143 research outputs found
A gas-rich nuclear bar fuelling a powerful central starburst in NGC 2782
We present evidence that the peculiar interacting starburst galaxy NGC 2782
(Arp 215) harbors a gas-rich nuclear stellar bar feeding an M82-class powerful
central starburst, from a study based on OVRO CO (J=1->0) data, WIYN BVR &
Halpha observations, along with available NIR images, a 5 GHz RC map and HST
images. NGC 2782 harbors a clumpy, bar-like CO feature of radius ~ 7.5'' (1.3
kpc) which leads a nuclear stellar bar of similar size. The nuclear CO bar is
massive: it contains ~2.5x10**9 M_sun of molecular gas, which makes up ~ 8 % of
the dynamical'mass present within a 1.3 kpc radius. Within the CO bar, emission
peaks in two extended clumpy lobes which lie on opposite sides of the nucleus,
separated by ~ 6'' (1 kpc). Between the CO lobes, in the inner 200 pc radius,
resides a powerful central starburst which is forming stars at a rate of 3 to 6
M_sun yr-1. While circular motions dominate the CO velocity field, the CO lobes
show weak bar-like streaming motions on the leading side of the nuclear stellar
bar, suggestive of gas inflow. We estimate semi-analytically the gravitational
torque from the nuclear stellar bar on the gas, and suggest large gas inflow
rates from the CO lobes into the central starburst. These observations, which
are amongst the first ones showing a nuclear stellar bar fuelling molecular gas
into an intense central starburst, are consistent with simulations and theory
which suggest that nuclear bars provide an efficient way of transporting gas
closer to the galactic center to fuel central activity. Furthermore, several
massive clumps are present at low radii, and dynamical friction might produce
further gas inflow. We suggest that the nuclear molecular gas bas and central
activity will be very short-lived, likely disappearing within 5x10**8 years.Comment: Accepted by the Astrophysical Journal, 10 pages, Latex with
emulateapj.sty, apjfonts.sty, 10 postscript & 2 gif figure
NGC 4314. IV. Photometry of Star Clusters with Hubble Space Telescope - History of Star Formation in the Vicinity of a Nuclear Ring
Using HST WFPC2 images, we have obtained U, B, V, I, and H-alpha photometry
for 76 star clusters in the nuclear star-forming ring of the barred spiral
galaxy NGC 4314. These clusters are likely associated with an inner Inner
Lindblad Resonance, or IILR. The blue colors and H-alpha emission for most of
these clusters imply very young ages of 1-15 Myr. Age estimates based on
several reddening-free parameters indicate that the present epoch of star
formation has lasted at least 30 Myr. By estimating the masses of stars in the
clusters and comparing with the H-alpha luminosity, we conclude that a
significant fraction of ongoing star formation in the nuclear ring of NGC 4314
occurs in clusters. The cluster masses identify these as young open clusters,
not young globular clusters. Further out in the galaxy, just exterior to the
ring of young stars, previous ground-based observations revealed two symmetric
stellar spiral arms which may be associated with an outer Inner Lindblad
Resonance, or OILR. With our HST data, we have revealed part of this structure
and its colors in more detail. The spiral arm colors are consistent with
stellar ages between 40 and 200 Myr. The age difference between the inner ring
of young stars (IILR) and the larger oval-like feature containing the blue arms
(OILR) supports an interpretation of the morphology of the nuclear region of
NGC 4314 that requires a reservoir of gas that becomes more compact over time.
We speculate that as the gas distribution becomes more centrally concentrated,
it interacts with these two resonances. Each resonance triggers star formation,
resulting in two distinct epochs of star formation.Comment: To appear in The Astronomical Journal, March 2002. For a version with
higher quality figures, see
http://clyde.as.utexas.edu/pub/galaxy/N4314NEW/AJPAPER/BenedictR7.ps.g
The association of health literacy and blood pressure reduction in a cohort of patients with hypertension: The heart healthy lenoir trial
Lower health literacy is associated with poorer health outcomes. Few interventions poised to mitigate the impact of health literacy in hypertensive patients have been published. We tested if a multilevel quality improvement intervention could differentially improve Systolic Blood Pressure (SBP) more so in patients with low vs. higher health literacy
A pilot study comparing two weight loss maintenance interventions among low-income, mid-life women
Abstract: Background: Despite high obesity prevalence rates, few low-income midlife women participate in weight loss maintenance trials. This pilot study aims to assess the effectiveness of two weight loss maintenance interventions in this under-represented population. Methods: Low-income midlife women who completed a 16-week weight loss intervention and lost ≥ 8 lbs (3.6 kg) were eligible to enroll in one of two 12-month maintenance programs. The programs were similar in content and had the same number of total contacts, but were different in the contact modality (Phone + Face-to-Face vs. Face-to- Face Only). Two criteria were used to assess successful weight loss maintenance at 12 months: (1) retaining a loss of ≥ 5% of body weight from the start of the weight loss phase and (2) a change in body weight of < 3%, from the start to the end of the maintenance program. Outcome measures of changes in physiologic and psychosocial factors, and evaluations of process measures and program acceptability (measured at 12 months) are also reported. For categorical variables, likelihood ratio or Fisher’s Exact (for small samples) tests were used to evaluate statistically significant relationships; for continuous variables, t-tests or their equivalents were used to assess differences between means and also to identify correlates of weight loss maintenance. Results: Overall, during the 12-month maintenance period, 41% (24/58) of participants maintained a loss of ≥ 5% of initial weight and 43% (25/58) had a <3% change in weight. None of the comparisons between the two maintenance programs were statistically significant. However, improvements in blood pressure and dietary behaviors remained significant at the end of the 12-month maintenance period for participants in both programs. Participant attendance and acceptability were high for both programs. Conclusions: The effectiveness of two pilot 12-month maintenance interventions provides support for further research in weight loss maintenance among high-risk, low-income women. Trial registration ClinicalTrials.gov Identifier: NCT0028830
Applicability of Precision Medicine Approaches to Managing Hypertension in Rural Populations
