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The structure of a convective flow of molten magnesium in a metallothermic titanium reduction apparatus has been studied numerically for various retort heating and cooling configurations. The mathematical model is based on the thermogravitational convection equations for a singlephase fluid in the Boussinesq approximation. A nonuniform computational grid with a total of 5 million grid points was used. The LES (Large Eddy Simulation) technique was applied to take into account the turbulence. The problem was considered in a three-dimensional nonstationary formulation, which allowed one to construct the instantaneous and average characteristics of the process and to analyze the velocity and temperature pulsation fields. It has been found that steady axisymmetric flows occur at moderate Grashof numbers (Gr ~ 107–108), while unsteady turbulent flows take place at Grashof numbers corresponding to the actual titanium reduction process (Gr ~ 1012). The influence of the degree of nonhomogeneity of the heat release due to the titanium reduction reaction that runs mainly on the magnesium surface has been studied. The computations have been performed for two configurations of the system for maintaining the apparatus heating regime: with furnace heaters operating at full power and with switched-off furnace heaters. Fundamental differences in convective flow structure for these two heating methods have been revealed. It has been established that the most intense velocity and temperature pulsations arise in the region adjacent to the interface between the cooled and heated parts of the retort side surface.

The advantages that wavelet analysis (WA) provides for resolving the structures in experimental data are demonstrated. Due to good scaling properties of the wavelets, one can consider data with various resolutions, which allows the resonances to be separated from the background and from each other. The WA is much less sensitive to noise than any other analysis and allows the role of statistical errors to be substantially reduced. The WA is applied to the e+e− annihilation into hadron states with quantum numbers of ρ and ω mesons, and to p-wave ππ scattering. Distinguishing the resonance structures from an experimental noise and the background allows us to make more reliable conclusions about the ρ′ and ω′ states. The WA yields a useful set of starting conditions for analysis of ω′ states with the multiresonance Breit-Wigner method preserving unitarity in the case of overlapping resonances. We also apply the WA for the ratio \(R_{e^ + e^ - } \).

A simple model for a multiscaled MHD dynamo is suggested. The uppermost tier of the model controls the evolution of the large-scale magnetic field, while the lower tiers are responsible for the evolution of the small-scale velocity and magnetic fields. This approach makes it possible to reproduce, e.g., the evolution of the Galactic magnetic field for realistic magnetic Reynolds numbers, which cannot be done using direct, detailed simulations.

We demonstrate the advantages of the wavelet analysis (WA) for resolving the structures in experimental data on e + e - annihilation into hadron states with quantum numbers of $\omega$ meson. The WA yields a useful set of starting conditions for analysis of $\omega'$ states with multiresonance unitary Breit-Wigner method. We also apply the WA for the ratio R e+e- .

The shell model of developed convective turbulence of an incompressible fluid is considered. Regimes developing at high Rayleigh numbers are investigated numerically for three- and two-dimensional motion. It is shown that in the three-dimensional turbulent convection model the inertial Obukhov-Bolgiano interval is developed on large scales, but this interval is unstable and gives way to the Kolmogorov regime in which the temperature behaves as a passive admixture. In the two-dimensional turbulent convection model a finite scale interval on which the buoyancy forces determine the nature of the fluctuations but the spectral laws established differ from those that follow from dimensional considerations for the Obukhov-Bolgiano interval is detected.

The very earliest studies of the peculiarities of developed turbulence in a medium with an inhomogeneous density, attributed to the essential influence of buoyancy forces on the inertial range dynamics, have been carried out by Obukhov [1] and Bolgiano [2]. Obukhov established the existence of a boundary scale l B , above which the input of kinetic energy by buoyancy forces is essential in comparison with the Kolmogorov spectral flux. Bolgiano studied turbulence in a medium with a stable stratification, when the kinetic energy was transformed into the potential, and derived, by performing the dimensional analysis, the spectral laws for kinetic energy and energy of fluctuations of temperature, (E υ (k) ~ k -11/5 and E t (k) ~ k -7/5).

