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1.
Arch Pathol Lab Med ; 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37931217

ABSTRACT

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.

2.
Materials (Basel) ; 16(8)2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37109884

ABSTRACT

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.

3.
Perfusion ; : 2676591221130177, 2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36168831

ABSTRACT

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.

4.
Materials (Basel) ; 15(11)2022 May 30.
Article in English | MEDLINE | ID: mdl-35683192

ABSTRACT

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.

5.
Materials (Basel) ; 15(12)2022 Jun 12.
Article in English | MEDLINE | ID: mdl-35744221

ABSTRACT

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.

6.
Polymers (Basel) ; 14(12)2022 Jun 09.
Article in English | MEDLINE | ID: mdl-35745908

ABSTRACT

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.

7.
Materials (Basel) ; 15(9)2022 May 05.
Article in English | MEDLINE | ID: mdl-35591653

ABSTRACT

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.

8.
Article in English | MEDLINE | ID: mdl-35206278

ABSTRACT

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.


Subject(s)
Aminobutyrates , Angiotensin Receptor Antagonists , Biphenyl Compounds , Heart Failure , Valsartan , Ventricular Dysfunction, Left , Aminobutyrates/therapeutic use , Angiotensin Receptor Antagonists/therapeutic use , Biphenyl Compounds/therapeutic use , Cross-Sectional Studies , Drug Combinations , Heart Failure/drug therapy , Heart Failure/epidemiology , Humans , Retrospective Studies , Stroke Volume , Treatment Outcome , Valsartan/therapeutic use , Ventricular Dysfunction, Left/drug therapy , Ventricular Dysfunction, Left/epidemiology , Ventricular Function, Left
9.
J Biomed Mater Res B Appl Biomater ; 110(2): 367-381, 2022 02.
Article in English | MEDLINE | ID: mdl-34302425

ABSTRACT

Implantation of ureteral stents is associated with inconvenience for the patient, which is related to the natural ability of the ureter to contract. The most frequently used solution is the systemic administration of a diastolic drug, which has a relaxing effect on smooth muscle cells and decreases inconvenience. Current interdisciplinary research aimed at reducing the complications after the implantation of ureteral stents used in the treatment of upper urinary tracts with regard to infection, initiation of encrustation, and fragmentation of stents, and patient pain has not been resolved. This study presents the results of research regarding the impact of a biodegradable coating with the active substance on the physical and chemical properties of ureteral stents used in the treatment of the upper urinary tract. The surface of polyurethane double-J stents was coated with poly(lactide-glycolide) (PLGA) 85/15 loaded with papaverine hydrochloride (PAP) with diastolic properties. The coating for ureteral stents has been designed for short-term implantation. The effect of the coating on the process of encrustation and PAP release by the dynamic in vitro model with artificial urine (AU) up to 30 days was evaluated. The influence of AU on the physical and chemical properties of ureteral stents was determined. As part of the study, surface structure and topography researches; chemical composition analyses using X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and wetting; and surface roughness studies of both PUR stents and coated stents were carried out. The proposed biodegradable PLGA+PAP coating is characterized by controlled drug release, while optimal physicochemical properties does not increase the encrustation process.


Subject(s)
Papaverine , Ureter , Dioxanes , Humans , Papaverine/pharmacology , Polyurethanes/chemistry , Polyurethanes/pharmacology , Stents
10.
Article in English | MEDLINE | ID: mdl-36612835

ABSTRACT

Pulmonary arterial hypertension (PAH) is a rare disease with a serious prognosis. The aim of this study was to identify biomarkers for PAH in the breath phase and to prepare an automatic classification method to determine the changing metabolome trends and molecular mapping. A group of 37 patients (F/M: 8/29 women, mean age 60.4 ± 10.9 years, BMI 27.6 ± 6.0 kg/m2) with diagnosed PAH were enrolled in the study. The breath phase of all the patients was collected on a highly porous septic material using a special patented holder PL230578, OHIM 002890789-0001. The collected air was then examined with gas chromatography coupled with mass spectrometry (GC/MS). The algorithms of Spectral Clustering, KMeans, DBSCAN, and hierarchical clustering methods were used to perform the cluster analysis. The identification of the changes in the ratio of the whole spectra of biomarkers allowed us to obtain a multidimensional pathway for PAH characteristics and showed the metabolome differences in the four subgroups divided by the cluster analysis. The use of GC/MS, supported with novel porous polymeric materials, for the breath phase analysis seems to be a useful tool in selecting bio-fingerprints in patients with PAH. The four metabolome classes which were obtained constitute novel data in the PAH population.


