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The influencing factors of pipeline corrosion are many and complex, so establishing an accurate prediction model of pipeline corrosion rate is the key to evaluate pipeline safety. Aiming at the defects of the traditional Elman neural network (ENN) model, which is easy to fall into the minimum value and has weak generalization ability, a new ENN model based on improved reptile search algorithm (introducing Circle chaos map and combined hunting strategy with whale optimization algorithm) was proposed, and the effectiveness of the new model was verified by the measured results of pipeline corrosion rate. The prediction results of two examples show that the mean absolute percentage error of the improved new model is 0. 547 6% and 0. 783 1% respectively, and its prediction accuracy is obviously higher than that of the traditional ENN model. The new model can optimize the weights and thresholds in the prediction process, so it is helpful to improve the prediction accuracy of the traditional model. [ABSTRACT FROM AUTHOR]

Copyright of Mechanical & Electronic Control Engineering is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mechanical & Electronic Control Engineering is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract BACKGROUND: Myocardial ischemia is one of the main causes of cardiac function impairment after myocardial infarction. Notch is involved in the process of angiogenesis, but whether Notch intracellular domain (NICD)/Hes1 is involved in myocardial angiogenesis after myocardial infarction has not been studied. OBJECTIVE: To study the effect of NICD /Hes1 pathway on cardiac function and angiogenesis in the ischemic myocardium of myocardial infarction mice with the aid of RO4929097, a Notch γ secretase inhibitor. METHODS: C57BL/6 mice were randomized into sham, model and RO4929097 groups, with 10 mice in each group. Myocardial infarction model was established in the latter two groups by ligating the left anterior descending coronary artery of C57BL/6 mice. Mice in the RO4929097 group were administered RO4929097 by gavage at the dose of 10 mg/(kg·d) on day 2 after surgery, and those in the sham and model groups were given an equal volume of saline by gavage for 20 days. On day 21, mice were examined by ultrasound for left ventricular ejection fraction, Matson staining for myocardial infarct area and pathohistological changes and immunofluorescence for CD31 in ischemic myocardium. Enzyme-linked immunofluorescence was used to detect the levels of serum vascular endothelial growth factor and basic fibroblast growth factor. Western blot assay was used to detect the expression of hypoxia-inducible factor 1α, cardiotrophin 1, NICD and Hes1 in myocardial tissue. RESULTS AND CONCLUSION: The left ventricular ejection fraction value in the model group was significantly lower than that in the sham group (P < 0.001), while compared with the model group, the left ventricular ejection fraction value was significantly lowered in the RO4929097 group (P < 0.05). Masson staining revealed an significantly increased infarct size in the model group and RO4929097 group compared with the sham group (P < 0.001) as well as an obviously increased infarct size in the RO4929097 group compared with the model group (P < 0.05). The mean absorbance value of CD31 significantly increased in the model group compared with the sham group (P < 0.001) and significantly decreased in the RO4929097 group compared with the model group (P < 0.001). Compared with the sham group, the levels of serum vascular endothelial growth factor and basic fibroblast growth factor significantly increased in the model and RO4929097 groups (P < 0.05); and the levels of these two factors were significantly higher in the RO4929097 group than the model group (P < 0.01). The protein expression levels of hypoxia-inducible factor 1α, cardiotrophin 1 were significantly increased in the model group compared with the sham group (P < 0.01) but decreased in the RO492909 group. The protein expression of NICD significantly increased in the model group compared with the sham group (P < 0.01) but decreased in the RO492909 group compared with the model group (P < 0.01). Compared with the sham group, the level of Hes1 was significantly decreased in the RO492909 group (P < 0.05). To conclude, RO4929097 may decrease NICD/Hes1 expression by inhibiting Notchγ secretase activity, thereby reducing ischemic myocardial revascularization and decreasing left ventricular ejection fraction in mice with myocardial infarction. [ABSTRACT FROM AUTHOR]

Copyright of Geology & Resources is the property of Geology & Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the emergence of a large number of new network applications? traditional network technologies cannot meet the requirements of current applications on bandwidth，latency，error rate and etc. In this case，IP over DWDM optical Internet has become a research hotspot with unique characteristics and advantages. In this paper ？ we put forward a heterogeneous multicast routing mechanism for IP over DWDM optical Internet based on the species evolutionary algorithm. The scheme employs the theory o£ probability to solve the uncertainty problem o£ networks，state parameters information. We adopt the fuzzy method to support flexible QoS and design a bandwidth pricing method which considers the benefits o£ both users and network service providers. Simulation results show that the proposed mechanism can achieve good comprehensive performance indexes and effectively solve the QoS heterogeneous multicast routing problem in the IP over DWDM optical Internet. [ABSTRACT FROM AUTHOR]