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Graphene-based metamaterial sensors are of significant research value for detecting food preservatives at low concentrations due to their extremely high sensitivity levels. In this work, we proposed and experimentally demonstrated an anapole resonance-based graphene metasurface (An-graphene-Ms) sensor with its conductivity altered by electrostatic doping effects for detecting and differentiating between two preservatives, sodium benzoate and potassium sorbate, in the terahertz region. Sodium benzoate, owing to its benzene ring structure, established π–π stacking interactions between the π-electrons in the benzene ring and those in graphene, amplifying the sensing effect. The amplitude changes and phase differences of the An-graphene-Ms sensor for the sodium benzoate detection were greater than those for potassium sorbate at the same concentration. Additionally, to reveal the dependence of the resonance frequency on the time delay, the measured signals were investigated using the continuous wavelet transform (CWT), and the time-frequency combination of the metasurface sensor was performed. The 2D wavelet coefficient intensity cards are effectively constructed through CWT, which also presents a more accurate approach for distinguishing and determining the concentrations of the two preservatives.

The large deuterium/tritium target is the key component to achieve high yield and high current neutron source, which is the precondition for the wide application of deuterium/tritium neutron source. At present, there are mature deuterium/tritium titanium targets in scientific or engineering applications abroad, and the neutron yield generally reaches the level of 1013/s. However, the technology of large-area target film in China is immature. The scientific and industrial application of large-area target film is rarely reported. The main problem is that the deuterium/tritium target can not reach the high yield, and the large area of the target film prepared is uneven, the binding force is poor and easy to fall off. In this paper, in order to solve the above mentioned problems and optimize the performance of the target film, magnetron sputtering coating and multi-arc ion plating were combined to prepare large-area titanium films with copper or molybdenum substrate and diameter greater than φ500 mm. At the same time, the feasibility of erbium film, scandium film and zirconium film preparation was explored by preparing large area deuterium-titanium or tritium-titanium targets with high binding force and high deuterium-tritium-titanium ratio. Deuterium and tritium targets with deuterium/tritium titanium ratio greater than 1.85 are produced by using self-developed deuterium/tritium target production system after degassing, purification, high temperature deuterium absorption, tail gas recovery and other processes. In order to better utilize the functions of each film layer, scanning electron microscopy was used to observe the cross-section of the film layer in the experiment. The results show that the clear interface is observed among the base layer, transition layer, and functional layer. The prepared titanium film was tested for neutron yield using a deuterium ion accelerator, and the effects of deuterium ion beam current and anode voltage on neutron yield were analyzed. The experiment shows that with the increase of deuterium beam current, neutron yield shows a linear increase in the range of 700 μA. The effect of anode acceleration voltage on neutron yield increases exponentially in a quadratic relationship. The neutron yield of the developed deuterium target is more than 8.0×108/s, and the neutron yield of the tritium target is estimated according to the reaction section of the deuterium target and the tritium target. Under the same conditions, the neutron yield of the tritium target is more than 1.0×1011/s. The test results show that the developed φ500 mm large area deuterium/tritium target can achieve the high-yield neutron output of the high-current neutron source, reaching the highest neutron flux of 1013/s in the world.

Objective: To improve the film heating process. Methods: In this experiment, edible protein-polysaccharide films were prepared by using the method of chain dissociation at 35, 40, 45, 50, 55 ℃ at one stage and denaturing and heating whey protein isolation at 85 ℃ at the second stage. The structure, hydrophobicity, barrier properties and mechanical properties of the films were compared, and the optimum film forming process conditions were determined. Results: The oxygen resistance, tensile strength （TS） and elongation at break （EAB） of the film increased by 25.0%~58.7%, 54.8%~89.9% and 40.2%~59.2%, respectively, when the film was heated at 25 ℃ and 85 ℃ respectively. Water vapor barrier performance improved by 20.0%~52.6%. The infrared map of the film shows that temperature does not cause the change of the valence bond of the film. It was found that 45 ℃/85 ℃ two-stage step heating process had the most significant effect on improving the properties of the film. Conclusion: After the process optimization, the film's barrier properties and mechanical properties have been improved, which has the potential for food packaging applications.

