1,470 research outputs found
Options and Limits in a Woman\u27s World
This is a study of women who are ascribed the role of mother, but who would also like to pursue a satisfying career. These women experience multiple demands when trying to fulfill these multiple roles. The study focused on how women integrate motherhood and employment. The methodology employed in this study was qualitative. Information was solicited through the use of informal personal interviews conducted by the researcher. A single hour interview was conducted with each participant in the research project. The sample consisted of 10 full - time working mothers who volunteered to participate in the project.
The purpose of this study was of a practical nature. It is hoped that the analysis of the information may be helpful to women experiencing the dilemma of multiple roles, as well as educators, physicians, and counselors who will increasingly face these issues in the 1990s
Exercise training ameliorates progressive renal disease in rats with subtotal nephrectomy
Exercise training ameliorates progressive renal disease in rats with subtotal nephrectomy. To determine the effect of chronic exercise training on renal function in animals with moderate renal insufficiency, rats with 75% renal ablation were either exercise trained by swimming for two months or remained sedentary. Glomerular filtration rate was significantly higher in trained (1.89 ± 0.07 ml/min) than in sedentary rats (1.52 ± 0.11 ml/min). No change was observed in renal blood flow or the degree of hypertension. Proteinuria was reduced in trained (13.6 ± 4.9 mg/24 hr) compared to sedentary animals (33.5 ± 9.2 mg/24 hr). The degree of glomerulosclerosis was much less prominent in trained animals. Plasma, low-density lipoprotein cholesterol-levels and total triglycerides were reduced in trained compared to sedentary rats. This study suggests that chronic exercise training ameliorates the progression of renal disease and improves plasma lipids in rats with moderate renal insufficiency. The mechanism for this improvement in renal function appears to be independent of the influence of systemic blood pressure
Spitzer spectral line mapping of protostellar outflows: II H2 emission in L1157
We present an analysis of Spitzer-IRS spectroscopic maps of the L1157
protostellar outflow in the H2 pure-rotational lines from S(0) to S(7). The aim
of this work is to derive the physical conditions pertaining to the warm
molecular gas and study their variations within the flow. The mid-IR H2
emission follows the morphology of the precessing flow, with peaks correlated
with individual CO clumps and H2 2.12{\mu}m ro-vibrational emission. More
diffuse emission delineating the CO cavities is detected only in the low-laying
transitions, with J(lower) less or equal to 2. The H2 line images have been
used to construct 2D maps of N(H2), H2 ortho-to-para ratio and temperature
spectral index beta, in the assumption of a gas temperature stratification
where the H2 column density varies as T^(beta). Variations of these parameters
are observed along the flow. In particular, the ortho-to-para ratio ranges from
0.6 to 2.8, highlighting the presence of regions subject to recent shocks where
the ortho-to-para ratio has not had time yet to reach the equilibrium value.
Near-IR spectroscopic data on ro-vibrational H2 emission have been combined
with the mid-IR data and used to derive additional shock parameters in the
brightest blue- and red-shifted emission knots. A high abundance of atomic
hydrogen (H/H2 about 0.1-0.3) is implied by the observed H2 column densities,
assuming n(H2) values as derived by independent SiO observations. The presence
of a high fraction of atomic hydrogen, indicates that a partially-dissociative
shock component should be considered for the H2 excitation in these localized
regions. However, planar shock models, either of C- or J-type, are not able to
consistently reproduce all the physical parameters derived from our analysis of
the H2 emission. Globally, H2 emission contributes to about 50% of the total
shock radiated energy in the L1157 outflow.Comment: 31 pages, 9 figure, Accepted for publication on Ap
Observation of band structure and density of states effects in Co-based magnetic tunnel junctions
Utilizing Co/AlO/Co magnetic tunnel junctions (MTJs) with Co
electrodes of different crystalline phases, a clear relationship between
electrode structure and junction transport properties is presented. For
junctions with one fcc(111) textured and one polycrystalline (poly-phase and
poly-directional) Co electrode, a strong asymmetry is observed in the
magnetotransport properties, while when both electrodes are polycrystalline the
magnetotransport is essentially symmetric. These observations are successfully
explained within a model based on ballistic tunneling between the calculated
band structures (DOS) of fcc-Co and hcp-Co.Comment: 4 pages, 3 figures, submitted to Phys. Rev. Let
