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Objective: Myeloid-derived suppressor cells (MDSCs) are heterogeneous cells which can suppress T-cell functionality. Herein, we evaluated the functional importance of MDSCs in the context of kidney ischemia-reperfusion injury (IRI) and explored their ability to regulate innate and adaptive immune cell function in this context. Methods: The differentiation of MDSCs was induced in vitro by treating cells with GM-CSF and interferon (IFN)-γ. In a murine model of renal IRI, serum creatinine and blood urea nitrogen values were measured to monitor kidney function, while histopathological and immunohistochemical approaches were used to assess kidney injury severity. In addition, flow cytometry was employed to assess the phenotypes and apoptosis of kidney cells in these mice. Results: MDSCs induced by treatment with GM-CSF + IFN-γ could suppress T-cell functionality in vitro. The adoptive transfer of these MDSCs into an IRI mouse model system enhanced kidney damage and impaired renal function following the recruitment of these cells to renal tissues in these mice. Following such adoptive transfer, the relative frequency of MDSCs with a CD11b+Ly6G−Ly6Chigh monocytic-MDSC phenotype decreased, whereas cells with a CD11b+Ly6G+Ly6Clow polymorphonuclear-MDSC phenotype become more prevalent within kidney tissues following IRI. Adoptive transfer also coincided with increased frequencies of macrophages and dendritic cells (DCs) in the kidney tissues. This suggested that M-MDSCs contributed to early-stage renal IRI damage by differentiating into these deleterious cell types. However, MDSC-induced suppression of CD4+ and CD8+ T-cell infiltration was not sufficient to prevent the deterioration of renal function in these mice. Conclusions: Herein, we successfully developed a protocol wherein MDSCs were differentiated in vitro through combination GM-CSF/IFN-γ treatment. When these MDSCs were subsequently adoptively transferred into a murine model of renal IRI, they aggravated kidney damage, likely owing to the differentiation of M-MDSCs into deleterious macrophages and DCs.

The orderly release of electricity plan is an important measure for China’s electricity market reform which also lead to excessive pressure for coal power units caused by the low planned electricity quantity. Allowing high-priced units to participate in the market can effectively alleviate the market pressure. However, the participation of high-priced units in electricity market will have an impact on the declaration behavior of other generators. In this context, an evolutionary game model of bidding for two groups of generators considering the market liberalizing degree (MLD) is proposed. Above all, the profit model of two kinds of generators is proposed under two bidding strategies considering the MLD. On this basis, an evolutionary game model of generators’ bidding is built to qualitatively analyze the market equilibrium solution which is affected by the MLD coefficient. Thus, the expected evolutionary stable equilibrium of bidding can be formed spontaneously in electricity market by adjusting the MLD coefficient. The case studies are performed for demonstrating the proposed evolutionary game model of generators’ bidding, and simulation results show that different MLD and the initial state of bidding behavior of generators will influence the final evolutionary stable equilibrium of bidding market, and it also shown that the government can make the electricity market develop towards​ the expected state by adjusting MLD and supervising the bidding behavior of generators.

