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The development of nuclear reactor structural materials with excellent comprehensive performance is the basis of nuclear energy development, and it is one of the difficulties that have long restricted the promotion of nuclear energy. Multiprincipal element alloys(MEAs) have been recognized as candidate materials for advanced reactor structural materials due to their good irradiation resistance and mechanical properties, which has expanded a broad space for the design of new radiation-resistant materials. In recent years, the research on the irradiation damage of multiprincipal element alloys has tried to reveal the influence of some factors and characteristics of multiprincipal element alloys on the formation and evolution of defects in the irradiation process. For example, the type, number and concentration of alloying elements, lattice distortion, chemical short range order, etc. Although some existing research results show that the above factors can improve the resistance of multiprincipal element alloys to irradiation damage, under different irradiation conditions, the influence mechanism of the above factors on the formation and evolution of defects in multiprincipal element alloys is quite different, and it is difficult to draw generalization conclusions. Focusing on the four aspects of irradiation swelling, helium bubble formation, irradiation-induced element segregation and phase transition, irradiation hardening of FCC and BCC systems.The research progress of multiprincipal element alloys in irradiation damage in recent years was reviewed, the mechanism of action of multiprincipal element alloys to improve radiation resistance was summarized.And based on this, the future research directions for multiprincipal element alloys used in nuclear power structures were prospected, including tuning short-range order, high-entropy ceramics, additive manufacturing technology, accelerating development of new materials by integrating high-throughput computing with machine learning, etc. Finally, it is pointed out that new radiation-resistance MEAs must be designed based on the actual environment of material service from the perspective of composition design.

ObjectiveTo analyze the characteristics of HIV-1 subtypes and drug-resistance mutation sites among HIV-infected patients who received high-efficiency antiretroviral therapy but failed.MethodsA total of 130 plasma samples were collected from the patients who received antiviral treatment for 6 months in Taizhou City of Zhejiang Province in 2021 but failed the treatment and the viral load was ≥1 000 copies·mL-1. Nucleic acid in the samples was extracted， and the pol gene was amplified by nested reverse transcription PCR. After next-generation sequencing， online tools were used to compare and analyze the subtypes and drug-resistant mutation sites.ResultsA total of 110 samples were successfully sequenced. The main HIV-1 subtype was CRF01_AE， accounting for 42.72% （47 cases）， followed by CRF07_BC， 35.45% （39 cases）； CRF08_BC， 10.00% （11 cases）； CRF85_BC ， 8.18% （9）； and a small number of B subtype， 1.81% （2 cases） and C subtype， 1.81% （2 cases）. The online tool comparison showed that there were 67 cases with mutations of drug-resistance sites and 61 cases with drug-resistance. The mutation sites were mainly M184V， K103N， K65R and V181C， and the mutation rates were 20.00% （22 cases）， 10.91% （12 cases）， 8.18% （9 cases） and 8.18% （9 cases）， respectively. These mutation sites caused different degrees of resistance to nucleoside reverse transcriptase inhibitors （NRTI）， non- nucleoside reverse transcriptase inhibitors （NNRTI） and protease inhibitors （PI）， including 45 cases of NRTI， 61 cases of NNRTI and 2 cases of PI resistance.ConclusionThe HIV infected people who fail the treatment in Taizhou are mainly with the subtypes CRF01_AE and CRF07_BC. The rate of drug-resistance mutation is at a moderate level， mainly due to the mutation of NRTI and NNRTI drug-resistance sites， and a small number of PI drug-resistance sites. Therefore， the antiviral treatment plan for HIV infected people should be reasonably adjusted， and the detection of drug-resistance mutation sites should be strengthened to avoid the generation of transmissible drug-resistance strains.

