Radar Shape Modeling of Binary Near-Earth Asteroid (385186) 1994 AW1

(385186) 1994 AW1 is a potentially hazardous asteroid and the first near-Earth asteroid suspected to be a binary [1,2]. It made a close approach to Earth in July 2015 getting as close as 25 lunar distances on the 15th. This flyby was a great opportunity for observations in photometry [3] and radar. Continuous-wave (CW) and Delay-Doppler imaging modes were used, first at Goldstone for the 14-19 July period (0.066-0.700 au), and then by Arecibo for 20-30 July (0.075-0.126 au). A range resolution of 150 m was achieved at Goldstone in bistatic configuration with Green Bank Telescope, while monostatic observations in S-band (2380 MHz, 12.6 cm) at Arecibo were obtained at resolutions of 30 m and 75 m. The rotation period of the primary (2.52 h) and orbital period of the secondary (22 h) derived from optical light curves were confirmed by these observations. The primary is about 600 m in diameter and the secondary is about half of the primary's size. A more recent but relatively distant approach (July 8, 2022; 0.11 au) allowed CW spectra to be obtained at Goldstone [4]. We also obtained new light curves on 2023 January 13-24 while it was at V ~16-17 mag. We used the TRAPPIST-South (I40, Chile) and -North (Z53, Morocco) [5] to gather 10 light curves in total. For four of them, brightness drops indicate mutual events between 1994 AW1 and its satellite. We then used our radar and optical datasets with SHAPE [6] to perform shape modeling of the primary component. We will present our preliminary 3D shape model, pole coordinates and system density. References: [1] Pravec, P. and Hahn, G. (1997) Icarus, 127 [2] Mottola, S. et al. (1995) LPIC, 26 [3] Warner D. B. (2016) MPB, 43 [4] Brozovic, M. et al. (2022) DPS 54. [5] Jehin, E. et al. (2011) The Messenger 145, 2–6. [6] Magri, C. et al. (2007) Icarus 186, 152-177

Comparing resection and stereotactic body radiation therapy for hepatocellular carcinoma with macrovascular invasion:A propensity score matched study.

Background: Macrovascular invasion (MVI) in hepatocellular carcinoma (HCC) patients is a poor prognostic factor. Current guidelines endorse systemic therapy for MVI. Local therapies present a potential for obliteration of MVI and improved survival. Surgery has been the standard local therapy at our institution, and stereotactic body radiotherapy (SBRT) has emerged as an alternative local therapy for this patient population. Methods: In this retrospective study, one-to-one optimal pair propensity score matching was used to compare outcomes of HCC patients with MVI who underwent surgery or received SBRT. Matching was done based on sex, age, ECOG, cirrhosis presence, Child-Pugh class, number of tumours, tumour volume, alpha-fetoprotein level, ALBI score, Japanese Classification of portal vein invasion, and hepatic vein invasion. Overall survival was estimated using the Kaplan-Meier method and between group differences determined using the log-rank test. The cumulative incidence of recurrence, accounting for the competing risk of death, was compared using Gray’s test. Results: Ninety of 193 patients were included after matching (45 patients in both the surgery and SBRT groups) (Table). The SBRT group had a median OS of 15 months (95% CI: 10-38), while in the surgery group it was 24 months (95% CI: 11-81). Comparing the 12-, 36-, and 60-month overall survival (OS) rates between the SBRT group (57%, 33%, 15%) and the surgery group (58%, 37%, 34%), there was no statistically significant differences (p=0.16); the 5-year OS was double in the surgical resection group. The 12-, 36-, and 60-month cumulative incidence of HCC recurrence in the SBRT group (47%, 73%, 75%) was comparable to the surgery group (69%, 69%, 69%) (p=0.89). Conclusions: Long term survival is possible in patients with HCC and MVI in a substantial minority of patients with HCC and MVI treated with local therapies. There was no statistical difference in outcomes; however, surgical resection resulted in numerically longer survival outcomes compared to SBRT after propensity score adjustment. There is rationale for investigating both local therapies with systemic therapies in future clinical trials

Outcomes of Stereotactic Body Radiotherapy Compared with Surgical Resection in Patients with Hepatocellular Carcinoma and Macrovascular Invasion:A Propensity Score-Matched Analysis

