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The present study applies the discontinuous Galerkin finite element method to a numerical simulation of a compressible fluid flow through a labyrinth seal. This paper is proposes a curvilinear hexahedral element, which is deformed in such a way that it matches the rotated walls of the labyrinth seal exactly. A numerical study is performed on the staggered labyrinth seal with two teeth on the rotor and one tooth on the stator. For numerical simulation, three computational meshes with different refinement are considered. All of the numerical simulations are performed for both stationary rotor and for rotor rotating at 50 Hz. The obtained numerical results are compared with results computed by the commercial CFD software Ansys Fluent.

Due to insufficient appreciation for the breeding of dairy sheep, breeds of sheep without market milk production have started to gain popularity in Slovakia. Particularly, meat breeds are coming to the forefront, with their breeding being less demanding and more efficient, reflected mainly in the daily weight gains of growing lambs. Study aimed to analyse the utility and reproductive parameters of breeding the meat breeds Suffolk, located in central Slovakia, in the Rimavská Sobota district. Analysis is supplemented by a detailed description of the breed standard and devotes attention to all the tasks carried out on the farm during the sheep farming year. It focuses mainly on a simple year-round grazing system without housing, utilizing only shelters for protection against adverse weather conditions. Analysed utility and reproductive parameters such as average daily gains, loin muscle thickness, backfat thickness, and fertility were compared and evaluated over the last seven years. Results indicate that the evaluated parameters are mainly influenced by the size of the flock, the number of ewes put to ram, the individual approach to each breeding ewe, and environmental factors. Number of offspring is mainly influenced by the nutrition of the dam in the last third of pregnancy. Despite the simplicity of the breeding system, monitored breeding can achieve above-average results with proper management and innovative approaches.

Background: Improved technologies for chromatin accessibility sequencing such as ATAC-seq have increased our understanding of gene regulation mechanisms, particularly in disease conditions such as cancer. Methods: This study introduces a computational tool that quantifies and establishes connections between chromatin accessibility, transcription factor binding, transcription factor mutations, and gene expression using publicly available colorectal cancer data. The tool has been packaged using a workflow management system to allow biologists and researchers to reproduce the results of this study. Results: We present compelling evidence linking chromatin accessibility to gene expression, with particular emphasis on SNP mutations and the accessibility of transcription factor genes. Furthermore, we have identified significant upregulation of key transcription factor interactions in colon cancer patients, including the apoptotic regulation facilitated by E2F1, MYC, and MYCN, as well as activation of the BCL-2 protein family facilitated by TP73. Conclusion: This study demonstrates the effectiveness of the computational tool in linking chromatin accessibility to gene expression and highlights significant transcription factor interactions in colorectal cancer. The code for this project is openly available on GitHub.

The widespread adoption of the Internet of Things (IoT) partly depends on the successful design and deployment of IoT nodes that can operate for several years without any service outage and the need to replace their energy storage systems (ESSs) (e.g., battery, capacitor, or supercapacitor) when all the stored energy is depleted or when the cycle life of the ESSs is reached. Replacing batteries in the case of large-scale IoT networks and nodes located in places that are hard to reach is very challenging and costly, requiring the design of IoT nodes that can operate for several years without the need for human intervention. One such example is the deployment of IoT nodes in large agricultural fields (for soil or crop monitoring) or a long-distance pipeline (for pipeline monitoring). In this paper, we investigated the practical implications of imposing energy-saving thresholds on the energy performance metrics of green IoT nodes. We propose an energy packet-based model for the evaluation of the energy performance of a green IoT node with the possibility of switching the node to energy-saving regimes on the fly when the energy content of the ESS reaches defined thresholds. Configuring single or multiple thresholds improves the energy performance of the node significantly (e.g., increases the lifetime of the node and reduces the probability of service outage and energy wastage), and the value of the threshold(s) should be carefully chosen. The energy performance of the IoT node can also be improved by dimensioning the energy harvesting system to ensure that the node operates for several years without running out of energy (e.g., maximizing the lifetime of the nodes and minimizing the probability of service outage and energy wastage).

