The long service life and high reliability of SiC sliding bearings are crucial for the long-term normal operation of aerospace power equipment.In response to the fracture phenomenon observed in the sliding bearing assembly of a certain delivery pump during operation,this paper analyzes the issue from the perspectives of stress characteristics and thermal expansion effects,proposing a structural optimization design method based on temperature coefficient compensation.The research indicates that the primary cause of bearing fracture is the difference in thermal expansion coefficients between the bearing and the metal rotor under elevated temperatures,leading to axial loosening of the bearing.Additionally,the gap between the bearing and the pin,combined with unstable lubrication of the friction pair,exacerbates bearing stalling and pin impact,ultimately causing cracks and localized chipping.By optimizing the bearing structure and employing a rubber pad for torque transmission,this issue has been successfully resolved.The improved structure demonstrated high reliability and stability in bench tests,providing important theoretical and technical references for the design of bearings under similar extreme operating conditions.

Objective To assess the incidence of contrast-induced nephropathy(CIN)in patients with chronic thromboembolic pulmonary hypertension(CTEPH)after receiving balloon pulmonary angioplasty(BPA),and to evaluate the effect of the contrast agents on renal function.Methods A total of 143 CTEPH patients,who received BPA at the China-Japan Friendship Hospital of China from December 2018 to May 2022,were enrolled in this study.The clinical data,hemodynamic indicators,and serum creatinine(SC)concentrations within one week before and 48-72 h after BPA were collected.The estimated glomerular filtration rate(eGFR)was calculated according to the Modification of Diet in Renal Disease(MDRD)formula.The SC concentration and eGFR changes before and after each BPA procedure were compared.The incidence of CIN and its risk factors were evaluated,and the changes in hemodynamics,SC and eGFR after the initial and last time of BPA treatment were analyzed.Results A total of 192 BPA procedures were performed in 115 CTEPH patients,including 88 BPA procedures in males and 103 BPA procedures in females.The mean amount of contrast agent used for each BPA was(145.58±47.26)mL.After BPA,12 patients developed 13 times of CIN,with an incidence of 6.8％.There was no significant differences(P＞0.05)in the baseline characteristics and SC concentration before BPA between CIN patients and non-CIN patients.In terms of the hemodynamic indexes,the mixed venous oxygen saturation(SvO2)in CIN patients was significantly lower than that in non-CIN patients(58.58％±10.38％vs.66.15％±8.02％,P=0.002),and no statistically significant differences(P＞0.05)in the other hemodynamic indexes existed between CIN group and non-CIN group.No statistically significant differences in SC concentration and eGFR existed before and after each BPA procedure.In patients who had received several BPA procedures,significant improvements in the SC[(78.09±18.760)μmol/L vs.(82.26±21.37)μmol/L,P＜0.001]and eGFR[(86.08±21.22)mL/(min·1.73 m2)vs.(82.07±22.05)mL/(min·1.73 m2),P=0.007]was achieved when compared with their baseline values.Conclusion CTEPH patients may develop CIN after receiving BPA treatment.After receiving several BPA treatments the patient's clinical symptoms and hemodynamics can be improved,and the patient's renal function is also significantly improved.

