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Serological testing can be a powerful complementary approach to achieve timely diagnosis of severe acute respiratory coronavirus 2 (SARS-CoV-2) infection, along with nucleic acid detection. Immunoglobulin (Ig) A antibodies are less frequently utilized to detect SARS-CoV-2 infection than IgM and IgG antibodies, even though IgA antibodies play an important role in protective immunity against SARS-CoV-2. This review discusses the differences in kinetics and assay performance between IgA and IgM antibodies and the factors influencing antibody responses. It highlights the potential usefulness of analyzing IgA antibodies for the early detection of SARS-CoV-2 infection. The early appearance of IgA and the high sensitivity of IgA-based immunoassays can aid in diagnosing coronavirus disease 2019. However, because of cross-reactivity, it is important to recognize the only moderate specificity of the early detection of SARS-CoV-2 IgA antibodies against spike antigens. Either the analysis of antibodies targeting the nucleocapsid antigen or a combination of antibodies against the nucleocapsid and spike antigens may strengthen the accuracy of serological evaluation.

With the global increase in the aging population, the pain management in elderly patients has becoming a great concern. This paper reviewed the guideline related the pain management for the elderly. The quality and rating of guidelines were evaluated by using AGREE Ⅱ, and the recommendations for pain management care were summarized. It provides a basis for standardizing the pain management in the elderly, so that clinical practitioners can form the pain management guidelines according to the characteristics of the elderly in China. (随着人口老龄化趋势加重, 老年人群的疼痛管理尤为重要。本研究通过对老年人疼痛相关指南的筛查, 使用指南研究与评价工具(AGREEⅡ)进行质量评价、评级, 形成推荐意见的汇总, 旨在为规范老年疼痛管理提供依据, 以及为制定符合我国老年人特点的老年疼痛管理指南提供参考。)

Atherosclerosis, a chronic inflammatory disease of the arterial wall, serves as the pathophysiological basis for ischemic stroke and coronary heart disease, and stands as the primary cause of cardiovascular and cerebrovascular comorbidity. Both the heart and brain share similar risk factors, including hypertension, hyperlipidemia and diabetes, and so on. Furthermore, most patients with cardiovascular and cerebrovascular comorbidity experience more severe disease and poorer prognosis. This article comprehensively reviews research progress in the pathophysiology of cardiovascular and cerebrovascular comorbidity, their related risk factors, and proposes the strategies of "synchronous treatment for brain and heart" to offer new insights for the prevention and management of cardiovascular and cerebrovascular comorbidity.

In view of the high viscosity, poor fluidity and high transportation cost of heavy oil, water-annular transportation is an effective solution to realize the flow drag reduction during heavy oil transportation, but the large density difference between oil and water leads to the instability of water annular. For this reason, a superhydrophilic surface is introduced to improve the stability of the water annular in the pipeline and reduce the transportation resistance of heavy oil. Besides, the enhancement of heavy oil transportation by superhydrophilic surface was verified through numerical simulation and experiments in combination. Meanwhile, the effect of various factors on oil-water flow, oil-water distribution and pressure drop in pipelines during water-annular transportation were analyzed. The research results show that the superhydrophilic surface could improve the stability of water annular in the water-annular transportation system of heavy oil, with the obvious effect of flow drag reduction. Compared with the water-annular white oil transportation by ordinary pipeline, the flow drag reduction of over 17.49% can be realized, the maximum flow drag reduction is up to 50.15%, and the enhancement is within 9.06%-39.09% after the superhydrophilic surface is introduced. Compared with the white oil transportation without water annular, the flow drag reduction can reach 72.02%-78.21%. Generally, the superhydrophilic surface could significantly enhance water-annular heavy oil transportation with promising application prospects, capable of effectively improving the applicability of water-annular heavy oil transportation technology.

Aiming at the problem of underwater attack and defense in typical situations, a mathematical model of three-party attack and defense problem composed of torpedo, submarines and anti-torpedo torpedo is established. Under the condition of considering three-party game confrontation, the three-party game problem is transformed into the pursuit and escape game problem between the submarine and torpedo, and the interception and evasion game problem between the submarine launched ATT and the torpedo. Based on the optimal control theory and differential game theory, the three-party optimal game problem is studied, and the three-party game performance evaluation function is designed based on the optimal performance of the two parties of pursuit and escape and the two parties of interception and evasion. According to the optimal necessary condition of the bilateral extremum, the strategy of pursuing, escaping, blocking and avoiding in the three-party game is deduced. The effectiveness of the game strategy designed in the underwater attack and defense process is verified by simulations. The results show that the game strategy can improve the effects of submarine escape, anti-torpedo torpedo interception and torpedo attack.

