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Background: Mounting evidence suggests that mitochondrial dysfunction contributes to lupus nephritis (LN) pathogenesis. Mitochondrial pyruvate carrier 1 (MPC1) and mitochondrial pyruvate carrier 2 (MPC2) mediating pyruvate transport from the cytoplasm to the mitochondrial matrix, determines the cell survival and cellular energy supply. Here, we aimed to investigate the association of mitochondrial pyruvate carrier expression with the clinical and histological features in LN.Methods: Patients with biopsy-proven proliferative LN (class III and class IV, n=18) and membranous LN (class V, n=18) were included. Expression of MPC1 and MPC2 were examined by immunohistochemistry. MPC protein levels in the two groups were evaluated by the Student's t-test. Correlation analysis between MPC levels and clinicopathological features was performed by Spearman's rank correlation.Results: Both MPC1 and MPC2 were exclusively expressed in renal tubules of enrolled LN. Significantly lower MPC1 and MPC2 were observed in patients with proliferative LN compared to membranous LN. In addition, the MPC1 and MPC2 were negatively correlated with SLEDAI-2K score, renal function, and renal pathology activity index.Conclusion: Both MPC1 and MPC2 were localized in renal tubules, and decreased MPC content was more pronounced in proliferative LN than membranous LN. MPC levels were significantly correlated with renal functions and renal pathology activity. [ABSTRACT FROM AUTHOR]

Glomerular basement membrane (GBM) thickening is a typical and essential histopathological characteristic for the diagnosis of primary membranous nephropathy (PMN). The present study aimed to explore the relationship between GBM thickness and treatment response in PMN patients. A total of 128 patients with nephrotic syndrome concurrent with PMN were studied. The highest GBM thickness was measured from at least five glomerular capillary loops using an electron microscope, and the mean value was obtained. Patients were categorized into three groups according to the tertiles of GBM thickness as follows: Group 1 (GBM thickness ≤ 1100 nm, n = 48), Group 2 (1100 nm < GBM thickness ≤ 1300 nm, n = 40), Group 3 (GBM thickness >1300 nm, n = 40). Clinicopathological features and treatment response were compared among the three groups. The associations of GBM thickness with complete remission (CR) were assessed by Cox proportional hazard analyses and a cubic spline curve. During a median follow-up period of 25.80 months, 69 (53.9%) patients achieved CR. Kaplan–Meier analysis showed that the non-CR probability was significantly higher in the highest tertile of GBM thickness (p˂0.001). Univariate Cox proportional hazard analysis indicated that GBM thickness was associated with CR (HR per SD 0.617, 95% CI [0.471–0.809], p˂0.001). After adjusting for age, duration of PMN, estimated glomerular filtration rate (eGFR), urinary protein excretion, grade of C3 deposition, and titer of serum anti-phospholipase A2 receptor (PLA2R) antibody, GBM thickness remained an independent predictor of CR (HR per SD 0.580, 95% CI [0.436–0.772], p˂0.001). Further multivariable-adjusted restricted cubic spline analysis confirmed a significant reverse linear association between GBM thickness and CR (p for nonlinear = 0.1261). GBM thickness is an independent risk factor of CR. PMN patients with an increased level of GBM thickening at diagnosis have a lower probability of achieving CR. [ABSTRACT FROM AUTHOR]

