday, Chih-Hao Li et al.

We deployed two wavelength calibrators based on laser frequency combs ("astro-combs") at an astronomical telescope. One astro-comb operated over a 100 nm band in the deep red (∼ 800 nm) and a second operated over a 20 nm band in the blue (∼ 400 nm). We used these red and blue astro-combs to calibrate a high-resolution astrophysical spectrograph integrated with a 1.5 m telescope, and demonstrated calibration precision and stability sufficient to enable detection of changes in stellar radial velocity < 1 m/s.

F Camilo, D. Lorimer, P. Freire et al.

L. Potters, C. Morgenstern, E. Calugaru et al.

L. Potters, C. Morgenstern, E. Calugaru et al.

A. Rudolph, E. Prather, G. Brissenden et al.

Joseph L. Chin, C. Ng, N. Touma et al.

R. Windhorst, V. Taylor, R. Jansen et al.

C. Honeycutt, W. Clapham, S. S. Leach