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Part 1 of the article presents the technological path of producing semi-finished products for wires constituting input material in additive technologies. On the basis of the developed chemical compositions of experimental Fe-based alloys, laboratory ingots with a square section of 120×120 mm / 130×130 mm were produced, which were then hot rolled into flat bars. In order to select the physical parameters of the drawing tests, numerical modelling of the process was performed. As a result of the simulations, it was found that the calculated drawing force exceeds the capabilities of the experimental drawing machine and for this reason, hydrostatic extrusion was used to produce bars intended for drawing wires. The hydrostatic extrusion method was used to make bars with a diameter of 5 mm from three tested materials, while three experimental steels showed insufficient susceptibility to extrusion at high pressure and cracked at various strain values. An analysis of possible causes of bar breakage during extrusion was carried out on the basis of the results of microstructure examination.

The study presents an analysis of the influence of the plastic strain rate on the mechanical and structural properties of pure zinc. Thanks to the use of unconventional methods of plastic processing, the process of the equal channel angular pressing (ECAP) and the process of hydrostatic extrusion (HE), the tests were performed in a wide range of plastic strain rates, between 0.04 s−1 and 170 s−1. Plastic strain rate changes were carried out in the course of the significant plastic strain processes, and not on previously deformed samples. All tests were carried out at a constant value of plastic strain rate, ε ~ 2. A strong influence of the plastic strain rate on changes in the microstructure in zinc was observed during the tests. For the rates in the range of 0.04 s−1 to 0.53 s−1 its bimodal nature was observed, and in the range of 7 s−1 to 170 s−1 high homogeneity and evenness of grains related to the processes of continuous dynamic recrystallization was noticed. The effect of the strong homogenization of the microstructure was the increase in mechanical properties, yield point and tensile strength to the maximum values of UTS = 194 MPa, YS = 145 MPa at a strain rate of 170 s−1. Compared to the material with a bimodal microstructure, an over seven-fold increase in the elongation value was observed.

BackgroundNo single randomized study has ever before addressed the safety of On-Pump coronary artery bypass grafting (CABG) vs Off-Pump CABG in the setting of atrial fibrillation (AF) and data from small observational samples remain inconclusive.Methods and findingsProcedural data from KROK (Polish National Registry of Cardiac Surgery Procedures) were retrospectively collected. Of initial 188,972 patients undergoing CABG, 7,913 presented with baseline AF (76.0% men, mean age 69.1±8.2) and underwent CABG without concomitant valve surgery between 2006-2019 in 37 reference centers across Poland. Mean follow-up was 4.7±3.5 years (median 4.3 IQR 1.7-7.4). Cox proportional hazards models were used for computations. Of included patients, 3,681 underwent On-Pump- (46.52%) as compared to 4,232 (53.48%) who underwent Off-Pump CABG. Patients in the latter group less frequently were candidates for complete revascularization (PConclusionsOff-Pump CABG offered 30-day survival benefit to patients undergoing CABG surgery and presenting with underlying AF. On-Pump CABG was associated with significantly improved survival at long term.

Surgical ablation for atrial fibrillation (AF) performed at the time of other valvular- or nonvalvular cardiac procedure is a mainstay of therapy; yet the data regarding its influence on remote survival are sparse. We aimed to evaluate late survival in patients undergoing mitral valve (MV) surgery with concomitant surgical ablation for AF.Procedure-related data from the Polish National Registry of Cardiac Surgery Procedures (Krajowy Rejestr Operacji Kardiochirurgicznych) were retrospectively collected. A total of 11,381 patients with baseline AF (46.6% men; mean age 65.6 ± 9.0 years) undergoing MV surgery between 2006 and 2017 in 37 reference centers across Poland and included in the registry were analyzed. Median follow-up was 5 years (mean, 4.6 years; interquartile range, 1.9-7.9 years). Cox proportional hazards models were used for computations. Propensity score matching for the comparison of MV + ablation versus MV alone was performed.Of included patients, 2449 (21.5%) underwent surgical ablation for AF. Patients in this group were significantly younger (63.8 ± 8.7 years vs 66.1 ± 9.0 years; P .001) and were at lower baseline surgical risk (EuroSCORE, 2.86 vs 3.69; P .001). During the 12-year study period, there was a significant survival benefit (hazard ratio, 0.71; 95% confidence interval, 0.63-0.79; P .001) for MV + ablation compared with MV alone. After rigorous propensity matching (logit model, 1784 pairs) surgical ablation was associated with nearly 20% improved survival (hazard ratio, 0.82; 95% confidence interval, 0.70-0.96; P = .011). Benefit of surgical ablation was maintained in subgroup analyses, yet most benefit was appraised in low-risk patients such as those with EuroSCORE of 2 to 5 or age 50 years.Concomitant surgical ablation for AF in patients undergoing mitral valve procedures is safe, feasible, and significantly improves late survival.

