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.

BACKGROUND:Calcium phosphate(CaP)coatings are widely used to improve the integration of titanium implants into bone but these coatings are associated with risks of infection.It is thus desirable to confer antibacterial properties to CaP coatings. OBJECTIVE:To prepare CaP-MgO composite coatings by impregnating magnesium oxide(MgO)sol into CaP coatings and assess the in vitro antibacterial activities and cytocompatibility. METHODS:An electrolyte was determined by titration and used for CaP coating electrodeposition on titanium(referred to as Ti-CaP).MgO was impregnated into the coating by immersing in an MgO sol with different mass fractions(15%,30%,50%)and subsequently calcined to form MgO-CaP composite coatings,which were recorded as Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg,respectively.Microstructure,tensile properties,critical load,and Mg2+ release of coatings in vitro were characterized.Antibacterial activity was assayed using spread plate method by culturing S.aureus on the pure titanium sheet surface and Ti-CaP,Ti-Cap-15mg,Ti-Cap-30mg and Ti-Cap-50mg surfaces for 24 and 48 hours.Mouse osteoblast suspension was inoculated on pure titanium sheets and Ti-CaP,Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg coated titanium sheets,respectively.Cell proliferation was detected by CCK-8 assay,and cell survival rate was calculated.The morphology of composite coating soaked in DMEM was also observed. RESULTS AND CONCLUSION:(1)Homogeneous,microporous CaP coatings consisting of octacaclium phosphate crystal flakes were prepared on titanium by electrodeposition.After sol impregnation-calcination,MgO aggregates were filled into the inter-flake voids.The extent of MgO filling and Mg concentration in the coating increased with the number of sol impregnation procedures.When immersed in phosphate buffered saline,all composite coatings actively released Mg2+ within 1 day;subsequently,the Mg2+ release slowed down on day 3.A small amount of Mg2+ release was still detected on day 7.The yield strength,tensile strength and fracture growth rate of Ti-CaP-30Mg coated titanium were not significantly different from those of pure titanium(P>0.05).There was no significant difference in the critical load of Ti-CaP,Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg groups(P>0.05).(2)Except that pure titanium sheet and Ti-CaP had no antibacterial properties,the other samples had good antibacterial properties,and the antibacterial rate increased with the increase of MgO content in the coating.(3)After 1 and 3 days of co-culture,the cell survival rate of Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg groups was lower than that of pure titanium group and Ti-CaP group(P<0.05).After 5 and 7 days of culture,there was no significant difference in cell survival rate among five groups(P>0.05).The content of MgO in the coating decreased gradually with the time of immersion in the medium.(4)The MgO sol impregnation added antibacterial properties to the CaP coatings while retained their biocompatibility.

Objective:To explore the method of obtaining the key parameters of the average value articulator in healthy people based on mandibular movement trajectory data, with a view to providing a reference for the clinical application of the average value articulator.Methods:One hundred healthy volunteers (42 males and 58 females) with individual normal occlusion, aged 18-55 years old, who met the inclusion criteria were recruited from Beijing, and their mandibular movement trajectory data were collected. The left and right sagittal condylar inclination(SCI) and transversal condylar inclination(TCI) were obtained from the values of the articulator parameters which were generated in the mandibular movement analysis system.The SCI and TCI were grouped by gender and calculated separately for the two groups and the overall sample; the gender differences in the two parameters and the differences between the mean values of the two parameters and the average value articulator empirical values (35° for SCI and 15° for TCI) for the overall sample were compared.Results:The differences between SCI (35.8°±7.4°) and TCI [11.2° (11.3°)] in males and the corresponding parameters [35.6°±8.3° and 10.8° (9.5°), respectively] in females were not statistically significant ( t=0.10, P=0.922; Z=-0.60, P=0.552); the overall sample SCI (35.7°±7.9°) did not differ statistically from the average value articulator empirical value ( t=1.23, P=0.221), and the overall sample TCI [10.9° (10.3°)] was significantly smaller than the average value articulator empirical value ( W=5 825.00, P<0.001). Conclusions:The mandibular movement trajectory data of 100 adults with individual normal occlusion in this study shows that the gender factor does not affect the setting of the key parameters of the average value articulator, the SCI of the average value articulator empirical values is appropriate, and the TCI has the possibility of being on the large side. In the clinical use of the articulator to assist in the design of restorations, the parameter values should be rationally adjusted according to the actual situation of the patient′s dentition and mandibular movement.

