What the Upper Atmospheres of Giant Planets Reveal

The upper atmospheres of the Giant Planets, Jupiter, Saturn, Uranus and Neptune are transition regions between meteorological layers and outer space. As a result of their exceptionally rarefied nature, they are highly sensitive and therefore revealing probes of the forcing exerted both from above and below. This review provides an overview of these upper atmospheres and the major processes that take place within them, including their powerful auroras, the giant planet ‘energy crisis’ and the decay of Saturn’s rings into the planet. We discuss the many remote-sensing tools that have been used to understand them, for example, large ground-based observatories such as the Keck telescope, space-based observatories such as the Hubble Space Telescope and orbiters such as the Cassini spacecraft. Looking into the future, we discuss the possibilities afforded by the latest and next generation of observatories and space missions, such as the James Webb Space Telescope

A multi-stage drop-the-losers design for multi-arm clinical trials

Multi-arm multi-stage trials can improve the efficiency of the drug development process when multiple new treatments are available for testing. A group-sequential approach can be used in order to design multi-arm multi-stage trials, using an extension to Dunnett’s multiple-testing procedure. The actual sample size used in such a trial is a random variable that has high variability. This can cause problems when applying for funding as the cost will also be generally highly variable. This motivates a type of design that provides the efficiency advantages of a group-sequential multi-arm multi-stage design, but has a fixed sample size. One such design is the two-stage drop-the-losers design, in which a number of experimental treatments, and a control treatment, are assessed at a prescheduled interim analysis. The best-performing experimental treatment and the control treatment then continue to a second stage. In this paper, we discuss extending this design to have more than two stages, which is shown to considerably reduce the sample size required. We also compare the resulting sample size requirements to the sample size distribution of analogous group-sequential multi-arm multi-stage designs. The sample size required for a multi-stage drop-the-losers design is usually higher than, but close to, the median sample size of a group-sequential multi-arm multi-stage trial. In many practical scenarios, the disadvantage of a slight loss in average efficiency would be overcome by the huge advantage of a fixed sample size. We assess the impact of delay between recruitment and assessment as well as unknown variance on the drop-the-losers designs

Less Traditional – More Conceptual: Enhancing Student Learning in First-Year Biology

Over the last two decades, a number of influential reports have called for fundamental changes to undergraduate science education. Most importantly, these reports advocate a shift from traditional lecture-based teaching formats to ones that use student-focused pedagogies to encourage deep student learning about key conceptual ideas in science. Based on these reports, and the underlying research, the University of Calgary completed an extensive redesign of its first-year biology courses in 2011, resulting in two courses: Energy Flow in Biological Systems and DNA, Inheritance and Evolution. These courses focus student learning on two foundational concepts and use student-centered pedagogies to encourage the development of critical-thinking and problem-solving skills. Pre/post data collected from one year of the previous introductory courses and two years of the redesigned courses were used to determine the impact of the transition to a conceptual-based curriculum and the incorporation of active learning strategies including clickers and in-class group assignments on student learning gains measured via normalized change using questions from Biological Concept Inventory, Respiration and Photosynthesis Diagnostic Question Clusters and the Conceptual Inventory of Natural Selection. Student motivations and approaches for learning (e.g. deep versus surface approaches) using the published Approaches and Study Skills Inventory for Students (ASSIST) survey and the Experiences of Teaching and Learning Questionnaire (ETLQ). Data show significantly higher learning gains during the two consecutive years of implementation of the redesigned courses than those achieved in the previous format. Additionally, students reported that lecture activities allowed them being more engaged with course content. We are currently analyzing student written responses, which will provide further insight into the impact of course redesign on content knowledge and critical reasoning skills on student success

Evaluating student learning in large introductory biology courses: predictors of student success and lessons for course redesign

In 2009, the University of Calgary began an extensive redesign of its first-year biology courses based on survey feedback from both students and faculty, as well as the extensive literature showing the effectiveness of student-centered pedagogies in enhancing student learning, engagement and retention in large classes. The two newly designed courses, Energy Flow in Biological Systems and DNA, Inheritance and Evolution are concept-based courses that emphasize the integration of key concepts from biomolecules to the biosphere within a student-centered learning environment; these courses begin in Fall 2011. In order to understand the factors influencing student success in first-year biology, we have initiated a three-year mixed-methods investigation of students’ a priori knowledge, motivations, and approaches to learning. In our current first-year courses, we collected data related to changes in both student motivation and learning over the entire first year for 750 students. The strongest predictors of student success, based on grades earned in the lecture component of the course, were multiple-choice pre-test scores (

Statistical consideration when adding new arms to ongoing clinical trials: the potentials and the caveats.

