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This work aims to present the results of evaluating the coloristic properties of polylactic acid (PLA) fibers. PLA is common nowadays in much research, as it is a biodegradable plastic from renewable sources. However, little research is devoted to PLA fibers, and even less to applied research of colored fibers. The prepared color masterbatches, created using inorganic pigments, such as titanium dioxide and carbon black, were subsequently used to prepare dyed PLA fibers in mass. The fibers were drawn to the maximum drawn ratio. The properties of the pure and dyed fibers were investigated before and after accelerated light aging using Q-SUN equipment. The changes were recorded by Fourier Transform Infrared (FTIR) spectroscopy and colorimetric properties were recorded using a device spectrometer from TECHKON SpectroDens. We also evaluated thermal properties from the first heating via differential scanning calorimetry (DSC). The measurements were taken before and after the aging of the PLA fibers, in order to see the effect of aging on the supermolecular structure, excluding the influence of the preparation process and the influence of the kind of PLA. Using inorganic pigments showed sufficient color stability even after accelerated light aging, which is beneficial for using colored fibers in practice.

In the past, mill races were part of the urban structure of many towns in Slovakia. As regulated and artificially created waterways, they served to drive mills, rollers, or hammers. With the use of new sources of energy, they lost their functions, and most of them were dried, filled, or buried underground. In our research, we examine the former mill race corridor in Podolínec (Prešov region, Slovakia) and its potential to contribute to urban regeneration strategies. The research steps included the following, namely 1. Identification of the route of the mill race corridor according to historical sources, 2. survey of its current state and its spatial preservation in the urban structure, 3. evaluation of the possibilities of its new uses, which could increase the quality and attractiveness of urban public spaces. The research results show that the fragments of the corridor of the extinct mill race are still identifiable in the urban fabric, and in the cadaster, they are in public ownership and suitable for new uses. The fragments of the corridor of the extinct mill race in Podolínec represent a potential for strengthening the blue and green infrastructure, pedestrian and cycling greenways, and a potential for the presentation of cultural heritage values, which could contribute to the improvement of the qualities of the urban environment.

Abstract Daily oscillations are present in many aspects of the immune system, including responsiveness to infections, allowing temporal alignment of defence mechanisms with the external environment. Our study addresses whether compromised circadian timing function by dim artificial light at night (ALAN) impacts the time dependency of the acute inflammatory response in a rat model of lipopolysaccharide (LPS)-induced inflammation. After 2 weeks of exposure to low-intensity ALAN (~2 lx) or a standard light/dark cycle, male rats were challenged with LPS during either the day or the night. Dim ALAN attenuated the anorectic response when rats were stimulated during their early light phase. Next, ALAN suppressed daily variability in inflammatory changes in blood leukocyte numbers and increased the daytime sensitivity of neutrophils to the priming effects of LPS on oxidative burst. An altered renal inflammatory response in ALAN-exposed rats was manifested by stimulated T-cell infiltration into the kidney upon night-time LPS injection and the modified rhythmic response of genes involved in inflammatory pathways. Moreover, ALAN disturbed steady-state oscillations of the renal molecular clock and eliminated the inflammatory responsiveness of Rev-erbα. Altogether, dim ALAN impaired time-of-day-dependent sensitivity of inflammatory processes, pointing out a causal mechanism between light pollution and negative health effects.

The study's main objective is the possible application of regranulate based on PLA and PHB bioplastics in the FDM 3D printing technique. The idea of using regranulate in the tested PLA/PHB biodegradable polymer blend can help to reduce the amount of plastic waste produced after defective or unwanted 3D printing from these types of materials suitable for 3D printing or after the industrial production of filaments with inadequate geometric parameters, which may help to economize raw material resources and, ultimately, lower the cost of studied polymer materials producing. The regranulate was added to the non-recycled biodegradable polymer blend with the same chemical composition in two different processes for making the filament for 3D printing. Based on testing the processing and utility properties of the processed regranulate materials, it was found that the regranulate partially degrades during multiple processing and thereby reduces the average molar mass and viscosity of the tested material during its processing. However, it was proven that despite the reduction of molecular characteristics after regranulate additions, it was possible to prepare the filaments by both investigated technologies of the regranulate addition and subsequently, it was possible to print such filaments using FDM 3D printing technology, even when the polymer blend contained a high content of regranulate. It was also proven that PLA/PHB materials containing regranulate exhibit comparable thermophysical and strength characteristics to the virgin PLA/PHB polymer blend.