Background The 5-α reductase inhibitors (5-ARIs) are the first-line drug managing benign prostatic hyperplasia (BPH). Unfortunately, some patients showed no responses to 5-ARIs therapy, even suffering from worse symptoms. Although the decreased expression of 5-α reductase type 2(SRD5A2) in BPH tissues might explain the 5-ARIs therapy failure, the mechanisms underlying SRD5A2 decreased remained unelucidated. Objectives To investigate the mechanisms of microRNA regulating the variable expression of SRD5A2 resulting in treatment failure of 5-ARIs. Materials and methods The expression of SRD5A2 and microRNAs in BPH tissues and prostate cells were detected by immunohistochemistry, western blotting, and quantitative real-time PCR (qRT-PCR). Dual-luciferase reporter assay was performed to confirm that microRNA directly combine to SRD5A2 mRNA. The apoptosis of prostatic cells was detected by flow cytometry. Results 13.6%, 28.8%, and 57.6% of BPH tissues showed negative, weak, and strong positive SRD5A2 expression, respectively. Normal human prostatic epithelial cell line RWPE-1 strongly expressed SRD5A2, whereas the immortalized human prostatic epithelial cell line BPH-1 weakly expressed SRD5A2. miR-1199-5p expression level in BPH-1 was remarkably higher than that in RWPE-1(P༜0.001), and miR-1199-5p expression was significantly upregulated in BPH tissues with negative SRD5A2 expression than those with positive SRD5A2 expression. After miR-1199-5p mimics transfection, SRD5A2 expression was decreased markedly in RWPE-1 cells, whereas after miR-1199-5p inhibitor transfection, SRD5A2 expression increased in BPH-1 cells. Dual-luciferase reporter assay showed that miR-1199-5p could bind the 3’ untranslated region of SRD5A2. Additionally, miR-1199-5p could decrease the sensibility of finasteride (100 µM) on RWPE-1 cells. Conclusion Our results demonstrate that SRD5A2 expression varied in BPH tissues and miR-1199-5p might be one of the several factors contributing to differential SRD5A2 expression in BPH patients.

An energy deviation settlement (EDS) mechanism has been proposed to settle the deviation between consumption and energy contracts in China's forward electricity market. Due to high EDS costs of electricity retailers, a deviation mutual insurance (DMI) mechanism is put forward, representing an option for electricity retailers to reduce the deviation through contract transfer. Given this background, an optimal alliance strategy is proposed to maximize the utility of different types of individual electricity retailers. The alliance income model considers the EDS cost reduction and the cooperation cost analyzed based on transaction cost theory (TCT). An improved income allocation method, which considers distribution indexes selected by game theory and resource dependence theory (RDT), is proposed to ensure the comprehensive and reasonable allocation of alliance income. Considering the expected income and financial risk, an evaluation model using conditional value at risk (CVaR) as the financial risk assessment indicator is presented to measure the stability of alliances. Simulations based on data from a provincial electricity market in China illustrate that the EDS costs of retailers can be reduced by selecting appropriate partners for alliance. In addition, the proposed alliance income allocation method is more reasonable and more targeted than the cooperative game-based methods.

China's electricity market reform is constantly advancing, and market rules change frequently. On the basis of sorting out the technical advantages of micro service and HMI configuration of electricity trading, and using the decoupling characteristics of front-end and back-end of micro service, a rapid response technology architecture of electricity trading platform with "front-end HMI configuration + back-end microservice" is proposed, and the corresponding key technologies are studied. The results of this paper have been applied in the construction of a new generation of ETP and achieved good results.

With the integration of the ultra-high-voltage direct-current (UHVDC) of large capacity, the scheduled outputs of the power plants are limited, and the direct power purchase (DPP) by large consumers is influenced. The negative impact caused by the failure modes of the UHVDC on the economic dispatch (ED) and the security of the power system is to be studied. Here, the derated capacities of the UHVDC are described together with their state probabilities. To maximise the profit of power plants, an ED model with the DPP is proposed. The relationship between the amount of the DPP and the power transmission by the UHVDC is decided based on two contract strategies for the DPP. The interior-point method is applied to solve the ED problem. The simulation results validate the feasibility and accuracy of the proposed model, which is beneficial to the development of the power market and the UHVDC in China.

At present, electricity transaction in China is mainly conducted by medium- and long-term market contracts, while the spot electricity market has not yet been implemented. An appropriate energy imbalance processing mechanism for medium- and long-term power transactions is highly demanded for maintaining the stability of market operation, since it is supposed to guide market participants to reduce system imbalances and actively provide balancing services. Given this background, a bi-level optimization model for developing optimal bidding strategies of power producer in the monthly sequential contract and balancing markets is proposed based on the currently implemented monthly pre-listing balancing mechanism in China. In the upper level of the model, the monthly utility which makes a tradeoff between revenues and risks produced by the bidding strategy of the producer in the monthly sequential energy dual-market is maximized, considering the uncertainties of the monthly energy imbalances in the power system and the bidding strategies of rivals. In the lower level, the dispatch cost is minimized by simulating the three-stage process of sequential system operation, which includes contract market clearing by power exchange (PX), energy decomposition and modification by the system operator (SO) and balancing market clearing by PX. The simulation results of an eastern provincial electricity market in China show that the presented model can assist power producers in adjusting their monthly bidding strategies with relevant factors, such as the minimum output level of each producer, risk preference, and forecast information including system energy imbalance status and bidding strategies of rivals. In addition, the proposed method is also helpful for market designers in setting market parameters, such as government-authorized contract energy proportion and settlement thresholds in the balancing market.

