S. Lutz, L. Berk, E. Chang et al.
Hasil untuk "astro-ph.GA"
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J. Eastham, G. Auffenberg, D. Barocas et al.
Purpose: The summary presented herein represents Part II of the three-part series dedicated to Clinically Localized Prostate Cancer: AUA/ASTRO Guideline, discussing principles of active surveillance and surgery as well as follow-up for patients after primary treatment. Please refer to Parts I and III for discussion of risk assessment, staging, and risk-based management (Part I), and principles of radiation and future directions (Part III). Materials and Methods: The systematic review utilized to inform this guideline was conducted by an independent methodological consultant. A research librarian conducted searches in Ovid MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. The methodology team supplemented searches of electronic databases with the studies included in the prior AUA review and by reviewing reference lists of relevant articles. Results: The Clinically Localized Prostate Cancer Panel created evidence- and consensus-based guideline statements to aid clinicians in the management of patients with clinically localized prostate cancer. Statements regarding active surveillance, surgical management, and patient follow-up are detailed. Conclusion: This guideline aims to inform clinicians treating patients with clinically localized prostate cancer. Continued research and publication of high-quality evidence from future trials will be essential to further improve care for these men.
S. Apisarnthanarax, A. Barry, M. Cao et al.
M. Libralato, A. Bellini, D. Massari et al.
The Hubble Missing Globular Cluster Survey (MGCS) has taken one of the last opportunities to complete the census of Galactic globular clusters (GCs) started by past Hubble Space Telescope (HST) programs, securing high-resolution data for 34 GCs never observed before by HST. The previous papers of the series have highlighted the astrometric and photometric potential of the project by analyzing a subsample of targets. We present, and release to the community, the official astro-photometric catalogs of the MGCS for all GCs imaged by this project. We describe the data reduction using state-of-the-art techniques designed for HST. We discuss the photometric calibration and show, for the first time, the synergy with the Gaia catalog to ensure homogeneous photometry across our data set. We compute artificial-star tests that can be used to assess systematics and the completeness level of our data. We combined HST and Gaia data to refine the absolute PMs of our GCs, reaching a precision $\sim$3 times better than that of Gaia alone. We used these new PMs to update (and to determine for the first time for six systems) the associations between GCs and their putative galaxy progenitors. This work continues decades-long efforts of large Treasury programs in sharing precise and accurate atlases to the community for studying GCs across a wide range of scientific endeavors.
Sara Alcorn, Á. Cortés, Lisa Bradfield et al.
PURPOSE This guideline provides evidence-based recommendations for palliative external beam radiation therapy (RT) in symptomatic bone metastases. METHODS The American Society for Radiation Oncology (ASTRO) convened a task force to address 5 key questions regarding palliative RT in symptomatic bone metastases. Based on a systemic review by the Agency for Health Research and Quality, recommendations using predefined consensus-building methodology were established; evidence quality and recommendation strength were also assessed. RESULTS For palliative RT for symptomatic bone metastases, RT is recommended for managing pain from bone metastases and spine metastases with or without spinal cord or cauda equina compression. Regarding other modalities with RT, for patients with spine metastases causing spinal cord or cauda equina compression, surgery and postoperative RT are conditionally recommended over RT alone. Furthermore, dexamethasone is recommended for spine metastases with spinal cord or cauda equina compression. Patients with non-spine bone metastases requiring surgery are recommended postoperative RT. Symptomatic bone metastases treated with conventional RT are recommended 800 cGy in 1 fraction (800 cGy/1fx), 2000 cGy/5fx, 2400 cGy/6fx, or 3000 cGy/10fx. Spinal cord or cauda equina compression in patients ineligible for surgery and receiving conventional RT are recommended 800 cGy/1fx, 1600 cGy/2fx, 2000 cGy/5fx, or 3000 cGy/10fx. Symptomatic bone metastases in selected patients with good performance status without surgery or neurological symptoms/signs are conditionally recommended SBRT over conventional palliative RT. Spine bone metastases re-irradiated with conventional RT are recommended 800 cGy/1fx, 2000 cGy/5fx, 2400 cGy/6fx, or 2000 cGy/8fx; non-spine bone metastases re-irradiated with conventional RT are recommended 800 cGy/1fx, 2000 cGy/5fx, or 2400 cGy/6fx. Determination of an optimal RT approach/regimen requires whole person assessment, including prognosis, previous RT dose if applicable, risks to normal tissues, quality of life, cost implications, and patient goals and values. Relatedly, for patient-centered optimization of treatment-related toxicities and quality of life, shared decision-making is recommended. CONCLUSIONS Based on published data, the ASTRO task force's recommendations inform best clinical practices on palliative RT for symptomatic bone metastases.
