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To effectively monitor the reliability of civil aircraft flap deflection angle, combined with the quick access recorder(QAR), the collaborative intelligent moving Kriging(CIMK) method is proposed by absorbing the Kriging model, decomposition and co-ordination strategy, equilibrium optimizer(EO), and moving least square(MLS). Among them, the decomposition coordination strategy is used to deal with the relationship between the flaps left and right deflection angles. MLS is employed to select effective modeling samples and solve the undetermined coefficients of Kriging model. EO method is applied to determine optimizing the local compact support region radius of MLS. Firstly, the fault reason for flap left-right asymmetry is analyzed to clarify the main characteristic parameters in QAR data. Secondly, combined with the QAR data of relevant influencing parameters, the civil aircraft flap deflection model(limit state function) is constructed by using CIMK. Then, the reliability and influence of civil aircraft flap deflection angle are analyzed by Monte Carlo(MC) sampling method. The results show that when the flap deflection angle is 3°, the reliability is 0.450 2, and the important factors affecting the flap deflection angle are Mach number, left angle of attack, right angle of attack, etc. Compared with the response surface method(RSM), Kriging, support vector machine(SVM), and back-propagation-artificial neural network(BP-ANN), the average absolute error accuracy of the proposed method is relative improved by 53.02%, 51.43%, 49.03%, and 44.04%, the average relative error accuracy is relative improved by 68.36%, 66.76%, 64.41%, and 62.64%, and the modeling efficiency is relative improved by 50.62%, 26.35%, and 43.01% respectively compared with Kriging, SVM and BP-ANN. When the number of simulations is 103, the analysis accuracy is relative improved by 8.82%, 7.25%, 6.22%, and 3.98% respectively.

Temperature is one of the important characteristic parameters of civil aircraft hydraulic system performance. To effectively realize the temperature monitoring of hydraulic system, the method of Kriging model based on atomic search (ASOKM) is proposed based on Kriging model and atomic search optimization (ASO) algorithm. Firstly, the temperature fault causes of hydraulic system are analyzed, and the fault logic diagram is established to clarify the characteristic parameters affecting the hydraulic system temperature. Then, combined with the quick access recorder (QAR) data, the modeling principle of ASOKM method is introduced. Finally, the effectiveness of the proposed ASOKM method is verified by the temperature monitoring analysis of domestic civil aircraft hydraulic systems. The results show that, in comparison with response surface method (RSM), Kriging, and back-propagation-artificial neural network (BP-ANN) models, the training and monitoring average absolute errors of the ASOKM method are lower, which is of higher accuracy, efficiency and robustness. The proposed ASOKM method can provide a reference for reliability analysis, fault diagnosis, and predictive maintenance of the hydraulic system.

Preventive maintenance is an indispensable part of civil aircraft operational support activities,and it is also the basis for ensuring the safe and economic operation of civil aircraft.As the first international general standard for preventive maintenance,S4000P provides preventive maintenance with a reasonable analysis method for the for-mulation of initial maintenance tasks throughout the life cycle,the analysis of unplanned maintenance tasks,and the optimization of initial maintenance tasks through operating data.In this paper the research status of preventive maintenance is combed,the S4000P standard is analyzed,and the analysis framework of civil aircraft preventive maintenance is established based on S4000P,which provides strong support for promoting the formulation and optimization process of civil aircraft preventive maintenance.

To explore the abandoned tailing of three typical heavy metal elements Cu, Pb, Zn in different pH value rainfall, rainfall intensity and rainfall duration comprehensive effect under the condition of leaching release the change rule, taking an abandoned tailings pond in Hanling town, Liaoyang county, Liaoning province as the object, prepared in the laboratory accords with the actual situation of different pollution degree of soil samples, the leaching test was carried out by using a large soil column to simulate rainfall. The results show that the lower the pH value, the higher the content of copper, lead and zinc in the leaching solution of each outlet, and the concentration of heavy metals in acidic leaching is higher than that in alkaline leaching and the cumulative release amount of three heavy metals is Zn>Pb>Cu. The heavy metal concentration in the bottom outlet is always the maximum, and the heavy metal concentration in the leachate from the overflow outlet of each soil column is not 0. Overall, the contents of heavy metals Cu, Pb and Zn in the leaching solution increased with the increase of rainfall intensity. Under the condition of acidic rainfall, the contents of copper, lead and zinc in the leaching solution also increased with the increase of leaching time, while under weak alkaline leaching conditions, it was just the opposite. [ABSTRACT FROM AUTHOR]

