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A Rare Case of Hip Pain Secondary to Pigmented Villonodular Synovitis
A 19-year-old Asian male presented to our emergency department with atraumatic right hip pain radiating to the right groin associated with pain on ambulation. Magnetic resonance imaging of the right hip with and without contrast revealed the diagnosis. Pigmented villonodular synovitis is a rare, monoarticular benign tumor originating from the synovium of the joint. The treatment is synovectomy of the pathological joint to prevent further disease progression
125 - 211 GHz low noise MMIC amplifier design for radio astronomy
To achieve the low noise and wide bandwidth required for millimeter wavelength astronomy applications, superconductor-insulator-superconductor (SIS) mixer based receiver systems have typically been used. This paper investigates the performance of high electron mobility transistor (HEMT) based low noise amplifiers (LNAs) as an alternative approach for systems operating in the 125 — 211 GHz frequency range. A four-stage, common-source, unconditionally stable monolithic microwave integrated circuit (MMIC) design is presented using the state-of-the-art 35 nm indium phosphide HEMT process from Northrop Grumman Corporation. The simulated MMIC achieves noise temperature (T_e) lower than 58 K across the operational bandwidth, with average T_e of 38.8 K (corresponding to less than 5 times the quantum limit (hf/k) at 170 GHz) and forward transmission of 20.5 ± 0.85 dB. Input and output reflection coefficients are better than -6 and -12 dB, respectively, across the desired bandwidth. To the authors knowledge, no LNA currently operates across the entirety of this frequency range. Successful fabrication and implementation of this LNA would challenge the dominance SIS mixers have on sub-THz receivers
Opportunities for Small Satellites and Space Research using the K-1 Vehicle
Kistler Aerospace Corporation will launch the K-I vehicle into orbit from Spaceport Woomera for its first flight test in 2000 and commence commercial operations shortly thereafter. These events will mark two important milestones in aerospace history. First, the K-I is the world\u27s first fully reusable aerospace vehicle, designed for 100 flights. Second, the K-I is the first launch vehicle built entirely by private funds for the commercial launch market. Expendable vehicle launch costs make up a significant portion of satellite program budgets. These costs can be prohibitive for small satellites and space researchers. The reusable K-l vehicle provides a low cost alternative for access to low-earth orbit (LEO). While large commercial LEO satellites form the core of the K-l\u27s target market, the K-I can also deliver small satellites as either secondary or primary payloads. The K-l can also be considered as a platform for microgravity experiments. Meeting several integration challenges is the key to realizing the potential of the K-l to support the small satellite and space research communities. These challenges include minimizing the non-recurring engineering required for integration of structures and electrical systems, matching orbits for two or more spacecraft, resolving mutual environment interactions, and solving contractual and scheduling issues. Kistler is committed to working towards viable approaches to make the K-I\u27s low cost space access capability available to the small satellite and space research communities
Molecular Dynamics Simulation of the ENTH Domain on Lipid Bilayer
This research study compares the effect of polypropylene and wool fibers on the mechanical properties of natural polymer based stabilized soils. Biocomposites are becoming increasingly prevalent and this growth is expected to continue within a number of sectors including building materials. The aim of this study was to investigate the influence of different fiber reinforced natural polymer stabilized soils with regards to mechanical properties and fiber adhesion characteristics. The polymer includes alginate, which is used in a wide range of applications but has not been commonly used within engineering and construction applications. In recent years, natural fibers have started to be used as an ecological friendly alternative for soil reinforcement within a variety of construction applications. Test results in this study have compared the effects of adding natural and synthetic fibers to clay soils and discussed the importance of an optimum soil specification. A correlation between the micro structural analysis using scanning electron microscope (SEM), fiber typology, fiber–matrix bonds and the mechanical properties of the stabilized soils is also discussed
An Efficient Approach to Correspondences between Multiple Non-Rigid Parts
Identifying multiple deformable parts on meshes and establishing dense correspondences between them are tasks
of fundamental importance to computer graphics, with applications to e.g. geometric edit propagation and texture
transfer. Much research has considered establishing correspondences between non-rigid surfaces, but little
work can both identify similar multiple deformable parts and handle partial shape correspondences. This paper
addresses two related problems, treating them as a whole: (i) identifying similar deformable parts on a mesh,
related by a non-rigid transformation to a given query part, and (ii) establishing dense point correspondences
automatically between such parts. We show that simple and efficient techniques can be developed if we make the
assumption that these parts locally undergo isometric deformation. Our insight is that similar deformable parts
are suggested by large clusters of point correspondences that are isometrically consistent. Once such parts are
identified, dense point correspondences can be obtained by an iterative propagation process. Our techniques are
applicable to models with arbitrary topology. Various examples demonstrate the effectiveness of our techniques
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