ObjectiveTo establish an ultra-high performance liquid chromatography-tandem mass spectrometry method for the detection of two typical advanced glycation end products （AGEs） in bread.MethodsProtein-bound carboxymethyl lysine （CML） and carboxyethyl lysine （CEL） were used as the detection objects. Bread sample was subjected to reduction incubation， protein precipitation， addition of isotope internal standard， acid hydrolysis， nitrogen blowing， reconstitution with nonafluorovaleric acid aqueous solution， and then underwent multi-reaction monitoring to quantitative analysis.ResultsThe detection limit and quantification limit of the method were 4.5 ng/g and 20 ng/g for CML， and 0.5 ng/g and 2 ng/g for CEL. The spike recovery rates of CML and CEL were 89.62%-95.65% and 86.38%-97.17%. The linear range were 2.5-800 ng/mL and 0.25-80 ng/mL， and the coefficients of determination were both above 0.999.ConclusionThe method was accurate and sensitive， and could meet the detection requirements of AGEs in bread.

Objective To establish a nomogram predicting model for assessing the risk factors of peripherally inserted central catheter (PICC) related upper extremity deep venous thrombosis (DVT) in elderly patients, and to evaluate the discrimination and consistency of the model. Methods The clinical data of 362 elderly patients with PICC in researched hospital from January 2014 to December 2019 were retrospectively analyzed by self-design questionnaire. The incidence of catheter-related upper extremity DVT was calculated. Research subjects were divided into DVT group and non DVT group. The risk factors related to upper extremity DVT occurrence were screened by Logistic regression model, and the risk factors were included in R software to construct the risk factors of upper extremity DVT. The discrimination and consistency of the prediction model were evaluated by ROC curve and goodness-of-fit test. Results The incidence of upper extremity DVT in elderly patients over 80s with PICC was 20. 44% (74/362). The results of Logistic regression model showed that the age, malignant tumor, D-D level before catheterization and operation history during catheterization were independent risk factors for upper extremity DVT in elderly patients with PICC (P

As one of the important way for constructing smart agriculture, unmanned farms are the most attractive in nowadays, and have been explored in many countries. Generally, data, knowledge and intelligent equipment are the core elements of unmanned farms. It deeply integrates modern information technologies such as the Internet of Things, big data, cloud computing, edge computing, and artificial intelligence with agriculture to realize agricultural production information perception, quantitative decision-making, intelligent control, precise input and personalized services. In the paper, the overall technical architecture of unmanned farms is introduced, and five kinds of key technologies of unmanned farms are proposed, which include information perception and intelligent decision-making technology, precision control technology and key equipment for agriculture, automatic driving technology in agriculture, unmanned operation agricultural equipment, management and remote controlling system for unmanned farms. Furthermore, the latest research progress of the above technologies both worldwide are analyzed. Based on which, critical scientific and technological issues to be solved for developing unmanned farms in China are proposed, include unstructured environment perception of farmland, automatic drive for agriculture machinery in complex and changeable farmland environment, autonomous task assignment and path planning of unmanned agricultural machinery, autonomous cooperative operation control of unmanned agricultural machinery group. Those technologies are challenging and absolutely, and would be the most competitive commanding height in the future. The maize unmanned farm constructed in the city of Gongzhuling, Jilin province, China, was also introduced in detail. The unmanned farms is mainly composed of information perception system, unmanned agricultural equipment, management and controlling system. The perception system obtains and provides the farmland information, maize growth, pest and disease information of the farm. The unmanned agricultural machineries could complete the whole process of the maize mechanization under unattended conditions. The management and controlling system includes the basic GIS, remote controlling subsystem, precision operation management subsystem and working display system for unmanned agricultural machineries. The application of the maize unmanned farm has improved maize production efficiency (the harvesting efficiency has been increased by 3－4 times) and reduced labors. Finally, the paper summarizes the important role of the unmanned farm technology were summarized in solving the problems such as reduction of labors, analyzes the opportunities and challenges of developing unmanned farms in China, and put forward the strategic goals and ideas of developing unmanned farm in China.