In this paper, a numerical simulation and experimental measurements of compressible viscous fluid flow in simplified blade cascade are compared. The cascade consists of five flat plates three of which perform prescribed harmonic motion. The computed unsteady velocity field is compared with experimental measurements at selected points. Moreover, the power spectral density corresponding to the frequency of harmonic motion is computed for both the numerical and experimental data and compared. The numerical simulation was performed using the developed in-house CFD software based on the discontinuous Galerkin method, which offers high order of accuracy.

AbstractAnalysis of the qualitative signature of fatty acids in tissues of organisms is an increasingly utilized tool in studies of trophic ecology in aquatic and terrestrial ecosystems. Here, we studied a colonial waterbird, the black-headed gull Chroicocephalus ridibundus, nesting in three colonies. We aimed to investigate whether fatty acid composition of its eggs is affected by the location of the colony (reflecting the spatial variation in habitat composition and, in turn, female diet at the time of egg formation), and the egg laying sequence (reflecting the temporal variation in female diet). We found that the composition of fatty acids in eggs of black-headed gulls differed among colonies, but not among subsequent eggs within the clutch. We interpret these results in the context of spatial differences in the diet of females breeding in different colonies and a lack of temporal variation in the diet of individual females. The pattern of the ratio of omega-3 to omega-6 fatty acids reflected the contribution of aquatic/terrestrial prey to their diet, and was consistent with the area of water courses around the colonies. High levels of omega-6:omega-3 can promote inflammation and thus lead to increased susceptibility to antigens. Further studies with prey sampling are required to reconstruct the diet composition of females during egg formation in more detail.

Reducing the emission of global warming gases currently remains one of the strategic tasks. Therefore, the objective of our work was to determine the effect of saponite clay on fermentation in the rumen of cows. The pH, total gas production, CH4, and volatile fatty acid (VFA) production in ruminal fluid was determined in vitro. Saponite clay from the Tashkiv deposit (Ukraine) has a high content of silicon, iron, aluminum, and magnesium. The addition of 0.15 and 0.25 g of saponite clay to the incubated mixture did not change the pH but reduced the total production (19% and 31%, respectively) and CH4 (24% and 46%, respectively) in the ruminal fluid compared to the control group and had no significant effect on the total VFA levels, but propionic acid increased by 15% and 21% and butyric acid decreased by 39% and 32%, respectively. We observed a decrease in the fermentation rates, with a simultaneous increase in the P:B ratio and an increase in the fermentation efficiency (FE) in the groups fermented with saponite clay, probably a consequence of the high efficiency in the breakdown of starch in the rumen. Therefore, further in vivo studies to determine the effective dose and effect of saponite clay on cow productivity and the reduction of gas emissions are promising and important.

The widespread adoption of the Internet of Things (IoT) partly depends on the successful design and deployment of IoT nodes that can operate for several years without any service outage and the need to replace their energy storage systems (ESSs) (e.g., battery, capacitor, or supercapacitor) when all the stored energy is depleted or when the cycle life of the ESSs is reached. Replacing batteries in the case of large-scale IoT networks and nodes located in places that are hard to reach is very challenging and costly, requiring the design of IoT nodes that can operate for several years without the need for human intervention. One such example is the deployment of IoT nodes in large agricultural fields (for soil or crop monitoring) or a long-distance pipeline (for pipeline monitoring). In this paper, we investigated the practical implications of imposing energy-saving thresholds on the energy performance metrics of green IoT nodes. We propose an energy packet-based model for the evaluation of the energy performance of a green IoT node with the possibility of switching the node to energy-saving regimes on the fly when the energy content of the ESS reaches defined thresholds. Configuring single or multiple thresholds improves the energy performance of the node significantly (e.g., increases the lifetime of the node and reduces the probability of service outage and energy wastage), and the value of the threshold(s) should be carefully chosen. The energy performance of the IoT node can also be improved by dimensioning the energy harvesting system to ensure that the node operates for several years without running out of energy (e.g., maximizing the lifetime of the nodes and minimizing the probability of service outage and energy wastage). [ABSTRACT FROM AUTHOR]

