1,442 research outputs found
Perceived Racial Discrimination and Nonadherence to Screening Mammography
Objective. We examined whether African American women were as likely as White women to receive the results of a recent mammogram and to self-report results that matched the mammography radiology report (i.e., were adequately communicated). We also sought to determine whether the adequacy of communication was the same for normal and abnormal results. Methods. From a prospective cohort study of mammography screening, we compared self-reported mammogram results, which were collected by telephone interview, to results listed in the radiology record of 411 African American and 734 White women who underwent screening in 5 hospital-based facilities in Connecticut between October 1996 and January 1998. Using multivariate logistic regression, we identified independent predictors of inadequate communication of mammography results. Results. It was significantly more common for African American women to experience inadequate communication of screening mammography results compared with White women, after adjustment for sociodemographic, access-to-care, biomedical, and psychosocial factors. Abnormal mammogram results resulted in inadequate communication for African American women but not White women (PAfrican American women may not be receiving the full benefit of screening mammograms because of inadequate communication of results, particularly when mammography results are abnormal
Neighborhood and Individual Level Socioeconomic Variation in Perceptions of Racial Discrimination
In approaching the study of racial discrimination and health, the neighborhood and individual-level antecedents of perceived discrimination need further exploration. We investigated the relationship between neighborhood and individual-level socioeconomic position (SEP), neighborhood racial composition, and perceived racial discrimination in a cohort of African-American and White women age 40-79 from Connecticut, USA.
Design. The logistic regression analysis included 1249 women (39% African- American and 61% White). Neighborhood-level SEP and racial composition were determined using 1990 census tract information. Individual-level SEP indicators included income, education, and occupation. Perceived racial discrimination was measured as lifetime experience in seven situations.
Results. For African-American women, living in the most disadvantaged neighborhoods was associated with fewer reports of racial discrimination (odds ratio (OR) 0.44; 95% confidence interval (CI) 0.26, 0.75), with results attenuated after adjustment for individual-level SEP (OR 0.54, CI: 0.29, 1.03), and additional adjustment for neighborhood racial composition (OR 0.70, CI: 0.30, 1.63). African-American women with 12 years of education or less were less likely to report racial discrimination, compared with women with more than 12 years of education (OR 0.57, CI: 0.33, 0.98 (12 years); OR 0.51, CI: 0.26, 0.99 (less than 12 years)) in the fully adjusted model. For White women, neither neighborhood-level SEP nor individual-level SEP was associated with perceived racial discrimination.
Conclusion. Individual and neighborhood-level SEP may be important in understanding how racial discrimination is perceived, reported, processed, and how it may influence health. In order to fully assess the role of racism in future studies, inclusion of additional dimensions of discrimination may be warranted
Effects of Pituitary Stalk-transection and Type of Barrier on Pituitary and Luteal Function During the Estrous Cycle of the Ewe
Effects of pituitary stalk-transection on plasma concentrations of luteinizing hormone (LH), follicle stimulating hormone (FSH) prolactin (PRL) and progesterone were investigated during the estrous cycle of ewes. Pituitary stalk (SS) or sham (SH) transection was performed on day 1 (estrus = day 0) of the estrous cycle. A Teflon or Silastic barrier was placed between the cut ends of the stalk to prevent reorganization of the portal vasculature. Immediately following surgery, pulsatile administration of gonadotropin releasing hormone (GnRH, 200 ng/hr) or .9% NaCl was initiated and continued for the duration of the experiment. Estradiol benzoate (EB, 50 μg im) was administered to all ewes on day 3. Mean concentrations of LH were greater in SS ewes than in SH ewes (P\u3c.05). There was a trend (P=.06) for the concentration of LH to be higher in ewes with Teflon compared with Silastic barriers between the cut ends of the stalk. Infusion of GnRH elevated concentrations of LH in both SS and SH ewes (P\u3c.05). Concentrations of progesterone were reduced (P\u3c.01) in saline-infused SS ewes while infusion of GnRH in SS ewes maintained concentrations of progesterone similar to saline-infused SH ewes. The concentrations of FSH or PRL were unaffected by SS, type of barrier or treatment with GnRH. Administration of EB failed to induce a surge of LH except in a SH ewe infused with GnRH. Ewes were more responsive to infusion of GnRH following SS than after SH as reflected by increased plasma concentrations of LH and progesterone
