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Hydroxyurea (HU) is an effective but underused disease-modifying therapy for patients with sickle cell anaemia (SCA). EMBRACE SCD, a sickle cell disease treatment demonstration project, aimed to improve access to HU by increasing prescription (Rx) rates by at least 10% from baseline in children with SCA.The Model for Improvement was used as the quality improvement framework. HU Rx was assessed from clinical databases in three paediatric haematology centres. Children aged 9 months-18 years with SCA not on chronic transfusions were eligible for HU treatment. The health belief model was the conceptual framework to discuss with patients and promote HU acceptance. A visual aid showing erythrocytes under the effect of HU and the American Society of Hematology HU brochure were used as educational tools. At least 6 months after offering HU, a Barrier Assessment Questionnaire was given to assess reasons for HU acceptance and refusals. If HU was declined, the providers discussed with family again. We conducted chart audits to find missed opportunities to prescribe HU as one plan-do-study-act cycle.At initial measurement, 50.2% of 524 eligible patients had HU prescribed. During the testing and initial implementation phase, the mean performance after 10 data points was 53%. After 2 years, the mean performance was 59%, achieving an 11% increase in mean performance and a 29% increase from initial to the last measurement (64.8% HU Rx). During a 15-month period, 32.1% (N=168) of the eligible patients who were offered HU completed the barrier questionnaire with 19% (N=32) refusing HU, mostly based on not perceiving enough severity of their children's SCA or fearing side effects.Reviewing patient charts for missed opportunity of offering HU with feedback and evaluating the reasons of declining HU via a questionnaire were key components in increasing HU Rx in our population., Competing Interests: Competing interests: ELJC and IO report employment by Forma Therapeutics, now part of Novo Nordisk. IO also reports funding by Patient-Centered Outcomes Research Institute (PCORI) for another study., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Byline: H. Rodriguez-Cortes, C.N. Hadjicostis, A.M. Stankovic Induction motors are the dominant components in industrial processes involving electromechanical energy conversion. Safety, reliability and efficiency are major concerns in modern induction motor applications. Since detecting faults on time could avoid costly unscheduled shutdowns, in recent years there has been an increased interest in induction motor fault detection and diagnosis. In this paper, we propose monitoring schemes to solve fault detection problems of induction motors. We begin with a monitoring scheme to detect detuning operation in Indirect Field Oriented Control (IFOC) driven induction motors. Secondly, we present a monitoring scheme to detect broken rotor bars on IFOC-driven induction motors. The proposed monitoring scheme does not rely on spectral methods; instead, it monitors a carefully selected induction motor state, using an online observer. The key to fault detection is the development of a simplified dynamic model of a squirrel cage induction motor with broken rotor bars. Numerical simulations validate both monitoring schemes.

Background: Adherence to long-term treatment is challenging. Deferasirox (DFX) is a daily oral iron chelator approved in the United States for transfusional iron overload., Procedures: Twenty-one subjects with sickle cell disease (mean age 13.8+/-4.2 y) received DFX 20 to 30 mg/kg daily for 1-year while on chronic blood transfusions. Good adherence to DFX was defined as > or =80% intake of prescribed dose. Adherence was assessed by monthly pill counts and calendars, and questionnaires at 1, 3, 6, and 12 months follow-up., Results: Fifteen of 21 subjects (71%) were adherent to DFX according to self-reports, with 83% of the patients being adherent at 1 month, 89% at 3 months, 65% at 6 months, and 78% at 12 months. We were only able to document continuous good adherence in 43% of patients by pill counts because of poor bottle return. The discrepancy between pill counts and self-reports may be related to over-reporting, with the real adherence being lower. Parental involvement with DFX administration (P=0.03) and age < or =16 years (P=0.0055) correlated with adherence. We could not detect a significant correlation between serum ferritin declines and adherence., Conclusion: Seventy-one percent of patients adhered to DFX according to questionnaire responses but only 43% did according to pill counts. Adherence was poorer in adolescents older than 16 years of age and in patients who had no parental supervision of medications.

