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The detailed study of the temperature dependence of the viscosity of (Co,Fe){(Si,B) amorphous metallic alloys up to crystallization temperatures was carried out. The kinetics of the non-equilibrium viscosity was described using Vogel{Fulcher{Tammann law below the glass transition temperature.

are determined by the static pinning potential E0(x) (x is a DW displacement). The magnetic after-efiect (MAE) of permeability „ = „1 i i„2 is related to the stabilization potential ES(x;t) = ES(x)G(t), separated to ES(x) = 1 fix 2 , for small x < d (d is a DW thickness) and to time relaxation function G(t), when an external magnetic fleld H(t) = H0 exp(i!t) with small amplitude H0 < Hcr is applied. The MAE of the complex permeability „ can be expressed as a change of its reciprocal value (reluctivity) r = 1=„ = r1 + ir2: ¢r(t) = r(t2) i r(t1) at time interval from t1 to t2 after demagnetization [1].

We have investigated the influence of the addition of different transition metals (Fe. Co. Cr. Mn. Mo. Ni. Os. Pt. Ru. Ta. Ti. V and W) on the time-temperature stability of amorphous Fe 80 TM 3 B 1- alloys. Time stability is represented by the Magnetic After - Effect (MAE). Each element influences near neighbourhood of other atoms by its characteristic way which results in a different chracteristics of the MAE spectra and its spectra of activation energies. It turned out from our measurements that samples can be divided into the three groups: The first one contains alloys with MAE similar to that of an FeB alloy, in the second there are alloys with different MAE, and in the third one there are alloys with almost no MAE. It was found that MAE can be successfuily descnbed on the basis of the micromagnetic model with activation parameters Q * = 1.3 - 1.7 eV and τ 0 = 10 -18 -10 -13 S. Small values of the preexponantial factor points out that MAE in Fe 80 TM 3 B 17 amorphous alloys is caused by the rearrangement of the mobile atom pairs within the domain walls.

We have investigated the influence of chromium on the magnetic after-effect (MAE) of amorphous Fe 85 − x Cr x B 15 ( x = 0, 2, 3, 5 and 7) alloys. Isochronal curves were obtained for times t = 5, 10, 30, 60, 120 and 180 s in the temperature interval from 77 K up to T c . A computer analysis was performed to evaluate the spectra of activation energies from these measurements. The spectra of activation energies have a characteristic shape with a peak at the value of 1.2–1.4 eV. The pre-exponential factors are found to lie between 4 × 10 −13 and 1.1 × 10 −17 s. This indicates that the MAE can be assigned to short range atomic reorientation near free volumes. It follows from the isochronal MAE measurements that the addition of Cr atoms also causes a decrease in MAE amplitude as well as a decrease in Curie temperature. The higher the Cr-contents, the lower the MAE and the preexponential factor τ 0 .

To define the role of ultrasonography in the diagnostic algorithm for patients with shoulder joint injury and to show its potential for the detection of rotator cuff tears and Hill-Sachs lesions.A group of 52 patients with clinical signs of shoulder disorders following trauma who were treated in the 2005-2006 period. After ultrasonographic examination, all patients were surgically treated by arthroscopy. In 12 of them an additional magnetic resonance imaging was carried out before surgery. The results of ultrasonography were compared with arthroscopic findings in terms of detection of full-thickness rotator cuff tears and Hill-Sachs lesions. These were the two most frequent traumatic lesions detected by ultrasonography.A full-thickness tear of the rotator cuff was correctly diagnosed in 13 patients. In further four the ultrasound finding was incorrectly interpreted as a moderate rotator cuff injury. For the detection of full-thickness tears, the sensitivity of the method was 76 %, its specificity was 94 % and accuracy 88 %. The detection of Hill-Sachs lesions by ultrasonography correlated with arthroscopic findings, with a sensitivity of 86 %, specificity of 93 % and accuracy of 92 %.A number of studies report on options for the ultrasonographic detection of various types of traumatic injury to shoulder structures. Examination by ultrasound shows skeletal surfaces, thus permitting detection of a minor bone injury or a Hill- Sachs defect, and reveals soft tissue shoulder structures including tendons, ligaments and bursae. In some studies the possibility of detecting rotator cuff tears by ultrasonography has been described. Although sufficient accuracy of ultrasonographic examination in this region is reported, the results are not consistent.Our results show high reliability of ultrasonography for the diagnosis of shoulder trauma. The detection of full-thickness rotator cuff tears and Hill-Sachs lesions was possible with sufficient accuracy, which makes this quick, simple and available examination a valuable diagnostic tool. The finding of a rotator cuff tear is important information for the orthopaedist and, in the majority of patients, is also an indication for surgery. An ultrasonographic examination can therefore be regarded as a standard part of the diagnostic algorithm for shoulder trauma.