ObjectiveWe examined the principal respiratory pathogens in patients with acute respiratory tract infection in Taizhou， Zhejiang Province during 2020‒2021 to provide evidence for prevention， diagnosis and treatment of acute respiratory tract infection.MethodsFrom September 2020 to August 2021， a total of 2 831 cases with acute respiratory tract infection were collected from two influenza sentinel surveillance hospitals in Taizhou， which had then received the examination of 22 respiratory pathogens by multiple fluorescence quantitative PCR.ResultsThe total positive rate of respiratory pathogens in 2 831 samples was 14.13%， among which enterovirus （7.77%） and respiratory syncytial virus （1.59%） were the principal pathogens. Except enterovirus， there was no significant difference in the positive rate of pathogens detected by gender（P>0.05）. Moreover， there was significant difference in pathogens by age （P

ObjectiveTo determine the prevalence of hepatitis C virus （HCV） infection and identify the underlying risk factors among drug users in Taizhou City of Zhejiang Province during 2009‒2020.MethodsA consecutive cross-sectional survey was conducted. A total of 400 drug users in correctional settings were randomly selected from April to August. The drug users were interviewed with a questionnaire to collect demographic characteristics， AIDS-related knowledge， detoxification service， drug use， and sexual behavior. Blood samples were then collected for anti-HCV antibody testing. Chi-square test and multivariate conditional logistic regression were used.ResultsA total of 5 042 drug users were included in this study. Seroprevalence of HCV was determined to be 22.7%. From 2009 to 2019， the seroprevalence showed a significant downward trend， from 34.9% to 8.8% （χ2=221.025， P

Catalytic combustion is one of the most effective purification technologies to remove soot particles from diesel engine exhaust. In order to improve the mobility of atoms on the catalyst surface and the low-temperature oxidation-reduction ability of the catalyst, the catalytic combustion performance of soot was studied by using alkali metal K-supported SnxCe1-xO2 catalyst. The SnxC1-xO2 catalyst was obtained by doping Sn and Ce according to the ratio of different substances by co-precipitation method. The activity of the catalyst was evaluated in a micro fixed bed temperature programmed reactor, and it was found that the catalyst had the best catalytic performance when nsn:n Ce = 4:6. Then, a series of xK/Sn-Ce catalysts with higher activity were prepared by impregnation, and characterized by XRD, XPS, H2-TPR, and O2-TPD. The results showed that the concentration of active oxygen on the surface of loading K was increased, the oxygen transfer rate was accelerated, and the redox ability was im-proved. When the K loading was 15% (x = 15%), the catalyst had the best removal effect on soot, the selectivity of CO2 in the product reached 94.3%, and the T90 temperature was °C. This research provided an important reference for the design of efficient soot combustion catalysts. [ABSTRACT FROM AUTHOR]

The erbium-trium aluminum garnet (Er:YAG) is a short-pulse laser that can be used for hard tissue ablation, soft tissue debridement and root canal decontamination. It can be effectively used in deciduous teeth removal, resin bonding, superordinate teeth extraction, lingual lacunae extension, root canal washing and other aspects. Because the operation is painless, it is more acceptable to children, hence it is very common in pediatric stomatology application research. This article reviews the application of Er:YAG in pediatric stomatology from the above aspects. [ABSTRACT FROM AUTHOR]

Indium antimonide (InSb) materials have been widely used in infrared photoelectric detectors and other fields because of their special properties. With the development of larger arrays of mid-infrared focal plane detectors and a growing demand for low-cost InSb infrared detectors, the desired size for the InSb wafers also increases. In this paper, a new structure of graphite rest and high precision low damage single line cutting were combined to develop a 5 inch InSb crystal oriented segmentation. Low damage edge chamfering techniques while optimizing grinding parameters were used to improve the grinding of 5 inch InSb wafers. An optimized mounting process were used to further improve the flatness of polished 5 inch InSb wafers. Furthermore, the pH value and polishing solution ratio were optimized to improve the surface quality of 5 inch InSb wafers. At the same time, the crystal orientation and deviation, polished surface macroscopic quality, geometric parameters, surface roughness and lattice quality of 5 inch InSb wafers were analyzed using an X-ray crystal orientation instrument and atomic force microscope. The test results show that, high quality 5 inch InSb wafers can be created more readily by this newly optimized process, helping to meet the current demand for InSb materials in IR detectors and other fields. [ABSTRACT FROM AUTHOR]