Staphylococcus aureus is an important causative pathogen of bloodstream infections. An amplification assay such as real-time PCR is a sensitive, specific technique to detect S. aureus. However, it needs well-trained personnel, and costs are high. A literature review focusing on rapid and simple methods for diagnosing S. aureus was performed. The following methods were included: (a) Hybrisep in situ hybridization test, (b) T2Dx system, (c) BinaxNow Staphylococcus aureus and PBP2a, (d) Gram staining, (e) PNA FISH and QuickFISH, (f) Accelerate PhenoTM system, (g) MALDI-TOF MS, (h) BioFire FilmArray, (i) Xpert MRSA/SA. These rapid and simple methods can rapidly identify S. aureus in positive blood cultures or direct blood samples. Furthermore, BioFire FilmArray and Xpert MRSA/SA identify methicillin-resistant S. aureus (MRSA), and the Accelerate PhenoTM system can also provide antimicrobial susceptibility testing (AST) results. The rapidity and simplicity of results generated by these methods have the potential to improve patient outcomes and aid in the prevention of the emergence and transmission of MRSA.

The mode transformation of agricultural production is a common concern for China and worldwide. Currently, the level of mechanization has been significantly promoted for the agriculture sector in China and smart production becomes an inevitable trend for modern agriculture. Smart agriculture regards data, knowledge, and intelligent equipment as the core elements and integrates modern science and technology with agriculture to realize digital perception, intelligent decision-making, precise operation, and smart management in the entire process of agricultural production, thereby greatly improving labor productivity, resource utilization rate, and land output rate. This article presents the current status of agricultural production in China using rice production as an example, and analyzes the necessity, opportunities, challenges, directions, and route for the intelligent transformation of China’s agriculture. Furthermore, we propose policy suggestions to promote the intelligent development of China’s agricultural production, including (1) strengthening the research and innovation system for agricultural machinery, (2) improving the agricultural machinery promotion system, (3) optimizing the socialized service system for agricultural machinery, and (4) accelerating the construction of smart agriculture demonstration zones.

In order to reveal the influence mechanism of pore characteristics parameters of coal body on gas adsorption and diffusion, eight sets of coal samples from Ningtiaota Coal Mine were selected for experiments on pressure mercury, gas adsorption constants and initial velocity of gas dispersion, and the pore fractal characteristics of coal samples and their influence on gas adsorption and diffusion characteristics were analyzed based on Menger sponge fractal model. The results show that the pore volume of coal sample is dominated by microporous pores, followed by transitional pores, mesopores and macropores, microporous pores play a dominant role in the pore volume of coal sample, which are mainly closed and semi-open pores, and mesopores and macropores are mainly open pores. The fractal dimension D2 is linearly related to the adsorption constant a. As the fractal dimension D2 increases, the adsorption constant a gradually increases, and the initial velocity of gas diffusion gradually decreases with the increase of fractal dimension D2, and the weaker the gas dispersion performance.

In order to explore the influence of different TPMS pore structures on the mechanical properties of the porous scaffold, TPMS expressed by implicit function was used as the basic pore unit to construct the micro-porous structure. TPMS porous scaffolds with different structural characteristics were constructed by defining the distance function, And AlSi10 Mg porous scaffolds were prepared by SLM. Finite element Method（FEM） analysis and mechanical test method were used to study the influence of different pore structure characteristics on mechanical performance of porous TPMS scaffolds and analyze the influence law of different distance function k values on porosity, elastic modulus, yield strength and failure of Primitive（P） and F-RD porous structure scaffolds. Finite element analysis and experimental results show that with the increase of distance function k, the elastic modulus and yield strength of the P unit porous scaffold presented an increasing trend, However, the elastic modulus and yield strength of the FRD unit porous scaffold showed a downward trend, Moreover, Comparing to FRD unit, P unit porous scaffolds were more likely to be crushing, through the control of the TPMS types and the distance function k value, the porosity, elastic modulus and yield strength of the porous scaffold can be effectively adjusted. The results provide a basis for the design of tissue-engineered bone scaffolds.

In order to seek a lattice structure with better mechanical properties, a reverse Kagome lattice unit cell model is proposed based on the point group theory, and it is contrastively analyzed with the kagome unit cell model in the mechanical properties. The stress and strain theory is used to determine the key parameter of the reverse Kagome unit cell, which is the range of the inclination angle ω on the constraint condition of realizing the compression performance, shearing property and reaching the relative density and bearing capacity of the reverse Kagome. Combined with the finite element analyze results, it can determine the value of ω of this model under the best mechanical performance. An experiment of the reverse Kagome lattice model is performed to verify the correctness of the theoretical analysis. The research shows that when the tilt angle ω is 52°, the reverse Kagome lattice structure has the best compression resistance, and when the tilt angle ω is 38°, the shear performance of this structure is better; In terms of overall performance, the 45°inclination angle is better than the other two inclination angles.

