Objective To design a search and rescue UAV that is portable and user-friendly in order to meet the needs of rescue personnel on the battlefield.Methods Three-dimensional design software CATIA was used to complete the structural design of the UAV body.In order to make full use of the internal space of the UAV body,folding wings were adopted to reduce the volume of the UAV.By using ABAQUS,the finite elements of the key parts of the UAV were analyzed before the modal analysis of the whole vehicle was conducted to verify the reliability of the structure.The robot simulation software Webots was used for motion simulation of the UAV.Results Simulation analysis and test verification suggested that the structural design of the UAV was well-grounded.It could be quickly and properly deployed by means of hand launch or barrels,which made it easier for rescuers to use the UAV.Conclusion The design and simulation research of UAVs with portable folding wings for search and rescue is of great significance for the research and development of physical prototypes.This study is expected to stimulate new ideas for the development of rescue equipment in the PLA,and contribute to miniaturization of UAVs.

Objective:To develop a robotic digestive endoscope system (RDES) and to evaluate its feasibility, safety and control performance by experiments.Methods:The RDES was designed based on the master-slave control system, which consisted of 3 parts: the integrated endoscope, including a knob and button robotic control system integrated with a gastroscope; the robotic mechanical arm system, including the base and arm, as well as the endoscopic advance-retreat control device (force-feedback function was designed) and the endoscopic axial rotation control device; the control console, including a master manipulator and an image monitor. The operator sit far away from the endoscope and controlled the master manipulator to bend the end of the endoscope and to control advance, retract and rotation of the endoscope. The air supply, water supply, suction, figure fixing and motion scaling switching was realized by pressing buttons on the master manipulator. In the endoscopy experiments performed on live pigs, 5 physicians each were in the beginner and advanced groups. Each operator operated RDES and traditional endoscope (2 weeks interval) to perform porcine gastroscopy 6 times, comparing the examination time. In the experiment of endoscopic circle drawing on the inner wall of the simulated stomach model, each operator in the two groups operated RDES 1∶1 motion scaling, 5∶1 motion scaling and ordinary endoscope to complete endoscopic circle drawing 6 times, comparing the completion time, accuracy (i.e. trajectory deviation) and workload.Results:RDES was operated normally with good force feedback function. All porcine in vivo gastroscopies were successful, without mucosal injury, bleeding or perforation. In beginner and advanced groups, the examination time of both RDES and ordinary endoscopy tended to decrease as the number of operations increased, but the decrease in time was greater for operating RDES than for operating ordinary endoscope (beginner group P=0.033; advanced group P=0.023). In the beginner group, the operators operating RDES with 1∶1 motion scaling or 5∶1 motion scaling to complete endoscopic circle drawing had shorter completion time [1.68 (1.40, 2.17) min, 1.73 (1.47, 2.37) min VS 4.13 (2.27, 5.16) min, H=32.506, P<0.001], better trajectory deviation (0.50±0.11 mm, 0.46±0.11 mm VS 0.82±0.26 mm, F=38.999, P<0.001], and less workload [42.00 (30.00, 50.33) points, 43.33 (35.33, 54.00) points VS 52.67 (48.67, 63.33) points, H=20.056, P<0.001] than operating ordinary endoscope. In the advanced group, the operators operating RDES with 1∶1 or 5∶1 motion scaling to complete endoscopic circle drawing had longer completion time than operating ordinary endoscope [1.72 (1.37, 2.53) min, 1.57 (1.25, 2.58) min VS 1.15 (0.86, 1.58) min, H=13.233, P=0.001], but trajectory deviation [0.47 (0.13, 0.57) mm, 0.44 (0.39, 0.58) mm VS 0.52 (0.42, 0.59) mm, H=3.202, P=0.202] and workload (44.62±21.77 points, 41.24±12.57 points VS 44.71±17.92 points, F=0.369, P=0.693) were not different from those of the ordinary endoscope. Conclusion:The RDES enables remote control, greatly reducing the endoscopists' workload. Additionally, it gives full play to the cooperative motion function of the large and small endoscopic knobs, making the control more flexible. Finally, it increases motion scaling switching function to make the control of endoscope more flexible and more accurate. It is also easy for beginners to learn and master, and can shorten the training period. So it can provide the possibility of remote endoscopic control and fully automated robotic endoscope.

