2,360 research outputs found
The Educational Experiences of African-American Males in Special Education Through Counter-stories
The current study aimed to fill a gap in the literature by using counter-storytelling, through the theoretical framework of Critical Race Theory, to explore the historically poor educational outcomes and disproportionate representation of African-American males in special education. Firsthand accounts of African-American male students’ experiences within special education and parents’ experiences with their children’s education were collected. Findings suggested that African-American males in special education take responsibility for their behavior and learning and that their parents play an essential role as advocates. A sharp contrast was also found between parents and their children as parents saw a broken system while students saw themselves as the problem. Furthermore, findings showed that despite students’ and parents’ belief that the current educational placement was appropriate, the achievement gap between white and African-American students still persisted. The study’s findings indicate that educators need to be conscientious of the potential for students to readily internalize both negative and positive interactions within their environment, that schools engage students and parents more deliberately when planning curriculum and instruction, and be receptive to both student and parent voices in order to help shape curriculum and instruction, and be reflective of how their own culture may positively or negatively influence curriculum and instruction in the classroom. It is clear how critically important these factors are in impacting the quality of programs and services African-American males in special education receive, and thus should be at the forefront of educators’ minds when designing curriculum and instruction.Ed.D.College of Education, Health & Human ServicesUniversity of Michigan-Dearbornhttps://deepblue.lib.umich.edu/bitstream/2027.42/150687/1/Matthew T. Bennett Dissertation.pdfDescription of Matthew T. Bennett Dissertation.pdf : Dissertatio
Ezetimibe is effective when added to maximally tolerated lipid lowering therapy in patients with HIV
To determine the efficacy and safety of adding ezetimibe to maximally tolerated lipid lowering therapy in patients with HIV dyslipidemia
Are HIV positive patients resistant to statin therapy?
<p>Abstract</p> <p>Background</p> <p>Patients with HIV are subject to development of HIV metabolic syndrome characterized by dyslipidemia, lipodystrophy and insulin resistance secondary to highly active antiretroviral therapy (HAART). Rosuvastatin is a highly potent HMG-CoA reductase inhibitor. Rosuvastatin is effective at lowering LDL and poses a low risk for drug-drug interaction as it does not share the same metabolic pathway as HAART drugs. This study sought to determine the efficacy of rosuvastatin on lipid parameters in HIV positive patients with HIV metabolic syndrome.</p> <p>Results</p> <p>Mean TC decreased from 6.54 to 4.89 mmol/L (25.0% reduction, p < 0.001). Mean LDL-C decreased from 3.39 to 2.24 mmol/L (30.8% reduction, p < 0.001). Mean HDL rose from 1.04 to 1.06 mmol/L (2.0% increase, p = ns). Mean triglycerides decreased from 5.26 to 3.68 mmol/L (30.1% reduction, p < 0.001). Secondary analysis examining the effectiveness of rosuvastatin monotherapy (n = 70) vs. rosuvastatin plus fenofibrate (n = 43) showed an improvement of 21.3% in TG and a decrease of 4.1% in HDL-C in the monotherapy group. The rosuvastatin plus fenofibrate showed a greater drop in triglycerides (45.3%, p < 0.001) and an increase in HDL of 7.6% (p = 0.08).</p> <p>Conclusion</p> <p>This study found that rosuvastatin is effective at improving potentially atherogenic lipid parameters in HIV-positive patients. The lipid changes we observed were of a smaller magnitude compared to non-HIV subjects. Our results are further supported by a small, pilot trial examining rosuvastatin effectiveness in HIV who reported similar median changes from baseline of -21.7% (TC), -22.4% (LDL-C), -30.1% (TG) with the exception of a 28.5% median increase in HDL. In light of the results revealed by this pilot study, clinicians may want to consider a possible resistance to statin therapy when treating patients with HIV metabolic syndrome.</p
Rapidly Rotating Lenses: Repeating features in the lightcurves of short period binary microlenses
Microlensing is most sensitive to binary lenses with relatively large orbital
separations, and as such, typical binary microlensing events show little or no
orbital motion during the event. However, despite the strength of binary
microlensing features falling off rapidly as the lens separation decreases, we
show that it is possible to detect repeating features in the lightcurve of
binary microlenses that complete several orbits during the microlensing event.
