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Abstract With the evolution of renewable energies, many doubly fed induction generators (DFIGs) are being connected to the power grid, whose operation and grid‐connection stability have a major impact on the power grid. Currently, most studies focus on either modeling the mechanical–electrical section or the electrical‐grid section, and discussions have been limited to shaft oscillation or frequency coupling problems. In this study, a mechanical–electrical‐grid model of a DFIG was established to examine the impacts of wind speed and system control parameters on electrical damping and grid‐connection stability. The accuracy of the proposed model and validity of the analyses were verified using simulations. The following were observed: (1) In the case of changing wind speeds, the wind speed and the applied control model determine the shaft oscillation of DFIG, whereas the grid‐connected impedance on the rotor side is dependent on the wind speed. (2) At a constant wind speed, changes in control parameters under different control modes affect the dynamic characteristics of the drive train differently, whereas the grid‐connected impedance on the rotor side is primarily determined by the proportional gain of the inner/outer loop of the control system. The conclusions drawn from this study can further improve the safe and stable operation of DFIG wind power generation systems as well as their connection to the power grid.

Abstract To research the magnetic field and mechanical characteristics of the permanent magnet governor, the static magnetic field of the sector permanent magnet is analyzed by the molecular current method in the permanent magnet governor. The magnetic flux distribution is acquired at any spatial position. Comparing the analytical value with the simulation value, the results show that they are basically consistent. Based on the analytical formula, the influence of the radial position, radial length, thickness, and pole number on the magnetic induction intensity of the permanent magnet governor is studied. Thus, it provides the theoretical reference for the structural optimized design. At the same time, a test bench was set up to measure the magnetic induction intensity. The calculation and experimental results show that the magnetic induction strength of the permanent magnet is increased by 27.5%, the axial component of the air gap flux density is increased by 14.3%, and the permanent magnet material is reduced by 7.84%.

Abstract A high-power permanent magnet speed regulator is applied to a cooling water pump for conserving energy during the steel production in Magang (Group) Holding Co., Ltd. The designed setup of high-power permanent magnet speed regulator with a mobile base is shown in this manuscript, and the magnetic eddy under the different meshing area between driving and driven shafts has been simulated. And estimation indicates that the magnet speed regulator-controlled cooling water pump can save electric energy by 22%, about 1,756,400 kW·h per year, compared to the traditional valve-controlled pump, and the waste heat generated by this setup is below 5 ten-thousandths of the shaft power. Meanwhile, the permanent magnet speed regulator has a much lower vibration because of this non-contact way between the driving and driven shafts.

Interleaved Nx multilevel boost converter (Nx MBC) has the advantages of low current stress, high efficiency, and high voltage gain without extreme duty cycle. However, it is difficult to design a controller for interleaved Nx MBC due to the high order of state-space equations. A reduced order state-space averaged model of the interleaved Nx MBC is proposed to reduce the complexity of the model. For the case of constant power load (CPL), an adaptive sliding mode controller based on nonlinear disturbance observer is designed on the basis of its reduced order state-space averaged model. The nonlinear observer is used to estimate the output power and avoid sampling error caused by interference. In order to ensure the large signal stability of the system, an adaptive law is introduced into the sliding mode controller to suppress the chattering phenomenon. Simulation and experimental results show that the proposed control algorithm has good dynamic regulation characteristics when the CPL and input power supply are disturbed.

Aquaculture has experienced significant growth, contributing to resolving the global food crisis and delivering substantial economic benefits. Nevertheless, the uncontrolled expansion of aquaculture activities has led to an ecological crisis in offshore waters. This highlights the critical need for precise delineation and monitoring of aquaculture areas in these regions to ensure scientific management and sustainable development of coastal areas. In this article, we introduced an SRUNet model based on the Swin Transformer for accurately extracting offshore raft aquaculture areas using medium-resolution remote sensing images. Our SRUNet model combined the UNet model with the Swin Transformer block and the residual block to account for multiscale features, resulting in excellent extraction performance in diverse and complex sea areas. To evaluate the model, we selected four typical raft aquaculture areas and compared the SRUNet model with other comparative network models. Results revealed that the SRUNet model outperformed all other models, and the F1 Score and MIoU of the classification results were 86.52% and 87.22%, respectively. The model reduced the loss of feature information and misclassification of aquaculture areas, generating extraction effects that aligned closely with real aquaculture area shapes. Additionally, we tested the performance of each component of the SRUNet model. The results indicate that the SRUNet model exhibits strong robustness and effectively filters out irrelevant information. These results demonstrate the model's potential for large-scale extraction of offshore aquaculture areas.

