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The adoption of DNA-based assessments for biodiversity monitoring has been on the rise. However, the effectiveness of DNA-based taxonomic assignments heavily relies on the availability and reliability of DNA barcode libraries. There is growing demand for a comprehensive understanding of aquatic biodiversity and the critical role of Chironomidae, specifically Stenochironomus in freshwater ecosystems. Therefore, our objective is to develop a reference barcode library for Stenochironomus in China. From 2016 to 2021, we collected Stenochironomus specimens in diverse Chinese landscapes using malaise traps, light traps, and sweep nets. These specimens were carefully preserved for DNA extraction and barcode sequencing. Our analysis unveiled 36 unique operational taxonomic units from 180 COI barcode sequences through a Neighbor-Joining tree and Automatic Barcode Gap Discovery program, highlighting a significant diversity within the Stenochironomus species. The findings emphasize the constraints of conventional morphological identification methods, especially for species with ambiguous morphologies. It also underscores the effectiveness of DNA barcoding in revealing hidden species diversity, known as cryptic species. Consequently, this study advocates for an integrated taxonomic approach, combining morphological and molecular data, to refine species identification and conservation strategies.

C26H18BrN3O2, monoclinic, P21/n (no. 14), a = 9.5191(14) Å, b = 23.056(3) Å, c = 10.0556(15) Å, β = 95.470(3)°, V = 2196.9(6) Å3, Z = 4, Rgt(F) = 0.0640, wRref(F2) = 0.1645, T = 296(2) K.

C18H16Cl4N2O3V, orthorhombic, Pbca (no. 61), a = 7.8555(3) Å, b = 21.6645(7) Å, c = 23.7584(8) Å, V = 4043.3(2) Å3, Z = 8, Rgt(F) = 0.0296, wRref(F2) = 0.0799, T = 296(2) K.

(1) Background: Chironomids are biological indicators, playing an important role in monitoring and assessing the changes in water ecosystems. Mitochondrial genomes have been widely applied as a molecular marker to analyze the taxonomy and phylogeny of insects. However, knowledge of the mitogenomes of Chironomus species is scarce at present, which limits our understanding of the evolutionary relationships among Chironomus. (2) Methods: In our study, the mitogenomes and their basic structure of 12 Chironomus species and one Microchironomus species were newly sequenced. Combined with reported mitogenomes, a total of 15 mitogenomes of Chironomus were selected for a comparative mitogenomic analysis and phylogenetic reconstruction of Chironomus. (3) Results: Each mitogenome of the Chironomus species has the typical 37 genes and a control region. The basic structure of the whole mitogenomes of Chironomus species is relatively conservative, and the genetic arrangements stay the same as the ancestral mitogenome. (4) Conclusions: Our study enriches the library of mitogenomes of chironomids and provides a valuable resource for understanding the evolutionary history of Chironomus.

A full scale water-cooled Passive Residual Heat Removal System was designed and built for a 2 MW Molten Salt Reactor. In the process of heating the water tank, the heat transfer characteristics of the condenser in the system had an important impact on the temperature distribution and the development of thermal stratification in the water tank. Therefore, the heat transfer characteristics of the condenser at single-phase natural convection stage need to be experimentally researched and theoretically analyzed. Aiming at the condenser in the system, a series of experiments were carried out. Considering the influence of tube bundle effect on natural convection heat transfer, a set of theories using hydraulic diameter as characteristic length were put forward and applied to analyze the experimental results, which indicated the good agreement with the previous correlations consequently. This study can provide theoretical feasibility and experimental reference for the design of commercial molten salt reactor system in the future.

Since data update over time and space constantly, many rough set based incremental techniques have been proposed. Whereas there is less work on fuzzy rough set based feature selection (i.e., attribute reduction) from the dynamic data, especially the continuous dynamic data. In order to address this problem, an incremental attribute reduction algorithm based on fuzzy rough set is proposed for continuous data. First, some incremental mechanisms on fuzzy rough set are proposed, such as the incremental mechanisms of fuzzy positive region. Only some instances have insufficient identification capabilities on existing attribute reduction. That is, for the fuzzy positive region, there exists a key instance set. The incremental reduction algorithm updates the reduction results on the existing data by only considering the instances in the key instance set, but not the entire universe. Therefore, the incremental algorithm can quickly obtain a reduction update on dynamic data. Finally, some numerical experiments demonstrate that the incremental algorithm is effective and efficient compared to non-incremental attribute reduction algorithms.The incremental algorithm can save computing time greatly, especially on the datasets with high dimension.

Entrepreneurial burnout is a common practical problem faced by entrepreneurs under the pressure of multiple roles. Drawing on theory related to self-identity and conservation of resource, this study reveals the mechanism between role overload and entrepreneurial burnout, as well as the moderating effect of perceived social support. We used SEM structural equations to test the main effects, and Bootstrap repeated sampling was used to estimate the indirect effects and their sampling distribution. At the same time, multiple regression analysis was carried out using Process to test the regulatory effect.The results show that role overload is positively correlated with burnout, obsessive passion plays a mediating role, and perceived social support plays a moderating role.

C20H20Br2Cl2N2O3V, monoclinic, P21/c (no. 14), a = 11.9615(8) Å, b = 16.5865(7) Å, c = 12.9110(10) Å, β = 115.879(9)°, V = 2304.7(3) Å3, Z = 4, Rgt(F) = 0.0459, wRref(F2) = 0.1132, T = 153(2) K.

C21H16ClN3O2, monoclinic, C2/c (no. 15), a = 19.0523(19) Å, b = 9.3818(8) Å, c = 21.0602(17) Å, β = 107.303(10)°, V = 3594.0(6) Å3, Z = 8, Rgt(F) = 0.0644, wRref(F2) = 0.1655, T = 173(1) K.

C4H7N4O5V, monoclinic, P21/c (no. 14), a = 9.6179(8) Å, b = 8.3133(7)(11) Å, c = 10.8235(9) Å, β = 102.253(2)°, V = 845.69(12) Å3, Z = 8, Rgt(F) = 0.0242, wRref(F2) = 0.0718, T = 296(2) K.