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Objective To compare the diagnostic performance of PI-RADS v2.1 and PI-RADS v2 in the detection of clinically significant prostate cancer(csPCa) by Meta-analysis. Methods The major biomedical databases were searched (CNKI, CBM, Medline, and Embase) with the keywords "PIRADS v2.1" or "PI-RADS v2.1". The Quality Assessment of Diagnostic Accuracy Studies Tool v2 (QUADAS-2) was used to evaluate literature quality. Meta-analysis was performed using STATA17.0 and ReMan5.4 software. Forest plots were used to represent the sensitivity and specificity of PI-RADS v2.1 and PI-RADS v2 for each study. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were combined, and diagnostic performance was evaluated using asummary receiver operating characteristic curve (SROC). Subgroup analysis was performed on three covariables: tumor location, threshold, and the nationality of authors. Results A total of 12 studies were included, involving 3 158 patients and 3 243 lesions. Forall zones and the whole gland, PI-RADS v2.1 had a larger area under the SROC curve (AUC) for csPCa performance, compared with PI-RADS v2. Subgroup analysis: PI-RADS v2.1 also had a larger area under the SROC (AUC) to detect transitional zone csPCa. Different diagnostic thresholds: when a score of 4 was used for the threshold, PI-RADS v2.1 had the maximum area under SROC (AUC) for csPCa performance detection. Author nationality: Researches of PI-RADS v2.1 in Chinese authors had the largest area under the SROC (AUC) in detecting csPCa performance. Conclusion Compared with PI-RADS v2, the diagnostic performance of PI-RADS v2.1 in detecting csPCa is not obviously improved and overall specificity is still low.

With the continuous expansion of power grid scale, the phenomenon of subsynchronous oscillation caused by series compensated long-distance transmission system occurs frequently. Therefore, in order to analyze the deep reasons for the instability of the series compensated transmission system, based on the open-loop mode resonance theory, an open-loop mode resonance analysis method is proposed to analyze the subsynchronous oscillation caused by the series compensated transmission line. The small signal model of the external series compensated transmission line of permanent magnet synchronous generator (PMSG) farm is established, and the dynamic interaction between the series compensated line and the PMSG farm is studied through the open-loop mode resonance analysis method. The results show that the closed-loop stability of the system decreases when the open-loop subsynchronous oscillation mode dominated by series compensation is close to the open-loop subsynchronous oscillation mode dominated by wind farm in the complex plane. Using residual theory can successfully predict the position of closed-loop mode under the condition of open-loop mode resonance, while changing PMSG parameters or adjusting series compensation can avoid the occurrence of dynamic interaction. The correctness of the above theoretical analysis is verified by an example system in this paper. It is proved that there is a certain risk of instability when the PMSG farm transmits power through the series compensation transmission line, which can provide a reference for the parameter setting of the series compensation transmission system to a certain extent.

This article is a review of twentieth-century scholarship on agricultural water management in north China during the Qing dynasty. Water management encountered many difficulties because of natural and environmental factors. The author contends that in order to understand Qing politics, economics, and all aspects of society, knowledge of water management is crucial. The first part of the article describes the general history of water management. The second part discusses research in four different regions, covering topics such as development and change in agricultural water management. Studies reviewed include publications written in Chinese, English, and Japanese. [ABSTRACT FROM CONTRIBUTOR]

L-asparaginase (L-ASN) is widely applied in the treatment of malignant tumor and low-acrylamide food production, however, the low expression level hampers its application. Heterologous expression is an effective strategy to increase the expression level of target enzymes, and Bacillus is generally used as the host for efficient production of enzymes. In this study, the expression level of L-asparaginase in Bacillus was enhanced through optimization of expression element and host. Firstly, five signal peptides (SP SacC , SP AmyL , SP AprE , SP YwbN and SP WapA ) were screened, among which SP SacC showed the best performance, reaching an activity of 157.61 U/mL. Subsequently, four strong promoters (P43, P ykzA-P43 , P Ubay and P bacA ) from Bacillus were screened, and tandem promoter P ykzA-P43 showed the highest yield of L-asparaginase, which was 52.94% higher than that of control strain. Finally, three Bacillus expression hosts ( B. licheniformis Δ0F3 and BL10, B. subtilis WB800) were investigated, and the maximum L-asparaginase activity, 438.3 U/mL, was reached by B. licheniformis BL10, which was an 81.83% increase compared with that of the control. This is also the highest level of L-asparaginase in shake flask reported to date. Taken together, this study constructed a B. licheniformis strain BL10/P ykzA-P43 -SP SacC -ansZ capable of efficiently producing L-asparaginase, which laid the foundation for industrial production of L-asparaginase.

