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CD8+ T cells are the primary mediators of antigen-specific immune responses, with their functional states finely regulated by molecular mechanisms, playing a crucial role in tumor immunity. In recent years, CD8+ T-cell-based cellular therapies (e.g., TCR-T and CAR-T cell therapy) and immune checkpoint therapies that block PD-1 signaling pathway have achieved unprecedented success in clinical cancer treatments. However, the therapeutic effects of these immunotherapies are still limited, mainly due to immune resistance, with a significant factor being the functional exhaustion of tumor antigen-specific CD8+ T cells. Consequently, a major focus and challenge in immunotherapy research is to understand the regulatory mechanisms behind this functional exhaustion and to develop intervention strategies and targets to enhance CD8+ T cell effector functions. This article reviews the research progress in antitumor immune responses of CD8+ T cells from three perspectives: The heterogeneity of exhausted CD8+ T cells, their response to PD-1 immune checkpoint blockade (ICB), and their epigenetic characteristics.

Caries is a chronic infectious disease that occurs in the hard tissues of teeth. The interaction of oral microorganisms, host, food and time leads to the occurrence and progression of caries. Free sugar is an important food factor in the occurrence of dental caries. This paper reviews the research progress on the relationship between free sugar and caries in recent years, providing a reference for further clarifying the mechanism of the occurrence and progression of caries caused by free sugar and exploring the methods of caries prevention. The cariogenic mechanism of free sugar is multifaceted. Free sugar can not only be used by oral microorganisms in dental plaque biofilms to produce acid and synthesize intracellular and extracellular polysaccharides but also cause an imbalance in oral microecology and enhance gene expression related to the cariogenic toxicity of oral microorganisms. Based on the correlation between free sugar and caries, it is important to limit the intake amount and frequency of free sugar to prevent caries. This can be achieved mainly by formulating public health policies for reducing sugar, creating a low-sugar family environment with good eating habits, using sugar substitutes and using fluoride. There are few studies on the relationship between free sugar and oral microecology. More research is needed to better understand the effect of free sugar on oral microecology and its mechanism and to validate the caries-preventing effect of various sugar reduction measures. We believe such studies would open up new avenues for the effective prevention of caries.

In order to meet the motion requirements of the elbow joint of the rehabilitation robot, a double-node symmetrical spiral corrugated elastic element is applied to the series elastic actuator (SEA), and the energy storage ratio is used as the optimization standard. Under the premise of the same quality,the maximum energy storage ratio can be achieved, which can better absorb the vibration of the mechanical arm and ensure the safety of the patient. Firstly, the three-dimensional modeling of the SEA is carried out. Then the torque spring is simulated and analyzed by using the finite element software, and the safety factor of the elastic unit is 2.37. Finally, the real object is processed. The experiment shows that the energy storage ratio can reach 9.63 J/kg, the measured stiffness kr is 264.04 N∙m/rad, the error of the simulated stiffness is 6.86%, and the torsion angle and torque of the elastic unit are linear and can be used for the flexible connection of the robotic arm, which lays the foundation for the further optimization of the robot, and also provides a technical verification method for solving such problems.

Objective： This study aimed to solve the problems of yellowing, discoloration and quality preservation of broccoli after harvesting. Methods： Broccoli was fumigated with chlorine dioxide gas at different mass concentrations (0,0.2, 0.5, 1.0, 1.5, 2.0 mg/L) at 23 ℃, and the sensory, color, yelination grade, physiological and biochemical indexes and related browning enzyme activities of broccoli were determined after 0,2,4,6,8 days of storage. Results： Compared with the control group, different mass concentrations of ClO2 could inhibit the mass loss rate, yellowing browning and spoilage of flower buds of broccoli. ClO2 at 0.5 and 1.0 mg/L had a more significant effect on the maintenance of chlorophyll content, color difference a* and b*, and the inhibition of PPO and POD enzyme activities in broccoli. Among them, 0.5 mg/L ClO2 had the best effect on maintaining the color difference value of broccoli flower buds, and the yelination grade was still grade Ⅱ on the 8th day of storage. Simultaneously, it effectively maintained the vitamin C content and delayed the yelination and Browning of flower buds. Conclusion： It is necessary to control the concentration of ClO2 gas in the fumigation treatment of broccoli to obtain the best effect of maintaining the fresh green of broccoli bulbs and extending the shelf life.

