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In recent years, energy-dissipation devices have gained significant attention in seismic protection engineering because of their effectiveness in mitigating the destructive effects of earthquakes. Inspired by an origami pattern invented by Ron Resch, in this study, we propose a novel type of energy-dissipation brace to guide the deformation process and prevent the global buckling of engineering structures. To this end, a parametric geometric model is developed, followed by exploring the effects of different geometric parameters on structural collapse modes. Subsequently, by using hierarchical clustering, the collapse modes are classified into four groups. Finally, an optimal design is introduced to improve energy absorption during quasi-static axial crushing while reducing the initial peak force. The results show specific parameters play a decisive role in determining the collapse modes of the structures. Each group is associated with a particular force-displacement curve characterized by specific properties. We demonstrate that the proposed structural design optimization process reduces the initial peak force by 15.6% without affecting the specific energy absorption. This study provides insights into the application of origami-inspired structures in the design and development of high-performance energy-dissipation braces. [ABSTRACT FROM AUTHOR]

Transvaginal 4-D hysterosalpingo-contrast sonography with SonoVue (TV 4-D HyCoSy) is the preferred imaging method for evaluating tubal patency. However, venous intravasation in 4-D HyCoSy may affect the diagnosis of tubal patency. The objective of this study was to analyze influencing factors of venous intravasation during TV 4-D HyCoSy. This study included 643 infertile patients who underwent TV 4-D HyCoSy. We analyzed the relationship between the incidence of venous intravasation and patients' basic clinical data, endometrial thickness, inspection timing (clean day of menstruation) and tubal patency. A total of 169 (26.28%) patients exhibited intravasation during TV 4-D HyCoSy. The following are risk factors for venous intravation: secondary infertility, type C + C, type B + C and type B + B in bilateral fallopian tubal patency grouping; endometrial thickness ≤5.45 mm; and taking TV 4-D HyCoSy after menstruation ≤6 d. Infertility duration, intrauterine lesions, a history of pelvic inflammatory disease and a history of pelvic surgery were uncorrelated with venous intravasation. To reduce the incidence of venous intravasation, TV 4-D HyCoSy should be performed 7-10 d after menstruation or when endometrial thickness is thicker than 5.45 mm. [ABSTRACT FROM AUTHOR]

Aim: The purpose is to investigate pain perception during transvaginal four‐dimensional hysterosalpingo‐contrast sonography (TV 4D‐HyCoSy) and factors influencing pain severity. Methods: This was a retrospective study included 340 women who underwent TV 4D‐HyCoSy examination from January 2016 to October 2017. The factors were recorded, including age, childbearing history, infertility type, history of pelvic inflammation, pelvic surgery, history of uterine manipulation, history of ectopic pregnancy, atropine delivery mode, uterine position, uterine malformation, uterine lesion, fibroid, intrauterine adhesion, polycystic ovary, endometrial implantation cyst, dysmenorrhea score, the degree of patency of fallopian tube and contrast agents dosage. Pain was evaluated during and after TV 4D‐HyCoSy. The time point of peak pain was evaluated and the influencing factors of moderate/severe pain were analyzed. Results: The highest pain occurred at contrast instillation. The independent influencing factors of moderate/severe pain were age (P = 0.021), dysmenorrhea score (P = 0.003) and tubal patency (P < 0.001). Further analysis showed that age affected the pain score when TV 4D‐HyCoSy started and the peak pain occurred. Dysmenorrhea score and tubal patency affect the pain score at most time points. Conclusion: Age, dysmenorrhea score and tubal patency are factors influencing the severity of pain during TV 4D‐HyCoSy. [ABSTRACT FROM AUTHOR]

Background: Four-dimensional hysterosalpingo-contrast sonography (4D-HyCoSy) is the preferred way for evaluating fallopian tubal patency and it associated with higher rate of spontaneous conception. However, Few studies have evaluated the influencing factors of spontaneous conception in 4D-HyCoSy and suggested ways to choose treatment options after 4D-HyCoSy. The study was to evaluate the correlation between spontaneous conception outcome and the patients' clinical characteristics as well as tubal patency in infertile women to provide reference on ways to manage the patient after 4D-HyCoSy.Methods: This was a retrospective study and analysis of two hundred and eighty three (283) infertile patients who underwent a 4D-HyCoSy between December 2014 and October 2017 in our center. Eligible patients were those whose partners semen parameters were normal when based on World Health Organization (WHO) criteria, and had spontaneous conception without clinical interventions after 4D-HyCoSy.Result(s): One hundred and sixteen patients (40.9%) conceived spontaneously and the mean conception time was (8.8 ± 0.3) months. Within a year after 4D-HyCoSy, the spontaneous conception rate was highest in type VI(62.5%), followed by type IV (46.2%), type III (44.4%), type V (39.4%), type II (33.9%) and type I (14.8%). With Cox regression analysis, two factors associated with spontaneous conception outcome appeared to increase spontaneous conception rate: patients with type IV or type VI tubes and duration of infertility less than 2 years. The age, type of infertility, multiparas, history of pelvic surgery, history of uterine cavity operation, uterine fibromyomata and polycystic ovary were unrelated to spontaneous conception outcome after 4D-HyCoSy.Conclusion(s): This study showed that some infertile women could succeed in spontaneous conception after 4D-HyCoSy. Hence, We recommend the usage of 4D-HyCoSy as first line for tubal patency test and infertile patients should be advised to accept 4D-HyCoSy examination as soon as possible. Expectant treatment of about 8-9 months is reported to be feasible for infertile women whose 4D-HyCoSy findings showed one tube patency or poor patency. Alternatively, an immediate clinical intervention is recommended for those with bilateral obstructed tubes . [ABSTRACT FROM AUTHOR]