Objective To investigate the dietary patterns of rural residents in the high-incidence areas of esophageal cancer (EC), and to explore the clustering and influencing factors of risk factors associated with high-incidence characteristics. Methods A special structured questionnaire was applied to conduct a face-to-face survey on the dietary patterns of rural residents in Yanting county of Sichuan Province from July to August 2021. Univariate and multivariate logistic regression models were used to analyze the influencing factors of risk factor clustering for EC. Results There were 838 valid questionnaires in this study. A total of 90.8% of rural residents used clean water such as tap water. In the past one year, the people who ate fruits and vegetables, soybean products, onions and garlic in high frequency accounted for 69.5%, 32.8% and 74.5%, respectively; the people who ate kimchi, pickled vegetables, sauerkraut, barbecue, hot food and mildew food in low frequency accounted for 59.2%, 79.6%, 68.2%, 90.3%, 80.9% and 90.3%, respectively. The clustering of risk factors for EC was found in 73.3% of residents, and the aggregation of two risk factors was the most common mode (28.2%), among which tumor history and preserved food was the main clustering pattern (4.6%). The logistic regression model revealed that the gender, age, marital status and occupation were independent influencing factors for the risk factors clustering of EC (P<0.05). Conclusion A majority of rural residents in high-incidence areas of EC in Yanting county have good eating habits, but the clustering of some risk factors is still at a high level. Gender, age, marital status, and occupation are influencing factors of the risk factors clustering of EC.

Objective To explore the biomechanical responses of the cupula of the human semicircular canal to three basic rotational perception processes.Methods A one-dimensional visual semicircular canal model was successfully fabricated using three-dimensional printing and hydrogel physical cross-linking technologies,and the response deformation of the cupula was explored by applying constant angular velocity,constant angular acceleration,and sinusoidal oscillation stimulations.Results The time constant of the biomimetic semicircular canal model was stable at approximately 3 s and close to the human time constant.The displacement deformation of the ampullary cupula was proportional to the angular acceleration applied.Under sinusoidal oscillation stimulation of 0.07-5.00 Hz,the gain of the semicircular canal increased from 1.54 um/° rises to 42.34 μm/°,but the phase difference decreased from 109.72° to 11.27°.Conclusions The biomimetic semicircular canal model prepared in this study can accurately simulate the working mechanism of the human semicircular canal and is expected to play a role in mechanism research and disease diagnosis of the human vestibular semicircular canal.

Objective:To evaluate the efficacy of first-line tyrosine kinase inhibitors (TKI) plus immune checkpoint inhibitors (ICI) in metastatic fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC).Methods:The data of 87 metastatic FH-deficient RCC patients from West China Hospital ( n=44), Renji Hospital ( n=27) and Sun Yat-sen University Cancer Center (n=16) from Mar 2019 to Aug 2022 were retrospectively analyzed. The median age was 37(30, 47) years, the male to female ratio was 1.9∶1. The median size of tumor was 7.5(5.0, 10.0) cm. Sixty-one patients (70.1%) had germline FH mutations, and 26 patients (29.9%) had somatic FH mutations. Forty-nine patients (56.3%) metastasis disease at initial diagnosis, and 38 patients (43.7%) had metachronous metastasis. The most common site of metastasis was lymph node (41/87, 47.1%), followed by bone (33/87, 37.9%), liver (22/87, 25.3%), and lung (14/87, 16.1%). Fifteen patients (17.2%) had weak expression of FH protein and 59 patients (67.8%) had positive PD-L1 expression. The most common treatments were sintilimab plus axitinib (52/87, 59.8%), followed by pembrolizumab plus cabozantinib (7/87, 8.0%), tirelizumab plus axitinib (6/87, 6.9%), pembrolizumab plus axitinib (5/87, 5.7%), and toripalimab plus axitinib (4/87, 4.6%). Thirteen patients (13/87, 14.9%) received other ICI plus TKI combination treatments. Statistical analysis was conducted using R 4.2.3 software. Kaplan Meier survival curve was used to evaluate survival data, and log-rank test was used to compare differences between treatment groups. Results:The overall objective response rate (ORR) and disease control rate (DCR) of first-line TKI + ICI were 39.1% and 89.7%, respectively. The median progression-free survival (PFS) and overall survival (OS) were 16.5 months and 71.0 months, respectively. For first-line sintilimab plus axitinib, the ORR and DCR were 44.2% and 92.3%, respectively. The median PFS was 17.3 months and the median OS was not reached for this combination treatment. The efficacy of first-line tirelizumab plus axitinib was inferior to other treatment strategies (median PFS: 4.0 vs. 16.6 months, P<0.001; median OS: 22.0 vs. 71.0 months, P=0.043). Subgroup analyses further showed that the efficacy of ICI+ TKI combination therapy was consistent in patients with different clinicopathologic and genomic features. However, patients with liver metastasis had shorter OS than those without liver metastasis (median OS: 26.3 vs. 71.0 months, P=0.021). Conclusion:First-line TKI + ICI is effective for metastatic FH-deficient RCC and can significantly prolong the survival of the patients.

