Relationship between vertical jump tests and ice skating performance in junior Polish ice hockey players.

The aim of this study was to determine the relationships between vertical jumps (VJ) and various on-ice skating performances of junior ice hockey players (n = 19). The three modes of VJ or off-ice measures were countermovement jump with arm swing (CMJ), squat jump (SJ) and depth drop jump (DDJ). The on-ice skating performance was measured by the skating multistage aerobic test (SMAT), forward and backward acceleration test, top speed test, and repeated sprint ability (RSA) test. The relationships between the variables were quantified using Pearson's product-moment correlation. DDJ showed a significant positive correlation with forward average skating speed (FASS) (r = 0.62) and strong correlations with backward average skating speed (BASS) (r = 0.81), and maximum skating speed (MSS) (r = 0.71). SJ was found to be strongly correlated with BASS (r = 0.82) and MSS (r = 0.76), whereas the only on-ice performance that significantly correlated with CMJ was BASS (r = 0.68). All three modes of VJ were inversely and non-significantly correlated with performance decrement index and fatigue index, as determined by the RSA test. SMAT was not significantly correlated with either VJ or RSA. Correlations between all three modes of VJ tests were significant. Therefore, this study concludes that: (1) DDJ can be used as a predictor of all the ice skating speed tests, whereas SJ can predict BASS and MSS. CMJ, on the other hand, can predict the performance of only BASS. (2) RSA performance cannot be predicted from CMJ, SJ, or DDJ tests, and (3) neither any of the VJ nor RSA can predict skating endurance of junior ice hockey players.

Value, time and outcomes of elevated lactate levels in adult patients on extracorporeal membrane oxygenation.

INTRODUCTION: Lactate levels have been recognized as a reliable tool for monitoring critically ill patients requiring venoarterial extracorporeal membrane oxygenation (VA ECMO) or venovenous extracorporeal membrane oxygenation (VV ECMO) but the reasons behind the overproduction of lactate are different and the influance for survival remains controversial. We analyzed the lactate values and lactate clearance in adult patients in these two forms of extracorporeal support. METHODS: Patient demographics, ECMO duration, 30-day mortality, lactate values and lactate clearance at 24, 48 and 72 h from ECMO initiation of patients supported with VV and VA ECMO at Silesian Centre for Heart Deasese, between January 2011 and April 2020 were retrospectively analyzed. The changes in lactate levels were analyzed using the non-parametric U Mann-Whitney tests and Chi-square test. The ROC curves were draw and the area under the curve was calculated. RESULTS: The study comprised 91 adult patients, Mortality in the first 30 days from initiation of VV and VA ECMO was 39% and 66%, respectively. Lactate levels were significantly higher in non-survivors that received VV and VA ECMO (p < .001), while lactate clearance was similar (p = .256 and p = 1.000, respectively). Survival curves for patients with elevated (>2.0 mmol/L) vs normal (≤2.0 mmol/L) lactate levels at 72 h were significantly different for VV ECMO (p = .007) and VA ECMO (p = .037) but in both groups of ECMO, lactate levels above 2.0 mmol/L at 72 h from ECMO initiation predicted 30 day-mortality. CONCLUSION: This results emphasized the importance of lactate levels below 2.0 mmol/L at 72 h from both VV and VA ECMO initiation.

Total Occlusion of the Infarct-Related Artery in Non-ST-Elevation Myocardial Infarction (NSTEMI)-How Can We Identify These Patients?

Background and Objectives: Regardless of the improvement in key recommendations in non-ST-elevation myocardial infarction (NSTEMI), the prevalence of total occlusion (TO) of infarct-related artery (IRA), and the impact of TO of IRA on outcomes in patients with NSTEMI, remain unclear. Aim: The study aimed to assess the incidence and predictors of TO of IRA in patients with NSTEMI, and its clinical significance. Material and Methods: The study was a single-center retrospective cohort analysis of 399 consecutive patients with NSTEMI (293 male, mean age: 71 ± 10.1 years) undergoing percutaneous coronary intervention. The study population was categorized into patients with TO and non-TO of IRA on coronary angiography. In-hospital and one-year mortality were analyzed. Results: TO of IRA in the NSTEMI population occurred in 138 (34.6%) patients. Multivariate analysis identified the following independent predictors of TO of IRA: left ventricular ejection fraction (odds ratio (OR) 0.949, p < 0.001); family history of coronary artery disease (CAD) (OR 2.652, p < 0.001); and high-density lipoprotein (HDL) level (OR 0.972, p = 0.002). In-hospital and one-year mortality were significantly higher in the TO group than the non-TO group (2.8% vs. 1.1%, p = 0.007 and 18.1% vs. 6.5%, p < 0.001, respectively). The independent predictors of in-hospital mortality were: left ventricular ejection fraction (LVEF) at admission (OR 0.768, p = 0.004); and TO of IRA (OR 1.863, p = 0.005). Conclusions: In the population of patients with NSTEMI, TO of IRA represents a considerably frequent phenomenon, and corresponds with impaired outcomes. Therefore, the utmost caution should be paid to prevent delay of coronary angiography in NSTEMI patients with impaired left ventricular systolic function, metabolic disturbances, and a family history of CAD, who are at increased risk of TO of IRA.

