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Currently, the design of coal mine roadway support schemes is still mainly based on manual design, engineering analogy, and FLAC model simulation, which has problems such as strong subjectivity, low universality, and insufficient utilization of coal mine support big data. The design method based on expert systems has cumbersome rule setting procedures, large engineering quantities, and low intelligence. Case based reasoning (CBR) and deep learning techniques are introduced into the field of roadway support scheme design. Based on text big data such as coal mine support regulations, support standards, and coal mine roadway geological reports, an intelligent design method for coal mine roadway support scheme is proposed. The method obtains 346 sets of roadway support data from different coal mines, extracts structured data and divides it into input and output parameters, and optimizes the input and output parameters through constant attribute variable filtering and high correlation filtering methods. The method establishes a CBR model and imports the extracted structured data into the CBR model to form a case library of support scheme comparison and selection. The method calculates the similarity between the new roadway support scheme and the historical scheme, and outputs the three historical schemes with the highest similarity for comparison, achieving similar case comparison. BP neural network and long short term memory (LSTM) network are respectively used to establish automatic generation models for coal mine roadway support schemes. By comparing the prediction indicators, it is determined to use the combination of LSTM model and CBR model to establish an intelligent design system for coal mine roadway support scheme. The system is used for the design of auxiliary transportation roadway support scheme in the F6226 working face of Buliangou Coal Mine excavation. Through experiments, it is verified that the deformation of the two sides of the roadway and the maximum displacement of the roof under the system generated scheme are smaller than those under the manual design scheme. The integrity of the roadway roof and two sides is good, the bearing capacity of the surrounding rock is enhanced, and the support effect is significant.

With the development of blockchain technology, due to the different system architecture and application scenarios of blockchain platforms, it is difficult to realize the interconnection and intercommunication of data and assets on different blockchains, which affects the promotion and application of blockchain. The cross-chain tech-nology of blockchain is an important technical solution to realize the interconnection of blockchain and improve the interoperability and extensibility of blockchain. The blockchain cross-chain protocol is the specific design specifi-cations to realize the cross-chain interoperability between different blockchains through cross-chain technology, so it is of great significance to the realization of blockchain interoperability and the construction of blockchain cross-chain application. This paper systematically arranges and analyzes the latest researches on the integration and implemen-tation of blockchain cross-chain protocols, and places them in four hierarchies: Firstly, the current research status of blockchain cross-chain interoperability is explained from three aspects, Internet of blockchains, cross-chain techno-logy and blockchain interoperability. Secondly, the cross-chain protocols are divided into cross-chain communi-cation agreements, cross-chain asset transaction agreements and cross-chain smart contract call agreements, and the latest research is analyzed. Thirdly, the key design principles of cross-chain protocols are summarized, and the solutions for the problems of security, privacy and scalability of cross-chain protocol are provided. Finally, com-bined with the actual needs of blockchain cross-chain applications, the future research direction of blockchain cross-chain protocol is given.

Abstract Topologically associating domains (TADs) are the organizational units of chromosome structures. TADs can contain TADs, thus forming a hierarchy. TAD hierarchies can be inferred from Hi-C data through coding trees. However, the current method for computing coding trees is not optimal. In this paper, we propose optimal algorithms for this computation. In comparison with seven state-of-art methods using two public datasets, from GM12878 and IMR90 cells, SuperTAD shows a significant enrichment of structural proteins around detected boundaries and histone modifications within TADs and displays a high consistency between various resolutions of identical Hi-C matrices.

Blockchain provides a new technology for building transmission and trust mechanism of social ralue. The rapid development of blockchain has promoted the deep integration of smart contract with artificial Intelligence, big data and internet of things, so its security has attracted attention. In recent years, researches on security of blockchain and smart contract have made great progress. Thus, based on smart contract on the blockchain, the related works on security of operating mechanism, on-chain smart contract security and off-chain security were classified, analyzed, compared, summarized and discussed. The hot issues of smart contract security in the future were forecasted.