Subject(s)
Hypertension, Pulmonary , Pulmonary Arterial Hypertension , Humans , Female , Middle Aged , Aged , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/metabolism , Metabolome , Gas Chromatography-Mass Spectrometry/methods , Biomarkers/metabolism
11.
Materials (Basel) ; 14(21)2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34772121

ABSTRACT

Ni-P-ZrO2 composite powder was obtained from a galvanic nickel bath with ZrO2 powder. Production was conducted under galvanostatic conditions. The Ni-P-ZrO2 composite powder was characterized by the presence of ZrO2 particles covered with electrolytical nanocrystalline Ni-P coating. The chemical composition (XRF method), phase structure (XRD method) and morphology (SEM) of Ni-P-ZrO2 and the distribution of elements in the powder were all investigated. Based on the analyses, it was found that the obtained powder contained about 50 weight % Zr and 40 weight % Ni. Phase structure analysis showed that the basic crystalline component of the tested powder is a mixed oxide of zirconium and yttrium Zr0.92Y0.08O1.96. In addition, the sample contains very large amounts of amorphous compounds (Ni-P). The mechanism to produce the composite powder particles is explained on the basis of Ni2+ ions adsorption process on the metal oxide particles. Current flow through the cell forces the movement of particles in the bath. Oxide grains with adsorbed nickel ions were transported to the cathode surface. Ni2+ ions were discharged. The oxide particles were covered with a Ni-P layer and the heavy composite grains of Ni-P-ZrO2 flowed down to the bottom of the cell.

12.
Polymers (Basel) ; 13(20)2021 Oct 16.
Article in English | MEDLINE | ID: mdl-34685330

ABSTRACT

This research aimed to examine the mechanical properties of polycarbonate-based composites filled with both organic and inorganic reinforcements before and after simulated environmental degradation. Series of polycarbonate-based samples were prepared in the form of thin tapes. Their rheological properties were examined. Then, the samples were exposed to artificial environmental conditions. Finally, their rheological properties were examined once more, and the results were compared with those obtained for untreated samples. This paper presents basic research on the application of inorganic fillers to polycarbonate in order to determine the influence of the filler on the behavior of the obtained material. The aim of the work was to determine the usefulness and purpose of using this type of filler in polycarbonates for applications in contact with ultraviolet radiation, especially medical applications.

13.
Materials (Basel) ; 14(16)2021 Aug 21.
Article in English | MEDLINE | ID: mdl-34443247

ABSTRACT

In the era of modern medicine, the number of invasive treatments increases. Artificial devices used in medicine are associated with an increased risk of secondary infections. Bacterial biofilm development observed on the implanted surface is challenging to treat, primarily due to low antibiotics penetration. In our study, the preparation of a new polycarbonate composite, filled with nanosilver, nanosilica and rhodamine B derivative, suitable for three-dimensional printing, is described. Polymer materials with antimicrobial properties are known. However, in most cases, protection is limited to the outer layers only. The newly developed materials are protected in their entire volume. Moreover, the antibacterial properties are retained after multiple high-temperature processing were performed, allowing them to be used in 3D printing. Bacterial population reduction was observed, which gives an assumption for those materials to be clinically tested in the production of various medical devices and for the reduction of morbidity and mortality caused by multidrug-resistant bacteria.

14.
Materials (Basel) ; 14(9)2021 Apr 25.
Article in English | MEDLINE | ID: mdl-33923089

ABSTRACT

The main aim of this study was to analyze microtomographic data to determine the geometric dimensions of a ceramic porous material's internal structure. Samples of a porous corundum biomaterial were the research material. The samples were prepared by chemical foaming and were measured using an X-ray scanner. In the next stage, 3D images of the samples were generated and analyzed using Thermo Scientific Avizo software. The analysis enabled the isolation of individual pores. Then, the parameters characterizing the pore geometry and the porosity of the samples were calculated. The last part of the research consisted of verifying the developed method by comparing the obtained results with the parameters obtained from the microscopic examinations of the biomaterial. The comparison of the results confirmed the correctness of the developed method. The developed methodology can be used to analyze biomaterial samples to assess the geometric dimensions of biomaterial pores.

15.
Polymers (Basel) ; 12(10)2020 Oct 07.
Article in English | MEDLINE | ID: mdl-33036466

ABSTRACT

This article presents the results of research related to the development of cellulose man-made fibers with luminescent properties. The fibers were obtained from regenerated cellulose with the use of the N-Methylmorpholine-N-Oxide (NMMO) method for lyocell (Tencel) fiber formation. The method is named after the cellulose solvent (NMMO) used to obtain the spinning solution. Fibers are formed by the dry-wet spinning method. Due to the characteristic of the lyocell process, the fibers were easily modified to achieve luminescent properties with star-shaped organic compound poly((9-carbazolyl)methylthiirane) (KMT). Fibers were examined on their mechanical parameters with the use of Zwick Z2.5/TN1S tensile testing machine, and the results show the influence of the KMT concentration in the fiber matrix on mechanical parameters of the fibers. The study also attempted to determine the concentration of the modifier in the fibers with the use of UV-VIS Spectrofluorometer JASCO. The luminescent properties of fibers were estimated as well, using Jobin-Yvon spectrofluorometer FLUOROMAX-4, and the results are very promising as the fibers emit blue light in the range of visible light spectrum even for small concentrations of KMT (about 0.1 wt.%).

