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BACKGROUND Low rates of heart failure (HF) hospitalizations were observed during the 2020 peak of the COVID-19 pandemic. It is unclear how this affected different racial and socioeconomic groups. It is also unknown whether the shift to telemedicine impacted disparities in follow-up or readmissions. OBJECTIVE To determine the effects of the COVID-19 pandemic on acute decompensated heart failure admissions and post-hospitalization follow-up for different socioeconomic as well as racial and ethnic groups. METHODS HF admissions during the initial peak of the pandemic (March 15–June 1, 2020) were compared to the same timeframe in 2019. Patients were stratified by race, ethnicity, and median neighborhood income. Hospital and ICU admission rates, inpatient mortality, 7-day follow-up, and 30-day readmissions were assessed. RESULTS Patients in 2020 had higher rates of ICU admission compared to 2019 (16.87% vs 10.96%; P=0.008). This trend was seen across all subgroups and was significant for patients from the highest income quartile (17.89% vs 10.99%; P=0.018) and white patients (16.59% vs 9.52%; P=0.007). While there was a trend towards higher inpatient mortality in 2020 versus 2019 (4.60% vs 2.53%; P=0.077), no difference was seen among different racial and socioeconomic groups. Telemedicine comprised 80.69% of 7-day follow-up in 2020, with improvement in 7-day follow-up rates (43.86% vs 32.58%; P CONCLUSIONS There were no major differences in HF admissions for different racial and socioeconomic groups during the COVID-19 pandemic. Inequalities in 7-day follow-up were reduced with the advent of telemedicine and decreased 30-day readmission for those who had follow-up.

AimTo describe and evaluate the psychosocial impact of the COVID-19 pandemic and measures to reduce the risk of transmission on patients with early-onset neuromuscular and neurological disorders (NMDs) and their families.DesignA mixed-methods study in which data were collected between 17 September 2020 and 31 December 2020 using a semi-structured telephone questionnaire developed specifically to meet research aims, and were analysed using quantitative methods and qualitative inductive thematic analysis.ParticipantsForty questionnaires were completed by patients with NMDs (eg, muscular dystrophies, spinal muscular atrophy) or their parent. 70% (n=28) of patients were male, aged 2–48 years. 90% (n=36) were wheelchair users; 72.5% (n=29) required long-term non-invasive or tracheostomy ventilation.ResultsStrict adherence to risk mitigation strategies, for example, shielding, were reported at the start of the pandemic. Over half continued some or all measures after official limitations were relaxed. 67.5% (n=27) reported changes to personal care assistance arrangements including temporary cessation of outside carers. Three themes were identified: (1) Concern regarding the health impact of COVID-19; (2) Perceptions of strategies to prevent SARS-CoV-2 transmission; (3) Psychological impact of the COVID-19 pandemic. The level and pervasiveness of frequently reported negative psychological effects, for example, anxiety and fear fluctuated, and were related to the perceived risk of COVID-19, concern about attending hospital, and perceived lack of access to intensive care management if severe COVID-19 infection occurred. Support, particularly from family and healthcare services, were considered to have positive psychosocial effects.ConclusionsMeasures to reduce transmission of COVID-19 have greatly affected patients with NMDs and their families. For most, negative psychosocial impacts have and will continue to improve, but this may depend on the incidence of further pandemic waves. Consistent, up-to-date and accessible information on clinical outcomes and risk mitigation must be provided to support patients’ physical and mental well-being.