One of the main obstacles to the robust optimization for permanent magnet machines is the high computational burden, which is mainly caused by the robustness evaluation process considering the manufacturing uncertainties. In this paper, a sequential sampling Kriging model is adopted to estimate the design robustness, and the problem of high-dimensional variables for the surrogate model due to uncertainties is avoided through adopting the worst-case based approach. To further reduce the number of finite element analyses (FEA) required for constructing a metamodel, a multi-points sequential sampling process with a two-step optimization oriented surrogate model updating algorithm is proposed. Compared with the FEA directly based robust optimization in previous work, similar Pareto Fronts are achieved by adopting the meta-model proposed algorithm but the overall run time reduced by 75%. In the end, an optimization problem for a 1.2 kW motor is considered by applying the proposed algorithm, and two prototypes with deliberately designed tolerances, imitating the worst-case scenarios in the real world, are manufactured. The worst-case torque ripple is reduced from 7.6% to 4.8% after optimizing, and this verifies the efficacy of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Objectives: Growing evidence demonstrated that vitamin D levels had been linked to type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD) in light of various extraskeletal effects. Therefore, the present study aimed to evaluate the association of 25-hydroxyvitamin D [25(OH)D] level with the clinicopathological features and CKD progression in T2DM. Methods: A total of 182 patients with T2DM with CKD stages 1 through 4 (G1–G4) were retrospectively included. Identification of the serum 25(OH)D level associated with CKD progression was executed by Kaplan–Meier survival analysis and Cox proportional hazards models. We further performed sensitivity analyses with a time-weighted average (TWA) of the serum 25(OH)D level in 75 participants to reinforce the findings. Results: The median serum 25(OH)D level was 26 (IQR, 14; 39) nmol/L in the study participants. Median follow-up time was 42 months, during which 70 (38%) patients confronted CKD progression. Cumulative kidney outcomes were significantly higher in the lowest tertile of the serum 25(OH)D level in Kaplan–Meier analyses (P < 0.001). Consistently, the analyses of Cox proportional hazards regression models indicated a significantly greater risk for CKD progression in the lowest tertile of the serum 25(OH)D level compared with the highest tertile of the serum 25(OH)D level (P = 0.03). These relationships remained robust with further sensitivity analysis of data with TWA of the serum 25(OH)D level, showing an independent association between lower TWA of the serum 25(OH)D level and an unfavorable renal outcome in patients with T2DM with CKD. Conclusions: Our findings demonstrated that patients with T2DM with a decreased 25(OH)D level had deteriorated renal function. Both lower levels of baseline and TWA of serum 25(OH)D were associated with an increased risk of CKD progression in patients with T2DM, which suggested that the long-term maintenance of optimal vitamin D levels from early in life might be associated with reduced future risk of CKD development in T2DM. [ABSTRACT FROM AUTHOR]

Conventionally, the small mean and variance of peak-to-peak cogging torque of permanent magnet (PM) machines considering manufacturing uncertainties can be achieved by a robust design or by reducing the uncertainties range. However, the consequent compromise of other design objectives or the increase in the manufacturing costs are frequently inevitable. In this paper, the combination sequence of the uncertainties is highlighted and implemented to achieve a stable performance even for a non-robust design without increasing the cost too much. A PM assembling approach is proposed to mitigate the influences of PM uncertainties on cogging torque by means of combining the uncertainties in a particular sequence, where the effects of uncertainties would counteract each other. Both the singular type of PM uncertainties and the combined ones are considered in the assembling approach. Furthermore, the proposed approach is verified by comparing the cogging torque performance with PM randomly assembled models, where several hundreds of models featuring different uncertainties are calculated through the finite element method. The proposed approach is discussed, particularly for the application of mass production and a small amount of prototypes. Two prototypes with different PM assembling sequences are fabricated and further verify the effectiveness of the proposed PM assembling approach. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous motor (PMSM) possesses the advantages of low power loss, high power density and high torque density and, hence, has achieved broad applications in both industrial drives and home appliances. With the increasing demands for high power density, the PMSM often operates at high speed and high frequency, leading to high power loss and temperature rise. Consequently, proper consideration of power loss, including the core loss, has attracted much attention for the modelling, designing, controlling and optimizing of PMSMs. However, the widely used equivalent circuit model, capable of providing good analysis results with fast calculation, often ignores the core loss, which may lead to unsatisfactory motor performance. This paper aims to investigate the development of equivalent circuit models, with predictable core loss for PMSMs, and proposes novel equivalent circuit models, which improve the core loss prediction accuracy in the load conditions. Some thoughts about the further improvement of the models are proposed and discussed. [ABSTRACT FROM AUTHOR]