Gonadotropin Concentrations, Follicular Development, and Luteal Function in Pituitary Stalk-transfected Ewes Treated with Bovine Follicular Fluid
Two experiments, each arranged as a 2 x 2 factorial, were conducted in ewes to examine direct effects of bovine follicular fluid (bFF) on follicular development and luteal function and to further characterize follicular development and luteal function after pituitary stalk transection (SS). In Exp. 1, ewes were sham-operated or SS on d 6 of an estrous cycle and received 5 ml of saline or bFF three times daily on d 5 through 11 of the same cycle. In Exp. 2, all ewes were SS on d 6 of an estrous cycle and treated with saline or bFF three times daily on d 5 through 11 and with ovine FSH (60 micrograms; NIADDK-oFSH-16) or saline (1.2 ml) from d 7 to 11. In Exp. 2, ewes were ovariectomized on d 11 to assess effects of treatments on follicular development and luteal function. In both experiments, concentrations (ng/ml) of FSH on d 7 were suppressed (P less than or equal to .005) by bFF compared with saline (.50 +/- .17 vs 1.63 +/- .15) and remained suppressed (P less than or equal to .005) through d 11 (.46 +/- .12 vs 1.54 +/- .12). Replacement therapy (oFSH) restored concentrations of FSH. Concentrations of LH were not affected by bFF but were elevated (P less than or equal to .05) 1 d after SS (d 7; .88 +/- .09 vs .56 +/- .09) and remained elevated (P less than or equal to .05; 1.31 +/- .20 vs .65 +/- .11) from d 6 through 11. Concentrations of progesterone were unaffected by SS
Preliminary Results from NEOWISE: An Enhancement to the Wide-field Infrared Survey Explorer for Solar System Science
The Wide-field Infrared Survey Explorer (WISE) has surveyed the entire sky at four infrared wavelengths with greatly improved sensitivity and spatial resolution compared to its predecessors, the Infrared Astronomical Satellite and the Cosmic Background Explorer. NASA's Planetary Science Division has funded an enhancement to the WISE data processing system called "NEOWISE" that allows detection and archiving of moving objects found in the WISE data. NEOWISE has mined the WISE images for a wide array of small bodies in our solar system, including near-Earth objects (NEOs), Main Belt asteroids, comets, Trojans, and Centaurs. By the end of survey operations in 2011 February, NEOWISE identified over 157,000 asteroids, including more than 500 NEOs and ~120 comets. The NEOWISE data set will enable a panoply of new scientific investigations
Survey Simulations of a New Near-Earth Asteroid Detection System
We have carried out simulations to predict the performance of a new
space-based telescopic survey operating at thermal infrared wavelengths that
seeks to discover and characterize a large fraction of the potentially
hazardous near-Earth asteroid (NEA) population. Two potential architectures for
the survey were considered: one located at the Earth-Sun L1 Lagrange point, and
one in a Venus-trailing orbit. A sample cadence was formulated and tested,
allowing for the self-follow-up necessary for objects discovered in the daytime
sky on Earth. Synthetic populations of NEAs with sizes >=140 m in effective
spherical diameter were simulated using recent determinations of their physical
and orbital properties. Estimates of the instrumental sensitivity, integration
times, and slew speeds were included for both architectures assuming the
properties of new large-format 10 um detector arrays capable of operating at
~35 K. Our simulation included the creation of a preliminary version of a
moving object processing pipeline suitable for operating on the trial cadence.
We tested this pipeline on a simulated sky populated with astrophysical sources
such as stars and galaxies extrapolated from Spitzer and WISE data, the catalog
of known minor planets (including Main Belt asteroids, comets, Jovian Trojans,
etc.), and the synthetic NEA model. Trial orbits were computed for simulated
position-time pairs extracted from the synthetic surveys to verify that the
tested cadence would result in orbits suitable for recovering objects at a
later time. Our results indicate that the Earth-Sun L1 and Venus-trailing
surveys achieve similar levels of integral completeness for potentially
hazardous asteroids larger than 140 m; placing the telescope in an interior
orbit does not yield an improvement in discovery rates. This work serves as a
necessary first step for the detailed planning of a next-generation NEA survey.Comment: AJ accepted; corrected typ
Horizontal band-saw
The effect of various parameters on the performance of the band saw
when cutting mild steel-with a 10 t.p.i. raker-set blade were established
over a limited range. These are discussed fully in the ‘conclusions'.
With this limited survey it was not found possible to establish the optimum
conditions of operation
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