With fast development of the retail market of China in recent years, the risk of the market needs to be quantified. This paper provides a detailed framework to assess and classify the risk of the market. The neural network is used to predict the risk. Time-dependent weight is used to describe cumulative effect. With the S-shaped curve, the risk factors are classified by safety, competition and elimination. The entropy method is used to set weights of the risk factors. The K-means clustering is used to classify the companies or periods. The risk factors, the operational risk, and the risk indicators form a hierarchical framework. The state aggregation based on serial tracking and incidence matrix finds transition rate matrix for early warning and coordination. The numerical results of a market with 9 companies are provided to validate the effectiveness of the proposed model.

Jiaji Duck (JJ) is a Muscovy duck species that possesses many superior characteristics, and it has become an important genetic resource in China. However, to date, its genetic characteristics and genetic relationship with other duck breeds have not been explored yet, which greatly limits the utilization of JJ. In the present study, we investigated the genome sequences of 15 individual ducks representing five different duck populations, including JJ, French Muscovy duck (FF), mallard (YD), hong duck (HD) and Beijing duck (BD). Moreover, we investigated the characteristics of JJ-specific single nucleotide polymorphisms (SNPs) and compared the genome sequences of JJ vs. YD and JJ vs. BD using integrated strategies, including mutation detection, selective screening, and Gene Ontology (GO) analysis. More than 40 Gb of clean data were obtained for each population (mean coverage of 13.46 Gb per individual). A total number of 22,481,367 SNPs and 4,156,829 small insertion-deletions (Indels) were identified for the five duck populations, which could be used as molecular markers in breeding and utilization of JJ. Moreover, we identified 1,447,932 JJ-specific SNPs, and found that genes covering at least one JJ-specific SNP mainly involved in protein phosphorylation and dephosphorylation, as well as DNA modification. Phylogenetic tree and principal components analysis (PCA) revealed that the genetic relationship of JJ was closest to FF, while it was farthest to BD. A total of 120 and 111 genes were identified as positive selection genes for JJ vs. BD and JJ vs. YD, respectively. GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the positive selection genes for JJ vs. BD ducks mainly involved in pigmentation, muscle contraction and stretch, gland secretion, and immunology, while the positive selection genes obtained from JJ vs. YD ducks mainly involved in embryo development, muscle contraction and stretch, and gland secretion. Taken together, our findings enabled us to better understand the characteristics of JJ and provided a molecular basis for the breeding and hybrid utilization of JJ in the future.

The retail electricity market is becoming prosperous in China in the recent years. However, due to many uncertain factors, the retail providers may go bankrupt and have to withdraw from the retail market, thus the customers will suffer from unexpected supply interruption and economic loss, which will disturb the healthy operation of the electricity market. The purpose of the last resort service is to take the responsibility of the bankrupted providers, and maintain the power supply to the customers. This service is often provided by retail electric providers in foreign countries while undertaken by the power grid companies in China. In this paper, the experiences of the last resort service in several foreign countries are investigated. The qualification, pricing, customer allocation, and operating process about the last resort service are investigated. The benefit and risk of the last resort service are analyzed to determine the sharing of the responsibilities, interests, and punishments among the participants of the retail market. Based on the investigation, some practical suggestions to the last resort service are given to the provincial retail market in China.