Case Presentation: A 23-year-old previously healthy man presented with progressive dyspnea. Physical examination revealed jugular venous distension and lower extremity edema. Laboratory testing demonstrated elevated B-type natriuretic peptide (193 pg/mL) and normal high sensitivity troponin. Echocardiogram revealed small pericardial effusion, respiratory variation in diastolic flow across the mitral valve, diastolic septal bounce, and annulus reversus ( Figure ). The differential diagnosis for constrictive pericarditis was broadly considered in the context of a recent febrile illness and frequent travel to Hawaii and Vietnam; we included infectious, autoimmune, and malignant etiologies. Cardiac magnetic resonance imaging revealed thickening and diffuse enhancement in the pericardium as well as ventricular interdependence. Chest CT identified hilar and anterior mediastinal lymphadenopathy. Laboratory testing was positive for QuantiFERON gold and negative for COVID-19, HIV, and ANA. Transbronchial biopsy demonstrated non-necrotizing granulomas with negative acid-fast bacilli smear, culture, and polymerase chain reaction for mycobacterial DNA. Re-examination identified a red-brown plaque on the patient’s thigh; biopsy showed granulomatous inflammation and rod-shaped organism with positive FITE staining. A presumed unifying diagnosis was made of extrapulmonary tuberculosis (TB) complicated by constrictive pericarditis. Discussion: Despite being a primarily pulmonary disease, systemic involvement can occur with TB with the heart being one of the most common extrapulmonary sites. This case highlights 1) the utility of extra-cardiac diagnostic testing (e.g., dermatologic biopsy) in the diagnosis of constrictive pericarditis, and 2) the diagnostic challenge associated with extrapulmonary TB, particularly paucibacillary disease that requires a detailed social history with “out-of-the-box” thinking.

We report the results and analysis methods from field-testing the imaging calorimeter prototype for the Advanced Particle-astrophysics Telescope (APT) through an antarctic balloon flight (in the 2019 austral Antarctic balloon season) and through a CERN heavy-ion beam test in 2018. The Advanced Particle-astrophysics Telescope is a proposed space-based gamma- and cosmic-ray instrument that utilizes a novel distributed imaging calorimeter for both particle tracking and energy reconstruction. The imaging CsI calorimeter (ICC) consists of a CsI:Na scintillator read out by (WLS) fibers in both the x- and y-planes. To function both as a gamma-ray and cosmic-ray instrument APT must operate over a large dynamic range, from the single photon-election regime for low energy gamma-ray events to high-$Z$ cosmic-ray events. Analysis of data from a 150 mm x 150 mm prototype instrument (APTlite) on a piggy-back flight on the 2019 SuperTIGER-2.3 balloon instrument provided cosmic ray data that were used to demonstrate the key detector and electronics elements of the ICC. Significantly, analysis of flight data demonstrated the large dynamic range of the instrument, showing the possibility to reconstruct the nuclear charge through analysis of the scintillation tail of saturating high-Z cosmic-ray events by utilizing the deep memory depth available to the TARGET waveform digitizer electronics. Spatial reconstruction of events was performed using a two-sided Voigt profile demonstrating position localization within the imaging calorimeter plane to less 3 WLS fiber widths. Charge resolution was evaluated on a 50 mm x 50 mm prototype placed in the 150 GeV/nuc, A/Z = 2.2 CERN SPS beam line. Nuclei were tagged using HNX/TIGERISS silicon-strip detectors and silicon pad detectors, which allowed for fragmentation cuts in the data. The vastly saturating signals were reconstructed from the CsI:Na scintillation tail and show an APT charge resolution up to Z = 11 (with experimental limitations preventing full evaluation for Z larger 11) and demonstrated no significant non-linearity in the Z$^2$ measurement derived from the CsI:Na optical signal response up to $Z=82$.

We present a pipeline for fast GRB source localization for the Advanced Particle-astrophysics Telescope. APT records multiple Compton scatterings of incoming photons across 20 CsI detector layers, from which we infer the incident angle of each photon's first scattering to localize its source direction to a circle centered on the vector formed by its first two scatterings. Circles from multiple photons are then intersected to identify their common source direction. Our pipeline, which runs in real time on low-power hardware, uses an efficient tree search to determine the most likely ordering of scatterings for each photon (which cannot be measured due to the coarse time-scale of detection), followed by likelihood-weighted averaging and iterative least-squares refinement to combine all circles into an estimated source direction. Uncertainties in the scattering locations and energy deposits require that our pipeline be robust to high levels of noise. To test our methods, we reconstructed GRB events produced by a Geant4 simulation of APT's detectors paired with a second simulator that models measurement noise induced by the detector hardware. Our methods proved robust against noise and the effects of pair production, producing sub-degree localization for GRBs with fluence 0.3 MeV/cm^2. GRBs with fluence 0.03 MeV/cm^2 provided fewer photons for analysis but could still be localized within 2.5 degrees 68% of the time. Localization time for a 1-second 1.0 MeV/cm^2 GRB, measured on a quad-core, 1.4 GHz ARMv8 processor (Raspberry Pi 3B+), was consistently under 0.2 seconds — fast enough to permit real-time redirection of other instruments for follow-up observations.

