Four different environmental DNA libraries were prepared from microbial consortium collected from forest soil, dung of elephant, cow rumen and rotted tree. Seven independent clones specifying cellulase activities (five endo-beta-1,4-glucanases and two beta-glucosidases) were isolated and identified. Sequence analysis of the retrieved genes revealed that the encoded products of these cellulase genes shared less than 50% identities and 70% similarities to cellulases in the databases. Domain analysis predicted that four endo-beta-1,4-glucanases conform to glycolsyl hydrolase family 5 (GHF 5) and one endo-beta-1,4-glucanase to glycolsyl hydrolase family 9 (GHF 9), while both beta-glucosidases belong to glycolsyl hydrolase family 3 (GHF 3). Further sequence analysis indicated that although a solid affiliation could be made for the two endo-beta-1,4-glucanases to the typical ruminal microbe Prevotella ruminicola, the rest formed deep-branched lineages with no close relatives. The revelation of the phylogenetic novelty provided a snapshot on the great diversity of cellulases in these natural environments.

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In this paper, a minimum-time motion online planning (MTMOLP) method is proposed for underactuated overhead crane systems within both safety and physical constraints. First, the motion process is divided into seven stages by analyzing the coupling between trolley movement and payload swing, and a minimum-time motion planning problem and the expression of its solution are presented. Second, a state prediction method based on the payload swing energy is given to compute the solution of the motion planning problem in real time. Finally, several simulations and experiments are conducted to verify the feasibility and effectiveness of the proposed method. The results show that the MTMOLP method can obtain the solution of the minimum-time motion planning problem with spending very little time on the computing process. Therefore, it can be applied to the online motion planning of the overhead cranes. Furthermore, the motion process division by the coupling analysis can also provide a reference for the underactuated control of overhead crane systems. INDEX TERMS Motion online planning, minimum-time, underactuated systems, overhead cranes.

Summary This paper addresses stability and l2‐gain for discrete‐time switched systems with unstable modes based on slow/fast mode‐dependent average dwell time (MDADT) switching strategies. Firstly, by employing a class of multiple discontinuous Lyapunov functions (MDLFs) and developing a kind of alternative switching signals, the sufficient conditions on stability are established for the system without external disturbances under a slow/fast MDADT switching scheme with a tighter bounds on the dwell time. Furthermore, by defining indicator functions and exploring the features of slow/fast MDADT switching, the weighted l2‐gain conditions are achieved for the system with external disturbances. Particularly, the criteria of stability and l2‐gain are also established for the corresponding discrete‐time switched linear systems with unstable modes via the MDLFs method and the slow/fast MDADT switching strategy. Finally, two numerical examples are presented to illustrate the advantages of the proposed methods.

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