Due to the non-linear and non-stationary nature of daily new 2019 coronavirus disease (COVID-19) case time series, existing prediction methods struggle to accurately forecast the number of daily new cases. To address this problem, a hybrid prediction framework is proposed in this study, which combines ensemble empirical mode decomposition (EEMD), fuzzy entropy (FE) reconstruction, and a CNN-LSTM-ATT hybrid network model. This new framework, named EEMD-FE-CNN-LSTM-ATT, is applied to predict the number of daily new COVID-19 cases. This study focuses on the daily new case dataset from the United States as the research subject to validate the feasibility of the proposed prediction framework. The results show that EEMD-FE-CNN-LSTM-ATT outperforms other baseline models in all evaluation metrics, demonstrating its efficacy in handling the non-linear and non-stationary epidemic time series. Furthermore, the generalizability of the proposed hybrid framework is validated on datasets from France and Russia. The proposed hybrid framework offers a new approach for predicting the COVID-19 pandemic, providing important technical support for future infectious disease forecasting.

Abstract Background The coexistence of primary hyperparathyroidism and papillary thyroid carcinoma (PTC) is common and may be associative with more aggressive PTC, with higher rates of extrathyroidal extension and multicentricity. However, it is unclear whether secondary hyperparathyroidism (SHPT) is associated with more invasive PTC in terms of morbidity, tumor pathological characteristics, and prognosis. The aim of this study was to evaluate the rate and tumor characteristics of PTC in patients with SHPT. Methods A total of 531 patients diagnosed with SHPT who underwent surgery from August 2013 to December 2018 at the First Affiliated Hospital of Zhejiang University were evaluated retrospectively. Patient demographics, surgical records, and follow-up information were recorded and analyzed. Control subjects were matched to the enrolled patients in a 1:4 ratio in terms of age, sex and pathological subtype. Results Among the 531 patients with SHPT who underwent surgery, 34 had coexisting PTC and PTC + SHPT (6.4%). The mean tumor diameter in the PTC + SHPT group was smaller than that in the PTC group (5.57 mm vs 9.00 mm, p

Alpha-fetoprotein producing gastric carcinomas (AFPGC) are rare and aggressive. Here, the authors profile AFPGC tumours using whole exome sequencing, and find amplifications in CCNE1 and ERBB2 that are associated with poor outcomes but are potential therapeutic targets, as shown in patient-derived xenografts.

The upstream of bioenergy industry has suffered from unreliable operations of granular biomass feedstocks in handling equipment. Computational modeling, including continuum-mechanics models and discrete-particle models, offers insightful understandings and predictive capabilities on the flow of milled biomass and can assist equipment design and optimization. This paper presents a benchmark study on the fidelity of the continuum and discrete modeling approaches for predicting granular biomass flow. We first introduce the constitutive law of the continuum-mechanics model and the contact law of the coarse-grained discrete-particle model, with model parameters calibrated against laboratory characterization tests of the milled loblolly pine. Three classical granular material flow systems (i.e., a lab-scale rotating drum, a pilot-scale hopper, and a full-scale inclined plane) are then simulated using the two models with the same initial and boundary conditions as the physical experiments. The close agreement of the numerical predictions with the experimental measurements on the hopper mass flow rate, the hopper critical outlet width, the material stopping thickness on the inclined plane, and the dynamic angle of repose, clearly indicates that the two methods can capture the critical flow behavior of granular biomass. The qualitative comparison shows that the continuum-mechanics model outperforms in parameterization of materials and wall friction, and large-scale systems, while the discrete-particle model is more preferred for discontinuous flow systems at smaller scales. Industry stakeholders can use these findings as guidance for choosing appropriate numerical tools to model biomass material flow in part of the optimization of material handling equipment in biorefineries.

