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Background: long noncoding RNAs (lncRNAs) have attracted attention recently. However, many inconsistencies frequently appeared for the early diagnosis of digestive tract cancers (DTCs). We performed this meta-analysis to describe the diagnostic performance of lncRNAs in the discrimination of DTCs. Methods: data were extracted from PubMed, Web of Science, Embase, and Cochrane Library. Their quality was evaluated using the revised Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Such parameters as sensitivity and specificity were included for pooled analyses. The STATA 12.0 and Meta-Disc 1.4 software packages were used to perform the statistical analysis. Results: sixty-nine papers were included in this meta-analysis. The pooled analysis of DTCs showed that lncRNAs had a sensitivity of 0.78 and a specificity of 0.80. The area under the summary ROC curve (AUC) was 0.86. For gastric cancer (GC), the pooled sensitivity and specificity were 0.77 (95 % CI: 0.72-0.81) and 0.75 (95 % CI: 0.71-0.79), respectively, and the AUC was 0.83. For colorectal cancer (CRC), these three parameters were 0.82 (95 % CI: 0.76-0.86), 0.84 (95 % CI: 0.79-0.88), and 0.90, respectively. For esophageal cancer (EC) sensitivity was 0.74 (95 % CI: 0.67-0.80) and specificity reached 0.86 (95 % CI: 0.72-0.93), with an AUC of 0.82. Conclusions: LncRNAs show potential diagnostic value for discrimination between DTCs.

Purpose A growing number of researches manifest that DNA methylation has been considered as biomarker for the prognosis of bladder cancer (BC). However, the results are still in a discrepancy. Materials and methods This meta-analysis was conducted in accordance with PRISMA guidelines. Studies evaluating the practicability of methylated DNA as a prognostic marker for BC were thoroughly searched via the PubMed, Web of science and the Cochrane Library databases from January 1st, 2000 to May 5th, 2018. The association between DNA methylation and overall survival (OS) and progression-free survival (PFS) was analyzed. Hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated to assess the correlation between methylated DNA and prognostic value in BC by using multivariate survival analysis. Results Nineteen studies were included. Patients with methylated DNA had poorer OS, compared with those with unmethylated DNA, the combined HR was 2.766 (95%CI: 2.099–3.806). Simultaneously, methylated DNA was considerably associated with shorter PFS (HR = 2.872, 95%CI: 1.971–4.185). Furthermore, DNA methylation had a significant association with gender (male vs female: OR = 1.486, 95% CI = 1.090–2.025), grade (3 vs 1–2: OR = 3.153, 95% CI = 2.006–4.955), tumor diameter (≤3 cm vs >3 cm: OR = 0.408, 95% CI = 0.277–0.602), number of tumors (single vs multiple: OR = 0.683, 95% CI = 0.501–0.932), stage (Ta vs T1: OR = 0.472, 95% CI = 0.342–0.654), (Ta-T1 vs T2-T4: OR = 0.338, 95% CI =0.210–0.543). Conclusions DNA methylation was negatively correlated with the prognosis of BC patients and might become a promising biomarker.

To avoid large currents caused by closing-loop operations in medium-voltage distribution grids, it is necessary to develop an effective method for rapid and accurate calculation of the closing-loop currents. In this paper, theoretical analysis is conducted to obtain the typical equivalent circuit for the calculation and analysis of the typical 10kV closing-loop system in Shanghai Grid. Three methods considering both the calculation complexity and the result accuracy, namely detailed power flow analysis method, simplified power flow analysis method and approximate formula method are proposed based on the typical equivalent closing-loop system. In the case study, the closing-loop currents of 10kV distribution grid of Shanghai under various operation scenarios are calculated with the three methods respectively, and the influence of the load levels and transformers’ tap positions on the closing-loop currents are analyzed in accordance with the practical requirements of dispatching. The validity of the three methods is confirmed through comparison of the calculation results with full-network simulation results through BPA software. Furthermore, the convergence, accuracy and practical applicability of the three methods are compared, thus to provide a feasible and reliable decision basis for practical distribution grids dispatching.