The subject of the presented article is the analysis of the spatial planning legislation that is currently valid and effective and its comparison with the spatial planning legislation that will come into effect on April 1, 2024, in the legal conditions of the Slovak Republic. The authors of the article focused primarily on the comparison of two basic spatial planning tools – spatial planning documents and spatial planning documentation. The issue of the spatial plan of the municipality is elaborated in more detail, while the article points to changes in its legal regulations in connection with the process of land consolidation and the battle against climate change.

Urban overheating, intensified by climate change, poses a critical challenge in Central European cities, witnessing a rise in tropical days. Conventional mechanical cooling systems in buildings significantly contribute to carbon dioxide emissions, exacerbating global warming. In response, windcatchers—traditional Iranian natural cooling systems—emerge as a promising sustainable solution for contemporary architecture, even in non-arid climates. This research aims to evaluate windcatchers’ efficacy in improving building thermal comfort in Central European climates, focusing on Vienna’s urban environment. This study identifies optimal windcatcher designs by analyzing key variables: height variation, inlet dimensions, urban exposure, Building Management System (BMS) temperature thresholds, and integration with an earth tube system using Design Builder simulation software version 6. The findings reveal that a windcatcher standing at 2.5 m tall, with inlet dimensions of 0.9 m by 1.4 m, in an open, less densely populated urban setting, and with open valves when indoor temperatures surpass 22 °C, demonstrates the most effective reduction in cooling load. Moreover, both one-sided and two-sided windcatchers outperform conventional ventilation through openings. Additionally, combining a one-sided windcatcher with an earth tube system ensures efficient cooling even when exterior temperatures exceed 25 degrees Celsius. When augmented by a heat pump, this integrated system can provide heated ventilation.

In recent years, communication using electromagnetic (EM) radiation became an integral part of our lives. As a result, there is a large number of base transceiver stations (BTSs) which act as a source of high EM exposure for inhabitants mainly in the “hot-spot” areas. They employ higher values of radiation, thus, providing potentially harmful effects on living or working environment. The aim of this pilot study was to study a distribution of hot-spots and EMF power in a vicinity of BTSs. BTS was located in an extra-village area at least 500 m away from the nearest city or surrounded villages in the district of Martin. The targeted area of EM radiation from the BTS was divided into two smaller zones, the right and the left. For a better visualization, topographic maps were created. Using spectral analyzer Aaronia Spectran HF-6085, intensities of EMF within the frequency range from 880 – 960 MHz (GSM900) were recorded. Maximum values of EMF power flux density were 146.827 μW/m2 in horizontal and 96.448 μW/m2 in vertical plane. Minimal va lues were 0.052 μW/m2 in horizontal and 0.179 μW/m2 vertical plane respectively. The maps revealed two hotspots in the left zone and also two (smaller and larger) hotspots in the right zone. Our values were below the actual limits given by the Slovak Republic and the International Commission for Non-Ionizing Radiation Protection (ICNIRP) safety guidelines. However, the values from the hotspots were above the limits suggested by the BioInitiative Report. Our results indicate an elevation of EMF values in the hot-spots even in the extra-village areas. Further studies are needed to analyze in detail EMF parameters in the hot-spots, and their effects on living and working environments.

