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With the breakthroughs in artificial intelligence, orthopedic surgical robots have rapidly advanced, presenting good prospects for their applications in the medical field. Prior to the clinical application of this novel medical device, ensuring high reliability is crucial to safeguarding patient safety and surgical quality. Therefore, a thorough understanding of the types of failures and associated risks is essential during both the development and clinical application phases. From the perspectives of both the research and development companies and clinical users, this article comprehensively elucidates the types of failures and their associated risks in orthopedic surgical robots. Furthermore, strategies for addressing high-risk failures are proposed, with the aim of providing guidance for the development and clinical application of orthopedic surgical robot devices, thereby contributing to the high-quality advancement of this field.

BaTiO3 has advantages of high permittivity, low dielectric loss, low cost and environment friendly. However, due to the nonlinear dielectric behavior occurred around the phase transition temperature of BaTiO3 ceramic, its availability in the field of temperature-stable capacitor is limited. To modify the dielectric-temperature properties of BaTiO3, a series of BaTi1-xCexO3 (x=0-0.20) ceramics was synthesized by solid-state reaction method. Ce dopant was introduced into the B-site (Ti-site) of BaTiO3. The effects of Ce dopant on the phase evolution, defect state, microstructure and dielectric properties were investigated. The modifying mechanism was also discussed with the help of first-principles calculation method. In all ceramic samples, it is revealed that Ce element completely enters the B-site of BaTiO3 in the form of Ce4+ ion. With the increase of Ce doping concentration, the room temperature structure of BaTi1-xCexO3 ceramics transforms from tetragonal/pseudo-cubic structure into orthorhombic/tetragonal structure, then into pseudo-cubic structure. Owing to the radius difference between Ce4+ and Ti4+ ions, Ce doping will lead to the rising of lattice parameters, accompanied by the appearance of local distortion and the decrease of long-range ferroelectric order, the variation of band structure, density of states and charge density configuration, as well as the generation of Ba and Ti vacancies. Compared with pure BaTiO3 ceramic, the average grain size of Ce-doped ceramics decreases first and then increases with the increase of Ce content, while the relative density of ceramics increases gradually. The peak dielectric constant of BaTi1-xCexO3 ceramic increases first and then decreases as the Ce concentration increasing. The corresponding temperature is slowly reduced from 122 ℃ to 112 ℃ in the x value range of 0-0.08, then rapidly declines to -3 ℃ in the x value range of 0.08-0.20. BaTi1-xCexO3 ceramics with x≥0.06 have the dielectric behavior of diffused phase transition (DPT). And the x=0.20 ceramic exhibits the typical characteristic of relaxor ferroelectric, with the room temperature dielectric constant of 3258.38, and the |Δεr/εr25 ℃|≤22% temperature range of -60-87 ℃, which matches the requirement of EIA X5S standard. Therefore, it can be concluded that B-site Ce doping will effectively enhance the permittivity stability of BaTiO3 in a variable temperature environment. This will provide some new ideas to develop dielectric materials with stable dielectric properties in wide temperature range.

Owing to the feature of ultrahigh power density, the dielectric capacitors play an increasingly important role in the field of industrial production, basic scientific research, aerospace, and military industry in recent years. However, the relatively low energy storage density of the dielectric capacitors generally leads to their big sizes, which is difficult to meet the miniaturization requirements of future devices. Polymer-ceramic nanocomposites can combine high permittivity of the ceramic fillers and the excellent breakdown strength of the polymer matrix, thus achieving excellent energy storage performance. At present, developing the polymer-ceramic nanocomposites with high energy storage density is the key to realize the miniaturization goal of dielectric capacitors in the future. The current research progress of polymer-ceramic nanocomposites for energy storage capacitor applications from three perspectives was systematically summarized, including regulation of the nanofillers, optimization of the interfaces, and design of the multilayer composite structure. Notably, the influences of the dimension, size, species, hierarchical structure of the nanofillers, interface optimization methods such as surface modification and core-shell structure construction, as well as multilayer structure design such as sandwich structure and gradient structure on the permittivity, breakdown strength and the energy storage density of the nanocomposites were introduced in detail. Meanwhile, the structure-activity relationships between the microstructure of nanocomposites and their energy storage properties were further analyzed and discussed. Finally, based on the challenges and shortcomings of the current research, the important development directions of this field in the future were proposed, including selecting the new 2D nanofillers, enhancing the energy storage efficiency, employing multimode combined optimization strategy, and constructing the corresponding dielectric capacitors.

