Simulation and prediction of monthly accumulated runoff,based on several neural network models under poor data availability

Most previous research on areas with abundant rainfall shows that simulations using rainfall-runoff modes have a very high prediction accuracy and applicability when using a back-propagation(BP), feed-forward, multilayer perceptron artificial neural network(ANN). However, in runoff areas with relatively low rainfall or a dry climate, more studies are needed. In these areas—of which oasis-plain areas are a particularly good example—the existence and development of runoff depends largely on that which is generated from alpine regions. Quantitative analysis of the uncertainty of runoff simulation under climate change is the key to improving the utilization and management of water resources in arid areas. Therefore, in this context, three kinds of BP feed-forward, three-layer ANNs with similar structure were chosen as models in this paper.Taking the oasis–plain region traverse by the Qira River Basin in Xinjiang, China, as the research area, the monthly accumulated runoff of the Qira River in the next month was simulated and predicted. The results showed that the training precision of a compact wavelet neural network is low; but from the forecasting results, it could be concluded that the training algorithm can better reflect the whole law of samples. The traditional artificial neural network(TANN) model and radial basis-function neural network(RBFNN) model showed higher accuracy in the training and prediction stage. However, the TANN model, more sensitive to the selection of input variables, requires a large number of numerical simulations to determine the appropriate input variables and the number of hidden-layer neurons. Hence, The RBFNN model is more suitable for the study of such problems. And it can be extended to other similar research arid-oasis areas on the southern edge of the Kunlun Mountains and provides a reference for sustainable water-resource management of arid-oasis areas.

Realization of the Linear Tree that Corresponds to a Fundamental Loop Matrix

Graph realization from a matrix is an important topic in network topology. This paper presents an algorithm for the realization of a linear tree based on the study of the properties of the number of the single-link loops that are incident to each tree branch in the fundamental loop matrix Bf. The proposed method judges the pendent properties of the tree branches, determines their order one by one and then achieves the realization of the linear tree. The graph that corresponds to Bf is eventually constructed by adding links to the obtained linear tree. The proposed method can be extended for the realization of a general tree.

Nonalcoholic steatohepatitis critically rewires the ischemia/ reperfusion-induced dysregulation of cardiolipins and sphingolipids in mice

Background:Lipid dysregulation plays a fundamental role in nonalcoholic steatohepatitis(NASH),which is an emerging critical risk factor that aggravates hepatic ischemia/reperfusion(I/R)injury.However,the specific lipids that mediate the aggressive I/R injury in NASH livers have not yet been identified.Methods:The mouse model of hepatic I/R injury on NASH was established on C56B/6J mice by first feeding the mice with a Western-style diet to induce NASH,then the NASH mice were subjected to surgical procedures to induce hepatic I/R injury.Untargeted lipidomics were performed to determine hepatic lipids in NASH livers with I/R injury through ultra-high performance liquid chromatography coupled with mass spectrometry.The pathology associated with the dysregulated lipids was examined.Results:Lipidomics analyses identified cardiolipins(CL)and sphingolipids(SL),including ceramides(CER),glycosphingolipids,sphingosines,and sphingomyelins,as the most relevant lipid classes that characterized the lipid dysregulation in NASH livers with I/R injury.CER were increased in normal livers with I/R injury,and the I/R-induced increase of CER was further augmented in NASH livers.Metabolic pathway analysis revealed that the enzymes involved in the synthesis and degradation of CER were highly upregulated in NASH livers with I/R injury,including serine palmitoyltransferase 3(Sptlc3),ceramide synthase 2(Cers2),neutral sphingomyelinase 2(Smpd3),and glucosylceramidase beta 2(Gba2)that produced CER,and alkaline ceramidase 2(Acer2),alkaline ceramidase 3(Acer3),sphingosine kinase 1(Sphk1),sphingosine-1-phosphate lyase(Sgpl1),and sphingosine-1-phosphate phosphatase 1(Sgpp1)that catalyzed the degradation of CER.CL were not affected by I/R challenge in normal livers,but CL was dramatically reduced in NASH livers with I/R injury.Consistently,metabolic pathway analyses revealed that the enzymes catalyzing the generation of CL were downregulated in NASH-I/R injury,including cardiolipin synthase(Crls1)and tafazzin(Taz).Notably,the I/R-induced oxidative stress and cell death were found to be aggravated in NASH livers,which were possibly mediated by the reduction of CL and accumulation of CER.Conclusions:The I/R-induced dysregulation of CL and SL were critically rewired by NASH,which might potentially mediate the aggressive I/R injury in NASH livers.