Lucian was an important rhetorician, satirist and sophist of Roman Empire in the second century AD. Scholars looked back on his religious thought from various angles and reached different conclusions. The key to having a true grasp of Lucian's religious thought is to understand his works as an integral whole. It can be seen that Lucian adopted the technique of ridicule and used philosophical concepts as an arm to attack sacrifice, criticize prophesy, and satire gods. He applied rigorous rational thinking to fustigate every vulnerable spot in traditional religion. However, Lucian was not an atheist. His criticism was not a complete break with traditional Greco-Roman religion or a stark denial of the necessity of belief, but an endeavor to enhance traditional religion to a new theology level and explore a theoretical foundation for traditional religious activities. [ABSTRACT FROM AUTHOR]

The continuous discharge of pharmaceutical and personal care products (PPCPs) into aquatic environment and their potential threaten to ecological environment or human health has received more and more attention all over the world. Algae are primary producers in aquatic environment and play an important role in ecosystem balance and stabilization. In this review, the concentrations of PPCPs in natural waters from different countries and regions are introduced to demonstrate their characteristics of pollution in aquatic environment. Furthermore, we reviewed some progresses on the toxicity, bioaccumulation and ecological risk of PPCPs. We introduced the toxicity effect and mechanism of PPCPs to algae, the bioaccumulation of PPCPs in algae, as well as the ecological risks of PPCPs in surface water. The review will provide references for development of PPCPs related criteria and assessment of ecological risks in aquatic environment.

Objective: To compare the short-term outcomes between robotic and laparoscopic radical total gastrectomy in gastric cancer patients with BMI index ≥24 kg/m 2 ., Method: Clinical data of 93 gastric cancer patients who underwent robotic and laparoscopic radical total gastrectomy at PLA General Hospital from April 2016 to April 2017 were retrospectively analyzed. The retrospective cohort study was adopted., Inclusion Criteria: preoperatively definite diagnosis of primary gastric cancer by endoscopy and biopsy; preoperative BMI ≥24 kg/m 2 ; no previous abdominal surgery; no previous chemotherapy and radiotherapy; no distant metastasis or invasion into adjacent organs before operation or during operation; receiving radical gastrectomy; Roux-en-Y reconstruction of digestive tract in open procedure. According to approaches of minimally invasive surgery, 24 patients underwent robotic surgery and 69 underwent laparoscopic surgery. The intraoperative parameters (overall operative time, pneumoperitoneal time, open procedure time, intraoperative blood loss, transfusion rate, number of total retrieved lymph nodes and metastatic lymph nodes) and postoperative parameters (drainage in the first postoperative day, the first defecation time, morbidity of postoperative complication and hospital stay) were compared between two groups. Correlation of the above parameters were analyzed., Results: Of 93 patients, 77 were male and 16 female with an average age of (60.0±10.6) years. The average BMI was (26.8±1.3) kg/m 2 in whole patients, (26.9±1.6) kg/m 2 in robotic group and (26.8±1.7) kg/m 2 in laparoscopic group. No significant differences in age, gender, BMI, preoperative ASA class, postoperative pathological findings and clinical classification were observed between two groups, which made short-term parameters between two groups comparable. The robotic group had a significantly longer overall operative time [(301.2±68.9) minutes vs. (247.3±59.6) minutes, P=0.000], longer open procedure time [(141.5±26.3) minutes vs. (92.5±36.7) minutes, P=0.029] and higher cost than laparoscopy group[(17.5×10 4 ± 9.7×10 4 ) yuan vs. (10.0×10 4 ± 2.3×10 4 ) yuan, P=0.001]. Pneumoperitoneal operative time, intraoperative blood loss, transfusion rate, number of total retrieved lymph nodes, number of harvested metastatic lymph nodes and postoperative short-term efficacy were similar between the two groups (all P>0.05). In robotic group, pneumoperitoneal operative time was positively correlated with overall operative time (r=0.708, P=0.010); total cost was positively correlated with postoperative hospital stay (r=0.493, P=0.000) and open procedure time was negatively correlated with the first defecation time (r=-0.962, P=0.038). In laparoscopy group, total cost was positively correlated with overall operative time (r=0.411, P=0.046), drainage volume in the first postoperative day was positively correlated with the number of total dissected lymph node (r=0.540, P=0.006), postoperative hospital stay was positively correlated with intraoperative blood loss (r=0.574, P=0.003), total cost was positively correlated with intraoperative blood loss and hospital stay (r=0.609, P=0.002; r=0.865, P=0.000), drainage volume in the first postoperative day was positively correlated with BMI (r=0.533, P=0.007)., Conclusion: For gastric cancer patients with BMI ≥24 kg/m 2 , robotic radical total gastrectomy is associated with longer operative time and higher cost, but is less vulnerable to the change of BMI and more in favor of the realization of enhanced recovery after surgery (ERAS) than laparoscopic radical total gastectomy.