Water deficit is one of the most important stress factors affecting yield and production quality. Breeders are focusing on breeding wheat cultivars and crop lines that are more resistant to water deficit, so there is a possibility that plants with changes in their ear morphologies, such as long chaff and multi-rowed varieties, will be more resistant to water deficit. Therefore, our research focused on the study of changes in the physiological parameters of wheat cultivar ‘Bohemia’ (normal cob) with an altered morphotype (genotypes ‘284-17’ (long chaff) and genotype ‘29-17’ (multirow cob)), in relation to the duration of the water deficit. The experiment was set up as a container experiment under partially controlled greenhouse conditions. The experimental design included four treatments. The control (C) variant was irrigated regularly. The other treatments were stressed by water deficit, which was induced through the method of gradually drying the substrate: treatment D1 involved 10 days without irrigation, 4 days of watering, 10 days with a re-induced water deficit and 4 days of watering; treatment D2 involved 10 days of watering, and then stress was induced via water deficit until the end of the experiment; treatment D3 involved 10 days of stress and then irrigation until the end of the experiment. The pigment content, gas exchange rate, chlorophyll fluorescence and water potential were monitored in the juvenile wheat plants. The obtained results showed that the contents of photosynthetically active pigments (chlorophyll a and b and carotenoids) were influenced by the gene type. The chlorophyll and carotenoid content were higher in genotype ‘29-17’ (0.080 and 1.925 nM cm−2, respectively) and lowest in cultivar ‘Bohemia’ (0.080 and 0.080 nM cm−2, respectively). The chlorophyll content decreased due to water deficit most significantly in the D2 variant (0.071 nM cm−2), compared to the control (0.138 nM cm−2). The carotenoid content significantly decreased due to water deficiency in the cultivar ‘Bohemia’, D2 (0.061 nM cm−2) and the genotype ‘284-17’ (0.075 nM cm−2) and non-significantly decreased in ‘29-17’ (1.785 nM cm−2). In the control plants, the carotenoid content decreased in the following order: genotype ‘29-17’ (1.853 nM cm−2) > genotype ‘284-17’ (0.088 nM cm−2) > cv. ‘Bohemia’ (0.087 nM cm−2). Wheat plants had a decreased photosynthetic rate due to the closure of stomata and reduction in substomatal CO2 levels, which were caused by water deficit. The above effect was observed in genotype ‘29-17’ and cultivar ‘Bohemia’. The transpiration rate increased by 0.099 mM m−2 s−1 (5.69%) in the variety ‘Bohemia’, due to water deficit. On the other hand, the transpiration rate of genotype ‘29-17’ and genotype ‘284-17’ decreased by 0.261 mM m−2 s−1 (88.19%) and 0.325 mM m−2 s−1 (81.67%), respectively, compared to the control. Among the genotypes studied, genotype ‘29-17’ showed higher photosynthesis and transpiration rates, compared to genotype ‘284-17’ and the variety ‘Bohemia’. The effect of genotype and water deficit on chlorophyll fluorescence parameters was also shown. In all genotypes studied, there was a significant decrease in water potential due to water deficit, most significantly in the Bohemia variety, then in the genotype ‘284-17’, and the least significant decrease in water potential was seen in the genotype ‘29-17’. Genotype ‘29-17’ appears promising with respect to drought tolerance and photosynthetic rate, despite increased transpiration and reduced water potential; it also appears promising for better water management, with respect to reduced water potential in aboveground organs. On the other hand, the variety Bohemia appears to be less suitable for dry areas, since, despite its relative plasticity, it shows not only high water potential values in the water deficit region but also the most significant decrease in water potential.

