The objective of this study was to determine the impact of joint rigidity on results of skeleton furniture construction optimisation expressed by the function of minimum material volume. The performed experiments proved that joint rigidity exerts a significant effect on optimisation results both with regard to the difference of individual dimensions of element cross-sections and total construction volume. Gradient optimisation allowed reducing the volume of skeleton constructions by 72 – 76% of their initial volume within the time of less than 1.4 hours.
The presented study is of theoretical nature aiming to perform a numerical analysis of structural strength of skeleton furniture subjected to real useful loads. The objective of the performed investigations was to determine the state and distribution of stresses in the angle joint of a spatial structure of skeleton furniture. Experiments were carried out on dowel and tenon and mortise joints, which belong to the group of flat angle joints. The performed experiments allowed to develop a numerical model of a skeleton construction which was later used to perform calculations determining: reduced stresses according to the von Mises theory, tangential stresses in glue lines of dowel and tenon and mortise joints and tangential stresses in the wood of dowel joints. The results presented in this study are of cognitive nature. They determine values of stresses in joints of the loaded furniture piece and identify places with the greatest effort.
The experiment was performed on 36 Wistar rats. On the first day of the experiment iodoacetate was administered to the left posterior knee joint of the 18 rats which composed Group I. The second group of 18 rats received additionally doxycycline (doxy) through the gastric tube in doses comparable with those of doxycycline used in humans. The experiment lasted 21 days. The animals were sacrificed after 7, 14 and 21 days in groups of 6 rats each. In sections stained with Safranin 0 semiquantitative histochemical intensity tests were performed on articular cartilage glycosaminoglycans (GAG) using a four-point scale (0–3). In the first group examined destructive lesions in the articular cartilage and weak reactivity on GAG were noted at all stages of the experiment. The intensity of GAG staining was higher in the second group after 14 and especially after 21 days, which may suggest a protective action of doxy on articular cartilage.
This article aims to compare the treatment of fragmented coronary process in the context of clinical results. Forty-two dogs of both sexes, aged from 5 months to 2 years, all belonging to the predisposed breeds, were tested. Each patient was subjected to radiological and clinical examination on the basis of which was classified into one of four degrees of dysplasia according to criteria of the International Elbow Working Group. Then the decision towards specific therapeutic procedures, operational or pharmacological, was taken. About 4-12 weeks after the surgery, the control examination was performed. It allowed to assess the post-surgery mobility. The results depended on the age of animal at which treatment was carried out, and the degree of degenerative changes in the joint. The studies have shown that the best results were obtained in a group of dogs aged 5-9 months, in whom a dynamic ulna osteotomy was performed. This indicates the need for early diagnosis of disease and rapid implementation of the treatment, to eradicate the problem of radial- ulnar incongruity, thereby preventing the development of further changes within the joint.