The research aimed to investigate the variability of the acrylamide content in French potato fries depending on the type of oil and the length and conditions of deep-frying. Deep-frozen pre-fried potato French fries primarily intended for catering establishments were deep-fried parallel in two oils (multi-component oil and rapeseed oil) at the same conditions (175 °C/4 min and 200 °C/3 min) until the limit for total polar compounds (TPCs) content (24%) was reached. The samples were analysed immediately after removal from the package, after the first frying and when the TPCs was exceeded. High-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC/ESI-MS/MS) was used to determine acrylamide. Mathematical and statistical evaluation of the results was according to the indicators of descriptive characteristics, i.e., arithmetic mean, standard deviation (SD), and coefficient of variation (%). Analysis of variance (ANOVA) was used to compare groups, i.e., the assumption of agreement of variance was verified by the F test (F). All pairwise differences in means were tested using Tukey's HSD test (Honest Significantly Different) and Scheffe´s test. The critical value of α, compared to the standardized difference between the means, was established using our chosen risk of 5%. The highest acrylamide values were measured in samples deep-fried in rapeseed oil at 200 °C/3 min in sample 2b (451.13 µg/kg when deep-fried immediately) and in sample 2d (383.24 µg/kg after exceeding TPCs). The lowest values of acrylamide were found in samples deep-fried in multi-component oil at a temperature of 200 °C/3 min in sample 1d (183.35 µg/kg after exceeding TPCs) and at a temperature of 175 °C/4 min in sample 1c (240.75 µg/kg after exceeding TPCs). The decreased tendency of acrylamide in both types of oils and variants of temperature after exceeding TPCs compared to the state immediately after frying is confirmed for all samples. Potato-based products are a significant source of acrylamide production and subsequent consumption. Monitoring its presence in food is, therefore, an important legislative requirement.

Sea buckthorn pomace is a by-product of juice production, which is still rich in bioactive compounds. After drying, the pomace can be effectively used as a valuable addition to bakery products supporting their nutritional value. However, due to the high content of the amino acid asparagine in sea buckthorn, this promising material contributes to the undesirable formation of acrylamide. To reduce the risk from this potentially carcinogenic compound, enzymatic treatment of sea buckthorn with asparaginase was applied, which resulted in a substantial reduction of asparagine content from 1834 mg/kg in untreated dried sea buckthorn pomace to 89 mg/kg in enzymatically treated dried sea buckthorn pomace. 10% substitution of wholegrain cereal flour with enzymatically treated sea buckthorn pomace powder in rye and triticale biscuits resulted in a 35% reduction in acrylamide content, in the case of wholegrain wheat biscuits up to a 64% reduction, compared to biscuits with untreated sea buckthorn pomace powder. This study confirmed that treating fruit with asparaginase is an effective way to reduce health risk caused by acrylamide in biscuits enriched with nutritionally valuable fruit pomace.

In this research the meat quality of the two canary sheep local breeds, Canaria breed (CB) and Canaria Hair breed (CHB), was evaluated, making groups of 10 males and females from each, slaughtered at live weights of 9.78 ± 0.49 kg, 15.8 ± 0.66 kg and 24.9 ± 0.76 kg. The breed affected to meat and fat colour at 24 h after slaughter. Meat of CB showed more redness and more chroma values. Fat of CB showed greater lightness. Related to the physio-chemical analysis of the meat, CB showed higher water-holding capacity, shear force and intramuscular fat content that CHB; however, CHB showed higher protein and ash percentages that CB. In relation to fat quality, CB presented higher MUFA percentage and CHB had higher PUFA percentage. CHB showed the lower atherogenic and thrombogenic indexes. Slaughter weight affected the pH, meat and fat colour and also all physio-chemical parameters, except shear force and collagen content and the fatty acid profile. Males had higher moisture content, soluble collagen and PUFA, while females had higher MUFA. The breed effect on meat quality was shown mainly in lambs slaughtered at 10 kg. Owing to their fatty acid profile, the healthiest meat was from lambs slaughtered at 25 kg. [ABSTRACT FROM PUBLISHER]