Objective To analyze the clinical effect of total parathyroidectomy with forearm autotransplantation on secondary hyperparathyroidism. Methods From January 2017 to December 2020, calcium, phosphorus, intact parathyroid hormone, alkaline phosphatase and clinical symptoms of 26 patients who received total parathyroidectomy with forearm autotransplantation in our hospital were studied. The patients with end-stage renal disease in this study had persistent dialysis in the treatment of secondary hyperparathyroidism before admission. Results A total of 105 parathyroid glands of all patients were removed. The symptoms including ostalgia and itch of skin were improved or removed in all cases. Amount of calcium, phosphorus, alkaline phosphatase and intact parathyroid hormone in serum decreased significantly post-operative 3 and 6 months than before (P

The problems with the jigging process were that, the raw coal can't be separated effectively, separation precision and recovery efficiency decreased markedly, the quality of clean coal was unstable and its yield was low. Conducted screen analysis and small size slurry float-and-sink analysis. The results show that, the primary slime content is 7. 30%, the middlings content is 20. 17%, so the raw coal is difficult to separate. Analyze the influence of raw coal size, moisture, gangue content, emissions of elevator on jig working parameters. When the lump coal is less, the separation capacity of jig should be reduced to a minimum, meanwhile, reduce the air volume and emissions, increase the frequency. When the lump coal is large, the water content, horizontal kinematic velocity of bed and middlings discharging should be increased, the air volume should be decreased. When the moisture of raw coal is high, the feeding coal should be increased by 8% to 15%. If the gangue content increased, lowering the height of first-stage bed and increasing the screening efficiency of first--stage lighten the handing capacity of middlings treating process. If the lump coal in bucket type elevator were large, the thickness of second-stage bed should be increased, the discharging and air emission of second-stage should be decreased. If there were larger gangue in bucket type elevator, the feeding coal and the second--stage height of the second--stage should be decreased, gangue discharging and air volume should be increased. [ABSTRACT FROM AUTHOR]

The development of the automotive technology makes the vehicle mobility possible. The current technologies commonly used include active suspension, intelligent differential lock, central tire inflation system, and torque control-based engine technology. These new technologies cannot be applied unless the road character is predicted by the vehicle. Soil support strength "cone index" (CI, pound/inch²) can be classified into 3 categories: 30-75, 75-125, and > 125. Based on the CI classification, the road also can be classified. On the road with CI Category 1, the vehicle usually cannot go through; on the road with CI Category 2, the vehicle can pass through quickly by the soft road pattern; and the road with CI Category 3 can barely affect the mobility of the vehicle. In this study, to identify the soft road, the rolling coefficients threshold based on the experiences was established between Category 1 and Category 2. It assumed that the mobility of the vehicle would be better improved if a vehicle identified the road feature and then adjusted the vehicle-self running at the soft pattern automatically. To increase the mobility of the military off-road vehicle, one identification method of the soft roads based on real-time monitoring of the rolling resistance was put forward. Since the tire barely deformed, it could be regarded as a rigid-body when a vehicle was running on a soft road. The width of the tire could affect the coefficient of the rolling resistance, but the character parameters of soft roads were the major factors affecting coefficient of the rolling resistance. When the vehicle was driven on soft road, the movement of the vehicle could be prevented by soft soil because not all soil counterforce were effective, for example, some of the resistance forces did not produce propulsive force but were consumed to make soil deformation. The character parameters of soft roads in Institute of Changchun Wetland were measured and the CI was calculated. The rolling resistance of a wheel on real compact terrain was calculated based on Bakker's terramechanics pressure-sinkage equation. The results showed that the rolling resistance was less than 0.03 when the vehicle ran on concrete road, less than 0.1 on hard road, and greater than 0.2 on sand. Therefore, the rolling resistance of 0.2 was considered as the critical value for soft road identification. In a real condition when a vehicle ran on a road, by real-time monitoring the running condition of a vehicle and its engineer on real roads, the coefficient of the rolling resistance could be calculated based on the longitudinal force equation using the engine transient output torsion. If the obtained coefficient of the rolling resistance was greater than 0.2, the vehicle would run at a soft road pattern and pass through the soft road more quickly. In a test study, the accuracy of a vehicle successfully identifying road condition reached 90%, confirming that the rolling resistance-based soft road identification method proposed here was reliable. [ABSTRACT FROM AUTHOR]

Acute respiratory distress syndrome (ARDS) is a clinical syndrome defined by acute onset of hypoxemia and bilateral pulmonary opacities not fully explained by cardiac failure or volume overload. At present, there is no specific drug treatment for ARDS, and the mortality rate is high. The reason may be that ARDS has rapid onset, rapid progression, complex etiology, and great heterogeneity of clinical manifestations and treatment. Compared with traditional data analysis, machine learning algorithms can automatically analyze and obtain rules from complex data and interpret them to assist clinical decision making. This review aims to provide a brief overview of the machine learning progression in ARDS clinical phenotype, onset prediction, prognosis stratification, and interpretable machine learning in recent years, in order to provide reference for clinical.