Novel vertical take-off and landing advanced air mobility aircraft which are overactuated and transition between vertical and forward flight modes pose unique challenges for the design of safe and robust full-envelope fly-by-wire flight control systems. This paper presents a methodology for designing and optimizing a control system architecture for a tilt-wing urban air mobility concept. It features the total energy control system algorithm, which is extended to be applicable to hover and transitioning flight and explicit model following inner loops. Control system parameters are optimized using a genetic algorithm optimization scheme, subject to constraints on closed-loop dynamic stability and control response characteristics. Control system performance is demonstrated by simulation of lateral, longitudinal, and directional maneuvering for hover, transition, and forward flight conditions, followed by simulation of departure and arrival transitions while tracking a prescribed flightpath and speed profile in calm and turbulent air. The results demonstrate the effectiveness of the proposed control system architecture and the demonstrated optimization methodology. [ABSTRACT FROM AUTHOR]

As an extended application of unmanned aerial vehicle (UAV), the system of a quadrotor with suspended load has a good development prospect because of its flexible performance and stable structure. However, the suppressive swing of the load and the consequently swaying of the UAV may cause crashes during the flight transportation. In order to solve the above problems, this paper introduces a rope with elasticity and damping of the transportation system of quadrotor with suspended load, which reduces the swing of the load by increasing the dissipativity of the system, and establishes the dynamic model of the proposed system. Then a new adaptive controller with unknown mass parameter is designed based on energy analysis method. The stability of the closed-loop system is proved by Lyapunov method and LaSalle's invariance principle. Numerical simulation results show that the proposed adaptive controller can eliminate the effects of the uncertain mass, and the proposed system can reach the specified position rapidly and the swing of the load can converge quickly under the action of the controller, which avoids flight accidents. [ABSTRACT FROM AUTHOR]

Limited data regarding erythrocytapheresis in children, adolescents, and young adults have been published. The aim of this study was to evaluate erythrocytapheresis, either as a standalone therapy or in combination with iron chelation therapy, in children and young adults with hemoglobinopathies in whom current iron chelation therapy is not sufficient in decreasing the iron overload during management. We retrospectively analysed erythrocytapheresis in 19 patients with hemoglobinopathies in need of iron chelation therapy diagnosed with sickle cell disease (SCD) or β-thalassemia major. Patients were divided into (1) a case cohort who received erythrocytapheresis alone or in combination with iron chelation therapy and (2) a control cohort who received oral iron chelation therapy alone. Serum ferritin and haemoglobin levels were compared at five different time points over a one-year period. In the erythrocytapheresis cohort, there was a significant decrease in serum ferritin (p < 0.001). In the iron chelation therapy alone cohort, there was no significant decrease in serum ferritin over time (p = 0.156). Comparing the evolution of median serum ferritin between therapy with erythrocytapheresis and iron chelation therapy showed a statistically significant difference (p = 0.008). Patients with β-thalassemia major receiving erythrocytapheresis showed a greater reduction in serum ferritin compared to patients without (p = 0.036). A difference could not be shown between the erythrocytapheresis and iron chelation single therapies (p = 0.100). This study showed an overall significant reduction in serum ferritin in patients with hemoglobinopathies treated with erythrocytapheresis in addition to iron chelation. A clinical, although not statistical, trend of higher haemoglobin levels was maintained. Erythrocytapheresis in paediatric patients with β-thalassemia major was as effective in decreasing ferritin levels as in previously reported studies with SCD. Erythrocytapheresis is a promising therapy for treating and preventing transfusion-related iron overload. [ABSTRACT FROM AUTHOR]

This article deals with modelling and a flatness-based robust trajectory tracking scheme for a two degrees of freedom helicopter, which is subject to four types of tail rotor disturbances to validate the control scheme robustness. A mathematical model of the system, its differential flatness and a differential parametrization are obtained. The flat filtering control is designed for the system control with a partially known model, assuming the non-modelled dynamics and the external disturbances (specially the tail rotor ones) to be rejected by means of an extended state model (ultra-local model). Numerical and experimental assessments are carried out on a characterized prototype whose yaw angle (ψ), given by the z axis, is in free form, while the pitch angle (θ), which results from rotation about the y axis, is mechanically restricted. The proposed controller performance is tested through a set of experiments in trajectory tracking tasks with different disturbances in the tail rotor, showing robust behaviour for the different disturbances. Besides, a comparison study against a widely used controller of LQR type is carried out, in which the proposed controller achieves better results, as illustrated by a performance index. [ABSTRACT FROM AUTHOR]