Objective:To assess the applicability of fully automatic pipeline automated testing for internal quality control (automated quality control).Methods:Stability, assay efficiency and implementation costs of 18 biochemical tests, 5 immunoturbidimetric tests and 11 chemical illuminescent tests in the Department of Laboratory Medicine of Peking Union Hospital from January 2019 to July 2022 were evaluated using automated quality control implementation methods. The detailed method is as follows: quality control materials for biochemical, immunoturbidimetric and chemiluminescent tests were stored in the refrigerator in the pipeline which was controlled by the intermediate software, and were automatically retrieved and tested as pre-set followed by documenting and storing. The quality control setup for the biochemical tests included refreshing quality control materials daily and weekly,both of which were paralleled for 3 months. The on-line storage stability of quality control materials in the pipeline was evaluated by comparing the coefficients of variation ( CV) of the quality control results between the two patterns. Effect of automated quality control application was evaluated using 6 indicators, including the results′ variation of automatically performed and manually performed quality controls, the out-of-controlled rate, the consumption of quality control materials, the change of staff workload, the impact on the testing time of the first sample, and the failure rate of automated quality control. Results:(1) Storage stability of quality control materials in the pipeline: under the pattern of weekly refresh of the biochemical quality control materials, except for total carbon dioxide (TCO 2) (the CVs of low and high level quality control were respectively 20.24% and 21.82%) and sodium (the CV of low level quality control was 1.51%) that were greater than the allowable variation set by the laboratory, the CVs of the rest tests meet the lab requirements on the allowable variations. (2) The results′ variation of quality control in automatically performed and manually performed control patterns: in the patterns of daily refresh of biochemical quality control materials and weekly refresh of immunoturbidimetric and chemiluminescent quality control materials, the CVs of both low and high levels of quality control were lower in the automatically performed control pattern than that in manually performed pattern for 8 chemiluminescent items of dehydroepiandrosterone sulfate, estradiol, follicle stimulating hormone, luteinizing hormone, serum ferritin, serum folic acid, vitamin B12 and testosterone, 3 immunologic items of complement 3, C reactive protein and immunoglobulin G, and 10 biochemical items of alkaline phosphatase, glucose, calcium, chloride, potassium, lactate dehydrogenase, sodium, urea, low density lipoprotein cholesterol, and adenosine deaminase. The out-of-control rates of biochemistry, immunoturbidimetric and chemiluminescence tests in both quality control patterns conformed with the clinical routine work requirements. (3) Comparison of quality control materials′ consumption: compared with manually performed quality control, weekly consumption of automatically performed chemiluminescent quality control materials decreased 37.5% (from 8 ml to 5 ml); weekly consumption of automatically performed immunoturbidimetric quality control materials decreased 33.3% (from 3 ml to 2 ml). (4)Comparison of staff workload and first sample testing time: compared with manually performed quality control, automatical quality control reduced manual work by about 156 steps per week, and the daily initial testing time was earlier by 15 min on average. The failure rate was 54.5% (37/64) during the early-stage application of the automated quality control which dropped to 10.2% (13/128) in the late-stage. Conclusion:The results of automated quality control detected in the pipeline system meet the quality indicators′ requirements of the laboratory, and the application of automated quality control can improve the quality control, save costs, reduce workload, and improve work efficiency.

Objective Combination immunotherapy strategies targeting OX40,a co-stimulatory molecule that can enhance antitumor immunity by modulating the proliferation,differentiation,and effector function of tumor-infiltrating T cells,have attracted much attention for their excellent therapeutic effects.In this study,we aimed to evaluate the antitumor efficacy of combined anti-OX40 and hepatitis B core virus-like particles(HBc VLPs)therapy using a mouse colon cancer model. Methods Humanized B-hOX40 mice were injected subcutaneously with MC38 colon tumor cells and treated with HBc VLPs+anti-hOX40 antibody.Tumor growth was monitored.Flow cytometric analysis was performed to evaluate the populations of T cell subsets in the tumors. Results The combination of anti-OX40 with HBc VLPs resulted in a significant delay in tumor growth,suggesting that a potent antitumor immunity was induced by the combination therapy.Further studies revealed that HBc VLPs+anti-OX40 treatment induced a significant increase in effector T cells(Teffs)and a significant decrease in regulatory T cells(Tregs)in the tumor microenvironment(TME),which accounted for the synergistic antitumor effect of anti-OX40 in combination with HBc VLPs. Conclusion Combination therapy of anti-hOX40 and HBc VLPs provides synergistic antitumor activity in colon cancer-bearing mice,which may represent a potential design strategy for cancer immunotherapy.

