Flow cytometry application in the assessment of sperm DNA integrity of men with asthenozoospermia.

Sperm genomic integrity and ultrastructural features of ejaculated spermatozoa contributing to the assessment of gamete fertility potential in patients with asthenozoospermia are discussed. The proportion of TUNEL-positive cells was significantly higher in the semen of patients with low sperm motility (n=40; p4% of TUNEL-positive sperm cells. Low sperm motility seems to be accompanied by serious defects of gamete chromatin expressed as diminished sperm genomic integrity and abnormal DNA condensation and by defects of sperm midpiece. These abnormalities may reflect developmental failure during the spermatogenic remodeling process. The DNA fragmentation test may be considered as an additional assay for the evaluation of spermatozoa beside standard analysis and taken together with electron microscopy may help to determine the actual number of "healthy" spermatozoa thereby playing an important role during diagnosis and treatment of male infertility

Evaluation of the Technological Properties of the Al-Si Eutectic Alloy Based on Density Index Test

Aluminium-silicon alloys are widely used in industrial practice due to their many advantages, including light weight and relatively high strength. The consumption of these light engineering materials is constantly increasing, especially in the automotive industry, due to new greenhouse gas (GHG) emission standards. The sustainable development strategy in the foundry industry is related to reducing the amount of waste and pollution generated during the production process. In turn, reducing the number of production shortages and waste requires the production of good quality Al-Si castings, and thus the appropriate selection and monitoring of technological parameters affecting the quality of the liquid alloy, including the level of purity and the degree of its gasification. The main objective of the research conducted to evaluate the technological properties of the AlSi12CuNiMg (AlSi12) alloy was to identify the causes of increased defect rates in piston castings during the production process at the Złotecki Sp. z o.o. The tests were carried out using two Al-Si alloys with silicon content close to eutectic (approx. 12%) used for piston castings, from two different suppliers. Three measurement methods were used to evaluate the technological properties of the tested AlSi12 alloys: thermal analysis, fluidity test and density index for gasification measurement. Based on the analysis of the results, it was concluded that an excessively low-density index level might be the cause of the increased casting defect rates observed in the production of pistons for internal combustion engines and compressors, particularly for castings with significant variations in wall thickness

The aerodynamic assessment of tandem cyclists in preparation for the 2021 Paralympic Games: A case study.

Reducing the level of aerodynamic drag (CdA) via use of a wind tunnel will ultimately improve a competitive cyclists performance. Whilst this tool is widely considered a ‘gold standard’, previous studies have centered on single riders or scale models to evaluate aerodynamic drag. No study to date has assessed the precision of wind tunnel testing with the additional perceived complexity of a tandem bicycle with a pair of competitive paracyclists. The first part of this investigation evaluated the use of a wind tunnel in the assessment of tandem paracyclists. A male and female team of paracyclists riding tandem versions of either a time trial track bicycle or a road/time trial bicycle undertook a series of measurement intervals in a wind tunnel. Three different combinations of these riders and bicycles obtained a Coefficient of Variation of their mean CdA of 1.8-2.6%. The second part of this investigation acted as a case study by implementing a range of aerodynamic interventions to potentially reduce the male team’s CdA. For example, progressive efforts reduced a team’s CdA from the baseline of 0.338 m2 to ultimately 0.321 m2 predominately by lowering both tandem riders heads Whilst tandem cyclist performance enhancement has recieved scant attention in the past, this case study only highlights the value of doing so in the future

Total hemoglobin mass, aerobic capacity, and hbb gene in polish road cyclists

The relationship between genes, amount of hemoglobin, and physical performance are still not clearly defined. The aim of this study was to examine the association between-551C/T and intron 2, +16 C/G polymorphisms in the beta hemoglobin (HBB) gene and total hemoglobin mass (tHbmass) and aerobic capacity in endurance athletes. Total hemoglobin mass and aerobic capacity indices, i. e.,VO2max, oxygen uptake at anaerobic threshold (VO2AT), maximal power output (Pmax), and power at anaerobic threshold (PAT) were determined in 89 young road cyclists, female (n = 39) and male (n = 50), who were genotyped for 2 polymorphisms in the HBB gene. The relative values of aerobic capacity indices differed significantly among intron 2, +16 C/G polymorphisms of the HBB gene only in female cyclists; athletes with GG genotype had significantly higher values of V O2max (p = 0.003), VO2AT (p = 0.007), PAT (p = 0.015), and Pmax (p = 0.004) than C carriers. No relationships were found between the C-carrier model (CC + CG vs. GG in the case of intron 2, +16 C/G and CC + CT vs. TT for -551 C/T polymorphisms of the HBB gene) and relative values of tHbmass. Our results demonstrated that the HBB gene could be related to aerobic capacity, but it seems that it does not result from an increase in the amount of hemoglobin in the blood