INTRODUCTION: Patients with advanced hepatocellular carcinoma (HCC) and macrovascular invasion (MVI) are recommended to receive systemic therapy according to guidelines. Stereotactic body radiotherapy (SBRT) and surgery are increasingly used in this patient population. This study compares outcomes from these local treatments.METHODS:Patients diagnosed with HCC with MVI and treated with surgery or SBRT between 1999 and 2022 were included. Propensity score matching minimized bias from confounders. Overall survival (OS) was analyzed using the Kaplan-Meier method,. and local, regional, and distant recurrences were assessed via competing risk methods. Univariable and multivariable analyses adjusted by the Lasso method evaluated OS predictors.RESULTS: Among 175 patients, 38 underwent surgery and 137 received SBRT. The median age was 61 years, tumor volume was 158.6 cc, and α-fetoprotein level was 197 IU/mL. Most surgical patients had major resection (74%) via an open approach (97%). The median biologically effective dose (BED) for SBRT was 53.7 Gy. After matching, 35 patients per group had a median OS of 16 months. Local failure was higher in the SBRT group (20%) than in the surgery group (12%) at 1 year (p = 0.028). Distant failure was more frequent in surgery (54%) compared with SBRT (17%) [p = 0.003]. Excluding SBRT patients receiving adjuvant systemic therapy did not change the results. In-hospital mortality was 9% post-surgery and 14% experienced post-SBRT liver impairment.CONCLUSION: Both surgery and SBRT offer good long-term OS and control. Surgery provides better local control, while SBRT had lower distant relapse. While SBRT has acceptable toxicity, surgery carries a significant mortality risk.</p

Arecibon planetaarisen tutkan Maan lähiasteroidihavainnot: 2017 joulukuu - 2019 joulukuu

We successfully observed 191 near-Earth asteroids using the Arecibo Observatory's S-band planetary radar system from 2017 December through 2019 December. We present radar cross sections for 167 asteroids; circular-polarization ratios for 112 asteroids based on Doppler-echo-power spectra measurements; and radar albedos, constraints on size and spin periods, and surface-feature and shape evaluation for 37 selected asteroids using delay-Doppler radar images with a range resolution of 75 m or finer. Out of 33 asteroids with an estimated effective diameter of at least 200 m and sufficient image quality to give clues of the shape, at least 4 (∼12%) are binary asteroids, including 1 equal-mass binary asteroid, 2017 YE5, and at least 10 (∼30%) are contact-binary asteroids. For 5 out of 112 asteroids with reliable measurements in both circular polarizations, we measured circular-polarization ratios greater than 1.0, which could indicate that they are E-type asteroids, while the mean and the 1σ standard deviation were 0.37 ± 0.23. Further, we find a mean opposite-sense circular-polarization radar albedo of 0.21 ± 0.11 for 41 asteroids (0.19 ± 0.06 for 11 S-complex asteroids). We identified two asteroids, 2011 WN15 and (505657) 2014 SR339, as possible metal-rich objects based on their unusually high radar albedos, and discuss possible evidence of water ice in 2017 YE5.Peer reviewe

The Human Cell Atlas White Paper

The Human Cell Atlas (HCA) will be made up of comprehensive reference maps of all human cells - the fundamental units of life - as a basis for understanding fundamental human biological processes and diagnosing, monitoring, and treating disease. It will help scientists understand how genetic variants impact disease risk, define drug toxicities, discover better therapies, and advance regenerative medicine. A resource of such ambition and scale should be built in stages, increasing in size, breadth, and resolution as technologies develop and understanding deepens. We will therefore pursue Phase 1 as a suite of flagship projects in key tissues, systems, and organs. We will bring together experts in biology, medicine, genomics, technology development and computation (including data analysis, software engineering, and visualization). We will also need standardized experimental and computational methods that will allow us to compare diverse cell and tissue types - and samples across human communities - in consistent ways, ensuring that the resulting resource is truly global. This document, the first version of the HCA White Paper, was written by experts in the field with feedback and suggestions from the HCA community, gathered during recent international meetings. The White Paper, released at the close of this yearlong planning process, will be a living document that evolves as the HCA community provides additional feedback, as technological and computational advances are made, and as lessons are learned during the construction of the atlas

Brazoria County News Photography Collection (University of North Texas) Teaching Activity Plan and Public Program Grant Proposal

Informatio

Detection of OH 18 cm Emission from Comet C/2020 F3 NEOWISE Using the Arecibo Telescope

Abstract We report the detection of emission from the OH 18 cm Λ-doublet transitions toward Comet C/2020 F3 NEOWISE using the Arecibo Telescope. The antenna temperatures are 113 ± 3 mK for the 1667 MHz line and 57 ± 3 mK for the 1665 MHz line. The beam-averaged OH column density (centered on the comet nucleus) derived from the 1667 transition is N OH = (1.11 ± 0.06) × 1013 cm−2. We implemented the Haser model to derive an OH production rate. The estimated OH production rate using the 1667 transition is Q OH = (3.6 ± 0.6) × 1028 s−1, a factor of 2.4 lower than optically derived values for the same observing day, the difference of which is likely explained by quenching.</jats:p

Arecibo Science Highlights of Observatory Planetary Radar Observations: 2019-2020