In order to support the development of renewable energy, countries around the world have adopted certain renewable energy incentive mechanisms, including feed-in tariff (FIT) and renewable portfolio standard (RPS). Based on the official report concerning renewable energy consumption issued by the Chinese government in 2018, FIT is no longer an ideal renewable incentive mechanism for China. The increasing financial burden of renewable subsidies on the government has prompted a transition from FIT to a more market-based RPS mechanism. However, the abrupt transformation from FIT to RPS without any transitions might potentially cause problems, including a lack of incentives for market participants and a high market risk. Feed-in premium (FIP), which is a transformation based on FIT, can increase the flexibility of the mechanism and play an important role in the transitional period. However, to date, there has only been limited research work that has explored the effect of implementing FIP-RPS in the development of renewable energy in China. It is still not clear how this transition could be carried out smoothly. Therefore, this research was aimed to devise a joint FIP-RPS mechanism and further develop the optimal combination ratio of the two, so as to obtain a socially optimal mechanism design. The simulation results showed that, at different stages of renewable energy development, FIP and RPS should be implemented according to their distinct characteristics, and the joint FIP-RPS mechanism should be combined with different ratios. It could be indicated that the proposed joint FIP-RPS mechanism not only excels at promoting renewable energy, but is also capable of maintaining desirable market prices and social welfare in this transitional period, as compared to FIP and RPS implemented alone. In the future, a certain degree of FIP-RPS implementations to this type of energy transition would be one of the preferred methods that could be implemented to have a considerable influence on China&rsquo, s national energy plan. This is because the combination of the two mechanisms not only reduces the financial burden of the government, but also plays an active role in the renewable energy market.

The increasing capacity of the grid-connected solar system has negative influence on the power grid. This paper focuses on the quality evaluation of the solar power. The quality of the solar power is quantified by the penalty function, which considers the total output, the output fluctuation and the forecast error. Firstly, the K-means clustering technique to cluster the sample data of the indices is applied. Then, the significance test using the F-distribution is applied to validate the effectiveness of the proposed model. Finally, the penalty function is proposed. The logarithmic function, the power function, and the exponential function are applied to compare the influences of each index on the penalty function. The Analytic Hierarchy Process (AHP) and the entropy method are used to determine the weight coefficients. The feasibility and application value of the proposed model are validated by the numerical results.

An electric vehicle aggregator (EVA) can participate strategically in an electricity market, on behalf of a large number of electric vehicle (EV) owners. Strategic bidding optimization and charging management for each EVA can benefit both the power system and EVA. In this work, a hierarchical optimization model for developing optimal bidding strategy and charging management in a real-time (RT) electricity market is proposed for each EVA to minimize its costs. The developed model is formulated as a two-level optimization problem in the framework of the well-established model predictive control (MPC). The first level optimization is to determine the optimal hourly RT bidding strategy of the EVA by a two-stage stochastic predictive optimization, with the charging scheduling of EVs formulated as a linear recourse problem. The second level optimization is to manage the RT charging of EVs in each time interval according to the cleared bidding quantity in the RT market, which can be formulated as a predictive linear programming problem. Both the first level and second level problems are optimized using the commercial solver Gurobi interfaced with Python language. Case studies demonstrate that the EVA can strategically participate in the RT electricity market and attain more benefits by utilizing the proposed strategy.

