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Core collapse supernovae are thought to be one of the main sources in the galaxy of elements heavier than iron. Understanding the origin of the elements is thus tightly linked to our understanding of the explosion mechanism of supernovae and supernova nucleosynthesis. X-ray and gamma-ray observations of young supernova remnants, combined with improved theoretical modeling, have resulted in enormous improvements in our knowledge of these events. The isotope ${}^{44}$Ti is one of the most sensitive probes of the innermost regions of the core collapse engine, and its spatial and velocity distribution are key observables. Hard X-ray imaging spectroscopy with the Nuclear Spectroscopic Telescope Array (NuSTAR) has provided new insights into the structure of the supernova remnant Cassiopeia A (Cas A), establishing the convective nature of the supernova engine. However, many questions about the details of this engine remain. We present here the concept for a balloon-borne follow-up mission called ASCENT (A SuperConducting ENergetic x-ray Telescope). ASCENT uses transition edge sensor gamma-ray microcalorimeter detectors with a demonstrated 55 eV Full Width Half Maximum (FWHM) energy resolution at 97 keV. This 8--16-fold improvement in energy resolution over NuSTAR will allow high resolution imaging and spectroscopy of the ${}^{44}$Ti emission. This will allow a detailed reconstruction of gamma-ray line redshifts, widths, and shapes, allowing us to address questions such as: What is the source of the neutron star "kicks"? What is the dominant production pathway for ${}^{44}$Ti? Is the engine of Cas A unique?, Comment: 23 pages, 11 figures

The Line Emission Mapper (LEM) is an X-ray Probe for the 2030s that will answer the outstanding questions of the Universe's structure formation. It will also provide transformative new observing capabilities for every area of astrophysics, and to heliophysics and planetary physics as well. LEM's main goal is a comprehensive look at the physics of galaxy formation, including stellar and black-hole feedback and flows of baryonic matter into and out of galaxies. These processes are best studied in X-rays, and emission-line mapping is the pressing need in this area. LEM will use a large microcalorimeter array/IFU, covering a 30x30' field with 10" angular resolution, to map the soft X-ray line emission from objects that constitute galactic ecosystems. These include supernova remnants, star-forming regions, superbubbles, galactic outflows (such as the Fermi/eROSITA bubbles in the Milky Way and their analogs in other galaxies), the Circumgalactic Medium in the Milky Way and other galaxies, and the Intergalactic Medium at the outskirts and beyond the confines of galaxies and clusters. LEM's 1-2 eV spectral resolution in the 0.2-2 keV band will make it possible to disentangle the faintest emission lines in those objects from the bright Milky Way foreground, providing groundbreaking measurements of the physics of these plasmas, from temperatures, densities, chemical composition to gas dynamics. While LEM's main focus is on galaxy formation, it will provide transformative capability for all classes of astrophysical objects, from the Earth's magnetosphere, planets and comets to the interstellar medium and X-ray binaries in nearby galaxies, AGN, and cooling gas in galaxy clusters. In addition to pointed observations, LEM will perform a shallow all-sky survey that will dramatically expand the discovery space., 18 pages. White paper for a mission concept to be submitted for the 2023 NASA Astrophysics Probes opportunity. v2: All-sky survey figure expanded, references fixed. v3: Added energy resolution measurements for prototype detector array. v4: Author list and reference fixes

We report measurements of the 103-keV and 159-keV gamma ray signatures of 242Pu using microcalorimetry. This is the first observation of these gamma rays in a non-destructive measurement of an unprepared sample, and so represents an important advance in nuclear material accountancy. The measurement campaign also serves as the first demonstration of a field campaign with a portable microcalorimeter gamma-ray spectrometer. For the 103-keV gamma ray we report an improved centroid energy and emission probability., 6 pages, 7 figures