Twenty-four thrombocytopenic patients refractory to random-donor platelet support were given 106 platelet transfusions obtained from 57 different HLA-typed single donors. For critical evaluation of the transfusion responses, “fullhouse” HLA typing of donors and a precise measurement of the number of infused platelets were performed. Posttransfusion platelet increments were related to the HLA matching of donor-recipient pairs and to leukocyte crossmatch tests in vitro. The transfusion response displayed a striking difference depending on the absence (type-0 match) or presence (type-1 or-2 match) of donor HLA antigens differing from the recipient. Whereas 95% of transfusions from type-0 match donors resulted in a compatible platelet increment, only 20% successful transfusion responses could be achieved with type-1 or -2 match donors. In 77% of type-1 or -2 match transfusions with poor posttransfusion platelet increments, the lymphocyte cytotoxicity test (incubation time 180 min at room temperature) was positive. This test therefore seems to be a useful tool in predicting the outcome of transfusion responses in type-1 and -2 match pairs. In contrast, the lymphocyte cytotoxicity tests were of no predictive value in type-0 match pairs. The influence of specific antigranulocyte antibodies on type-0 match platelet transfusions was assessed in four recipients. Although severe transfusion reactions were observed, no detrimental influence on platelet increments could be observed, at least following the initial transfusion.

A 26-year-old man with severe aplastic anemia was treated with high-dose Cyclophosphamide followed by the infusion of bone marrow cells from his HLA-identical sister. After initial intake of the graft, rejection ensued by day 46 which was followed by a permanent complete aplasia. After 4 months, bone marrow retransplantation with the same donor was attempted after a more intensive conditioning regimen. This led to permanent engraftment with rapid normalization of the blood counts lasting now for over 12 months. The patient has since remained in excellent clinical condition without signs of graft-versus-host disease.

A randomized study was performed in 54 thrombocytopenic patients with acute leukemia. Alloimmunization of recipients of random multiple-donor platelet concentrates (MD group) was compared to that of patients receiving random single-donor platelets (SD group). In the SD patients, formation of alloantibodies (mostly anti-HLA) occurred less frequently (p less than 0.002), after a longer time period (p less than 0.002), and after a higher number of transfusions (p less than 0.005) as compared to MD patients. SD patients also became refractory to random platelets less frequently (p less than 0.005), after a longer time period, and after a higher number of transfusions (p less than 0.02). In SD patients, the increments after the first and the last transfusion were in the same range, whereas in MD patients, the 1-hr (p less than 0.001) and the 24-hr (p less than 0.025) increments decreased from the first to the last transfusion. Thus, the use of random SD platelet transfusions postponed alloimmunization.

A 17-year-old woman with severe aplastic anemia was treated with high-dose cyclophosphamide followed by infusion of bone marrow cells from her HLA-identical, ABO-incompatible brother. The marrow graft failed to take. Subsequently, the patient revealed an autologous marrow reconstitution leading to a near-complete hematologic recovery which is now persisting for over 20 months.

In a patient with generalized prostatic carcinoma and hypofibrinogenaemia heparin infusion on four occasions abolished systemic fibrinolysis as determined by euglobulin clot lysis time, bovine fibrin plate assay, thromboelastography, and immunoelectrophoretic demonstration of fibrinogen split products. The pathogenesis of hypofibrinogenaemia in cases of prostatic carcinoma and the possibility of a direct heparin effect on fibrinolysis are discussed. Despite the lack of histological evidence for intravascular coagulation, the findings are considered additional evidence for the view that fibrinolysis in this syndrome may be secondary to intravascular coagulation.