Claudin 18.2 (CLDN18.2), a tight junction (TJ) family protein controlling molecule exchange between cells, is frequently over-expressed in gastric cancer, pancreatic adenocarcinomas and in a fraction of non–small cell lung cancer cases. The tumor properties indicate that CLDN18.2 could be an attractive drug target for gastric and pancreatic cancers. In this study, we present effective strategies for developing anti-CLDN18.2 therapeutic candidates, based on variable domain of heavy chain of heavy chain antibodies (VHHs). CLDN18.2-specific VHHs were isolated by panning a phage display library from an alpaca immunized with a stable cell line highly expressing CLDN18.2. Humanized VHHs fused with human IgG1 Fc, as potential therapeutic candidates, exhibited desirable binding specificity and affinity to CLDN18.2. In vitro experiments showed that hu7v3-Fc was capable of eliciting both antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) on CLDN18.2 positive tumor cells. In the mouse xenograft model, the anti-tumor efficacy of hu7v3-Fc was significantly more potent than Zolbetuximab, the benchmark anti-CLDN18.2 monoclonal antibody. Moreover, in vivo biodistribution using zirconium-89 (89Zr) labeled antibodies demonstrated that hu7v3-Fc (89Zr-hu7v3-Fc) exhibited a better tumor penetration and a faster tumor uptake than Zolbetuximab (89Zr-Zolbetuximab), which might be attributed to its smaller size and higher affinity. Taken together, anti-CDLN18.2 hu7v3-Fc is a promising therapeutic agent for human CLDN18.2 positive cancers. Furthermore, hu7v3 has emerged as a potential module for novel CLDN18.2 related therapeutics.

In this work, an including the switched evolution process discrete model of a DC–DC converter feeding a switched constant power load is proposed based on the Poincaré mapping rule and matrix exponent method. Numerical simulations of the bifurcation scheme based on the proposed discrete model reveal the period-adding bifurcation structures of the system as multiple devils’ staircases. Further, the calculation of the stable regions of the multiple-period orbits of the nested period-adding bifurcation structures are illustrated. The experimental results verify the validity of the discrete model and analytical accuracy of the period-adding bifurcation characteristics of the system. The proposed model solves the difficulties associated with discrete modeling for power electronic nonlinear switched systems. The introduction of the switched evolution process in the proposed discrete model provides a specific mathematical model for studying the influence of the switched evolution process on the dynamics of power electronic nonlinear switched systems. This study is expected to be a foundation for the theory and further research on such power electronic nonlinear switched systems.

Abstract Purpose Increasing evidence has shown that the transcription factor SOX4 is closely associated with the development and progression of many malignant tumors. However, the effect of SOX4 on breast cancer is unclear. In this study, we purposed to investigate the role of SOX4 in the growth and metastasis in breast cancer and the underlying mechanism. Moreover, the effect of SOX4 on cancer cell resistance to chemotherapeutic agents was also evaluated in vitro and in vivo. Methods We used lentivirus technique to ectopically express SOX4 in MDA-MB-231 and SUM149 cells or knockdown SOX4 in BT474 cells, and examined the effect of these changes on various cellular functions. MTT assay was used to determine the cell viability as well as resistance to chemotherapeutic agents. The regulation of SOX4 on epithelial-mesenchymal transition (EMT)-related genes was analyzed using qRT-PCR. The binding of SOX4 to the CXCR7 gene was demonstrated using chromatin immunoprecipitation assay and dual-luciferase reporter activity assay. The effect of SOX4/CXCR7 axis on metastasis was examined using Transwell migration and Matrigel invasion assays. The expression of SOX4/CXCR7 in primary tumors and metastatic foci in lymph nodes was assessed using immunohistochemistry. Cellular morphology was investigated under phase contrast microscope and transmission electron microscopy. Moreover, the effect of SOX4 on tumor growth, metastasis, and resistance to chemotherapy was also studied in vivo by using bioluminescent imaging. Results SOX4 increased breast cancer cell viability, migration, and invasion in vitro and enhanced tumor growth and metastasis in vivo. It regulated EMT-related genes and bound to CXCR7 promoter to upregulate CXCR7 transcription. Both SOX4 and CXCR7 were highly expressed in human primary tumors and metastatic foci in lymph nodes. Treatment of breast cancer cells with the CXCR7 inhibitor CCX771 reversed the SOX4 effect on cell migration and invasion. Ectopic expression of SOX4 increased the susceptibility of cells to paclitaxel. Conclusions SOX4 plays an important role in the growth and metastasis of breast cancer. SOX4/CXCR7 may serve as potential therapeutic targets for the treatment. Paclitaxel may be a good therapeutic option if the expression level of SOX4 is high.