Objective: To investigate the clinical characteristics of pulmonary artery sarcoma (PAS) and to improve doctors' awareness and the early diagnosis of this disease., Methods: The clinical data of 9 cases confirmed by operation and pathology of PAS from November 2001 to November 2012 in Beijing Anzhen Hospital were reviewed. The clinical characteristics, laboratory tests, imaging manifestation, pathology as well as follow-up were studied. Survival was determined by the Kaplan-Merier method., Results: (1)Main clinical manifestations were chest distress (8/9), palpitation (2/9), syncope (2/9), cough (2/9), weight loss (2/9) and chest pain (1/9). (2)Lactate dehydrogenase (LDH) , high-sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR) were all elevated to different extents, but D-Dimer remained in the normal range. (3) Seven cases received CTPA examination and evidenced filling defect in the main pulmonary artery trunk (6/7), left pulmonary artery (6/7), right pulmonary artery (7/7). 7 cases received TTE examination and showed enlarged right ventricle (6/7) : mean right ventricular end-diastolic diameter was (38.54 ± 16.30) mm; enlarged right atrium (7/7): mean right atrium diameter was (55.11 ± 5.45) mm; and tricuspid insufficiency (7/7) : estimated mean pulmonary artery pressure was (81.14 ± 21.17) mmHg (1 mmHg = 0.133 kPa) , and pulmonary stenosis (5/7) . Four cases received deep venous ultrasound examination and deep venous thrombosis (DVT) was found in 1 patient. Four cases received Ganz catheter examination and the preoperative and postoperative mean pulmonary artery pressure was (52.00 ± 5.23) mmHg and (23.00 ± 5.60) mmHg, respectively. (4) All 9 patients received surgery and intimal sarcoma was diagnosed in all of them. Leiomyosarcoma was diagnosed in 3 cases, leiomyo-angiosarcoma was diagnosed in 1 case, undifferentiated sarcomas was diagnosed in 1 case. (5)The 1-, 3- and 5-month survival was 71.4%, 53.6% and 35.7%, respectively, median survival time was 5 months post surgery., Conclusion: PAS is difficult to differentiate with PTE. PAS should be suspected in patient with right atrium, right ventricular enlargement and early appeared right heart failure, and normal D-Dimer level. Outcome for PAS patients is poor despite surgery in this cohort.

Objective: To explore the eye complication of nasopharyngeal carcinoma (NPC), to analysis the clinical manifestation, CT characteristics and pathological diagnosis of eye complications of NPC and to provide the base for early diagnosis of NPC., Method: To retrospectively study of 82 cases eye complications in 562 cases NPC, to study their clinical manifestation, CT characteristics and pathological diagnosis., Result: The clinical studies showed that eye complication cases were occurred in 82 cases of 562 NPC cases (14.6%). Thirty-six cases in left and 37 cases in right eye, 9 cases in bilateral eyes. Sixty-five cases came from Guangdong, while the others 17 cases come from 5 provinces. There were 9 kinds of eye manifestation. CT appearances: 40 cases suffered from skull base distracted, 6 cases with orbit involved, 2 cases ( in left eyes) with orbit metastasis, 12 cases with nose-sinus involved, 68 case with parapharyngeal space involved, 49 cases with soft issue in wall of styloid process involved (there were many kind of shows in the same case, so the data were repeated in these cases)., Conclusion: There were multiplicity and complexity in eye complication of NPC. Ophthalmologists should think highly of these cases.