The influence of chlorine in indoor swimming pools on the composition of breathing phase of professional swimmers.

OBJECTIVES: Swimming is one of the most popular forms of physical activity. Pool water is cleaned with chlorine, which - in combination with compounds contained in water - could form chloramines and trichloromethane in the swimmer's lungs. The aim of the present study was to examine the effect of swimming training in an indoor pool on the composition of swimmers' respiratory phase metabolomics, and develop a system to provide basic information about its impact on the swimmer's airway mucosa metabolism, which could help to assess the risk of secondary respiratory tract diseases i.e. sport results, condition, and health including lung acute and chronic diseases). DESIGN: A group of competitive swimmers participated in the study and samples of their respiratory phase before training, immediately after training, and 2 h after training were assessed. METHODS: Sixteen male national and international-level competitive swimmers participated in this study. Respiratory phase analysis of the indoor swimming pool swimmers was performed. Gas chromatography combined with mass spectrometry (GCMS) was used in the measurements. All collected data were transferred to numerical analysis for trends of tracking and mapping. The breathing phase was collected on special porous material and analyzed using GCMS headspace. RESULTS: The obtained samples of exhaled air were composed of significantly different metabolomics when compared before, during and after exercise training. This suggests that exposition to indoor chlorine causes changes in the airway mucosa. CONCLUSION: This phenomenon may be explained by occurrence of a chlorine-initiated bio-reaction in the swimmers' lungs. The obtained results indicate that chromatographic exhaled gas analysis is a sensitive method of pulmonary metabolomic changes assessment. Presented analysis of swimmers exhaled air indicates, that indoor swimming may be responsible for airway irritation caused by volatile chlorine compounds and their influence on lung metabolism.

Analysis of molecular and clinical parameters of 4-year adalimumab therapy in psoriatic patients.

INTRODCUTION: Through interaction with receptors TNFR1 and TNFR2, TNF-α activates a signal path, which exacerbates an inflammatory process, constituting an inseparable element of psoriasis. AIM: To evaluate changes in the expression of TNF-α, TNFR1, TNFR2 during the 4-year-long adalimumab therapy in psoriatic patients, searching for the correlation between molecular and clinical markers. In addition, the role of miRNAs was analysed. MATERIAL AND METHODS: Whole blood and serum samples of psoriatic patients treated with adalimumab constituted material for the study. Changes in the expression of TNF-α and its receptors were evaluated with the use of the RTqPCR method and MALDI ToF mass spectroscopy, PASI, BSA, DAS28 indexes were used for the clinical analysis of the patients, while the role of miRNA molecules was determined basing on microrna.org database. RESULTS: Different TNF-α expression patterns were determined in patients with observed resistance to the medicine. We found that there is a correlation between the molecular markers of an inflammatory process and the clinical indexes. The bioinformatic analysis indicates the potential role of miRNAs in the regulation of expression of the analysed genes. Changes in the profile of TNF-α during adalimumab therapy are significantly determined by the individual variability and susceptibility to the biological medicine or its loss. CONCLUSIONS: TNF-α seems to be a useful marker to evaluate the efficacy of therapy and occurring resistance to the medicine. A complex mechanism for the regulation of the analysed gene expression was underlined, which involved the potential role of miRNAs.

Comprehensive molecular and clinical analysis of adalimumab and etanercept therapeutic potential in patients with psoriatic arthritis.