Objective·To investigate the effect of ceria nanoparticles-polyethylene glycol (CeNP-PEG) on scavenging reactive oxygen species (ROS) and alleviating disease activity in dextran sulphate sodium (DSS)-induced colitis mice.Methods·CeNP was synthesized with the hydrates of cerium acetate, oleamine, and xylene, which was modified with polyethylene glycol-stearyl phosphatidylethanolamine (mPEG-DPSE) to obtain CeNP-PEG. Then CeNP-PEG was purified. The particle size and zeta potential of CeNP-PEG were measured by using transmission electron microscopy (TEM) and dynamic light scattering (DLS). Mouse macrophages (Raw264.7) were cultured in vitro and induced to a pro-inflammatory phenotype (M1 phenotype). M1 macrophages were treated with 0.5 µg/mL and 1.0 µg/mL CeNP-PEG, respectively, and then Western blotting was used to detect the expression changes of the proteins related with nuclear factor-κB (NF-κB) signaling pathway. DSS-induced colitis mice models were constructed, and CeNP-PEG (1.0 mg/mL) was intravenously administrated for 3 times via tail vein during the modeling period. Meanwhile, the body weight, fecal characteristics, and frequency of rectal bleeding in mice were monitored in the normal control group (Normal group), the model group (DSS group), and the CeNP-PEG treatment group. The disease activity index (DAI) was calculated to evaluate the intestinal inflammation. The level of ROS in mouse intestinal tissues was detected by dihydroethidine (DHE) staining and the mRNA expression levels of inflammatory cytokines interferon-γ (Ifn-γ), interleukin-6 (Il-6), Il-1β and tumor necrosis factor-α (Tnf-α) were detected by real-time quantitative PCR (RT-qPCR).Results·The hydrated particle size of synthesized CeNP-PEG was (6.96±0.27) nm, and the average zeta potential was (-6.02±1.31) mV. Western blotting results showed that the expression of p-P65 increased in the pro-inflammatory macrophages compared with the control group. The expression of NF-κB inhibitor-α (IκB-α) decreased, and their expressions tended to recover after the intervention of different concentrations of CeNP-PEG. In the DSS-induced colitis models, mice in the CeNP-PEG treatment group lost less weight than those in the DSS group (P=0.000) and had lower DAI scores (P=0.000). The RT-qPCR results of intestinal tissues showed that the mRNA levels of Ifn-γ, Il-1β, Il-6 and Tnf-α in the DSS group were significantly up-regulated compared with those in the Normal group (P=0.000), and all of them significantly decreased in the CeNP-PEG treatment group. The results of DHE staining showed that the fluorescence intensity of intestinal tissues in the DSS group was significantly enhanced than that in the Normal group, and the fluorescence intensity decreased in the CeNP-PEG treatment group.Conclusion·CeNP-PEG can inhibit the expression of intestinal inflammatory factors and the activation of NF-κB-related inflammatory pathway of pro-inflammatory macrophages, eliminate intestinal ROS, improve the intestinal inflammatory microenvironment, and alleviate the disease activity of DSS-induced colitis in mice.

Functional movement disorder (FMD) is a common subtype of functional neurological disorder (FND), mainly manifested as gait abnormality, tremor, dystonia, postural abnormality, and so on. In recent years, researchers have adopted multi⁃ disciplinary team (MDT) to improve the treatment effect of FMD, among which cognitive behavioral therapy (CBT) has been widely used as an effective psychotherapy program. This article reviews the research progress of CBT for FMD in order to provide guidance for clinical treatment.

Abstract Introduction To date, alpha-feto protein (AFP) remains the most widely used serum biomarker for hepatocellular carcinoma (HCC) diagnosis and prognosis. However, its role has become controversial as close to 30% of early stage HCC patients are AFP negative. Different studies on the diagnostic performance of novel AFP-negative HCC biomarkers have shown inconsistent results of sensitivity, specificity, and area under the receiver operating curve (AUROC). Here, we conducted a systematic review and meta-analysis to resolve this inconsistency. Methods Relevant studies were systematically searched from PubMed, Embase, Cochrane library, Scopus, and the China National Knowledge Infrastructure (chkd-cnki) databases up to the 20th October 2022. The Newcastle–Ottawa Scale was used to assess the methodological quality of included studies. Sensitivity, specificity, and area under the curve were pooled using the random effect model. Results Five studies, with a total of 286 patients, were included. Serum Midkine was assessed using enzyme-linked immunosorbent assay (ELISA) in all the studies, at diagnostic thresholds varying from 0.387 to 5.1 ng/ml. The summary estimates for serum Midkine were 76% (95% CI 70–81%) sensitivity, 85% (95% CI 82–87%) specificity, and 91% area under the receiver operating characteristic curve (AUC), while the pooled diagnostic odds ratio (DOR) was 27.64 (95% CI 4.95–154.17). Conclusion Based on these findings, serum Midkine is a very promising diagnostic biomarker for AFP-negative HCC and should be validated further in large cohort studies.

C15H16N4O, monoclinic, P21/c (no. 14), a = 10.3021(8) Å, b = 15.7835(13) Å, c = 8.3052(7) Å, β = 90.894(7)∘ $90.894{\left(7\right)}^{\circ }$ , V = 1350.29(19)

The R programming language that provides a variety of statistical calculation functions is considered to be one of the programming languages most suitable for artificial intelligence.The correctness of the language implementation is a prerequisite for the correctness of the programs developed with such a language.However,there are inevitably many defects in the R programming language.This paper conducts an empirical study on defects in the R programming language and its core packages.By analyzing 7020 issues,we find that:1) Among all the 35 versions involved in these defects,there are the most defects in R 3.1.2,R 3.0.2 and R 3.5.0,and these defects are primarily distributed in a few components such as Documentation,Graphics,Language.2) The components with higher overall defect priority include Startup,Installation and Analyses,and the components with higher overall defect severity include I/O,Installation and Accuracy.There is a significant intermediate correlation between the priority and severity of the defects.3) About 78% of defects could be repaired within one year.4) Semantic faults are the most frequent root cause of defects,in which the “missing feature” and “processing” are more than others.These findings reveal some laws of defects in the R programming language and its core packages.It can assist developers of the R programming language in improving their development quality,assist maintainers of the R programming language in detecting and repairing defects more effectively,and suggest users of the R programming language evade potential risks.

