Integrating DNA sequence features for more accurate prediction of replication origins in some double-stranded DNA viral genomes

Ph.DDOCTOR OF PHILOSOPH

Polysaccharides isolated from Morinda officinalis How roots inhibits cyclophosphamide-induced leukopenia in mice

Purpose: To investigate the optimum parameters for extracting polysaccharides from Morinda officinalis How (MOP), and explore their inhibitory effects on leukopenia in mice.Methods: Orthogonal design was performed to investigate the optimum parameters for extracting MOP. A leukopenia mouse model was established by injection of cyclophosphamide (CTX) for three days. Thereafter, MOP (100, 200 and 400 mg/kg) was administered orally for 10 days. Furthermore, blood cells (leukocytes, neutrophil, lymphocyte and mononuclear cell) were analyzed, while serum IL-3 and IL- 6 were determined by ELISA. The thymus and spleen of the mice were separated and weighed to determine viscera indices.Results: Orthogonal design showed that the influence order of the four factors was extraction times (C) > ratio of water to raw material (RWM, D) > extraction time (B) > extraction temperature (A). The optimum extraction parameters for MOP were: extraction temperature (80 °C), extraction duration (2 h), no. of extractions (3), and ratio of water to raw material (30 mL/g). Furthermore, the results indicate that MOP (100, 200 and 400 mg/kg) elevated the levels of leukocyte (p < 0.01), neutrophil (p < 0.01), lymphocyte (p < 0.01) and mononuclear cell (p < 0.01) in leukopenia mice. Besides, MOP (100, 200 and 400 mg/kg) also increased thymus (p < 0.01) and spleen (p < 0.05) indices and serum levels of IL-3 (p < 0.05) and IL-6 (p < 0.01).Conclusion: Orthogonal design is a good strategy for optimizing extraction parameters of MOP. Furthermore, MOP stimulated synthesis of leukocytes in CTX-induced leukopenia in mice. Thus, MOP is a potential adjunct for the treatment of tumors/cancers.Keywords: Morinda officinalis, Polyscacharide, Orthogonal design, Leukopenia, Thymus index, Spleen inde

Optimizing the Age of Information in RIS-aided SWIPT Networks

In this letter, a reconfigurable intelligent surface (RIS)-assisted simultaneous wireless information and power transfer (SWIPT) network is investigated. To quantify the freshness of the data packets at the information receiver, the age of information (AoI) is considered. To minimize the sum AoI of the information users while ensuring that the power transferred to energy harvesting users is greater than the demanded value, we formulate a scheduling scheme, and a joint transmit beamforming and phase shift optimization at the base station (BS) and RIS, respectively. The alternating optimization (AO) algorithm is proposed to handle the coupling between active beamforming and passive RIS phase shifts, and the successive convex approximation (SCA) algorithm is utilized to tackle the non-convexity of the formulated problems. The improvement in terms of AoI provided by the proposed algorithm and the trade-off between the age of information and energy harvesting is quantified by the numerical simulation results

Task-driven Semantic-aware Green Cooperative Transmission Strategy for Vehicular Networks

Considering the infrastructure deployment cost and energy consumption, it is unrealistic to provide seamless coverage of the vehicular network. The presence of uncovered areas tends to hinder the prevalence of the in-vehicle services with large data volume. To this end, we propose a predictive cooperative multi-relay transmission strategy (PreCMTS) for the intermittently connected vehicular networks, fulfilling the 6G vision of semantic and green communications. Specifically, we introduce a task-driven knowledge graph (KG)-assisted semantic communication system, and model the KG into a weighted directed graph from the viewpoint of transmission. Meanwhile, we identify three predictable parameters about the individual vehicles to perform the following anticipatory analysis. Firstly, to facilitate semantic extraction, we derive the closed-form expression of the achievable throughput within the delay requirement. Then, for the extracted semantic representation, we formulate the mutually coupled problems of semantic unit assignment and predictive relay selection as a combinatorial optimization problem, to jointly optimize the energy efficiency and semantic transmission reliability. To find a favorable solution within limited time, we proposed a low-complexity algorithm based on Markov approximation. The promising performance gains of the PreCMTS are demonstrated by the simulations with realistic vehicle traces generated by the SUMO traffic simulator.Comment: Accepted by IEEE Transactions on Communication

STAR-RIS-Assisted Privacy Protection in Semantic Communication System

Semantic communication (SemCom) has emerged as a promising architecture in the realm of intelligent communication paradigms. SemCom involves extracting and compressing the core information at the transmitter while enabling the receiver to interpret it based on established knowledge bases (KBs). This approach enhances communication efficiency greatly. However, the open nature of wireless transmission and the presence of homogeneous KBs among subscribers of identical data type pose a risk of privacy leakage in SemCom. To address this challenge, we propose to leverage the simultaneous transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) to achieve privacy protection in a SemCom system. In this system, the STAR-RIS is utilized to enhance the signal transmission of the SemCom between a base station and a destination user, as well as to covert the signal to interference specifically for the eavesdropper (Eve). Simulation results demonstrate that our generated task-level disturbance outperforms other benchmarks in protecting SemCom privacy, as evidenced by the significantly lower task success rate achieved by Eve

Psychological mechanisms of English academic stress and academic burnout: the mediating role of rumination and moderating effect of neuroticism