Objective:To evaluate the role of spinal Annexin A3 (ANXA3) in neuropathic pain in mice.Methods:Sixty-four SPF healthy adult male C57BL/6 mice, weighing 22-26 g, aged 8-10 weeks, were divided into 4 groups ( n=16 each) by the random number table method: sham operation group (group S), chronic constriction injury (CCI) group, CCI+ negative control adeno-associated virus AAV-NC group (group CCI+ N) and CCI+ adeno-associated virus AAV-shANXA3 group (group CCI+ sh). The neuropathic pain was induced by CCI of the sciatic nerve in anesthetized animals. The AAV-shANXA3 and AAV-NC (5 μl) were intrathecally injected at 14 days before developing the model in CCI+ N group and CCI+ sh group. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before developing the model and at 7, 14 and 21 days after developing the model. All the mice were sacrificed after the last measurement of pain threshold, the L 4-6 segments of the spinal cord were removed for determination of the expression of ANXA3, phosphorylated nuclear factor-kappa B (p-NF-κB) and ionized calcium-binding adaptor molecule-1 (Iba-1)(by Western blot), expression of ANXA3 mRNA (by real-time polymerase chain reaction), microglial activation (using the immunofluorescence staining), and contents of pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and IL-6 and anti-inflammatory cytokines transforming growth factor-beta (TGF-β) and IL-10 (using enzyme-linked immunosorbent assay). Results:Compared with group S, the MWT was significantly decreased and TWL was shortened after developing the model, the expression of ANXA3 protein and mRNA, p-NF-κB and Iba-1 in spinal cord was up-regulated, the contents of TNF-α, IL-1β and IL-6 were increased, the contents of TGF-β and IL-10 were decreased ( P<0.05), the activation of microglia in the spinal cord was significantly increased, and the cell body was enlarged in group CCI. There was no significant difference in each parameter between group CCI and group CCI+ N ( P>0.05). Compared with CCI+ N group, the MWT was significantly increased on days 14 and 21 after developing the model, the TWL was prolonged on day 21 after developing the model, the expression of ANXA3 protein and mRNA, p-NF-κB and Iba-1 was down-regulated, the contents of TNF-α, IL-1β and IL-6 were decreased, the contents of TGF-β and IL-10 were increased ( P<0.05), and the activation of spinal microglia was decreased in CCI+ sh group. Conclusions:Spinal ANXA3 may be involved in the development and maintenance of neuropathic pain by activating the NF-κB signaling pathway and further promoting microglial activation in mice.

Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor′s professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.

Objective:To investigate the clinical efficacy of minimally invasive percutaneous internal fixation with double screws for delayed union or nonunion of scaphoid fracture.Methods:A retrospective study was conducted to analyze the 12 patients with delayed union or nonunion of scaphoid fracture who had been treated at Department of Hand and Foot Surgery, The Affiliated Hospital of Jining Medical University from March 2021 to December 2023. They were 11 males and 1 female, with an age of (29.9±13.8) years and an interval from injury to surgery of (5.1±2.6) months. They were all treated by minimally invasive percutaneous internal fixation with 2 hollow compression screws. The visual analogue scale (VAS), grip strength (percentage of the affected side to the healthy side), wrist range of motion, modified Mayo wrist score and other data were recorded and compared between pre-surgery and the last follow-up. The incidence of complications was recorded.Results:Follow-up for all patients lasted for (20.8±8.9) months. All patients achieved bony union after (10.1±3.2) weeks with no complications like infection. No post-surgery imaging revealed screw misplacement or penetration. At the last follow-up, the VAS pain score was 0 (0, 1) point, the wrist grip strength 100.6%±7.2%, the wrist flexion 88.3°±2.5°, the wrist dorsiflexion 88.5°±2.2°, and the modified Mayo wrist score (98.3±2.5) points, all significantly better than the pre-surgery values [4 (4, 5) points, 69.1%±16.0%, 61.3°±13.5°, 64.7°±9.1°, and (61.7±10.1) points] (all P < 0.05). Conclusion:In the treatment of delayed union or nonunion of scaphoid fracture, minimally invasive percutaneous internal fixation with double screws shows advantages of minimal invasion, quick fracture healing, fine functional recovery, and no need of bone grafting.