BACKGROUND The development and utilization of shale gas has become an important way to ensure national energy security and achieve global carbon neutrality goals. Shale gas reservoir is the direct target layer of shale gas exploration and development, because its shale nanopore throat system, dominated by organic pores, has the characteristics of integrated source storage, low porosity, low permeability and non-darcy flow. The evaluation of shale reservoir evaluation needs to break through the bondage of traditional inorganic pore evaluation ideas and the bottleneck of nanoscale characterization technology, and adopt higher precision and resolution experimental technology to characterize nanopores and depict organic pores. OBJECTIVES To understand the research progress on characterization technology of nano organic pore structure in shale and explore the evolution mechanism of organic pore formation, its experimental technical bottlenecks and possible solutions. METHODS According to the experimental types and principles, shale nanopore analysis can be divided into two types: physical experiment technology and imaging analysis technology. The former mainly carries out quantitative physical experiment analysis of rock physical properties, while the latter carries out microscopic in-situ observation and image analysis of pore structure. RESULTS Since organic pores were first discovered in the Barnett shale in North America in 2009, significant progress has been made in studying shale characterization techniques and developmental features. (1)Multi-scale and multi-type nanopore characterization techniques were established. Among them, the quantitative microstructure characterization technologies are dominated by mercury-adsorption joint measurement method and pulse attenuation method. Quantitative parameters of shale physical properties and full aperture distribution ranging from 0.35nm to 10000nm and permeability of < 1μD can be accurately obtained. High-resolution microscopy scanning based on field-emission SEM and microscopy-CT forms a multi-scale structure reconstruction technology of nanopore, and thus 2D-3D image information is available. (2)The formation and evolution of organic pores are controlled by organic matter type, rock evolution and other factors. It is necessary to reveal the internal connection between the influencing factors and the physical evolution law of organic matter molecular structure, which is the key to identify the heterogeneity of shale reservoirs. Formation and keeping of organic pores is in the process of decomposition and condensation reaction competition space effect. (3)Previous studies established a series of kerogen and asphalt structure model for the molecular organic pores evolution mechanism, providing the theoretical basis for research on the genetic mechanism and evolution law of organic pores at the molecular level. Transmission electron microscope and atomic force microscope are used to observe molecular space arrangement and microstructure internal form in stereo. These techniques enable the understanding of the mechanisms of organic pore formation and preservation at the nanoscale. CONCLUSIONS In-situ structure imaging and component scanning technology, reservoir description, composition analysis and digital core integration, are developed to the structure and composition, pore permeability and brittle integration dynamic evaluation. A leap from microstructural analysis to macroscopic big data prediction is realized, meeting the needs of efficient exploration and development of shale gas geology and engineering integration.

Cyclic thrombocytopenia (CTP) is a rare hemorrhagic disorder characterized by cutaneous and mucosal bleeding and periodic fluctuations platelet count. The clinical characteristics and treatment response of a patient with CTP were analyzed. The patient is a 30-year-old male with recurrent cutaneous and mucosal bleeding for 5 years. Skin petechiae, oral blood blister, conjunctival hemorrhage, by tracing the history, monitoring changes in blood routine diagnosis of CTP, further testing of reticulocyte platelets and platelet hormone, and periodically promoting bone marrow megakaryocyte with changes of platelet, confirmed that the patient's periodic reduction in bone marrow hematopoiesis, was causing more damage. Periodic changes of reticulocyte, erythropoietin and erythroid hematopoiesis in bone marrow were also observed. The patient had normal Treg levels, no significant telomere length shortening in peripheral blood nucleated cells, and no clear pathogenic gene mutation was found by whole exon gene sequencing. Recombinant human thrombopoietin(rhTPO) treatment shortened the time of thrombocytopenia and increased the minimum platelet value. The average age of onset of CTP was 35 years old, some patients had severe bleeding, and more than half of the patients were misdiagnosed as primary immune thrombocytopenia. At present, the pathogenesis of CTP has not been clarified and there is no effective treatment. The experience of this patient suggests that rhTPO may be effective. This case of CTP complicated with periodic anemia is the first report. The exploration of its pathogenesis provides important information for understanding CTP.

Objective: A high performance liquid chromatography method was established for determination of four artificial sweeteners in syrups, i.e., acesulfame, saccharin sodium, aspartame and advantame. Methods: Acetonitrile was used as mobile phase A, and 0.02 mol/L ammonium dihydrogen phosphate (pH value adjusted to 5.5 by triethylamine) was used as mobile phase B. The gradient elution was conducted, with flow rate at 1.0 mL/min, and the column temperature was at 35 ℃; the detection wavelength was 214 nm, and sample size was 10 μL was loaded on the was Shiseido AQ-C18 column (4.6 mm×250 mm, 5 μm) A total of 45 batches of children's cough syrup samples from 21 manufacturers were determined by the established method. Results: The linear calibration curve of the four kinds of artificial sweeteners were obtained over the range of 2~100 mg/L. The average recoveries of acesulfame, saccharin sodium, aspartame and advantame were 98.65%, 104.09%, 100.96% and 102.30% respectively, with RSDs less than 2% (n=9). The actual sample test results showed that 3 batches of samples were found to be advename, and 2 batches of samples were found to be aspartame and advename. Conclusion: The established method is specific, simple, and reliable, and can be used to monitor the illegal addition of artificial sweeteners in syrups.

With the continuous maturity of blockchain technology,there are more and more blockchain applications for enterprises that can provide a safe,anonymous and non-tamperable transaction environment.Traditional blockchain architecture is faced with problems such as low performance and insufficient scalability.It can neither meet the needs of high concurrency nor the big data application scenarios for enterprise-level applications.In order to better adapt to the more abundant application scenarios and give full paly to the value of blockchain technology,this paper proposes a simple practical byzantine fault tolerance(SBFT)consensus algorithm to improve the efficiency of the consensus phase,and a Task parallel smart contract model is proposed to make full use of the parallelism efficiency of multi-core systems.we have improved the traditional blockchain system architecture to have the characteristics of light weight,low coupling,and smart contract scalability,which facilitates the secondary development of enterprise applications.On this basis,the ParaChain blockchain and smart contract system are developed.Experimental results show that the performance and scalability of the ParaChain blockchain based on parallelization technology is greatly improved compared to the blockchain system based on the traditional PBFT consensus protocol.

