1,777 research outputs found
Response of Ionospheric Electron Density to a Change of Electron Temperature
Get PDFSpatial and temporal models used to study response of ionospheric electron density to change of electron temperatur
Pivoting at the Midpoint: How Midpoint Course Adjustments Influence Student Engagement
Get PDFIn higher education, instructors must often pivot to new methods, approaches, and exercises to help students achieve learning objectives in a particular course. These course pivots can be challenging to navigate; however, they are often the difference between a successful course and an unsuccessful one. Research on the punctuated equilibrium model of group development provides important insights for instructors on managing and navigating course pivots. This article reviews research on midpoint transitions and discusses the benefits of implementing midpoint pivots. It then introduces an example of a midpoint course pivot: The Stop-Start-Continue exercise. It concludes with a discussion of the implications this exercise has for instructors and students alike
Plasma Diagnostics by Antenna Impedance Measurements
Get PDFThe impedance of an electrically short antenna immersed in a plasma provides an excellent in situ diagnostic tool for electron density and other plasma parameters. By electrically short we mean that the wavelength of the free-space electromagnetic wave that would be excited at the driving frequency is much longer than the physical size of the antenna. Probes using this impedance technique have had a long history with sounding rockets and satellites, stretching back to the early 1960s. This active technique could provide information on composition and temperature of plasmas for comet or planetary missions. Advantages of the impedance probe technique are discussed and two classes of instruments built and flown by SDL-USU for determining electron density (the capacitance and plasma frequency probes) are described
Trends and Issues in Educational Psychology
Get PDFThe review of issues in educational psychology looks at areas of innovation as well as areas of stagnation. The authors challenge researchers to find meaningful information which has utility in the development and improvement of teaching
Multicenter, randomized study to optimize bowel for colon capsule endoscopy
Get PDFAIM To assess the cleansing efficacy and safety of a new Colon capsule endoscopy (CCE) bowel preparation regimen. METHODS This was a multicenter, prospective, randomized, controlled study comparing two CCE regimens. Subjects were asymptomatic and average risk for colorectal cancer. The second generation CCE system (PillCam® COLON 2; Medtronic, Yoqneam, Israel) was utilized. Preparation regimens differed in the 1st and 2nd boosts with the Study regimen using oral sulfate solution (89 mL) with diatrizoate meglumine and diatrizoate sodium solution (“diatrizoate solution”) (boost 1 = 60 mL, boost 2 = 30 mL) and the Control regimen oral sulfate solution (89 mL) alone. The primary outcome was overall and segmental colon cleansing. Secondary outcomes included safety, polyp detection, colonic transit, CCE completion and capsule excretion = 12 h. RESULTS Both regimens had similar cleansing efficacy for the whole colon (Adequate: Study = 75.9%, Control = 77.3%; P = 0.88) and individual segments. In the Study group, CCE completion was superior (Study = 90.9%, Control = 76.9%; P = 0.048) and colonic transit was more often \u3c 40 min (Study = 21.8%, Control = 4%; P = 0.0073). More Study regimen subjects experienced adverse events (Study = 19.4%, Control = 3.4%; P = 0.0061), and this difference did not appear related to diatrizoate solution. Adverse events were primarily gastrointestinal in nature and no serious adverse events related either to the bowel preparation regimen or the capsule were observed. There was a trend toward higher polyp detection with the Study regimen, but this did not achieve statistical significance for any size category. Mean transit time through the entire gastrointestinal tract, from ingestion to excretion, was shorter with the Study regimen while mean colonic transit times were similar for both study groups. CONCLUSION A CCE bowel preparation regimen using oral sulfate solution and diatrizoate solution as a boost agent is effective, safe, and achieved superior CCE completion. © The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved
Molecular excitation in the Eagle nebula's fingers
Get PDFContext: The M16 nebula is a relatively nearby Hii region, powered by O stars
from the open cluster NGC 6611, which borders to a Giant Molecular Cloud.
Radiation from these hot stars has sculpted columns of dense obscuring material
on a few arcmin scales. The interface between these pillars and the hot ionised
medium provides a textbook example of a Photodissociation Region (PDR).
Aims: To constrain the physical conditions of the atomic and molecular
material with submillimeter spectroscopic observations.