This study is a meta-analysis and aims to determine the value of urinary survivin for detecting bladder cancer (BC) on the basis of preceding statistical performance and to compare their diagnostic value. Considering that the urinary survivin data were from both RNA and protein levels, the key words “bladder cancer” AND “survivin” and “bladder cancer” AND “survivin RNA” were used; and PubMed, Web of Science, and Cochrane Library were systematically searched to identify relevant articles. The methodological quality of each study was assessed by QUADAS-2. Data were analyzed by STATA 12.0 and Meta-disc v.1.4 software package. A random-effects model was used and subgroup analysis was carried out to identify possible sources of heterogeneity. Nine articles for survivin protein test with 789 patients and 684 controls, and 12 articles for survivin RNA test with 880 patients and 922 controls were identified. The results showed that the pooled sensitivity was 0.79 (95% CI 0.73, 0.84), specificity was 0.87 (95% CI 0.79, 0.92) of the survivin protein test for bladder cancer, and the sensitivity and specificity was 0.84 (95% CI 0.79, 0.88) and 0.94 (95% CI 0.89, 0.97) of the survivin RNA test. The AUC of the two approaches was 0.89 (95% CI 0.86, 0.91) and 0.94 (95% CI 0.92, 0.96), respectively. The survivin protein and survivin RNA both had great potential as biomarkers for BC detection, and survivin RNA showed higher accuracy than survivin protein on BC diagnosis.

Programmed death‐1 (PD‐1) plays an important role in protecting against inflammation and myocyte damage in T‐cell‐mediated myocarditis. To understand whether fibrinogen‐like protein‐2 (FGL2) can affect the role of the PD‐1/PD‐L1 pathway in experimental autoimmune myocarditis (EAM), we investigated cardiac function in EAM rats over‐expressing FGL2. Over‐expression of FGL2 significantly decreased PD‐1 and deteriorated cardiac function in rats with autoimmune myocarditis. Histopathology revealed increased inflammatory cell infiltrate in EAM‐FGL2 rats compared with the control groups (EAM, EAM‐GFP and NC). Notably, transcription factor forkhead box P3 (Foxp3) and retinoic acid‐related orphan receptor γt (ROR γt) protein and mRNA levels were statistically (P

As substantial power is imported into Shanghai Grid through four HVDC systems, the operation characteristics of multi-infeed receiving-end system have emerged in Shanghai Grid. The intensive interactions between HVDC system and AC grid may aggravate the risk of cascading as well as the capability of the grid to withstand significant disturbances. In this paper, simulation of HVDC system response upon fault occurrence in AC system is performed for Shanghai Grid with the maximum power import through four HVDC transmission systems. The risk of AC grid's instability due to commutation failures and blockings of HVDC systems is investigated. Quantitative assessment of system voltage stability margin is conducted for the grid under simultaneous blockings of multiple HVDC systems. The overall security and stability risk attributed to the interactive influence between AC and DC grid is evaluated for Shanghai Grid under extreme contingencies.

As multi-infeed HVDC systems are integrated into East China Grid, the operation characteristics and concerns of the grid have changed remarkably. Due to substantial power import through HVDC systems, a large quantity of local generators in the receiving-end grid have to be shut down. The resulting aggravated shortage of dynamic reactive power reserve exacerbates the capability of the grid to withstand significant disturbances. Commutation failures and blockings of multi-infeed HVDC systems may even instigate voltage instability in the receiving-end grid. Synchronous condensers are projected to be installed at HVDC converting stations so as to provide dynamic reactive power support and to improve voltage control performance in East China Grid. Simulation and comparative analysis is performed in this paper to investigate the influence of integration of synchronous condensers on various aspects of system performance involving short-circuit current, voltage stability and transient stability of the grid as well as commutation failures of HVDC systems. The comprehensive analysis results are expected to provide technical reference for allocation of synchronous condensers and determination of the appropriate parameters of the equipment.