Our previous study indicated that intravenous vitamin C (IVC) treatment concurrent with modulated electrohyperthermia (mEHT) was safe and improved the quality of life (QoL) of non-small-cell lung cancer (NSCLC) patients. The aim of this trial was to further verify the efficacy of the above combination therapy in previously treated patients with refractory advanced (stage IIIb or IV) NSCLC. A total of 97 patients were randomized to receive IVC and mEHT plus best supportive care (BSC) (n = 49 in the active arm, receiving 1 g/kg * d IVC concurrently with mEHT, three times a week for 25 treatments in total) or BSC alone (n = 48 in the control arm). After a median follow-up of 24 months, progression-free survival (PFS) and overall survival (OS) were significantly prolonged by combination therapy compared to BSC alone (PFS: 3 months vs 1.85 months, P

Immune checkpoint inhibitors have greatly improved the prognoses of diverse advanced malignancies, including gastric and gastroesophageal junction (G/GEJ) cancer. However, the role of anti-programmed cell death protein-1 treatment in the neoadjuvant setting remains unclear. This phase 2 study aimed to evaluate sintilimab plus CapeOx as a neoadjuvant regimen in patients with advanced resectable G/GEJ adenocarcinoma. Eligible patients with resectable G/GEJ adenocarcinoma stage cT3-4NanyM0 were enrolled. Patients received neoadjuvant treatment with sintilimab (3 mg/kg for cases 1 patient) grade 3 treatment-related adverse events during neoadjuvant treatment were anemia and neutropenia (n=5 each, 13.9%). No serious adverse events (AEs) or grade 4–5 AEs were observed. Sintilimab plus oxaliplatin/capecitabine showed promising efficacy with encouraging pCR rate and good safety profile in the neoadjuvant setting. This combination regimen might present a new option for patients with locally advanced, resectable G/GEJ adenocarcinoma. Trial registration; NCT04065282.

Tumor-specific CD8+T cells are exposed to persistent antigenic stimulation which induces a dysfunctional state called “exhaustion.” Though functioning to limit damage caused by immune response, T cell exhaustion leads to attenuated effector function whereby cytotoxic CD8+T cells fail to control tumor progression in the late stage. This pathway is a dynamic process from activation to “progenitor exhaustion” through to “terminally exhaustion” with distinct properties. With the rapid development of immunotherapy via enhancing T cell function, new studies are dissecting the mechanisms and identifying specific biomarkers of dynamic differentiation during the process of exhaustion. Further, although immune checkpoint inhibitors (ICIs) have achieved great success in clinical practice, most patients still show limited efficacy to ICIs. The expansion and differentiation of progenitor exhausted T cells explained the success of ICIs while the depletion of the progenitor T cell pool and the transient effector function of terminally exhausted T cells accounted for the failure of immune monotherapy in the context of exorbitant tumor burden. Thus, combination strategies are urgent to be utilized based on the reduction of tumor burden or the expansion of the progenitor T cell pool. In this review, we aim to introduce the concept of homeostasis of the activated and exhausted status of CD8+T cells in the tumor immune microenvironment, and present recent findings on dynamic differentiation process during T cell exhaustion and the implications for combination strategies in immune therapy.