We present simulations of the instrument performance of the Advanced Particle-astrophysics Telescope (APT), a mission concept of a $\gamma$-ray and cosmic-ray observatory in a sun-Earth Lagrange orbit. The key components of the APT detector include a multiple-layer tracker composed of scintillating fibers and an imaging calorimeter composed of thin layers of CsI:Na scintillators. The design is aimed at maximizing effective area and field of view for $\gamma$-ray and cosmic-ray measurements, subject to constraints on instrument cost and total payload mass. We simulate a detector design based on $3$-meter scintillating fibers and develop reconstruction algorithms for $\gamma$-rays from a few hundreds of $\mathrm{keV}$ up to a few $\mathrm{TeV}$ energies. At the photon energy above $30~\mathrm{MeV}$, pair-production/shower reconstruction is applied; the results show that APT could provide an order of magnitude improvement in effective area and sensitivity for $\gamma$-ray detection compared with the Fermi Large Area Telescope (LAT). A multiple-Compton-scattering reconstruction at photon energies below $10~\mathrm{MeV}$ achieves sensitive detection of faint $\gamma$-ray bursts (GRBs) and other $\gamma$-ray transients down to $\sim0.01~\mathrm{MeV/cm}^2$ with degree-level to sub-degree-level localization accuracy. The Compton analysis also provides a measurement of polarization where the minimum detectable degree of polarization for $\sim1~\mathrm{MeV/cm}^2$ GRBs is below $20\%$. In addition to the APT simulations, we present the simulated performance of the Antarctic Demonstrator for APT, a 0.5m-square cross section balloon experiment that includes all of the key elements of the full APT detector.

We describe the development of a future gamma-ray/cosmic-ray mission called the Advanced Particle-astrophysics Telescope (APT). The instrument will combine a pair tracker and Compton telescope in a single monolithic design. By using scintillating fibers for the tracker and wavelength-shifting fibers to readout CsI detectors, the instrument will achieve an order of magnitude improvement in sensitivity compared with Fermi but with fewer readout channels, and lower complexity. By incorporating multiple Compton imaging over a very large effective area, the instrument will also achieve orders of magnitude improvement in MeV sensitivity compared with other proposed instruments. The mission would have a broad impact on astroparticle physics; primary science drivers for the mission include: (1) probing WIMP dark matter across the entire natural mass range and annihilation cross section for a thermal WIMP, (2) providing a nearly all-sky instantaneous FoV, with prompt sub-degree localization and polarization measurements for gamma-rays transients such as neutron-star mergers and (3) making measurements of rare utra-heavy cosmic ray nuclei to distinguish between n-star merger and SNae r-process synthesis of the heavy elements. We will describe ongoing work including a series of accelerator beam tests, a piggy-back Antactic flight (APTlite) and the recently funded long-duration balloon mission: the Antarctic Demonstrator for APT (ADAPT).

