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Paragangliomas of the head and neck region are rare and predominantly asymptomatic tumors. These neoplasms arise from widely distributed paraganglionic cells, which originate from both mesodermal elements of third branchial arch and the neural crest residues. Despite the rare occurrence of paragangliomas, problems encountered in their diagnosis, unclear malignancy and treatment ensure that they still remain in the focus of head and neck surgeons. This is a retrospective study of the medical records of patients treated in the ENT Department of the 5th Military Hospital in Krakow during the period 2010-2014. All the preoperative, intraoperative and postoperative data were carefully analyzed for each patient. Thirteen patients (16 tumors) were treated during the study period. All the patients with a pre-operative suspicion of paraganglioma underwent computed tomography angiography. The whole cohort of patients was treated surgically. Paraganglioma should be always considered in the differential diagnosis for painless neck masses. These tumors require thorough radiological pre-operative evaluation and skilled operative technique. Surgical treatment occurs to provide good cure rates with minimal recurrence and morbidity rates.

Regenerating oak seedlings by different methods impacts taproot architecture, root-to-shoot allometry and, potentially, soil water use and plant growth under water limitations. In the present study, Quercus robur (L.) seedlings regenerated by four different methods – sowing (acorn-sown seedlings), sowing followed by shoot clipping (coppiced), sowing followed by root-pruning (root-pruned), and container planting with the root plug intact (containerized) – were subjected to four water-shortage regimes – full watering and 75, 50, and 25% of full watering. These treatments were used to test the hypotheses that root morphology, anatomy and biochemistry varied among regeneration methods, and, thus, differentially affected plant responses to water-shortages. For most traits, the response to water shortage of acorn-sown and containerized seedlings was similar, and opposite to that of coppiced and root-pruned seedlings. Water shortage did not change tree allocation to total root biomass among regeneration methods but altered the partitioning between absorptive and structural roots within the root system. Acorn-sown and containerized seedlings produced more pioneer roots, and coppiced and root–pruned seedlings more highly-branched fine roots with greater specific root length and specific root surface area under greater water shortage. Thus, acorn-sown and containerized oaks appeared to be primed for water foraging, and coppiced and root-pruned oaks for water absorption efficiency in response to water shortage. Water shortage caused a reduction in nonstructural carbohydrate concentrations in fine roots of acorn-sown and containerized seedlings and in the taproot of coppiced and root-pruned seedlings. Results generally indicated that seedling response to water limitation depended on the regeneration method, highlighting the importance of root–to–shoot allometry, taproot development, and carbon reserve mobilization for plant functioning under water shortage. Acorn-sown and containerized oaks seedlings might be more suitable for forest regeneration in sites characterized by severe water shortage periods. The reduction of taproot starch reserves under strong water shortage may render root-pruned oak trees more susceptible to topsoil water deficit than acorn-sown trees. This work contributes to understand drought acclimation and to identify the most adequate forestry regeneration practices to adapt forest ecosystems to ongoing climatic changes.

During the Future Advanced Rotorcraft Drive System (FARDS) program, the Aviation Development Directorate (ADD), Aviation Applied Technology Directorate (AATD), Bell Helicopter Textron Inc., University of Toledo and the Aristotle University of Thessaloniki worked together to perform bearing coating tests. The mechanical properties of the DLC coating and its steel substrate were determined via nano-indentations and a FEM supported evaluation of the obtained results. The coating fatigue and adhesion were quantified by perpendicular and inclined impact tests respectively, coupled with appropriate finite element method (FEM) calculations. The inclined impact tests were conducted under lubricated conditions for avoiding abrasion caused by sliding friction on the coated surfaces. In this way, the coating fatigue failure during this test was mainly affected by the impact load, the material's properties and the film adhesion. The effects of these factors on the coating fatigue failure were described via an iterative FEM supported method. Using this method, the coating adhesion was estimated taking into account the exercised impact loads and the determined material properties.