In this paper, we provide a comprehensive performance analysis of simultaneous wireless information and power transfer (SWIPT) for cognitive relay networks with different relay schemes. In the considered system, the energy-constrained secondary transmitter harvests the energy from the primary signal and then employs the harvested energy to forward the primary signal along with the secondary signal simultaneously. To improve the spectral efficiency, we propose a novel cooperative spectrum sharing protocol with dynamic time-slot allocation based on energy harvesting, namely, dynamic time-power-based cooperative spectrum sharing protocol. Considering the delay-limited transmission mode, we analytically derive the exact closed-form expressions of outage probabilities and achievable throughput for both the primary and secondary networks with amplify-and-forward and decode-and-forward relaying schemes, respectively. More importantly, different from the existing works, we take into account the power outage probability at the energy-constrained secondary transmitter to better match the reality. Finally, the numerical results are provided to evaluate the effect of different key parameters on the system performance, which demonstrate that the dynamic cooperative spectrum sharing protocol improves the outage performance compared with the uniform time-slot allocation scheme.

The negative impedance characteristics of a constant power load (CPL) can easily lead to the instability of the DC bus voltage. To improve the stability of the DC bus voltage, an adaptive backstepping sliding mode control strategy for a boost converter with the CPL in DC microgrid is proposed. First, to carry out the backstepping control, the zero dynamic stability of the system under different output functions is studied by using input-output exact feedback linearization theory. The model is transformed into a linear system in Brunovsky canonical form, which solves the nonlinear problem caused by the CPL and the non-minimum phase problem of the boost converter. Then, under the premise of ensuring large signal stability, an adaptive mechanism is introduced into the design of the backstepping sliding mode control. The adaptive backstepping sliding mode controller is designed by adaptively updating the switching gain in real time. Furthermore, the Lyapunov theory is used to prove the global asymptotic stability of the overall closed-loop system. Finally, the numerical simulation and experimental results show that the proposed control strategy has better dynamic regulation performance and stronger robustness compared with the conventional double closed-loop PI control method.

Abstract Background We aimed to compare mediastinoscopy-assisted esophagectomy (MAE) with the Ivor Lewis procedure in T2 middle and lower thoracic esophageal carcinoma patients in fields of perioperative complications and overall survival (OS). Methods The clinical data of 112 T2 esophageal cancer patients who received MAE (n = 31) or Ivor Lewis procedure (n = 81) from January 2010 to December 2015 were retrospectively analyzed in propensity score analysis. Thirty-eight T2 esophageal cancer patients who underwent MAE (n = 19) and Ivor Lewis procedure (n = 19) were included in this study. The perioperative conditions and OS were analyzed. Results The MAE group showed shorter operation time (143.2 ± 20.6 vs 176.8 ± 31.1 min, P = 0.001), less drainage in 24 h (119.2 ± 235.1 vs 626.3 ± 396.3 mL, P

It is important for aquaculture monitoring, scientific planning, and management to extract offshore aquaculture areas from medium-resolution remote sensing images. However, in medium-resolution images, the spectral characteristics of offshore aquaculture areas are complex, and the offshore land and seawater seriously interfere with the extraction of offshore aquaculture areas. On the other hand, in medium-resolution images, due to the relatively low image resolution, the boundaries between breeding areas are relatively fuzzy and are more likely to ‘adhere’ to each other. An improved U-Net model, including, in particular, an atrous spatial pyramid pooling (ASPP) structure and an up-sampling structure, is proposed for offshore aquaculture area extraction in this paper. The improved ASPP structure and up-sampling structure can better mine semantic information and location information, overcome the interference of other information in the image, and reduce ‘adhesion’. Based on the northeast coast of Fujian Province Sentinel-2 Multispectral Scan Imaging (MSI) image data, the offshore aquaculture area extraction was studied. Based on the improved U-Net model, the F1 score and Mean Intersection over Union (MIoU) of the classification results were 83.75% and 73.75%, respectively. The results show that, compared with several common classification methods, the improved U-Net model has a better performance. This also shows that the improved U-Net model can significantly overcome the interference of irrelevant information, identify aquaculture areas, and significantly reduce edge adhesion of aquaculture areas.

