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Background: Pseudogenes are sequences that have lost the ability to transcribe RNA molecules or encode truncated but possibly functional proteins. While they were once considered to be meaningless remnants of evolution, recent researches have shown that pseudogenes play important roles in various biological processes. However, the studies of pseudogenes in the silkworm, an important model organism, are limited and have focused on single or only a few specific genes. Objective: To fill these gaps, we present a systematic genome-wide studies of pseudogenes in the silkworm. Methods: We identified the pseudogenes in the silkworm using the silkworm genome assemblies, transcriptome, protein sequences from silkworm and its related species. Then we used transcriptome datasets from 832 RNA-seq analyses to construct spatio-temporal expression profiles for these pseudogenes. Additionally, we identified tissue-specifically expressed and differentially expressed pseudogenes to further understand their characteristics. Finally, the functional roles of pseudogenes as lncRNAs were systematically analyzed. Results: We identified a total of 4410 pseudogenes, which were grouped into 4 groups, including duplications (DUPs), unitary pseudogenes (Unitary), processed pseudogenes (retropseudogenes, RETs), and fragments (FRAGs). The most of pseudogenes in the domestic silkworm were generated before the divergence of wild and domestic silkworm, however, the domestication may also involve in the accumulation of pseudogenes. These pseudogenes were clearly divided into 2 cluster, a highly expressed and a lowly expressed, and the posterior silk gland was the tissue with the most tissue-specific pseudogenes (199), implying these pseudogenes may be involved in the development and function of silkgland. We identified 3299 lncRNAs in these pseudogenes, and the target genes of these lncRNAs in silkworm pseudogenes were enriched in the egg formation and olfactory function. Conclusions: This study replenishes the genome annotations for silkworm, provide valuable insights into the biological roles of pseudogenes. It will also contribute to our understanding of the complex gene regulatory networks in the silkworm and will potentially have implications for other organisms as well. [ABSTRACT FROM AUTHOR]

The ability of engineering graduate students to use their knowledge and independently engage in scientific research is one of the important indicators to measure the quality of postgraduate training. This paper takes the comprehensive improvement of graduate students’ ability to engage in scientific research independently as the starting point, and improves the teaching quality of basic courses of graduate majors in an all-round way by constructing teaching methods of basic knowledge intensive teaching, knowledge application and case process teaching, so that students can deeply grasp the course knowledge system and flexibly apply the knowledge learned in the course learning process. Finally, it lays a good foundation for students to engage in scientific research independently.

In this paper, the progressive damage model of T800 carbon fiber composite double-bolt joint based on Hashin criterion was established based on the finite element analysis. By changing the bolt diameter, the numerical simulation of the strength change of the joint was carried out. The damage evolution process was studied and the corresponding verification test research was carried out. Finally, the damage and failure process of the T800 carbon fiber composite double-bolt joint is given, and the strength optimization design scheme is proposed.

Based on the HyperWorks software, this paper takes the layup sequence of carbon fiber composite laminates as the design variables, the main strain of the laminates and the continuous angle layup not exceeding four layers as constraints, and the maximum bearing capacity as the design goal. The optimized design of the laminate and the corresponding experimental verification were carried out. The experimental results are in good agreement with the simulation analysis results, indicating that the optimization design method proposed in this paper is reasonable.

Molecularly imprinted polymers (MIPs) were synthesized via the precipitation polymerization technology for the specific adsorption of morphine. A number of polymers (methacrylic acid, trifluoromethyl acrylic acid, and acrylamide) were studied, respectively, as the precursor monomers under various synthetic conditions (the imprinting (IP) ratio, cross‐linking (CL) ratio, solvent ratio, reaction temperature, etc.). The MIP with optimal performance was derived using methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinker, and azobisisobutyronitrile (AIBN) as the initiator, with an IP ratio of 1:3 and a CL ratio of 5:1. This MIP presented a maximum morphine adsorption capacity of 38.24 mg/g (one of the highest capacities ever reported in the literature) at a bulk morphine concentration of ~230 ppm in acetonitrile solution. The adsorption capacity, selectivity, reusability, as well as the chemical and mechanical stabilities of the MIP were confirmed by the adsorption experiments, instrumental characterization, thermodynamic analysis, as well as the proposed mechanisms. [ABSTRACT FROM AUTHOR]

In order to study compatibility of tank materials and liquid propellants, electrochemical tests and full immersion tests were utilized to explore the corrosion mechanism of 2195-T8 aluminum lithium alloys in HNO3, and the corrosion process was simulated based on cellular automata method. The results show that the alloy has the fastest corrosion rate in HNOj whose mass fraction is as 30%; pitting corrosion occurs in the early stage of corrosion, and then gradually forms exfoliation corrosion. The fitted equivalent circuit reflects the dynamic processes of the alloys in HNO3 and explains the phenomenon of inductive reactance in the fourth quadrant of electrochemical impedance spectroscopy. Cellular automata model adopted Logistic distribution probability as critical condition of corrosion probability, and the simulation results correspond to that of the tests. [ABSTRACT FROM AUTHOR]

The potential of flow cytometry for the study of changes in prodigiosin on the cell surface of Serratia marcescens is of academic and practical interest. This is because S. marcescens can produce prodigiosin, a secondary metabolite, with potential use as a cancer‐cell inhibitor. In this study, three groups of bacterial cultures with different carbon sources were compared, and the effect of the addition of cAMP to the sucrose‐based culture was studied. Both cellular morphology and DNA content were detected by flow cytometry, rendering a broad description of the bacterial behavior. It is the first use of flow cytometry to investigate the dynamics of prodigiosin on the surface of S. marcescens during growth in different media. The fluorescence intensity is related to the DNA content, the forward‐scattered light is related to cell volume, and the side‐scattered light is related to the surface morphology, especially the surface prodigiosin. These may contribute to the potential development of a bacterial metabolic monitoring strategy using both DNA content analysis and bacterial morphology based on flow cytometry technique. [ABSTRACT FROM AUTHOR]

The high strength aluminum alloy double cantilever beam (DCB) specimens were corroded under the conditions of different liquid propellant environment. After the stress corrosion exposure, the scanning electron microscopy and energy-dispersal analyses on corrosion damage were carried out. The corrosion damage sensitivity and the stress corrosion character of the LD10 high strength aluminum alloy in N2O4, UDMH and 3.5% NaCl corrosion solution were analyzed.