Todd M. Morgan, S. Boorjian, M. Buyyounouski et al.
Purpose: The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part I of a three-part series focusing on treatment decision-making at the time of suspected biochemical recurrence (BCR) after radical prostatectomy (RP). Please refer to Part II for discussion of treatment delivery for non-metastatic BCR after RP and Part III for discussion of evaluation and management of recurrence after radiotherapy (RT) and focal therapy, regional recurrence, and oligometastasis. Materials and Methods: The systematic review that informs this Guideline was based on searches in Ovid MEDLINE (1946 to July 21, 2022), Cochrane Central Register of Controlled Trials (through August 2022), and Cochrane Database of Systematic Reviews (through August 2022). Update searches were conducted on July 26, 2023. Searches were supplemented by reviewing electronic database reference lists of relevant articles. Results: In a collaborative effort between AUA, ASTRO, and SUO, the Salvage Therapy for Prostate Cancer Panel developed evidence- and consensus-based statements to provide guidance for the care of patients who experience BCR after initial definitive local therapy for clinically localized disease. Conclusions: Advancing work in the area of diagnostic tools (particularly imaging), biomarkers, radiation delivery, and biological manipulation with the evolving armamentarium of therapeutic agents will undoubtedly present new opportunities for patients to experience long-term control of their cancer while minimizing toxicity.
D. Margalit, C. Anker, M. Aristophanous et al.
PURPOSE Human Papilloma Virus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) is a distinct disease from other head and neck tumors. This guideline provides evidence-based recommendations on the critical decisions in its curative treatment, including both definitive and postoperative radiation therapy (RT) management. METHODS ASTRO convened a task force to address 5 key questions on the use of RT for management of HPV-associated OPSCC. These questions included indications for definitive and postoperative RT and chemoradiation; dose-fractionation regimens and treatment volumes; preferred RT techniques and normal tissue considerations; and posttreatment management decisions. The task force did not address indications for primary surgery versus RT. Recommendations were based on a systematic literature review and created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength. RESULTS Concurrent cisplatin is recommended for patients receiving definitive RT with T3-4 disease and/or 1 node >3 cm, or multiple nodes. For similar patients who are ineligible for cisplatin, concurrent cetuximab, carboplatin/5-fluorouracil, or taxane-based systemic therapy are conditionally recommended. In the postoperative setting, RT with concurrent cisplatin (either schedule) is recommended for positive surgical margins or extranodal extension. Postoperative RT alone is recommended for pT3-4 disease, >2 nodes, or a single node >3 cm. Observation is conditionally recommended for pT1-2 disease and a single node ≤3 cm without other risk factors. For patients treated with definitive RT with concurrent systemic therapy, 7000 cGy in 33 to 35 fractions is recommended, and for patients receiving postoperative RT without positive surgical margins and extranodal extension, 5600 to 6000 cGy is recommended. For all patients receiving RT, intensity modulated RT over 3-dimensional techniques with reduction in dose to critical organs at risk (including salivary and swallowing structures) is recommended. Reassessment with positron emission tomography-computed tomography is recommended approximately 3 months after definitive RT/chemoradiation, and neck dissection is recommended for convincing evidence of residual disease; for equivocal positron emission tomography-computed tomography findings, either neck dissection or repeat imaging is recommended. CONCLUSIONS The role and practice of RT continues to evolve for HPV-associated OPSCC, and these guidelines inform best clinical practice based on the available evidence.