1. Die Erythrocyten-Uberlebensdauer von 27 nicht ausgewahlten Patienten mit Leberkrankheiten wurde mit der Radiochrom-Methode untersucht: 17 Falle mit akuter Hepatitis, 5 Falle mit akuten Schuben einer vorbestehenden chronischen Hepatitis und, zum Vergleich, 5 Falle mit Cirrhose. Die Ergebnisse wurden mit dem klinischen Verlauf und den Hamoglobin- und Reticulocyten-Werten verglichen. 2. Bei 9 der 17 Falle von akuter Hepatitis war ein leichter bis mittelschwerer Grad von Hamolyse nachweisbar; nur in einem Fall war die Hamolyse betrachtlich (T 1/2 von 15 Tagen). Bei allen Patienten war der hamolytische Prozes kompensiert. Meistens bestand eine leichte Reticulocytose. Die hamolytische Episode bei akuter Hepatitis ist von kurzer Dauer und verlauft klinisch fast immer inapperzept. Die unklare Pathogenese wird diskutiert. 3. Bei 4 der 5 Falle von akutem Schub einer chronischen Hepatitis und bei allen 5 Cirrhosen lag eine mittelschwere bis schwere Hamolyse vor. Bei diesen Fallen bestand eine Splenomegalie und die Cr51-Oberflachenmessungen ergaben zum Teil erhohte Radioaktivitat uber der Milz als Ausdruck der splenogenen Hypersequestrierung der Erythrocyten. 4. Aus dieser Untersuchung geht hervor, das bei floriden chronischen Hepatitisformen und progressiven Cirrhosen eine manifeste hamolytische Anamie und bei den meisten Fallen von akuter Hepatitis ein nur kurzdauerndes, klinisch nicht manifestes hamolytisches Syndrom vorliegt.

Hypokalaemia and metabolic alkalosis were seen in three patients and additionally hypernatraemia in two patients treated with 100 mega units of sodium penicillin G for subacute bacterial endocarditis. The hypernatraemia was probably due to the administration of insufficient fluid, while urinary potassium loss was an important factor in producing hypokalaemia and metabolic alkalosis after. Penicillin may promote urinary potassium excretion by acting as a non-reabsorbable anion.Potassium depletion during treatment with massive doses of sodium penicillin G may be prevented by concurrently administering potassium-sparing diuretics or by using the potassium salt of penicillin.

A material of 87 patients who underwent cardiac surgery for active infective endocarditis from 1975 to 1987 is analyzed retrospectively. 91 emergency operations were performed in 19 women and 68 men with a mean age of 48 years. 72 native valves and 19 prosthetic valves were involved. Streptococci (41%) and staphylococci (27%) were the most frequent bacteriological isolates, whereas 19% of the cultures remained negative. Heart failure (52%), embolism (21%), uncontrolled infection (11%), prosthetic valve endocarditis (10%), atrioventricular block (4%) and ventricular septal defect (2%) were the indications for surgery an average of 22 days after diagnosis. 17 patients (19%) died, 9 during hospitalization from heart failure or septicemia and 8 in the later course. 16 patients required reoperation for valvular incompetence (5), paravalvular leak (4) or prosthesis infection (7). Five relapses (5.5%) and two reinfections (2.5%) were treated surgically while two reinfections responded to medical therapy alone. Postoperatively, 34 patients (39%) suffered severe complications such as neurological deficits, prosthetic valve endocarditis or anticoagulant haemorrhage. After a mean observation period of 52 months (range 1-147 months) 64 (91%) of the surviving patients were in NYHA classes I + II and 6 (9%) in NYHA classes III + IV.

A randomized study was performed in 54 thrombocytopenic patients with acute leukemia. Alloimmunization of recipients of random multiple-donor platelet concentrates (MD group) was compared to that of patients receiving random single-donor platelets (SD group). In the SD patients, formation of alloantibodies (mostly anti-HLA) occurred less frequently (p less than 0.002), after a longer time period (p less than 0.002), and after a higher number of transfusions (p less than 0.005) as compared to MD patients. SD patients also became refractory to random platelets less frequently (p less than 0.005), after a longer time period, and after a higher number of transfusions (p less than 0.02). In SD patients, the increments after the first and the last transfusion were in the same range, whereas in MD patients, the 1-hr (p less than 0.001) and the 24-hr (p less than 0.025) increments decreased from the first to the last transfusion. Thus, the use of random SD platelet transfusions postponed alloimmunization.