INTRODUCTION: Adalimumab and etanercept are drugs used in anti-TNF therapy in patients with psoriasis and psoriatic arthritis. Despite the molecular targeting of these drugs, the loss of pharmacological response to treatment is observed in patients. The development of personalized medicine makes it possible to use not only clinical parameters of disease severity, but also molecular marker systems. AIM: The aim of the study was to evaluate the changes in TNF-α, TNFR1, and TNFR2 expression in relation to parameters of disease severity (PASI, BSA, DAS28) in patients treated with adalimumab and etanercept. We have attempted to determine whether changes in the TNF-α, TNFR1, and TNFR2 expression profile may be a useful molecular marker of the therapeutic potential of anti-TNF drugs. MATERIAL AND METHODS: The study group consisted of 3 patients initially treated with adalimumab, followed by etanercept. The control group included 20 healthy volunteers. The expression profile of TNFR1 and TNFR2 was determined at the mRNA level, while TNF-α expression was evaluated at the transcriptome and proteome levels using the RT-qPCR method (transcriptional activity assay) and MALDI-TOF MS (protein level assessment). RESULTS: Depending on the drug, different expression profiles of the studied cytokines are observed. CONCLUSIONS: The obtained data indicate that TNF-α, TNFR1, and TNFR2 may be useful markers of the efficacy of anti-TNF therapy, thus complementing clinical parameters.

The Measurement of the Oxidative Index of Polyethylene Obtained during Revision Hip Arthroplasty and Assessment of Its Variability Depending on the Degree of Osteolysis, Implantation Time, as Well as the Size and Material of the Utilized Head.

Background/Objectives: Aseptic loosening is the leading cause of late revision in total hip arthroplasty, primarily due to degenerative oxidation of polyethylene components, leading to wear particle formation and periacetabular osteolysis. This study aimed to analyze the oxidation levels in polyethylene liners and cemented cups retrieved from revision surgeries using Fourier-transform infrared spectroscopy (FTIR) and to explore the correlation between oxidation levels and factors such as head size, head material, fixation method, and implant survival time. Methods: Polyethylene liners and cups were analyzed post-revision surgery to assess oxidation levels, which were then compared to periacetabular bone loss measured by the Paprosky classification. This study evaluated the impact of head size (28 mm vs. 32 mm), head material (ceramic vs. metal), and fixation methods on oxidation. The relationship between the mean oxidation index (OI) and implant survival time was also investigated. Results: There was a significant positive correlation between the mean oxidation index of the polyethylene components and the severity of periacetabular osteolysis according to the Paprosky scale. While the mean OI for samples articulating with ceramic heads was lower than for those with metal heads, and the mean OI for samples with a 32 mm head size was lower than for those with a 28 mm size, these differences were not statistically significant. Furthermore, the fixation method did not affect the oxidation index, and no correlation was found between OI and the survival time of the implants. Conclusions: This study confirms a direct correlation between polyethylene oxidation and periacetabular osteolysis in hip replacements, highlighting the importance of material choice and design in potentially reducing the risk of aseptic loosening. Despite the lack of significant differences in oxidation levels based on head material and size, these factors may still play a role in the long-term outcome of hip arthroplasty, warranting further investigation.

Enhancing Patient Selection in Stage IIIA-IIIB NSCLC: Invasive Lymph Node Restaging after Neoadjuvant Therapy.

Restaging of mediastinal lymph nodes plays a crucial role in the multimodal treatment of stage IIIA Non-Small-Cell Lung Cancer (NSCLC). This study aimed to assess the impact of restaging using endobronchial ultrasound (EBUS), endoesophageal ultrasound (EUS), and transcervical extended mediastinal lymphadenectomy (TEMLA) after neoadjuvant chemotherapy (CHT) or chemoradiotherapy (CRT) on the 5-year overall survival (OS) of patients with NSCLC diagnosed with clinical stage IIIA-IIIB and metastatic ipsilateral mediastinal nodes (N2) who underwent radical pulmonary resections. Patients diagnosed with stage IIIA-IIIB NSCLC and N2 mediastinal nodes were included in this study. Restaging of mediastinal lymph nodes was performed using EBUS, EUS, and TEMLA. The patients were divided into two groups based on the restaging method: the TEMLA restaging group and the chest CT scan-only group. The primary outcome measure was the 5-year OS rate, and the secondary outcome measures included median OS and survival percentages. Statistical analysis, including the log-rank test, was conducted to assess the differences between the two groups. The TEMLA restaging group demonstrated significantly better overall survival compared to the chest CT scan-only group (log-rank test, p = 0.02). This was evident through a four-fold increase in median OS (59 vs. 14 months) and a higher 5-year OS rate of 55.9% (95% CI: 40.6-71.1) compared to 25.0% (95% CI: 13.7-36.3) in the chest CT scan-only group (p = 0.003). Invasive restaging of mediastinal lymph nodes improves the selection of patients with stage IIIA-IIIB (N2) NSCLC after neoadjuvant therapy. The use of EBUS, EUS, and TEMLA provides valuable information for identifying patients who may benefit from surgery by identifying N2 to N0-1 downstaging. These findings emphasize the importance of incorporating restaging procedures into the treatment decision-making process for NSCLC patients with mediastinal lymph node involvement.