The ability to localize a sound source in complex environments is essential for communication and navigation. Spatial hearing relies predominantly on the comparison of differences in the arrival time of sound between the two ears, the interaural time differences (ITDs). Hearing impairments are highly detrimental to sound localization. While cochlear implants (CIs) have been successful in restoring many crucial hearing capabilities, sound localization via ITD detection with bilateral CIs remains poor. The underlying reasons are not well understood. Neuronally, ITD sensitivity is generated by coincidence detection between excitatory and inhibitory inputs from the two ears performed by specialized brainstem neurons. Due to the lack of electrophysiological brainstem recordings during CI stimulation, it is unclear to what extent the apparent deficits are caused by the binaural comparator neurons or arise already on the input level. Here, we use a bottom-up approach to compare response features between electric and acoustic stimulation in an animal model of CI hearing. Conducting extracellular single neuron recordings in gerbils, we find severe hyper-precision and moderate hyper-entrainment of both the excitatory and inhibitory brainstem inputs to the binaural comparator neurons during electrical pulse-train stimulation. This finding establishes conclusively that the binaural processing stage must cope with highly altered input statistics during CI stimulation. To estimate the consequences of these effects on ITD sensitivity, we used a computational model of the auditory brainstem. After tuning the model parameters to match its response properties to our physiological data during either stimulation type, the model predicted that ITD sensitivity to electrical pulses is maintained even for the hyper-precise inputs. However, the model exhibits severely altered spatial sensitivity during electrical stimulation compared to acoustic: while resolution of ITDs near midline was increased, more lateralized adjacent source locations became inseparable. These results directly resemble recent findings in rodent and human CI listeners. Notably, decreasing the phase-locking precision of inputs during electrical stimulation recovered a wider range of separable ITDs. Together, our findings suggest that a central problem underlying the diminished ITD sensitivity in CI users might be the temporal hyper-precision of inputs to the binaural comparator stage induced by electrical stimulation.

Background: Improved technologies for chromatin accessibility sequencing such as ATAC-seq have increased our understanding of gene regulation mechanisms, particularly in disease conditions such as cancer. Methods: This study introduces a computational tool that quantifies and establishes connections between chromatin accessibility, transcription factor binding, transcription factor mutations, and gene expression using publicly available colorectal cancer data. The tool has been packaged using a workflow management system to allow biologists and researchers to reproduce the results of this study. Results: We present compelling evidence linking chromatin accessibility to gene expression, with particular emphasis on SNP mutations and the accessibility of transcription factor genes. Furthermore, we have identified significant upregulation of key transcription factor interactions in colon cancer patients, including the apoptotic regulation facilitated by E2F1, MYC, and MYCN, as well as activation of the BCL-2 protein family facilitated by TP73. Conclusion: This study demonstrates the effectiveness of the computational tool in linking chromatin accessibility to gene expression and highlights significant transcription factor interactions in colorectal cancer. The code for this project is openly available on GitHub. [ABSTRACT FROM AUTHOR]

Our perception is based on active sensing, i.e., the relationship between self-motion and resulting changes to sensory inputs. Yet, traditional experimental paradigms are characterized by delayed reactions to a predetermined stimulus sequence. To increase the engagement of subjects and potentially provide richer behavioral responses, we developed Sensory Island Task for humans (SITh), a freely-moving search paradigm to study auditory perception. In SITh, subjects navigate an arena in search of an auditory target, relying solely on changes in the presented stimulus frequency, which is controlled by closed-loop position tracking. A “target frequency” was played when subjects entered a circular sub-area of the arena, the “island”, while different frequencies were presented outside the island. Island locations were randomized across trials, making stimulus frequency the only informative cue for task completion. Two versions of SITh were studied: binary discrimination, and gradual change of the stimulus frequency. The latter version allowed determining frequency discrimination thresholds based on the subjects’ report of the perceived island location (i.e., target frequency). Surprisingly, subjects exhibited similar thresholds as reported in traditional “stationary” forced-choice experiments after performing only 30 trials, highlighting the intuitive nature of SITh. Notably, subjects spontaneously employed a small variety of stereotypical search patterns, and their usage proportions varied between task versions. Moreover, frequency discrimination performance depended on the search pattern used. Overall, we demonstrate that the use of an ecologically driven paradigm is able to reproduce established findings while simultaneously providing rich behavioral data for the description of sensory ethology.