IntroductionAcademic stress is a significant and prevalent phenomenon among college students. According to the Demands-Resources Model, when individuals are unable to cope with stress that exceeds their capacity, burnout may occur. Although English courses hold a significant position in university education, there has been limited research on the mechanisms linking English academic stress to English academic burnout.MethodsThis study recruited 1,130 undergraduate students taking English courses. Participants completed online questionnaires assessing English academic stress, rumination, English academic burnout, and neuroticism traits. A moderated mediation model was constructed to examine the relationship among these variables.ResultsThe results indicate that (1) Rumination serves as a mediator in the relationship between English academic stress and burnout; (2) neuroticism significantly moderates the pathway between English academic stress and rumination. Specifically, students with high neuroticism tendencies are more prone to developing rumination when faced with high levels of English academic stress.ConclusionThese findings offer valuable insights into the psychological mechanisms underlying the association between English learning stress and academic burnout. They emphasize the importance of addressing rumination as a mediator and considering individuals’ levels of neuroticism in interventions aimed at preventing and alleviating academic burnout among university students

Elucidating a fresh perspective on the interplay between exosomes and rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by chronic synovitis and the destruction of bones and joints. Exosomes are nanoscale lipid membrane vesicles originating from multivesicular bodies and are used as a vital means of intercellular communication. Both exosomes and the microbial community are essential in RA pathogenesis. Multiple types of exosomes from different origins have been demonstrated to have effects on various immune cells through distinct mechanisms in RA, which depend on the specific cargo carried by the exosomes. Tens of thousands of microorganisms exist in the human intestinal system. Microorganisms exert various physiological and pathological effects on the host directly or through their metabolites. Gut microbe-derived exosomes are being studied in the field of liver disease; however, information on their role in the context of RA is still limited. Gut microbe-derived exosomes may enhance autoimmunity by altering intestinal permeability and transporting cargo to the extraintestinal system. Therefore, we performed a comprehensive literature review on the latest progress on exosomes in RA and provided an outlook on the potential role of microbe-derived exosomes as emerging players in clinical and translational research on RA. This review aimed to provide a theoretical basis for developing new clinical targets for RA therapy

miR‐155 promotes macrophage pyroptosis induced by Porphyromonas gingivalis through regulating the NLRP3 inflammasome

ObjectiveThe aim of this study is to detect pyroptosis in macrophages stimulated with Porphyromonas gingivalis and elucidate the mechanism by which P. gingivalis induces pyroptosis in macrophages.MethodsThe immortalized human monocyte cell line U937 was stimulated with P. gingivalis W83. Flow cytometry was carried out to detect pyroptosis in macrophages. The expression of miR‐155 was detected by real‐time PCR and inhibited using RNAi. Suppressor of cytokine signaling (SOCS) 1, cleaved GSDMD, caspase (CAS)‐1, caspase‐11, apoptosis‐associated speck‐like protein (ASC), and NOD‐like receptor protein 3 (NLRP3) were detected by Western blotting, and IL‐1β and IL‐18 were detected by ELISA.ResultsThe rate of pyroptosis in macrophages and the expression of miR‐155 increased upon stimulation with P. gingivalis and pyroptosis rate decreased when miR‐155 was silenced. GSDMD‐NT, CAS‐11, CAS‐1, ASC, NLRP3, IL‐1β, and IL‐18 levels increased, but SOCS1 decreased in U937 cells after stimulated with P. gingivalis. These changes were weakened in P. gingivalis‐stimulated U937 macrophages transfected with lentiviruses carrying miR‐155 shRNA compared to those transfected with non‐targeting control sequence. However, there was no significant difference in ASC expression between P. gingivalis‐stimulated shCont and shMiR‐155 cells.ConclusionsPorphyromonas gingivalis promotes pyroptosis in macrophages during early infection. miR‐155 is involved in this process through regulating the NLRP3 inflammasome.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152887/1/odi13198_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152887/2/odi13198.pd

The effects of ethylene on the HCl-extractability of trace elements during soybean seed germination

Background: Ethylene is capable of promoting seed germination in some plant species. Mobilization of metals such as Fe, Cu, Mn, and Zn in mature seeds takes place when seeds are germinating. However, whether ethylene is involved in the regulation of soybean seed germination and metal element mobilization during early seed germination stage remains unknown. In the present study, seeds were treated with ethylene synthesis inhibitor aminoethoxyvinylglycine (AVG) and ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), and double distilled H2O (ddH20) treatment was used as control. Ethylene emission, ACC synthase (ACS) expression, ACS enzyme activity and Ca, Zn, Mn, Cu and Fe content in hypocotyls were qualified to analyze the relationship between ethylene and mobilization of these elements. Results: The results showed that ACS expression, ACS enzyme activity and ethylene emission peaked at 1 and 7 d after sowing. AVG inhibited ethylene production, promoted the hypocotyls length, ACS expression and its activity, concentrations of total and HCl-extractable Zn, and HCl-extractable Fe in hypocotyls, while ACC caused opposite effects. AVG and ACC treatment had no significantly effects on total and HCl-extractable Ca, Cu and HCl-extractable Mn. Total Mn concentration was promoted by AVG at 1, 3, and 5 d significantly, while ACC treatment tended to have no significantly effects on Mn concentration. Conclusion: These findings suggested that ethylene is at least partly involved in the regulation of soybean seed germination. Remobilization of Zn and Fe may be negatively regulated by ethylene