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ObjectiveTo improve the response capabilities to disasters and prevent major epidemics， it is of practical use to study the capability evaluation system of the national emergency medical rescue team that combines theoretical training and practical exercises， to enhance the overall quality of the teams.MethodsFirst， a capability assessment system for the national emergency medical rescue team was constructed based on the INSARAG External Classification （IEC） standards of the national emergency medical rescue team. Then， based on the outcome based education （OBE） concept， we conducted innovative research on the curriculum design and exercise programs for team building and member training. Finally， an empirical analysis was conducted on the effectiveness of the evaluation system and training exercises based on the statistical analysis of the comprehensive quality evaluation of the Shanghai national emergency medical rescue team from 2020 to 2023， as well as the empirical analysis of the rescue exercise on the Cruise of spectrum.ResultsBased on the linear regression analysis of each core competency indicators， the five core competencies in the evaluation system， including rescue skills， medical and health knowledge， disaster coping ability， team cooperation ability， and mental resilience training， were positively correlated with the cumulative number of trainings （r=0.71， r=0.76， r=0.81， r=0.84， r=0.96，all P

Objective To investigate the effect and mechanism of human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-exos) on renal ischemia/reperfusion (I/R) injury in rats based on ferroptosis-related SLC7A11/GPX4 pathway. Methods HucMSCs were cultured and exosomes were obtained through differential centrifugation. The morphology of exosomes was observed by transmission electron microscopy, and the particle size was detected by nanoparticle tracking technology. Western blotting was used to determine the expression levels of surface marker proteins. The rat model of renal I/R injury was established by clamping both kidneys for 45 min, followed by reperfusion for 24 h. Thirty male SD rats (7 to 8 weeks old, 200 to 230 g) were randomly divided into 5 groups (n=6): Sham group, Sham+erastin group (SLC7A11 inhibitor), I/R group, Exo group, and Exo+erastin group. The Sham+erastin and Exo+erastin groups were intraperitoneally injected with erastin 10 mg/kg 30 min before modeling. The Exo group and Exo+erastin group were injected with HucMSCs-exos 20 μg via caudal vein 15 min before renal pedicle clamping. The renal samples were harvested 24 h after recovery and reperfusion. The levels of serum creatinine (Cr) and blood urea nitrogen (BUN) were detected. HE staining was employed to observe the pathological changes in the kidney tissue, and Paller score were calculated. The levels of ferroptosis-related markers, divalent ferrous ion (Fe2+), malondialdehyde (MDA), reactive oxygen species (ROS) and glutathione (GSH) in the renal tissues were detected. Western blotting was used to assess the expression levels of the ferroptosis-related protein SLC7A11 and glutathione peroxidase 4 (GPX4) in the kidney tissue. Results Compared with the Sham group, increased serum BUN and Cr levels (P < 0.05), obvious pathological injury in kidney tissue, elevated Paller score, Fe2+ and MDA contents (P < 0.05), increased ROS level (P < 0.05), and decreased GSH content and SLC7A11 and GPX4 protein levels (P < 0.05) were observed in the I/R group. Exo treatment reversed above changes when compared with the I/R group (all P < 0.05). The protective effects of HucMSCs-exo on ferroptosis and renal I/R injury were significantly attenuated by administration of erastin, a SLC7A11 inhibitor. Conclusions HucMSCs-exos can significantly attenuate renal I/R injury and play a protective role, and its mechanism may be related to the inhibition of ferroptosis by up-regulating the SLC7A11/GPX4 pathway.

The end face meshing worm drive with tapered roller envelope has many simultaneous meshing tooth pairs and can eliminate clearance. According to the gear meshing principle and differential geometry principle, the meshing mathematical model of the transmission pair is established, the worm tooth surface equation and meshing function are deduced, and the meshing performance calculation formula is obtained. Matlab software is used to analyze the effects of small end radius, throat diameter coefficient and half cone angle of cone on the meshing performance evaluation parameters of the transmission pair induced normal curvature, lubrication angle, relative entrainment speed and self rotation angle. The analysis results show that the transmission pair has good meshing performance.

Based on the research of worm gear pair and double roller enveloping hourglass worm without backlash, a new type of worm drive with end roller enveloping is proposed. Based on the principle of gear meshing, the coordinate system of end roller enveloping hourglass worm is established. The equations of worm gear meshing function, meshing equation, lubrication angle, self rotation angle, induced normal curvature and relative entrainment velocity are derived. Matlab is used to analyze the influence of its own parameters on the transmission performance. The results show that: The worm lubrication angle, relative entrainment speed and induced normal curvature can obtain good data, and the self rotation angle of worm gear needs to be optimized.

