2,301 research outputs found
When is diabetes distress clinically meaningful?: establishing cut points for the Diabetes Distress Scale.
ObjectiveTo identify the pattern of relationships between the 17-item Diabetes Distress Scale (DDS17) and diabetes variables to establish scale cut points for high distress among patients with type 2 diabetes.Research design and methodsRecruited were 506 study 1 and 392 study 2 adults with type 2 diabetes from community medical groups. Multiple regression equations associated the DDS17, a 17-item scale that yields a mean-item score, with HbA(1c), diabetes self-efficacy, diet, and physical activity. Associations also were undertaken for the two-item DDS (DDS2) screener. Analyses included control variables, linear, and quadratic (curvilinear) DDS terms.ResultsSignificant quadratic effects occurred between the DDS17 and each diabetes variable, with increases in distress associated with poorer outcomes: study 1 HbA(1c) (P < 0.02), self-efficacy (P < 0.001), diet (P < 0.001), physical activity (P < 0.04); study 2 HbA(1c) (P < 0.03), self-efficacy (P < 0.004), diet (P < 0.04), physical activity (P = NS). Substantive curvilinear associations with all four variables in both studies began at unexpectedly low levels of DDS17: the slope increased linearly between scores 1 and 2, was more muted between 2 and 3, and reached a maximum between 3 and 4. This suggested three patient subgroups: little or no distress, <2.0; moderate distress, 2.0-2.9; high distress, ≥3.0. Parallel findings occurred for the DDS2.ConclusionsIn two samples of type 2 diabetic patients we found a consistent pattern of curvilinear relationships between the DDS and HbA(1c), diabetes self-efficacy, diet, and physical activity. The shape of these relationships suggests cut points for three patient groups: little or no, moderate, and high distress
Observations of the Ca II K line in Hel0830A dark points on August 3, 1985
Spectroheliograms taken in the light of He I 10830 A at the National Solar Observatory Vacuum Telescope on Kitt Peak were used to identify coronal holes and bright points (BPs). Target points were identified, coordinates calculated, and spectra recorded. For each spectrum, the difference in wavelength between the Ca II K minimum and the FeI reference line was calculated. It was noteworthy that the overall effect is a blueshift. It should be noted that if material of chromospheric density moves outward at this velocity, it could supply the mass flux of the solar wind if this chromospheric flow was concentrated in a few dozen sources, each of a diameter of a few arc seconds
Stepfamily Relationship Quality and Stepchildren’s Depression in Adolescence and Adulthood
Before reaching adulthood, one third of all youth in the United States will reside in a stepfamily household—a familial context marked by distinct challenges. Relatively few studies have explored family processes that promote youth adjustment in stepfamilies, and even fewer studies have examined these links across adolescence, emerging adulthood, and beyond. To address these gaps, we use a nationally representative sample of 758 adolescent stepchildren to examine the concurrent and long-term influence of mother–child, stepfather–child, nonresident father–child, and stepcouple relationship quality on stepchildren’s depression across three stages of development: adolescence, emerging adulthood, and young adulthood. Results from longitudinal structural equation modeling indicate that higher quality mother–child and stepfather–child relationships are directly associated with reductions in depression during adolescence and indirectly associated with reductions in depression during emerging and young adulthood via prior levels of depression; higher quality stepcouple relationships are directly associated with reductions in depression during emerging and young adulthood
Making automation pay - cost & throughput trade-offs in the manufacture of large composite components
The automation of complex manufacturing operations can provide significant savings over manual processes, and there remains much scope for increasing automation in the production of large scale structural composites. However the relationships between driving variables are complex, and the achievable throughput rate and corresponding cost for a given design are often not apparent. The deposition rate, number of machines required and unit production rates needed are interrelated and consequently the optimum unit cost is difficult to predict. A detailed study of the costs involved for a series of composite wing cover panels with different manufacturing requirements was undertaken. Panels were sized to account for manufacturing requirements and structural load requirements allowing both manual and automated lay-up procedures to influence design. It was discovered that the introduction of automated tape lay-up can significantly reduce material unit cost, and improve material utilisation, however higher production rates are needed to see this benefit
From Solar and Stellar Flares to Coronal Heating: Theory and Observations of How Magnetic Reconnection Regulates Coronal Conditions
There is currently no explanation of why the corona has the temperature and
density it has. We present a model which explains how the dynamics of magnetic
reconnection regulates the conditions in the corona. A bifurcation in magnetic
reconnection at a critical state enforces an upper bound on the coronal
temperature for a given density. We present observational evidence from 107
flares in 37 sun-like stars that stellar coronae are near this critical state.
