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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.

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.)

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.

Purpose: A sensitive inverse relationship between plasma homocysteine concentration and folate status has been demonstrated. Although children with sickle cell anemia (SCA) are at potential risk for folate deficiency, plasma homocysteine levels have not been reported in such patients. Therefore, a study was designed to assess plasma homocysteine levels as a marker of folate status., Design: Plasma homocysteine concentrations were measured in 120 children with SCA (102 in steady state and 18 during an acute complication) who had never received supplemental folic acid. Folate status was directly assessed in 34 of these patients., Results: Plasma homocysteine levels in the patients with SCA and control subjects were similar. The mean value +/- 1 SD was 5.8+/-2.5 micromol/L (range, 1.6 to 14.1 micromol/L) in the patients with SCA and 6.1+/-2.7 micromol/L (range, 1.7 to 15.3 micromol/L) in 73 pediatric control subjects. In a subpopulation of the study group (34 children), simultaneous serum folate, red cell folate, and total homocysteine concentrations were also measured. Their serum folate and red cell folate concentrations were normal: 12.4+/-10.0 nmol/L (range, 1 to 42 nmol/L) and 604+/-374.7 nmol/L (range, 205 to 1741 nmol/L), respectively. There was no correlation of plasma homocysteine concentration with various clinical or laboratory measures or with red cell folate concentration., Conclusion: Folate stores in children with SCA not receiving folic acid supplements are adequate despite an underlying hemolytic anemia.