Influence of Aortic Valve Stenosis and Wall Shear Stress on Platelets Function.

Aortic valve stenosis (AS) is a common heart valve disease in the elderly population, and its pathogenesis remains an interesting area of research. The degeneration of the aortic valve leaflets gradually progresses to valve sclerosis. The advanced phase is marked by the presence of extracellular fibrosis and calcification. Turbulent, accelerated blood flow generated by the stenotic valve causes excessive damage to the aortic wall. Elevated shear stress due to AS leads to the degradation of high-molecular weight multimers of von Willebrand factor, which may involve bleeding in the mucosal tissues. Conversely, elevated shear stress has been associated with the release of thrombin and the activation of platelets, even in individuals with acquired von Willebrand syndrome. Moreover, turbulent blood flow in the aorta may activate the endothelium and promote platelet adhesion and activation on the aortic valve surface. Platelets release a wide range of mediators, including lysophosphatidic acid, which have pro-osteogenic effects in AS. All of these interactions result in blood coagulation, fibrinolysis, and the hemostatic process. This review summarizes the current knowledge on high shear stress-induced hemostatic disorders, the influence of AS on platelets and antiplatelet therapy.

Influence of Surface Structure on Ball Properties during a Professional Water Polo Game.

The use of modern materials in sports, in terms of chemical composition and surface texture, entails both progress in results and an increasing discrepancy in the technical parameters of the equipment used. This paper aims to demonstrate the differences between balls admitted to a league and world championships in composition, surface texture, and the influence of these parameters on the water polo game. This research compared two new balls produced by top companies producing sports accessories (Kap 7 and Mikasa). To obtain the goal, the measurement of the contact angle, analysis of the material using Fourier-transform infrared spectroscopy, and optical microscopic evaluation were used. The analysis of the surface free energy shows significant differences (Kap 7 32.16 mJ/m2, Mikasa 36.48 mJ/m2). In the case of both balls, anisotropies of the structure of the furrows were observed, however, the Mikasa ball is slightly more homogeneous than the Kap 7 ball. The obtained results from the analysis of the contact angle, as well as the composition and real feedback from the players, indicated the need to standardize the material aspect of the regulations so that the sports results are repeatable every time.

Autopsy Histopathologic Lung Findings in Patients Treated With Extracorporeal Membrane Oxygenation.

CONTEXT.­: Extracorporeal membrane oxygenation (ECMO) is increasingly used in the treatment of respiratory and cardiac failure, but data describing lung histopathology in ECMO recipients are limited. OBJECTIVE.­: To examine pulmonary histopathologic findings in patients who underwent venovenous (VV) ECMO for pulmonary reasons, or venoarterial (VA) ECMO for cardiac indications shortly before death, and to determine if the pulmonary changes provided insights into therapy that may prevent complications and improve outcome. DESIGN.­: We conducted a retrospective study of lung autopsies, from VV and VA ECMO recipients and patients with acute respiratory distress syndrome (ARDS) and non-ECMO treatment, between 2008 and 2020 in Silesia Center for Heart Diseases in Zabrze, Poland. RESULTS.­: Among 83 ECMO patients (42-64 years; male, 57 [68.7%]), the most common histopathologic findings were bronchopneumonia (44 [53.0%]), interstitial edema (40 [48.2%]), diffuse alveolar damage (DAD; 32 [38.6%]), hemorrhagic infarct (28 [33.7%]), and pulmonary hemorrhage (25 [30.1%]). DAD was associated with longer ECMO treatment and longer hospital stay. The use of VV ECMO was a predictor of DAD in patients with ARDS and undergoing ECMO, but it also occurred in 21 of 65 patients (32.3%) in the VA ECMO group, even though VA ECMO was used for heart failure. CONCLUSIONS.­: Although DAD was significantly more common in lung autopsies of VV ECMO patients, one-third of VA ECMO patients had histopathologic changes characteristic of ARDS. The presence of DAD in lung autopsies of patients treated with VA ECMO indicates that in these patients, protective lung ventilation should be considered.