The total production of global plastics is up to 400 million tons per year. Nearly 80% of the used plastics are directly landfilled or dumped in the environment, leading to the generation and release of microplastics, which poses a great threat to both environment and human health. How to recycle plastic waste efficiently and environmentally has become a common concern worldwide. Among the plastic waste recycling methods, chemical recycling such as pyrolysis can realize the transformation from polymer to high-value products. This paper summarizes the research and industrialization progress of four different plastic waste pyrolysis technologies, namely fast pyrolysis, catalytic pyrolysis, oxidative pyrolysis and hydro-pyrolysis. The challenges faced by the pyrolysis of plastic waste is discussed and the future development direction of various pyrolysis technologies is also outlooked. It is expected that some more efficient, environmentally friendly, and economical technologies of plastic waste pyrolysis can be explored in the future, to meet the growing demand for environmental protection and sustainable development.

Porphyromonas gingivalis (P. gingivalis) is closely related to the occurrence and development of periodontitis. It is considered to be one of the important pathogens leading to alveolar bone resorption. At present, research on P. gingivalis mostly adopts standard laboratory strains whose genetic characteristics have been confirmed, are guaranteed and are traceable, such as ATCC 33277. The virulence phenotypes (endotoxin, firmbria, etc.) of clinically extracted isolates are quite different from those of standard strains, and the pathogenic effects and ability of the host are also widely different. In addition, P. gingivalis is considered to have a significant correlation with a variety of systemic diseases, and the virulence characteristics and pathogenic ability of different strains will have different effects on systemic diseases. However, at present, there is a lack of research on clinical strains and standard strains, and there is a lack of systematic comparison between the two sources of bacteria. In this paper, the differences in the virulence phenotypes and pathogenic effects between clinical isolates and standard strains of P. gingivalis in the last 5-10 years are reviewed. The aim is to elucidate the important virulence gene loci in the P. gingivalis gene sequence, which will play an important role in improving therapeutic methods and the development of related drugs.

In this paper, the chain structure of magnetorheological fluid (MRF) magnetic particles was studied and analyzed, the mechanical model of MRF with different diameter ferromagnetic particles was established, silicone oil-based MRF with different particle volume fractions was prepared, the shear properties of the MRF were tested, and the theoretical and experimental data were compared. The experimental results show that the shear stress is stable with the increase of shear strain rate under the action of the magnetic field, and it has a shear thinning effect. The shear stress increases linearly with the increase of particle volume fraction. The shear stress increases with the increase of magnetic induction intensity. After data analysis and in the case of control variables, the average error of improved theoretical data and experimental data is lower than that of previous theoretical data and experimental data, which verifies that the improved theory (mechanical model) has a certain accuracy.

【Background and objective】 The response of the reference evapotranspiration (ET0) to climate change and its underlying determinants has attracted increased interest over the past decade, but there is a lack of knowledge about how ET0 in Tibet has changed. This paper is to plug this gap. 【Method】 ET0 in three irrigation districts, Manla, Moda and Jiangbei, was calculated using the Penman-Monteith equation recommended by FAO based on long-term meteorological data measured from each district. Conversion from quantitative ET0 to qualitative description of ET0 was calculated using the cloud model, from which the homogeneity and stability indexes were used to analyze the temporal variation of ET0 as well as its contributing factors. We also analyzed the meteorological factors that affect ET0 most in the three irrigation districts using the path coefficient analysis. 【Result】 Annual ET0 in Jiangbei and Moda had been in decrease from 1991 to 2016 at an average rate of 27.97 mm/(10a) and 6.41 mm/(10a) respectively, but increased in Moda at an average rate of 9.99 mm/(10a) though not at significant level. The annual ET0 was most temporally uniform and stable in Jiangbei, and least in Moda. Seasonally, the magnitude of ET0 was ranked in the order of summer > spring > autumn > winter in all three irrigation districts. ET0 was most temporal uniform and stable in winter and spring, and least in summer and autumn. Monthly, ET0 peaked in summer and it was most temporally stable in January, and least in May. Path coefficient analysis showed that ET0 was affected by several meteorological factors, and their significance varied between districts. Average relative humidity directly affected ET0 in Manla and Moda most, while average wind speed directly affected ET0 in Jiangbei more than other factors. Daily sunshine had an indirect effect on ET0 in Moda. 【Conclusion】 ET0 in Jiangbei had been in decline since 1991 at an average rate 27.97 mm/(10a) despite being most temporally stable and uniform. Wind speed and average relative humidity were the main factors affecting ET0 in all three irrigation districts.

