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Model predictive control (MPC) is a powerful and emerging control algorithm in the field of power converters and energy conversion systems. This paper proposes a model predictive algorithm to control the power flow between the high-voltage and low-voltage DC buses of a bidirectional isolated full-bridge DC–DC converter. The predictive control algorithm utilises the discrete nature of the power converters and predicts the future nature of the system, which are compared with the references to calculate the cost function. The switching state that minimises the cost function is selected for firing the converter in the next sampling time period. The proposed MPC bidirectional DC–DC converter is simulated with MATLAB/Simulink and further verified with a 2.5 kW experimental configuration. Both the simulation and experimental results confirm that the proposed MPC algorithm of the DC–DC converter reduces reactive power by avoiding the phase shift between primary and secondary sides of the high-frequency transformer and allow power transfer with unity power factor. Finally, an efficiency comparison is performed between the MPC and dual-phase-shift-based pulse-width modulation controlled DC–DC converter which ensures the effectiveness of the MPC controller. [ABSTRACT FROM PUBLISHER]

IgA nephropathy (IgAN) is the most common form of chronic glomerulonephritis with IgA deposits present mainly in the mesangial areas. We performed a 10-year retrospective case-control study of 71 patients with IgAN to evaluate the long-term effects and prognostic factors associated with tonsillectomy. Forty-one patients (19 males and 22 females) underwent tonsillectomy (Group A) and 30 patients (13 males and 17 females) did not (Group B). These patients were followed for more than 10 years after renal biopsy. The average age at initial renal biopsy was 29.78 years in Group A and 33.0 years in Group B. The average follow-up period was 13 years and 3 months in Group A, and 12 years and 7 months in Group B. Glomerular damage demonstrated on renal biopsy was more extensive in Group A than in Group B. Prognosis after 10 years of follow-up was compared between the two groups. The clinical remission rate was 24.4% in Group A and 13.3% in Group B, the stable renal function rate was 82.9% in Group A and 70.0% in Group B, and the renal survival rate was 95.1% in Group A and 73.3% in Group B. The renal survival rate in Group A was significantly higher than that in Group B ( p <0.05). Although evaluation of renal pathology based on renal biopsy was useful in predicting the long-term effects of tonsillectomy in IgAN patients, the results of tonsillar provocation tests were not. [ABSTRACT FROM AUTHOR]

The serum concentrations of three separate tumor markers, squamous cell carcinoma antigen (SCC Ag), carcinoembryonic antigen (CEA) and Cyfra 21-1 were clinically correlated in 86 randomly selected patients with squamous cell carcinoma involving the head and neck. Positive findings for each tumor marker were totalled and statistically analysed. The upper limits of normal for SCC Ag, CEA and Cyfra 21-1 were set at 1.5, 2.5 and 2.0 ng/ml, respectively. Positivity rates were 20.6% for SCC Ag, 14.0% for CEA and 41.7% for Cyfra 21-1. Elevated Cyfra 21-1 concentrations correlated somewhat with age, whereas elevated CEA levels correlated with the site of tumor involvement. Overall, Cyfra 21-1 appeared to be the most useful marker in head and neck squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

IgA nephropathy (IgAN) is a type of chronic glomerulonephritis characterized by IgA deposits mainly in the mesangial area. It does not have so favourable a prognosis as was initially thought. This nephropathy is one of the diseases affected by tonsillar focal infections, and there have been patients in whom tonsillectomy has been effective. In this study, 24 patients with IgAN were followed for more than 2 years after tonsillectomy and studied clinicopathologically. Remission of proteinuria was observed in 41.7% of the patients 6 months after surgery and in 50.0% 2 years after surgery. At 2 years after surgery, patients with minor and focal segmental renal lesions showed a significantly higher rate of remission of proteinuria than patients with diffuse renal lesions. There was no statistically significant difference between positive and negative patients in the rate of remission of proteinuria based on any parameter of the tonsillar provocation test at any time after surgery. [ABSTRACT FROM AUTHOR]