To improve the torque accuracy for open-end winding permanent magnet synchronous motor (OEW-PMSM) with common dc bus, it is necessary to eliminate the zero-sequence torque (ZST) caused by zero-sequence current (ZSC) and the third back electromotive force. But the third flux linkage mismatch can enlarge ZSC which causes torque ripple. To deal with the above problem, firstly, a q-axis current injection method combined with deadbeat predictive current control (DPCC) is adopted to inject an extra current into the reference q-axis current. The extra torque generated by this injected current can compensate for ZST. Secondly, to ensure the accuracy of the q-axis injected current, a parameter identification method based on recursive least square (RLS) algorithm with forgetting factor is presented to identify the third flux linkage accurately. The identification value can reduce ZSC and torque ripple under different working conditions. And the accurate q-axis injected current can be obtained to counteract ZST and output accurate torque. Finally, three methods are comparatively analyzed in this paper, namely the traditional DPCC method, the DPCC method with q-axis current injection and the proposed DPCC method based on RLS with forgetting factor. The simulation and experimental results verify the effectiveness of the proposed DPCC method. [ABSTRACT FROM AUTHOR]

Altered volcanic ash beds in the Middle Jurassic Temple Cap and Carmel Formations in southwestern Utah record a pulse of active arc-related volcanism between 166 and 171 Ma. A second pulse between 148 and 155 Ma has previously been documented in the Upper Jurassic Morrison Formation. Volcanic and volcaniclastic rocks of these same ages have also been identified closer to or within the arc in California in the Inyo Mountains, the Cowhole Mountains, the Palen Mountains, and the central Mojave Desert. The upper part of the volcaniclastic Mount Wrightson Formation and the strata of Cobre Ridge in southern Arizona are ca. 170 Ma in age and appear to be time correlative with the Middle Jurassic formations in southwestern Utah. The altered ash beds found in the Temple Cap and Carmel Formations typically contain phenocrysts of sanidine, quartz, biotite, apatite, zircon, and titanite. Plagioclase was likely present originally in all of the ashes, but was removed by alteration and is now found only in the Temple Cap red beds. Quartz and sanidine are absent in two crystal-poor ash beds that contain two pyroxenes, hornblende, and biotite. Although major and trace element concentrations in the ash beds have been substantially modified, compositions of relict phenocrysts reveal that the magmas were calc-alkaline rhyolites to andesites. Two-pyroxene, two-feldspar, biotite, and biotite-apatite thermometers suggest that crystallization occurred at temperatures ranging from 740 to 910 [degrees] C. Hornblende geobarometry yields pressures of 1-2 kilobars for the two ash beds that contain the appropriate buffer assemblage. The mafic silicates all have moderately high Mg/Fe ratios. This fact, combined with the presence of hornblende, biotite, and titanite, suggests that the phenocrysts crystallized at high oxygen fugacities similar to those of the granites of the batholiths of California. The ash probably erupted from a low-lying arc cut by strike-slip faults in what is now southern California and western Nevada. Major Jurassic unconformities occur near or within the ash-bearing formations in southwestern Utah. Laser-fusion single-crystal [sup.40]Ar/[sup.39]Ar measurements have defined the ages of the unconformities and the associated volcanism. The age of the J-1 unconformity, found at the base of the Temple Cap Formation in southwestern Utah, is older than ca. 170.5 Ma. The J-2 unconformity, which lies between the Temple Cap and Carmel Formations, formed between ca. 169 and 168 Ma. The origin of these unconformities is still unclear, but may be related to the Middle Jurassic pulse of magmatism and the oblique plate convergence along the western margin of North America. The age range of ash beds in the Carmel Formation between 166.3 and 168.0 [+ or -] ~0.5 Ma is consistent with a Bajocian-Bathonian boundary of ca. 166 Ma. Keywords: Carmel Formation, geochronology, Jurassic, Temple Cap Formation, volcanism.