Osteoarthritis is a common degenerative joint disease, and cartilage damage is often considered an early factor in irreversible joint degeneration. Repairing damaged cartilage remains a medical challenge due to its limited ability to self-repair and regenerate. In recent years, the application of tissue engineering strategies to treat cartilage defects has been recognized as an emerging therapeutic avenue. Acellular cartilage matrix (ACM) is an ideal material for cartilage repair and regeneration as it retains the extracellular matrix structure and bioactive components of natural cartilage, mimicking the extracellular environment of natural cartilage to the greatest extent. Type II collagen is the main type of hyaline cartilage and plays an important role in regulating the mechanical properties of cartilage tissue. It has been shown that type II collagen, growth factors and the hypoxic microenvironment play important roles in promoting cartilage regeneration. Type II collagen induces cell aggregation and chondrogenic differentiation in a specific way; Various growth factors contained in the ACM induce Sox9 expression and promote chondrogenic differentiation of stem cells; The hypoxic microenvironment upregulates the expression of type II collagen (COL2A1), Sox9 and maintains chondrocyte phenotype. In addition, ACM has been widely used in cartilage regeneration studies, either as a decellularized scaffold, hydrogel or 3D bioprinting technique for the repair of defective cartilage. Although the ACM-derived biomaterials discussed in this paper have many advantages, there are still some difficulties in their practical applications, such as loss of ACM components and reduced scaffold performance, which are still worth exploring in depth.

Purpose: To evaluated the efficacy and safety of gelatinized Maca (Lepidium meyenii) for eugonadal patients with late onset hypogonadism symptoms (LOH). Materials and Methods: Participants were instructed to receive 1,000 mg of Maca or placebo, two pills at a time, three times per day for 12 weeks before food intake. To evaluate the efficacy of the drug, Aging Males’ Symptoms scale (AMS), Androgen Deficiency in the Aging Males (ADAM), International Prostate Symptom Score (IPSS), and International Index of Erectile Function (IIEF) questionnaires, serologic tests (total testosterone and free testosterone, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglyceride), body weight, and waist circumference were assessed at 4 and 12 weeks after treatment. Results: A total of 80 participants were enrolled and randomly assigned to Maca treated group (n=41) or the placebo group (n=39). AMS, IIEF, and IPSS were significantly (p<0.05) improved in Maca treated group than in the placebo group. ADAM positive rate was also significantly (p<0.0001) decreased in Maca treated group. Conclusions Maca may be considered an effective and safe treatment for eugonadal patients with late onset hypogonadism symptoms.