To solve the problems of low level of digitalization of orchard management and relatively single construction method, a three-dimensional virtual orchard construction method based on laser point cloud was proposed in this research. First, the hand-held 3D point cloud acquistion equipment (3D-BOX) combined with the lidar odometry and mapping (SLAM-LOAM) algorithm was used to complete the acquisition of the point cloud data set of orchard; then the outliers and noise points of the point cloud data were removed by using the statistical filtering algorithm, which was based on the K-neighbor distance statistical method. To achieve this, a distance threshold model for removing noise points was established. When a discrete point exceeded, it would be marked as an outlier, and the point was separated from the point cloud dataset to achieve the effect of discrete point filtering. The VoxelGrid filter was used for down sampling, the cloth simulation filtering (CSF) cloth simulation algorithm was used to calculate the distance between the cloth grid points and the corresponding laser point cloud, and the distinction between ground points and non-ground points was achieved by dividing the distance threshold, and when combined with the density-based spatial clustering of applications with noise (DBSCAN) clustering algorithm, ground removal and cluster segmentation of orchard were realized; finally, the Unity3D engine was used to build a virtual orchard roaming scene, and convert the real-time GPS data of the operating equipment from the WGS-84 coordinate system to the Gauss projection plane coordinate system through Gaussian projection forward calculation. The real-time trajectory of the equipment was displayed through the LineRenderer, which realized the visual display of the motion trajectory control and operation trajectory of the working machine. In order to verify the effectiveness of the virtual orchard construction method, the test of orchard construction method was carried out in the Begonia fruit and the mango orchard. The results showed that the proposed point cloud data processing method could achieve the accuracy of cluster segmentation of Begonia fruit trees and mango trees 95.3% and 98.2%, respectively. Compared with the row spacing and plant spacing of fruit trees in the actual mango orchard, the average inter-row error of the virtual mango orchard was about 3.5%, and the average inter-plant error was about 6.6%. And compared the virtual orchard constructed by Unity3D with the actual orchard, the proposed method can effectively reproduce the actual three-dimensional situation of the orchard, and obtain a better visualization effect, which provides a technical solution for the digital modeling and management of the orchard.

Objective To screen and establish a spontaneously high organotrophic cell subline of metastatic breast cancer and to validate characteristic and the organotropism of the lung metastasis cell subline obtained from the screening. Methods By using the experimental lung metastasis, mouse breast cancer cells line 4T07 were injected into tail vein of mouse. Retrieving metastatic tumor cells in the lung and enriching them in vitro; By using the spontaneous metastasis model, the mammary fat pad was inoculated with tumor cells. Combined with the in vitro expansion culture of lung metastasis and repeated three times, a lung organotrophic cell sub-line and model of spontaneous lung metastasis were obtained; A highly metastatic cell subline stably expressing luciferase was obtained by transfection and screening. Cell morphology was microscopied with HE staining and an in vivo imaging system was performed to detect the migration and lung-specific metastasis. Flow cytometry was used to analyze the changes of immune cells in primary site, metastasis and spleen. Wound healing and Transwell assays were performed to detect migration of cell lines in vitro. Results A mouse breast cancer lung-specific metastatic cell subline (4T07LuM) was successfully established. in vivo imaging results validated that the fluorescent signal was mainly concentrated in the lung after injection of 4T07LuM cells labeled with luciferase in situ. HE staining microscopy results verified tumor metastasis in the lung. In addition, according to the results of Transwell and wound healing assays, 4T07LuM, compared to the parental cells 4T07, had shown a significantly more invasive migration(P＜0.001). Finally, according to the results of flow cytometry detection, 4T07LuM cell had showed significantly altered the immune cell ratios as compared to that of 4T07 cell. The immune microenvironment in vivo was more inclined to an immuno-suppressed state. Conclusions Cell sublines with high organ-specific metastasis ability are obtained through combination of serial screening of experimental and spontaneous metastasis and in vitro culture expansion.

Acute myocardial infarction is one of the leading causes of morbidity worldwide, but the underlying mechanism responsible for myocardial ischemia–reperfusion (I/R) injury remains elusive. lncRNA plays roles in inflammatory response, cell apoptosis and regulation of myocardial ischemia. However, whether lncRNA HAGLR could regulate myocardial I/R injury and the molecular mechanism need to be further investigated. lncRNA has been shown to bind to miRNAs and compete with endogenous RNAs. miR-133a-3p has been shown to regulate cardiomyocyte apoptosis and ischemic myocardial injury. In this work, it has shown that knockdown of HAGLR could suppress inflammatory response and cell apoptosis induced by I/R and, thus, alleviate myocardial I/R injury. HAGLR promoted myocardial I/R injury by inhibiting miR-133a-3p to promote MAPK1 expression.

Integrated photonic circuits are created as a stable and small form factor analogue of fiber-based optical systems, from wavelength-division multiplication transceivers to more recent mode-division multiplexing components. Silicon nanowire waveguides guide the light in a way that single and few mode fibers define the direction of signal flow. Beyond communication tasks, on-chip cascaded interferometers and photonic meshes are also sought for optical computing and advanced signal processing technology. Here we review an alternative way of defining the light flow in the integrated photonic platform, using arrays of subwavelength meta-atoms or metalines for guiding the diffraction and interference of light. The integrated metasurface system mimics free-space optics, where on-chip analogues of basic optical components are developed with foundry compatible geometry, such as low-loss lens, spatial-light modulator, and other wavefront shapers. We discuss the role of metasurface in integrated photonic signal processing systems, introduce the design principles of such metasurface systems for low loss compact mode conversion, mathematical operation, diffractive optical systems for hyperspectral imaging, and tuning schemes of metasurface systems. Then we perceive reconfigurability schemes for metasurface framework, toward optical neural networks and analog photonic accelerators.