Objective: To determine the oxidative stress level in peripheral blood of vanadium-exposed workers, as an indication of population health effect of vanadium on human neurobehavioral system., Methods: 86 vanadium-exposed workers and 65 non-exposed workers were recruited by cluster sampling. A questionnaire was administered to collect demographic and occupational exposure information. Serum activity of superoxide dismutase (SOD), inducible nitric oxide synthase (iNOS) and malonaldehyde (MDA) contents were detected by kit assay. The differences in oxidative stress level between vanadium-exposed and non-exposed workers were compared., Results: Vanadium-exposed workers had higher levels of MDA contents than the controls. The total superoxide dismutase(T-SOD) activity in vanadium-exposed workers was significantly lower than that in the controls, which was associated with lowered levels of manganese superoxide dismutase (Mn-SOD) activity. No changes in serum levels of cupro-zinc superoxide dismutase (CuZn-SOD) was found in vanadium-exposed workers. No difference in iNOS activity was found between vanadium-exposed workers and controls., Conclusion: Vanadium exposure increases free radical production in serum and reduces antioxidant capacity. But the relationship between vanadium exposure and iNOS damage remains uncertain.

Objective: To analyze the impact of mRNA expression of oral fluoropyrimidine (S-1) metabolism on treatment outcomes in locally advanced gastric cancer patients on preoperative S-1 oxaliplatin-based chemotherapy., Methods: Between June 2012 and March 2013, 32 patients with preoperative AJCC stage II-III gastric cancer patients were enrolled. They received S-1 (80 mg·m⁻² × d⁻¹, days 1-14) and oxaliplatin (130 mg/m², day 1) every 3 weeks and subsequently underwent gastrectomy with D2 lymphadenectomy. Paired tumor and normal fresh frozen tissues were collected to evaluate the mRNA levels of thymidylate synthase (TS), thymidine phosphorylase (TP), dihydropyrimidine dehydrogenase (DPD) and OPRT with quantitative reverse transcription(RT) -PCR., Results: Among them, 21 (65.6%) patients had clinical tumor response and histological response occurred in 10 (31.3%) patients. Quantitative RT-PCR results showed that OPRT mRNA expression was significantly higher in clinical tumor responders than non-responders (3.95 ± 0.81 vs 1.79 ± 0.64, P = 0.005). Diffuse-type gastric cancer patients (n = 22) demonstrated higher OPRT expression levels than intestinal-type(n = 10) ones (2.54 ± 0.75 vs 1.49 ± 0.56, P = 0.014). The mRNA expressions of TS and TP in gastric cancer tissues with lymph node (LN) metastasis (n = 13) were significantly higher than those in gastric cancer tissues without LN metastasis (n = 19, both P < 0.05) .Similar results were not found for comparing dihydropyrimidine dehydrogenase expression levels (all P > 0.05)., Conclusion: OPRT, TS and TP may become potential predictive biomarkers in advanced gastric cancer patients on oral fluoropyrimidine (S-1)-based chemotherapy.

Objective: To study the timing of infusion of hypertonic saline solution (HTS) to exert its protective effect on intestinal barrier function in rabbits with intestinal ischemia/reperfusion (I/R) injury., Methods: Seventy-two rabbits were randomly divided into four groups (each n=18): sham operation group, I/R group, HTS pretreatment group and HTS delayed treatment group. The intestinal I/R models were produced by blocking the superior mesenteric artery (SMA) for 1 hour followed by release of the SMA. 7.5% HTS (6 ml/kg) was infused in HTS pretreatment group 5 minutes before release of SMA, and HTS was infused in delayed treatment group 2 hours after reperfusion and finished in 5 minutes. Levels of D-lactic acid (D-Lac), lipopolysaccharide (LPS), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) were determined before ischemia and 2, 4, 6 hours after reperfusion. The levels of malonaldehyde (MDA), superoxide dismutase (SOD), myeloperoxidase (MPO) in intestinal tissues of 8 rabbits in each group were measured at 6 hours after reperfusion. Meanwhile the intestinal morphological changes were observed, and the Chin score, which reflected the degree of injury to intestinal mucosa was calculated., Results: Compared with sham operation group, D-Lac, LPS, TNF-α and IL-10 in I/R group were significantly increased from 2 hours after reperfusion (D-Lac: 18.91 ± 3.46 mg/L vs. 3.92 ± 0.61 mg/L, LPS: 869 ± 85 EU/L vs. 422 ± 27 EU/L, TNF-α: 23.80 ± 4.22 μg/L vs. 3.65 ± 0.51μg/L, IL-10: 8.90 ± 2.75 μg/L vs. 2.53 ± 0.80 μg/L, all P<0.05); MDA, MPO and Chiu score were significantly increased (MDA: 398 ± 28 nmol/mg vs. 173 ± 20 nmol/mg, MPO: 465 ± 52 mU/mg vs. 183 ± 25 mU/mg, Chiu score: 4.36 ± 0.52 vs. 0.38 ± 0.22, all P<0.05), while SOD decreased significantly (35 ± 9 U/mg vs. 52 ± 8 U/mg, P<0.05). Compared with I/R group, the levels of D-Lac, LPS, TNF-α, MDA, MPO and Chiu score in HTS pretreatment group were lower (D-Lac: 11.45 ± 0.92 mg/L vs. 18.91 ± 3.46 mg/L, LPS: 455 ± 114 EU/L vs. 869 ± 85 EU/L, TNF-α: 10.32 ± 2.11 μg/L vs. 23.80 ± 4.22 μg/L, MDA: 221 ± 21 nmol/mg vs. 398 ± 28 nmol/mg, MPO: 271 ± 20 mU/mg vs. 465 ± 52 mU/mg, Chiu score: 1.69 ± 0.24 vs. 4.36 ± 0.52, all P<0.05), while IL-10 and SOD were significantly increased (IL-10: 14.54 ± 2.02 μg/L vs. 8.90 ± 2.75 μg/L, SOD: 90 ± 14 U/mg vs. 35 ± 9 U/mg, both P<0.05). The levels of the above indexes in HTS delayed treatment group were similar to I/R group, and the effect was lower than that in HTS pretreatment group., Conclusions: HTS had the protective effect on intestine suffering from I/R injury. But the protective effect was time dependent, and early treatment shows protective effect.