Due to the minimum free energy model, it is very important to predict the RNA secondary structure accurately and efficiently from the suboptimal foldings. Using clustering techniques in analyzing the suboptimal structures could effectively improve the prediction accuracy. An improved k-medoids cluster method is proposed to make this a better accuracy with the RBP score and the incremental candidate set of medoids matrix in this paper. The algorithm optimizes initial medoids through an expanding medoids candidate sets gradually. The predicted results indicated this algorithm could get a higher value of CH and significantly shorten the time for calculating clustering RNA folding structures.

Cancer gene expression data have the characteristics of high dimensionalities and small samples so it is necessary to perform dimensionality reduction of the data. Traditional linear dimensionality reduction approaches can not find the nonlinear relationship between the data points. In addition, they have bad dimensionality reduction results. Therefore a multiple weights locally linear embedding (LLE) algorithm with improved distance is introduced to perform dimensionality reduction in this study. We adopted an improved distance to calculate the neighbor of each data point in this algorithm, and then we introduced multiple sets of linearly independent local weight vectors for each neighbor, and obtained the embedding results in the low-dimensional space of the high-dimensional data by minimizing the reconstruction error. Experimental result showed that the multiple weights LLE algorithm with improved distance had good dimensionality reduction functions of the cancer gene expression data.

MicroRNA (miRNA) is a family of endogenous single-stranded RNA about 22 nucleotides in length. Through targeting 3' UTR of message RNA (mRNA), they play important roles in post-transcriptional regulatory functions. For further research of miRNA function, the identification of more miRNA positive targets is needed urgently. Aiming at the high-dimensional small sample data sets in miRNA target prediction, an algorithm of eliminating redundant features is proposed based on v-SVM in this paper, and classification and features selection are also fused. The algorithm of eliminating redundant features optimizes the combination of features, and then constructs the best features combination which can represent miRNA and targets interaction model. The prior parameter v (0 < u < or = 1) controls the compression proportion of data set and selects more distinguishing support vectors. Finally, the classifier model of miRNA target prediction is built. The unbiased assessment of the classifier is achieved with a completely independent test dataset. Experiment results indicated that in both classification recognition and generalization performance of miRNA targets predicition, this model was superior to the present machine learning algorithms such as miTarget, NBmiRTar and TargetMiner, etc.

Objective: To research the causes of postintubation vocal cord dyskinesia and its contributing factors., Method: The causes of vocal cord dyskinesia were confirmed by laryngoscope, three-dimensional spiral CT, stroboscope, and the analysis of therapy. The factors relevant to the causes of vocal cord dyskinesia were analysed based on the following elements: (1) the anatomic or pathological condition of patients or the technical skills of anesthetists. (2) emaciated or obese body and neck. (3) the age of patients. (4) the duration of endotracheal tube retention. (5) the types of operations. (6) anesthesia procedure., Result: Among 135 patients, 128 cases (94.81%) manifested arytenoid dislocation, 7 cases (5.19%) vocal cord paralysis. The study showed that the vocal cord dyskinesia associated with anatomic or pathological condition of patients and technical skills of anesthetists (with intubation difficulty) accounted for 76.30%. The patients with relative emaciated body or neck accounted for 90.62% in cases without intubation difficulty. Age had no significant analytical relationship with vocal cord dyskinesia. Prolonged intubation (endotracheal tube retention over 12 hours) was accounted for only 17.64%. The incidence of vocal cord dyskinesia was nearly 0.5% in patients underwent cardio-thoracic surgery, accounting for 59.26% of all the patients., Conclusion: There are two major causes of vocal cord dyskinesia: arytenoid dislocation and vocal cord paralysis, and the rate of vocal cord dyskinesia could be reduced by the improvement of technical skill of anesthetists and/or sufficient attention to the intubation condition of patients.