&amp;lt;p&amp;gt;We present a summary of the radar experiments performed with the Arecibo Observatory Planetary Radar system during 2019-2020.&amp;amp;#160; Located in Puerto Rico (18&amp;amp;#176; 20' 36.6&amp;quot; N, 66&amp;amp;#176; 45' 11.1&amp;quot; W) the Arecibo Observatory S-band (2380 MHz) radar system is capable of transmitting up to 1MW of power and uses the William E Gordon Telescope antenna of 305 m. The planetary radar science group focuses on performing follow-up (post discovery) observations of&amp;amp;#160; known small bodies as well as recently discovered ones. Priority is given to objects on the CNEOS Sentry impact risk list, those classified as Potentially Hazardous (PHA&amp;amp;#8217;s) and those that are potential spacecraft mission targets (NHATS). Although currently operating at 35% power capacity, Arecibo has observed 92 objects since September 2019 to abstract submission date, distributed as: 61&amp;amp;#160; recently discovered objects, 28 PHA&amp;amp;#8217;s, 2 planets and 1 comet. We present here some science highlights of&amp;amp;#160; this year's observations of near-Earth objects (NEOs), including radar delay-Doppler images of 2020BX12, 2011WN15, 481394 (2006 SF6) and 162082 (1998HL1).&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Introduction&amp;lt;/strong&amp;gt;&amp;lt;br /&amp;gt;The Arecibo Observatory is the largest and most powerful planetary radar system in the world, successfully observing&amp;amp;#160; up to 130 asteroids a year. Funded by the NASA-NEO Observations program, the ground-based observations done using the S-band (2380 MHz, 12.6 cm) radar systems are a highly cost effective and rapid tool to constrain physical and dynamical properties of the targets in comparison to space missions. This Instrument has the capability of transmitting a signal with or without&amp;amp;#160; phase modulation, providing extremely accurate astrometry measurements (range and radial velocity) on newly discovered objects, and track changes in the orbit of previously observed ones, such as those due to non-gravitational perturbations. Besides orbital characterization, radar data provides constraints on the object's size and rotation rate, is responsible for the discovery of satellites [1,2]&amp;amp;#160; and for some cases can identify the shape and near-surface (meter-scale) structures up to a few wavelengths deep.&amp;amp;#160;&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Methods&amp;lt;/strong&amp;gt;&amp;lt;br /&amp;gt;The S-band system transmits a circularly polarized wave, and receives both the same-sense circular (SC) and opposite-sense circular polarization (OC) as transmitted. Radar observations usually start by a continuous-wave measurement to obtain the Doppler frequency spectrum of the echo. The measured Doppler spectrum bandwidth provides initial limits for rotation period and the object&amp;amp;#8217;s apparent diameter. From the measured received backscattered power in these two orthogonal states of polarization, it's possible to calculate the target's circular polarization ratio. Defined as the ratio of the SC and OC echo and commonly used as an indicator of the surface reflection properties. For targets with a relatively high signal-to-noise-ratio (SNR) we use phase modulation to produce delay-Doppler images, with range resolution as fine as 7.5 m per pixel in some cases. These images aid in the estimation of objects' diameter and provide an idea of the body's shape.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Results&amp;lt;/strong&amp;gt;&amp;lt;br /&amp;gt;Some highlights of our observations include: 162082 (1998 HL1) observed on October 25-28, 2019 with a delay-Doppler resolution of 75 m/px, its apparent diameter is estimated at 270 m, and its rotation period at approximately 11 hrs. Contact binary 481394 (2006SF6) was observed on November 11-15, 2019, with a delay-Doppler resolution of 7.5 m/px showing a maximum visible extent of 240 m. The rotation period is estimated to be 11.3 hrs and&amp;amp;#160; it was observed at various orientations. 2011 WN15 was observed on December 12-13, 2019, with a delay-Doppler resolution of 7.5 m/px providing an estimate on diameter of 900 m, and a rotation period of up to 4 hours. 2020 BX12 observation on February 4-5, 2020, led to the discovery of a secondary body, images with delay-Doppler resolution of 7.5 m/px, showed a diameter of 165 m for the primary and no more than 70 m for the secondary. The apparent rotation period for the primary is about 2.8 hrs and 49 hrs or less for the secondary.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Acknowledgements:&amp;lt;/strong&amp;gt;&amp;lt;br /&amp;gt;The Arecibo Planetary Radar Program is fully supported by NASA&amp;amp;#8217;s Near-Earth Object Observations Program in NASA&amp;amp;#8217;s Planetary Defense Coordination Office through grant no. 80NSSC19K0523 awarded to University of Central Florida (UCF). UCF manages the National Science Foundation facility under a cooperative agreement with Yang Enterprises, Inc. and Universidad Ana G. M&amp;amp;#233;ndez.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;References&amp;lt;/strong&amp;gt;&amp;lt;br /&amp;gt;[1] Benner, L.A., Nolan, M.C., Margot, J., Brozovic, M., Ostro, S.J., Shepard, M.K., Magri, C., Giorgini, J.D. and Busch, M.W., 2008, September. Arecibo and Goldstone radar imaging of contact binary near-Earth asteroids. In DPS (pp. 25-03).&amp;lt;br /&amp;gt;[2] Rivera-Valentin, E.G., Taylor, P.A., Virkki, A. and Aponte-Hernandez, B., 2017. (163693) Atira. CBET, 4347, p.1.&amp;lt;/p&amp;gt;</jats:p