X-ray nanotomography has proven to be a powerful tool for the characterization of nanoscale materials and structures, such as energy storage devices and next-generation integrated circuits (ICs). In a nanotomography measurement the X-ray spot size must be kept at the nanoscale, which significantly limits the total amount of X-ray flux achievable. Due to this photon limit, nanotomography has been generally restricted to synchrotron facilities, where higher flux can be maintained even at nanoscale spot sizes. Here, we present a laboratory-scale nanotomography instrument, deemed TOMCAT (TOMographic Circuit Analysis Tool). TOMCAT combines the electron beam of a scanning electron microscope (SEM) with the precise, broadband X-ray detection of a superconducting transition-edge sensor (TES) spectrometer. The electron beam generates a highly focused X-ray spot in a metal target, while the TES spectrometer isolates target photons with high signal-to-noise. TOMCAT design is discussed, including target optimization, system geometry, and scan procedures. Features which are 160 nm wide are resolved in three-dimensional images on a Cu-SiO$_2$ IC sample, demonstrating the capabilities of laboratory-scale nanotomography based on a focused electron beam and TES spectrometer., Comment: The following article has been submitted to Review of Scientific Instruments

With the high resolution of microcalorimeter detectors, previously unresolvable gamma-ray lines are now clearly resolvable. A careful measurement of 241Am decay with a large microcalorimeter array has yielded never before seen or predicted gamma lines at 207.72 +/- 0.02 keV and 208.21 +/- 0.01 keV. These have been made possible because of new microwave-multiplexing readout and improved analysis algorithms for microcalorimeters., Comment: 5 pages, 3 figures, 2 tables

The absolute neutrino mass is still a missing parameter in the modern landscape of particle physics.The HOLMES experiment aims to perform a direct measurement of the neutrino mass with a sensitivity of the order of 2 eV. The neutrino mass will be studied through the calorimetric measurement of the decay products of the weak process decay of 163 Ho. To achieve the target sensitivity, HOLMES will combine the use of 1000 low temperature TES microcalorimeters with the use of a sophisticated software, designed for the signal processing and data analysis. The detector and readout technology will be pushed to their limits in order to preserve the detectors performance and the high multiplexing factor at the same time. This contribution will provide an overview on the status of the major tasks that will bring HOLMES to life: from the isotope production and embedding to the detector production and readout.

Transition-Edge Sensors (TESs) are two-dimensional superconducting films used to detect energy or power. TESs are voltage biased in the resistive transition where the film resistance is both finite and a strong function of temperature. Electrical noise is observed in TESs that exceeds the predictions of existing noise theories. In this manuscript, we describe a model for the unexplained excess noise based on the dynamic resistance of the TES and noise mixed down from frequencies around the Josephson oscillations. We derive an expression for the power spectral density of this noise and show that its predictions match measured data.

Since 1970, the HELP hospital information system has been collecting data into a common integrated database at the LDS Hospital. With the vast amount of stored information, there is a critical need for data extraction tools to use and verify these collected data. The purpose of this thesis in to increase and improve the access to the HELP patient database so that physicians can utilize the wealth of stored information, in establishing new medical standards or verifying existing ones. In order to increase the access to the patient database an information retrieval system will be created to acquire the data stored on the LDS Hospital TANDEM computer system and allow the transfer of that data to a variety of personal computers. To improve access to the patient database, a new query interface of editor will generate and execute PAL (PTXT APPLICATION LANGUAGE) queries to extract information from the database.

Objective: To evaluate relationships between Anterior Tibial Shear Force (ATSF) and eccentric quadriceps strength (QuadEcc), concentric hamstring strength (HamCon), and the QuadEcc/HamCon ratio. Design: Correlational. Setting: Research laboratory. Participants: Thirty-three healthy female recreational athletes. Main Outcome Measure(s): ATSF was measured during a landing task via inverse dynamics. QuadEcc and HamCon were assessed at 60°/s, 180°/s, and 300°/s using isokinetic dynamometry. Results: QuadEcc and HamCon were not significantly related to ATSF at any testing velocity (p > 0.05). QuadEcc/HamCon was significantly related to ATSF at 60°/s (r = 0.529, p = 0.005) and 180°/s (r = 0.556, p = 0.003). Conclusion: QuadEcc and HamCon in isolation are not significantly related to ATSF. However, when considered as a functional ratio, these strength measures are predictors of ATSF. This suggests that high QuadEcc/HamCon ratios may predispose female athletes to higher ATSF and ACL injury risk. Key Words: knee injury, ACL, torque, strength ratios

