This paper proposes an energy management technique for a consumer-to-grid system in smart grid. The benefit to consumers is made the primary concern to encourage consumers to participate voluntarily ...in energy trading with the central power station (CPS) in situations of energy deficiency. A novel system model motivating energy trading under the goal of social optimality is proposed. A single-leader multiple-follower Stackelberg game is then studied to model the interactions between the CPS and a number of energy consumers (ECs), and to find optimal distributed solutions for the optimization problem based on the system model. The CPS is considered as a leader seeking to minimize its total cost of buying energy from the ECs, and the ECs are the followers who decide on how much energy they will sell to the CPS for maximizing their utilities. It is shown that the game, which can be implemented distributedly, possesses a socially optimal solution, in which the sum of the benefits to all consumers is maximized, as the total cost to the CPS is minimized. Numerical analysis confirms the effectiveness of the game.
A resonant optical tunneling effect (ROTE) is a special phenomenon that bridges the wave optics and the quantum physics, and has attracted continuous research efforts for many years. This paper aims ...to summarize the latest progress of the ROTE in theoretical modeling and application studies. As the background, the analogies of photon tunneling and electron tunneling are first discussed using different optical structures and their corresponding quantum configurations. Then, two theoretical models are presented based on the optics interpretation and the quantum interpretation, respectively. Next, the applications of the ROTE are explored for optical switches and refractive index sensors. Finally, brief discussions are presented to distinguish the ROTE from some other similar phenomena.
Generalized spatial modulation (GSM) is a spectral and energy efficient multiple-input-multiple-output transmission technique. The low-complexity detection algorithm design with near maximum ...likelihood (ML) performance at the receiver is very challenging, and is the focus of this letter. In specific, we exploit the fixed sparsity constraint in the transmitted GSM signals, and take advantage of Bayesian compressive sensing (BCS) in sparse signal recovery. A new detection algorithm, referred to as enhanced Bayesian compressive sensing (EBCS), is proposed. It features more than 75% complexity reduction at high signal-to-noise ratios compared with the ordered-blocked minimum-mean-squared-error algorithm. Furthermore, it is shown by simulation that its error performance is comparable to the ML algorithm, and the performance gap is negligible in many cases.
Frequency-dependent I/Q imbalance estimation and compensation are of significant practical importance to low-cost wideband systems with an I/Q modulation architecture. To enable multichannel ...transmission without inter-channel interference, transmitter I/Q imbalance must be pre-compensated to meet stringent transmit mask requirement. In this paper, a simple frequency domain joint transmitter and receiver I/Q imbalance estimation method is proposed for self-calibration of such wideband multichannel transceivers. Using two frequency domain training signals and a phase shifter inserted in the transceiver local loopback channel, the transmitter and receiver I/Q imbalances can be estimated separately. The estimation errors are also analyzed and the mean square error lower bounds are derived. Simulation results are in good agreement with analytical ones. Compared with existing methods, the proposed technique demonstrates better image rejection performance and quicker adaptation to parameter changes, making it more applicable to many wireless systems, especially the multichannel microwave backhaul, for achieving high data rates with high-order modulation and wide transmission bandwidth.
The lack of effective early diagnostic markers is an obstacle in clinical diagnosis and treatment of hepatocellular carcinoma (HCC). Matrix-assisted laser desorption/ionization time-of-flight mass ...spectrometry (MALDI-TOF MS) is an increasing popular approach for identification of clinically relevant parameters including biomarkers.
540 subjects, including 274 HCC, 119 liver cirrhosis, 89 hepatitis, and 58 healthy volunteers were enrolled. MALDI-TOF MS was used to select potential novel biomarkers from serum of HCC patients. Its clinical application was evaluated by experiments and clinical data analysis.