In the application of digital model of animation scene, image restoration technology and image denoising technology are the basic tasks of practical operation, which are closely related, but there exist also essential differences. The reason is that both of them want to obtain the original image from the degraded noise image or damaged image, but generally speaking, as there is no sufficient constraint information to accurately recover the original image, both of them are unwell-posed inverse problems. Therefore, on the basis of understanding the basic content and application research status of variational partial differential equations (PDEs), this paper discusses the application value of variational PDEs in image denoising and restoration according to the image processing requirements in the digital model of animation scenes.

The aim of this study was to clarify the role of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in proliferation, migration, and invasion of malignant pleural mesothelioma (MPM) cells. The quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to detect the expression of MALAT1 in MPM cell lines. The effects of MALAT1 and miR-141-3p on the proliferation, migration, and invasion of MPM cells were studied through a series of in vitro cellular experiments. The flow cytometry was utilized to detect the cell apoptosis. The dual‐luciferase reporter assay was employed to explore the binding relationship among MALAT1, miR-141-3p, and YES-associated protein 1 (YAP1). MALAT1 was overexpressed in MPM cell lines, while its knockdown significantly inhibited the cell proliferation, migration, and invasion, and increased the number of MPM cells in the G0/G1 phase. In addition, MALAT1 could directly bind to miR-141-3p and inhibit its expression. YAP1 has been identified as a downstream target of miR-141-3p, and its expression level was inhibited by miR-141-3p. MALAT1 can be used as a competitive endogenous RNA (ceRNA) to regulate the YAP1-Hippo signaling pathway through miR-141-3p, promote the proliferation, migration, and invasion of MPM cells, and provide a new target for the therapy of MPM.

Objective To characterize the characteristics of gut microbiota and its function in the first (T1) to second trimester(T2) of pregnancy and to evaluate its association with gestational mellitus diabetes (GDM). Methods A prospective cohort study was conducted in Peking Union Medical College Hospital from May to December 2017. The pregnancies were divided into GDM group and non-GDM group (control group) according to the Results of 75 g oral glucose tolerance test at 24 to 48 weeks of gestation. Stool samples of all participants were collected in the first and the second trimester. The V4 region of the 16S rRNA gene was sequenced and analyzed. Multivariate Logistic regression analysis was used to investigate the relationship between Alpha diversity, relative abundance of intestinal flora and GDM. Results A total of 145 pregnancies, of whom 34 diagnosed with GDM (GDM group) and 111 healthy (control group) were analyzed. The Alpha diversity of the GDM group (Shannon index and Simpson index) was significantly lower than that of the control group (P < 0.05). LEfSe analysis revealed that the relative abundance of several genera was different between the 2 groups in T1 or T2. Multivariate Logistic analysis showed that Shannon index ≤6.51 (OR=3.15, 95% CI: 1.32-7.52), Simpson index ≤0.96 (OR=2.54, 95% CI: 1.09-5.89), the lower relative abundance of Alloprevotella(OR=2.65, 95% CI: 1.09-6.44) and Lachnospira(OR=3.17, 95% CI: 1.33-7.55) in the first trimester were risk factors for GDM. The pathways of LPS biosynthesis, energy metabolism, glucose metabolism and amino acid metabolism of gut microbiome revealed through the Tax4Fun analysis were significantly enriched in the GDM group in T2. Conclusions Compared with healthy controls, the functional characteristics of intestinal microflora in GDM patients during the second trimester were significantly enriched in functional pathways related to LPS synthesis, energy metabolism, glucose metabolism and amino acid metabolism. The decreases of the diversity as well as the relative abundance of some genus in the early pregnancy are the risk factors for GDM.

To explore the capacity value of a concentrating solar power (CSP) station,a method to optimize the thermal collection area and thermal storage capacity of a CSP station based on the credible capacity and levelized cost of energy (LCOE) is proposed in this paper. Firstly,generating efficiency model and economical model of CSP station are established in this paper. Secondly,the generation reliability of power generation system is calculated based on sequential Monte-Carlo method,and the particle swarm optimization (PSO) is utilized to search the credible capacity of the CSP station. Tthen the influences of solar multiple and thermal storage time on capacity credibility and LCOE of CSP station are studied. With credible capacity and levelized cost of energy as the optimization goal,weighted ideal point solution and entropy weight method are utilized to create a single objective optimization function and to determine the index weight respectively. Taking a CSP planning in the northwest as an example,using the region's real solar irradiation data,a model is established. The results show that the capacity credibility of CSP station increases monotonically with the increase of solar multiple and thermal storage time. At the same time,the levelized cost of energy decreases at the first stage and then increases at the second stage. The optimal solar multiple and thermal storage time is obtained under the constraints.

