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Abstract  The hybrid cellular automaton (HCA) algorithm was inspired by the structural adaptation of bones to their ever changing mechanical environment. This methodology has been shown to be an effective topology synthesis tool. In previous work, it has been observed that the convergence of the HCA methodology is affected by parameters of the algorithm. As a result, questions have been raised regarding the conditions by which HCA converges to an optimal design. The objective of this investigation is to examine the conditions that guarantee convergence to a Karush-Kuhn-Tucker (KKT) point. In this paper, it is shown that the HCA algorithm is a fixed point iterative scheme and the previously reported KKT optimality conditions are corrected. To demonstrate the convergence properties of the HCA algorithm, a simple cantilevered beam example is utilized. Plots of the spectral radius for projections of the design space are used to show regions of guaranteed convergence. [ABSTRACT FROM AUTHOR]

Purpose: Contemporary total knee arthroplasty femoral component designs offer various degrees of fit amongst the global population. The purpose of this study was to assess component fit of contemporary femoral component design families against multiple ethnicities., Methods: Using a multi-ethnic dataset including Caucasian, Indian, and Korean subjects, this study investigated component fit in six contemporary femoral component design families (A: Persona™, B: NexGen (®), C: Sigma (®), D: GENESIS™ II, E: Triathlon (®), F: Vanguard (®)). Component overhang/underhang was measured between the resected distal femur and its corresponding component size and compared across design families and ethnicities. The severity of overhang/underhang and propensity of downsizing due to clinically significant overhang were quantified for the overall dataset and each ethnicity., Results: In all the overhang cases, Designs A and B had significantly lower component overhang than the other designs (p < 0.02). In all the underhang cases, Designs C and E had significantly greater underhang than the other designs (p < 0.01). Component design influenced the occurrence (% bones) of component downsizing due to clinically significant overhang (>3 mm), with the highest incidence observed in Designs D (20.5%) and F (17.7%), and the lowest incidence observed in Designs A (0%) and B (0.4%). Variation in component fit was significantly impacted by designs (p < 0.01) but not ethnicities (n.s.)., Conclusions: The inclusion of multiple ML/AP shape offerings and the increased number of available sizes in Design A, as compared to other contemporary femoral component design families studied, result in improved femoral component fit across various ethnicities.

Aim: To investigate the influence of unfractionated heparin on heparin-induced thrombocytopenia (HIT) type II., Patients and Method: In 162 patients with internal diseases treated therapeutically of prophylactically with unfractionated heparin (heparin sodium, heparin calcium), we carried out a prospective study to determine the incidence of HIT type I and II. 55.6% of the patients were female (n = 90) with an average age of 76.5 years (range: 25 to 96 years) and 44.4% male (n = 72) with an average age of 67.5 years (range: 17 to 93 years). A platelet count was taken regularly before the start of heparin treatment, on the first day of treatment and then every second day from day 5 to 20. Whenever HIT II was suspected, an HIPA test was performed., Result: Type I HIT occurred in 10%, type II in 3% of the cases. Two of the 5 patients with type II developed severe thrombotic complications., Conclusion: In view of the high incidence of HIT, regular platelet counts should always be carried out in patients receiving heparin treatment.

In 318 patients (155 men, 163 women) with an average age of 58.8 years (range 16-97 years), a retrospective study was carried out to determine the incidence of occult malignancies in patients with deep venous thrombosis affecting the pelvis and lower limb, confirmed by phlebography or duplex ultrasonography. It was found that, overall, 7.5% of all patients had occult malignant diseases, the most common being bronchial carcinoma (16%), colonic and renal carcinomas (12% each), and prostatic and pancreatic carcinoma (8% each). Of the patients with occult malignancy, 88% were older than 55 years. This fact shows that acute phlebothromboses may be a paraneoplastic early syndrome more often than was previously thought, and that patients older than 50 should always be screened for the presence of a tumor.

Background: The diagnosis of thromboangiitis obliterans may be difficult to establish in the everyday clinical setting., Patients and Methods: In 16 patients with thromboangiitis obliterans vital capillary microscopy was carried out on the nailfold on all ten digits. The longest visible capillary length was noted. As controls we employed 86 healthy subjects., Results: The measurement of the respective longest visible capillary on the nailfold revealed a visible capillary length of more than 0.6 mm in 38% of all patients with thromboangiitis obliterans (n = 16), such capillary lengths were not to be found among healthy subjects (n = 86)., Conclusions: Vital capillary microscopic determination of the visible capillary length is a simple-to-perform, non-invasive examination, which can help to establish the diagnosis.