Search

Considering the intrinsic defects of finite control set MPC (FCS-MPC), e.g., torque ripple and various harmonic frequencies, the modulated model predictive control (M2PC) has been regarded as a promising approach to achieve high performance of permanent magnet synchronous motor (PMSM) drives. However, the M2PC still faces non-minimum tracking error and unreasonable trajectory settings when rated-speed operation extends to the field-weakening (FW) region since the intervention of multiple constraints of voltage and current has to be taken into account. To address this problem, an M2PC-based scheme is proposed to realize the field-weakening operation with minimum tracking error and reasonable trajectory setting. Specifically, the equal proportion algorithm is replaced by an algebraical way for minimum tracking error in the over-modulation region; the predictive current error margin is used to preset the current trajectory in FW operation. Besides, the pre-triggering method is applied to reduce the control delay and eliminate the cumulative error, which improves the tolerance of parameter perturbation. Comparison results conducted on a Zynq7020-based PMSM setup validate the superiority of the proposed method regarding the capability of high-speed operation and high-dynamic performance.

The finite-control-set model predictive control (FCS-MPC) is an effective control method for permanent magnet synchronous motor (PMSM) drives with multiple constraints. However, it suffers from the trajectory deviation in the field-weakening region due to the model mismatch. In addition, the inherent discreteness of FCS-MPC further hinders the continuous prescribed trajectory in the field-weakening region. To address this problem, a field-weakening scheme with virtual voltage is studied to realize trajectory correction through the feedback mechanism. The concept of virtual voltage is proposed and constructed with continuous, excess, and perturbed components. The three components are extracted from the model characteristics, the predicted current error, and the disturbing current, which provide continuity, field-weakening trigger, and parametric immunity for the virtual voltage, respectively. Comparison experiments are conducted on the FPGA+ARM-based PMSM test rig to validate the dynamic performance and trajectory deviation immunity in the field-weakening region.

Background: Urosepsis is a life-threatening organ disease in which pathogenic microorganisms in the urine enter the blood through the vessels, causing an imbalance in the immune response to infection. The aim of this study was to elucidate the role of testicular orphan receptor 4 (TR4) in urosepsis. Methods: The role of TR4 in the progression and prognosis of urosepsis was confirmed by analyzing data from online databases and clinical human samples. To mimic urosepsis, we injected E. colibacteria into the renal pelvis of mice to create a urosepsis model. Hematoxylin and eosin staining was used to observe histopathological changes in urosepsis. The effects of the upregulation or downregulation of TR4 on macrophage pyroptosis were verified in vitro. Chromatin immunoprecipitation assay was used to verify the effect of TR4 on Gasdermin D (GSDMD) transcription. Results: TR4 was more highly expressed in the nonsurviving group than in the surviving group. Furthermore, overexpressing TR4 promoted inflammatory cytokine expression, and knocking down TR4 attenuated inflammatory cytokine expression. Mechanistically, TR4 promoted pyroptosis by regulating the expression of GSDMD in urosepsis. Furthermore, we also found that TR4 knockdown protected mice from urosepsis induced by the E. coli. Conclusions: TR4 functions as a key regulator of urosepsis by mediating pyroptosis, which regulates GSDMD expression. Targeting TR4 may be a potential strategy for urosepsis treatment.

Two similar enzymes with different biosynthetic function in one species have evolved to catalyze two distinct reactions. X-ray structures of both enzymes help reveal their most important differences. The Rauvolfiaalkaloid biosynthetic network harbors two O-glucosidases: raucaffricine glucosidase (RG), which hydrolyses raucaffricine to an intermediate downstream in the ajmaline pathway, and strictosidine glucosidase (SG), which operates upstream. RG converts strictosidine, the substrate of SG, but SG does not accept raucaffricine. Now elucidation of crystal structures of RG, inactive RG-E186Q mutant, and its complexes with ligands dihydro-raucaffricine and secologanin reveals that it is the “wider gate” of RG that allows strictosidine to enter the catalytic site, whereas the “slot-like” entrance of SG prohibits access by raucaffricine. Trp392 in RG and Trp388 in SG control the gate shape and acceptance of substrates. Ser390 directs the conformation of Trp392. 3D structures, supported by site-directed mutations and kinetic data of RG and SG, provide a structural and catalytic explanation of substrate specificity and deeper insights into O-glucosidase chemistry.

A method to detect DNA glycosylase activity is described. The substrate used was an oligodeoxyribonucleotide with a unique hypoxanthine base, but has general application to any DNA glycosylase or endonuclease. The oligodeoxyribonucleotide was labeled at the 5' end with ³²P and at the 3' end with a biotin linkage and annealed to a complementary oligodeoxyribonucleotide. The hypoxanthine base was excised in solution using the MPG protein, a human DNA glycosylase. Following cleavage of the phosphodiester linkage by NaOH, the oligodeoxyribonucleotide was attached to streptavidin-coated, paramagnetic beads. Binding of the labeled oligodeoxyribonucleotide to the beads was indicative of the kinetics of the reaction. As a control, half of the reaction products were loaded on to a denaturing polyacrylamide gel. Comparable values for steady-state kinetic constants were obtained using both methods. This nonelectrophoretic technique is a rapid assay of DNA glycosylase activity for both purified proteins and crude extracts. This method can be directly adapted for high-throughput techniques. Copyright 2001 Academic Press.

•SncRNAs contribute to the progress of renal cell carcinoma.•SncRNAs are promising biomarkers for diagnosis and prognosis of renal cell carcinoma.•Despite the potential of sncRNA-based cancer therapy, some obstacles remain, including several severe adverse effect.

•A short-type PGRP named Eco-PGRP-S was identified from grouper.•Eco-PGRP-S can bind with PGN and is inducible following PGN stimulation.•Zn2+-dependent amidase activity and antibacterial activity is observed for Eco-PGRP-S.•Eco-PGRP-S is mainly localized in cytoplasm and nucleus.•Eco-PGRP-S can elicit a significant activation of NF-κB promoter.

•The experiment is the first of its kind related to Nile tilapia on starvation and re-feeding.•The serum cortisol, AST and ALT after 14 days of starvation and decreased after 21 days of re-feeding.•The antioxidant gene expressions were up-regulated during starvation and down-regulated after re-feeding while leptin mRNA expression was down-regulated.•The relative abundance of the top five bacterial phyla in the intestinal of Nile tilapia (feeding, starvation and re-feeding groups) were Fusobacteria, Proteobacteria, Firmicutes, Bacteriodetes, and Actinobacteria.•The relative abundance of the top three intestinal bacterial genera of Nile tilapia (feeding, starvation and re-feeding groups) were Cetobacterium, Romboutsia, Plesiomonas, Bacteroides, and Clostridium senso stricto.

•The antioxidant enzyme activities were significantly increased during starvation and decreased during re-feeding.•The haematological indices were significantly increased after 14 days starvation and decreasing during re-feeding increased after 14 days starvation.•Blood glucose declined significantly after 14 days of starvation while PK and LDH increased significantly after 14 days of starvation.•Serum IgM and serum lysozyme indicated a significant response during starvation and declined after re-feeding.•Protease and Lipase were significantly decreased 21 days after 21 days of starvation while antiprotease increased after 21 days of starvation.