Discovery of novel Ooceraea (Hymenoptera: Formicidae: Dorylinae) species with 8-segmented antennae from China

Here we describe an Ooceraea species with 8-segmented antennae for the first time. A revised key for all the known species of this genus based on the worker caste is provided

Mitochondrial genomes of two Sinochlora species (Orthoptera): novel genome rearrangements and recognition sequence of replication origin

BACKGROUND: Orthoptera, the largest polyneopteran insect order, contains 2 suborders and 235 subfamilies. Orthoptera mitochondrial genomes (mitogenomes) follow the ancestral insect gene order, with the exception of a trnD-trnK rearrangement in Acridomorphs and rare tRNA inversions. A question still remains regarding whether a long thymine-nucleotide stretch (T-stretch) involved in the recognition of the replication origin exists in the control region (CR) of Orthoptera mitochondrial DNA (mtDNA). Herein, we completed the sequencing of whole mitogenomes of two congeners (Sinochlora longifissa and S. retrolateralis), which possess overlapping distribution areas. Additionally, we performed comparative mitogenomic analysis to depict evolutionary trends of Orthoptera mitogenomes. RESULTS: Both Sinochlora mitogenomes possess 37 genes and one CR, a common gene orientation, normal structures of transfer RNA and ribosomal RNA genes, rather low A+T bias, and significant C skew in the majority strand (J-strand), resembling all the other sequenced ensiferans. Both mitogenomes are characterized by (1) a large size resulting from multiple copies of an approximately 175 bp GC-rich tandem repeat within CR; (2) a novel gene order (rrnS-trnI-trnM-nad2-CR-trnQ-trnW), compared to the ancestral order (rrnS-CR-trnI-trnQ-trnM-nad2-trnW); and (3) redundant trnS(UCN) pseudogenes located between trnS(UCN) and nad1. Multiple independent duplication events followed by random and/or non-random loss occurred during Sinochlora mtDNA evolution. The Orthoptera mtDNA recognition sequence of the replication origin may be one of two kinds: a long T-stretch situated in or adjacent to a possible stem-loop structure or a variant of a long T-stretch located within a potential stem-loop structure. CONCLUSIONS: The unique Sinochlora mitogenomes reveal that the mtDNA architecture within Orthoptera is more variable than previously thought, enriching our knowledge on mitogenomic genetic diversities. The novel genome rearrangements shed light on mtDNA evolutionary patterns. The two kinds of recognition sequences of replication origin suggest that the regulatory sequences involved in the replication initiation process of mtDNA have diverged through Orthoptera evolution

Simopone fisheri sp. n., a new species of Dorylinae ants (Hymenoptera, Formicidae) from China, with an illustrated key to the S. grandidieri-group species

Simopone fisheri sp. n., a new species of the subfamily Dorylinae, is described based on the worker caste. The new species is separated easily from the other named congeners by the longitudinally striate sculpture on the posterolateral portion of pronotum. An illustrated key is presented to species of the S. grandidieri group based on the worker caste

Collaborative Control Method for Offshore Wind Farms with Friendly Access to Hydrogen Energy Systems During Typhoons

[Introduction] With the steady progress of the carbon peaking and carbon neutrality goals, more and more distributed renewable energy is connected to the power grid. Among them, in economically developed coastal areas with heavy power load, vigorously developing offshore wind power has become a hot point of wide concern for scholars at home and abroad. However, the inherent intermittency of wind power generation, especially when the offshore wind farm is actively disconnected from the main grid during typhoons, can adversely affect the receiving-end grid. [Method] In order to realize the friendly access of offshore wind power during typhoon, considering the advantages of hydrogen energy storage such as high storage efficiency, low emission and wide application, this paper proposed a collaborative control method between offshore wind farm and hydrogen management system (HMS). On the one hand, during the period of typhoon approaching, this method could maximize the use of wind energy for power generation under normal operation. On the other hand, when the typhoon passed through and the offshore wind farm was gradually disconnected from the grid, the hydrogen energy system released electric energy to alleviate the active power drop of the wind farm and solve the problems such as the ramp rate in the operation of the traditional wind turbine generator systems, so as to reduce its adverse impact on the receiving-end grid and effectively smooth the volatility of the offshore wind power output. This paper firstly introduced the physical modeling method and control model of offshore wind farm and hydrogen energy system in detail, and explained the collaborative control strategy between them according to the typhoon period. [Result] Finally, simulation results show that the proposed method enables the offshore wind farms to be more flexible and friendly to meet the grid-connected operation during typhoons. In addition, the hydrogen energy storage system can maximize the use of wind energy for power generation under normal operation. [Conclusion] Control the hydrogen energy system to release electric energy during typhoons can solve the problems such as the ramp rate of the traditional wind turbine generator systems, so as to reduce its adverse impact on the receiving-end grid