Although fiber-reinforced polymers (FRPs) have achieved increasing popularity in strengthening concrete structures and reinforcing new ones, there is to date insufficient knowledge about their long-term behavior. The long-term properties of FRPs specified in design codes lead to the low utilization capacity of these materials and are not supposed to be correct according to the actual behavior of structures reinforced with FRPs after 20 or 30 years of their use. Environmental impact reduction factors limit the mechanical properties of FRP composites in a range from 0.95 for CFRP to 0.5 for GFRP; the creep rupture factor is from 0.9 to 0.2. The paper summarizes previous research and experimental studies on the long-term properties of FRP reinforcements and also their comparison with the actual structures in which this reinforcement has been used; it presents the first part of an experimental investigation with comparative calculations.

Given growing concerns about the use of antibiotics in the treatment of animals, identifying organic alternatives as feed additives to improve animal health and the development of immune responses has become of interest in dairy farming. Humic acids (HA) seem to be a suitable alternative with a favorable impact on the health and production parameters of animals. This study aimed to determine the effects of an HA supplemented diet on milk parameters as well as the effects on somatic cell count (SCC) and the occurrence of mastitis in dairy cows during the peripartum period. Twenty dairy cows in the last stage of pregnancy were selected from a herd of 140 cows. The selected cows were randomly divided into two groups: control (C) and experimental (E). The two groups were fed the same feed mixture and group E was additionally supplemented with HA at a total dose of 100 g per cow per day during the last 50 days of pregnancy. The milk parameters (dry matter, lactose, fat, crude protein, casein and milk urea) and SCC of every cow, and the presence of mastitis, were checked on days 10 and 30 during the first month of lactation. The results of the study show that dietary supplementation with HA significantly reduced the milk urea (MU) content and SCC on the 10th day after calving but did not affect the other milk compositions. In addition to the decreased MU and SCC, the number of positive quarters detected by the California Mastitis Test was reduced by 20.0% and the occurrence of mastitis caused by coagulase-negative staphylococci (CNS). Based on the obtained results we can conclude that the addition of HA stabilizes the nutrient digestion, as was confirmed by a reduced MU content in the supplemented group. Their indirect beneficial effects improved the development of immune responses, resulting in decreased SCC and the occurrence of mastitis caused by CNS.

This study aimed to analyse changes in the profile of long-chain fatty acids in the ruminal fluid of cows during in vitro fermentation, using different proportions of maize DDGS (distillers dried grains with solubles) as a substrate. The serum bottles were filled with 1 g of concentrate feed (C), which consisted of cereal middlings, postextraction rapeseed meal, and soybean meal. Substrates I, II, and III contained the same ingredients as substrate C, but also included DDGS at increasing proportions, while substrate IV contained only DDGS. Ruminal fluid with a buffer was then added to the bottles and incubated for 4, 8, and 24 h. After incubation, the fatty acid profile was analysed using a gas chromatograph. The use of DDGS as a substrate resulted in a decrease in SFA, and an increase in the proportion of UFA, including oleic acid (C18:1n9c) and linoleic acid (C18:2n6c). The fermentation profile with 15% and 20% DDGS in TMR proved to be the most beneficial. These findings suggest that the byproduct of bioethanol production could potentially improve the fatty acid profile in the ruminal fluid, resulting in higher-quality animal products.