Objective:To evaluate the role of spinal Annexin A3 (ANXA3) in neuropathic pain in mice.Methods:Sixty-four SPF healthy adult male C57BL/6 mice, weighing 22-26 g, aged 8-10 weeks, were divided into 4 groups ( n=16 each) by the random number table method: sham operation group (group S), chronic constriction injury (CCI) group, CCI+ negative control adeno-associated virus AAV-NC group (group CCI+ N) and CCI+ adeno-associated virus AAV-shANXA3 group (group CCI+ sh). The neuropathic pain was induced by CCI of the sciatic nerve in anesthetized animals. The AAV-shANXA3 and AAV-NC (5 μl) were intrathecally injected at 14 days before developing the model in CCI+ N group and CCI+ sh group. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before developing the model and at 7, 14 and 21 days after developing the model. All the mice were sacrificed after the last measurement of pain threshold, the L 4-6 segments of the spinal cord were removed for determination of the expression of ANXA3, phosphorylated nuclear factor-kappa B (p-NF-κB) and ionized calcium-binding adaptor molecule-1 (Iba-1)(by Western blot), expression of ANXA3 mRNA (by real-time polymerase chain reaction), microglial activation (using the immunofluorescence staining), and contents of pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and IL-6 and anti-inflammatory cytokines transforming growth factor-beta (TGF-β) and IL-10 (using enzyme-linked immunosorbent assay). Results:Compared with group S, the MWT was significantly decreased and TWL was shortened after developing the model, the expression of ANXA3 protein and mRNA, p-NF-κB and Iba-1 in spinal cord was up-regulated, the contents of TNF-α, IL-1β and IL-6 were increased, the contents of TGF-β and IL-10 were decreased ( P<0.05), the activation of microglia in the spinal cord was significantly increased, and the cell body was enlarged in group CCI. There was no significant difference in each parameter between group CCI and group CCI+ N ( P>0.05). Compared with CCI+ N group, the MWT was significantly increased on days 14 and 21 after developing the model, the TWL was prolonged on day 21 after developing the model, the expression of ANXA3 protein and mRNA, p-NF-κB and Iba-1 was down-regulated, the contents of TNF-α, IL-1β and IL-6 were decreased, the contents of TGF-β and IL-10 were increased ( P<0.05), and the activation of spinal microglia was decreased in CCI+ sh group. Conclusions:Spinal ANXA3 may be involved in the development and maintenance of neuropathic pain by activating the NF-κB signaling pathway and further promoting microglial activation in mice.

Turning to critical illness is a common stage of various diseases and injuries before death. Patients usually have complex health conditions, while the treatment process involves a wide range of content, along with high requirements for doctor′s professionalism and multi-specialty teamwork, as well as a great demand for time-sensitive treatments. However, this is not matched with critical care professionals and the current state of medical care in China. Telemedicine, which shortens the distance of medical professionals and the gap of disease diagnosis and treatments in various regions through electronic information, can effectively solve the current problem. Therefore, there is an urgent need to develop a standardized, high-quality visualization telemedicine round system .Therefore, experts have been organized to search domestic and foreign literature on telemedicine round for critically ill patients and to form this consensus based on clinical experiences so as to further improve the level of critical care treatments in regions.

Objective:To investigate the clinical efficacy of minimally invasive percutaneous internal fixation with double screws for delayed union or nonunion of scaphoid fracture.Methods:A retrospective study was conducted to analyze the 12 patients with delayed union or nonunion of scaphoid fracture who had been treated at Department of Hand and Foot Surgery, The Affiliated Hospital of Jining Medical University from March 2021 to December 2023. They were 11 males and 1 female, with an age of (29.9±13.8) years and an interval from injury to surgery of (5.1±2.6) months. They were all treated by minimally invasive percutaneous internal fixation with 2 hollow compression screws. The visual analogue scale (VAS), grip strength (percentage of the affected side to the healthy side), wrist range of motion, modified Mayo wrist score and other data were recorded and compared between pre-surgery and the last follow-up. The incidence of complications was recorded.Results:Follow-up for all patients lasted for (20.8±8.9) months. All patients achieved bony union after (10.1±3.2) weeks with no complications like infection. No post-surgery imaging revealed screw misplacement or penetration. At the last follow-up, the VAS pain score was 0 (0, 1) point, the wrist grip strength 100.6%±7.2%, the wrist flexion 88.3°±2.5°, the wrist dorsiflexion 88.5°±2.2°, and the modified Mayo wrist score (98.3±2.5) points, all significantly better than the pre-surgery values [4 (4, 5) points, 69.1%±16.0%, 61.3°±13.5°, 64.7°±9.1°, and (61.7±10.1) points] (all P < 0.05). Conclusion:In the treatment of delayed union or nonunion of scaphoid fracture, minimally invasive percutaneous internal fixation with double screws shows advantages of minimal invasion, quick fracture healing, fine functional recovery, and no need of bone grafting.