Research on the Impact of Executive Shareholding on New Investment in Enterprises Based on Multivariable Linear Regression Model

Based on principal-agent theory and optimal contract theory, companies use the method of increasing executives' shareholding to stimulate collaborative innovation. However, from the aspect of agency costs between management and shareholders (i.e. the first type) and between major shareholders and minority shareholders (i.e. the second type), the interests of management, shareholders and creditors will be unbalanced with the change of the marginal utility of executive equity incentives.In order to establish the correlation between the proportion of shares held by executives and investments in corporate innovation, we have chosen a range of publicly listed companies within China's A-share market as the focus of our study. Employing a multi-variable linear regression model, we aim to analyze this relationship thoroughly.The following models were developed: (1) the impact model of executive shareholding on corporate innovation investment; (2) the impact model of executive shareholding on two types of agency costs; (3)The model is employed to examine the mediating influence of the two categories of agency costs. Following both correlation and regression analyses, the findings confirm a meaningful and positive correlation between executives' shareholding and the augmentation of corporate innovation investments. Additionally, the results indicate that executive shareholding contributes to the reduction of the first type of agency cost, thereby fostering corporate innovation investment. However, simultaneously, it leads to an escalation in the second type of agency cost, thus impeding corporate innovation investment.Comment: Accepted by the 7th APWeb-WAIM International Joint Conference on Web and Big Data. (APWeb 2023

Tooling design and microwave curing technologies for the manufacturing of fiber-reinforced polymer composites in aerospace applications

The increasing demand for high-performance and quality polymer composite materials has led to international research effort on pursuing advanced tooling design and new processing technologies to satisfy the highly specialized requirements of composite components used in the aerospace industry. This paper reports the problems in the fabrication of advanced composite materials identified through literature survey, and an investigation carried out by the authors about the composite manufacturing status in China’s aerospace industry. Current tooling design technologies use tooling materials which cannot match the thermal expansion coefficient of composite parts, and hardly consider the calibration of tooling surface. Current autoclave curing technologies cannot ensure high accuracy of large composite materials because of the wide range of temperature gradients and long curing cycles. It has been identified that microwave curing has the potential to solve those problems. The proposed technologies for the manufacturing of fiber-reinforced polymer composite materials include the design of tooling using anisotropy composite materials with characteristics for compensating part deformation during forming process, and vacuum-pressure microwave curing technology. Those technologies are mainly for ensuring the high accuracy of anisotropic composite parts in aerospace applications with large size (both in length and thickness) and complex shapes. Experiments have been carried out in this on-going research project and the results have been verified with engineering applications in one of the project collaborating companies

Review of the ant genus Anochetus Mayr, 1861 (Hymenoptera, Formicidae) from China, with revival of the valid status of Anochetus gracilis

Eight species of the ant genus Anochetus are recognized in China: A. graeffei Mayr, A. lanyuensis Leong et al., A. longus sp. n., A. madaraszi Mayr, A. mixtus Radchenko, A. medogensis sp. n., A. risii Forel, A. subcoecus Forel. A. taiwaniensis Terayama, 1989 is proposed as a junior synonym of A. risii Forel, 1900. Anochetus gracilis Karavaiev, 1925 is restored from synonymy of A. risii. A key based on the worker caste is provided for the Chinese species