Torque ripple reduction has become an active research area for permanent magnet synchronous machine (PMSM) drives. This paper presents a novel torque ripple reduction method based on harmonic current control. In the proposed method, the optimal harmonic current solution based on the torque ripple model with minimum stator resistive loss is derived in the rotor reference frame (RRF). The optimal harmonic currents are injected by the proposed harmonic current controller (HCC), wherein the magnitude of harmonic currents are defined as controller variables. To estimate the harmonic currents, the proposed method also utilizes the least mean square (LMS) based adaptive filter (AF), wherein the coefficients are defined as feedback to the proposed HCC. The proposed methodology is demonstrated using both simulations and experiments and is verified to reduce torque ripples of PMSM drives over a wide range of speeds. [ABSTRACT FROM AUTHOR]

Deadbeat predictive current control (DPCC) can predict motor behavior based on SPMSM model. However, during the operation of motor system, motor parameters (such as stator inductance and flux linkage) vary frequently according to different working conditions, which may lead to controller parameter mismatch, causing current harmonic content to increase and efficiency to decrease. In order to solve these problems caused by parameter variation, first, this paper proposes a current prediction error model by considering uncertainties of model parameters. Second, stator inductance and flux linkage are decoupled based on current prediction error model, which can reduce the interaction between parameters. Finally, the Kalman Filter (KF) algorithm is presented to filter the decoupled parameters. It is shown that the stator inductance and flux linkage can be identified accurately and the complexity of computation can be simplified. The traditional DPCC method, Extended Kalman Filter (EKF) based DPCC method and the proposed DPCC method are comparatively analyzed in this paper. Simulation and experiment indicate that the proposed parameter decoupling identification method can effectively reduce current harmonic content, current fluctuation and current tracking errors caused by parameter mismatch. [ABSTRACT FROM AUTHOR]

This article discusses a method to consider the effects of the manufacturing uncertainties on the additional cogging torque harmonics. With this method, the sensitivity analysis can be incorporated into the design stage instead of just checking it afterwards. With the authors’ previous work of the worst-uncertain-combination-analysis (WUCA) method, several design parameters and their effects on the additional cogging torque harmonics under uncertainties are discussed. It is demonstrated that a design with inherent robustness can be obtained through the proper selection of pole-arc coefficient and slot-opening width. In addition, a sensitivity index is proposed to estimate the effects of parameter uncertainties on torque harmonics. Some suggestions on improving the design robustness are consequently provided from the aspects of tolerances control and parameter design. The deductions are verified through finite element analysis (FEA) on different pole/slot configurations. [ABSTRACT FROM AUTHOR]

The current study aimed to assess the dietary salt intake in patients with CKD in Jiangsu province and investigate the relationship of urinary sodium excretion with blood pressure. A total of 800 patients with CKD stages 1–4 were recruited. All enrolled patients were asked to collect complete 24‐h urine specimen. At the same time, patient's demographic and laboratory data were recorded. The mean age was 47.45 ± 15.25 years old, including 423 men and 377 women. There was no significant difference in urinary sodium excretion among different stages of CKD (p =.748). This study revealed that the median urinary sodium excretion of all patients was 127.20 mmol/d (IQR 91.03–172.06), corresponding to a salt intake of 7.4 g/d. Among them, only 167 (20.9%) cases had salt intake <5 g/d. Moreover, urinary sodium excretion in overweight group and obese group was higher than that in normal weight group (p =.001, p ˂.001). Likewise, urinary sodium excretion in men was higher than that in women (p ˂.001). Spearman correlation analysis indicated that urinary sodium excretion positively correlated with urinary protein excretion (r =.178, p ˂.001), SBP (r =.109, p =.002), and DBP (r =.086, p =.015). After adjusting for age, gender, BMI, eGFR, urinary protein excretion, and history of taking antihypertensive drug, multivariate linear regression demonstrated that higher level of urinary sodium excretion associated with increased level of SBP, DBP, and MAP (β = 0.020, p =.049; β = 0.015, p =.040; β = 0.016, p =.025, respectively). In conclusion, the dietary salt intake in CKD patients, especially in male, overweight and obese subjects, remains high in Jiangsu province. It is vital to decline salt intake to control blood pressure in Jiangsu patients with CKD. [ABSTRACT FROM AUTHOR]