Objective To investigate the clinical features and prognosis of HIV-negative plasmablastic lymphoma (PBL) patients. Methods We collected HIV-negative PBL cases reported in our hospital and other literatures from online databases from January 1, 1997 to March 30, 2020. The data of clinical features, molecular pathology, treatment and prognosis were summarized and analyzed. Results We included 60 PBL patients, average age was 53.06±14.36 years, and most of them had relatively high Ann Arbor stage and Ki-67 expression. The average OS was 13.48±13.21 m. Kaplan-Meier curve revealed Ann Arbor stage, IPI index (3-5), B symptoms and CR in initial treatment were significantly related with patients' survival. Cox regression analysis indicated that the Ann Arbor stage and IPI index were the independent prognostic factors for patients' survival. Conclusion HIV-negative PBL mostly occurs in the middle-age and elderly patients, with advanced diagnosis stage and rapid tumor proliferation. Combination chemotherapy is the main treatment, while the therapeutic response and OS might be heterogeneous, the prognosis of most patients would be poor. The stage and IPI index are significantly related to the prognosis.

In any U-abundant semigroup with an Ehresmann transversal, two significant components R and L are introduced in this paper and described by Green’s ∼\sim -relations. Some interesting properties associated with R and L are explored and some equivalent conditions for the Ehresmann transversal to be a quasi-ideal are acquired. Finally, a spined product structure theorem is established for a U-abundant semigroup with a quasi-ideal Ehresmann transversal by means of R and L.

In order to meet the growing demand of lymphotherapists, training and patients, guidance, a specific model was designed for training manual lymphatic drainage therapy. The design and application effect of this model is described and discussed in this study. The model can easily let the operator know whether the manipulation is accurate, whether the operation pressure is stable and whether the drainage effect is satisfactory for further adjustments. The design is very close to the clinical practice and the operation of the model is simple and convenient. Preliminary application of this training model showed good effect in better understanding and mastering manipulation technique both in therapists and the patients, as well as their family members. (本研究针对当前淋巴治疗师培训及患者指导上的缺陷, 设计了一种淋巴水肿手法淋巴引流培训教具装置, 并对设计思路及使用效果加以分析。通过使用手法淋巴引流培训教具装置进行操作练习, 可以直观的感受到操作手法的准确性、操作压力的稳定性及引流操作的效果, 增强治疗师的培训成效, 提高患者或者家属掌握的可控性, 进而提升淋巴水肿治疗师培训及患者指导的应用效果。该手法淋巴引流培训教具装置操作简单方便, 应用效果显著。)

The jointed rock mass exhibits an obviously instantaneous plastic strain under fatigue loading, and thus it is imperative to establish a fatigue constitutive model of jointed rock considering instantaneous plasticity. Based on the assumption that the relationship between the plastic stress of the joint and stress follows a power function, and the accelerated fatigue strain is a second-order nonlinear viscous strain, a joint plastic fatigue component and a double-triggered nonlinear viscous fatigue composite component are proposed. Then a new elastic-plastic viscous fatigue model of jointed rock is established. The results reveal that the proposed model can accurately simulate the fatigue strain of intact rock and jointed rock. Moreover, the proposed model can simulate the stationary fatigue curve of jointed rock mass under fatigue loading, and it can also be applied in the simulation of instantaneous elastic-plastic fatigue, decelerated fatigue, constant speed fatigue and accelerated fatigue of jointed rock under non-stationary fatigue. The model fitting results show that the instantaneous fatigue plastic strain of jointed rock accounts for a large proportion of the instantaneous fatigue strain which should not be ignored. The results of this study are of great reference value in the prediction of fatigue strain and fatigue stability of jointed rock in rock engineering.

With the rapid development of science and technology, artificial intelligence(AI) is much often experimentally used in the diagnosis, treatment, and prognosis prediction of many diseases. The principle of colorectal cancer treatment has changed from simply treating tumors to prolonging the patient's survival and improving their life quality. The concept of tumor overall management has thus being developed. In this paper, the development of AI technology in the whole course management of colorectal cancer is reviewed and through which to provide an outlook of prospecting a more deeply and widely use of AI technology in the whole course management of colorectal cancer.

Existing de-anonymization technologies are mainly based on the network structure. To learn and express network structure is the key step of de-anonymization. The purpose of the user identity linkage is to detect the same user from different social networking platforms. DeepLink is a cross-social network user alignment technology. It learns the structural of the social networks and align anchor nodes through deep neural networks. DeepLink was used to identify de-anonymization social networks, and the results outperforms the traditional methods.