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Background: Toxocariasis is a common zoonotic helminthic disease with worldwide distribution. Seroepidemiological data related to human toxocariasis and its risk factors are limited in the east of Iran. Objectives: The current study evaluated the seroprevalence of toxocariasis and associated risk factors in clinically healthy individuals aged 18 years or older in eastern Iran. Methods: We took 450 samples from clinically healthy individuals referred to medical laboratories for health screening between March and May 2022 in Birjand, Iran. The seroprevalence of IgG antibody against Toxocara was performed using the enzyme-linked immunosorbent assay (ELISA) kit (IBL, Germany). Logistic regression was used to analyze the association between toxocariasis and potential risk factors by SPSS 21.0 software. A probability P value less than 0.05 was considered statistically significant. Results: The sample included 210 (56.6%) men, and 240 women (53.3%) who were aged 18 to 81 years (mean 35 ± 13 years). The Toxocara ELISA was positive in 36 (8%) individuals. The statistical analysis showed that washing hands before eating (odds ratio (OR) = 0.1, 95% CI: 0.05 - 0.3, P < 0.0001), contact with cats and dogs (OR = 0.1, 95% CI: 0.05 - 0.3, P < 0.00001), and raw meat consumption (OR = 4.8, 95% CI: 2.2 - 11.4), P < 0.0004) were risk factors associated with Toxocara infection. Conclusions: The relatively low seroprevalence of Toxocara infection in our study can be caused by environmental and socio-cultural conditions and moderate to high hygiene standards in Birjand. It is suggested that more extensive studies be conducted with larger sample sizes in at-risk groups in this area.

Introduction: To supply safety in the tunnels, it is necessary to construct escape routes and emergency exits that are performed by locating cross passages. Methods: These passages connect two tunnels transversely and apply escape routes. Using temporary steel structures to supply the ring stability in practice and reinforced concrete frame to stabilize the ring permanently can be appropriate to form a solid frame that transfers the opened ring's load to the opening surroundings. In this paper, a 3D finite element simulation was performed to analyze the influence of opening construction in the segmental concrete lining and a temporary support system. Using the simulation, stress and deformation distribution of the steel frame, bolts, and segmental lining were obtained. Results: The results show that by increasing the number of bolts from 18 to 30, the induced stress in the steel frame and bolts decreased to 76 and 59 percent, respectively. In addition, the maximum displacement in the segmental lining and the maximum opening value of the joints decline to 62.7 and 75 percent, respectively. Conclusion: Finally, it can be concluded that the steel frame can be used as a temporary support system.

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