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This paper proposes the modulation and control of a three-to-six-phase matrix converter with an asymmetrical six-phase output. The matrix converter (MC) outputs consist of two sets of three-phase spatially shifted by 300, where the two sets have two isolated neutrals. The space vector approach is considered for the modeling and subsequent modulation of the three-to-six phase MC. The intelligent selection of voltage space vectors is made to synthesize the reference voltages and to obtain a sinusoidal output. The dwell times of selected voltage space vectors are adjusted in such a way that the effect of the second and the third auxiliary plane vectors (i.e., x1-y1, and x2-y2) are nullified. To achieve the maximum output voltage gain and to ensure that no reactive power is drawn from the utility supply, the input side power factor is maintained at unity. Nevertheless, the source side power factor is controllable. The modulation technique is implemented in dSPACE working in conjunction with a FPGA. Hardware results that validate the proposed control algorithm are discussed. [ABSTRACT FROM AUTHOR]

Background: The outcome of acute myeloid leukemia (AML) in low-middle-income countries (LMIC) is dismal due to delayed clinical presentation and infection-related complications. We aimed to analyze the outcome of patients with AML and the factors associated with its prognosis. Methods: A retrospective observational study was conducted at a tertiary care university hospital in North India from January 2015 to December 2019. Results: A total of 137 AML patients (median age 32 year (3–66 years) received intensive chemotherapy during study period. The median delay from diagnosis to treatment was 45 days (6–177 days). Among the 352 febrile neutropenia (FN) episodes analyzed, 175 (49.7%) were culture positive; Gram-negative multi-drug resistant organism (MDRO) sepsis during induction being 57.4% with 34.5% infections due to carbapenem-resistant Enterobacteriaceae (CRE) leading to a mortality rate of 14.6%. The median EFS and OS were 12.0 ± 1.57 (95% CI 8.91–15.08) and 15.0 ± 2.44 (95% CI 10.21–19.78) months respectively. Multivariable analysis revealed significant difference in median OS between favorable vs high risk AML groups (20.0 (95% CI: 12.50–27.49) vs 9.0 (95% CI: 2.99–15.01) months; p = 0.002); time from diagnosis to treatment (< 30 days vs ≥ 30 days; not reached vs 9.0 (95% CI: 6.81–11.18) months; p = 0.001), performance status (1 vs 2 vs 3; not reached vs 12.0 (95% CI: 10.32–13.67) vs 4.0 (95% CI:2.77–5.22); p = 0.001), and attainment of complete remission vs induction failure (not reached vs 6.0 (95% CI: 3.78–8.21); p = 0.002). Conclusion: Patient-related factors like delayed treatment initiation and high incidence of MDRO-associated sepsis are critical determinants of AML outcome in LMIC. [ABSTRACT FROM AUTHOR]

A letter to the editor on hydatid disease of the intestine is presented.