Aims. Predicting the prognosis of gastric cancer using tumour-node-metastasis (TNM) staging is difficult as patients with the same TNM stage exhibit different prognoses. Methods. This study investigated the prognostic value of the preoperative fibrinogen/albumin ratio (FAR)-systemic inflammation response index (SIRI) score in resectable gastric cancer (rGC). Results. Clinicopathological features of 231 rGC patients were analysed retrospectively. Patients were divided into three groups: FAR-SIRI score 2 (FAR≥0.071 and SIRI≥0.84), 1 (FAR

Aims: It remains controversial to choose the optimal equation to estimate glomerular filtration rate (GFR) in chronic kidney disease (CKD) patients with diabetes.Materials and Methods: Two hundred and fifteen diabetic CKD patients and 192 non-diabetic CKD patients were enrolled in this study. Iohexol GFR, serum creatinine (SCr), and Cystatin C(CysC) were measured simultaneously for each patient. SCr- and CysC-based estimated GFR (eGFR) were calculated through eight equations, including three CKD-EPI equations, Revised Lund-Malmö study equation (RLM), CAPA equation, and three Full Age Spectrum (FAS) equations. Bias, precision, and accuracy were compared among eGFR equations with iohexol-GFR serving as measured GFR (mGFR). Independent predictive factors of accuracy were explored using multivariate logistic regression analysis.Results: In the diabetic group, CKD-EPISCr−CysC showed the best performance among three CKD-EPI equations (interquartile range of 13.88 ml/min/1.73 m2 and 30% accuracy of 72.56%). Compared to CKD-EPISCr−CysC, the other five equations did not significantly improve the performance of GFR estimates. Mostly, eGFR equations were less accurate in diabetic group than in non-diabetic group. Significant differences were found in different mGFR range (P < 0.001). The multivariate logistic regression analysis identified that BMI, mGFR, and diabetic kidney disease (DKD) status were independent predictors of accuracy of three equations in diabetic group. HbA1c was a predictor of accuracy of CKD-EPISCr and CKD-EPICysC in diabetic group.Conclusions: This study showed that eGFR equations were less accurate in the diabetic group than in the non-diabetic group. CKD-EPIScr−CysC had the best performance among CKD-EPI equations in Chinese diabetic CKD patients. The other five equations did not significantly improve the performance of GFR estimates. BMI, mGFR, DKD status, and HbA1c were independent factors associated with accuracy in eGFR equations.

Impedance-based stability analysis is an effective method for addressing a new type of SSO accidents that have occurred in recent years, especially those caused by the control interaction between a DFIG and the power grid. However, the existing impedance modeling of DFIGs is mostly focused on a single converter, such as the GSC or RSC, and the influence between the RSC and GSC, as well as the frequency coupling effect inside the converter are usually overlooked, reducing the accuracy of DFIG stability analysis. Hence, the entire impedance is proposed in this paper for the DFIG-based WECS, taking coupling factors into account (e.g., DC bus voltage dynamics, asymmetric current regulation in the dq frame, and PLL). Numerical calculations and HIL simulations on RT-Lab were used to validate the proposed model. The results indicate that the entire impedance model with frequency coupling is more accurate, and it is capable of accurately predicting the system’s possible resonance points.