Over decades, substantial progress has been achieved in understanding the pathogenesis of proteinuria in diabetic kidney disease (DKD), biomarkers for DKD screening, diagnosis, and prognosis, as well as novel hypoglycemia agents in clinical trials, thereby rendering more attention focused on the role of renal tubules in DKD. Previous studies have demonstrated that morphological and functional changes in renal tubules are highly involved in the occurrence and development of DKD. Novel tubular biomarkers have shown some clinical importance. However, there are many challenges to transition into personalized diagnosis and guidance for individual therapy in clinical practice. Large-scale clinical trials suggested the clinical relevance of increased proximal reabsorption and hyperfiltration by sodium-glucose cotransporter-2 (SGLT2) to improve renal outcomes in patients with diabetes, further promoting the emergence of renal tubulocentric research. Therefore, this review summarized the recent progress in the pathophysiology associated with involved mechanisms of renal tubules, potential tubular biomarkers with clinical application, and renal tubular factors in DKD management. The mechanism of kidney protection and impressive results from clinical trials of SGLT2 inhibitors were summarized and discussed, offering a comprehensive update on therapeutic strategies targeting renal tubules. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous machines (PMSMs) are widely used owing to high power density, high efficiency, etc. Core losses account for a significant component of the total loss in PMSMs beside winding losses. Therefore, it is necessary to consider core losses when designing PMSMs according to actual research applications. In this paper, taking four typical rotor structures (surface-mounted, embedded, "—" shape, "V" shape) as examples, an analysis method is proposed to predict the influence of different rotor structures on core loss of PMSMs. In the case of the same stator and winding structures, due to the influence of the rotor structure on the magnetic circuit, the corresponding variation law of the magnetic field in the stator core is studied. This method analyzes the radial and tangential components of magnetic flux density vector of the 4 representative points (stator tooth tip, middle tooth and yoke part), and then evaluates the entire core loss through finite element analysis results. In order to verify the method, a prototype was manufactured. The experimental results show good performance of the proposed method of this paper. It provides reference for selecting the appropriate rotor structure and designing the corresponding PMSM according to different specification. [ABSTRACT FROM AUTHOR]

The two‐voltage‐vector (2VV) model predictive torque control (MPTC) has been widely discussed and compared to the conventional single‐voltage‐vector (1VV) MPTC in permanent magnet synchronous motor drive applications, where it was shown to have quick response and low torque ripple. An improved 2VV‐MPTC is set forth based on extended control set. In the proposed approach, the reference voltage vector is calculated using the established torque and flux deadbeat control and optimal calculation of the duty cycles. Moreover, to further improve the torque performance, the proposed algorithm is extended to three‐voltage vector (3VV), which is shown to achieve even better performance. Experimental results demonstrate that the proposed 2VV and 3VV‐MPTC algorithms have better computation efficiency and can significantly reduce torque ripple compared to the previous methods. [ABSTRACT FROM AUTHOR]

To improve the performance of open-winding permanent magnet synchronous motors (OW-PMSMs) with a common dc bus, a novel control method that can simultaneously eliminate parameter mismatch in the d-axis, q-axis, and zero-sequence loop (ZSL) is proposed. First, the parameter mismatches are analyzed. Second, an extended state observer (ESO), which can predict the current in the next instant and the disturbance caused by parameter mismatch, is established. By combining the ESO and the deadbeat predictive current control (DPCC) in the d-axis and q-axis, replacing the sampled current in the DPCC with the predictive current in the ESO, and considering predictive disturbance as a voltage reference feedforward compensation, one-step delay and the disturbance caused by parameter mismatch are addressed. Then, in the ZSL, the predicted zero-sequence disturbance is considered as a compensation for the reference zero-sequence voltage (ZSV). The ZSV is obtained using the zero-voltage vector redistribution strategy in alternate subhexagonal center pulsewidth modulation strategy. The proposed method enhances the robustness of OW-PMSM, against parameter mismatch in the d-axis, q-axis, or ZSL. To verify the effectiveness of the proposed method, simulation and experimental results obtained using the traditional DPCC method and the ESO+DPCC method are presented herein. [ABSTRACT FROM AUTHOR]