The model may be important to self-organized criticality models of the solar
corona.Comment: 13 pages, 2 figures, accepted to Ap. J. Lett., February 200
A Longitudinal Analysis of Stepfamily Relationship Quality and Adolescent Physical Health
Approximately one third of youth are estimated to live with a biological parent and stepparent before reaching adulthood. Additional research is warranted whereby stepfamily processes are identified that drive variation in youth adjustment, particularly physical health. We examined stepfather–child, mother–child, and stepcouple relationship quality as predictors of levels and changes in adolescent physical health over time. We used a nationally representative sample of 1,233 adolescents living in biological mother–stepfather families from waves I (1994–1995) and II (1996) of the National Longitudinal Study of Adolescent to Adult Health. We incorporated measures of stepfather–child, mother–child, and stepcouple relationship quality, as well as adolescent reports of 10 physical health symptoms at waves I and II. Structural equation modeling was used to examine associations between wave I stepfamily relationships and adolescent physical symptoms at waves I and II. We used a zero-inflated negative binomial model to establish the validity of wave II adolescent physical symptoms as a predictor of an index of diagnosed chronic illnesses by wave IV (ages 26–32 years).Stepfather–child and mother–child relationship quality were negatively correlated with concurrent levels of adolescent physical symptoms. Stepfather–child relationship quality was negatively associated with change in adolescent physical symptoms over time. Adolescents with higher levels of physical symptoms at wave II were more likely to report chronic illnesses by adulthood. Stepfather–child relationship quality is a robust predictor of adolescent physical health throughout adolescence and is linked to chronic illness diagnoses in young adulthood. Future research should explore further the mechanisms that underlie this association
Detection of Coronal Mass Ejections in V471 Tauri with the Hubble Space Telescope
V471 Tauri, an eclipsing system consisting of a hot DA white dwarf (WD) and a
dK2 companion in a 12.5-hour orbit, is the prototype of the pre-cataclysmic
binaries. The late-type component is magnetically active, due to its being
constrained to rotate synchronously with the short orbital period. During a
program of UV spectroscopy of V471 Tau, carried out with the Goddard High
Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope, we
serendipitously detected two episodes in which transient absorptions in the Si
III 1206 A resonance line appeared suddenly, on a timescale of <2 min. The
observations were taken in a narrow spectral region around Ly-alpha, and were
all obtained near the two quadratures of the binary orbit, i.e., at maximum
projected separation (~3.3 Rsun) of the WD and K star.
We suggest that these transient features arise when coronal mass ejections
(CME's) from the K2 dwarf pass across the line of sight to the WD. Estimates of
the velocities, densities, and masses of the events in V471 Tau are generally
consistent with the properties of solar CME's. Given our detection of 2 events
during 6.8 hr of GHRS observing, along with a consideration of the restricted
range of latitudes and longitudes on the K star's surface that can give rise to
trajectories passing in front of the WD as seen from Earth, we estimate that
the active V471 Tau dK star emits some 100-500 CME's per day, as compared to
1-3 per day for the Sun. The K dwarf's mass-loss rate associated with CME's is
at least (5-25) x 10^{-14} Msun/yr, but it may well be orders of magnitude
higher if most of the silicon is in ionization states other than Si III.Comment: 24 pages AASTeX, 4 figures. Accepted by Astrophysical Journa
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