Integrin α6β4 Promotes Autocrine Epidermal Growth Factor Receptor (EGFR) Signaling to Stimulate Migration and Invasion toward Hepatocyte Growth Factor (HGF)
Integrin α6β4 is up-regulated in pancreatic adenocarcinomas where it contributes to carcinoma cell invasion by altering the transcriptome. In this study, we found that integrin α6β4 up-regulates several genes in the epidermal growth factor receptor (EGFR) pathway, including amphiregulin (AREG), epiregulin (EREG), and ectodomain cleavage protease MMP1, which is mediated by promoter demethylation and NFAT5. The correlation of these genes with integrin α6β4 was confirmed in The Cancer Genome Atlas Pancreatic Cancer Database. Based on previous observations that integrin α6β4 cooperates with c-Met in pancreatic cancers, we examined the impact of EGFR signaling on hepatocyte growth factor (HGF)-stimulated migration and invasion. We found that AREG and EREG were required for autocrine EGFR signaling, as knocking down either ligand inhibited HGF-mediated migration and invasion. We further determined that HGF induced secretion of AREG, which is dependent on integrin-growth factor signaling pathways, including MAPK, PI3K, and PKC. Moreover, matrix metalloproteinase activity and integrin α6β4 signaling were required for AREG secretion. Blocking EGFR signaling with EGFR-specific antibodies or an EGFR tyrosine kinase inhibitor hindered HGF-stimulated pancreatic carcinoma cell chemotaxis and invasive growth in three-dimensional culture. Finally, we found that EGFR was phosphorylated in response to HGF stimulation that is dependent on EGFR kinase activity; however, c-Met phosphorylation in response to HGF was unaffected by EGFR signaling. Taken together, these data illustrate that integrin α6β4 stimulates invasion by promoting autocrine EGFR signaling through transcriptional up-regulation of key EGFR family members and by facilitating HGF-stimulated EGFR ligand secretion. These signaling events, in turn, promote pancreatic carcinoma migration and invasion
Matrix GLA Protein Function in Human Trabecular Meshwork Cells: Inhibition of BMP2-Induced Calcification Process
The matrix GLA (MGP) gene has been found to be among the 10 most highly expressed genes in the human trabecular meshwork (TM), and its expression is affected by conditions associated with glaucoma. Because MGP protein has been shown to play a key role in inhibiting calcification in cartilage and arterial vessels, MGP’s function in human TM was investigated
Proinsulin Secretion Is a Persistent Feature of Type 1 Diabetes
OBJECTIVE:
Abnormally elevated proinsulin secretion has been reported in type 2 and early type 1 diabetes when significant C-peptide is present. We questioned whether individuals with long-standing type 1 diabetes and low or absent C-peptide secretory capacity retained the ability to make proinsulin.
RESEARCH DESIGN AND METHODS:
C-peptide and proinsulin were measured in fasting and stimulated sera from 319 subjects with long-standing type 1 diabetes (≥3 years) and 12 control subjects without diabetes. We considered three categories of stimulated C-peptide: 1) C-peptide positive, with high stimulated values ≥0.2 nmol/L; 2) C-peptide positive, with low stimulated values ≥0.017 but <0.2 nmol/L; and 3) C-peptide <0.017 nmol/L. Longitudinal samples were analyzed from C-peptide-positive subjects with diabetes after 1, 2, and 4 years.
RESULTS:
Of individuals with long-standing type 1 diabetes, 95.9% had detectable serum proinsulin (>3.1 pmol/L), while 89.9% of participants with stimulated C-peptide values below the limit of detection (<0.017 nmol/L; n = 99) had measurable proinsulin. Proinsulin levels remained stable over 4 years of follow-up, while C-peptide decreased slowly during longitudinal analysis. Correlations between proinsulin with C-peptide and mixed-meal stimulation of proinsulin were found only in subjects with high stimulated C-peptide values (≥0.2 nmol/L). Specifically, increases in proinsulin with mixed-meal stimulation were present only in the group with high stimulated C-peptide values, with no increases observed among subjects with low or undetectable (<0.017 nmol/L) residual C-peptide.
CONCLUSIONS:
In individuals with long-duration type 1 diabetes, the ability to secrete proinsulin persists, even in those with undetectable serum C-peptide
Spitzer spectral line mapping of protostellar outflows: I. Basic data and outflow energetics
We report the results of spectroscopic mapping observations carried out
toward protostellar outflows in the BHR71, L1157, L1448, NGC 2071, and VLA 1623
molecular regions using the Infrared Spectrograph (IRS) of the Spitzer Space
Telescope. These observations, covering the 5.2 - 37 micron spectral region,
provide detailed maps of the 8 lowest pure rotational lines of molecular
hydrogen and of the [SI] 25.25 micron and [FeII] 26.0 micron fine structure
lines. The molecular hydrogen lines, believed to account for a large fraction
of the radiative cooling from warm molecular gas that has been heated by a
non-dissociative shock, allow the energetics of the outflows to be elucidated.