The use of non-invasive respiratory assistance to facilitate bronchofiberoscopy performance in patients with hypoxemic (type one) respiratory failure - Study protocol.

PURPOSE: Bronchofiberoscopy (FOB) is a procedure routinely performed for: lung cancer, obstruction, interstitial diseases, foreign bodies' removal, airway clearance, and hemoptysis. It causes acute airway narrowing leading to respiratory and cardiovascular stress. Due to increasing number of ill patients with respiratory failure (RF), conventional oxygen therapy (COT) is frequently insufficient to assure accurate oxygenation and prevent RF in patients requiring FOB. In this clinical scenario, patients may be intubated and supported with invasive mechanical ventilation (IMV) with the specific aim of allowing a safe FOB. However, this invasive strategy is associated with an increased risk of IMV-associated complications. MATERIALS AND METHODS: Our study is a planned prospective multicenter three-arm randomized controlled trial (RCT). The target number of 300 patients was calculated based on the intubation risk in RF patients, which is 0.2-2%. The patients will be assigned to each arm based on Horowitz index. In each arm, the patients will be randomly assigned to one out of two dedicated respiratory support methods in each group i.e. COT/high flow nasal cannula (HFNC), HFNC/non-invasive ventilation (NIV) and NIV/IMV. In the manuscript the current state of art in the area of respiratory support is discussed. We have underlined knowledge gaps in medical evidence which we are planning to reveal with our results. RESULTS: The results of our study are clinically crucial, because they address current gaps concerning COT/HFNC/NIV/IMV. CONCLUSION: The expected findings of this study would allow for careful selection of respiratory support method to safely perform FOB in patients with hypoxemic RF.

May noninvasive mechanical ventilation and/ or continuous positive airway pressure increase the bronchoalveolar lavage salvage in patients with pulmonary diseases? Randomized clinical trial - Study protocol.

PURPOSE: Bronchoalveolar lavage (BAL) procedure is a useful tool in the diagnosis of patients with interstitial lung disease (ILD) and is helpful in clinical research of chronic obstructive pulmonary disease (COPD) patients. Still little is known about predictors of poor BAL salvage. The trial aims to find the most efficient way to improve BAL recovery. MATERIAL AND METHODS: Our study is a prospective, multicenter, international, two-arm randomized controlled trial. We aim to obtain BAL samples from a total number of 300 patients: 150 with ILD and 150 with COPD to achieve a statistical power of 80 â€‹%. Patients with initial BAL salvage <60 â€‹% will be randomized into the non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP) arm. The NIV and CPAP will be set according to the study protocol. The influence on BAL salvage will be assessed in terms of BAL volume and content. Multivariable analysis of the additional test results to determine predictors for low BAL recovery will be conducted. In a study subgroup of approximately 20 patients per specific disease, a metabolomic assessment of exhaled air condensate will be performed. All procedures will be assessed in terms of the patient's safety. The trial was registered on clinicaltrials.gov (ID# NCT05631132). Interested experienced centers are invited to join the research group by writing to the corresponding author. CONCLUSION: The results of our prospective study will address the currently unsolved problem of how to increase BAL salvage in patients with pulmonary diseases without increasing the risk of respiratory failure exacerbation.

Surgery Training System Supported by Organic Materials.

The aim of the study was the qualitative assessment of new materials based on a polycarbonate matrix in terms of its use in 3D printing and its processing and geometric modification (cutting). Filaments made of the new material doped with talc in five different proportions were visually inspected with a microscope. The calibration and test models were made using the FFF (fused filament fabrication) technique. In addition, its susceptibility to the drill and the behavior of the shavings were assessed and the temperature changing during drilling was measured. The implant was inserted to measure its resonance stability in each of the holes made and translated into the value of the implant stability quotient (ISQ) ranging from 1 to 100. The results were compared to those obtained for the training model of the skull bone. The amount of filler has been shown to affect the composite. Moreover, due to the properties of talc, a compatibilizer (polyol) was used. Differences were observed between the model made of the commercial material, the model made of the dried, tested material, and the model made of the undried material. It was confirmed that the presence of water in the material during its processing is important.