16.
Polymers (Basel) ; 12(8)2020 Jul 28.
Article in English | MEDLINE | ID: mdl-32731329

ABSTRACT

This research investigated the effect of irradiation with an electron beam energy of 10 MeV in doses of 26-156 kGy on polytetrafluoroethylene (PTFE) with a 15% and 20% graphite additive. The research has shown that mechanical (compression strength, hardness, and Young's modulus) and sclerometric (coefficient of wear micromechanism and coefficient of resistance to wear) properties improve and tribological wear decreases as graphite content increases. Electron beam irradiation increases the degree of crystallinity of both materials to a similar extent. However significant differences in the improvement of all examined properties have been demonstrated for PTFE with higher (20%) graphite content subjected to the electron beam irradiation. This polymer is characterized by higher hardness and Young's modulus, reduced susceptibility to permanent deformation, higher elasticity, compression strength, and above all, a nearly 30% reduction in tribological wear compared to PTFE with a 15% graphite additive. The most advantageous properties can be obtained for both of the examined composites after absorbing a dose of 104 kGy. The obtained results hold promise for the improvement of the operational life of friction couples which do not require lubrication, used for example in air compressors and engines, and for the possibility of application of these modified polymers. In particular PTFE with 20% graphite content, in the nuclear and space industry.

17.
Postepy Dermatol Alergol ; 37(2): 262-268, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32489364

ABSTRACT

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.

18.
Respir Res ; 21(1): 88, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-32295600

ABSTRACT

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.


Subject(s)
Chlorine/metabolism , Respiratory Mechanics/drug effects , Respiratory Mucosa/drug effects , Respiratory Mucosa/metabolism , Swimming Pools , Swimming/physiology , Chlorine/adverse effects , Chlorine/analysis , Humans , Male , Respiratory Function Tests/methods , Respiratory Mechanics/physiology , Young Adult
19.
Polymers (Basel) ; 12(2)2020 Feb 03.
Article in English | MEDLINE | ID: mdl-32028589

ABSTRACT

This study analyzed the effects of irradiation of polytetrafluoroethylene (PTFE) containing 40% of bronze using an electron beam with energy of 10 MeV. Dosages from 26 to156 kGy (2.6-15.6 Mrad) were used. The impact of a high-energy electron beam on the thermal, spectrophotometric, mechanical, and tribological properties was determined, and the results were compared with those obtained for pure PTFE. Thermal properties studies showed that such irradiation caused changes in melting temperature Tm and crystallization temperature Tc, an increase in crystallization heat ∆Hc, and a large increase in crystallinity χc proportional to the absorbed dose for both polymers. The addition of bronze decreased the degree of crystallinity of PTFE by twofold. Infrared spectroscopy (FTIR) studies confirmed that the main phenomenon associated with electron beam irradiation was the photodegradation of the polymer chains for both PTFE containing bronze and pure PTFE. This had a direct effect on the increase in the degree of crystallinity observed in DSC studies. The use of a bronze additive could lead to energy dissipation over the additive particles. An increase in hardness H and Young's modulus E was also observed. The addition of bronze and the irradiation with an electron beam improved of the operational properties of PTFE.

20.
Article in English | MEDLINE | ID: mdl-31878326

ABSTRACT

The aim of the research was to verify the functional state of young football players using selected tests of the Functional Movement Screen (FMS) protocol, as well as the impact of the 12 weeks of functional training on the speed parameters. The research was conducted on 20 highly competitive young (U17) football players. Research project was conducted in two stages: in the first part of the study, the functional assessment was made by using the FMS test, then the measurement of the speed parameters was done with the Microgate photocells system. Results showed a significant improvement in the functional state of young football players: FMS 1 (45.2% of difference, p = 0.004), FMS 2 (24.3% of difference, p = 0.012), FMS 3 (48.5% of difference, p = 0.001). After the functional training program, there was also an improvement in the parameters of the acceleration and velocity: acceleration between 5-10 m and speed between 10-30 m shows significant improvement (expressed during covering a given distance) of the footballers, amounting to 0.02 s (2.4%) and 0.04 s (1.5%). But there was no improvement in acceleration between 0-5 m. An appropriate training schedule, based on FMS results, should be adopted in the annual training program to improve basic motor skills of the football players and minimize their injuries.


Subject(s)
Acceleration , Exercise/physiology , Football , Motor Skills/physiology , Movement/physiology , Physical Functional Performance , Soccer , Adolescent , Humans , Male , Poland
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