Extracting uranium from seawater is an important guarantee for the sustainable development of nuclear energy. Rapid uranium extraction material has short adsorption cycle, which can reduce biofouling and aging to give long service life. Therefore, optimizing adsorption cycle can obtain higher uranium extraction efficiency and economic benefits. Herein, a conjugated mesoporous polymer(CMPAO) was developed for monitorable rapid uranium extraction from seawater using aggregationinduced emissionactive triphenylamine and amidoxime modified fluorene moieties. Uranyl ions can be captured by amidoxime group to enhance the electrochemiluminescence(ECL) signal of CMPAO via resonance energy transfer mechanism, which can be applied in uranyl adsorption monitoring to improve adsorption process. The adsorption of CMPAO in uranyl solution(5×10-5 mol/L) can reach equilibrium within 20 minutes with a capacity of 1825 mg/g. In real seawater, the adsorption process can be completed in 3 days, and the adsorption capacity for U reaches 16 mg/g. As the uranium adsorption increases, the ECL signal can be enhanced gradually, which can be employed in monitoring the adsorption process rapidly.

Objective To test the function and evaluate the safety of the self-developed biosafety cage changing workbench. Methods According to the criteria of YY 0569-2011 "Class II Biological Safety Cabinet" and RB/T 199-2015 "Laboratory Equipment Biosafety Performance Evaluation Technical Specifications", we detected the various performance indicators of the cage changing workbench (HT-1303), which was independently developed and produced by Shenzhen Hongteng Biological Technology Co., LTD, and evaluated the safety and validity. Results The appearance integrity and stability of the main body of the biosafety cage changing workbench, the cleanliness of the working area, the velocity of the inflow airflow, the velocity of the descending airflow, the illuminance, the noise level, the airflow direction, the high-efficiency particulate air filter were at good condition, reaching the standards of level II biological safety cabinet. The airtightness of the contaminated goods recovery cabin and the sterilization chamber of utensil surface was good, but the size and quantity of the sterilized cage box need to be further improved. Conclusion The biosafety cage changing workbench developed by our team can be operated properly in whole. It can complete the replacement of individually ventilated cages in this workbench under negative pressure environment. Our workbench also can ensure the safety of operators, environment and experimental subjects.

ObjectiveTo detect the performance and use of class II biosafety cabinets in laboratories of veterinary-related research institutes.MethodsA total of 126 class II biological safety cabinetries being used by three veterinary-related reseatch institutes in Harbin were tested. The performance indicators were judged according to the test results and and analyze according to relevant standards, in order to understand the use of biological safety cabinets.ResultsThe overall pass rate of 126 biosafety cabinetries was 17.5%. The total qualified rate were 100%, 100%, 100%, 100%, 49.2%, 92.9%, 68.3%, 22.2% and 100% ,respectively in terms of the appearance of integrity, cleanliness of work area, integrity of high efficiency filter for supply and exhaust air, flow pattern, the velocity of inflow, the velocity of the downdraft, noise, illumination and alarm and interlock system of class II biosafety cabinet.ConclusionThe overall pass rate of biosafety cabinetries in some veterinary-related research institutes is low. Regular inspection, operation and maintenance management should be strengthened to eliminate biological safety hazard timely and prevent infection accidents of laboratory.

Attribute reduction is a hot research issue in rough set.In this paper, how to reduce redundant attributes without increasing the misclassification cost is studied.Firstly, the minimum misclassification degree of variable precision fuzzy rough sets is defined.Then, by introducing the decision process, the variable precision fuzzy rough set model is proposed based on the minimum misclassification degree.Then, a heuristic attribute reduction algorithm is proposed by taking the misclassification cost as an invariant.We compare this algorithm with other algorithms through experiments.The results show that the attribute reduction results obtained by the proposed algorithm have the advantages of less reserved attributes and lower misclassification cost.

Model tests were performed with different temperatures and soil stabilizers to investigate the effect of horizontal frost heave force on open tunnels in seasonal frozen regions. Experimental results show that the dissipation of the frost heave force accelerated with the increase in temperature, and the data indicate that compared with soil without stabilizers, the horizontal frost heave force decreased by 10% and 15% in soil with lignin fiber and Huaxia No. 1 soil stabilizer. It can be concluded that the inhibitory effect of Huaxia No. 1 soil stabilizer on frost heave force was more significant than that of lignin fiber. According to the test results, the relation expression between horizontal frost heave force and frost heave amount was fitted.

