Prototype solar heating and cooling systems, including potable hot water

Progress made in the development, delivery, and support of two prototype solar heating and cooling systems including potable hot water is reported. The system consists of the following subsystems: collector, auxiliary heating, potable hot water, storage, control, transport, and government-furnished site data acquisition. A comparison of the proposed Solaron Heat Pump and Solar Desiccant Heating and Cooling Systems, installation drawings, data on the Akron House at Akron, Ohio, and other program activities are included

Preliminary design of flight hardware for two-phase fluid research

This study defined the preliminary designs of flight software for the Space Shuttle Orbiter for three two-phase fluid research experiments: (1) liquid reorientation - to study the motion of liquid in tanks subjected to small accelerations; (2) pool boiling - to study low-gravity boiling from horizontal cylinders; and (3) flow boiling - to study low-gravity forced flow boiling heat transfer and flow phenomena in a heated horizontal tube. The study consisted of eight major tasks: reassessment of the existing experiment designs, assessment of the Spacelab facility approach, assessment of the individual carry-on approach, selection of the preferred approach, preliminary design of flight hardware, safety analysis, preparation of a development plan, estimates of detailed design, fabrication and ground testing costs. The most cost effective design approach for the experiments is individual carry-ons in the Orbiter middeck. The experiments were designed to fit into one or two middeck lockers. Development schedules for the detailed design, fabrication and ground testing ranged from 15 1/2 to 18 months. Minimum costs (in 1981 dollars) ranged from $463K for the liquid reorientation experiment to$998K for the pool boiling experiment

LOFAR observations of 4C+19.44. On the discovery of low frequency spectral curvature in relativistic jet knots

We present the first LOFAR observations of the radio jet in the quasar 4C+19.44 (a.k.a. PKS 1354+19) obtained with the long baselines. The achieved resolution is very well matched to that of archival Jansky Very Large Array (JVLA) observations at higher radio frequencies as well as the archival X-ray images obtained with {\it Chandra}. We found that, for several knots along the jet, the radio flux densities measured at hundreds of MHz lie well below the values estimated by extrapolating the GHz spectra. This clearly indicates the presence of spectral curvature. Radio spectral curvature has been already observed in different source classes and/or extended radio structures and it has been often interpreted as due to intrinsic processes, as a curved particle energy distribution, rather than absorption mechanisms ({ Razin-Tsytovich} effect, free-free or synchrotron self absorption to name a few). Here we discuss our results according to the scenario where particles undergo stochastic acceleration mechanisms also in quasar jet knots.Comment: 13 pages, 4 tables, 4 figures, pre-proof version, published on the Astrophysical Journal (Harris, et al. 2019 ApJ, 873, 21

Carbon radio recombination lines from gigahertz to megahertz frequencies towards Orion A

Context. The combined use of carbon radio recombination lines (CRRLs) and the 158 $\mu$m-[CII] line is a powerful tool for the study of the energetics and physical conditions (e.g., temperature and density) of photodissociation regions (PDRs). However, there are few observational studies that exploit this synergy. Aims. Here we explore the relation between CRRLs and the 158 $\mu$m-[CII] line in light of new observations and models. Methods. We present new and existing observations of CRRLs in the frequency range 0.15--230 GHz with ALMA, VLA, the GBT, Effelsberg 100m, and LOFAR towards Orion~A (M42). We complement these observations with SOFIA observations of the 158 $\mu$m-[CII] line. We studied two PDRs: the foreground atomic gas, known as the Veil, and the dense PDR between the HII region and the background molecular cloud. Results. In the Veil we are able to determine the gas temperature and electron density, which we use to measure the ionization parameter and the photoelectric heating efficiency. In the dense PDR, we are able to identify a layered PDR structure at the surface of the molecular cloud to the south of the Trapezium cluster. There we find that the radio lines trace the colder portion of the ionized carbon layer, the C$^{+}$/C/CO interface. By modeling the emission of the $158$~$\mu$m-[CII] line and CRRLs as arising from a PDR we derive a thermal pressure $>5\times10^{7}$ K cm$^{-3}$ and a radiation field $G_{0}\approx10^{5}$ close to the Trapezium. Conclusions. This work provides additional observational support for the use of CRRLs and the 158 $\mu$m-[CII] line as complementary tools to study dense and diffuse PDRs, and highlights the usefulness of CRRLs as probes of the C$^{+}$/C/CO interface.Comment: 18 pages, 16 figures, accepted for publication in A&

Spectroscopy with the Engineering Development Array: cold H+^{+} at 63 MHz towards the Galactic Centre