Measurements of cardiac marker proteins in plasma from patients with acute myocardial infarction (AMI) have become important in the evaluation of recanalization therapy. The validity of this approach has however been questioned, because it was claimed that coronary reperfusion may increase the recovery in plasma of cardiac enzymes, such as creatine kinase (CK). In the present study, possible effects of thrombolytic therapy on the release of enzymatic and nonenzymatic marker proteins were investigated. Activities of CK and lactate dehydrogenase (LDH), and concentrations of myoglobin (Mb) and fatty acid-binding protein (FABP) were determined in serial plasma samples obtained from 50 patients with confirmed AMI, of whom 36 received thrombolytic therapy, and 14 did not. Treatment delay was 2.8+/-1.6 (mean+/-SD) h, and hospital delay in untreated patients was 2.7+/-1.8 h. Average infarct size, expressed in gram-equivalents of heart muscle per litre of plasma (g-eq/l), varied between 5.5 and 7.2 g-eq/l for the four marker proteins in patients treated with thrombolytic therapy, and between 4.6 and 6.4 g-eq/l in untreated patients, with a tendency to larger infarct sizes for Mb and FABP than for CK and LDH. Thrombolytic therapy, although significantly accelerating protein release rates, did not influence the release ratios. These results indicate that thrombolytic therapy has no significant effects on the recovery of cardiac marker proteins in plasma.

Room temperature magnetostriction in spherically shaped single crystals (Y 2- x Nd x )Fe 14 B (where x = 0, 0.25) and aligned MnAIC(Ni) magnet has been measured by means of the three-terminal capacitance method. The measurements were performed on magnetically unsaturated samples, in order to determine saturation magnetostriction constants. A theoretical model of rotational magnetization has been developed.

The temperature distribution in sections normal and parallel to the growth directions of three copper plates separated by graphite and grown together by the Bridgman method were calculated. Computer calculations predict the isotherm curvatures at the interface across the thickness of the plates during crystal growth.

Single crystals of Y2(Co,M)17 compounds grown at different growth rates were characterized by metallographic and Bitter pattern observations which inform about the microstructure and the magnetic domain structure of the crystals and by magnetization curves. The study shows the correlation between the growth conditions and the structural quality of the grown single crystals.

The temperature fields in large single crystal plates of copper and aluminum grown by the Bridgman method were calculated. A mathematical method based on thermal balance was used for computer calculations of the isotherms. The observation of different shapes of the interface made the analysis of the calculated isotherms during crystal growth possible.

Stability of the temperature of the furnace, Tf, is an important factor in growing crystals of high quality. Calculations have shown how sensitive is the solid-liquid interface in a large metal charge during Bridgman growth to introduced changes of this temperature.

Neutron rocking curves in reflection and in transmission have been measured for several copper single crystal plates. A characteristic feature of as-grown plates is a decrease in peak intensity, measured for the succeeding parts of the plate in the direction of crystal growth. The as-grown plate is thought to be composed of a central part of small mosaic spread and the outer layers of increased mosaic spread, with different sizes of mosaic blocks along the crystal plate.

The suppression of striations formed during Bridgman growth has been achieved by using low initial temperatures of the melt for crystals of copper, nickel, Ni-Fe and Co-Fe alloys. In the case of lead it has been shown also that the low initial temperature of the melt and not the cooling rate of the crystal is responsible for the suppression of striations. The effect of preferred crystallographic orientation factor on the distribution of the striations in different crystals has been noted and discussed.

Large single crystals of Ni, Co- 8 at % Fe and Ni-Fe alloys were used to study the position of the rotation axis of mutually misoriented subgrains of the striation type substructure. In contrast to aluminum, no correlation was observed between the position of the rotation axes and the crystal axis (growth direction); in contrast to zinc, no evident correlation between the position of rotation axes and any crystallographic direction was found. However, rotation axes tended to lie near to the corresponding subboundaries. Misorientation angles across subboundaries reach several (6–7) degrees of arc. In some crystals, light and dark cross bands are observed. Striation lines change the direction in successive bands. They are parallel to the crystal axis in light bands and tend toward a given crystallographic direction in the dark ones.