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An experimental study on the recovery of phosphorus resource was carried out for the resource application of sludge residue. The effects of acid species and different leaching conditions on the leaching of phosphorus from sludge residue were systematically analyzed，and the effects of pH and n（Mg）∶n（N）∶n（P） on the synthesis of struvite from the solution containing phosphorus were investigated. The results showed that the leaching rate of phosphorus from sludge residue could reach 96.9% under the conditions of liquid/solid ratio of 20 mL/g，hydrochloric acid concentration of 0.4 mol/L and leaching time of 4 h. Moreover，the crystallization rate of the phosphorus purification solution purified by cation exchange resin could reach 98.1% at pH=10，n（Mg）∶n（N）∶n（P）=1.2∶1.2∶1，and the heavy metal content in the obtained struvite met the standard limit of Organic and Inorganic Compound Fertilizer （GB/T 18877-2020）. In summary，79% of phosphorus in sludge residue could be recovered after phosphorus extraction，purification and crystallization.

Objective Through a pain study of buccal gingival mucosa sensitivity of the mandible, the corresponding sensitive area of pain was determined, which provided the basis for reducing the pain and discomfort of oral diagnosis and treatment. Methods 400 patients with mandibular tooth extraction in the outpatient department of stomatology were selected. During tooth extraction, articaine epinephrine injection was used for infiltration anesthesia. The injection needle size was 0.3 mm × 21 mm, and the injection site was about 5 mm away from the buccal gingival margin. The pain degree of the patients was recorded. The data were statistically analyzed using the modified International pain classification method. Results Among the 400 patients who underwent mandible extraction, 75% (300 patients) graded their pain from painless to moderate, and 25% (100 patients) reported moderate to severe and severe pain. Of those in the moderate to severe and severe groups, 50% and 42% reported pain in the central and lateral incisors, respectively, and 38% were in the canine group. When comparing the moderate to severe and the severe groups, 16% and 10% were in the bicuspid group, 16% and 12% and 16% were in the molar group, respectively . There were significant differences in the pain sensitivity of different teeth positions (χ2=54.203, P < 0.001). The proportion of moderate to severe and severe pain in the anterior teeth group was higher than it was in the posterior teeth group (χ2=55.555, P < 0.001). There were significant differences in the pain sensitivity of different ages (χ2=96.501, P=0.000), and there was a positive correlation between pain and age (r=0.465, P < 0.001). The proportion of women with at least a moderate degree of pain was higher than that of men (χ2=12.298, P=0.031). Conclusion The sensitivity of the buccal gingival mucosa to pain is different in different positions of the mandible. The sensitivity of the anterior gingiva is higher than that of the posterior gingiva. Age is positively correlated with the degree of pain. Further, compared with men, women are more sensitive to pain.

In order to make the V-belt CVT match the Racing Baja condition and engine characteristics， its key parameters are optimized. A V-belt CVT mechanical model is established， and the CVT speed regulation characteristics are analyzed and simulated in Matlab. The genetic algorithm is used to optimize the key parameters of CVT with the aim of improving the power. The bench is set up for test verification. The test results show that the simulation results are basically consistent with the test data. The CVT transmission ratio changes according to the actual working conditions， and the engine always works in the peak torque and power corresponding speed range (2 800 ~3 600 r/min)， and the vehicle power performance is significantly improved. This study has a certain guiding role in the parameter matching and optimization of V-belt CVT.

Taking coupled non-smooth Bohoffer-Van der Pol (BVP) system with periodic excitation as an example, the difference of magnitude between periodic excitation frequency and natural frequency of system was investigated. The difference of magnitude was the coupling effect of two time scales in frequency domain. Because the excitation frequency was much lower than the natural frequency of system, the whole excitation term was considered as a slow-varying parameter. The generalized equilibrium points and stabilities of system were obtained when the slow-varying parameter varied. The system had periodic bursting behavior when the value of parameters were appropriate. By combining the fast-slow analysis method and transformed phase portraits, the complex dynamical behavior as well as related mechanisms were analyzed when the slow-varying parameter crossed different bifurcation points and non-smooth boundary. [ABSTRACT FROM AUTHOR]