2020 Visions, Transforming Education and Training through Advanced Technologies, The Last Teacher: Michael Zyda, Director, The MOVES Institute, Naval Postgraduate School, and Douglas H. Bennett, Study Director, National Research Council’s Aeronautics and Space Engineering Board Technology that enables a revolution is always accompanied by upheaval of some form or another. The experience of change is part of being human and is not necessarily bad. However, if not thought out carefully, there can be manifold unintended consequences that fall out from advances in technology, be it revolutionary or not. With funding and motivation, the following is possible in 15 to 20 years. But what is possible should be thought about very carefully.

The Forest Engineering Research Institute of Canada (FERIC) worked with International Forest Products Limited (INTERFOR) to plan and implement a partial cutting trial at Chamiss Bay on Vancouver Island's west coast. A study was conducted to investigate the harvesting feasibility of partial cutting in old-growth stands on steep slopes. The study sites were located within the CWHvml biogeoclimatic unit. Harvesting, using manual falling and cable yarding systems, was done in the summers of 1995 and 1996. Two partial cuts (referred to as retention units), two strip cuts, and one clearcut were included in the harvesting study. The retention units had high levels of tree retention, 65 and 70% by basal area, with uniform dispersal of the retained trees. Harvesting productivities and costs were derived from shift-level production reports. Post-harvest surveys were conducted to quantify residual stand damage and soil disturbance levels in the retention units. In the 65% retention unit, falling productivity was 31% lower and unit falling cost was 45% higher than in the clearcut. However, falling productivity was reduced by only 1.6% in the 70% retention unit, compared to the clearcut, mainly because of a marked difference in timber type between this unit and the clearcut. Cable yarding productivity, measured in m 3 (volume of logs) per productive machine hour (m3/PMH), was 34 and 30% lower in the 65 and 70% retention units, respectively, than in the clearcut. Unit yarding costs, based on scheduled machine hours (SMH), were 46 and 32% higher in these same units. These are the relative differences in yarding productivity and cost for the Chamiss Bay trial where a clearcut in similar steep terrain, with no landings, was used for comparison. Post-harvest surveys showed that 33.5 and 37.3% of the residual stems had at least one scar of any size, and 11.7 and 9.7% of the residual stems had at least one scar that was 900 cm2 or greater, in the 65 and 70% retention units, respectively. Exposed mineral soil was observed on only 1.4 and 1.5% of the soil surface area in the 65 and 70% retention units, respectively. The productivity and cost results for the retention units provide important new information to help forest operators plan, budget and implement future partial cutting trials. The trial showed the potential to harvest timber on sensitive sites, with conventional equipment and crews, thus creating an opportunity to augment timber supplies.

no abstract provided by author Bachelor of Science

The 511 keV gamma-ray emission from the galactic center region may fully or partially originate from the annihilation of positrons from dark matter particles with electrons from the interstellar medium. Alternatively, the positrons could be created by astrophysical sources, involving exclusively standard model physics. We describe here a new concept for a 511 keV mission called 511-CAM (511 keV gamma-ray CAmera using Micro-calorimeters) that combines focusing gamma-ray optics with a stack of Transition Edge Sensor (TES) microcalorimeter arrays in the focal plane. The 511-CAM detector assembly has a projected 511 keV energy resolution of 390 eV Full Width Half Maximum (FWHM) or better, and improves by a factor of at least 11 on the performance of state-of-the-art Ge-based Compton telescopes. Combining this unprecedented energy resolution with sub-arcmin angular resolutions afforded by Laue lens or channeling optics could make substantial contributions to identifying the origin of the 511 keV emission by discovering and characterizing point sources and measuring line-of-sight velocities of the emitting plasmas., 19 pages, 12 figures, 2 tables

An examination of a report published by the Psychiatric Rehabilitation Association.