Robert D. Mathieu, Onno R. Pols
The scope of this literature review is observations of the products of first-stage evolution for binaries having components with M < 2 $M_\odot$. A taxonomy for these products comprises dwarfs ("blue stragglers"), giants ("yellow stragglers"), subdwarf B stars, and giant-like stars ("sub-subgiants" and "red stragglers"). This literature review is organized according to this taxonomy within three distinct environments: open star clusters, globular star clusters, and the Galactic field. This literature review is the Supplemental Material for Blue Stragglers and Friends: Initial Evolutionary Pathways in Close Low-Mass Binaries (Mathieu & Pols, 2025, ARAA, 63:467-512, doi: www.annualreviews.org/content/journals/10.1146/annurev-astro-071221-054402). It is intended to support and expand on Section 3 of the main text of this Annual Review of Astronomy and Astrophysics, where an integrated perspective on the common and contrasting astrophysical properties of these binary evolution products is provided. Figures used in the main text to highlight key observational results are referenced in this literature review. The closing date of this review is January 17, 2025, with some citations subsequently updated.
Hayley Roberts, Jeremy Darling, Kelley M. Hess et al.
OH megamasers (OHMs) are extragalactic masers found primarily in gas-rich galaxy major mergers. To date, only $\sim$120 OHMs have been cataloged since their discovery in 1982, and efforts to identify distinct characteristics of OHM host galaxies have remained inconclusive. As radio astronomy advances with next-generation telescopes and extensive 21 cm HI surveys, precursors to the Square Kilometre Array (SKA) are expected to detect the 18 cm OH masing line with significantly increased frequency, potentially expanding the known OHM population tenfold. These detections, however, risk confusion with lower-redshift HI emitters unless accompanied by independent spectroscopic redshifts. Building on methods proposed by Roberts et al. (arXiv:2102.12486) for distinguishing these interloping OHMs via near- to mid-IR photometry and emission line frequencies, we apply these techniques to data from the Arecibo Legacy Fast ALFA [Arecibo L-band Feed Array] (ALFALFA) survey and a preliminary APERture Tile In Focus (Apertif) HI emission line catalog from the Westerbork Synthesis Radio Telescope. Our study, utilizing the Apache Point Observatory 3.5m telescope to obtain optical spectroscopic redshifts of 142 candidates (107 from ALFALFA and 35 from Apertif), confirms five new OHM host galaxies and reidentifies two previously catalogued OHMs misclassified as HI emitters in ALFALFA. These findings support the predictions from Roberts et al. (arXiv:2102.12486 [astro-ph.GA]) and underscore the evolving landscape of radio astronomy in the context of next-generation telescopes.
Febi Talitha Salsabila, Machful Indrakurniawan
Todd M. Morgan, S. Boorjian, M. Buyyounouski et al.
Purpose: The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part III of a three-part series focusing on evaluation and management of suspected non-metastatic recurrence after radiotherapy (RT) and focal therapy, evaluation and management of regional recurrence, management for molecular imaging metastatic recurrence, and future directions. Please refer to Part I for discussion of treatment decision-making and Part II for discussion of treatment delivery for non-metastatic biochemical recurrence (BCR) after radical prostatectomy (RP). Materials and Methods: The systematic review that informs this Guideline was based on searches in Ovid MEDLINE (1946 to July 21, 2022), Cochrane Central Register of Controlled Trials (through August 2022), and Cochrane Database of Systematic Reviews (through August 2022). Update searches were conducted on July 26, 2023. Searches were supplemented by reviewing electronic database reference lists of relevant articles. Results: In a collaborative effort between AUA, ASTRO, and SUO, the Salvage Therapy for Prostate Cancer Guideline Panel developed evidence- and consensus-based guideline statements to provide guidance for the care of patients who experience BCR after initial definitive local therapy for clinically localized disease. Conclusions: Continuous and deliberate efforts for multidisciplinary care in prostate cancer will be required to optimize and improve the oncologic and functional outcomes of patients treated with salvage therapies in the future.