We identified Thymosin β4 (Tβ4) in serum by MALDI-TOF MS. The expression of Tβ4 was detected up-regulating in HCC cells and tissues which enhanced motility of HCC cells. More important, the level of serum Tβ4 was significantly elevated in HCC patients. The AUROC showed the optimum diagnostic cut-off was 1063.6 ng/mL, ROC and 95% CI of Tβ4 (0.908; 0.880-0.935) were larger than that of serum AFP (0.712; 0.662-0.762; p < 0.001). The sensitivity (91.3% vs 83.1%) and specificity (81.2% vs 20.3%) of serum Tβ4 were higher than alpha-fetoprotein (AFP). In AFP-negative HCC, the sensitivity could reach to 80.5%. ROC analysis showed serum Tβ4 had a better performance compared with AFP in distinguishing early-stage and small HCC. Tβ4 is correlated with TNM stage (p = 0.016) and vascular invasion (p = 0.005). Survival analysis indicated the survival time of Tβ4 positive patients was shorter (p < 0.001). Cox analysis suggested Tβ4 could be an independent factor for HCC prognosis.
Tβ4 may serve as a novel biomarker for HCC diagnosis and prognosis.
AIM: To investigate the effect of Girdin knockdown on the chemosensitivity of colorectal cancer cells to oxaliplatin and the possible mechanisms involved.METHODS: Four siRNAs targeting Girdin were ...transfected into the chemoresistant colorectal cancer cell line DLD1. Real-time polymerase chain reaction(PCR) was employed to assess Girdin mRNA expression and the most effective siRNA was chosen for conversion into shRNA. Then, DLD1 cells were infected with lentiviruses expressing the Girdin shRNA and a scramble control, respectively, and Girdin mRNA and protein expression levels were assessed by real-time PCR and Western blotting. Furthermore, microarray experiments were used to assess global gene expression profile after Girdin suppression in DLD1 cells. Finally, the cytotoxic effect of simultaneous treatment with oxaliplatin and adriamycin(an inhibitor of a significantly downregulated gene after Girdin suppression in DLD1 cells) was examined by MTT assay.RESULTS: The most effective siRNA suppressed Girdinexpression with an inhibition efficiency of 57%. Compared with the scramble control, DLD1 cells infected with the Girdin shRNA displayed decreased Girdin mRNA and protein levels(P < 0.05), and Girdin knockdown significantly enhanced chemosensitivity to oxaliplatin in colorectal cancer cells(P < 0.05). Microarray data revealed that 381 and 162 genes were upregulated and downregulated in response to Girdin reduction, respectively, with ratios > 1.2 or < 0.8(P < 0.01). Interestingly, TOP2B(DNA topoisomerase 2-β) was downregulated(ratio = 0.78, P = 0.0001) and oxaliplatin/adriamycin combination resulted in increased cell death compared with treatments with individual agents(P < 0.05).CONCLUSION: Girdin knockdown enhances chemosensitivity of colorectal cancer cells to oxaliplatin via TOP2B down-regulation. These findings provide a promising approach to overcome the chemoresistance of colorectal cancer cells.
In this paper, we propose a new linear vector physical-layer network coding (NC) scheme for spatial multiplexing multiple-input multiple-output (MIMO) two-way relay channel (TWRC) where the channel ...state information (CSI) is not available at the transmitters. In this scheme, each user transmits M independent quadrature amplitude modulation signal streams respectively from its M antennas to the relay. Based on the receiver-side CSI, the relay determines a NC generator matrix for linear vector network coding, and reconstructs the associated M linear combinations of all messages. We present an explicit solution for the generator matrix that minimizes the error probability at a high SNR, as well as an efficient algorithm to find the optimized solution. We propose a novel typical error event analysis that exploits a new characterization of the deep fade events for the TWRC. We derive a new closed-form expression for the average error probability of the proposed scheme over a Rayleigh fading MIMO TWRC. Our analysis shows that the proposed scheme achieves the optimal error rate performance at a high SNR. Numerical results show that the proposed scheme significantly outperforms existing schemes, and match well with our analytical results.
