Laboratory and Numerical Investigation of Pre-Tensioned Reinforced Concrete Railway Sleepers Combined with Plastic Fiber Reinforcement.

This research investigates the application of plastic fiber reinforcement in pre-tensioned reinforced concrete railway sleepers, conducting an in-depth examination in both experimental and computational aspects. Utilizing 3-point bending tests and the GOM ARAMIS system for Digital Image Correlation, this study meticulously evaluates the structural responses and crack development in conventional and plastic fiber-reinforced sleepers under varying bending moments. Complementing these tests, the investigation employs ABAQUS' advanced finite element modeling to enhance the analysis, ensuring precise calibration and validation of the numerical models. This dual approach comprehensively explains the mechanical behavior differences and stresses within the examined structures. The incorporation of plastic fibers not only demonstrates a significant improvement in mechanical strength and crack resistance but paves the way for advancements in railway sleeper technology. By shedding light on the enhanced durability and performance of reinforced concrete structures, this study makes a significant contribution to civil engineering materials science, highlighting the potential for innovative material applications in the construction industry.

Abiotic environmental factors drive the diversity, compositional dynamics and habitat preference of ectomycorrhizal fungi in Pannonian forest types.

Ectomycorrhizal (ECM) fungi are among the most diverse and dominant fungal groups in temperate forests and are crucial for ecosystem functioning of forests and their resilience toward disturbance. We carried out DNA metabarcoding of ECM fungi from soil samples taken at 62 sites in the Bükk Mountains in northern Hungary. The selected sampling sites represent the characteristic Pannonian forest types distributed along elevation (i.e., temperature), pH and slope aspect gradients. We compared richness and community composition of ECM fungi among forest types and explored relationships among environmental variables and ECM fungal alpha and beta diversity. The DNA sequence data generated in this study indicated strong correlations between fungal community composition and environmental variables, particularly with pH and soil moisture, with many ECM fungi showing preference for specific zonal, topographic or edaphic forest types. Several ECM fungal genera showed significant differences in richness among forest types and exhibited strong compositional differences mostly driven by differences in environmental factors. Despite the relatively high proportions of compositional variance explained by the tested environmental variables, a large proportion of the compositional variance remained unexplained, indicating that both niche (environmental filtering) and neutral (stochastic) processes shape ECM fungal community composition at landscape level. Our work provides unprecedented insights into the diversity, landscape-level distribution, and habitat preferences of ECM fungi in the Pannonian forests of Northern Hungary.

Investigation of a Ventilation System for Energy Efficiency and Indoor Environmental Quality in a Renovated Historical Building: A Case Study.

This paper emphasizes the importance of environmental protection regarding the reduction of energy consumption while maintaining living standards. The aim of the research is to observe the effects of mechanical and natural ventilation on energy consumption and building operation as well as indoor environmental quality (IEQ). The results of indoor environmental quality testing show that the mean relative humidity (31%) is in the permissible range (30%-70%); the mean CO2 concentration (1050.5 ppm) is above the recommended value of 1000 ppm according to Pettenkofer; and the mean PM10 concentration (43.5 µg/m3) is under the limit value of 50 µg/m3. A very large positive correlation is found between relative humidity and concentration of CO2 as well as between the concentration of PM5 and the concentration of CO2. The most commonly occurring sick building syndrome (SBS) symptoms are found to be fatigue and the feeling of a heavy head.

Optical measurement of the high temperature ballooning of nuclear fuel claddings.