In order to reveal the fracture development and damage evolution law of marble under the influence of temperature, the deformation and failure characteristics and acoustic emission activity of marble under the conditions of 30, 60, 90, 120 ℃ and 150 ℃ were studied by using triaxial servo testing machine and acoustic emission testing system. The results show that the triaxial compression failure of marble under high temperature goes through four stages: compaction and elastic deformation stage, plastic deformation stage, ductile failure stage and instability failure stage. The higher the test temperature is, the longer the compaction deformation stage and ductile failure stage are, and the rock gradually transforms from elastic brittle failure to elastic-plastic failure. The peak strength, elastic modulus and internal friction angle of marble decrease with the increase of temperature. The acoustic emission activity of rock and the correspondence between AE location and macroscopic crack decrease with the increase of test temperature. By analyzing the characteristics of acoustic emission signal amplitude, impact, ring down count, acoustic emission energy, peak frequency and b value in the damage evolution process of marble, it is found that the amplitude fluctuation of acoustic emission is small and the temperature sensitivity is poor, but the peak frequency and b value parameters can better characterize the crack development inside the rock. The peak frequency has the highest temperature sensitivity, which is favorable as the prediction index of rock failure and instability. In the process of triaxial compression failure, tension-shear composite cracks appear in marble, of which shear cracks are dominant. High temperature inhibits the initiation of internal cracks in rock mass. The higher the test temperature is, the weaker the tensile failure and the stronger the shear failure are. The test results shed light on the study of rock thermal damage mechanism and engineering thermal damage monitoring and prediction.

Global path planning is the key technology of mobile robot outdoor work,and global path planning algorithm is mainly used in geographical scenarios to predict the outdoor environment.In the face of the complex outdoor environment,the robot optimizes the algorithm to improve real-time obstacle avoidance of robot path planning,path smoothness,planning effectiveness,which has become the core content in the research of global path planning algorithm.Depending on the degree of intelligent algorithm,the global path planning algorithm for mobile robot is divided into traditional global path planning algorithm and the bionic intelligent global path planning algorithm.Then,this paper further expounds the current practical multi-objective path planning algorithm,introduces several typical optimizations of each algorithm,and summarizes and analyzes the advantages and disadvantages of the improved algorithm.Finally,this paper discusses the future development trend of global path algorithm,and points out four aspects of future research and development,which are optimizing the performance of the conventional algorithm for path planning,various existing algorithms advantage integration,complex environment dynamic obstacle avoidance and improving map representation methods adapting to diverse environment.

Objective: This study aimed to evaluate the uncertainty of determination by high performance liquid chromatography （HPLC） for the content of adevantame, a synthetic sweetener illegally added in syrup drugs. Methods: The sample is diluted with solvent, and the content of adevantame in the sample was determined by HPLC. Through the analysis of the factors affecting the uncertainty, such as the preparation of the reference solution, curve fitting, sample weighing, sample volumetric determination and instrument precision, the uncertainty was synthesized of each component, and the extended uncertainty is calculated. Results: The expanded uncertainty is 1.8 μg/mL. The influence factors from large to small was as follows: repeated sample determination, standard curve fitting, standard solution preparation, sample solution preparation. Conclusion: The established uncertainty evaluation method is accurate and reliable, and truly reflects the source and magnitude of uncertainty.

C34H26N4O5Zn, monoclinic, C2/c (no. 15), a = 29.3891(18) Å, b = 10.3260(5) Å, c = 19.9101(11) Å, V = 5783.1(6) Å3, Z = 8, R gt(F) = 0.0334, wR ref(F 2) = 0.0759, T = 199.99(10) K.

C36H26N4O5Co, triclinic, P212121 (no. 19), a = 10.6380(5) Å, b = 10.6639(5) Å, c = 26.5443(15) Å, V = 3011.2(3) Å3, Z = 4, R gt(F) = 0.0330, wR ref(F 2) = 0.0681, T = 200 K.

BackgroundPost-operative heart transplantation patients often require admission to an intensive care unit (ICU). Early prediction of the ICU length of stay (ICU-LOS) of these patients is of great significance and can guide treatment while reducing the mortality rate among patients. However, conventional linear models have tended to perform worse than non-linear models.Materials and MethodsWe collected the clinical data of 365 patients from Wuhan Union Hospital who underwent heart transplantation surgery between April 2017 and August 2020. The patients were randomly divided into training data (N = 256) and test data (N = 109) groups. 84 clinical features were collected for each patient. Features were validated using the Least Absolute Shrinkage and Selection Operator (LASSO) regression’s fivefold cross-validation method. We obtained Shapley Additive explanations (SHAP) values by executing package “shap” to interpret model predictions. Four machine learning models and logistic regression algorithms were developed. The area under the receiver operating characteristic curve (AUC-ROC) was used to compare the prediction performance of different models. Finally, for the convenience of clinicians, an online web-server was established and can be freely accessed via the website https://wuhanunion.shinyapps.io/PredictICUStay/.ResultsIn this study, 365 consecutive patients undergoing heart transplantation surgery for moderate (NYHA grade 3) or severe (NYHA grade 4) heart failure were collected in Wuhan Union Hospital from 2017 to 2020. The median age of the recipient patients was 47.2 years, while the median age of the donors was 35.58 years. 330 (90.4%) of the donor patients were men, and the average surgery duration was 260.06 min. Among this cohort, 47 (12.9%) had renal complications, 25 (6.8%) had hepatic complications, 11 (3%) had undergone chest re-exploration and 19 (5.2%) had undergone extracorporeal membrane oxygenation (ECMO). The following six important clinical features were selected using LASSO regression, and according to the result of SHAP, the rank of importance was (1) the use of extracorporeal membrane oxygenation (ECMO); (2) donor age; (3) the use of an intra-aortic balloon pump (IABP); (4) length of surgery; (5) high creatinine (Cr); and (6) the use of continuous renal replacement therapy (CRRT). The eXtreme Gradient Boosting (XGBoost) algorithm presented significantly better predictive performance (AUC-ROC = 0.88) than other models [Accuracy: 0.87; sensitivity: 0.98; specificity: 0.51; positive predictive value (PPV): 0.86; negative predictive value (NPV): 0.93].ConclusionUsing the XGBoost classifier with heart transplantation patients can provide an accurate prediction of ICU-LOS, which will not only improve the accuracy of clinical decision-making but also contribute to the allocation and management of medical resources; it is also a real-world example of precision medicine in hospitals.