The response to 150 GeV/nuc primary lead ($^{208}$Pb) and fragmented (A/Z=2.4, 2.2, 2.0) beams measured a silicon strip detector, designed for use in the Heavy Nuclei eXplorer (HNX) and an upgrade of the Super Trans-Iron Galactic Element Recorder (SuperTIGER) balloon experiment, was evaluated in a CERN test beam (H8A) during Nov - Dec 2018. The 500 $\mu$m thick, single-sided silicon detectors have 32 DC-coupled strips with 3 mm pitch on the junction side with $9.6 \times 9.6$ cm$^2$ active area. Discrete charge-preamplifiers and shaping amplifiers were used to read out the ohmic and junction side signals simultaneously using the SuperTIGER DAQ system. We report on the response in a configuration where all 32 strips were joined and read out together. The strip detector-under-test was situated between planar silicon detectors, which provided the charge selection as well as a comparison of the measured response of each detector. The combined data set shows excellent charge resolution and finely resolved elemental peaks from helium (Z=2) through lead (Z=82). In this paper, we provide a description of the test beam experiment and the results of the charge resolution analysis.

Silicon Photomultipliers (SiPM) are increasingly being used in ground-based astrophysics experiments as a replacement for Photomultiplier tubes (PMTs). These compact low power, rugged sensors are also well suited for space applications and have an added advantage over PMTs in that they do not require high-voltage bias. Efforts are underway at NASA Goddard and our collaborators to develop large-area arrays of SiPMs as the readout for the upcoming funded CubeSat missions such as BurstCube and Terrestrial RaYs Analysis and Detection (TRYAD) and also larger missions including the ultra-heavy cosmic-ray Heavy Nuclei Explorer (HNX) experiment and the gamma-ray Advanced Particle-astrophysics Telescope (APT) experiment. Our team has recently tested SiPMs in a heavy ion beam at CERN. The primary beam consisted of lead ions with energy of ~150 GeV/nuc. SiPM hardware was exposed to both a pure and fragmented Pb beam allowing us to look at ions from Z=1 to Z=82. We report in this paper on direct comparisons with the performance of Hamamatsu R1924A photomultipliers in addition to examining the signals (and subsequent effects) from direct exposure to a lead beam.

A frequency reference system is implemented with a BAW-based 2.52GHz oscillator, divider, temperature sensor, digital PLL, and final test at three temperatures to create a 48MHz reference frequency with +/−10ppm stability from −40 to 125°C. This reference clock periodically recalibrates a fully integrated 32kHz RC oscillator to less than +/−500ppm frequency variation so that it can be used as the wireless node sleep timer. The reference system enables a Bluetooth Low Energy compliant radio in 65nm CMOS to be realized without any crystals.

Thick polycrystalline gadolinium oxide (Gd 2 O 3 ) films up to 11 μm in thickness were deposited via reactive electron beam-physical vapor deposition (EB-PVD) on silicon (111) substrates for use in neutron radiation detection. The effects of coating thickness, substrate temperature, and oxygen flow on film structural, electrical and optical properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), capacitance–voltage (C–V) measurements, and ultraviolet–visible (UV–Vis) spectroscopy. Films were characterized as either monoclinic or mixed monoclinic and cubic phase depending on deposition parameters. Increasing the deposition temperature resulted in increased film crystallinity and cubic phase volume while decreasing the O 2 flow rate resulted in increased volume of the monoclinic phase. Evidence of a thickness dependent crystallography is also presented. Electrical property measurements showed thin film dielectric constant could be tailored between 12 and 20 at 1 MHz frequency by decreasing the oxygen flow rate at deposition temperatures of 250 °C which is attributed to an increased presence of the monoclinic phase and increased film density. Band gap values were calculated from transmission measurements and ranged between 5.44 and 5.96 eV.