Introduction Post-infectious immunosuppression is disadvantageous to patients' long-term outcomes, especially in transplant recipients receiving large doses of immunosuppressants. A growing body of evidence indicates the immunoregulatory ability of myeloid-derived suppressor cells (MDSCs). We herein investigate the characteristics of monocytic-MDSCs (M-MDSCs) in a cohort of renal transplant recipients with/without infection to clarify the potential involvement in post-infectious immunosuppression. Methods The study prospectively included 28 adult recipients who underwent allogeneic ABO-compatible renal transplant. Blood samples were drawn at day 0, 7, 14, 28, 60 and 90 postoperation. The incidence of infection and treatment strategies were recorded. The frequency and absolute number of peripheral blood M-MDSCs as well as other immune cells were determined by flow cytometry. Immnosuppressive functions of M-MDSCs were analyzed by inhibition of T cells proliferation. mRNA levels of immunosuppressive molecules in sorted M-MDSCs were also examined. Results 7 recipients were diagnosed with bacterial (n = 5) or viral (n = 2) infection and 3/5 of bacterial-infected recipients suffered from secondary infection during further follow-up. In the non-infected group, M-MDSCs numbers increased transiently during the early postoperative period, however, bacterial but not viral infection led to significant and persistent accumulation of M-MDSCs that remained at high levels after anti-infective treatments. M-MDSCs from infected recipients demonstrated potent ability to suppress T cells proliferation in vitro and negatively correlated with lymphocytes in vivo, yet not in the non-infected group. Inducible nitric oxide synthase (iNOS) mRNA levels were higher in sorted M-MDSCs when compared with monocytes, and suppressive activity was reversed by addition of a NOS inhibitor. Conclusions Circulating M-MDSCs underwent significant and persistent increases after bacterial infection in renal transplant recipients, contributing to post-infectious immunodeficiency. Therefore, special attention should be given to M-MDSCs during the monitoring of immune status and infection management.

Intramuscular fat (IMF) is recognized as the predominant factor affecting meat quality due to its positive correlation with tenderness, juiciness, and flavor. Chicken IMF deposition depends on the balance among lipid synthesis, transport, uptake, and subsequent metabolism, involving a lot of genes and pathways, however, its precise molecular mechanisms remain poorly understood. In the present study, the breast muscle tissue of female Wenchang chickens (WC) (higher IMF content, 1.24 in D120 and 1.62 in D180) and female White Recessive Rock chickens (WRR; lower IMF content, 0.53 in D120 and 0.90 in D180) were subjected to RNA-sequencing (RNA-seq) analysis. Results showed that many genes related to lipid catabolism, such as SLC27A1, LPL, ABCA1, and CPT1A were down-regulated in WC chickens, and these genes were involved in the PPAR signaling pathway and formed an IPA® network related to lipid metabolism. Furthermore, SLC27A1 was more down-regulated in WRR.D180.B than in WRR.D120.B. Decreased cellular triglyceride (TG) and up-regulated CPT1A were observed in the SLC27A1 overexpression QM-7 cells, and increased cellular triglyceride (TG) and down-regulated CPT1A were observed in the SLC27A1 knockdown QM-7 cells. These results suggest that lower lipid catabolism exists in WC chickens but not in WRR chickens, and lower expression of SLC27A1 facilitate IMF deposition in chicken via down-regulated fatty acid oxidation mediated by CPT1A. These findings indicate that reduced lipid catabolism, rather than increased lipid anabolism, contributes to chicken IMF deposition.

Intramuscular fat (IMF) is recognized as the predominant factor affecting meat quality due to its positive correlation with tenderness, juiciness, and flavor. Chicken IMF deposition depends on the balance among lipid synthesis, transport, uptake, and subsequent metabolism, involving a lot of genes and pathways, however, its precise molecular mechanisms remain poorly understood. In the present study, the breast muscle tissue of female Wenchang chickens (WC) (higher IMF content, 1.24 in D120 and 1.62 in D180) and female White Recessive Rock chickens (WRR; lower IMF content, 0.53 in D120 and 0.90 in D180) were subjected to RNA-sequencing (RNA-seq) analysis. Results showed that many genes related to lipid catabolism, such as SLC27A1, LPL, ABCA1, and CPT1A were down-regulated in WC chickens, and these genes were involved in the PPAR signaling pathway and formed an IPA® network related to lipid metabolism. Furthermore, SLC27A1 was more down-regulated in WRR.D180.B than in WRR.D120.B. Decreased cellular triglyceride (TG) and up-regulated CPT1A were observed in the SLC27A1 overexpression QM-7 cells, and increased cellular triglyceride (TG) and down-regulated CPT1A were observed in the SLC27A1 knockdown QM-7 cells. These results suggest that lower lipid catabolism exists in WC chickens but not in WRR chickens, and lower expression of SLC27A1 facilitate IMF deposition in chicken via down-regulated fatty acid oxidation mediated by CPT1A. These findings indicate that reduced lipid catabolism, rather than increased lipid anabolism, contributes to chicken IMF deposition.

