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Due to the difficulties in retrieving both the time-dependent shapes of the vessels and the generation of numerical meshes for such cases, most of the simulations of blood flow in the cardiac arteries use static geometry. The article describes a methodology for generating a sequence of time-dependent 3D shapes based on images of different resolutions and qualities acquired from ECG-gated coronary artery CT angiography. The precision of the shape restoration method has been validated using an independent technique. The original proposed approach also generates for each of the retrieved vessel shapes a numerical mesh of the same topology (connectivity matrix), greatly simplifying the CFD blood flow simulations. This feature is of significant importance in practical CFD simulations, as it gives the possibility of using the mesh-morphing utility, minimizing the computation time and the need of interpolation between boundary meshes at subsequent time instants. The developed technique can be applied to generate numerical meshes in arteries and other organs whose shapes change over time. It is applicable to medical images produced by other than angio-CT modalities., (© 2024. The Author(s).)

The aim of this paper is to propose a new non-invasive methodology to estimate thermogenesis in newborns with perinatal asphyxia (PA) undergoing therapeutic hypothermia (TH). Metabolic heat production (with respect to either a neonate's body mass or its body surface) is calculated from the newborn's heat balance, estimating all remaining terms of this heat balance utilising results of only non-invasive thermal measurements. The measurement devices work with standard equipment used for therapeutic hypothermia and are equipped with the Global System for Mobile Communications (GSM), which allows one to record and monitor the course of the therapy remotely (using an internet browser) without disturbing the medical personnel. This methodology allows one to estimate thermogenesis in newborns with perinatal asphyxia undergoing therapeutic hypothermia. It also offers information about instantaneous values of the rate of cooling together with values of remaining rates of heat transfer. It also shows the trend of any changes, which are recorded during treatment. Having information about all components of the heat balance one is able to facilitate comparison of results obtained for different patients, in whom these components may differ. The proposed method can be a new tool for measuring heat balance with the possibility of offering better predictions regarding short-term neurologic outcomes and tailored management in newborns treated by TH.

Between January 1989 and December 1991 614 arthroscopic subacromial decompressions were performed for impingement syndromes. The first 100 cases represented our learning curve. The first 74 of the remaining 514 cases were available for evaluation and form the basis of the results presented here. Twenty (27.02%) patients were rated stage II in Neer's classification and 54 (72.98%) were rated stage III, 33 (44.59%) of them with a small full-thickness tear (less than 1 cm) and 21 (28.37%) with larger defects. Patients were evaluated pre- and postoperatively utilizing the ULCA shoulder score. The average follow-up was 7.9 months. The overall results were satisfactory in 67 cases (90.5%) and unsatisfactory in 7 cases (9.5%). Within the satisfactory group, 28 results (37.8%) were rated excellent and 39 (52.7%) were rated good. In the unsatisfactory group four results (5.4%) were rated fair and three (4.1%) poor. The results in advanced stage III (n = 21), with an average follow-up of 8.4 months, were satisfactory in 20 cases (excellent in 8 and good in 12) and unsatisfactory in one case. It is concluded that arthroscopic subacromial decompression is an effective treatment for both stage II and III impingement syndromes, producing acceptable results that are comparable to those of open procedures. Technically, it seems necessary to perform synovectomy of the ventral synovia in the glenohumeral joint, to resect the coracoacromial ligament completely and also to remove calcifications completely. Depending on the findings of a preoperative sonographic examination of the shoulder joint, the extent of the acromioplasty may be minimized.

The fatigue response of PMMA-specimen was tested under cyclic bending of 1.5 Hz in a particularly designed testing device. Specimen were tested that a "Wöhler" curve and the corresponding fatigue strength could be evaluated. The fatigue strength was reached after a comparatively short time and ranged in the order of 33 per cent of static breaking strength.