Microglia is a kind of immune cell in nervous system and has dual regulatory function. It not only streng then phagocytosis, release anti-inflammatory factors to maintain the homeostasis of brain tissues and protect neurons, but also increase the inflammatory response and reduce the scavenging ability of harmful proteins to damage neurons. Under the influence of aging, the expression of CD33 in microglia increased while the expression of TREM2 decreased. In terms of activated phenotype, microglia in the aged population are more inclined to be activated into a pro-inflammatory phenotype, thus promoting the occurrence and progression of AD. In this paper, the mechanisms of microglia inducing and promoting AD were reviewed from the aspects of microglia gene expression, proinflammatory phenotype and immune regulation, in order to provide new strategy for the treatment of AD through microglia.

The continuous maturity of big data, deep learning, intelligent algorithms and other technologies has promoted the third development boom of artificial intelligence. The Chinese government has also promoted the development of artificial intelligence as a national strategy. On the one hand, artificial intelligence technology is gradually penetrating into all aspects of life. For example, through the integration of mobile phone industry and education industry with artificial intelligence, the promotion efficiency of products and services has been greatly improved, and the audience can obtain better service quality. On the other hand, the existing legal system of China cannot solve all the problems of artificial intelligence. The author will attempt to analysis the present situation of artificial intelligence copyright infringement in our country, the protection of different law systems and the prospect of the future about artificial intelligence copyright infringement.

A study involved 48 patients aged 33 to 79 years (average age – 62.6 years) with transient ischaemic attacks (TIA) and visual disorders, caused by cerebrovascular diseases (CVD). 24 patients from this group underwent treatment by GCP criteria and medical care standards in acute brain blood supply disturbances, TIA and therapy with dihydroquercetin “DHQ” “P” drops in the dose of 7 drops, twice a day for 10 days. All the patients had arterial hypertension (AH) stage 1-2. Control group consisted of 26 men and 20 women of comparable age (n=46; average age - 65.9 years) without cerebral ischemic events and visual disorders, findings regarding neurophysiological parameters of visually evoked potentials (VEP) and microcirculatory system state (MCS) were compared. Exclusion criteria: acute heart diseases, type 1-2 diabetes mellitus, glaucoma, secondary types of arterial hypertension and AH stage 3, hemorrhages and hereditary cerebrovascular syndromes. Assessment of the “DHQ” “P” influence on such microcirculatory system parameters (retinopathy components) as perivascular edema, perivascular microhemorrhages, arterio-venular coef­ficient was carried out by results of the fundus oculi vessels computed photometry and biological microscopy of the bulbar conjunctival vessel layers. According to the data regarding distribution of TIA amount, retinopathy stage and age, correlation of TIA was conditioned by retinopathy stage and other factors except of patients’ age. Patients with TIA associated with visual disorders in presence of CVD suffered from arterial hypertension in 72.98%. Stage 1-3 of retinopathy and optic disc functional disorders were all detected. In case of therapy with “DHQ “P” the positive changes in dynamic regarding capillary permeability restoration (in 71.43%±12,07, in retinopathy stage 1-2 in comparison with 38.46% without it) were established and less pronounced – in case of perivascular microhemorrhages. Such positive effects in the conducted study were characterized as tendency pattern (OR 2.87; p=0.08 for perivascular edema and OR 2.77; p=0.08 for microhemorrhages). The efficacy of therapy with “DHQ “P” in restoration of impaired optic disk functions according to the data of VEP (for NO component of VEP; OR 2.87; p=0.041) in the dosage of 7 drops twice a day during 10 days in case of CVD was revealed; this determines the perspective of further investigation of “DHQ “P” which contains dihydroquercetin.

In order to prevent the damage of the connected electronic components at high temperature and improve the wettability of the commonly used low-temperature SnAgCu(SAC) solder on the surface of the base material 25%AlNP/Al(volume fraction) composite and 6061Al alloy, the Ni thin layer or the Ti/Ni bimetal thin layer on the surface of the base metal were pre-metallized by magnetron sputtering, and then connected with a SnAgCu solder, a well-bonded joints was obtained. After double metallization, the interface on both sides of the joint is composed of base material /Ti-Al/Ti/Ti-Ni/Ni/Ni-Sn-Cu/β-Sn+Ag3Sn. The difference in diffusion speed between different elements leads to differences in the phase composition of the interface reaction layer at different positions. From the Ni plating layer to the center of the weld, the phase of the reaction layer is (Ni,Cu)3Sn, (Ni,Cu)3Sn2, (Ni,Cu)6Sn5, (Ni,Cu)3Sn4. The addition of Ti element can significantly improve the bonding strength between the Ni-plated layer and the base metal. The joint shear strength of the joint material obtained by brazing the base metal after double metallization at 250 ℃ for 1 min to 5 min can reach 28-35 MPa, fracture occurs at β-Sn matrix.