Seven cases of agranulocytosis and two of liver damage that were probably due to amodiaquine treatment were studied. In five cases agranulocytosis was combined with liver damage, and in one case of primary liver damage moderate neutropenia was present. Three patients died. High total doses or prolonged duration of treatment, or both, appear to favour the occurrence of these reactions. The clustering of five of the seven cases of agranulocytosis within six months in one medical centre indicates that the risk to benefit ratio of amodiaquine for malaria prophylaxis should be re-evaluated.

Two patients with polycythemia vera received intravenously an accidental tenfold overdosage of radiophosphorus therapy (60 and 50 mCi 32P, respectively). In both patients, the occurrence of hemorrhagic complications 3 wk after the 32P medication led to detection of the error and referral to our hospital. Upon admission they showed an agranulocytosis, severe thrombocytopenia, and bone marrow aplasia. In both cases, spontaneous recovery of the hematopoiesis was observed from day 40 posttreatment onward. In one patient, a slow but ultimately complete normalization of blood counts and marrow morphology took place, whereas in the other, a mild thrombocytopenia persists. Nearly 5 yr after the accidental overdosage, both patients are clinically well. Symptoms of polycythemia vera have not reappeared up to now. Attempts were made to evaluate the radiation dose absorbed by the bone marrow. In the first patient, the daily 32P excretion was determined from day 22 to day 60, whereas in the other patient a whole body count was performed on day 78 after administration. From these results, an approximate cumulative bone marrow dose of 10 Sv (1000 rem) could be calculated.

A short review is presented of the primary and the secondary types of therapy-refractory anemia. Special emphasis is placed on the newest results obtained with therapeutic plasmapheresis and with recombinant human erythropoietin.

A female patient is described who developed skin and subcutaneous fat necrosis on two occasions after intake of acenocoumarol. Several months later identical skin changes occurred during an episode of cholestasis associated with a prolongation of the prothrombin time to an extent comparable with therapeutic anticoagulation; intake of oral anticoagulants could be excluded. This association gives new insights in the pathogenetic mechanisms responsible for the so-called coumarin necrosis and indicates that it may be not due to drug toxicity or allergy.

Clinical and serological data in 5 cases of autoimmune hemolysis following therapy with Catergen are reported and compared to the data in similar literature reports. The main argument in favour of Catergen as causative agent in our 5 cases was rapid remission of hemolysis within 2 1/2 to 10 weeks of withdrawing Catergen treatment. Besides causing hemolysis mediated by drug dependent antibodies, long term treatment with Catergen may induce formation of IgG autoantibodies against red blood cells with or without overt hemolysis.

In two randomized double-blind studies perioperative bleeding complications and thromboembolic events were assessed in 189 patients (pts) undergoing elective visceral surgery after subcutaneous administration of a low molecular weight (LMW) heparin fragment (KABI fragment 2165) or unfractionated (UF) heparin. The first study comparing 1 X 7'500 anti-factor Xa IU LMW heparin daily with 2 X 5'000 IU UF heparin was interrupted because of excessive bleeding complications (LMW heparin: 11/23 pts, UF heparin: 2/20 pts, p less than 0.01). In the second study (146 pts) the dose of LMW heparin was reduced to 1 X 2'500 anti-factor Xa IU. Bleeding complications (LMW heparin: 14.9%, UF heparin: 15.3%) and thromboembolic events (LMW heparin: 2.86%, UF heparin: 2.94%) were equal among the two groups. 2'500 anti-factor Xa IU/day of this LMW heparin fragment, corresponding to 15 mg/day, is the lowest dose of a LMW heparin used in a randomized clinical trial and was found to be a safe and efficient regimen in perioperative thrombosis prophylaxis. An advantage of LMW heparin over UF heparin is its once daily administration.