BACKGROUND: Platform trials improve the efficiency of the drug development process through flexible features such as adding and dropping arms as evidence emerges. The benefits and practical challenges of implementing novel trial designs have been discussed widely in the literature, yet less consideration has been given to the statistical implications of adding arms. MAIN: We explain different statistical considerations that arise from allowing new research interventions to be added in for ongoing studies. We present recent methodology development on addressing these issues and illustrate design and analysis approaches that might be enhanced to provide robust inference from platform trials. We also discuss the implication of changing the control arm, how patient eligibility for different arms may complicate the trial design and analysis, and how operational bias may arise when revealing some results of the trials. Lastly, we comment on the appropriateness and the application of platform trials in phase II and phase III settings, as well as publicly versus industry-funded trials. CONCLUSION: Platform trials provide great opportunities for improving the efficiency of evaluating interventions. Although several statistical issues are present, there are a range of methods available that allow robust and efficient design and analysis of these trials

An adaptive two-arm clinical trial using early endpoints to inform decision making : design for a study of sub-acromial spacers for repair of rotator cuff tendon tears

Background There is widespread concern across the clinical and research communities that clinical trials, powered for patient-reported outcomes, testing new surgical procedures are often expensive and time-consuming, particularly when the new intervention is shown to be no better than the standard. Conventional (non-adaptive) randomised controlled trials (RCTs) are perceived as being particularly inefficient in this setting. Therefore, we have developed an adaptive group sequential design that allows early endpoints to inform decision making and show, through simulations and a worked example, that these designs are feasible and often preferable to conventional non-adaptive designs. The methodology is motivated by an ongoing clinical trial investigating a saline-filled balloon, inserted above the main joint of the shoulder at the end of arthroscopic debridement, for treatment of tears of rotor cuff tendons. This research question and setting is typical of many studies undertaken to assess new surgical procedures. Methods Test statistics are presented based on the setting of two early outcomes, and methods for estimation of sequential stopping boundaries are described. A framework for the implementation of simulations to evaluate design characteristics is also described. Results Simulations show that designs with one, two and three early looks are feasible and, with appropriately chosen futility stopping boundaries, have appealing design characteristics. A number of possible design options are described that have good power and a high probability of stopping for futility if there is no evidence of a treatment effect at early looks. A worked example, with code in R, provides a practical demonstration of how the design might work in a real study. Conclusions In summary, we show that adaptive designs are feasible and could work in practice. We describe the operating characteristics of the designs and provide guidelines for appropriate values for the stopping boundaries for the START:REACTS (Sub-acromial spacer for Tears Affecting Rotator cuff Tendons: a Randomised, Efficient, Adaptive Clinical Trial in Surgery) study

Ground-based observations of Saturn’s auroral ionosphere over three days:trends in H3+ temperature, density and emission with Saturn local time and planetary period oscillation