Methods: We used the APEX submillimeter telescope to map a ~3'x3' region in
the CO J=3-2, 4-3 and 7-6 rotational lines, and a subregion in atomic carbon
lines. We also observed C18O(3-2) and CO(7-6) with longer integrations on five
peaks found in the CO(3-2) map. The large scale structure of the pillars is
derived from the molecular lines' emission distribution. We estimate the
magnitude of the velocity gradient at the tips of the pillars and use LVG
modelling to constrain their densities and temperatures. Excitation
temperatures and carbon column densities are derived from the atomic carbon
lines.
Results: The atomic carbon lines are optically thin and excitation
temperatures are of order 60 K to 100 K, well consistent with observations of
other Hii region-molecular cloud interfaces. We derive somewhat lower
temperatures from the CO line ratios, of order 40 K. The Ci/CO ratio is around
0.1 at the fingers tips.Comment: 4 pages, APEX A&A special issue, accepte
A candidate protostellar object in the L1457 / MBM12 cloud
Full text linkThe association of young T Tauri stars, MBM12A, indicates that L1457 was
forming stars not too long ago. With our study we want to find out whether or
not there are still signs for ongoing star formation in that cloud. Using the
Max-Planck-Millimeter-Bolometer MAMBO at the IRAM 30m telescope we obtained a
map of about 8' by 8' centered on L1457 in the dust continuum emission at 230
GHz. Towards the most intense regions in our bolometer map we obtained spectra
at high angular resolution in the CS (2-1) and the N2H+(1-0) lines using the
IRAM 30m telescope. We find that the cold dust in L1457 is concentrated in
several small cores with high H2 column densities and solar masses. The density
profiles of the cores are inconsistent with a sphere with constant density.
These cores are closer to virial equilibrium than the cloud as a whole. Data
from the VLA and Spitzer archives reveal two point sources in the direction of
one dust core. One of the sources is probably a distant quasar, whereas the
other source is projected right on a local maximum of our dust map and shows
characteristics of a protostellar object.Comment: 4 pages, 4 figures, accepted by Astronomy & Astrophysic
A Resolved Ring of Debris Dust around the Solar Analog HD 107146
Get PDFWe present resolved images of the dust continuum emission from the debris disk around the young (80-200 Myr) solar-type star HD 107146 with CARMA at λ = 1.3 mm and the CSO at λ = 350 μ. Both images show that the dust emission extends over an approximately 10" diameter region. The high-resolution (3") CARMA image further reveals that the dust is distributed in a partial ring with significant decrease in a flux inward of 97 AU. Two prominent emission peaks appear within the ring separated by ~140° in the position angle. The morphology of the dust emission is suggestive of dust captured into a mean motion resonance, which would imply the presence of a planet at an orbital radius of ~45-75 AU
How do women feel cold water swimming affects their menstrual and perimenopausal symptoms?
Get PDFOBJECTIVE: This study aimed to determine how women felt cold water swimming affected their menstrual and perimenopausal symptoms. STUDY DESIGN: An online survey that asked women who regularly swim in cold water about their experiences. The survey was advertised for 2 months on social media. Questions related to cold water swimming habits and menstrual and perimenopausal symptoms were analysed. MAIN OUTCOME MEASURES: Quantitative and qualitative data including; frequency of menstrual and menopause symptoms, the effect of cold water swimming on these symptoms. RESULTS: 1114 women completed the survey. Women reported that cold water swimming reduced their menstrual symptoms, notably psychological symptoms such as anxiety (46.7%), mood swings (37.7%) and irritability (37.6%). Perimenopausal women reported a significant improvement in anxiety (46.9%), mood swings (34.5%), low mood (31.1%) and hot flushes (30.3%). The majority of women with symptoms swam specifically to reduce these symptoms (56.4% for period and 63.3% for perimenopause symptoms). Women said they felt it was the physical and mental effects of the cold water that helped their symptoms. For the free text question, five themes were identified: the calming and mood-boosting effect of the water, companionship and community, period improvements, an improvement in hot flushes and an overall health improvement. CONCLUSION: Women felt that cold water swimming had a positive overall effect on menstrual and perimenopause symptoms. Studies on other forms of exercise to relieve menstrual and perimenopause symptoms may show similar findings
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