An underwater driving system requires a high-pressure solenoid valve with a high flow rate and high speed. A novel solenoid valve with parallel spools was proposed to meet the demand. The opening response time of the solenoid valve had a great influence on the performance of the underwater driving system. In order to reduce the opening response time of the novel parallel-spool pneumatic pilot operated high-pressure solenoid valve, an optimal design method was proposed. First, a mathematical model of the opening process of the valve was built up. A prediction model of the opening response time of the valve was deduced from the mathematical model established. In the prediction model, the opening response time was subdivided into four parts including the armature preparation time, the armature movement time, the exhaust time of the control chamber, and the movement time of the main valve spool. The corresponding formulas to solve the response time were derived. Secondly, based on the prediction model, an optimization program of the parameters of the pilot valve was designed by using a Multi-population Genetic Algorithm which was developed from a Standard Genetic Algorithm. The optimization program was written in MATLAB programming language using the Sheffield Genetic Algorithm Toolbox. To reduce the opening response time, four key parameters including the nominal diameter of the pilot valve, the radius of the armature, the width of the coil, and the length of the coil needed to be optimized. After optimization, the opening response time of the valve was 47.6 ms which was reduced by 14%. The impact of the key parameters on the opening response time of the valve was discussed respectively by using the optimization program. With the increase of the nominal diameter of the pilot valve and the length of the coil, the opening response time of the valve first decreases and then increases. Namely, there are optimal values for those two parameters. The opening response time fluctuated with the increase of the diameter of the armature, but the amplitude was small. Along with the rising of the width of the coil, response time was slightly decreased at first, then increased rapidly. On the basis of the analysis, multiple local extremums were found. That will result in many difficulties to the algorithm in converging to the global extremum. The optimization of the solenoid valve was an optimization with multiple local extremums. The optimization algorithm should possess a good capability to search for a global optimum. The optimization results obtained by using the Multi-population Genetic Algorithm showed that the optimization program designed was effective. Compared with the Standard Genetic Algorithm, the Multi-population Genetic Algorithm performed much better than the Standard Genetic Algorithm in avoiding the premature phenomenon, and its convergence speed was faster. At last, a test prototype of the novel valve was processed based on the optimized parameters and an opening response test of the valve was carried out. The experimental results showed that the opening response time tested was 48.3 ms at the pressure of 10 MPa, that was 1.5% larger than optimization result. The error between the experiment and the optimization was small. After optimization, the solenoid valve can meet the demands of the underwater driving system well. [ABSTRACT FROM AUTHOR]

Tumor is a serious threat to human health. At present, surgical resection, chemoradiotherapy, targeted therapy and immunotherapy are the main therapeutic strategies. Monoclonal antibody has gradually become an indispensable drug type in the clinical treatment of cancer due to its high efficiency and low toxicity. Phage antibody library technology (PALT) is a novel monoclonal antibody preparation technique. The recombinant immunoglobulin variable region of heavy chain (VH)/variable region of light chain (VL) gene is integrated into the phage vector, and the antibody is expressed on the phage surface in the form of fusion protein to obtain a diverse antibody library. Through the process of adsorption-elution-amplification, the antibody library can be screened to obtain the antibody molecule with specific binding antigen as well as its gene sequence. PALT has the advantages of short antibody production cycle, strong plasticity of antibody structure, large antibody yield, high diversity and direct production of humanized antibodies. It has been used in screening tumor markers and preparation of antibody drugs for breast cancer, gastric cancer, lung cancer and liver cancer. This article reviews the recent progress and the application of PALT in tumor therapy.

Glioma is the most common primary brain tumor, accounting for 81% of intracranial tumors. The diagnosis and prognosis assessment of glioma are mainly based on imaging. However, imaging cannot be fully used as the basis for diagnosis and prognosis assessment due to the infiltrative growth characteristics of glioma. Therefore, the discovery and identification of novel biomarkers is particularly important for the diagnosis, treatment and prognosis assessment of glioma. The latest findings suggest that a variety of biomarkers in the tissues and blood of glioma patients can be used for the auxiliary diagnosis and prognosis assessment of glioma. Among them, IDH1 / 2 gene mutation, BRAF gene mutation and fusion, p53 gene mutation, increased telomerase activity, circulating tumor cells and non-coding RNA can be used as diagnostic markers. Prognostic markers include 1p/19p codeletion, MGMT gene promoter methylation, upregulation of matrix metalloproteinase-28, insulin-like growth factor-binding protein-2 and CD26, and downregulation of Smad4. This review highlights the latest advances of biomarkers in the diagnosis and prognosis assessment of glioma.

Malignant tumors are diseases that seriously threaten human health and social development. Traditional tumor therapies such as surgery, radiotherapy, chemotherapy and targeted therapy cannot fully meet the needs of clinical treatment, and emerging immunotherapy has become a research hotspot in the field of tumor treatment. Immune checkpoint inhibitors (ICIs) have been approved as a tumor immunotherapy method for the treatment of various tumors, such as lung cancer, liver cancer, stomach cancer and colorectal cancer, etc. However, during the clinical use of ICIs, only a small number of patients experienced durable responses, which also led to drug resistance and adverse reactions. Therefore, the identification and development of predictive biomarkers is crucial to improve the therapeutic efficacy of ICIs. The predictive biomarkers of tumor ICIs mainly include tumor biomarkers, tumor microenvironment biomarkers, circulation-related biomarkers, host environmental biomarkers and combinatorial biomarkers. They are of great significance for screening, individualized treatment and prognosis evaluation of tumor patients. This article reviews the advances of predictive markers for tumor ICIs therapy.