Background: The hormonal metabolism of adipose tissue differs across regions of fat. This issue has never been verified in male patients with coronary artery disease (CAD) with and without systolic...

Iron deficiency (ID) may be an important, treatable co-morbidity complicating cardiovascular diseases, but considerable uncertainty exists about the diagnostic accuracy of blood tests. Accordingly, we investigated the relationship between blood tests for ID and iron stores in bone marrow aspirates, the diagnostic gold-standard for ID, in patients with stable coronary artery disease (CAD).Bone marrow aspirates were obtained from 65 patients with stable CAD undergoing cardiac surgery and 10 healthy controls. ID was defined as depleted extracellular iron stores (0-1 grade according to Gale scale) accompanied by ≤10% of erythroblasts containing iron.Bone marrow ID was found in 31 (48%) patients with CAD but in none of the controls (p0.01). Amongst patients with CAD, ID was present in 10 of 16 (63%) with and 21 of 49 (43%) without anaemia (p=0.17). The clinical profiles of patients with and without ID were similar. Of circulating biomarkers of ID, serum soluble transferrin receptor had the strongest association with bone marrow ID (area under curve: 0.876±0.048, 95% confidence interval: 0.762-0.948, for cut-off of ≥1.32mg/L-sensitivity: 67%, specificity: 97%).Almost half of patients with stable CAD have profound bone marrow iron depletion that can be accurately assessed non-invasively using serum soluble transferrin receptor.

Methods of exploitation drainage, which is presently applied in polish hard coal mines in Upper Silesian Coal Basin (Poland), are not effective enough, high risk of methane hazard can be observed, and production capacity of the mining plant is not fully used. Methane hazard, which may occur during planned coal exploitation, is presented in this paper. Following parameters are taken into consideration in the forecasts: coal extraction parameters, geological and mining conditions, deposit’s methane saturation degree and impact of coal exploitation on the degasification coefficient of the seams, which are under the influence of relaxation zone. This paper presents the results of the analysis aiming to verify applicability of drainage ahead of mining of the coal seams by using surface directional wells. Based on the collected data (coal seams’ structural maps, profiles of the exploratory wells, geological cross-sections), the lab tests of drilling cores and direct wells’ tests, static model of the deposit was constructed and suitable grid of directional wells from the surface was designed. Comparison of forecasted methane emission volume between the two methods is investigated. The results indicated the necessity of performing appropriate deposit’s stimulations in order to increase effectiveness of drainage ahead of mining. Keywords: Coal, Methane drainage, Methane hazard forecasting, Numerical modeling, Deposit simulation

Increasingly higher hard coal production capacity in Upper Silesian Coal Basin (Poland) in the last two decades led to significant increase of methane hazard occurrence in the workings of exploitation areas. An increase of methane content in the exploited seams and in the surrounding strata, associated with increasing depth of mining, results in higher methane emission into the longwall areas from exploited seams and degassing seams in the mining-induced de-stressed zone. Operational experience gained by the collieries confirms that reducing methane release during longwall operations often requires decreasing operating speed of a shearer in a shift. The paper presents an analysis of the parameters and factors, which have critical influence on the formation of methane hazard in longwall areas with high production capacity. Keywords: Methane hazard, Labour safety, Production capacity, Methane emission

A superior vena cava (SVC) aneurysm is an extremely rare case of vascular malformation in the chest cavity. This is a report of a case of a 57-year-old woman with a saccular SVC aneurysm which was 8 cm wide. The chest computed tomography (CT) scan confirmed a giant 75 mm × 79 mm × 81 mm mass containing the contrast medium from SVC, constricting the right lung parenchyma, narrowing the right innominate vein, in contact with the anterolateral chest cavity wall, and adjoining the superior mediastinum. Under general anesthesia and employing the median sternotomy approach, using a cardiopulmonary bypass (CPB), the venous aneurysm was successfully resected. The postoperative period was uneventful. Radical surgical resection using a sternotomy and a CPB is recommended.