This paper proposes a computationally efficient approach for mapping permanent magnet (PM) power loss in permanent magnet synchronous machines (PMSMs). The PM loss mapping method here uses time-step finite element analysis (FEA) to determine the function parameters representing the loss variation with speed (frequency), amplitude modulation ratio, carrier ratio, and stator current and is suitable for rapid evaluation of machine performance over the entire torque–speed envelope. The PM loss can be accurately mapped across the full operational envelope, including the field-weakened mode. The loss mapping procedure takes into account the equivalent resistivity of axial segmentation of the PM array calculated by three-dimensional (3-D) FEA. The effect of temperature on the PM loss is also considered. The proposed methodology is validated on two surface-mounted PMSM designs. The results of the loss mapping procedure are consistent with those from direct 3-D finite element prediction and experimental results of PM power loss at each operating point of the machine. [ABSTRACT FROM AUTHOR]

Finite-set model predictive current control (FS-MPCC) has been employed for machine drives owing to the good dynamic performance. Sensitivity to parameter variation is one of the main barriers to its widespread application. To overcome this barrier, this article proposes an improved FS-MPCC for surfaced permanent magnet synchronous machines (SPMSMs). The contribution of this article is developing a novel current update mechanism, where the variation of resistance, rotor flux linkage, and inductance is considered, in which a modified coordinate system that contains a stationary and rotary axis frame is introduced. In this case, the predicted parameter can be obtained more accurately based on this mechanism, which can suppress the disturbances caused by model parameter mismatch. In addition, SPMSM parameter mismatch effect on FS-MPCC performance is analyzed in this article, which testifies that resistance mismatch influence on current prediction error can be neglected in practical system. The proposed FS-MPCC is validated and compared with different state-of-the-art methods. Improvement of the proposed control strategy is validated by means of experimental results on a 2-kW test rig. [ABSTRACT FROM AUTHOR]

One of the main obstacles to applying the robust optimization for the permanent magnet motors is the high computational burden, which is mainly caused by the robustness evaluation considering the manufacturing uncertainties. In this article, efforts are made to speed up the process of robust optimization, from the aspects of reducing the computational cost, and avoiding the computing resources being wasted. Firstly, several widely used methods, aiming to identify the worst-case performance under uncertainties, are examined, and compared. And the efficient worst-uncertain-combination-analysis (WUCA) method is consequently adopted to significantly reduce the computational cost of robustness evaluation. From another aspect, the parameter rounding (PR) operation is inevitable due to the constraint of manufacturing accuracy, but its adverse effects on the optimization are often ignored. It is found that parts of the computing resources might be wasted during the optimization. A new PR during the calculation (PRDC) method is proposed, and incorporated into the process of robust optimization. Compared with the conventional one, similar results can be achieved with the computational time reduced by approximately $\text{11}\%$ in the PRDC modified robust optimization. [ABSTRACT FROM AUTHOR]

Permanent-magnet (PM) motors have been widely used in industrial applications and automobiles. However, owing to the design tolerances, manufacturing uncertainties, and material inconsistency, deviations from the ideal motor inevitably occur with parasitic effects, such as additional cogging torque and vibration. One of the most significant obstacles for evaluating these uncertainties is the large computational burden caused by the countless uncertain combinations, which must be computed via the finite-element method (FEM). Herein, a worst-uncertain-combination-analyze (WUCA) method is proposed to significantly reduce the computational cost. A widely used analytical method is modified to identify the origin of additional cogging-torque harmonics caused by uncertainties. Different types of uncertainties for the surface-mounted PM machine and interior PM machine can be analyzed simultaneously. With the WUCA method, the worst-case combinations can be confirmed theoretically; thus, FEM calculations for only a few combinations of uncertainties are required, rather than thousands. Compared with the widely adopted design of experiments based uncertain combining methods, the worst-case cogging torque obtained from the WUCA is higher. FEM verification of different pole/slot configurations revealed that the WUCA method was a general and effective method for quickly estimating the worst-case cogging torque under manufacturing uncertainties. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous machines (PMSMs) are widely used in electric vehicles due to their high power density, high efficiency, etc. Core losses account for a significant component of the total loss in PMSMs. Therefore, it is necessary to carefully consider it when designing PMSMs according to actual scientific research project applications. This paper extracts the characteristic operating points of the PMSMs under different operating conditions at different speeds. Then a harmonic analysis of air-gap flux density, phase current, core loss was completed, and detailed comparative analysis was performed. A novel method for comprehensively analyzing the stator core loss of PMSMs for vehicles is proposed, which reveals the law of the core loss of the PMSM under Maximum-Torque-Per-Ampere (MTPA) and Space Vector Pulse Width Modulation (SVPWM). The method was verified by a prototype experiment where the actual core loss of PMSMs was measured to verify the correctness of the method. This research provides a reference for accurately predicting core loss during the forward design of PMSMs and completing core loss evaluation for existing PMSMs. [ABSTRACT FROM AUTHOR]

