1,144 research outputs found
Improved head-controlled TV system produces high-quality remote image
Manipulator operator uses an improved resolution tv camera/monitor positioning system to view the remote handling and processing of reactive, flammable, explosive, or contaminated materials. The pan and tilt motions of the camera and monitor are slaved to follow the corresponding motions of the operators head
Improved electromechanical master-slave manipulator
Electric master-slave manipulator uses force multiplication and allows the operator to remotely control the slave arm. Both the master and slave arms execute seven distinct motions by a specially designed force-reflecting servo having a one to one correspondence between the motion at the master and slave
Radial diffusion in Jupiter's magnetosphere
Radial phase space density profiles for equatorially mirroring particles are computed from the data of the University of Iowa packages on Pioneer 10. The profiles are only consistent with radial diffusion subject to nonadiabatic losses. It is suggested that these losses are due to pitch angle scattering by whistler turbulence
High resolution measurements of density structures in the Jovian plasma sheet
A recent effort to digitize the plasma density by using the low frequency cutoff of trapped continuum radiation in the vicinity of the Jovian plasma sheet has revealed the existence of sharply defined density structures in the plasma sheet. These structures typically have a plasma density which is relatively constant but of order 50 percent greater or less than in the surrounding plasma. At the boundaries of these structures, the transitions from low to high density occur on time scales of about ten seconds, which correspond to spatial dimensions on the order of a few ion Larmor radii. The structures themselves last for intervals from less than a minute to more than five minutes, corresponding to size scales from a fraction of a Jovian radius to more than a Jovian radius, depending of the velocity of the structure relative to the spacecraft. In view of the importance of near corotation plasma flows, these structures are likely to be limited in both the longitudinal and radial dimensions and, therefore, could represent flux tubes with greatly varying plasma content. These observations are presented as among the first to directly address the theoretically proposed interchange instability
Effects of chemical releases by the STS-3 Orbiter on the ionosphere
The Plasma Diagnostics Package, flown aboard STS-3 as part of the first Shuttle payload (OSS-1), recorded the effects of various chemical releases from the Orbiter. Changes in the plasma environment was observed during flash evaporator system releases, water dumps and maneuvering thruster operations. During flash evaporator operations, broadband Orbiter-generated electrostatic noise was enhanced and plasma density irregularities were observed to increase by 3 to 30 times with a spectrum which rose steeply and peaked below 6 Hz. In the case of water dumps, background electrostatic noise was enhanced at frequencies below about 3 kHz and suppressed at frequencies above 2 kHz. Thruster activity also stimulated electrostatic noise with a spectrum which peaked at approximately 0.5 kHz. In addition, ions with energies up to 1 keV were seen during some thruster events
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Beyond spinal manipulation: should Medicare expand coverage for chiropractic services? A review and commentary on the challenges for policy makers
Objectives: Private insurance plans typically reimburse doctors of chiropractic for a range of clinical services, but Medicare reimbursements are restricted to spinal manipulation procedures. Medicare pays for evaluations performed by medical and osteopathic physicians, nurse practitioners, physician assistants, podiatrists, physical therapists, and occupational therapists; however, it does not reimburse the same services provided by chiropractic physicians. Advocates for expanded coverage of chiropractic services under Medicare cite clinical effectiveness and patient satisfaction, whereas critics point to unnecessary services, inadequate clinical documentation, and projected cost increases. To further inform this debate, the purpose of this commentary is to address the following questions: (1) What are the barriers to expand coverage for chiropractic services? (2) What could potentially be done to address these issues? (3) Is there a rationale for Centers for Medicare and Medicaid Services to expand coverage for chiropractic services? Methods: A literature search was conducted of Google and PubMed for peer-reviewed articles and US government reports relevant to the provision of chiropractic care under Medicare. We reviewed relevant articles and reports to identify key issues concerning the expansion of coverage for chiropractic under Medicare, including identification of barriers and rationale for expanded coverage. Results: The literature search yielded 29 peer-reviewed articles and 7 federal government reports. Our review of these documents revealed 3 key barriers to full coverage of chiropractic services under Medicare: inadequate documentation of chiropractic claims, possible provision of unnecessary preventive care services, and the uncertain costs of expanded coverage. Our recommendations to address these barriers include the following: individual chiropractic physicians, as well as state and national chiropractic organizations, should continue to strengthen efforts to improve claims and documentation practices; and additional rigorous efficacy/effectiveness research and clinical studies for chiropractic services need to be performed. Research of chiropractic services should target the triple aim of high-quality care, affordability, and improved health. Conclusions: The barriers that were identified in this study can be addressed. To overcome these barriers, the chiropractic profession and individual physicians must assume responsibility for correcting deficiencies in compliance and documentation; further research needs to be done to evaluate chiropractic services; and effectiveness of extended episodes of preventive chiropractic care should be rigorously evaluated. Centers for Medicare and Medicaid Services policies related to chiropractic reimbursement should be reexamined using the same standards applicable to other health care providers. The integration of chiropractic physicians as fully engaged Medicare providers has the potential to enhance the capacity of the Medicare workforce to care for the growing population. We recommend that Medicare policy makers consider limited expansion of Medicare coverage to include, at a minimum, reimbursement for evaluation and management services by chiropractic physicians
4,6-Bis(diphenylphosphanyl)-2,8-dimethylphenoxathiin dichloromethane monosolvate
The title compound, C38H30OP2S·CH2Cl2, belongs to the xanthene family of ligands containing S- and O-donor atoms in the central heterocylic ring. Positions 2 and 8 on the xanthene backbone are functionalized with methyl groups to allow for the selective functionalization of the backbone at positions 4 and 6 with diphenylphosphanyl units. The title compound shows a significant ‘roof-like’ bending along the axis of planarity involving the O- and S-donor atoms and the benzene rings, resulting in a dihedral angle between the mean planes of the benzene rings of 32.88 (13)°
The Jefferson Lab Frozen Spin Target
A frozen spin polarized target, constructed at Jefferson Lab for use inside a
large acceptance spectrometer, is described. The target has been utilized for
photoproduction measurements with polarized tagged photons of both longitudinal
and circular polarization. Protons in TEMPO-doped butanol were dynamically
polarized to approximately 90% outside the spectrometer at 5 T and 200--300 mK.
Photoproduction data were acquired with the target inside the spectrometer at a
frozen-spin temperature of approximately 30 mK with the polarization maintained
by a thin, superconducting coil installed inside the target cryostat. A 0.56 T
solenoid was used for longitudinal target polarization and a 0.50 T dipole for
transverse polarization. Spin-lattice relaxation times as high as 4000 hours
were observed. We also report polarization results for deuterated propanediol
doped with the trityl radical OX063.Comment: 11 pages, 12 figures, preprint submitted to Nuclear Instruments and
Methods in Physics Research, Section
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