Within the regions mapped towards these 5 outflow sources, total H2
luminosities ranging from 0.02 to 0.75 L(solar) were inferred for the sum of
the 8 lowest pure rotational transitions. By contrast, the much weaker [FeII]
26.0 micron fine structure transition traces faster, dissociative shocks; here,
only a small fraction of the fast shock luminosity emerges as line radiation
that can be detected with Spitzer/IRS.Comment: 38 pages including 17 figures. Accepted for publication in Ap
Kinetic Properties of a Bose-Einstein Gas at Finite Temperature
We study, in the framework of the Boltzmann-Nordheim equation (BNE), the
kinetic properties of a boson gas above the Bose-Einstein transition
temperature . The BNE is solved numerically within a new algorithm, that
has been tested with exact analytical results for the collision rate of an
homogeneous system in thermal equilibrium. In the classical regime (), the relaxation time of a quadrupolar deformation in momentum space is
proportional to the mean free collision time .
Approaching the critical temperature (), quantum statistic
effects in BNE become dominant, and the collision rate increases dramatically.
Nevertheless, this does not affect the relaxation properties of the gas that
depend only on the spontaneous collision term in BNE. The relaxation time
is proportional to , exhibiting a critical
slowing down. These phenomena can be experimentally confirmed looking at the
damping properties of collective motions induced on trapped atoms. The
possibility to observe a transition from collisionless (zero-sound) to
hydrodynamic (first-sound) is finally discussed.Comment: RevTeX, 5 figures. Submitted to Phys. Rev.
Evaluation of Stepped Care for Chronic Pain (ESCAPE) in Veterans of the Iraq and Afghanistan Conflicts A Randomized Clinical Trial
IMPORTANCE:
Despite the prevalence and the functional, psychological, and economic impact of chronic pain, few intervention studies of treatment of chronic pain in veterans have been performed.
OBJECTIVE:
To determine whether a stepped-care intervention is more effective than usual care, as hypothesized, in reducing pain-related disability, pain interference, and pain severity.
DESIGN, SETTING, AND PARTICIPANTS:
We performed a randomized clinical trial comparing stepped care with usual care for chronic pain. We enrolled 241 veterans from Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn with chronic (>3 months) and disabling (Roland Morris Disability Scale score, ≥7) musculoskeletal pain of the cervical or lumbar spine or extremities (shoulders, knees, and hips) in the Evaluation of Stepped Care for Chronic Pain (ESCAPE) trial from December 20, 2007, through June 30, 2011. The 9-month follow-up was completed by April 2012. Patients received treatment at a postdeployment clinic and 5 general medicine clinics at a Veterans Affairs medical center.
INTERVENTIONS:
Step 1 included 12 weeks of analgesic treatment and optimization according to an algorithm coupled with pain self-management strategies; step 2, 12 weeks of cognitive behavioral therapy. All intervention aspects were delivered by nurse care managers.
MAIN OUTCOMES AND MEASURES:
Pain-related disability (Roland Morris Disability Scale), pain interference (Brief Pain Inventory), and pain severity (Graded Chronic Pain Scale).
RESULTS:
The primary analysis included 121 patients receiving the stepped-care intervention and 120 patients receiving usual care. At 9 months, the mean decrease from baseline in the Roland Morris Disability Scale score was 1.7 (95% CI, -2.6 to -0.9) points in the usual care group and 3.7 (95% CI, -4.5 to -2.8) points in the intervention group (between-group difference, -1.9 [95% CI, -3.2 to -0.7] points; P=.002). The mean decrease from baseline in the Pain Interference subscale score of the Brief Pain Inventory was 0.9 points in the usual care group and 1.7 points in the intervention group (between-group difference, -0.8 [95% CI, -1.3 to -0.3] points; P=.003). The Graded Chronic Pain Scale severity score was reduced by 4.5 points in the usual care group and 11.1 points in the intervention group (between-group difference, -6.6 [95% CI, -10.5 to -2.7] points; P=.001).
CONCLUSIONS AND RELEVANCE:
A stepped-care intervention that combined analgesics, self-management strategies, and brief cognitive behavioral therapy resulted in statistically significant reductions in pain-related disability, pain interference, and pain severity in veterans with chronic musculoskeletal pain
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