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  • Author: Krzysztof Kaczmarczyk x
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Abstract

We hypothesized that the ACE ID / ACTN3 R577X genotype combination was associated with sprint and endurance performance. Therefore, the purpose of the present study was to determine the interaction between both ACE ID and ACTN3 R577X polymorphisms and sprint and endurance performance in swimmers. Genomic DNA was extracted from oral epithelial cells using GenElute Mammalian Genomic DNA Miniprep Kit (Sigma, Germany). All samples were genotyped using a real-time poly- merase chain reaction. The ACE I/D and the ACTN3 R577X genotype frequencies met Hardy-Weinberg expectations in both swimmers and controls. When the two swimmer groups, long distance swimmers (LDS) and short distance swimmers (SDS), were compared with control subjects in a single test, a significant association was found only for the ACE polymorphism, but not for ACTN3. Additionally, four ACE/ACTN3 combined genotypes (ID/RX, ID/XX, II/RX and II/XX) were statistically significant for the LDS versus Control comparison, but none for the SDS versus Control comparison. The ACE I/D and the ACTN3 R577X polymorphisms did not show any association with sprint swimming, taken individually or in combination. In spite of numerous previous reports of associations with athletic status or sprint performance in other sports, the ACTN3 R577X polymorphism, in contrast to ACE I/D, was not significantly associated with elite swimming status when considered individually. However, the combined analysis of the two loci suggests that the co-occurrence of the ACE I and ACTN3 X alleles may be beneficial to swimmers who compete in long distance races

Abstract

The method of unconventional solid rock loosening with undercutting anchors and the literature analysis of the problem are presented. The tests and test results of the rocks loosening process with a fixed undercutting anchor are described. The tests were carried out within the RODEST project, OPUS 10 competition No. 2015/19/B/ST10/02817, financed by the National Science Centre. Numerical modeling process as well as a series of laboratory and in situ tests were carried out. The test stand equipment and methodology for the in situ tests are presented. The tests were conducted in four mines, which allowed to obtain and determine the following characteristics:

  1. loosening force as a function of anchoring depth (for a given type of rock),
  2. the range of rock loosening in a function of anchoring depth (for a given type of rock), and
  3. loosened rock volume as a function of anchoring depth (for a given type of rock).

The in situ test results are compared with the concrete capacity design (CCD) model used for the calculation of anchor load capacity in concrete.

Abstract

Mining industry is currently one of the biggest industries in the world. All mines produce “indispensable” minerals, starting from fuels such as coal and ending with noble metals such as gold or copper. Mines in the world compete in the volumes of mined minerals what requires use of state-of-the-art, more efficient and, and what is more important, safer machines. Such trend favors development of technology and mobilize engineers to adapt the technologies that were used so far in easier environment to the needs of the mining industry.

The article presents the issue of energy recuperation in mining battery locomotives. Simulation tests of the power supply and control system of the Lea type battery locomotive are discussed. The results of tests on the electric energy consumption of the locomotive during the operational change in the mine were presented, which were referred to the simulation results. Factors influencing the efficiency of energy recovery and the risk resulting from hydrogen emission in the recuperation process have been indicated. Also discussed is the study of the concentration of hydrogen concentration emitted from the battery of lead-acid cells during their recharging in the process of electrical braking with energy recuperation.

Abstract

The purpose of this study was to examine the association of the BstUI RFLP C/T (rs 12722) and DpnII RFLP C/T (rs 13946) COL5A1 polymorphisms, individually and as haplotypes, with anterior cruciate ligament ruptures in recreational skiers. Subjects were 138 male recreational skiers with surgically diagnosed primary anterior cruciate ligament ruptures. The control group consisted of 183 apparently healthy male recreational skiers, who were without any self-reported history of ligament or tendon injury. DNA was extracted from buccal cells donated by the subjects and genotyping was carried out using real-time PCR. The genotype distributions for both polymorphisms met Hardy- Weinberg expectations in both groups. There were no significant differences in genotype distribution of allele frequencies of COL5A1 BstUI RFLP C/T and COL5A1 DpnII RFLP C/T polymorphisms between the ACL rupture and control groups. The T-T (BstUI RFLP T, DpnII RFLP T) haplotype was the most common (55.6%). The haplotype T-C was not present in any of the subjects. There was an underrepresentation tendency of the C-T haplotype in the study group compared to controls under recessive mode of inheritance. Higher frequency of the COL5A1 BstUI RFLP C/T and COL5A1DpnII RFLP C/T polymorphisms haplotype is associated with reduced risk of anterior cruciate ligament injury in a group of apparently healthy male recreational skiers.

Abstract

Collagen alpha-1(V) chain, encoded by the COL5A1 gene, plays a crucial role in abundant fibrillar collagens supporting many tissues in the body containing type I collagen and appears to regulate the association between heterotypic fibers composed of both type I and type V collagen occurring among others in muscles, tendons and ligaments. Taking this fact into consideration we decided to examine the association between COL5A1 rs12722 and rs13946 polymorphisms, individually and as inferred haplotypes, with anterior cruciate ligament rupture risk (ACLR) in professional soccer players. A total of 134 male professional soccer players with surgically diagnosed primary anterior cruciate ligament ruptures and 211 apparently healthy male professional soccer players, who were without any self-reported history of ligament or tendon injury, were included in the study. Both the cases and the healthy controls were recruited from the same soccer teams, of a similar age category, and had a comparable level of exposure to anterior cruciate ligament injury. Genomic DNA was extracted from oral epithelial cells using GenElute Mammalian Genomic DNA MiniprepKit. All samples were genotyped for the rs12722 and rs13946 polymorphisms using a Rotor-Gene realtime polymerase chain reaction. Statistically significant differences in the genotype frequencies for the COL5A1 rs13946 polymorphisms in dominant modes of inheritance occurred (p = 0.039). Statistically significant differences were documented only in the dominant model under the representation tendency of the C-C haplotype in the ACLR group compared to controls (p = 0.038). Our results suggest that variation in the COL5A1 gene may be one of the non-modifiable factors associated with the ACL injury in professional soccer players. The C-C rs12722-rs13946 haplotype provides a protective effect against the ACL tear.