Objectives: As accumulating data supporting the potential role of the complement system in the pathogenesis of diabetic kidney disease (DKD), the present study aimed to explore the association of glomerular complement C4c deposition with the baseline clinicopathological characteristics and the prognosis of DKD in type 2 diabetes (T2DM) patients. Methods: A total of 79 T2DM patients with biopsy-proven DKD were enrolled. Clinicopathological features and renal outcomes were compared between groups divided by the glomerular C4c deposition patterns and median values of serum C4. Renal outcomes were defined by doubling of serum creatinine level or progression to end-stage renal disease (ESRD). A Cox proportional hazards model was employed to identify the risk factors associated with renal events. Results: Patients with glomerular C4c deposition had worse renal insufficiency than those without C4c deposits, along with higher 24-h urinary protein, triglyceride, but lower serum albumin and higher interstitial inflammation score. Besides, serum C4 levels positively correlated with urinary protein and serum C3 levels. During 21.85 ± 16.32 months of follow-up, Kaplan-Meier curve analysis showed significantly faster deterioration of renal function for patients with positive glomerular C4c deposition as well as higher levels of serum C4. More specifically, more than 50% of the patients with glomerular C4c had co-deposition of C3c or C1q, and patients with glomerular complement complex of C4c and one or two of C3/C1q deposition had more severe proteinuria and a higher rate of DKD progression than those with negative C4c deposits. The univariate Cox regression indicated that factors of combined serum and glomerular C4, urinary protein, serum creatinine, serum C3, combined glomerular C4c and IgM and interstitial inflammation were associated with an increased risk of DKD, but only glomerular C4c intensity (HR 1.584, 95% CI [1.001, 2.508], p = 0.0497), as well as baseline age and diabetic neuropathy, were independent risk factors for renal survival by the multivariate Cox analysis. Conclusions: Glomerular C4c deposition was associated with deteriorated renal function and outcomes in patients with T2DKD. Glomerular C4c deposition was an independent risk factor for DKD progression. [ABSTRACT FROM AUTHOR]

Conventional finite-control set model predictive current control predicts the motor behavior for every switching state and selects the voltage vector that can minimize the cost functions as an optimum voltage vector. To get rid of the model parameter dependency, a finite-control set nonparametric predictive current control (NPCC) was proposed before, which can predict future current behavior using the measured data instead of initial model parameters. However, one of the main issues that are limiting the current and torque ripple performance is a stagnant current update mechanism. To overcome this issue, this article proposes a novel current update mechanism that based on two most recent current variations to reconstruct the permanent magnet synchronous machine model. The proposed nonparametric predictive current control based on the current update mechanism can effectively reduce the torque ripple and enhance current performance in contrast to NPCC. Experiment results are demonstrated to verify the effectiveness of the proposed method under different operating conditions. [ABSTRACT FROM AUTHOR]