The Streptococcus mutans (S. mutans) phage, as one of the principal pathogenic bacteria of dental caries, is a main cause of the formation and development of dental caries due to its overproliferation in dental plaque biofilms. Bacterial viruses, also known as bacteriophages, have the capability of specifically infecting bacteria and effectively degrading bacterial biofilms. S. mutans phages, therefore, may prevent and control caries. Therapy based on phages has been applied in many fields, but the application of S. mutans phages in caries remains exploratory. This article will review the research progress of S. mutans phages in clinical caries prevention, aiming to provide a new idea for the clinical prevention of caries. The results of the literature review show that the living bacteriophage system has the advantages of high specificity, high affinity and good safety. However, due to its unstable structure, it can be processed into a more stable formulation by freeze-drying, spray drying, adding stability enhancers, or incorporating bacteriophages into ointments, biodegradable polymer matrices or particles to a certain extent to improve stability. The lysozyme produced by phages can digest the bacterial cell wall and release the assembled phage particles, which effectively cleave biofilms. In addition, the antigen binding fragment library for cariogenic pathogens was screened by phage display technology, and the purpose of caries prevention and treatment was achieved by passive immunization of antigen binding fragments. However, the host range of bacteriophages is narrow, so this kind of problem can be overcome by phage combined with traditional therapy or other drug use or cocktail therapy with multiple phages in clinical caries prevention and control.

Objective To investigate the effect of VRK1 expression downregulated by siRNA on BANF1 expression and the proliferation and migration abilities of esophageal squamous cell carcinoma (ESCC) cells. Methods VRK1 siRNA was transfected into EC109 and EC1 cell lines to interfere VRK1 expression. Western blot was used to detect the interference efficiency of VRK1 siRNA and BANF1 expression in esophageal carcinoma cells after siRNA interference. CCK-8 and flow cytometry were performed to detect the effect of VRK1 expression on cell proliferation. Transwell assay was used to observe the changes of cell migration ability. Results After VRK1 siRNA transfection, VRK1 expression were down-regulated for 62.40% and 52.14%, and BANF1 protein expression were down-regulated significantly for 24.51% and 52.87% in EC109 and EC1 cell lines, respectively. The proliferation of EC109 and EC1 cell lines were decreased 12h after transfection, with the highest inhibition rate at 36h(19.41% and 20.10%). The cells percentages in G2 and G1 phases were decreased while that in S phase was increased after down-regulation of VRK1 and BANF1 expression. The number of cell migration was decreased in the experimental group, compared with control group (P < 0.01). Conclusion Down-regulation of VRK1 expression by siRNA could inhibit the proliferation and migration abilities of esophageal squamous carcinoma cells, which may be achieved by down-regulating BANF1 expression.

Microbiology: A census of oral ecosystems A new resource for consolidating oral microbiome data will help researchers explore the relationship between these commensal communities and the health of their hosts. Numerous studies have highlighted apparent connections between alterations in the microbial communities within the human mouth and medical conditions including diabetes and cancer. A recent article from researchers led by Liao Ga at Sichuan University describes the launch of the Oral Microbiome Bank of China, an effort to study such connections by profiling specimens from individuals from across the country. The database currently houses detailed information on 289 bacterial strains and the samples from which they were obtained. The authors are now looking to analyze these data to gain insights into the structure and function of oral ecosystems, and to further expand this database as a resource for Chinese microbiome research.

The pathogenic mechanisms by which oral microbial communities affect the occurrence and development of dental caries remain unclear. Applications that make use of high⁃through put sequencing technologies and metaomics approaches to research dental caries etiology can provide new ideas about disease prevention and treatment. In this arti⁃ cle, we review advanced research presented in metaomics studies, including genomic, metagenomic, metatranscriptomic, metaproteomic and metabolomics studies of dental caries.

The text should be set to 1 line spacing. The abstract should be centred across the page, indented 17 mm from the left and right page margins and justified. It should not normally exceed 200 words The titanium alloy called “strategic metal” is a typical refractory material that causes high temperature and vibration during cutting due to its high strength, low thermal conductivity and low elastic modulus. In the processing process, the tool wear is serious, and the accompanying cutting heat and cutting vibration are coupled to each other and change with time. Studying the temperature and vibration characteristics in the processing process is conducive to further understanding of cutting mechanism, better controlling temperature and vibration, improving cutting processing quality and reducing production cost. This paper reviews the current situation of cutting temperature and cutting vibration at home and abroad. Scholars focus on the influence of cutting factors on temperature and vibration, based on finite element simulation and mathematical modeling, and the research on temperature and vibration coupling of titanium alloy cutting should be further strengthened.

Tumor metastasis is the most important biological feature of a malignant tumor. It is also a complex process involving multi-step, multi-gene, and multi-products. Tumor cell-derived exosomes are vesicles secreted by tumor cells, containing proteins, lipids, noncoding RNA, and other components. MicroRNA (miRNA) of tumor cell-derived exosomes affects the tumor cell microenvironment and participates in tumor metastasis by activating various signaling pathways. Here, we summarize the miRNA and its related pathways that affect many factors of tumor metastasis and discuss the role of tumor-derived miRNA in the treatment and prevention of tumor metastasis. We also conclude the targets of tumor-derived miRNA in recent years. This article can provide new ideas for the development of tumor metastasis targeting drugs in the future.