The Engineering Development Array (EDA) is a single test station for Square Kilometre Array (SKA) precursor technology. We have used the EDA to detect low-frequency radio recombination lines (RRLs) from the Galactic Centre region. Low-frequency RRLs are an area of interest for future low-frequency SKA work as these lines provide important information on the physical properties of the cold neutral medium. In this project we investigate the EDA, its bandpass and the radio frequency interference environment for low-frequency spectroscopy. We present line spectra from 30 to 325 MHz for the Galactic Centre region. The decrease in sensitivity for the EDA at the low end of the receiver prevents carbon and hydrogen RRLs to be detected below 40 and 60 MHz respectively. RFI strongly affects frequencies in the range 276-292, 234-270, 131-138, 95-102 and below 33 MHz. Cn$\alpha$ RRLs were detected in absorption for quantum levels n = 378 to 550 (39-121 MHz) and in emission for n = 272 to 306 (228-325 MHz). Cn$\beta$ lines were detected in absorption for n = 387 to 696 (39-225 MHz). Hn$\alpha$ RRLs were detected in emission for n = 272 to 480 (59-325 MHz). Hn$\beta$ lines were detected for n = 387 to 453 (141-225 MHz). The stacked Hn$\alpha$ detection at 63 MHz is the lowest frequency detection made for hydrogen RRLs and shows that a cold (partially) ionized medium exists along the line of sight to the Galactic Centre region. The size and velocity of this cold H$^{+}$ gas indicates that it is likely associated with the nearby Riegel-Crutcher cloud.Comment: 18 pages, 6 figures and 5 table

Post-discharge Telemonitoring of Physical Activity, Vital Signs, and Patient-Reported Symptoms in Older Patients Undergoing Cancer Surgery

BACKGROUND: Postoperative home monitoring could potentially detect complications early, but evidence in oncogeriatric surgery is scarce. Therefore, we evaluated whether post-discharge physical activity, vital signs, and patient-reported symptoms are related to post-discharge complications and hospital readmissions in older patients undergoing cancer surgery. METHODS: In this observational cohort study, we monitored older patients (≥65 years of age) undergoing cancer surgery, for 2 weeks post-discharge using tablet-based applications and connected devices. Outcome measures were post-discharge complications and readmissions; physical activity and patient-reported symptoms over time; and threshold violations for physical activity (step count 38°C; blood pressure 150/100 mmHg; heart rate 100 bpm; weight -5% or +5% of weight at discharge); and patient-reported symptoms (pain score greater than the previous day; presence of dyspnea, vomiting, dizziness, fever). RESULTS: Of 58 patients (mean age 72 years), 24 developed a post-discharge complication and 13 were readmitted. Measured parameters indicated 392 threshold violations out of 5379 measurements (7.3%) in 40 patients, mostly because of physical inactivity. Patients with readmissions had lower physical activity at discharge and at day 9 after discharge and violated a physical activity threshold more often. Patients with post-discharge complications had a higher median pain score compared with patients without these adverse events. No differences in threshold violations of other parameters were observed between patients with and without post-discharge complications and readmissions. CONCLUSION: Our results show the potential of telemonitoring older patients after cancer surgery but confirm that detecting post-discharge complications is complex and multifactorial

Perioperative telemonitoring of older adults with cancer:Can we connect them all?

OBJECTIVES: Although the increasing cancer incidence in older patients is widely recognised, older patients remain underrepresented in clinical cancer trials and eHealth studies. The aim of this research is to identify technological and patient-related barriers to inclusion of this population in a clinical eHealth study. MATERIAL AND METHODS: This is a retrospective analysis of a prospective cohort study with older patients (≥ 65 years) undergoing cancer-related surgery, who were identified for a perioperative telemonitoring study. Reasons for ineligibility and refusal had been prospectively registered. Characteristics and postoperative outcomes were compared between participants and non-participants. RESULTS: Between May 2018 and March 2020, 151 patients were assessed for eligibility, resulting in 65 participants and 86 non-participants. The main reason for ineligibility was lack of internet access at home (n = 16), while main reasons for refusal were perceived high mental burden (n = 46) and insufficient digital skills (n = 12). Compared with participants, non-participants were significantly older (mean age 75 vs. 73, p = 0.01); more often female (64% vs. 35%, p = 0.00), unmarried (42% vs. 8%, p = 0.01) living alone (38% vs. 19%, p = 0.02); had a higher ASA classification (43% vs. 19%, p = 0.00); often had polypharmacy (67% vs. 43%, p = 0.00); and were more often discharged to skilled nursing facilities (0% vs. 15%, p = 0.00). CONCLUSION: Our results confirm the underrepresentation of older female patients with little support from a partner and higher comorbidity. We should be aware of technological and patient-related barriers to including older adults with cancer, in order to avoid further dividing patients with low and high digital health literacy

An Investigation of ISR Coordination and Information Presentation Strategies to Support Expeditionary Strike Groups

12th ICCRTS, Adapting C2 to the 21st CenturyThis paper describes a planned experiment based on the combined research of the Adaptive Architectures for Command and Control (A2C2) and the Command-21 programs, both of which are sponsored by the Office of Naval Research. In line with the theme of this year’s symposium, “Adapting C2 to the 21st Century,” in this research we focus on the nexus of organizational design and information presentation strategies — both of which are undergoing dramatic changes in form and function within the US military. The formation of Expeditionary Strike Groups (ESGs) provides one example of the transformational vision provided in the Naval Operating Concept where Strike Groups offer the potential to revolutionize naval warfare in the littoral region. The ESG provides a flexible force package, capable of tailoring itself to accomplish a wide variety of mission sets. In this effort, we seek to explore how ESGs with alternative structures and processes, in this case specifically related to incorporation of an intelligence, surveillance, and reconnaissance (ISR) officer and different information presen-tation strategies, can affect performance and information flow in an information rich planning and execution environment