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Background: The contact force–deformation relation between two spheres is one fundamental property which determines the mechanical response of the colliding bodies. In general, collisions of solid spheres occur in a very short time, so a highly accurate and a non-contact measurement method is required. Objective: In this study, a concept for the experimental determination of contact force–deformation curves of two colliding spheres is presented. Thereby two identical steel spheres collide by using a pendular setup and the sphere's velocities are measured by Laser Doppler Vibrometers (LDVs). Methods: The displacements are obtained by integrating the velocity with time and the accelerations are obtained by differentiating the velocity with time. From these values, the deformation and the contact forces can be calculated. Then, the elastic results are compared with the Hertzian theory of impact and experiments are conducted with elasto-plastic spheres. Results: Although the deformations are in good agreement with these analytical values, the influence of numerical differentiation is observed in the contact force. However, it is shown that the elastic contact force–deformation curve of two colliding spheres can be obtained with reasonable accuracy by using LDVs. For elasto-plastic spheres the coefficient of restitution became smaller than for the purely elastic case, and the force–deformation curve with hysteresis are measured. Conclusions: The results of this study are considered to be reasonable as far as comparisons with those for elastic collisions. Therefore, more detailed verification by numerical analysis, such as finite element analysis, is desirable. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Bronchial complications owing to the airway anastomosis in lung transplantation are important causes of morbidity and mortality. They occur in up to 27% of cases as defined by stenosis, necrosis, and dehiscence. Treatment depends on the type of complication. Objective: To report our experience to treat this complication. Methods: Between 2000 and 2007, we performed 71 lung transplants of which 36 were bilateral. The total number of anastomoses was 107:52 to the right and 55 to the left. The telescoping technique was initially used (14 initial unilateral transplants), and after October, 2003 it was changed to an end-to-end anastomosis (57 transplants and 93 anastomoses). Results: Eight patients developed bronchial complications including two that were bilateral. There were 4 stenosis, 3 dehiscences, and 3 necrosis complications (9.4%). The complication rate for telescoping anastomosis was 21.4%, and for the end-to-end technique, 7.5%. The treatment of the stenosis used metallic or plastic self-expandable stents. Two bronchial dehiscences resulted in case of bronchopleural fistulae, empyema, and death; the other patient experienced spontaneous resolution. Concerning bronchial necrosis, 1 patient developed fistulization to the pulmonary artery and massive hemoptysis, and the other with bilateral necrosis, a spontaneous resolution. Conclusion: Our bronchial anastomosis complication rate was comparable with that in other reports. The rate for the telescoping technique was greater compared with the end-to-end technique. The treatment of bronchial stenosis with a self-expandable prosthesis showed good results. [Copyright &y& Elsevier]

Minamoto H, Antonângelo L, da Silva A G P, Gallo C P, de Andrade e Silva F B, Fenezelian S, Rodrigues O R, Jatene F, Saldiva P & Capelozzi V L (2003) Histopathology 43, 427–443 Tumour cell and stromal features in metastatic and non-metastatic non-small cell lung carcinomas Tumour cell behaviour depends on the interactions between nuclear genetic changes in the malignant cells and a stroma favourable for growth, invasion and metastasis. To evaluate such interactions, we studied the relationship between tumour cell and stromal features for proliferative factors, p53, microvessel density and metalloproteinases, controlled for the extent of the primary lesion (T1 to T4), in early (non-metastatic) and late (metastatic) non-small cell lung carcinomas (NSCLC). Variables were examined for differences and correlations in the frequency of p53, AgNOR, CD34 and MMP-9 expression in primary lesions and metastases of NSCLC using a general linear model. The patients included 58 males and 22 females (mean age 62 ± 9 years) with 19 T1 (23.8%), 40 T2 (50.0%), 14 T3 (17.5%) and seven T4 (8.8%). In late disease, AgNOR and p53 were statistically related to the extent of the primary lesion, whereas in early disease AgNOR tended to be increased in tumours without metastasis, while p53 expression tended to decrease progressively in tumours with metastasis. Microvessel density in late disease was of no statistical significance, whereas in early disease strong CD34 expression was seen in tumours with metastasis, being at its maximum in T3 primary lesions. The best marker for the extent of the lesion and its progression was MMP-9, with greater expression by tumours with metastasis than those without. Different tumour cell and stromal interactions control metastasis and therefore the biological risk of NSCLC. A panel of molecular markers, such as p53, MMP-9 and CD34 could help to identify subgroups of patients that could benefit from adjuvant therapy. [ABSTRACT FROM AUTHOR]

This paper deals with two-dimensional motion analysis of vehicles damaged due to collision. Various parts of vehicles are damaged due to collision in general. The effects of the damage in vehicle body and wheels on the vehicle motions are investigated. The center of gravity of the vehicle and the polar moment of inertia are changed by the deformation of vehicle body. Furthermore, the geometrical relations of wheels like wheelbase, treads and steering angles may be changed by damage of the wheels. Thus the vehicle loses symmetry with respect to the vehicle axis. The four-wheel vehicle model is extended to take into account the vehicle damage due to collision. The motions of damaged vehicles are compared with those of undamaged vehicles. It is found that vehicle damages have a significant influence on vehicle motion after impact. [ABSTRACT FROM AUTHOR]

This paper deals with two-dimensional motion of vehicles. Since the general four-wheel vehicle model is statically indeterminate, the motion of vehicles has been analyzed by replacing the vehicle with the equivalent two-wheel one proposed by E. Marquard. Because this approximation is based on the axisymmetry of vehicles, it causes significant errors in the general case. To improve the accuracy of the analysis of vehicle motion, a four-wheel model is suggested. In this model, it is assumed that the chassis remains in a flat plane during motion. By introducing this condition, the motion of the vehicle can be analyzed. Several results from the four-wheel model and the equivalent two-wheel model are shown for comparison, and the vehicle trajectories with time are discussed. [ABSTRACT FROM AUTHOR]

Background Airway complications after lung transplantation are the major cause of morbidity, affecting up to 33% of all cases. Bronchial stenosis is the most common complication. The use of stents has been established as the most effective therapy; however, their removal is recommended after 3–6 months of use. We have been using self-expandable stents as a definitive treatment and remove them only if necessary. For this report, we evaluated the use of self-expandable stents as a definitive treatment for bronchial stenosis after lung transplantation. Methods We performed a retrospective cohort study to evaluate patients with bronchial stenosis from August 2003 to April 2014. Clinical and pulmonary function test data were collected. Results Two hundred lung transplants were performed, 156 of which were bilateral. Sixteen patients experienced airway complications: 4 had dehiscence, 2 necrosis, and 10 bronchial stenosis. Of these patients, 7 had undergone bilateral procedures, and 2 patients developed stenosis in both sides. Twelve anastomotic stenoses were observed. The follow-up after stenting ranged from 1 to 7 years. All patients had increased lung function, and 4 remained stable with sustained increase in pulmonary function without episodes of infection. Three patients required removal of their prosthesis 6 months to 1 year after implantation because of complications. Two patients died owing to unrelated causes. Conclusions Definitive treatment of bronchial stenosis with self-expandable stents is a viable option. The 1st year seems to be the most crucial for determining definitive treatment, because no patients required removal of their stent after 1 year. [ABSTRACT FROM AUTHOR]