Objective:To analyze the whole genome sequence and key site mutations of hepatitis B virus (HBV) in patients with different stages of disease progression, and to understand the relationship between HBV genetic characteristics and disease progression.Methods:Serum samples and basic information of hepatitis B patients with asymptomatic HBV carrier, chronic hepatitis B patients, cirrhosis patients and primary hepatocellular carcinoma patients were collected. Nested PCR was used to amplify the samples to obtain HBV whole gene sequences. Phylogenetic trees were constructed to determine the genotype of the samples, and gene mutations of the samples were analyzed combined with reference sequences of each type.Results:A total of 256 samples were successfully amplified, including 68 asymptomatic HBV carrier patients, 118 CHB patients, 15 LC patients and 55 HCC patients, and five genotypes (B, C, D, I and C/D) were detected. The result of comparative analysis showed that the mutation rate of 56 nucleotide sites was significantly different among the four groups ( P<0.05). In addition to the discovery of C105T, A1762T/G1764A and G1899A and other previously reported key site mutations, the mutation rates of T53A, C1485T and C1628T in newly diagnosed HCC group were significantly higher than those in other groups, and the mutation rates of T2150G and T2151C in asymptomatic HBV infection group were significantly higher than those in other groups. A total of 26 sequences were deleted, mainly distributed in the pre-C and pre-S regions. The deletion mutation rate in the HCC group was significantly higher than that in the other groups. Conclusions:The data of this study indicate that some nucleotide substitution mutations and deletion mutations may be closely related to the occurrence and development of HBV-related diseases, and HCC patients are more likely to have gene mutations than non-HCC patients. These result provide a reference for understanding the relationship between viral mutation and the progression of HBV infection-related diseases.

Objective To evaluate the therapeutic effect of Huangqin Decoction(HQD)on ulcerative colitis(UC)in mice and explore its mechanism.Methods Male Balb/c mice were randomly divided into normal control group,model group,mesalazine group(5-ASA,200 mg/kg),and low-,medium-and high-dose HQD groups(2.275,4.55 and 9.1 g/kg,respectively).With the exception of those in the normal control group,all the mice were exposed to 3%DSS solution in drinking water for 7 days to establish UC models.After treatment with the indicated drugs,the mice were assessed for colon injury and apoptosis using HE,AB-PAS and TUNEL staining,and the expression levels of inflammatory factors were detected with ELISA.Western blotting,immunohistochemistry and qRT-PCR were used to detect the changes in protein expressions associated with the intestinal chemical barrier,mechanical barrier and endoplasmic reticulum stress(ERS).Results HQD treatment significantly reduced DAI score and macro score of UC mice,decreased colonic epithelial cell apoptosis,lowered expressions of IL-6,TNF-α,IL-1β and IL-8,and enhanced the expressions of MUC2 and TFF3.HQD treatment also upregulated the protein expressions of claudin-1,occludin and E-cadherin,reduced the expressions of GRP78,CHOP,caspase-12 and caspase-3,decreased the phosphorylation levels of PERK,eIF2α and IRE1α,and increased the Bcl-2/Bax ratio in the colon tissues of UC mice.Conclusion HQD inhibits colonic epithelial cell apoptosis and improves intestinal barrier function in UC mice possibly by reducing ERS mediated by the PERK and IRE1α signaling pathways.

