A new 1.4 GHz 19-element, dual-polarization, cryogenic phased array feed (PAF) radio astronomy receiver has been developed for the Robert C. Byrd Green Bank Telescope (GBT) as part of FLAG (Focal L-band Array for the GBT) project. Commissioning observations of calibrator radio sources show that this receiver has the lowest reported beamformed system temperature (T sys ) normalized by aperture efficiency (η) of any phased array receiver to date. The measured T sys /η is 25.4 ± 2.5 K near 1350 MHz for the boresight beam, which is comparable to the performance of the current 1.4 GHz cryogenic single feed receiver on the GBT. The degradation in T sys /η at ∼ 4 (required for Nyquist sampling) and ∼ 8 offsets from the boresight is, respectively, ∼ 1% and ∼ 20% of the boresight value. The survey speed of the PAF with seven formed beams is larger by a factor between 2.1 and 7 compared to a single beam system depending on the observing application. The measured performance, both in frequency and offset from boresight, qualitatively agree with predictions from a rigorous electromagnetic model of the PAF. The astronomical utility of the receiver is demonstrated by observations of the pulsar B0329+54 and an extended H ii region, the Rosette Nebula. The enhanced survey speed with the new PAF receiver will enable the GBT to carry out exciting new science, such as more efficient observations of diffuse, extended neutral hydrogen emission from galactic in-flows and searches for Fast Radio Bursts.

Recent data have shown that the G-protein-coupled receptor GPR54 (also known as KiSS-1 receptor) regulates GnRH release from the hypothalamus. This essential role of GPR54 in controlling the hypothalamic-pituitary-gonadal axis makes it an attractive target for therapeutic intervention in reproductive and cancer medicine. Currently, there are no small-molecule modulators of GPR54 function for experimental or clinical use. To identify small-molecule compounds that modify GPR54 signal transduction, the authors have adapted a cell-based functional assay for high-throughput screening (HTS) using a commercially available homogeneous time-resolved fluorescence assay for inositol phosphate accumulation. They generated stable Chinese hamster ovary cell transfectants that express human GPR54 for use in this assay. After optimization in an automated HTS environment, they screened a library of 110,000 small-molecule compounds using 2 protocols, one to identify agonists and one to identify antagonists. Hits obtained in the primary screen were confirmed to be active in secondary in vitro assays. Compounds identified as agonists or antagonists from HTS and secondary screening will be characterized to identify agents with the potential to be developed as novel orally active agents to treat hormone-dependent disorders such as abnormal puberty, infertility, endometriosis, and sex steroid-dependent tumors.

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We present the results of commissioning observations for a new digital beam-forming back end for the Focal plane L-band Array for the Robert C. Byrd Green Bank Telescope (FLAG), a cryogenically cooled Phased Array Feed (PAF) with the lowest measured T sys/η of any PAF outfitted on a radio telescope to date. We describe the custom software used to apply beam-forming weights to the raw element covariances to create research-quality spectral-line images for the new fine-channel mode, study the stability of the beam weights over time, characterize FLAG’s sensitivity over a frequency range of 150 MHz, and compare the measured noise properties and observed distribution of neutral hydrogen emission from several extragalactic and Galactic sources with data obtained with the current single-pixel L-band receiver. These commissioning runs establish FLAG as the preeminent PAF receiver currently available for spectral-line observations on the world’s major radio telescopes.

Patient experience is a core component of the Institute for Healthcare Improvement Triple Aim for health care improvement. Although resident physicians must meet quality improvement (QI) competencies prior to graduation, QI training during residency may not adequately prepare residents to improve patient and family experience. We describe an active learning QI curriculum engaging 3 Patient and Family Advisors as partners alongside 15 resident physicians. This partnership proved to be a meaningful experience for both groups, with the development of mutual respect and insight into the contributions that patients and families bring to solving problems in health care quality.