Todd M. Morgan, S. Boorjian, M. Buyyounouski et al.
Purpose: The summary presented herein covers recommendations on salvage therapy for recurrent prostate cancer intended to facilitate care decisions and aid clinicians in caring for patients who have experienced a recurrence following prior treatment with curative intent. This is Part II of a three-part series focusing on treatment delivery for non-metastatic biochemical recurrence (BCR) after primary radical prostatectomy (RP). Please refer to Part I for discussion of treatment decision-making and Part III for discussion of evaluation and management of recurrence after radiotherapy (RT) and focal therapy, regional recurrence, and oligometastasis. Materials and Methods: The systematic review that informs this Guideline was based on searches in Ovid MEDLINE (1946 to July 21, 2022), Cochrane Central Register of Controlled Trials (through August 2022), and Cochrane Database of Systematic Reviews (through August 2022). Update searches were conducted on July 26, 2023. Searches were supplemented by reviewing electronic database reference lists of relevant articles. Results: In a collaborative effort between AUA, ASTRO, and SUO, the Salvage Therapy for Prostate Cancer Panel developed evidence- and consensus-based guideline statements to provide guidance for the care of patients who experience BCR after initial definitive local therapy for clinically localized disease. Conclusions: Optimizing and personalizing the approach to salvage therapy remains an ongoing area of work in the field of genitourinary oncology and represents an area of research and clinical care that requires well-coordinated, multi-disciplinary efforts.
C. Deville, Sophia C. Kamran, Scott C. Morgan et al.
PURPOSE Our purpose was to develop a summary of recommendations regarding the management of patients with clinically localized prostate cancer based on the American Urologic Association/ ASTRO Guideline on Clinically Localized Prostate Cancer. METHODS The American Urologic Association and ASTRO convened a multidisciplinary, expert panel to develop recommendations based on a systematic literature review using an a priori defined consensus-building methodology. The topics covered were risk assessment, staging, risk-based management, principles of management including active surveillance, surgery, radiation, and follow-up after treatment. Presented are recommendations from the guideline most pertinent to radiation oncologists with an additional statement on health equity, diversity, and inclusion related to guideline panel composition and the topic of clinically localized prostate cancer. SUMMARY Staging, risk assessment, and management options in prostate cancer have advanced over the last decade and significantly affect shared decision-making for treatment management. Current advancements and controversies discussed to guide staging, risk assessment, and treatment recommendations include the use of advanced imaging and tumor genomic profiling. An essential active surveillance strategy includes prostate-specific antigen monitoring and periodic digital rectal examination with changes triggering magnetic resonance imaging and possible biopsy thereafter and histologic progression or greater tumor volume prompting consideration of definitive local treatment. The panel recommends against routine use of adjuvant radiation therapy (RT) for patients with prostate cancer after prostatectomy with negative nodes and an undetectable prostate-specific antigen, while acknowledging that patients at highest risk of recurrence were relatively poorly represented in the 3 largest randomized trials comparing adjuvant RT to early salvage and that a role may exist for adjuvant RT in selected patients at highest risk. RT for clinically localized prostate cancer has evolved rapidly, with new trial results, therapeutic combinations, and technological advances. The recommendation of moderately hypofractionated RT has not changed, and the updated guideline incorporates a conditional recommendation for the use of ultrahypofractionated treatment. Health disparities and inequities exist in the management of clinically localized prostate cancer across the continuum of care that can influence guideline concordance.