Background: Commonly used cardiopulmonary bypass systems with cardiotomy reservoir, oxygenator, and roller pump require preoperative crystalloid filling. Radical reduction of the filling fluid volume and replacing it with the patient’s own blood has a fundamental impact on the outcome. Aim: A comparison of cardiopulmonary bypass filled with the patient’s blood, applied in Poland for the first time, and the classical system filled with crystalloids. Methods: Non-randomised trial in which patients undergoing coronary artery bypass grafting were divided into two groups: first operated on with use of cardiopulmonary bypass system with the patient’s own blood priming, and a control group operated on with standard technique. Levels of haemoglobin (HGB), haematocrit (HCT), platelets, leukocytes, creatinine, protein, C-reactive protein, procalcitonin, volume of transfused blood products, postoperative drain output, time to extubation, and consumption of catecholamines were compared. Results: The results of a study comparing the classical system with the blood-filled system (n = 60) showed a significantly smaller decrease in HGB and HCT levels (p = 0.001), resulting in reduction of blood product transfusions by 75% (p = 0.03). The new type of extracorporeal circulation reduced the total postoperative drain output by approximately 28% (p = 0.003). The systemic inflammatory response syndrome (SIRS) was less pronounced and the tissue perfusion was better due to smaller degree of haemodilution leading to better organ and heart protection. The patients required shorter mechanical ventilation times in the perioperative period. Conclusions: The use of a new system of cardiopulmonary bypass filled with the patient’s blood reduces the postoperative decrease in HGB and HCT, the amount of transfused blood products, and total postoperative drain output. It also shortens the time spent on mechanical ventilatory support.

Objective: Troponin T is a unique marker which might be particularly useful in assessing myocardial cell damage in patients undergoing cardiac surgery. The aim of the study was a comparison between intra-operative release of troponin T (TnT) during three different myocardial protection strategies. Methods: Thirty-eight PTS undergoing myocardial revascularization were randomised into 3 groups in whom procedure was performed with intermittent cross-clamp (Group I; na 13), beating-heart on pump without aortic cross-clamp (Group II; na 12), beating-heart without use of extracorporeal circulation (Group III; na 13). Serial venous blood samples were collected for TnT measurement prior surgery, 1, 4, 12, 24, 48, 72 h after the procedure. Haemodynamic measurements were made using a thermodilution PA catheter. Results: The groups were similar with respect to age, sex, preoperative LV function, number of grafts, potential risk factors. There were no hospital deaths and no myocardial infarction (MI) in three groups, postoperative haemodynamic measurements showed no significant differences. TnT serum levels were significantly higher in group I when compared to groups II and III. TnT levels were significantly lower in group III when compared to group II following 48-h post-operation. Conclusions: Coronary bypass grafting without aortic crossclamping and without CPB offers superior myocardial protection. q 1999 Elsevier Science B.V. All rights reserved.

We present a case of a 70 year-old woman operated due to severe mitral regurgitation. Early after surgery transthoracic echocardiography revealed the decreased effective orifice area of the implanted bioprosthetic valve and the stenotic features of transvalvular flow. Transesophageal echocardiography (TEE) disclosed a thrombotic cause of heterograft dysfunction. Due to the clinical deterioration and the unclear cause of prosthesis stenosis, the patient was reoperated. Intra-operatively bioprosthetic mitral valve thrombosis was confirmed. Precipitating factors of this rare complication including cardiac device related infective endocarditis (CDRIE) and the diagnostic applicability of TEE in this clinical scenario are discussed.

