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In this study, the morphology and morphogenesis of Bakuella granulifera Foissner, Agatha, and Berger, 2002, isolated from soil in the Chanba National Wetland Park, Xi'an, China, were studied based on in vivo observations and protargol staining. The Chinese population is distinctly smaller than the type population from Namibia. Details of the ontogenetic process are provided for the first time and are summarized as follows: (1) the parental adoral zone is partly retained; (2) the left of the endoral forms a rather wide anlage and the proximal adoral membranelles are renewed; (3) the parental midventral complex contributes to the formation of the FVT cirral anlagen; (4) the marginal rows anlagen and dorsal kineties anlagen develop intrakinetally; (5) no caudal cirri are produced; and (6) the macronuclear nodules fuse to a single mass. In combination with previous studies, these findings suggest that the genus Bakuella is ontogenetically diverse. [ABSTRACT FROM AUTHOR]

A subsynchronous oscillation (SSO) phenomenon in a wind farm integrated with a modular multilevel converter (MMC)‐based high‐voltage direct current (HVDC) transmission system has been recently observed in the real world. An attempt is made in this paper to contribute to the understanding of the root cause of the SSO in the MMC‐HVDC connected wind farms. For that, the small‐signal impedance model of the MMC is first developed based on the harmonic state‐space (HSS) modelling method. An inherent low‐frequency resonance peak in the MMC excluding any control influence is identified by its terminal impedance. Arguably, this could be the reason why the SSO occurs in the MMC‐HVDC connected wind farms. In addition to that, the influence factors, such as main circuit parameters, controller parameters, and power level, on the stability of the interconnected system are examined, which can provide guidelines for the system design in order to guarantee the stability of the interconnected system. Based on the mechanism analysis, a stabilization control for suppressing the SSO in the MMC‐HVDC based wind farms is also proposed. Finally, the theoretical analysis and stabilization control are validated by both time‐domain simulations and field measurements in a real MMC‐HVDC connected wind farm in China. [ABSTRACT FROM AUTHOR]

This work aims to review the implementation situation of experiential learning (EL) in China’s hospitality education and explore the perceptions of students on the effectiveness of the adopted EL methods. Observations and focus group discussions are conducted in three vocational colleges and three universities in China. The study reveals that EL activities are widely utilized in China’s hospitality education. Generally, students state that EL is more effective than traditional classroom learning. Nonetheless, they consider some EL activities as being ineffectively implemented. Several suggestions are given in this paper to provide support to hospitality educators for improving the utilization of EL methods and facilitate student learning. Furthermore, unique EL methods that are not documented in literature are adopted in China’s hospitality education. [ABSTRACT FROM PUBLISHER]

The morphology, morphogenesis, and molecular phylogeny of a new oxytrichid ciliate, Oxytricha multilineata n. sp. isolated from a tributary of the YuYao River, Ningbo, China, were investigated. Oxytricha multilineata n. sp. is characterized as follows: body size about 85–110 × 30–40 µm in vivo; 18 frontoventral-transverse cirri; paroral distinctly bipartite; seven dorsal kineties with cilia about 18 μm long; two macronuclear nodules and two micronuclei. The main events during morphogenesis follow a typical Oxytricha pattern with two exceptions: (1) only one anlage is formed initially within parental dorsal kineties 1–3, each of which then divides and is distributed into the two filial products, that is, the dorsal kineties anlagen are formed in primary mode; (2) dorsal kineties 3 and 4 are formed by incomplete fragmentation. Phylogenetic analyses based on SSU rDNA sequence data reveal that O. multilineata n. sp. clusters with Oxytricha lithofera, Heterourosomoida lanceolata and Quadristicha setigera, and species of the genus Oxytricha did not form a monophyletic group, however nodal support is not sufficiently high to recover a robust phylogeny of the Oxytrichidae. [ABSTRACT FROM AUTHOR]