Preferences, power, and the determination of working hours

Preferences, power, and the determination of working hour

The accuracy of dynamic attitude propagation

Propagating attitude by integrating Euler's equation for rigid body motion has long been suggested for the Earth Radiation Budget Satellite (ERBS) but until now has not been implemented. Because of limited Sun visibility, propagation is necessary for yaw determination. With the deterioration of the gyros, dynamic propagation has become more attractive. Angular rates are derived from integrating Euler's equation with a stepsize of 1 second, using torques computed from telemetered control system data. The environmental torque model was quite basic. It included gravity gradient and unshadowed aerodynamic torques. Knowledge of control torques is critical to the accuracy of dynamic modeling. Due to their coarseness and sparsity, control actuator telemetry were smoothed before integration. The dynamic model was incorporated into existing ERBS attitude determination software. Modeled rates were then used for attitude propagation in the standard ERBS fine-attitude algorithm. In spite of the simplicity of the approach, the dynamically propagated attitude matched the attitude propagated with good gyros well for roll and yaw but diverged up to 3 degrees for pitch because of the very low resolution in pitch momentum wheel telemetry. When control anomalies significantly perturb the nominal attitude, the effect of telemetry granularity is reduced and the dynamically propagated attitudes are accurate on all three axes

The effects of seasonal and latitudinal earth infrared radiance variations on ERBS attitude control

Analysis performed in the Flight Dynamics Facility by the Earth Radiation Budget Satellite (ERBS) Attitude Determination Support team illustrates the pitch attitude control motion and roll attitude errors induced by Earth infrared (IR) horizon radiance variations. IR scanner and inertial reference unit (IRU) pitch and roll flight data spanning 4 years of the ERBS mission are analyzed to illustrate the changes in the magnitude of the errors on time scales of the orbital period, months, and seasons. The analysis represents a unique opportunity to compare prelaunch estimates of radiance-induced attitude errors with flight measurements. As a consequence of this work the following additional information is obtained: an assessment of an average model of these errors and its standard deviation, a measurement to determine and verify previously proposed corrections to the current Earth IR radiance data base, and the possibility of a mean motion model derived from flight data in place of IRU data for ERBS fine attitude determination

Assessing Curriculum Planning for Humanities Inquiry: The Challenges and Opportunities of Poster Presentation

Authentic assessment has been promoted in teacher education as a means of addressing the challenge that pre-service teachers often face in translating theory into practice. In this article, we outline one approach to authentic assessment that utilises a poster format to present a humanities inquiry sequence. Drawing on a practice-based research project into inquiry learning, we explore the challenges and opportunities of this mode of assessment in meeting our curriculum aims. While we acknowledge limitations in this method, we conclude that posters provide a succinct and engaging means of organising, disseminating and assessing inquiry planning in humanities

Effectiveness of lifestyle interventions/culturally bespoke programmes in South Asian ethnic groups targeting weight loss for prevention and/or remission of type 2 diabetes: a systematic review and meta-analysis of intervention trials

People from South Asian heritage are at high risk of type 2 diabetes, but there are limited specific strategies to prevent and manage this condition. The aim was to assess the effectiveness of culturally bespoke lifestyle programmes in South Asians that target weight loss for the prevention or remission of type 2 diabetes mellitus (T2DM). We performed a systematic review and meta-analysis of intervention trials. PubMed, Scopus, MEDLINE (EBSCOhost), CINAHL, PsycINFO and CENTRAL were searched. Human intervention trials (randomised controlled trials and quasi-experimental) investigating the effect of lifestyle interventions on the prevention and remission of T2DM in South Asians were included. Studies including participants at risk of T2DM (prevention trials) and having the disease (remission trials) with duration ≥12 weeks were eligible. For prevention trials, the primary outcome was change in weight (kg) from baseline; for remission trials, it was decrease in HbA1c to non-diabetic levels (HbA1c ≤ 6.5%) without diabetes medications. Prevention trials were separated into (i) lifestyle modification advice and (ii) lifestyle modification advice including a supervised physical activity programme. Twenty-four trials were eligible (21 prevention trials and 3 remission trials). In T2DM prevention trials involving only lifestyle modification advice, the mean postintervention difference in weight between intervention and control groups was -0.65 kg (95% confidence interval [CI]: -1.04, -0.26; p = 0.01). Lifestyle modification advice including a physical activity programme was associated with greater decreases in weight: -1.13 kg (95% CI: -2.04, -0.21; p = 0.02). Fasting blood glucose levels were slightly lower in intervention groups for both intervention subtypes, although there was no significant change in HbA1c levels or 2-h plasma glucose levels. Diabetes remission trials showed potential acceptability but were limited in number and involved a small sample size, and some did not include a control group. In South Asians, lifestyle interventions for prevention of T2DM offer only modest impacts on weight and glucose control and will unlikely reduce diabetes incidence. Alternative lifestyle interventions co-designed with members of the communities and aimed at both prevention and remission of T2DM must be urgently considered. Systematic review registration number: PROSPERO CRD42022385174 https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=385174

Is Breast Cancer Risk Associated with Menopausal Hormone Therapy Modified by Current or Early Adulthood BMI or Age of First Pregnancy?

Menopausal hormone therapy (MHT) has an attenuated effect on breast cancer (BC) risk amongst heavier women, but there are few data on a potential interaction with early adulthood body mass index (at age 20 years) and age of first pregnancy. We studied 56,489 women recruited to the PROCAS (Predicting Risk of Cancer at Screening) study in Manchester UK, 2009-15. Cox regression models estimated the effect of reported MHT use at entry on breast cancer (BC) risk, and potential interactions with a. self-reported current body mass index (BMI), b. BMI aged 20 and c. First pregnancy >30 years or nulliparity compared with first pregnancy <30 years. Analysis was adjusted for age, height, family history, age of menarche and menopause, menopausal status, oophorectomy, ethnicity, self-reported exercise and alcohol. With median follow up of 8 years, 1663 breast cancers occurred. BC risk was elevated amongst current users of combined MHT compared to never users (Hazard ratioHR 1.64, 95% CI 1.32-2.03), risk was higher than for oestrogen only users (HR 1.03, 95% CI 0.79-1.34). Risk of current MHT was attenuated by current BMI (interaction HR 0.80, 95% CI 0.65-0.99) per 5 unit increase in BMI. There was little evidence of an interaction between MHT use, breast cancer risk and early and current BMI or with age of first pregnancy

From the open road to the high seas? Piracy, damnation and resistance in academic consumption of publishing

Armin Beverungen conducts research on how universities retain their charitable status in a market environment, and on the teaching of ethics in business schools. Steffen Böhm has a particular interest in the economics and management of sustainability. He has also founded an open access journal and an open access press, MayFlyBooks. Christopher Land works on artists and the management of their creativity