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Objective·To explore the feasibility of applying improved pathological section boxes based on image post-processing and 3D printing technology to assisting artificial intelligence (AI) in stitching pathological images of bone tumors.Methods·Bone tumor patients who underwent tumor resection surgery between February 2022 and August 2022 were enrolled. Patients and their postoperative tumor specimens were examined by CT and MRI. The skeletal anatomical landmarks of bone tumors were used to register the preoperative CT, and MRI and the postoperative CT images. The personalized pathological slice box was improved and 3D printed to guide the cutting direction of bone tumor specimens. The large pathological slices were grid-like segmented and performed with hematoxylin-eosin staining. After AI stitching the pathological images, the pathological tumor boundaries were compared with the preoperative radiological boundaries.Results·Four patients with bone tumors (2 bone metastatic neoplasm, 1 osteosarcoma, and 1 chondrosarcoma; 3 males and 1 female) were collected to design the pathological section box with an average age of (40.25±25.70) years. The lesions included 3 cases of femur and 1 case of ilium. The mean maximum tumor diameter was (12.10±4.02) cm. The modified 3D printed pathological section box could fit the surface of bone tumor individually,and overcame the problems of difficult cutting or inaccurate cutting location caused by excessive movement of bone tumor specimens in the primary pathological section box. The pathological boundaries could be completely obtained and compared with the preoperative MRI boundaries for colocalization. The outline features of the section boxes could help AI to restore the permutation of pathological fragments, and the image stitching time decreased from the previous seventy hours to one hour while the boundary coincidence rates increased to 90%.Conclusion·The improved pathological section box of 3D printing can accurately assist AI in stitching pathological images, greatly improve the efficiency of pathological image stitching and achieve the colocalization between preoperative MRI and pathological images of bone tumor specimens.

In order to explore the anti-penetration property of carbon fiber composite materials, a series of experiments need to be carried out. In experiments, 8 g cubic steel fragments penetrated carbon fiber reinforced plastics whose thickness are 5, 10 and 15 mm respectively. The velocity of fragments was obtained, the situation of target was observed, fragments and carbon fiber were recovered. The numerical simulations were carried out according to the situation of experiments. The process of fragments penetrating carbon fiber composite target was explored, and the failure mechanism of carbon fiber composite target was also explored. The relationship between the failure mode and velocity of fragments could be described as follows: when the fragment velocity exceeds the ballistic limit, the main form of target damage is fiber shear failure; when the fragment velocity is lower than the ballistic limit, the damage forms of the target include fiber shear failure, fiber tensile failure, matrix cracking and fiber layer delamination, and their proportions change with the fragment velocity. [ABSTRACT FROM AUTHOR]

Objective To investigate the adverse effects of low-concentration isocyanate exposure on airway inflammation and lung function and to explore the application of fractional exhaled nitric oxide (FeNO) in occupational health examinations of isocyanate-exposed workers. Methods From 2016 to 2017, a total of 192 workers exposed to isocyanates were selected as the exposure group, and 91 with similar age and gender composition (office and/or logistics personnel) without any exposure to occupational hazards (as references) were studied. Monitoring data of airborne isocyanate concentration in workplaces in the past 5 years were collected. The basic information of all workers was collected, and their lung function, FeNO, and salbutamol bronchial dilation tests were performed. The differences in various indicators among these two groups of workers were compared. Results The airborne isocyanate concentration in workplaces over the past 5 years was significantly lower than the national occupational exposure limit. The forced vital capacity (FVC) and forced expiratory volume in first second (FEV1) of the exposed workers were higher than those of the reference group, while FEV1/FVC was lower than that of the reference group, and the differences were statistically significant (P < 0.001). There was no significant difference in FeNO levels between the exposed workers and the reference workers (P > 0.05). The FEV1/FVC ratio was higher in the exposed workers with exposure time < 7 years than workers with exposure time≥ 7 years (P < 0.05), while there was no significant difference in FeNO levels between these two groups (P > 0.05). There was no significant difference in various indicators of lung function among different workers grouped according to the FeNO levels (P > 0.05). Among 192 exposed workers, 13 had FeNO levels higher than 50 ppb (1 ppb = 1 × 10-9), and among 9 workers receiving bronchial dilation tests 3 workers were positive. Conclusions FEV1/FVC could better reflect the adverse effect of isocyanate, a type of asthmagens, on lung function. FeNO levels cannot indicate the occupational low -level isocyanate exposure, while positive changes shown by bronchial dilation tests in exposed populations occur earlier than changes in lung function. The combination of FeNO measurement and bronchial dilation tests could have certain predictive value for diagnosing and screening occupational asthma. [ABSTRACT FROM AUTHOR]