A LAMP-Taqman rapid detection system for porcine pseudorabies virus(PRV)was de-veloped based on LAMP and quantitative PCR.LAMP primers were designed for PRV conserved sequences,and the loop primer modified by the fluorescent quenching group was used as the Taq-man probe.The composition optimization,specificity,sensitivity and repeatability of the LAMP-Taqman system were tested using positive samples and recombinant plasmid as templates.Thirty-eight samples of pork swabs were tested with the commercial LAMP detection kit in parallel to verify the actual detection effect of the LAMP-Taqman detection system.The results showed that the optimal final concentration of each component was as follows:PRV-FIP/BIP 0.8 μmol/L,Bst DNA polymerase 0.7 U/μL,Taq DNA polymerase 0.24 U/μL,dNTPs 1.6 mmol/L,MgSO47.2 mmol/L.This system had good specificity and did not cross-react with other virus samples.The linear correlation coefficient of gradient samples was 0.995,the coefficient of variation of repeatable tests was less than 3.000％,and the minimum detection limit could reach 2.81 ×102 copies/μL.The test results of the actual swab samples were consistent with the commercial isothermal fluores-cence detection reagents.In conclusion,the PRV detection system established by LAMP-Taqman method in this study is specific,sensitive,stable and accurate,and is a reliable technical method suitable for the accurate detection of porcine PRV.

Objective:To investigate the prevalence and related influencing factors of thyroid nodules in different occupational groups in Shijiazhuang City.Methods:Different occupational groups who underwent physical examination at the Second Hospital of Shijiazhuang City from May to December 2015 and had lived there for more than 10 years were selected as the investigation subjects, including workers, farmers, science and technology education personnel, medical and health personnel, civil servants and individual businessmen. Questionnaire survey and thyroid examination were conducted, blood lipid, blood glucose and thyroid hormone levels were tested, and related influencing factors of thyroid nodules were analyzed.Results:A total of 1 440 different occupational subjects were surveyed, and the prevalence of thyroid nodules was 20.35% (293/1 440). The prevalence of thyroid nodules in females (22.59%, 159/704) was significantly higher than that in males (18.21%, 134/736), and the difference was statistically significant (χ 2 = 4.26, P = 0.039). There was a statistically significant difference in the prevalence of thyroid nodules in different age groups (χ 2 = 73.87, P < 0.001), with the highest prevalence in the 70 - 80 age group (43.75%, 21/48). There was a statistically significant difference in the prevalence of thyroid nodules among different occupational groups (χ 2 = 36.56, P < 0.001), with the highest prevalence in individual businessmen (31.84%, 78/245). By univariate analysis, the prevalence of thyroid nodules in people with good economic status [27.45% (42/153) vs 19.48% (248/1 273)], radiation exposure history [26.39% (109/413) vs 17.92% (184/1 027)], and diabetes history [33.71% (30/89) vs 19.47% (263/1 351)] was higher (χ 2 = 5.35, 13.06, 10.45, P < 0.05). Conclusions:The prevalence of thyroid nodules in occupational group in Shijiazhuang City is relatively high, and the prevalence of thyroid nodules in females is significantly higher than that in males. Economic status, radiation exposure history and diabetes history are the main influencing factors.