Gas chromatography (GC) coupled with dual columns and dual electron capture detectors (ECD) was established to determine 23 organochlorine pesticides in 5 soil and 5 sediment samples. Microwave assisted extraction and solid phase extraction with a Florisil column and sulfur cleanup with copper powder were used in sample pre-processing. Chromatographic analysis was performed on DB-XLB and DB-1701 capillary columns by internal standard method. This method showed good extraction efficiency, high sensitivity and good reproducibility. In the same linear range of 0.005 - 0.5 mg/L of 23 pesticides, the correlation coefficients were higher than 0.997. The average spiked recoveries were 50% - 119% with the relative standard deviations (RSDs) of 0.9% - 16.1% (n = 6) in 5 soil samples, and were 52% - 120% with RSDs of 0.3% - 28.4% ( n = 6) in 5 sediment samples, respectively. The detection limits were 0.000 05 -0.000 5 mg/kg. The results indicate that this method is suitable for the determination of the 23 organochlorine pesticides in soil and sediment samples.

Objective: To study the hemostatic effect of chemical constituents from Callicarpa nudiflora., Method: The chemical constituents were isolated and purified via silica gel and Sephadex LH-20 column chromatography. Their structures were determined on the basis of spectral analysis. prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and fibrinogen (FIB) of the constituents rabbit blood samples were tested with rabbit blood in vitro., Result: Eleven compounds were isolated and identified as two diterpenens: 7alpha-hydroxy sandaracopimaric acid (1), 16, 17-dihydroxy-3-oxophyllocladane (2). Two phenoic glycosides: acteoside (3), samioside(4). Three triterpenes: 2alpha, 3alpha, 24-trihydroxy-ursa-12-en-28-oic acid (5), 2alpha, 3alpha, 19alpha-trihydroxyursa-12-en-28-oic acid-28-0-beta-D-glucopyranosyl ester (6), and 2alpha, 3alpha, 19alpha, 23-tetrahydroxy-ursa-12-en-28-oic acid-28-0-beta-D-glucopyranosyl ester (7). Four flavones: rhamnazin (8), 5-Hydroxy-3, 7, 4'-trimethoxy-flavone (9) , 5-Hydroxy-3, 7, 3', 4'-tetramethoxyflavone (10), and luteoloside (11). All Compounds cannot significantly shorten the PT (P < 0.01), compounds 3, 4, 7, 10 can remarkedly increase APTT (P < 0.01), compound 5 can prolong the T( P < 0.01) obviously, and compound 8 can significantly increase the contents of FIB (P < 0.01)., Conclusion: Compounds 2, 4 and 10 were isolated from this genus for the first time, and compounds 1, 3, 5, 6, 7 and 9 had been isolated from this plant for the first time. The hemostatic effect of C. nudiflora may be related to the activation of the intrinsic blood coagulation system.

Objective: To study the alkaloids of Macleaya cordata., Method: The alkaloids were isolated and purified by various column chromatography as well as recrystallization. Their structures were identified by physico-chemical properties and spectral analysis., Result: Thirteen alkaloids were isolated and identified as 6-methoxy-dihydrosanguinarine (1), norsanguinarine (2), 6-acetonyl-dihyrochelerythrine (3), 6-acetonyl-dihyrosanguinnarine (4), sanguidimerine (5), chelidimerine (6), (+/-) -bocconarborine A (7), (+/-)-bocconarborine B (8), cryptopine (9), dihydrosanguinarine (10), dihydrochelerythrine (11), protopine (12), alpha-allocryptopine (13)., Conclusion: Compounds 2, 3, 5 - 9 were firstly isolated from the genus Macleaya and compound 1 was obtained from M. cordata for the first time.