J. Eastham, G. Auffenberg, D. Barocas et al.
Purpose: The summary presented herein represents Part III of the three-part series dedicated to Clinically Localized Prostate Cancer: AUA/ASTRO Guideline, discussing principles of radiation and offering several future directions of further relevant study in patients diagnosed with clinically localized prostate cancer. Please refer to Parts I and II for discussion of risk assessment, staging, and risk-based management (Part I), and principles of active surveillance and surgery and follow-up (Part II). Materials and Methods: The systematic review utilized to inform this guideline was conducted by an independent methodological consultant. A research librarian conducted searches in Ovid MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. The methodology team supplemented searches of electronic databases with the studies included in the prior AUA review and by reviewing reference lists of relevant articles. Results: The Clinically Localized Prostate Cancer Panel created evidence- and consensus-based guideline statements to aid clinicians in the management of patients with clinically localized prostate cancer. Statements regarding management of patients using radiation therapy as well as important future directions of research are detailed herein. Conclusions: This guideline aims to inform clinicians treating patients with clinically localized prostate cancer. Continued research and publication of high-quality evidence from future trials will be essential to further improve care for these men.
M. Libralato, R. Gerasimov, L. Bedin et al.
We present observations of the two closest globular clusters, NGC 6121 and NGC 6397, taken with the NIRISS detector of JWST. The combination of our new JWST data with archival Hubble Space Telescope (HST) images allows us to compute proper motions, disentangle cluster members from field objects, and probe the main sequence (MS) of the clusters down to <0.1 $M_\odot$ as well as the brighter part of the white-dwarf sequence. We show that theoretical isochrones fall short in modeling the low-mass MS and discuss possible explanations for the observed discrepancies. Our analysis suggests that the lowest-mass members of both clusters are significantly more metal-rich and oxygen-poor than their higher-mass counterparts. It is unclear whether the difference is caused by a genuine mass-dependent chemical heterogeneity, low-temperature atmospheric processes altering the observed abundances, or systematic shortcomings in the models. We computed the present-day local luminosity and mass functions of the two clusters; our data reveal a strong flattening of the mass function indicative of a significant preferential loss of low-mass stars in agreement with previous dynamical models for these two clusters. We have made our NIRISS astro-photometric catalogs and stacked images publicly available to the community.
F. Niederhofer, A. Bellini, V. Kozhurina-Platais et al.
We present proper motion (PM) measurements for a sample of 23 massive star clusters within the Large Magellanic Cloud using multi-epoch data from the Hubble Space Telescope (HST). We combined archival data from the ACS/WFC and WFC3/UVIS instruments with observations from a dedicated HST programme, resulting in time baselines between 4.7 and 18.2 yr available for PM determinations. For bright well-measured stars, we achieved nominal PM precisions of 55 $μ$as/yr down to 11 $μ$as/yr . To demonstrate the potential and limitations of our PM data set, we analysed the cluster NGC 1850 and showcase a selection of different science applications. The precision of the PM measurements allows us to disentangle the kinematics of the various stellar populations that are present in the HST field. The cluster has a centre-of-mass motion that is different from the surrounding old field stars and also differs from the mean motion of a close-by group of very young stars. We determined the velocity dispersion of field stars to be 0.128 +/- 0.003 mas/yr (corresponding to 30.3 +/- 0.7 km/s). The velocity dispersion of the cluster inferred from the PM data set most probably overestimates the true value, suggesting that the precision of the measurements at this stage is not sufficient for a reliable analysis of the internal kinematics of extra-galactic star clusters. Finally, we exploit the PM-cleaned catalogue of likely cluster members to determine any radial segregation between fast and slowly-rotating stars, finding that the former are more centrally concentrated. With this paper, we also release the astro-photometric catalogues for each cluster.