We investigate the lightcurve features of such Rapidly Rotating Lens (RRL)
events. We derive analytical limits on the range of parameters where these
effects are detectable, and confirm these numerically. Using a population
synthesis Galactic model we estimate the RRL event rate for a ground-based and
space-based microlensing survey to be 0.32fb and 7.8fb events per year
respectively, assuming year-round monitoring and where fb is the binary
fraction. We detail how RRL event parameters can be quickly estimated from
their lightcurves, and suggest a method to model RRL events using timing
measurements of lightcurve features. Modelling RRL lightcurves will yield the
lens orbital period and possibly measurements of all orbital elements including
the inclination and eccentricity. Measurement of the period from the lightcurve
allows a mass-distance relation to be defined, which when combined with a
measurement of microlens parallax or finite source effects, can yield a mass
measurement to a two-fold degeneracy. With sub-percent accuracy photometry it
is possible to detect planetary companions, but the likelihood of this is very
small.Comment: 16 pages, 14 figures, accepted for publication in MNRAS. Equation 21
simplifie
Mortality and recruitment of fire-tolerant eucalypts as influenced by wildfire severity and recent prescribed fire
Mixed-species eucalypt forests of temperate Australia are assumed tolerant of most fire regimes based on the impressive capacity of the dominant eucalypts to resprout. However, empirical data to test this assumption are rare, limiting capacity to predict forest tolerance to emerging fire regimes including more frequent severe wildfires and extensive use of prescribed fire. We quantified tree mortality and regeneration in mixed-species eucalypt forests five years after an extensive wildfire that burnt under extreme fire weather. To examine combined site-level effects of wildfire and prescribed fire, our study included factorial replications of three wildfire severities, assessed as crown scorch and understorey consumption shortly after the wildfire (Unburnt, Low, High), and two times since last preceding fire (30 years since any fire). Our data indicate that while most trees survived low-severity wildfire through epicormic resprouting, this capacity was tested by high-severity wildfire. Five years after the wildfire, percentage mortalities of eucalypts in all size intervals from 10 to >70 cm diameter were significantly greater at High severity than Unburnt or Low severity sites, and included the near loss of the 10–20 cm cohort (93% mortality). Prolific seedling regeneration at High severity sites, and unreliable basal resprouting, indicated the importance of seedling recruitment to the resilience of these firetolerant forests. Recent prescribed fire had no clear effect on forest resistance (as tree survival) to wildfire, but decreased site-level resilience (as recruitment) by increasing mortalities of small stems. Our study indicates that high-severity wildfire has the potential to cause transitions to more open, simplified stand structures through increased tree mortality, including disproportionate losses in some size cohorts. Dependence on seedling recruitment could increase vulnerabilities to subsequent fires and future climates, potentially requiring direct management interventions to bolster forest resilience.Australian Governmen
Modelling the role of groundwater hydro-refugia in East African hominin evolution and dispersal.