Current state-of-the-art nanotechnology offers multiple benefits for radiation sensing applications. These include the ability to incorporate nano-sized radiation indicators into widely used materials such as paint, corrosion-resistant coatings, and ceramics to create nano-composite materials that can be widely used in everyday life. Additionally, nanotechnology may lead to the development of ultra-low power, flexible detection systems that can be embedded in clothing or other systems. Graphene, a single layer of graphite, exhibits exceptional electronic and structural properties, and is being investigated for high-frequency devices and sensors. Previous work indicates that graphene-oxide (GO) - a derivative of graphene - exhibits luminescent properties that can be tailored based on chemistry; however, exploration of graphene-oxide's ability to provide a sufficient change in luminescent properties when exposed to gamma or neutron radiation has not been carried out. We investigate the mechanisms of radiation-induced chemical modifications and radiation damage induced shifts in luminescence in graphene-oxide materials to provide a fundamental foundation for further development of radiation sensitive detection architectures. Additionally, we investigate the integration of hexagonal boron nitride (hBN) with graphene-based devices to evaluate radiation induced conductivity in nanoscale devices. Importantly, we demonstrate the sensitivity of graphene transport properties to the presence of alpha particles, and discuss the successful integration of hBN with large area graphene electrodes as a means to provide the foundation for large-area nanoscale radiation sensors.

We explore the effect of high-κ dielectric seed layer and overlayer on carrier transport in epitaxial graphene. We introduce a novel seeding technique for depositing dielectrics by atomic layer deposition that utilizes direct deposition of high-κ seed layers and can lead to an increase in Hall mobility up to 70% from as-grown. Additionally, high-κ seeded dielectrics are shown to produce superior transistor performance relative to low-κ seeded dielectrics and the presence of heterogeneous seed/overlayer structures is found to be detrimental to transistor performance, reducing effective mobility by 30-40%. The direct deposition of high-purity oxide seed represents the first robust method for the deposition of uniform atomic layer deposited dielectrics on epitaxial graphene that improves carrier transport.

We present the integration of epitaxial graphene with thin film dielectric materials for the purpose of graphene transistor development. The impact on epitaxial graphene structural and electronic properties following deposition of Al(2)O(3), HfO(2), TiO(2), and Ta(2)O(5) varies based on the choice of dielectric and deposition parameters. Each dielectric film requires the use of a nucleation layer to ensure uniform, continuous coverage on the graphene surface. Graphene quality degrades most severely following deposition of Ta(2)O(5), while the deposition if TiO(2) appears to improve the graphene carrier mobility. Finally, we discuss the potential of dielectric stack engineering for improved transistor performance.

A promising route for the synthesis of large-area graphene, suitable for standard device fabrication techniques, is the sublimation of silicon from silicon carbide at elevated temperatures (>1200 degrees C). Previous reports suggest that graphene nucleates along the (110n) plane, known as terrace step edges, on the silicon carbide surface. However, to date, a fundamental understanding of the nucleation of graphene on silicon carbide is lacking. We provide the first direct evidence that nucleation of epitaxial graphene on silicon carbide occurs along the (110n) plane and show that the nucleated graphene quality improves as the synthesis temperature is increased. Additionally, we find that graphene on the (110n) plane can be significantly thicker than its (0001) counterpart and appears not to have a thickness limit. Finally, we find that graphene along the (110n) plane can contain a high density of structural defects, often the result of the underlying substrate, which will undoubtedly degrade the electronic properties of the material. Addressing the presence of non-uniform graphene that may contain structural defects at terrace step edges will be key to the development of a large-scale graphene technology derived from silicon carbide.

The effects of growth temperature, film thickness, and oxygen flux on the microstructure, phase transition, and interfacial chemistry of gadolinium oxide (Gd2O3) films grown on Si(111) substrates by electron-beam physical vapor deposition were investigated using a combination of transmission electron microscopy (TEM), electron diffraction, scanning TEM, x-ray energy dispersive spectrometry, and electron energy loss spectrometry. The authors find that a low growth temperature (250 °C) and a high oxygen flux (200 sccm) led to a small grain size and a high porosity of the Gd2O3 film. Lowering the oxygen flux to 50 sccm led to reduced film porosity, presumably due to the increased diffusion length of the Gd atoms on the surface. Increasing the growth temperature to 650 °C resulted in a film with large columnar grains and elongated pores at the grain boundaries. Thin films grown at 250 °C consisted of cubic Gd2O3, but thermodynamically less stable monoclinic phase formed as the film thickness increased. Loweri...