Based on the meshing theory of single roller enveloping end face worm drive,the distribution of contact line and the length of contact line on the cylindrical surface of the drive pair,and the self-rotation angle of the roller,and the self-rotation angle velocity of the roller are analyzed. The concepts of contact line wrap angle and contact line density are proposed to describe the spatial complexity of single contact line on roller cylinder and the density of contact wire on roller cylinder. Meanwhile,the calculation formulas of contact wire wrap angle and contact wire density are derived and analyzed numerically. The calculation formula of contact line on cylindrical surface of roller in specific space distribution area is deduced and its value is calculated. The average self-rotation angle velocity of roller in height direction is deduced and its value calculated by using numerical integration function of Matlab mathematical tool software. And the angle of roller in meshing period is obtained with the help of numerical integration function of Matlab. The sliding speeds under the condition of whether the roller is fixed or not are analyzed by comparing their values. The results show that the distribution area of contact line of the roller cylinder is very small in the specific space,the roller has excellent rotation performance,and the transmission pair has excellent anti sliding effect.

Objective: To investigate the relation of clinicopathological characteristics and RCN1 and GRP78 expression levels in colorectal cancer, and explore their prognostic value. Methods: The expression of RCN1 and HSPA5 mRNA in colorectal cancer( CRC) was examined using the TCGA and UALCAN databases, and clinical samples were obtained for immunohistochemistry to confirm the expression of both. Then, the correlation with clinicopathological features and its prognostic value were analyzed. Results: According to a bioinformatics analysis, RCN1 and HSPA5 mRNA were both significantly overexpressed in CRC and had a positive correlation.The expression of RCN1 was correlated with N stage and TP53 mutations, the expression of HSPA5 was higher in mucinous adenocarcinomas. In CRC tissues, RCN1 and GRP78 protein were both strongly expressed and localized in the cytoplasm. GRP78 expression was significantly correlated with T stage. The Kaplan-Meier survival analysis curve indicates that patients with higher RCN1 expression had significantly shorter DFS than those with lower expression and a tendency toward shorter OS.According to COX regression analysis,DFS in CRC was found to be independently associated with tumor nerve invasion, TNM stage, and high RCN1 expression, Correlation analysis: RCN1 and GRP78 expression were positively associated in CRC. Conclusion: RCN1 is an independent risk factor for a poor prognosis in colorectal cancer (CRC) and has a positive correlation with GRP78 expression. [ABSTRACT FROM AUTHOR]

The mandibular canine usually has a single root with a single canal. It is rarely to see a mandibular ca⁃ nine with two roots and two toot canals. A case of a patient who has a right mandibular canine with two roots and two root canals was reported. Cone beam computed tomography (CBCT) comprehensively demonstrated the root canal system and especially provided the information of canal varieties and complex canal before operation. CBCT can improve the discovery rate of canal varieties, guide root canal treatment and prevent missed roots in tooth extraction.

To improve the corrosion resistance of mechanical components, cold sprayed assisted laser remelting was used to synthesized HEA coatings with different Co contents AlCoxCrFeNiCu(x = 0,0. 5,1,1. 5,2). The effects of the change in Co content on the phase structure, microstructure and corrosion resistance of the alloy coating was characterized via XRD, SEM, EDS, TEM, electrochemical test system and other equipment tests. The results show that the laser remelting AlCoxCrFeNiCu HEA coatings is composed of simple BCC and FCC phases, when x=1, the lattice distortion of HEA coatings is the largest, with the increase of Co content, the equiaxed dendrites of the laser remelting AlCoxCrFeNiCu HEA coatings become less and more and gradually refine, and the spacing of columnar dendrites first increases and then decreases. In 3. 5% NaCl corrosive medium, when x = 0. 5, there is slight segregation of Cu element in HEA coatings, and a small amount of pitting occurs. The laser remelting synthesized AlCo0.5CrFeNiCu HEA coatings has the most positive self-corrosion potential, the corrosion current density reaches the minimum, the corrosion rate was 2. 28×10-3 mm/a, the AlCo0.5CrFeNiCu HEA coating shows good corrosion resistance. [ABSTRACT FROM AUTHOR]

Skin aging is the most intuitive and obvious sign of the human aging processes. Qualitative and quantitative determination of skin aging is of particular importance for the evaluation of human aging and anti-aging treatment effects. To solve the problem of subjectivity of conventional skin aging grading methods, the self-organizing map (SOM) network was used to explore an automatic method for skin aging grading. First, the ventral forearm skin images were obtained by a portable digital microscope and two texture parameters, i.e. , mean width of skin furrows and the number of intersections were extracted by image processing algorithm. Then, the values of texture parameters were taken as inputs of SOM network to train the network. The experimental results showed that the network achieved an overall accuracy of 80.8%, compared with the aging grading results by human graders. The designed method appeared to be rapid and objective, which can be used for quantitative analysis of skin images, and automatic assessment of skin aging grading.