The considerably uneven distribution of power flow on 500kV Anhui-Jiangsu cross province interface during peak hours may contribute to overload conditions in case of out ages on one of the four transmission lines of this interface. Ex port of electric power from Anhui province through this inter face to Yangze Delta load center is restricted to 4800MW. Installation of thyristor-controlled phase shifting transformer (TCPST) on each of the 500kV cross province transmission lines from Dangtu substation to Huifengshan substation is reviewed to be effective solution for interface power flow control under various possible grid operation conditions. This paper evaluates the application effect of the demonstration project, which involves power flow control impact on the interface and neighboring sys tem, short circuit current limiting effect with respect to the impedance of TCPST under varying phase shifting angle as well as system stability performance related issues. The evaluation is expected to provide theoretic basis for the implementation of the demonstration project.

Fujian provincial grid was connected into East China grid through two parallel tie lines of 500kV in 2002. Out-of-step oscillation may occur between Fujian Province Grid and East China grid under the critical contingencies. System separation devices have been installed on 500kV tie-lines between Fujian grid and East China grid to maintain system stability. As the newly built UHV Binjin DC transmission system was projected to come in service in 2014, power injected into East China grid through the system was gradually increased to its full capacity in accordance with the implementation of the project by three stages. The characteristics of out-of-step oscillation between Fujian grid and East China grid may be altered due to the significant changes involving tie lines, reinforcement and reconfiguration of local system as well as the scale of power injection. To investigate the characteristics of out-of-step oscillation, extreme contingencies contributing to out-of-step oscillation are identified based on the analysis of the practical grid operation. For each stage of Binjin transmission project, the center of out-of-step oscillation is determined through the simulation analysis of the oscillation characteristics for East China grid. The applicability of the existing system separation devices is evaluated, and system separation strategy is then reviewed for East China grid to accommodate the operation of UHV Binjin DC transmission project.

Conduction behavior of n-MOSFET capacitors with ultra-thin oxides was investigated before and after constant current stress. It was found that stress induced leakage current (SILC) strongly depends on the low sense voltages. Conduction mechanism of the low voltage SILC (LV-SILC) was analyzed systematically, based on the assumption that the LV-SILC is due to interface trap-assisted tunneling process (ITAT). Using the LV-SILC as a probe, generation of interface defects was investigated. Defects at both interfaces of anode and cathode are involved in ITAT process. Defect generation is a nonlinear process. Dependence of defect generation rate as a function of stress time could be used as a detector of oxide breakdown.

As an electric fault occurs, a strong magnetic force exerted on three-phase overhead power lines may bring them in close proximity or in contact with one another, causing a subsequent fault. A computer simulation has been developed for the analysis of the magnetically induced subsequent fault and presented in the authors’ earlier work. It has been found that one important factor affecting the probability of the subsequent fault is the power line configurations. In this paper, we present a numerical technique for determining the maximum span length of the power lines based on consideration of eliminating the magnetically induced subsequent fault. Various power line constructions corresponding to different fault current levels are investigated. The results presented in this paper are anticipated to be useful for a utility in long span design.

As an electric fault occurs, a strong magnetic force and torque exerted on three-phase overhead power line conductors would make them to swing and may bring them to close proximity or in contact with one another, causing a subsequent fault. A computer simulation has been developed for the analysis of the magnetically induced subsequent fault and presented in the authors’ earlier work, for level spans. However, the power line construction in mountainous areas requires the use of inclined spans. In this paper, we present an analysis of the magnetically induced subsequent fault in inclined-span utility line topologies. This analysis is in a transformed coordinate system, making use of electromagnetic theory and fundamental laws of mechanics as well as numerical methods. Power lines with different inclined angles are studied and the numerical results are compared with that for level spans. To validate the accuracy of the numerical results, they are checked with the energy conservation law requirement.