Kazumi Murata, Tsutomu T. Takeuchi
We propose a regularization-based deblurring method that works efficiently for galaxy images. The spatial resolution of a ground-based telescope is generally limited by seeing conditions and much worse than space-based telescopes. This circumstance has generated considerable research interest in restoration of spatial resolution. Since image deblurring is a typical inverse problem and often ill-posed, solutions tend to be unstable. To obtain a stable solution, much research has adopted regularization-based methods for image deblurring, but the regularization term is not necessarily appropriate for galaxy images. Although galaxies have an exponential or Sersic profile, the conventional regularization assumes the image profiles to behave linear in space. The significant deviation between the assumption and real situation leads to blurring the images and smoothing out the detailed structures. Clearly, regularization on logarithmic, i.e. magnitude domain, should provide a more appropriate assumption, which we explore in this study. We formulate a problem of deblurring galaxy images by an objective function with a Tikhonov regularization term on magnitude domain. We introduce an iterative algorithm minimizing the objective function with a primal-dual splitting method. We investigate the feasibility of the proposed method using simulation and observation images. In the simulation, we blur galaxy images with a realistic point spread function and add both Gaussian and Poisson noises. For the evaluation with the observed images, we use galaxy images taken by the Subaru HSC-SSP. Both of these evaluations show that our method successfully recovers the spatial resolution of the images and significantly outperforms the conventional methods. The code is publicly available from the Github ( https://github.com/kzmurata-astro/PSFdeconv_amag ).
M. Libralato, A. Bellini, E. Vesperini et al.
A number of studies based on data collected by the $\textit{Hubble Space Telescope}$ ($\textit{HST}$) GO-13297 program "HST Legacy Survey of Galactic Globular Clusters: Shedding UV Light on Their Populations and Formation" have investigated the photometric properties of a large sample of Galactic globular clusters and revolutionized our understanding of their stellar populations. In this paper, we expand previous studies by focusing our attention on the stellar clusters' internal kinematics. We computed proper motions for stars in 56 globular and one open clusters by combining the GO-13297 images with archival $\textit{HST}$ data. The astro-photometric catalogs released with this paper represent the most complete and homogeneous collection of proper motions of stars in the cores of stellar clusters to date, and expand the information provided by the current (and future) $\textit{Gaia}$ data releases to much fainter stars and into the crowded central regions. We also census the general kinematic properties of stellar clusters by computing the velocity-dispersion and anisotropy radial profiles of their bright members. We study the dependence on concentration and relaxation time, and derive dynamical distances. Finally, we present an in-depth kinematic analysis of the globular cluster NGC 5904.
Yang-wei Zhang, Yang Huang, Jin-ming Bai et al.
Building a large sample of kiloparsec (kpc)-scale dual active galactic nuclei (AGNs) amongst merging galaxies is of vital importance to understand the co-evolution between host galaxies and their central super massive black holes (SMBHs). Doing so, with just such a sample, we have developed an innovative method of systematically searching and identifying dual AGNs of amongst kpc scale merging galaxies and selected 222 candidates at redshifts $\leqslant$ 0.25. All the selected candidates have FIRST radio detection and at least one of two cores previously revealed as AGN spectroscopically. We report the first results from A SysTematic seaRch fOr Dual Agns in meRgINg Galaxies (ASTRO-DARING), which consist of spatially resolved long-slit spectroscopic observations of 41 targets selected from our merging galaxies sample carried out between November 2014 and February 2017, using the Yunnan Faint Object Spectrograph and Camera (YFOSC) mounted on the 2.4 meter telescope in Lijiang of Yunnan Observatories. Of these 16 are likely dual AGNs and 15 are newly identified. The efficiency of ASTRO-DARING is thus nearly 40 per cent. With this method, we plan to build the first even sample of more than 50 dual AGNs constructed using a consistent approach. Further analysis of the dual AGN sample shall provide vital clues for understanding the co-evolution of galaxies and SMBHs.
Tadayuki Takahashi, M. Kokubun, K. Mitsuda et al.
Abstract. The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month.
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