During the last decades, several experiments revealed interesting details about the ballooning and burst of nuclear cladding tubes in accident conditions involving high temperature and high pressure. A new set of experiments was conducted at MTA EK to further improve our understanding of this phenomenon. The research goal was to determine the pressure of the burst at different temperatures. These data represent a durability and usability limit of fuel cladding tubes under loss of coolant accident conditions. A large tube furnace was fitted with two optical telescopes on opposite sides to observe the ballooning and burst of zirconium alloy fuel cladding samples. These telescopes gave an opportunity to capture the ballooning and also to use a high-speed camera to record details of the crack formation and crack propagation during the burst. A precise pressurization system was constructed to feed high-pressure argon into the samples at a given pressurization rate. The previous data were reproduced accurately in this new apparatus with further insight into the phenomena. The change in tube diameter was observed using regular HD cameras. Based on the captured images, an algorithmic method was developed to separate the contours of the cladding tubes from the background and the diameter increase was measured. It was found to be mostly uniform at lower pressures. The formation of a bulge started at 85% of actual burst pressure. Crack formation at high temperature was recorded using a high-speed camera at speeds up to 100.000 fps. The details of the planning, facility construction, and gauge calibration are detailed in this article.

Detection of sex chromosome aneuploidies using quantitative fluorescent PCR in the Hungarian population.

BACKGROUND: Aneuploidies are the most frequent chromosomal abnormalities at birth. Autosomal aneuploidies cause serious malformations like trisomy 21, trisomy 18 and trisomy 13. However sex chromosome aneuploidies are causing less severe syndromes. For the detection of these aneuploidies, the "gold standard" method is the cytogenetic analysis of fetal cells, karyograms show all numerical and structural abnormalities, but it takes 2-4 weeks to get the reports. Molecular biological methods were developed to overcome the long culture time, thus, FISH and quantitative fluorescent PCR were introduced. In this work we show our experience with a commercial kit for the detection of sex chromosome aneuploidies. METHODS: We analyzed 20.173 amniotic fluid samples for the period of 2006-2013 in our department. A conventional cytogenetic analysis was performed on the samples. We checked the reliability of quantitative fluorescent PCR and DNA fragment analysis on those samples where sex chromosomal aneuploidy was diagnosed. RESULTS: From the 20.173 amniotic fluid samples we found 50 samples with sex chromosome aneuploidy. There were 19 samples showing 46, XO, 17 samples with 46, XXY, 9 samples with 47, XXX and 5 samples with 47, XYY karyotypes. The applied quantitative fluorescent PCR and DNA fragment analyses method are suitable to detect all abnormal sex chromosome aneuploidies. CONCLUSIONS: Quantitative fluorescent PCR is a fast and reliable method for detection of sex chromosome aneuploidies.

Rapid determination of trisomy 21 from amniotic fluid cells using single-nucleotide polymorphic loci.

OBJECTIVES: Rapid detection of trisomy 21 is an important goal for prenatal genetic centers. Fluorescent-PCR and DNA fragment analysis was developed a decade ago and thousands of samples were analyzed in routine practice using this method. Quantitative real-time PCR with melting curve analysis using SNP markers for trisomy 21 detection was described recently. We studied the reliability of this method on a cohort of samples of Hungarian patients. METHODS: DNA was isolated with silica adsorption method from amniotic fluid cells. We investigated 67 trisomy 21 and 62 diploid samples in the study. Quantitative real-time PCR was performed using hybridization probes combined with melting curve analysis. Peak areas under the derivative curves were determined and analyzed. RESULTS: The SNP marker WIAF 899 was informative in 41.86% of cases and WIAF 2643 in 48.83%. The melting curve area ratios were significantly different between trisomic and normal cases for WIAF 899 (trisomic 0.5246 +/- 0.2498 vs 0.8347 +/- 0.5234; p < 0.001), while in the case of WIAF 2643, they were not different. CONCLUSION: Combined and selected SNP markers could be valuable tools for rapid trisomy 21 detection in prenatal genetic screening.

[The most important sources of the Graeco-Arabic medicine]. / A görög-arab medicina dietétikájának legfontosabb forrásai.

The author gives a comprehensive guide to Hungarian scholars, who attempt to search the history of Graeco-Arabic medicine and dietetics, respectively. This guide contains a short introduction into the different types of sources, lists the main authors, editions and texts available in Hungary indicating the libraries where the sources are to be found. The author organizes his material according the the main authors of the subject. Helped by this useful "database" researchers might be able to avoid difficulties of the first steps on this still, actually, largely unexplored field of the history of medicine .