Objective: To evaluate the effects of the fusion gene of ubiquitin (Ub) and Porcine Reproductive and Respiratory Syndrome virus (PRRSV) M gene on the immune response in inoculated mice., Methods: Mouse Ub gene and PRRSV M gene were amplified by RT-PCR from BALB/c mice spleen cells and PRRSV Ch-1a strain, respectively, and the M and Ub gene (U-M) was fused by SOE PCR. Therefore, pVAX1-U-M and pVAX1-M recombinant plasmid were constructed for eukaryotic expression., Results: The fusion U-M and M protein expressions were verified in transfected BHK-21 cells by indirect fluorescence assay. Furthermore, both pVAX1-M and pVAX1-U-M induced specific humoral and cellar immune responses against PRRSV in the recombinant plasmid injected mice. However, pVAX1-U-M was able to induce higher level of T cell response then that of pVAX1-M (P<0.05), but lower level of antibody (P<0.05)., Conclusion: Expression of U-M fusion gene had ability to enhance specific T cell response against PRRSV, but no effect on stimulation of humoral response in inoculated mice.

Equine interferon-gamma (eIFN-gamma) expressed both in E. coli and baculovirus were evaluated for antiviral activity against recombinant Vesicular Stomatits Virus expressing green fluorescence protein (rVSV-GFP) in EFK-78 cells. The assays were conducted in 96-well plate. Virus infectivity was measured by quantifying GFP-positive cells, instead of quantifying the CPE reduction. Prior to infection of EFK-78 cells with rVSV-GFP, the cells were incubated with eIFN-gamma. The GFP expression in the EFK-78 cells dramatically decreased in the cells treated with eIFN-gamma in a dose-dependent manner, comparing with the mock-treated cells. The titers of antiviral activity were 1 x 10(3) AU/mL and 1 x 10(5) AU/mL of eIFN-gamma expressed from E. coli and baculovirus, respectively. The antiviral activities of the recombinant eIFN-gamma were highly efficient and specific, as it was blocked by mAbs against eIFN-gamma.

Objective: To express a fusion protein of Neisseria gonorrhoeae with a mucosal adjuvant., Methods: The gene coding Loop VI-VIII(PL678) of porin, an out-membrane protein of Neisseria gonorrhoeae, was obtained by PCR. It was inserted into a plasmid fused with subunit B of heat labile enterotoxin. The recombinant was transformed in E. coli. The expression of fusion protein was analysed by ELISA, SDS-PAGE and Western-blot., Result: Fusion protein with LTB was successfully expressed, and displayed both the ability of binding GM1 and the reactogenicity with polyclonal antibodies against Neisseria gonorrhoeae., Conclusion: The expression of fusion protein laid a foundation for the study of the intramolecular vaccine against Neisseria gonorrhoeae.

Objective: To examine the expression of apoptosis-related genes c-IAP2 and caspase-4 in head and cervical undifferentiation cell carcinoma, as well as to investigate the role and mechanism of the two apoptosis-related genes in head and cervical undifferentiation squamous cell carcinoma., Method: Sixty-six historily confirmed specimen of head and cervical undifferentiation squamous cell carcinoma were subjected for immunohistochemical staining to analyze the expression of c-IAP2 and caspase-4, in addition 5 cases of normal nasal mucosa tissue were selected as control., Result: 1. Higher level expression of c-IAP2 protein was detected in the head and cervical undifferentiation squamous cell carcinoma specimen compared with normal nasal mucosa(P < 0.05), and the expression of caspase-4 was more deletion in it than in normal nasal mucosa(P < 0.05). 2. The expression of c-IAP2 protein was positive correlation with clinical prognosis, not correlated with clinical staging. The expression of caspase-4 protein was negative correlated with clinical prognosis, not correlated with clinical staging, too. 3. The expression of c-IAP2 was negative correlated with the expression of caspase-4., Conclusion: It indicates that in tissue of head and cervical undifferentiation squamous cell carcinoma, c-IAP2 is activated while caspase-4 is restrained. The signal transduction pathway of apoptosis is arrested, leading to surviving of the tumor cells, which maybe directly associated with the developing of head and cervical undifferentiation squamous cell carcinoma, and also with the failure of tumor treatment.

Objective: To find out the mechanism of Tongxinluo Capsule on anti-apoptosis of cardiac myocyte due to ischemia/reperfusion., Methods: Mouse myocardium of ischemia/reperfusion model was observed for evaluating the activity of superoxide dismutase (SOD), the level of malondialdehyde (MDA), the apoptotic index of cardial myocyte and the expression of apoptosis correlation protein bcl-2 and bax., Results: Tongxinluo Capsule could raise the activity of SOD and decrease the level of MDA. And it could depress cardial myocyte apoptosis caused by ischemia/reperfusion through up-regulating bcl-2 expression and down-regulating bax expression., Conclusion: Tongxinluo Capsule could protect cardial myocyte well to avoid injury due to ischemia and reperfusion.