A pilot site for CO2 storage in coal seams was set-up in the Upper Silesian Coal Basin in Poland in the scope of the RECOPOL project, funded by the European Commission. About 760 tons CO2 were injected into the reservoir from August 2004 to June 2005. Breakthrough of the injected CO2 was established, which resulted in the production of about 10% of the injected CO2 in this period. This paper reports on activities performed under the European Commission project MOVECBM that aimed at the assessment of the storage performance of the reservoir in the follow-up period, i.e. whether the injected CO2 was adsorbed onto the coal or whether it was still present as free gas in the pore space. The injection well was used for this purpose, as the production well had to be abandoned for permitting reasons. Several operational periods can be defined between the last injection in June 2005 and the abandonment of the well in October 2007. In the first period the well was shut-in to observe the pressure fall-off, from about 15.0 MPa at the wellhead after the last injection until about 4.5 MPa at the end of 2005. This pressure fall-off curve showed that the reservoir permeability was very low. This seemed to confirm the observed swelling of the coal during the injection period. In the first months of 2006 the pressure at the wellhead was decreased by releasing gas in a controlled way. The amount and composition of the gas were measured. As a result of the pressure reduction, the well flooded with water. A production pump was placed on the former injection well, enabling active production from the coal from March to September 2007. Results of these operations showed that whereas the gas production rates were as expected based on the experience with the production well, the water production was remarkably low. This could be related to permeability issues or, alternatively, indicate a drying effect of the CO2 in the reservoir. Further, the gas composition showed a predominance of CO2 over CH4 during the gas release that changed gradually into a predominance of CH4 over CO2 during the production phase. Although stabilization was not reached within the given production period, the composition approached a 60% methane, 40% CO2 ratio. This indicates that the exchange of these gases is more complex than often envisaged. After removal of the pump the well was filled with water, which ceased the gas release. This indicates that the pressure in the reservoir was back to its original, hydrostatic, state. As the total volume of CO2 produced was only a fraction of the amount that was injected, it can be concluded that the CO2 was taken up by the coal and is currently adsorbed. This gives confidence in the long-term stability of the injected CO2. © 2008 Elsevier B.V. All rights reserved.

A case of a patient with congenital anomaly of coronary blood vessels with left anterior descending artery starting from right coronary sinus is presented. The patient was operated on due to symptoms of myocardial ischaemia by carrying out an off-pump coronary artery bypass graft to left anterior descending artery and obtuse marginal artery, with a very good outcome.

A018 Monitoring techniques applied for CO2 injection in coal Abstract 1 To demonstrate that CO2 injection in coal under European conditions is feasible and that CO2 storage is a safe and permanent solution and that coal bed methane can be produced in the same process the EC funded RECOPOL project is being carried out. In order to improve the understanding of storage in coal to verify that safety and environment are not jeopardised and to determine that the CO2 is injected into the intended coal layers an extensive monitoring programme is applied. This monitoring programme is based on FEP analyses

A pilot site for CO2 storage in coal seams was set-up in Poland, as has been reported on previous GHGT conferences. This site consisted of one injection and one production well. About 760 ton of CO2 has been injected into the reservoir from August 2004 to June 2005. Breakthrough of the injected CO2 was established, which resulted in the production of about 10% of the injected CO2 by the production well in this period. A follow-up EC project, MOVECBM, aimed at determining the storage performance of the reservoir, i.e. whether the injected CO2 was adsorbed onto the coal or whether it was still present as free gas in the pore space. The injection well was used for this purpose, because the production well had to be abandoned for permitting reasons. Several operational periods can be defined between the last injection in June 2005 and the abandonment of the well in October 2007. In the first period the well was shut-in to observe the pressure fall-off, followed by a decrease of pressure at the wellhead by releasing gas in a controlled way in the first months of 2006. The amount and composition of the gas were measured. As a result of the pressure reduction, the well flooded with water. A production pump was placed on the former injection well, enabling active production from the coal from March to September 2007. Results of these operations showed that whereas the gas production rates were as expected based on the experience with the production well, the water production was remarkably low. Further, the gas composition showed a predominance of CO2 over CH4 during the gas release that changed gradually into a predominance of CH4 over CO2 during the production phase. Although stabilization was not reached within the production period, the composition approached a 60% methane, 40% CO2 ratio. This indicates that the exchange of these gases is more complex than often envisaged. After removal of the pump the well was filled with water, which ceased the gas release. This indicates that the pressure in the reservoir was back to its original, hydrostatic, state. As the total volume of CO2 produced was only a fraction of the amount that was injected, it can be concluded that the CO2 was taken up by the coal and is currently adsorbed. This gives confidence in the long-term stability of the injected CO2. In conclusion, the field demonstration in Poland has been a successful experiment. Lessons learned in this demonstration indicate that the volumes that can be injected in low permeability coal seams (