Background: Tacrolimus (TAC) is beneficial for patients with idiopathic membranous nephropathy (IMN). It has a narrow therapeutic concentration range and many factors influence TAC blood concentration. CYP3A5 is the most important enzyme in TAC metabolism. The aim of this study was to analyze the effects of CYP3A5 gene polymorphisms on the efficacy and safety of TAC in IMN patients. Patients and Methods: Patients with IMN who received oral TAC (0.05– 0.075mg/kg/day) combined with prednisone (0.5mg/kg/day) from March 2016 to October 2018 were included. The data of clinical characteristics, therapeutic drugs and adverse reactions of patients were collected at baseline and during 24 weeks of treatment. Patients were divided into two groups according to different CYP3A5 genetic polymorphisms. The significant differences in the efficacy and side effects between the two groups were analyzed. Results: A total of 76 patients who completed follow-up were divided into CYP3A5 nonexpresser (CYP3A5*3/*3) group and CYP3A5 expresser (CYP3A5 *1/*3) group. The significant association between the CYP3A5 phenotype and TAC metabolism was observed. A total of 43 case-times patients exhibited adverse effects. The infection rate in CYP3A5 nonexpresser group (21.95%) was remarkably higher than the rate in CYP3A5 expresser group (5.71%). Blood concentration and C0/D levels were risk factors for adverse events through logistic regression analysis. There was no statistical difference between the study groups with respect to the efficacy. Conclusion: Our results demonstrated that CYP3A5 polymorphisms had important guiding roles in the treatment of IMN with tacrolimus. CYP3A5 expressers required higher daily doses of TAC to achieve the target drug concentration, but with fewer side effects. CYP3A5 genetic polymorphism might be used for TAC dosing adjustment to optimize the treatment for patients with IMN. [ABSTRACT FROM AUTHOR]

In order to suppress the torque ripple of an open-end winding permanent-magnet synchronous machine (OEW-PMSM), a q-axis current injection method is typically employed but the disturbances caused by the third flux linkage parameter mismatch can augment the torque ripple. To solve this problem, in this paper, first, a zero-sequence current (ZSC) and zero-sequence back-EMF observer (ZCBO) are proposed based on an adaptive sliding mode control, which is able to simultaneously estimate ZSC and zero-sequence back EMF under varying conditions. Based on this ZCBO, the estimated ZSC and zero-sequence back EMF could compensate for the one-step control delay and suppress the aforementioned disturbances. Second, although central hexagon modulation is employed in the predictive current control (PCC) scheme, zero-sequence voltage (ZSV) still exists in the zero-sequence path due to the dead time of the inverter, affecting the predictive accuracy of the ZCBO. To accurately establish the ZCBO, the ZSV caused by the dead time of the inverter is considered in the ZCBO. Finally, a comparative study of two types of methods is presented, and simulations established by MATLAB software and experimental confirmations are carried out to verify the effectiveness of the proposed PCC scheme in this paper. [ABSTRACT FROM AUTHOR]

Model predictive current control (MPCC) can predict future motor behavior according to a motor model. In practice, however, motor parameters will vary at run time, and the parameter mismatch disturbances caused by the variation in motor parameters will deteriorate the MPCC performance. To suppress the parameter mismatch disturbances effectively, this paper proposes a modified MPCC with a current variation update mechanism. In contrast with the traditional current prediction equation that contains crude model parameters, the modified current prediction equation contains only measured information, taking advantage of the proposed current variation update mechanism, which can update the modified prediction equation within each sampling period. A simulation established by MATLAB software indicates that the proposed method can effectively suppress the parameter mismatch disturbances. Experiments are carried out to verify the correctness of the proposed method. [ABSTRACT FROM AUTHOR]

In an open-end winding permanent magnet synchronous machines drive with single dc voltage source, zero-sequence current (ZSC) can lead to a high current stress of power modules and loss of motor. Therefore, some modulation strategies have been employed to alleviate ZSC by suppressing zero-sequence voltage (ZSV). However, ZSC still exists in the system because ZSV can also be generated by other nonlinear factors of inverter such as the dead time of system. In addition, zero-sequence back electromotive force in the zero-sequence path can also enlarge torque ripple and ZSC. In order to deal with above problems, first, this paper proposes a full-order adaptive zero-sequence observer to estimate future ZSC and ZSV, which are able to compensate one-step control delay. Second, to achieve the maximum voltage dc bus utilization, this paper proposes a novel deadbeat predictive current control (DPCC) scheme with alternate sub-hexagonal center pulsewidth modulation strategy to suppress ZSC and torque ripple simultaneously. Finally, this paper presents a comparative study of two types of methods, namely traditional DPCC scheme and the proposed DPCC scheme. Simulation and experimental results are demonstrated to verify the effectiveness of the proposed DPCC scheme. [ABSTRACT FROM AUTHOR]