Understanding the dynamics of the key pectinase, polygalacturonase, and improving its thermotolerance and catalytic efficiency are of importance for the cost-competitive bioconversion of pectic materials. By combining structure analysis and molecular dynamics (MD) simulations, eight mutagenesis sites having the potential to form cation-π interactions were identified in the widely used fungal endo-polygalacturonase PG63. In comparison to the wild-type, three single mutants H58Y, T71Y and T304Y showed improved thermostability (the apparent Tms increased by 0.6−3.9 °C) and catalytic efficiency (by up to 32-fold). Chromatogram analysis of the hydrolysis products indicated that a larger amount of shorter sugars were released from the polygalacturonic acid by these three mutants than by the wild-type. MD analysis of the enzyme-substrate complexes illustrated that the mutants with introduced cation-π interaction have modified conformations of catalytic crevice, which provide an enviable environment for the catalytic process. Moreover, the lower plasticity of T3 loop 2 at the edge of the subsite tunnel appears to recruit the reducing ends of oligogalacturonide into the active site tunnel and initiates new hydrolysis reactions. This study demonstrates the importance of cation-π interaction in protein conformation and provides a realistic strategy to enhance the thermotolerance and catalytic performance of endo-polygalacturonases.

The reliability of power electronic converters is a major concern in industrial applications because of the use of high-power semiconductor devices, which have high-power density and higher failure rates. Potential defects inside an insulated gate bipolar transistor (IGBT) module can be seen as precursors of being about to wear out, and are important for health monitoring of the IGBT module which is used to enhance reliability. Aiming to do reliability assessment about three-level inverters, this paper proposes an appropriate method based on fault-tolerant control circuit, uniquely fine-tuned for inverter (or general converter) evaluation. The proposed prognostic approach uses terminal voltages of IGBT as a precursors to monitor the bond wire health, which can give accurate predictions and allow operators to observe unhealthy IGBT modules inside a power converter, and then take appropriate measures timely to avoid breakdown.

Additional file 1. Multiple sequence alignment of deduced TlGlu16A and five other fungal counterparts of GH16.

This paper presents a novel 4-level converter with switch capacitor and boost circuit, meanwhile, introduces its control strategy for a three-phase switched reluctance (SR) drive. The proposed 4-level converter adds one switch, two diodes, one capacitor and one inductance to the front end of a conventional asymmetric converter. The added capacitor and original dc-link capacitor could be connected both in series and in parallel. The performance of SRM is closely related to the supply voltage. High voltage can reduce the time that current flows within the commutation period, and improve the output torque. However, high voltage is not always favorable. For example, higher voltage in the range of low rotational speeds will improve transistors switching frequency, and that causes rise of switching losses. Therefore, the converter having variable output voltage is very useful. The terminal voltage of the converter side is at general dc-link capacitor voltage. Meanwhile, the voltage also could be up to a double dc-link capacitor voltage level to adapt different operation conditions. In this paper, a detailed analysis of current-overlap modes is also presented. The compared simulation and experiments are done. The results verify the performance of the proposed converter.

A direct instantaneous torque control (DITC) of switched reluctance motor (SRM) with a three-bridge five-level converter is presented in this paper. Compared with conventional asymmetric half bridge converter, the proposed converter has more switching states, which can contribute significantly to reducing torque ripples and smoothing the total output torque. Additionally, in consideration of the unbalance of dc-link capacitor voltages, appropriate switching states are selected to achieve dynamic balance of the dc-link capacitor voltages. The validity of proposed DITC method applied with the five-level converter is verified by comparing its simulation and experimental results with the ones of traditional DITC method under a three-phase asymmetric half bridge converter.

With the development of modern electricity equipment, voltage dips may bring more and more economic losses, which need a proper method of evaluation. In this paper, a time varying quality loss function, utilizing the Tobit model, is used to predict economic losses due to voltage dips. This quality loss function is more flexible and closer to practical situation.