Improving parental engagement for disadvantaged students

Engaging the parents of secondary school students in the educational lives of these young people is a major challenge for most secondary schools. The objectives of this action research project were to: explore the specific types of parental engagement that can be beneficial to learners, to investigate the extent to which students in school A experience the types of parental engagement that have been identified as beneficial, and ascertain whether promoting parental engagement is an effective way to better engage students and parents in education. This project sought to explore these aspects with the families of disadvantaged students, specifically. Whilst data collection was significantly limited by the coronavirus pandemic of 2020, partial data allowed for the tentative conclusions that a robust relationship between school staff, parents, and students is crucial in supporting students engage more readily in school and that this relationship is best promoted by high-quality and regular communication between school staff and the parents of disadvantaged students

Though facing complex challenges, America’s foreign policy strategy must remain a continual work in progress

America today faces a number of complex foreign policy challenges, with few obvious routes towards their successful resolution. In light of this complexity, many may yearn for the clarity of the Cold War, but Daniel J. Sargent warns against this. He writes that the Cold War policy of containment was no roadmap for policy, and that within its relatively loose outlook policymakers improvised and adapted, and pursued diverse agendas. In contemporary foreign policy, strategists must also acknowledge the potential need to change quickly, and the validity of alternative perspectives on the world

ACTIVE JET ACOUSTIC CONTROL OF LOW FREQUENCY, IN-PLANE HELICOPTER HARMONIC NOISE

A new approach to reducing low frequency, in-plane harmonic noise of helicopter rotors is explored theoretically and experimentally in this dissertation. The active jet acoustic control methodology employs on-blade, tip located unsteady air blowing to produce an acoustic anti-noise waveform that reduces or cancels the observed noise at targeted positions in the acoustic far-field of the rotor system. This effectively reduces the distance at which the helicopter rotor can be aurally detected. An extended theoretical model of the subsonic air jet, which is modeled as both a source of mass and momentum, is presented. The model is applied to a baseline, full-scale, medium weight helicopter rotor for both steady and unsteady blowing. Significant reductions in low frequency, in-plane harmonic noise are shown to be possible for the theoretical rotor system by using physically reasonable unsteady jet velocities. A new model-scale active jet acoustic control experimental test rotor system is described in detail. Experimental measurements conducted in the University of Maryland Acoustic Chamber for the ~1/7th rotor, operated at a full-scale hover tip Mach number of 0.661, indicate that active jet acoustic control is a viable option for reducing low frequency, in-plane harmonic noise. Good correlation between theoretical predictions and measured data for four valve control cases are observed in both the time and frequency domains. Model-scale limitations of the tip-jet blowing experiment limited the peak noise level reductions to 30%. However, theory suggests that if the limitations of the model-scale controller are mitigated, much larger noise reductions are possible

All-Comers versus Enrichment Design Strategy in Phase II Trials

Abstract:Designs for biomarker validation have been proposed and used in the phase III oncology clinical trial setting. Broadly, these designs follow either an enrichment (i.e., targeted) strategy or an all-comers (i.e., unselected) strategy. An enrichment design screens patients for the presence or absence of a marker or a panel of markers and then only includes patients who either have or do not have a certain marker characteristic or profile. In contrast, all patients meeting the eligibility criteria (regardless of a particular biomarker status) are entered into an all-comers design. The strength of the preliminary evidence, the prevalence of the marker, the reproducibility and validity of the assay, and the feasibility of real-time marker assessment play a major role in the choice of the design. In this report, we discuss the parameters under which the enrichment or an all-comers design strategy would be appropriate for phase II trials

Genomic advances and their impact on clinical trial design

Medical treatment for patients has historically been based on two primary elements: the expected outcome for the patient, and the ability of treatment to improve the expected outcome. The advance in genomic technologies has the potential to change this paradigm and add substantial value to current medical practice by providing an integrated approach to guide patient-specific treatment selection using the genetic make-up of the disease and the genotype of the patient. Specifically, genomic signatures can aid in patient stratification (risk assessment), treatment response identification (surrogate markers), and/or in differential diagnosis (identifying who is likely to respond to which drug(s)). Several critical issues, including scientific rationale, clinical trial design, marker assessment methods, cost and feasibility have to be carefully considered in the validation of biomarkers through clinical research before they can be routinely integrated into clinical practice. Here, we highlight the impact of genomic advances on various aspects of clinical trial design