Purpose::Under-foot impact loadings can cause serious lower limb injuries in many activities, such as automobile collisions and underbody explosions to military vehicles. The present study aims to compare the biomechanical responses of the mainstream vehicle occupant dummies with the human body lower limb model and analyze their robustness and applicability for assessing lower limb injury risk in underfoot impact loading environments.Methods::The Hybrid III model, the test device for human occupant restraint (THOR) model, and a hybrid human body model with the human active lower limb model were adopted for under-foot impact analysis regarding different impact velocities and initial lower limb postures.Results::The results show that the 2 dummy models have larger peak tibial axial force and higher sensitivity to the impact velocities and initial postures than the human lower limb model. In particular, the Hybrid III dummy model presented extremely larger peak tibial axial forces than the human lower limb model. In the case of minimal difference in tibial axial force, Hybrid III's tibial axial force (7.5 KN) is still 312.5% that of human active lower limb's (2.4 KN). Even with closer peak tibial axial force values, the biomechanical response curve shapes of the THOR model show significant differences from the human lower limb model.Conclusion::Based on the present results, the Hybrid III dummy cannot be used to evaluate the lower limb injury risk in under-foot loading environments. In contrast, potential improvement in ankle biofidelity and related soft tissues of the THOR dummy can be implemented in the future for better applicability.

Objective To observe the value of hemagglutinin occlusion of needle passage for preventing complications of pulmonary puncture biopsy.Methods Data of 155 patients with single pulmonary nodule who underwent CT-guided percutaneous lung puncture biopsy were retrospectively analyzed.The patients were divided into observation group(n=78,injected hemagglutinin when withdrawing the needle)and control group(n=77,directly withdrawn the needle).Chest CT examination was performed immediately after completion of the procedure.Pulmonary hemorrhage grades were evaluated,and the proportions of compressed lung area were measured and compared between groups.Results Puncture and sampling were successfully performed in all 155 patients,and definite pathological diagnose was acquired in 150 cases(150/155,96.77%).High-grade hemorrhage was detected in 20 cases(20/78,25.64%)of observation group and 38 cases(38/77,49.35%)of control group,while pneumothorax was noticed in 18 cases(18/78,23.08%)with lung compression area proportion of(0[0,0])in observation group,and in 31 cases(31/77,40.26%)with lung compression area proportion of 0[0,0.76%]in control group,respectively,in observation group were better than in control group(all P＜0.05).Conclusion Occlusion needle passage when withdrawing needle with hemagglutinin after pulmonary puncture biopsy could reduce the risk of hemorrhage and pneumothorax.

Endodontic diseases are a kind of chronic infectious oral disease.Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha.However,it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT).Recent research,encompassing bacterial etiology and advanced imaging techniques,contributes to our understanding of the root canal system's anatomy intricacies and the technique sensitivity of RCT.Success in RCT hinges on factors like patients,infection severity,root canal anatomy,and treatment techniques.Therefore,improving disease management is a key issue to combat endodontic diseases and cure periapical lesions.The clinical difficulty assessment system of RCT is established based on patient conditions,tooth conditions,root canal configuration,and root canal needing retreatment,and emphasizes pre-treatment risk assessment for optimal outcomes.The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT.These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics.

Objective To investigate the predictive value of systemic immune inflammation index(SII)scores in long-term survival of patients with stage Ⅲ squamous lung cancer treated with radical radiotherapy.Methods Clinical data of stage Ⅲ squamous lung cancer patients who underwent radical radiotherapy at the Radiotherapy Department of the Fourth Hospital of Hebei Medical University from January 2010 to December 2018 were retrospectively analyzed.The peripheral hematological indexes one week before radiotherapy were collected and recorded.X-Tile software was applied to determine the best cut-off values for continuous variables.Kaplan-Meier method was used to analyze overall survival(OS)and progression-free survival(PFS).Results A total of 453 patients were included in this study.There were 336 patients in the low SII group(＜1 277.3),and other 117 patients were in the high SII group(≥1 277.3).The median OS and median PFS in the high SII group were shorter than those in the low SII group(OS:20.8 months vs.31.0 months,Log-rank χ2=18.015,P＜0.01;PFS:13.0 months vs.21.0 months,Log-rank χ2=15.062,P＜0.01).Multivariate Cox regression analysis showed that high SII was associated with OS(HR=1.628,95%CI:1.294-2.047,P<0.001)and PFS(HR=1.559,95%CI:1.240-1.961,P<0.001).Other influencing factors included late TNM stage,poor radiotherapy efficacy and decreased HALP score.Conclusion SII can be used to evaluate the long-term survival of patients with stage Ⅲ lung squamous cell carcinoma receiving radical radiotherapy,and the increase of SII indicates a poor prognosis.