Diatom, due to its high sensitivity to environmental change, is one of the bio-indicators of aquatic ecosystem health, and some typical diatom species have been applied to indicate the heavy metals pollution of water body. With the focus on the surface water heavy metals pollution, this paper reviewed the research advances in the toxic effect of heavy metals pollution on diatom, biosorption and bioaccumulation of heavy metals by diatom, ecological adaptation mechanisms of diatom to heavy metals pollution, and roles of diatom as bio-indicator and in ecological restoration of heavy metals pollution. The growth tendency of diatom and the morphological change of frustule under heavy metals pollution as well as the differences in heavy metals biosorption and bioaccumulation by diatom, the ecological adaptation mechanisms of diatom on heavy metals surface complexation and ion exchange, and the roles of diatom as bio-indicator and in ecological restoration of heavy metals polluted water body were also discussed. This review could provide scientific evidences for the prevention of aquatic ecosystems heavy metals pollution and related early warning techniques.

Objective: To study the circadian patterns of the incidence of upper gastrointestinal bleeding (UGIB) and its relationship with climatic factors in Beijing., Methods: We searched all UGIB records from August 1, 2005 to July 31, 2007 from Beijing Emergency Center and tracked the meteorological data during the same period. The variation of the incidence of UGIB was compared based on day, month, and season. The relation between climatic factors and the incidence of UGIB was also analyzed., Results: Totally 2 580 patients, including 1 888 males (73.2%) and 692 females (26.8%) were included in the study. The mean age was significantly different between males and females [(53.3 +/- 20.4) years vs. (63.3 +/- 20.7) years, P < 0.05]. The occurrence of UGIB were significantly different among different seasons (chi2 = 49.82, P < 0.01), months (chi2 = 83.43, P < 0.01), and hours (chi2 = 126.79, P < 0.01). UGIB cases were presented more frequently in winter and spring, especially in January. More UGIB cases were presented at night, especially from 8 pm to midnight. Partial correlation test showed that the incidence of UGIB significantly correlated with temperature (r = -0.3785, P = 0.001) and barametric pressure (r = -0.3002, P = 0.011). No correlation was found between UGIB incidence and wind speed (P = 0.086) and relative humidity (P = 0.971)., Conclusions: The incidence of UGIB varies in different months and seasons in Beijing. Its climate-related risk factors may include temperature and barametric pressure, but not include relative humidity and wind speed.

Objective: To explore the clinical features of respiratory failure secondary to hypothyroidism., Method: We retrospectively analyzed the clinical data of 4 patients with respiratory failure secondary to hypothyroidism., Results: Respiratory failure secondary to hypothyroidism usually happened in the aged patients, presenting as myxedema, disturbance of consciousness, anemia, and hyponatrium. Respiratory symptoms were rare. Type II respiratory failure might occur as disease progressed. The clinical presentation of hypothyroidism was atypical and easily neglected. The hypoxia and hypercapnia ameliorated after thyroid hormone therapy., Conclusion: Hypothyroidism is a rare reason of respiratory failure. The prognosis is good after hormone therapy and mechanical ventilation.