Randomized Phase II Trials: Time for a New Era in Clinical Trial Design

AbstractThe classic single-arm oncology phase II trial designs for evaluating an experimental regimen/agent are limited by multiple sources of bias arising from the inability to separate trial effects (such as patient selection, trial eligibility, imaging techniques and assessment schedule, and treatment locations) from treatment effect on clinical outcomes. Changes in patient population based on biologic subsetting, newer imaging technologies, the use of alternative end points, constrained resources, and the multitude of promising therapies for a given disease make randomized phase II designs, with a concurrent control arm where necessary, attractive. In this brief report, we discuss the salient features of the randomized designs for phase II trials, which when properly applied under the constraints of their underlying inference framework can assure optimal use of limited phase III financial and patient resources

Keck Echellette Spectrograph and Imager Observations of Metal-poor Damped Lyα Systems

We present the first results from a survey of SDSS quasars selected for strong H I damped Lyα (DLA) absorption with corresponding low equivalent width absorption from strong low-ion transitions (e.g., C II λ1334 and Si II λ1260). These metal-poor DLA candidates were selected from the SDSS fifth release quasar spectroscopic database, and comprise a large new sample for probing low-metallicity galaxies. Medium-resolution echellette spectra from the Keck Echellette Spectrograph and Imager spectrograph for an initial sample of 35 systems were obtained to explore the metal-poor tail of the DLA distribution and to investigate the nucleosynthetic patterns at these metallicities. We have estimated saturation corrections for the moderately underresolved spectra, and systems with very narrow Doppler parameters (b ≤ 5 km s^(–1)) will likely have underestimated abundances. For those systems with Doppler parameters b > 5 km s^(–1), we have measured low-metallicity DLA gas with [X/H] < –2.4 for at least one of C, O, Si, or Fe. Assuming non-saturated components, we estimate that several DLA systems have [X/H] < –2.8, including five DLA systems with both low equivalent widths and low metallicity in transitions of both C II and O I. All of the measured DLA metallicities, however, exceed or are consistent with a metallicity of at least 1/1000 of solar, regardless of the effects of saturation in our spectra. Our results indicate that the metal-poor tail of galaxies at z ~ 3 drops exponentially at [X/H] ≾ –3. If the distribution of metallicity is Gaussian, the probability of identifying interstellar medium gas with lower abundance is extremely small, and our results suggest that DLA systems with [X/H] < –4.0 are extremely rare, and could comprise only 8 × 10^(–7) of DLA systems. The relative abundances of species within these low-metallicity DLA systems are compared with stellar nucleosynthesis models, and are consistent with stars having masses of 30 M_⊙ < M * < 100 M_⊙. The observed ratio of [C/O] for values of [O/H] < –2.5 exceeds values seen in moderate metallicity DLA systems, and also exceeds theoretical nucleosynthesis predictions for higher mass Population III stars. We also have observed a correlation between the column density N(C IV) with [Si/H] metallicity, suggestive of a trend between mass of the DLA system and its metallicity

What Constitutes Reasonable Evidence of Efficacy and Effectiveness to Guide Oncology Treatment Decisions?

ABSTRACT The need to practice evidence-based medicine is the current prevailing paradigm within the medical community. Evidence to guide practice can and should come from a variety of sources, including clinical trials, observational studies, and meta-analyses of both or either. This paper discusses the relative strengths and weaknesses of data that arise from these various sources. The different types of evidence required to demonstrate &quot;efficacy&quot; versus &quot;effectiveness,&quot; a critical and often overlooked distinction, are discussed. In the genomic age, in which targeted therapies with or without specific biomarkers are emerging in cancer care, new approaches are necessary to generate the evidence required for decision making. The Oncologist 2010;15(suppl 1): 19 -2

In-Flight Array Measurements of Tail Rotor Harmonic Noise

Acoustic data that utilized a unique flying microphone boom array was analyzed using a time domain averaging technique, based on a theoretical tail rotor one-per-rev signal, to obtain tail rotor acoustic time histories for forward and descending flight. This flying microphone array approach provides useful insight into the directivity and noise mechanisms associated with the periodic harmonic noise generated by the Bell 206B tail rotor. Comparisons between linear harmonic noise theory and the time averaged data show good agreement, indicating that the average harmonic noise of the 206B is dominated by thickness noise near the tip-path-plane of the tail rotor and by loading noise at the out-of-plane microphone positions. The measured data also provides trends in the overall sound pressure level (OASPL) with respect to both forward velocity and descent angle. A significant deviation from the average SPL of the harmonic noise levels at high frequencies is also shown