Cenospheres-Reinforced PA-12 Composite: Preparation, Physicochemical Properties, and Soaking Tests.

The main aim of this research was the preparation of a polymer-ceramic composite with PA-12 as the polymer matrix and modified aluminosilicate cenospheres (CSs) as the ceramic filler. The CSs were subjected to an early purification and cleaning process, which was also taken as a second objective. The CSs were surface modified by a two-step process: (1) etching in Piranha solution and (2) silanization in 3-aminopropyltriethoxysilane. The composite was made for 3D printing by FDM. Raw and modified CSs and a composite with PA-12 were subjected to the following tests: surface development including pores (BET), real density (HP), chemical composition and morphology (SEM/EDS, FTIR), grain analysis (PSD), phase composition (XRD), hardness (HV), and static tensile tests. The composites were subjected to soaking under simulated body fluid (SBF) conditions in artificial saliva for 14, 21, and 29 days. Compared to pure PA-12, PA-12_CS had generally better mechanical properties and was more resistant to SBF at elevated temperatures and soaking times. These results showed this material has potential for use in biomedical applications. These results also showed the necessity of developing a kinetic aging model for aging in different liquids to verify the true value of this material.

ARNI in HFrEF-One-Centre Experience in the Era before the 2021 ESC HF Recommendations.

BACKGROUND: Sacubitril/valsartan, an angiotensin receptor-neprilysin inhibitor (ARNI), has demonstrated a survival benefit and reduces heart failure hospitalization in patients with heart failure with reduced left ventricular ejection fraction (HFrEF); however, our experience in this field is limited. This study aimed to summarize a real clinical practice of the use of ARNI in HFrEF patients hospitalized due to HFrEF in the era before the 2021 ESC HF recommendations, as well as assess their clinical outcome with regard to ARNI administration. METHODS AND MATERIALS: Overall, 613 patients with HFrEF hospitalized in 2018-2020 were enrolled into a retrospective one-centre cross-sectional analysis. The study population was categorized into patients receiving (82/13.4%) and not-receiving (531/82.6%) ARNI. Clinical outcomes defined as rehospitalization, number of rehospitalizations, time to the first rehospitalization and death from any cause were analysed in the 1-2 year follow-up in the ARNI and non-ARNI groups, matched as to age and LVEF. RESULTS: Clinical characteristics revealed the following differences between ARNI and non-ARNI groups: A higher percentage of cardiovascular implantable electronic devices (CIED) (p = 0.014) and defibrillators with cardiac resynchronization therapy (CRT-D) (p = 0.038), higher frequency of atrial fibrillation (p = 0.002) and history of stroke (p = 0.024) were in the ARNI group. The percentage of patients with HFrEF NYHA III/IV presented an increasing trend to be higher in the ARNI (64.1%) as compared to the non-ARNI group (51.5%, p = 0.154). Incidence of rehospitalization, number of rehospitalizations and time to the first rehospitalization were comparable between the groups. There were no differences between the numbers of deaths of any cause in the ARNI (28%) and non-ARNI (28%) groups. The independent negative predictor of death in the whole population of ARNI and non-ARNI groups was the coexistence of coronary artery disease (CAD) (beta= -0.924, HR 0.806, p = 0.011). CONCLUSIONS: Our current positive experience in ARNI therapy is limited to extremely severe patients with HFrEF. Regardless of the more advanced HF and HF comorbidities, the patients treated with ARNI presented similar mortality and rehospitalizations as the patients treated by standard therapy.

The Effects of Two Different Rest Intervals on the Repeated Skating Ability of Ice Hockey Forwards and Defensemen.

The purpose of this study was to evaluate the effects of two different rest intervals (2 min and 3 min), between two consecutive sets of repeated sprint skating ability (RSSA) tests, on the repeated sprint ability of ice hockey Forwards and Defensemen. Two protocols of RSSA tests, RSSA-2 and RSSA-3, were completed by 16 ice hockey Forwards and 8 Defensemen. Defensemen were heavier (p < 0.05) than Forwards, although their % body fat did not differ significantly. In RSSA-2, athletes performed six sets of 3×80 m sprint skating with 2 min passive recovery between two consecutive sets. In RSSA-3, the rest interval between the sets was 3 min. Average speed, average heart rate (HRaver), blood lactate concentration ([BLa]), and the rate of perceived exertion (RPE) were measured in both RSSA-2 and RSSA-3 tests. Both Forwards and Defensemen skated faster in RSSA-3 than in the corresponding set of RSSA-2. Forwards were faster than Defensemen in both the tests, however, the difference was significant (p < 0.05) only in RSSA-2. In Forwards and Defensemen, HRaver increased gradually from set 1 through set 6 in RSSA-2 and RSSA-3. In most of the sets, RPE was higher in RSSA-2 than in RSSA-3, and Defensemen perceived higher exertion than Forwards. No difference in [BLa] was noted between Forwards and Defensemen, although players of both positions showed higher [BLa] in RSSA-3 than in RSSA-2. This study concludes that (1) Forwards skate faster than Defensemen, (2) average heart rate and [BLa] do not vary between Forwards and Defensemen, and (3) a higher perceived exertion is observed in Defensemen than Forwards during repeated sprint skating tests.