As part of the Heart Healthy Lenoir Project, we developed a practice level intervention to improve blood pressure control. The goal of this study was: (i) to determine if single nucleotide polymorphisms (SNPs) that associate with blood pressure variation, identified in large studies, are applicable to blood pressure control in subjects from a rural population; (ii) to measure the association of these SNPs with subjects’ responsiveness to the hypertension intervention; and (iii) to identify other SNPs that may help understand patient-specific responses to an intervention. We used a combination of candidate SNPs and genome-wide analyses to test associations with either baseline systolic blood pressure (SBP) or change in systolic blood pressure one year after the intervention in two genetically defined ancestral groups: African Americans (AA) and Caucasian Americans (CAU). Of the 48 candidate SNPs, 13 SNPs associated with baseline SBP in our study; however, one candidate SNP, rs592582, also associated with a change in SBP after one year. Using our study data, we identified 4 and 15 additional loci that associated with a change in SBP in the AA and CAU groups, respectively. Our analysis of gene-age interactions identified genotypes associated with SBP improvement within different age groups of our populations. Moreover, our integrative analysis identified AQP4-AS1 and PADI2 as genes whose expression levels may contribute to the pleiotropy of complex traits involved in cardiovascular health and blood pressure regulation in response to an intervention targeting hypertension. In conclusion, the identification of SNPs associated with the success of a hypertension treatment intervention suggests that genetic factors in combination with age may contribute to an individual’s success in lowering SBP. If these findings prove to be applicable to other populations, the use of this genetic variation in making patient-specific interventions may help providers with making decisions to improve patient outcomes. Further investigation is required to determine the role of this genetic variance with respect to the management of hypertension such that more precise treatment recommendations may be made in the future as part of personalized medicine
A community assessment to inform a multi-level intervention to reduce CVD risk and risk disparities in a rural community
In order to complete a formative evaluation to identify community-level assets and barriers to healthy lifestyle choices, we conducted qualitative interviews, community audits, and secondary data analyses. We solicited local leaders’ perspectives regarding ‘win-ability’ of obesity prevention policy options. Participants noted that many resources were available, yet a barrier was high cost. There were more parks per capita in low-income areas, but they were of lower quality. The most winnable obesity prevention policy was incentives for use of food from local farms. Results are being used to inform an intervention to reduce CVD risk in a rural eastern North Carolina
Patient and Practice Perspectives on Strategies for Controlling Blood Pressure, North Carolina, 2010–2012
IntroductionPatient and practice perspectives can inform development of team-based approaches to improving blood pressure control in primary care. We used a community-based participatory research approach to assess patient and practice perceptions regarding the value of team-based strategies for controlling blood pressure in a rural North Carolina population from 2010 through 2012.MethodsIn-depth interviews were conducted with 41 adults with hypertension, purposely sampled to include diversity of sex, race, literacy, and blood pressure control, and with key office staff at 5 rural primary care practices in the southeastern US “stroke belt.” Interviews explored barriers to controlling blood pressure, the practice’s role in controlling blood pressure, and opinions on the use of team care delivery.ResultsPatients reported that provider strategies to optimize blood pressure control should include regular visits, medication adjustment, side-effect discussion, and behavioral counseling. When discussing team-based approaches to hypertension care, patients valued verbal encouragement, calls from the doctor’s office, and the opportunity to ask questions. However, they voiced concerns about the effect of having too many people involved in their care. Practice staff focused on multiple, broad methods to control blood pressure including counseling, regular office visits, media to improve awareness, and support groups. An explicit focus of delivering care as teams was a newer concept.ConclusionWhen developing a team approach to hypertension treatment, patients value high-quality communication and not losing their primary relationship with their provider. Practice staff members were open to a team-based approach but had limited knowledge of what such an approach would entail
Associations Between Neighborhood-Level Factors Related to a Healthful Lifestyle and Dietary Intake, Physical Activity, and Support for Obesity Prevention Polices Among Rural Adults
To examine cross-sectional associations among neighborhood- and individual-level factors related to a healthful lifestyle and dietary intake, physical activity (PA), and support for obesity prevention polices in rural eastern North Carolina adults
The heart healthy lenoir project-an intervention to reduce disparities in hypertension control: study protocol
Background
Racial disparities in blood pressure control are well established; however the impact of low health literacy (LHL) on blood pressure has garnered less attention. Office based interventions that are created with iterative patient, practice and community stakeholder input and are rolled out incrementally, may help address these disparities in hypertension control. This paper describes our study protocol.
Methods/design
Using a community based participatory research (CBPR) approach, we designed and implemented a cohort study that includes both a practice level and patient level intervention to enhance the care and support of patients with hypertension in primary care practices in a rural region of eastern North Carolina. The study is divided into a formative phase and an ongoing 2.5 year implementation phase. Our main care enhancement activities include the integration of a community health coach, using home blood pressure monitoring in clinical decision making, standardizing care delivery processes, and working to improve medication adherence. Main outcomes include overall blood pressure change, the differential change in blood pressure by race (African American vs. White) and health literacy level (low vs. higher health literacy).
Discussion
Using a community based participatory approach in primary care practice settings has helped to engage patients and practice staff and providers in the research effort and in making practice changes to support hypertension care. Practices have engaged at varying levels, but progress has been made in implementing and iteratively improving upon the interventions to date
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