Objective:To analyze the epidemiological characteristics, high risk factors and pathogenic factors of sepsis-related liver injury patients by collecting epidemiological data and the sequencing results.Methods:A total of 288 sepsis patients been admited to the Emergency Department of the First Affiliated Hospital of Air Force Military Medical University from January 1, 2018 to December 31,2019 were selected and divided into sepsis liver injury group ( n = 44) and sepsis without liver injury group ( n = 244) according to whether acute liver injury occurred or not. The differences ofthe general data, hematological parameters, severity of illness and other indicators at admission between the two groups were compared and analyzed. Logistic regression was used to analyze the risk factors of sepsis-related liver injury. Total of 8 septic patients with liver injury and 4 septic patients without liver injury were selected for RNA-sequencing. Ribonucleic acid (RNA) was extracted from peripheral blood mononuclear cell of patients, detected using RNA-seq, and differential genes were screened and analyzed. Results:Compared with the sepsis without liver injury group, patients in the liver injury group suffered less hypertension (11.4% vs. 30.3%) and relatively more chronic renal insufficiency (40.9% vs. 12.1%); more patients were admitted to the emergency department due to renal disease (43.2% vs. 24.6%), higher sequential organ failure score (SOFA) and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score (SOFA (points) 9.86 ± 3.59 vs. 5.41 ± 3.13, APACHE Ⅱ (points) (16.07 ± 4.41) vs. (14.46 ± 3.77), with prolonged hospital days (d): 8 (4.75, 13.75) vs. 6 (2, 9)]; in the liver injury group, the incidence of infection in respiratory and digestive systems (70.5% vs. 18.0%) andthe chance of infection with Staphylococcus aureus were higher (9.1% vs. 2.0%), and laboratory parameters (procalcitonin (PCT), lactate dehydrogenase (LDH), partial thromboplastin time (APTT), direct bilirubin (DBIL), aspartate aminotransferase (ALT), alanine aminotransferase (AST)) were significantly increased [PCT (μg/L) (23.90 ± 33.22) vs. (10.95 ± 20.18), LDH (U/L) 540.00 (370.50, 1177.00) vs. 168.00 (98.65, 875.18), APTT (s) (41.50 ± 3.13) vs. (36.23 ± 5.27), DBIL (μmol/L) 18.50 (10.10, 58.85) vs. 10.30 (7.60, 16.85), ALT (U/L) 67.00 (41.25, 164.00) vs. 29.00 (18.00, 51.25), AST (U/L), 101.00 (51.25, 174.75) vs. 35.00 (25.00, 65.50)], while platelet (PLT) and albumin (Alb) were significantly lower than those in the sepsis without liver injury group [PLT (× 10 9/L) 62.50 (38.50, 164.25) vs. 90.5 (66.25, 165.5), Alb (g/L) (30.17 ± 7.16) vs. (34.20 ± 6.50)] (all P < 0.05).Logistic regression analysis revealed that Staphylococcus aureus infection, thrombocytopenia, elevated procalcitonin, elevated lactate dehydrogenase, elevated total bilirubin, and elevated glutamyltransferase were associated with sepsis with acute liver injury (odds ratio, OR) with 95% confidence interval (95% CI) of 0.1167 (0.0380~0.7300), 0.9836 (1.0060~1.0290), 0.9986 (1.0000~1.0001), 0.9745 (1.0040~1.0170), 1.0020 (0.9940~1.0000), and 0.9931 (1.0000~1.0001), respectively. A total of 311 significantly differential expressed genes (DEGs) were selected, with 151 up-regulated genes and 160 down-regulated genes compared with the septic non-liver injury group. Further bioinformatics analysis reveled that the top 10 GO sequences are:①platelet α granules,② platelet α granule cavity,③wound healing,④cell migration,⑤multicellular organism process,⑥anatomical structure development,⑦cartilage ossification,⑧tissue development,⑨ keratinization,⑨Multicellular biological development. And KEGG pathway enrichment analysis revealed that human disease-related pathways were dominant, mainly including purine metabolism, AGE-RAGE signaling pathway, p53 signaling pathway, porphyrin and chlorophyll metabolism, nitrogen metabolism, mineral nutrient absorption, protein processing in the endoplasmic reticulum, and FoXo signaling pathway. Conclusions:Staphylococcus aureus infection, thrombocytopenia, elevated procalcitonin, elevated lactate dehydrogenase, elevated total bilirubin, and elevated glutamyltransferase were independent risk factors for sepsis liver injury. Coagulation dysfunction, apoptosis, and metabolic level changes may be important mechanisms of sepsis-associated liver injury, which are related to purine metabolism, porphyrin and chlorophyll metabolism and the expression of genes related to FoXo signaling pathway, Hippo signaling pathway, and p53 signaling pathway.