1,492 research outputs found
Introduction
The Department of Obstetrics and Gynecology welcomed the opportunity to present the 51st Annual McGuire Lecture Series. The lectures were designed to provide the primary care physician with information which is clinically useful and applicable to the daily practice of obstetrics and gynecology. An effort was made to achieve a balance between those health problems that have been known for some time but whose understanding has changed and those problems that have been recognized more recently and whose solutions are still evolving
Cervical Cytology and Colposcopy
Colposcopy was first described by Hinselmann of Hamburg in 1925. The colposcope is a binocular microscope of low power (10x to 25x) which contains a light source and is mounted on a stand to permit its use in the study of the surface of the uterine cervix. Using the colposcope, the physician can identify and evaluate cervical epithelial abnormalities
Endometriosis
Endometriosis is diagnosed when tissue which resembles the endometrial lining exists outside the endometrial cavity. Although first described as a pathological entity in the late 1800s, the term “endometriosis” was not introduced until the early 1920s by Sampson. The great volume of literature which has accumulated on this topic is, by and large, a product of the 20th century
Office Endometrial Sampling
The concept of office endometrial sampling is not new. Kelly recommended its use in 1925. More recently, the procedure has received increased attention as physicians and the public have sought ways to curb the spiraling cost of medical care. Uterine curettage is the operation most commonly performed on women throughout the world. As an inpatient procedure, it costs 600. The same procedure performed in an outpatient surgical center costs 400. In over 90% of cases, an adequate endometrial sample may be obtained in the office at a cost of 60. For office endometrial sampling to be acceptable to the physician, it must be simple to accomplish, relatively inexpensive to use, and agreeable in terms of patient comfort and morbidity. The specimen obtained should be representative of the entire endometrium, adequate for pathological study, and easily preserved, transported, and processed
UV Imaging Polarimetry of the peculiar Seyfert 2 galaxy Mrk 477
We present the results of UV imaging polarimetry of the Seyfert 2 galaxy Mrk
477 taken by the Faint Object Camera onboard the Hubble Space Telescope (HST).
From a previous HST UV image (lambda ~ 2180A), Mrk 477 has been known to have
a pointlike bright UV hotspot in the central region, peculiar among nearby
Seyfert 2 galaxies. There are also claims of UV/optical variability, unusual
for a Seyfert 2 galaxy. Our data show that there is an off-nuclear scattering
region ~ 0."6 (~ 500 pc) NE from the hotspot. The data, after the subtraction
of the instrumental effect due to this bright hotspot region, might indicate
that the scattered light is also detected in the central 0."2 radius region and
is extended to a very wide angle. The hotspot location is consistent with the
symmetry center of the PA pattern, which represents the location of the hidden
nucleus, but our data do not provide a strong upper limit to the distance
between the symmetry center and the hotspot. We have obtained high spatial
resolution color map of the continuum which shows that the nuclear spiral arm
of 0."4 scale (~ 300pc) is significantly bluer than the off-nuclear mirror and
the hotspot region. The nature of the hotspot is briefly discussed.Comment: To appear in Ap
Implementing Digital Tools to Support Student Questioning Abilities: A Collaborative Action Research Report
This collaborative action research project was conducted in a second-grade classroom to determine the impact that digital web-based tools would have in helping a school media coordinator scaffold her students’ understanding of productive versus non-productive questions. The digital tools Kahoot, Quizizz, and Socrative were used by the students to help them recognize the difference between productive and non-productive questions, as well as supporting them in the ability to generate their own productive questions. While results related to student learning outcomes showed minimal increases, the researchers found that the iterative and reflective nature of the action research cycle enabled the media coordinator and researcher to refine their original choices of digital technology based on formative assessment in the action research cycle to select the digital tools that best fit the context of this specific learning environment. These findings offer further support for the use of collaborative action research as a means to assist educators in choosing the right digital tools to meet their students’ learning needs
A Hardy inequality in twisted waveguides
We show that twisting of an infinite straight three-dimensional tube with
non-circular cross-section gives rise to a Hardy-type inequality for the
associated Dirichlet Laplacian. As an application we prove certain stability of
the spectrum of the Dirichlet Laplacian in locally and mildly bent tubes.
Namely, it is known that any local bending, no matter how small, generates
eigenvalues below the essential spectrum of the Laplacian in the tubes with
arbitrary cross-sections rotated along a reference curve in an appropriate way.
In the present paper we show that for any other rotation some critical strength
of the bending is needed in order to induce a non-empty discrete spectrum.Comment: LaTeX, 20 page
UV Imaging Polarimetry of the Seyfert 2 Galaxy Mrk 3
We present UV imaging polarimetry data of the Seyfert 2 galaxy Mrk 3 taken by
the Hubble Space Telescope. The polarized flux is found to be extended to ~1
kpc from the nucleus, and the position angles of polarization are
centrosymmetric, confirming that the polarization is caused by scattering. We
determine the location of the hidden nucleus as the center of this
centrosymmetric pattern. From the polarization images taken in two broad bands,
we have obtained the color distribution of the polarized flux. Some regions
have blue polarized flux, consistent with optically-thin dust scattering, but
some bright knots have a color similar to that of Seyfert 1 nucleus. Also, the
recent Chandra X-ray observation suggests that the ratio of scattered UV flux
to scattered X-ray flux is rather similar to the intrinsic UV/X-ray ratio in a
Seyfert 1 nucleus, if the observed extended X-ray continuum is scattered light.
While the scattered X-ray would be essentially from electron scattering, the UV
slope and UV/X-ray ratio both being similar to Seyfert 1's would lead to two
possibilities as to the nature of the UV scatterers. One is that the UV may
also be scattered by electrons, in which case the scattering gas is somehow
dust-free. The other is that the UV is scattered by dust grains, but the
wavelength-independent UV scattering with low efficiency indicated by the UV
slope and UV/X-ray ratio would suggest that the grains reside in UV-opaque
clouds, or the dust might be mainly composed of large grains and lacks
small-grain population.Comment: 15 pages, 8 figures (plus 2 color versions of grayscale figures), To
appear in ApJ; minor corrections for the proofs of the manuscrip
Release of antimicrobial compounds from a zinc oxide-chelate cement
This study examined the release of cetylpyridinium chloride and benzalkonium chloride from fatty acid chelate temporary dental cement and their antimicrobial effects. The cement was Cavex Temporary, and either cetylpyridinium chloride or benzalkonium chloride was added (1% or 5% by mass), incorporating into the base paste. Release of the additives was determined by reverse-phase high-performance liquid chromatography. Possible chemical interactions between the cement components and additives were examined by Fourier transform infrared (FTIR) spectroscopy. Antimicrobial effects were assessed by measuring the zone of inhibition around sample discs after 24 h in a Streptococcus mutans culture. FTIR spectroscopy showed no interaction with cement components. For both additives, release was by diffusion for approximately the first 6 hours, with equilibration after about 2 weeks. Diffusion coefficients were 1.76 m2 s½ to 8.05 × 10−12 m2 s½ and total release was 10.3 to 44.7% of additive loading. Zones of inhibition with additive were significantly larger than those for control discs. In conclusion, the antimicrobial properties of Cavex temporary cement are improved by the addition of the antimicrobial compounds cetylpyridium chloride and benzalkonium chloride, which are released by a diffusion process
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