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The subduction model of the Neo-Tethys during the Early Cretaceous has always been a controversial topic, and the scarcity of Early Cretaceous magmatic rocks in the southern part of the Gangdese batholith is the main cause of this debate. To address this issue, this article presents new zircon U–Pb chronology, zircon Hf isotope, whole-rock geochemistry and Sr–Nd isotope data for the Early Cretaceous quartz diorite dykes with adakite affinity in Liuqiong, Gongga. Zircon U–Pb dating of three samples yielded ages of c. 141–137 Ma, indicating that the Liuqiong quartz diorite was emplaced in the Early Cretaceous. The whole-rock geochemical analysis shows that the Liuqiong quartz diorite is enriched in large-ion lithophile elements (LILEs) and light rare-earth elements (LREEs) and is depleted in high-field-strength elements (HFSEs), which are related to slab subduction. Additionally, the Liuqiong quartz diorite has high SiO2, Al2O3 and Sr contents, high Sr/Y ratios and low heavy rare-earth element (HREE) and Y contents, which are compatible with typical adakite signatures. The initial 87Sr/86Sr values of the Liuqiong adakite range from 0.705617 to 0.705853, and the whole-rock ϵNd(t) values vary between +5.78 and +6.24. The zircon ϵHf(t) values vary from +11.5 to +16.4. Our results show that the Liuqiong adakite magma was derived from partial melting of the Neo-Tethyan oceanic plate (mid-ocean ridge basalt (MORB) + sediment + fluid), with some degree of subsequent peridotite interaction within the overlying mantle wedge. Combining regional data, we favour the interpretation that the Neo-Tethyan oceanic crust was subducted at a low angle beneath the Gangdese during the Early Cretaceous.

Ceropegia sunhangii P.R. Luo & T. Deng, a new species from Qiaojia, Yunnan, China, is described and illustrated herein. This species is similar to C. christenseniana Hand.-Mazz.and C. sinoerecta M. G. Gilbert & P. T. Li but can be distinguished easily by its stem, indumentum, leaf size, and floral features, especially the corolla shape and size, the corolla tube and corolla lobe characters.

Degradation state assessment of bearing is an important part of prognostic and health management (PHM) in rotating machinery. Generally, the energy distribution of frequency band is sensitive to degradation state for rolling bearing. Hence, a novel assessment method based on variational mode decomposition (VMD) and energy distribution is proposed in this work. Firstly, the VMD is used to decompose raw vibration signal into several components with different scales and frequency bands. These components is capable of reflecting the local characteristic of vibration signal. Then, the energy distribution of these components is utilized as feature vector. Finally, the different bearing states can be classified by the scatter plots of the first several principal components after principal component analysis (PCA). The analysis of an experimental dataset demonstrates the effectiveness of this methods. The comparative analysis shows the VMD is superior to traditional empirical mode decomposition (EMD) methods.

Based on newly collected material from the Lower Cretaceous (Hauterivian to Aptian) Yixian and Jiufotang formations of the Jehol Group, eight Cypridea species have been recognized in western Liaoning: C. ganzhaoensis, C. gujialingensis n. sp., C. jiufotangensis, C. vitimensis, C. beipiaoensis, C. subfracta, C. subelongata, and C. semiovata. Among them, one species from Kazuo area is new, Cypridea gujialingensis n. sp. Except for C. vitimensis, which has also been reported from Mongolia and western Siberia, the rest of the species are endemic to western Liaoning. On the basis of new material, we confirm sexual dimorphism in C. vitimensis and distinguish sexual and parthenogenetic populations. Paleobiologically, we infer a mixed reproduction mode for C. vitimensis and suggest that its sexual populations from western Liaoning could indicate stressful environmental conditions.

A phylogenetic analysis was carried out to clarify the systematic position of Gyrocheilos and Didymocarpus, particularly the species placed in Didymocarpus sect. Heteroboea by Wang et al. Based on sequencing the internal transcribed spacer and the chloroplast spacer trnL-F, parsimony and Bayesian inference analyses were carried out using separate nuclear and chloroplast datasets, as well as a combined dataset. Our results showed that the two sections of Didymocarpus in China and Gyrocheilos did not form separate monophyletic subclades, but turned up in three different places in the phylogenetic trees. In the frame of the present study, the pollen morphology of the species included in the analysis was studied. It proved inconsistent with the delimitation between Didymocarpus and Gyrocheilos. Furthermore, pollen and other morphological characters indicate that Gyrocheilos and some taxa of Didymocarpus should be placed within Didymocarpus.

This paper presents a novel method to controlling uncertain chaotic systems by means of sliding mode control based on fuzzy radial basis function neural network(FRBF). The proposed method combines the advantages of weights direct-determination, sliding mode control compensator and neural network. The neural network with five layer is constructed. For this neural network, the activation is sigmoid membership function, and the optimal weights received by weights direct-determination. The identification of chaotic system is first inferred by the modified FRBF in order to realize the nonlinear mapping between input and output, and its approximation ability to any chaotic system is perfective. Then the sliding mode compensation control is implemented by using the FRBF model. The performance of simulation results show the scheme is effective and feasible for uncertain chaotic system, and the robustness is provided on the parametric and extern disturbance.

In this paper, based on the definition of prime filters of fuzzy lattice, a new definition of L-fuzzy prime filters of L-fuzzy sub-lattice was given. With the tool of four kinds of level sets, several equivalent characterizations of L-fuzzy prime filters were given. Furthermore, we studied some of the properties of L-fuzzy prime filters. The results obtained on L-fuzzy sublattice will be of more general senses.