The estimated new cases of breast cancer (BC) patients were 2.26 million in 2020, which accounted for 11.7% of all cancer patients, making it the most prevalent cancer worldwide. Early detection, diagnosis and treatment are crucial to reduce the mortality, and improve the prognosis of BC patients. Despite the widespread use of mammography screening as a tool for BC screening, the false positive, radiation, and overdiagnosis are still pressing issues that need to be addressed. Therefore, it is urgent to develop accessible, stable, and reliable biomarkers for non-invasive screening and diagnosis of BC. Recent studies indicated that the circulating tumor cell DNA (ctDNA), carcinoembryonic antigen (CEA), carbohydrate antigen 15-3 (CA15-3), extracellular vesicles (EV), circulating miRNAs and BRCA gene from blood, and the phospholipid, miRNAs, hypnone and hexadecane from urine, nipple aspirate fluid (NAF) and volatile organic compounds (VOCs) in exhaled gas were closely related to the early screening and diagnosis of BC. This review summarizes the advances of the above biomarkers in the early screening and diagnosis of BC.

This study attempts to develop a reference substance for the live bacteria count of Streptococcicosis live vaccines in order to evaluate the validity of live bacterial count in inspection and testing. We prepared a batch of live Streptococcus suis reference substance for live bacterial count, tested their physical property, purity, vacuum degree, remaining moisture, and determined their homogeneity, thermal stability and transportation stability. Moreover, we organized collaborative calibration to assign count values to the reference substance and determine the shelf life of the reference substance in 12 months. The results showed that the physical property, the purity, the remaining moisture and the vacuum degree of the reference substance were all in compliance with the requirements of the Chinese Veterinary Pharmacopoeia. The homogeneity test showed that the coefficient of variation of the count of the reference substance was less than 10%, indicating a good homogeneity. Transportation stability test showed that the reference substance remained active after 72 h transportation in summer and winter with the package of styrofoam boxes and ice packs. Thermal stability test showed that the reference substance could be stored for up to 3 months at -20 °C, or up to 21 days at 4 °C. According to the collaborative calibration, the reference vaccine was assigned a count value range of (8.5-12.1)×107 CFU/ampoule. The shelf life test showed that the reference substance was stable for 12 months when stored at -70 °C. The reference substance could provide a reference for the live bacterial count of Streptococcicosis live vaccines. Moreover, it could also be used as a reference to evaluate the quality of corresponding agar media.

Objective To detect and analyze the plasma levels and immunoactivities of different forms of circulating-free DNA (cfDNA) in systemic lupus erythematosus (SLE) patients. Methods The study enrolled 58 patients with SLE, 66 patients with other autoimmune diseases (non-SLE) and 60 healthy individuals. Total cfDNA, exosome cfDNA and immune complex cfDNA were extracted from the plasma and detected using a fluorescence method. Overall methylation levels of cfDNA were measured. Macrophages and dendritic cells induced in vitro were co-cultured with exosomes or immune complexes derived from SLE patients pre-treated with deoxyribonuclease 1-like 3(DNASE1L3) or immunoglobulin G (IgG) specific degradation enzyme or none. Then, cytokines and cell surface activation markers were detected by the multiple fluorescent microsphere assay. Results Among the three groups, SLE patients had the highest levels of exosomes and immune complex cfDNA, followed by non-SLE patients, and no significant differences were found in the simple cfDNA. The methylation levels of different types of cfDNA (except simple cfDNA) in the plasma of SLE patients were significantly lower than that of the non-SLE group and healthy individuals. Non-SLE patients and healthy individuals presented no significant differences for the methylation levels of all cfDNA types. After DNASE1L3 and IgG enzyme treatment, the macrophages and dendritic cells stimulated by exosomes and immune complex cfDNA secreted significantly lower levels of cytokines including MIP-1a, MIP-1b, IL-4, IL-1β, IL-2, IL-1ra, MCP-1, IL-6, IL-9, IL-8, TNF-α and IFN-α. Compared with IgG enzyme treatment, DNASE1L3-treated exosomes and immune complex induced the lower level of cytokines secretion. The expression of CD80, CD86 and CD40 on the surfaces of macrophages and dendritic cells stimulated with exosomes and immune complexes pre-treated with DNASE1L3 enzyme were significantly reduced, but the expression of CD86 on the macrophages was slightly changed. The expression of CD80, CD86 and CD40 showed no difference in the two types of cells stimulated with exosomes and immune complexes pre-treated with IgG enzymes or none, but an overall downward trend existed indeed. Conclusion Exosomes and immune complex cfDNA increase significantly in the plasma of SLE patients, and they can stimulate strong responses of macrophages and dendritic cells.