In our work we have investigated magnetic after-effect (MAE) of complex permeability (μ = μ 1 − jμ 2 ) in nearly non-magne-tostrictive ferromagnetic alloys CoFeCrSiB. MAE is represented by a relative change of both real ( r 1 ) and imaginary ( r 2 ) parts of the complex reluctivity Δ/( = 1/(#x003BC; − 1)) which may be expressed as follows: Δr 1 (t)/r 1 = r 1 (t) − r 1 (t 1 )/r 1 (t 1 ), Δr 2 (t)/r 2 = r 2 (t) − r 2 (t 1 )/r 2 (t 1 ) Time t 1 was 0.9 s for each measurement. Temperature dependences of both real (μ 1 ) and imaginary (μ 1 ) parts of complex permeability were measured in the temperature interval from − 175 to 100 °C. Computer analysis was made to evaluate the spectra of activation energies connected with MAEs. It was found that the MAE spectrum with a maximum at about 100 °C corresponds to the spectrum of activation energies with the most probable value 1.1 eV and τ 0 = 5.10 −15 s.

The authors present a group of 6 patients treated in 1996-2000 with giant "impossible" hernia the contents of which "lost their rights in the abdominal cavity". The patients involved were old polymorbid people (mean age 75 years), 5 suffered from acute, one from chronic obstruction of the gut. After intensive preparation the authors implemented a hernioplasty, using an excessive surgical mesh, reduced the volume of the abdominal contents by the omentum in all subjects, by the right colon in two and by a 0.5-1 m segment of the ileum in 3 patients. Only one extremely polymorbid patient died because of multiorgan failure on the 17th day after surgery. In 5 patients artificial ventilation was necessary from 2 hours to 17 days. As to complications, diarrhoea was recorded in one patient and infection of the mesh in another one. The authors conclude that the majority of "impossible" incarcerated hernias can be resolved by visceroreduction and enlargement of the volume of the abdominal cavity by inserting an excessive surgical mesh into the enlarged hernial neck. In elective operations of such hernias for the preparation forced reduction of the weight can be used and the technique of enlargement of the abdominal volume by intermittent pneumoperitoneum. In this way a giant "impossible" hernia can be treated without threatening the patient's life by cardiopulmonary failure.

We have investigated the magnetic after-effects (MAEs) of the real and imaginary parts of the ac inverse permeability r [ r (t) ≡ 1/ μ = r 1 (t) + j r 2 (t) ]. For a near-zero magnetostrictive CoFeCrSiB amorphous alloy, it was found that r 1 ( t ) after demagnetization increases, whereas r 2 ( t ) mostly decreases. The activation energy spectra which control the MAE 1 and MAE 2 of r 1 ( t ) and r 2 ( t ), respectively, show different distributions p 1 ( Q ) and p 2 ( Q ) in the range 0.72–1.1 eV, with maxima at 0.78 eV ( τ 0 = 3.6 × 10 −14 s).

Results of the magnetic relaxation in the amorphous structure of Co 100− x B x ( x = 21–30 at%) alloys obtained by magnetic aftereffect (MAE) measurements are presented. Long-time experiments were performed at temperatures 300–450 K. MAE isotherms were analyzed in the frame of the fractal model. Parameters of non-Debye processes were obtained separately for shorter and longer times. It was found that the characteristic exponent β 1 = (0.42–0.52) for shorter times and β 2 = (0.16–0.24) for longer times.

In the work presented, we have investigated temperature dependences of the relative permeability and the relative resistivity of amorphous FeZrCuB alloys with increasing and decreasing temperatures in the range 50–600 °C. Curie and crystallization temperatures were estimated from the analysis of measured dependences. The spectra of magnetic after-effect (MAE) were measured in the temperature range ( − 100 °C, T c ). Two maxima in the relaxation spectra have occurred at the temperatures − 30 and 70 °C. The first maximum corresponds with the magnetic relaxation and the second corresponds with magnetic after-effect induced by phase transition. The spectrum of activation energy of magnetic relaxation was found by computer analysis. The most probable value of the activation energy is 1.25 eV. In this work, we have also studied microstructures of samples annealed near the crystallization temperature.

A set of amorphous Finemet based ribbons of the composition Fe 735-x Ni x Nb 3 Cu 1 Si 13.5 B 9 (0≤x≤25) was produced by melt spinning technique. For determining the critical temperatures DSC studies as wel as acsusceptibility measurements were performed. Additionally pinning field and MAE (magnetic after -effect) studies were made. After a heat treatment at 550°C for 1h a nanocrystalline state was formed which leads to a magnetic softening for Ni concentrations up to x=15. The first crystallization temperature at about 545 °C is nearly independent of the Ni concentration. The second crystallization stage decreases from 695°C (for x=0) to 588 °C (for x=25°C).