Objectives This study is focused on whether CFD can be used to analyze the temperature distribution in the core storage of ocean exploration vessels.Methods In the core storage of ocean exploration vessels, high-temperature storage is 4℃, low-temperature storage is -20℃ and temperature control accuracy is ±1℃. The standard k-ε turbulence model is used in this paper for CFD simulation. In the case of an empty storage ceiling, a transverse layout, a longitudinal layout and an oblique layout are separately adopted on the deployment scheme of the air cooler for high and low temperature storage. The temperature distributions of the different layout schemes are simulated to determine the optimal layout of the air cooler. Then the simulation results are compared with the experimental results.Results The result shows that when the air cooler adopts the transverse ceiling layout, the temperature deviation degree is small, and the temperature is mostly distributed in qualified areas, therefore this layout is selected. In the case of the transverse layout ceiling arrangement, the error between the simulation results and experiment results, is below 10%. This shows that the simulation results are reasonable.Conclusions CFD can accurately simulate temperature distribution in core storage, providing a strong scientific basis for the future design of core storage air coolers.

Human fetal scleral fibroblasts (HFSFs) are components of the sclera and play important roles in its structure and function. In myopia, scleral remodeling reduces collagen fibers and the sclera begins to thin. NANOG is a key transcription factor essential for pluripotent and self-renewing phenotypes of undifferentiated embryonic stem cells. To determine whether NANOG improves human fetal scleral fibroblast quality and the underlying mechanisms in these cells, we established stable NANOG-overexpressing HFSFs. We studied type I collagen (COL1A 1) and Rho-associated coiled-coil protein kinase 1 (ROCK1) expression in transfected cells. We also investigated POU5F1, SOX2, KLF4, MYC and SALL4 expression in NANOG stably-overexpressed fibroblasts. Our data show that NANOG expression increased proliferation rates in fibroblasts. When compared to controls, expression of COL1A 1 in transfected fibroblasts was increased and the expression of ROCK1 was decreased. Similarly, the expression of POU5F1, SOX2 and KLF4 was downregulated, the expression of MYC was upregulated and there was no significant change in the expression of SALL4 in transfected fibroblasts. Our results suggest that in fibroblasts, NANOG regulates ROCK1 expression and improves COL1A 1 expression to delay scleral remodeling.

Due to the influence of the process, actual frequency of clock generator module always has some deviations from target, it is necessary to trim the clock module whose frequency is not as it was expected. Compared with traversing method, dichotomy has higher convergence rate. Auto trim circuit was designed based on dichotomy, and measurement error caused by synchronous of referenced pulse was analyzed. Auto trim circuit counted output of clock generator module during high level of referenced slow pulse which was generated by automatic test equipment, and trim value was changed using dichotomy, achieving the purpose of saving measure time.

The European corn borer (Ostrinia nubilalis) is one of the most important insect pests of maize, and has a significant impact on the production of this crop. In this work, we examined the effects of different insecticides on the antioxidative defense system of O. nubilalis larvae. The experimental setup consisted of a completely randomized block design with 4 replicates. Four experimental groups were formed as follows: control (C), indoxacarb (250 mL ha-1), chlorantraniliprole (100 mL ha-1) and the chlorantraniliprole+lambda cyhalothrin (200 mL ha-1) group. Larvae from maize stems were collected 20 days after insecticide application and the whole larvae were homogenized. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST), and the total amount of free SH groups were assessed. Comparison of the experimental groups showed that indoxacarb significantly affected the activities of GST, GPx and the total amount of free SH groups, while chlorantraniliprole significantly affected the activities of SOD, CAT, GST and the total amount of free SH groups, while chlorantraniliprole+lambda cyhalothrin significantly affected the activities of CAT, GST and the total amount of free SH groups. The results show that exposure to insecticides considerably affects the antioxidative defense components of the European corn borer larvae, especially chlorantraniliprole (T2). [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 173027]

To explore the effects of Shanxian Granules (SXG) on diethylnitrosamine (DEN) -induced precancerous lesions in rats and its possible molecular mechanism. A total of 50 male SD rats (190±10 g) were randomly divided into five groups. control group, DEN group, SXG low dose group, SXG medium dose group and SXG high dose group. The control group received saline injection. The precancerous liver cirrhosis group received 50mg/kg DEN via intraperitoneal injection twice a week for 16 weeks. The indexes of liver function (ALT, AST and GGT) were measured by blood sampling. HE staining was used to observe pathological changes of liver tissues. The levels of IL-6 and TNFα were measured by ELISA kits. Compared with the model group, the high (P