No abstract

No abstract

The Z‐source inverter was introduced to overcome shortcomings of voltage source inverter and current source inverter. In this paper, the concept of one switched‐inductor Z‐source inverter is extended to switched‐capacitor inductor ZSI with an impedance network. In the proposed inverter, capacitors are used instead of the side diodes of the one switched inductor Z‐source inverter. The proposed inverter has a higher boost factor compared to One SL‐ZSI and quasi‐ZSI. Also, it has lower voltage stress compared to similar inverters. The proposed inverter can be extended to n cases in cascade form. The components used in the proposed topology are lower than the SL‐ZSI. The analysis, derivation of boost factor, capacitor voltages, diode voltages, and switch voltages stress of the proposed inverter topology are carried out and are compared with the similar inverters. The advantages of the proposed structure are verified through simulation and implementation. The simulation is performed in MATLAB/SIMULINK.

Two structures are proposed based on the quasi Z‐source inverter (qZSI), which can significantly raise the output voltage in applications, including photovoltaic and fuel cells, in which the input voltage is low. The proposed inverters provide a continuous input current and reduce the voltage stress on capacitor. Besides, the proposed switched‐capacitor‐inductor qZSI (SCL‐qZSI) can suppress inrush current at the start up moment as this current might damage the devices. The performance of the proposed structures is investigated at different operating modes, and the voltage equations are calculated. The voltage stress on switches, the voltage stress on capacitors, the voltage stress on diodes, and the current stress on inductor, as well as the average DC‐link current, the gain voltage (G), and the boost factor (B) of the proposed inverters, are analysed and derived. They are then compared with similar converters. To confirm the performance of the proposed converters, a laboratory sample of converters is made, which with output voltages, capacitors voltages, input and output current for the proposed converters. The DC‐link (Vi) voltage is 95 with boost factor 1.6 for SCL‐qZSI, and the DC‐link voltage is 216 with boost factor 3.6 for the enhance switched‐capacitor‐inductor qZSI (ESCL‐qZSI), which confirms the relationships obtained from the proposed converters. Also, the abbreviation for this paper is shown in table 1.

PR81 is a monoclonal antibody that binds with high affinity to MUC1, which is over expressed on breast and other tumors. The objective of this study was to compare the two labeling methods (direct and indirect radioiodination) for application of this antibody against MUC1 as a radioimmunotherapeutical agent.Monoclonal antibody (PR81) against the tandem repeat of the core protein (MUC1) was prepared, characterized, purified, and labeled with 131I using the direct (chloramin-T) and indirect (Fmoc-D-Tyr (tBu)-D-Tyr (tBu)-D-Lys (Boc)-OH (YYK) attached to N-hydroxysuccinimide as a linker between PR81 and 131I) methods. The immunoreactivity of 131I-PR81 and 131I-TP-PR81 complexes with MUC1 (the native protein), BSA-P20 (a 20 amino acid corresponding the tandem repeat of MUC1) and MCF7 cell line were performed by RIA. In vitro stability of 131I-PR81 and 131I-YYK-peptide-PR81 complexes in human serum was determined by thin layer chromatography (TLC). Cell toxicity and in vitro internalization studies were performed with the MCF7 cell line, and the tissue biodistribution of the 131I-PR81 and 131I- YYK-peptide -PR81 complexes was evaluated in normal BALB/c mice at 4, 24 and 48 hrs. The labeling efficiency was determined by measuring the percentage recovery of radioactivity in the final product relative to the initial activity in the shipment vial, was found to be 59.9% +/- 7.9% for direct and 50% +/- 3.2% for indirect methods. 131I-PR81 and 131I- YYK- peptide -PR81 complexes showed high immunoreactivity towards MUC1 protein, BSA-P20 and MCF7 cell line. In vitro stability of the labeled products in human serum which was measured by thin layer chromatography (TLC) was found to be more than 50% over 24 hr for 131I-PR81 and 70% for 131I- YYK-peptide -PR81 complexes. Cell toxicity and in vitro internalization studies showed that the 131I-PR81 and 131I- YYK-peptide -PR81 complexes inhibited 80% growth of the MCF7 cultured cell lines in vitro in a high concentration and up to 40% of the 131I-PR81 and 60% of the 131I- YYK-peptide -PR81 complexes internalized after 24 h. Biodistribution studies were performed in normal BALB/c mice at 4, 24 and 48 hrs post-injection. Thyroid and stomach levels from PR81 labeled with 131I- YYK-peptide were two- to three- fold less than those with directly labeled 131I-PR81, suggesting low recognition of its D-iodotyrosine residue by endogenous deiodinase. These results show that the indirect labeling was better than the indirect labeling and 131I- YYK-peptide -PR81 may be considered as a promising candidate for therapy of breast cancer.