Water is a fundamental resource, yet its spatiotemporal availability in East Africa is poorly understood. This is the area where most hominin first occurrences are located, and consequently the potential role of water in hominin evolution and dispersal remains unresolved. Here, we show that hundreds of springs currently distributed across East Africa could function as persistent groundwater hydro-refugia through orbital-scale climate cycles. Groundwater buffers climate variability according to spatially variable groundwater response times determined by geology and topography. Using an agent-based model, grounded on the present day landscape, we show that groundwater availability would have been critical to supporting isolated networks of hydro-refugia during dry periods when potable surface water was scarce. This may have facilitated unexpected variations in isolation and dispersal of hominin populations in the past. Our results therefore provide a new environmental framework in which to understand how patterns of taxonomic diversity in hominins may have developed
Comparing Observed Stellar Kinematics and Surface Densities in a Low-latitude Bulge Field to Galactic Population Synthesis Models
We present an analysis of Galactic bulge stars from Hubble Space Telescope Wide Field Camera 3 observations of the Stanek window (l, b = [0.25,-2.15]) from two epochs approximately two years apart. This data set is adjacent to the provisional Wide-field Infrared Survey Telescope (WFIRST) microlensing field. Proper motions are measured for approximately 115,000 stars down to 28th mag in V band and 25th mag in I band, with accuracies of 0.5 mas yr-1 (20 km s-1) at I ≈ 21. A cut on the longitudinal proper motion μ l allows us to separate disk and bulge populations and produce bulge-only star counts that are corrected for photometric completeness and efficiency of the proper-motion cut. The kinematic dispersions and surface density in the field are compared to the nearby SWEEPS sight line, finding a marginally larger-than-expected gradient in stellar density. The observed bulge star counts and kinematics are further compared to the Besançon, Galaxia, and GalMod Galactic population synthesis models. We find that most of the models underpredict low-mass bulge stars by ∼33% below the main-sequence turnoff, and upwards of ∼70% at redder J and H wavebands. While considering inaccuracies in the Galactic models, we give implications for the exoplanet yield from the WFIRST microlensing mission
Short Term High-Repetition Back Squat Protocol Does Not Improve 5-km Run Performance
International Journal of Exercise Science 13(7): 1770-1782, 2020. The purpose of this study was to evaluate the hypothesis that a novel high-repetition, low-resistance back squat training protocol, designed to stimulate high-intensity interval training, improves 5-km run performance. Fifteen runners [4 male, 11 female; 150 + minutes of endurance exercise/week; age = 22.7 ± 2.0 y; 21.5 ± 2.2 kg/m2 BMI] in this single-group test-retest design completed two weeks of back squats consisting of three sets of 15-24 repetitions at 60% of estimated one-repetition max (1RM), three times per week (1-2 days of rest between sessions). Outcome tests included a 5-km outdoor timed run, laboratory indirect calorimetry to quantify substrate oxidation rates during steady-state submaximal exercise (60% and 70% heart rate max (HRmax)), and estimated 1RM for back squats. Back squat estimated 1RM increased by 20% (58.3 ± 18.5 to 70.2 ± 16.7 kg, P \u3c 0.001). However, 5-km run times due to the back squat protocol did not significantly change (Pre-Squats: 23.9 ± 5.0 vs. Post-Squats: 23.7 ± 4.3 minutes, P = 0.71). Likewise, the squat training program did not significantly alter carbohydrate or lipid oxidation rates during steady-state submaximal exercise at 60% or 70% of HRmax (P values ranged from 0.36 - 0.99). Short term high-repetition back squat training does not appear to impact 5-km run performance or substrate utilization during submaximal exercise
NASA ExoPAG Study Analysis Group 11: Preparing for the WFIRST Microlensing Survey
NASA's proposed WFIRST-AFTA mission will discover thousands of exoplanets
with separations from the habitable zone out to unbound planets, using the
technique of gravitational microlensing. The Study Analysis Group 11 of the
NASA Exoplanet Program Analysis Group was convened to explore scientific
programs that can be undertaken now, and in the years leading up to WFIRST's
launch, in order to maximize the mission's scientific return and to reduce
technical and scientific risk. This report presents those findings, which
include suggested precursor Hubble Space Telescope observations, a
ground-based, NIR microlensing survey, and other programs to develop and deepen
community scientific expertise prior to the mission.Comment: 35 pages, 5 Figures. A brief overview of the findings is presented in
the Executive Summary (2 pages
The Interactive Effect of Major Depression and Nonsuicidal Self-Injury On Current Suicide Risk and Lifetime Suicide Attempts
Objectives: This study examined the main and interactive effects of MDD and lifetime nonsuicidal self-injury (NSSI) on current suicide risk and past suicide attempts. We predicted that individuals with a history of NSSI and current MDD would be at greater suicide risk than those with either risk factor alone. An interaction between lifetime MDD and NSSI was hypothesized for past suicide attempts.
Methods: 204 substance dependent inpatients completed self-report measures and a diagnostic interview.
Results: Patients with both a history of NSSI and current MDD, relative to all other groups, had the greatest suicide risk. No support was found for the lifetime MDD by NSSI interaction.
Conclusion: Findings suggest the relevance of both NSSI and MDD in suicide risk
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