Production of Electrolytic Composite Powder by Nickel Plating of Shredded Polyurethane Foam.

Ni-poly(DPU) composite powder was produced under galvanostatic conditions from a nickel bath with the addition of pulverized polymer obtained during the shredding of polyurethane foam (poly(DPU)). The Ni-poly(DPU) composite powder was characterized by the presence of polymer particles covered with an electrolytical amorphous-nanocrystalline nickel coating. The phase structure, chemical composition, morphology, and the distribution of elements was investigated. The chemical analysis showed that the powder contains 41.7% Ni, 16.4% C, 15.7% O, 8.2% P and 0.10% S. The other components were not determined (nitrogen and hydrogen). The phase analysis showed the presence of NiC phase. Composite powder particles are created as a result of the adsorption of Me ions on the fragmented polymer. The current flowing through the galvanic bath forces the flow of the particles. The foam particles with adsorbed nickel ions are transported to the cathode surface, where the Ni2+ is discharged. The presence of compound phosphorus in galvanic solution generates the formation of amorphous-nanocrystalline nickel, which covers the polymer particles. The formed nickel-polymer composite powder falls to the bottom of the cell.

Polyurethane-Based Porous Carbons Suitable for Medical Application.

The main aim of the study was to synthesize and analyze spectral data to determine the structure and stereometry of the carbon-based porous material internal structure. Samples of a porous biomaterial were synthesized through anionic polymerization following our own patent and then carbonized. The samples were investigated using MALDI ToF MS, FTIR ATR spectroscopy, optic microscopy, SEM, confocal laser scanning microscopy and CMT imaging. The analysis revealed the chemical and stereological structure of the obtained porous biomaterial. Then, the parameters characterizing the pore geometry and the porosity of the samples were calculated. The developed material can be used to collect adsorption of breathing phase samples to determine the parity composition of exhaled air.

Individual Determinants as the Causes of Failure in Learning to Swim with the Example of 10-Year-Old Children.

BACKGROUND: The purpose of the present study was to identify which, and to what extent, selected individual determinants of 10-year-old children may limit the final achievement in learning to swim. In view of the above, the research hypothesis was formulated that some children, despite regular attendance at swimming classes, do not achieve the learning outcomes set in the curriculum. The reason for this may be unfavorable (compared to their peers) morphological and functional characteristics, coordination motor abilities, and problems with fear of water. METHODS: The study was conducted on a group of 271 students from the third grade of elementary schools who could not swim when they entered the physical education classes at the swimming pool and then participated in at least 25 swimming lessons during the school year. After these classes, the students performed swimming tests, and their somatic and functional characteristics and coordination motor abilities were measured. RESULTS: In 46.1% of the participants, the final achievement level was lower than assumed in the school curriculum. The biggest problem for teachers and students in the initial teaching and learning to swim was the high fear of water, especially among girls. Furthermore, children characterized by lower body height and body weight, a lower sum of three skinfolds, and lower BMI had problems with progress in swimming. Despite the differences, these values did not correlate significantly with the final achievement level in swimming, except for body height in boys. Slower progress in swimming was also associated with lower vital capacity, whereas no relationship was found between final achievement level in swimming and trunk flexibility or foot mobility. However, significant correlations occurred for coordination motor abilities, as in almost all tests the participants characterized by the achievement level below the objectives set out in the curriculum performed significantly worse than children in the group with the achievement level meeting the objectives. CONCLUSIONS: In many cases, children who begin learning to swim from scratch make significant progress, but for many of them, the achievement levels are lower than the requirements set out in the school curriculum. The biggest problem for teachers and students in the initial teaching and learning to swim was the high fear of water, especially among girls.