Objective To investigate the role of apparent diffusion coefficient (ADC) value in the evaluation of therapeutic effect of radiotherapy for pancreatic cancer. Methods Twenty six patients with pancreatic cancer received radiotherapy were examined with magnetic resonance imaging (MRI) before radiotherapy, one month after radiotherapy, three months after radiotherapy, and six months after radiotherapy,and ADC value of diffusion weighted imaging(DWI) was measured. The patients were divided into remission group and non-remission group according to the change rate before and after radiotherapy, SPSS17.0 software was used to analyze the change of apparent diffusion coefficient before and after radiotherapy and the relationship between the change rates of tumor maximum diameter. Results The ADC value of 26 patients with pancreatic cancer increased significantly after radiotherapy (P＜ 0.001); the ADC value of the remission group was significantly lower than that of the non-remission group before radiotherapy (P＜ 0.05); the ADC value of 26 patients before radiotherapy was negatively correlated with the tumor maximum diameter reduction rate (P＜0.01). Conclusions The change of ADC value before and after radiotherapy is of great value to the radiotherapy for pancreatic cancer, especially to the evaluation of the curative effect when the volume of the focus has not changed significantly. It is also of certain value to predict the degree of volume reduction after radiotherapy and to judge the effect of radiotherapy for pancreatic cancer.

Ni-Ag nanoparticles were prepared by DC arc-discharge plasma method, using the compacted micron-sized powders of Ni and Ag as the raw targets. The content of Ni in Ni-Ag nanoparticles samples was 70.54%(mass fraction). The particles' sizes were mainly in range of 30-70 nm. The results indicate that the resistivity of compressed Ni-Ag powders has low resistivity of 5.36×10-5 Ω·cm. The conductive ink is prepared by using of Ni-Ag nanoparticles (70.54% of Ni) as the additive. An ink line is drew on a polyimide sheet matrix, subsequently dried and sintered at elevated temperatures under protective atmosphere of Ar. The electrical property testing results of sintering samples show dense structure and good conductivity over 300℃. It is indicated that the resistivity of the sintered sample declines with the temperature rising, i.e. 1.83×10-3 Ω·cm at sintering temperature of 450℃ which is much lower than that of the ink line of pure Ni nanoparticles.

Background18F-Flutemetamol (18F-FMM) PET/CT imaging has been widely applied to the diagnosis of mild cognitive impairment and Alzheimer's disease.PurposeThis study aims to explore the distributions of 18F-FMM in different brain regions of mild cognitive impairment (MCI) and Alzheimer's disease (AD) patients and the factors that may affect the combination of 18F-FMM, evaluating the use of 18F-FMM PET/CT imaging in the diagnosis of MCI and AD patients.MethodsFrom July 2020 to April 2021, 24 subjects with MCI (12 males, 12 females, aged of (70.54±9.27) years old), 25 subjects with AD (11 males, 14 females, aged (70.56±7.30) years old) and 9 subjects as normal controls (NC, 2 males, 7 females, aged (57.67±9.00) years old) were recruited from Shanghai. The 18F-FMM PET/CT brain imaging of all subjects were qualitatively and semi-quantitatively analyzed by visual evaluation and standardized uptake value ratio (SUVR), respectively. Student's t-test, one-way analysis of variance and rank sum test were used for the comparison of quantitative variables. Pearson's chi-squared test and Fisher's exact test were used for the comparison of qualitative variables. The diagnostic efficiency was obtained by ROC curve. Multiple linear regression analysis was used to analyze the factors that might affect the combination of 18F-FMM.ResultsThe positive rate of visual assessment was significantly different in NC, MCI and AD groups (χ2=26.85, p < 0.001), and significant differences existed statistically in SUVR of all brain regions among the three groups (H value: 11.54~19.34, F value: 7.43, 11.48, all p < 0.01). The mean values of SUVR in the whole brain of the three groups were statistically different (Z value: -3.87, -2.79, -2.45, all p < 0.016 7). Compared with MCI group, the positive rate in occipital lobe, temporal lobe, parietal lobe and posterior cingulate gyrus was statistically significant (χ2=7.53~10.89, all p < 0.01). With respect to NC, SUVR of all brain regions was lower than that in AD, while SUVR of temporal lobe, frontal lobe and precuneu were lower than that in MCI. Meanwhile, SUVR of occipital lobe, temporal lobe, frontal lobe and parietal lobe in MCI were lower than that in AD. Receiver operating characteristic (ROC) curves showed that the SUVR value of temporal lobe and the mean value of SUVR in the whole brain had the ability to distinguish NC, MCI and AD in sequence. Multiple linear regression analysis showed that cognitive level was significantly negatively correlated with 18F-FMM SUVR in different brain regions.Conclusion18F-FMM PET/CT brain imaging could reflect the cognitive level of middle-aged and elderly people intuitively and has clear diagnostic value for MCI and AD.

C37H36N6O2, monoclinic, P21/c (no. 14), a = 9.18664(12) Å, b = 14.50209(16) Å, c = 23.1787(3) Å, β = 94.0829(12)°, Z = 4, V = 3080.16(7) Å3, Rgt(F) = 0.0398, wRref(F2) = 0.1041, T = 113.5(4) K.

Ni-Ag nanoparticles were prepared by DC arc-discharge plasma method, using the compacted micron-sized powders of Ni and Ag as the raw targets. The content of Ni in Ni-Ag nanoparticles samples was 70.54%(mass fraction). The particles' sizes were mainly in range of 30-70 nm. The results indicate that the resistivity of compressed Ni-Ag powders has low resistivity of 5.36×10-5 Ω·cm. The conductive ink is prepared by using of Ni-Ag nanoparticles (70.54% of Ni) as the additive. An ink line is drew on a polyimide sheet matrix, subsequently dried and sintered at elevated temperatures under protective atmosphere of Ar. The electrical property testing results of sintering samples show dense structure and good conductivity over 300℃. It is indicated that the resistivity of the sintered sample declines with the temperature rising, i.e. 1.83×10-3 Ω·cm at sintering temperature of 450℃ which is much lower than that of the ink line of pure Ni nanoparticles.