BACKGROUND Worldwide, diabetes has become the most common cause of end-stage renal disease (ESRD), yet Swiss data are largely lacking. METHODS This observational study examined ESRD patients with diabetes mellitus (ESRD-DM) at end of 2009 and 2014. The prevalence and characteristics of ESRD-DM patients were collected in all dialysis facilities in the Canton of Vaud of Switzerland in 2009 and in 2014, and the 5-year mortality rate was assessed. RESULTS A total of 107 and 140 ESRD-DM patients underwent dialysis at end of 2009 and 2014, respectively. Within the 5-year period a total of 167 incidental ESRD-DM patients required dialysis, corresponding to an estimated incidental rate of 0.84/1000 person-years in the diabetic population. In 2009, all patients with ESRD-DM underwent haemodialysis, decreasing to 96.2% in 2014, with 3.8% on peritoneal dialysis. Age, sex, body mass index, type of diabetes, duration of diabetes, cause of ESRD, dialysis duration, dialysis frequency, vascular access, and glycosylated haemoglobin levels did not differ between 2009 and 2014. In 2014, macrovascular comorbidity was reported more often than in 2009, but not amputations. Haemoglobin level decreased significantly from 117.9 g/l to 112.3 g/l. Calcium-containing phosphate binder and angiotensin-converting enzyme inhibitor use significantly decreased, whereas iron therapy significantly increased with time. The 5-year mortality rate was 61.7%. Five-year survivors were significantly younger and had a higher body mass index. CONCLUSIONS The growing prevalence of ESRD-DM emphasises that prevention of chronic kidney disease and its progression should be a public health priority in Switzerland.

Non-small-cell lung cancer is one of the most lethal cancers in the worldwide. Although Paclitaxel-based combinational therapies have long been used as a standard treatment in aggressive non-small-cell lung cancers, Paclitaxel resistance emerges as a major clinical problem. It has been demonstrated that Curcumin from Curcuma longa as a traditional Chinese medicine can inhibit cancer cell proliferation. However, the role of Curcumin in Paclitaxel-resistant non-small-cell lung cancer cells is not clear. In this study, we investigated the effect of Curcumin on the Paclitaxel-resistant non-small-cell lung cancer cells and found that Curcumin treatment markedly increased the sensitivity of Paclitaxel-resistant non-small-cell lung cancer cells to Paclitaxel. Mechanically, the study revealed that Curcumin could reduce the expression of metastasis-associated gene 1 (MTA1) gene through upregulation of microRNA-30c in Paclitaxel-resistant non-small-cell lung cancer cells. During the course, MTA1 reduction sensitized Paclitaxel-resistant non-small-cell lung cancer cells and enhanced the effect of Paclitaxel. Taken together, our studies indicate that Curcumin increases the sensitivity of Paclitaxel-resistant non-small-cell lung cancer cells to Paclitaxel through microRNA-30c-mediated MTA1 reduction. Curcumin might be a potential adjuvant for non-small-cell lung cancer patients during Paclitaxel treatment.

Existing large-signal control schemes for DC/DC converters formulate control strategies based primarily on nonlinear control theory, and the associated design and implementation are relatively complex. In this work, a decomposition modeling and inverse-system decoupling control method is proposed for DC/DC converters that operate under large-signal disturbances. First, a large-signal circuit-averaged model for DC/DC converters is established. The proposed control system has a double closed-loop control structure composed of a voltage loop and a current loop. Then, the voltage-loop and current-loop controlled subsystems are decoupled and compensated to first-order integral elements using the inverse system method. Several linear feedback controllers are designed for first-order integral systems under various optimization criteria using the optimal control theory. Simulation and experiment were performed on buck–boost converters with resistive and constant power loads. The results show that under the control of the proposed controller, all systems exhibited excellent dynamic and steady-state performance. The proposed method allows the disturbance control of the DC/DC converter, the dynamic behavior control of the voltage loop, and the current loop to become independent processes. The local controller design follows the classical linear control design method and is a simple and effective large-signal control strategy.

This paper is concerned with the existence of nontrivial periodic solutions and positive periodic solutions to a nonlinear second-order difference equation. Under some conditions concerning the first positive eigenvalue of the linear equation corresponding to the nonlinear second-order equation, we establish the existence results by using the topological degree and fixed point index theories.