Main factors affecting the battery temperature in a mini-bus equipped with start-stop system are analyzed and a scheme is devised of using the temperature of battery negative electrode and the water temperature of engine to calculate the equivalent temperature of battery. A model for battery temperature is built with ASCET and is integrated into engine control unit ( ECU). The results of test show that the battery temperature model built can effectively substitute electronic battery sensor in terms of the monitoring and diagnosis of battery temperature for achieving the goal of raising the integration degree of ECU function and lowering the cost of start-stop system. [ABSTRACT FROM AUTHOR]

The start-stop system stops the engine under idling condition for saving energy, reducing emission and lowering noise. In this paper, the development background, structure and principle, key components and data communication of a mainstream start-stop system are presented. The basic idea of its control strategy is elaborated , and the calculations on the model built and tests are conducted to analyze the effects of start-stop system on the drivability, fuel economy and emission of vehicle. The results show that using start-stop system can reduce the fuel consumption per 100km by 3% to 6% and lower the emissions of major pollutants by 5% to 20%. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the compatibility laws of effective-component compatibility of Bufei Yishen formula III (ECC-BYF III) in regulating mucus hypersecretion of chronic obstructive pulmonary disease (COPD)., Methods: According to the efficacy of the original Chinese medicine, the components of ECC-BYF III were divided into four categories: Buqi (Ginsenoside Rh1+Astragaloside), Bushen (Icariin), Huatan (Nobiletin), and Huoxue (Paeonol). The four categories were divided into 14 groups based on the method of mathematical permutation. (1) The rats were divided into control group, model group, ECC-BYF III, and different components compatibility groups according to the random number table, totaling 17 groups. COPD rat model in stable phase was established by cigarette smoke exposure combined with repeated bacterial infections. The corresponding drugs were given by gavage at the 9th week of modeling, and the samples were collected at the end of the 16th week. The levels of matrix metalloproteinase-9 (MMP-9) and tissue inhibitors of metalloproteinase 1 (TIMP-1) in serum and bronchoalveolar lavage fluid (BALF), and the levels of mucin (MUC) 5AC in lung tissue and BALF were detected by enzyme linked immunosorbent assay (ELISA). (2) Human lung epithelial cells BEAS-2B were divided into blank group, model group, and different components compatibility groups. Hypoxia-induced mucus hypersecretion model of human lung epithelial cells BEAS-2B was established 4 hours after corresponding drug pretreatment. The mRNA expressions of MUC5AC, MUC5B, and MUC1 were detected by quantitative polymerase chain reaction (PCR). The mucus secretion indexes of rats and BEAS-2B cells were evaluated by Region (R) value comprehensive evaluation method., Results: (1) Compared with the control group, MMP-9 in serum and BALF from the model group were significantly increased, the level of TIMP-1 was significantly decreased, and MUC5AC in lung tissue and BALF were significantly increased. The results of R value comprehensive evaluation showed that except for the Buqi and Bushen groups, ECC-BYF III and other components compatibility groups significantly corrected mucus hypersecretion in COPD rats, ECC-BYF III, Bushen Quxie, Fuzheng Huatan, and Quxie groups were much better (R values were 2.15±0.42, 2.11±0.23, 2.16±0.23 and 2.16±0.55, respectively), compared with the model group (R value: 3.00±0.00), the differences were statistically significant (all P < 0.05). (2) Compared with the blank group, the mRNA expressions of MUC5AC, MUC5B, and MUC1 increased in the model group. But different components compatibility groups had no significant effects on the mucus secretion of BEAS-2B cells. (3) The comprehensive evaluation results of R value about each in vivo and in vitro index showed that ECC-BYF III, Huoxue, Quxie, Bushen Huoxue, Fuzheng Huatan, Buqi Quxie groups significantly corrected the mucus hypersecretion (R values were 2.30±0.43, 2.33±0.44, 2.12±0.68, 2.27±0.64, 2.24±0.27 and 2.29±0.47, respectively), compared with the model group (R value: 3.00±0.00), the difference was statistically significant (all P < 0.01). The order was: Quxie > Fuzheng Huatan > Bushen Huoxue > Buqi Quxie > ECC-BYF III > Huoxue., Conclusions: Different components compatibility of ECC-BYF III had different effects on COPD mucus secretion. The components containing Huatan (Nobiletin) or Huoxue (Paeonol) showed a better inhibitory effect on mucus secretion.