A distributed multiple-input-multiple-output (MIMO) system consists of M users served by L distributed base stations (BSs), where the BSs are connected to a central unit (CU) via L independent ...backhaul (BH) links. In this paper, we consider the design of an uplink distributed MIMO system where 1) the channel state information is not available at the transmitters and 2) the BH links are rate constrained. We propose a new linear network coding (LNC)-based protocol: the M users transmit simultaneously. Each BS generates N linear functions of the M users' messages, based on a preassigned LNC coefficient matrix. The CU collects N · L linear functions from the L BSs and recovers all M users' messages by solving these linear functions. The decoding becomes successful if the linear functions has full rank M and fails if the linear functions are rank deficient. We derive the preassigned LNC coefficient matrix that minimizes the probability of rank deficiency. We then analyze the outage probability (OP) of the proposed scheme over a Rayleigh fading channel. We analytically show that as long as the BH rate is greater than the individual data rate of one user, the OP of the proposed scheme decays like 1/SNR L at high SNR. This is in contrast to the existing scheme whose OP decays like 1/SNR. As the BH rate constraint approaches M times the data rate of one user, the performance of the proposed scheme is 10/L log 10 (L!) dB away from that of the full MIMO scenario at high SNR. We also develop a structured way to efficiently construct the preassigned LNC coefficient matrix that yields the optimized OP performance. Numerical results show that the proposed scheme has significantly improved performance over existing schemes.
BACKGROUND Although many attempts have been made to advance the treatment of complex anal fistula, it continues to be a difficult surgical problem. This study aimed to describe the novel technique of ...video-assisted anal fistula treatment (VAAFT) and our preliminary experiences using VAAFT with patients with complex anal fistula. MATERIAL AND METHODS From May 2015 to May 2016, 52 patients with complex anal fistula were treated with VAAFT at Yangpu Hospital of Tongji University School of Medicine, and the clinical data of these patients were reviewed. RESULTS VAAFT was performed successfully in all 52 patients. The median operation time was 55 minutes. Internal openings were identified in all cases. 50 cases were closed with sutures, and 2 were closed with staplers. Complications included perianal sepsis in 3 cases and bleeding in another 3 cases. Complete healing without recurrence was achieved in 44 patients (84.6%) after 9 months of follow-up. No fecal incontinence was observed. Furthermore, a significant improvement in Gastrointestinal Quality of Life Index (GIQLI) score was observed from preoperative baseline (mean, 85.5) to 3-month follow-up (mean, 105.4; p<0.001), and this increase was maintained at 9-months follow-up (mean, 109.6; p<0.001). CONCLUSIONS VAAFT is a safe and minimally invasive technique for treating complex anal fistula with preservation of anal sphincter function.
BACKGROUND Intestinal complications are a major cause of morbidity after colorectal cancer surgery. This study aimed to develop an effective nomogram for predicting risk of intestinal complications ...following colorectal cancer surgery. MATERIAL AND METHODS We retrospectively analyzed 1876 patients who underwent colorectal cancer surgery at Yangpu and Zhuji hospitals from January 2013 to October 2018. Intestinal complications were defined as intestinal obstruction, leakage or bleeding, or peritonitis within 30 days after surgery. A logistic regression model was used to identify the risk factors associated with postoperative intestinal complications, and a nomogram for intestinal complications was established. The predictive accuracy of the nomogram was assessed using area under the receiver operating characteristic curve (AUC) and calibration plot. RESULTS A total of 164 patients (8.7%) developed intestinal complications after colorectal cancer surgery; 35 (21.3%) of whom died in the postoperative period. Multivariate logistic analysis showed that male gender, history of abdominal surgery, preoperative intestinal obstruction/perforation, metastatic cancer, and lower level of hemoglobin and prognostic nutrition index were independent risk factors (P<0.05 for all). A nomogram was then constructed, and it displayed good accuracy in predicting postoperative intestinal complications with an AUC of 0.76. The calibration plot also showed an excellent agreement between the predicted and observed probabilities. CONCLUSIONS We constructed a nomogram based on clinical variables, which could provide individual prediction of postoperative intestinal complications with good accuracy.
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