On 19–21 April 2013, the ground-based 10-m W.M. Keck II telescope was used to simultaneously measure View the MathML sourceH3+ emissions from four regions of Saturn’s auroral ionosphere: (1) the northern noon region of the main auroral oval; (2) the northern midnight main oval; (3) the northern polar cap and (4) the southern noon main oval. The View the MathML sourceH3+ emission from these regions was captured in the form of high resolution spectral images as the planet rotated. The results herein contain twenty-three View the MathML sourceH3+ temperatures, column densities and total emissions located in the aforementioned regions – ninety-two data points in total, spread over timescales of both hours and days. Thermospheric temperatures in the spring-time northern main oval are found to be cooler than their autumn-time southern counterparts by tens of K, consistent with the hypothesis that the total thermospheric heating rate is inversely proportional to magnetic field strength. The main oval View the MathML sourceH3+ density and emission is lower at northern midnight than it is at noon, in agreement with a nearby peak in the electron influx in the post-dawn sector and a minimum flux at midnight. Finally, when arranging the northern main oval View the MathML sourceH3+ parameters as a function of the oscillation period seen in Saturn’s magnetic field – the planetary period oscillation (PPO) phase – we see a large peak in View the MathML sourceH3+ density and emission at ∼115° northern phase, with a full-width at half-maximum (FWHM) of ∼44°. This seems to indicate that the influx of electrons associated with the PPO phase at 90° is responsible at least in part for the behavior of all View the MathML sourceH3+ parameters. A combination of the View the MathML sourceH3+ production and loss timescales and the ±10° uncertainty in the location of a given PPO phase are likely, at least in part, to be responsible for the observed peaks in View the MathML sourceH3+ density and emission occurring at a later time than the peak precipitation expected at 90° PPO phase

Clinical effectiveness and cost-effectiveness of a brief accessible cognitive behavioural therapy programme for stress in school-aged adolescents (BESST): a cluster randomised controlled trial in the UK

Background: Depression and anxiety are increasingly prevalent in adolescents. The Brief Educational Workshops in Secondary Schools Trial investigated the effectiveness of a brief accessible stress workshop programme for 16–18-year olds. We aimed to investigate the clinical effectiveness and cost-effectiveness of the DISCOVER cognitive behavioural therapy (CBT) workshop on symptoms of depression in 16–18-year-olds at 6 months compared with treatment-as usual. Methods: We conducted a multicentre, cluster randomised controlled trial in UK schools or colleges with sixth forms to evaluate clinical effectiveness and cost-effectiveness of a brief CBT workshop (DISCOVER) compared with treatment-as-usual. We planned to enrol 60 schools and 900 adolescents, using a self-referral system to recruit participants. Schools were randomised in a 1:1 ratio for participants to receive either the DISCOVER workshop ortreatment-as-usual, stratified by site and balanced on school size and index of multiple deprivation. Participants were included if they were 16–18 years old, attending for the full school year, seeking help for stress, and fluent in English and able to provide written informed consent. The outcome assessors, senior health economist, senior statistician,and chief investigator were masked. People with lived experience were involved in the study. The primary outcome was depression symptoms measured with the Mood and Feelings Questionnaire (MFQ) at 6-month follow-up, in the intention-to-treat population of all participants with full covariate data. The trial was registered with the ISRCTNregistry (ISRCTN90912799).Findings: 111 schools were invited to participate in the study, seven were deemed ineligible, and 47 did not provide consent. Between Oct 4, 2021, and Nov 10, 2022, 933 students at 57 schools were screened for eligibility, seven were not eligible for inclusion, and 26 did not attend the baseline meeting and assessment, resulting in 900 adolescentsparticipating in the study. The DISCOVER group included 443 participants (295 [67%] female and 136 [31%] male) and the treatment-as-usual group included 457 participants (346 [76%] female and 92 [20%] male). 468 (52%) of the 900 participants were White, and the overall age of the participants was 17·2 years (SD 0·6). 873 (97%) adolescents were followed up in the intention-to-treat population. The primary intention-to-treat analysis (n=854) found anadjusted mean difference in MFQ of –2·06 (95% CI –3·35 to –0·76; Cohen’s d=–0·17; p=0·0019) at the 6-month follow-up, indicating a clinical improvement in the DISCOVER group. The probability that DISCOVER is cost- effective compared with treatment-as-usual ranged from 61% to 78% at a £20000 to £30000 per quality-adjusted life-year threshold. Nine adverse events (two of which were classified as serious) were reported in the DISCOVER groupand 14 (two of which were classified as serious) were reported in the treatment-as-usual group.Interpretation: Our findings indicate that the DISCOVER intervention is modestly clinically effective and economically viable and could be a promising early intervention in schools. Given the importance of addressing mental health needs early in this adolescent population, additional research is warranted to explore this intervention