Objective To detect the levels of cell-bound complement activation product (C4d) and immunoglobulins (IgG and IgM) on T and B lymphocytes in patients with systemic lupus erythematosus (SLE), and to evaluate the relationships between C4d and immunoglobulins (Ig) on lymphocytes, and finally to evaluate their diagnostic value for SLE. Methods A cross-sectional study including 142 SLE patients, 144 patients with other non-SLE autoimmune diseases and 100 healthy individuals was conducted. C4d and immunoglobulins on peripheral T and B lymphocytes (T-C4d, B-C4d, T-Ig and B-Ig) were measured by flow cytometry. In vitro immunobinding experiment was performed to characterize serum Ig from SLE patients to generate T-C4d, B-C4d, T-Ig and B-Ig. ANA, anti-dsDNA, anti-Smith antibody and other biomarkers were measured. Area under the receiver operating characteristic curve (AUC), nonparametric tests, partial correlation analysis, sensitivity and specificity were used for statistical analysis. Results Levels of T-C4d, B-C4d, T-Ig and B-Ig were found to be highest in SLE patients. Levels of T-C4d, B-C4d, T-Ig and B-Ig in non-SLE patients were also significantly higher than those in healthy individuals. T-C4d was positively correlated with T-Ig (r=0.587), as well as B-C4d vs B-Ig (r=0.734). Purified Ig from SLE plasma generated higher levels of T-C4d, B-C4d, T-Ig and B-Ig than Ig-removed SLE plasma. AUC of T-C4d, B-C4d, T-Ig and B-Ig were 0.733, 0.834, 0.707 and 0.825, respectively. Compared with anti-dsDNA antibody (38.7%), the sensitivity for SLE diagnosis increased significantly when the combination of T-C4d, B-C4d, T-Ig and B-Ig (85.2%) was made. Conclusion The autoantibody is a key factor for cell-bound C4d formation, and T-C4d, B-C4d, T-Ig and B-Ig may be reliable indicators for the diagnosis of SLE.

Objective: To understand the threshold of Breteau Index (BI) on Dengue fever outbreak in Guangzhou., Methods: Dengue cases from Guangzhou during 2006 to 2012 in the National Infectious Disease Report and Management System were collected and described. Receiver-operating characteristic (ROC) curve was used to judge the threshold of BI on the outbreaks of Dengue fever., Results: A total of 1 038 local cases were reported from 2006 to 2012 in Guangzhou city, with a total of 71 outbreaks and 259 sporadic episodes. Data from the ROC curve analysis showed that the highest Youden index that BI predicting Dengue fever outbreaks or sporadic were 6.4 and 9.5, respectively. When using BI = 6.4 in predicting the sporadic case of Dengue, sensitivity and specificity were 67.8% , 79.1% , respectively. When using BI = 9.5 in predicting the outbreaks of Dengue, sensitivity and specificity were 81.7%, 90.9%, respectively., Conclusion: Both BI = 5.0 and BI = 9.5 showed effects on predicting the nature of sporadic or outbreak on Dengue, suggesting that the threshold need to be monitored, according to the purpose of control and availability of manpower, in order to get better sensitivity and specificity.

PACS (Picture Archiving and Communication Systems) is the hot spot of hospital information construction research and DICOM (Digital Imaging and Communication in Medicine) is the international standard about data compression and translation of medical image and relational information. Supporting DICOM standard is the necessary condition for medical image devices to join into PACS net. In making reforms in the old fashioned medical devices in hospitals, it is necessary to add DICOM interface for medical image devices. In this paper, DICOM information model is introduced and software system is implemented with Visual C + + programming, especially the writing, reading and C-STORE service in communication function are introduced in detail.

Shear stresses acting on vascular endothelial cells due to blood fluid flow play an vital role in regulating their morphology, structure, growth rate and functions. The change in morphology is an instinctive response to biomechanical environment and is an indicator for the functional changes in the cells. In this paper, the morphological research literatures of endothelial cells in the recent years are reviewed and the common morphological parameters are described in detail. At the end, the difficulties of quantitative study of endothelial cell morphology and the future direction of morphological parameters research are also discussed.