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Basic raw materials belong to the key input sources in the production of pig iron. The properties of basic raw materials can be evaluated using a variety of criteria. The essential ones include the physical and chemical properties. Current competitive pressures, however, force the producers of iron more and more often to include cost and logistic criteria into the decision-making process. In this area, however, they are facing a problem of how to convert a variety of vastly different parameters into one evaluation indicator in order to compare the available raw materials. This article deals with the analysis of a model created to evaluate the basic raw materials, which was designed as part of the research. [ABSTRACT FROM AUTHOR]

The ability to optimize costs plays a key role in maintaining competitiveness of the company, because without detailed knowledge of costs, companies are not able to make the right decisions that will ensure their long-term growth. The aim of this article is to outline the problematic areas related to company costs and to contribute to a debate on the method used to determine the amount of fixed and variable costs, their monitoring and follow-up control. This article presents a potential use of regression analysis as an objective tool of economic management in metallurgical companies, as these companies have several specific features [ABSTRACT FROM AUTHOR]

Bacterivorous nematodes are important grazers in the soil micro-food web. Their trophic regulation shapes the composition and ecosystem services of the soil microbiome, but the underlying population dynamics of bacteria and archaea are poorly understood. We followed soil respiration and 221 dominant bacterial and archaeal 16S rRNA gene amplicon sequencing variants (ASVs) in response to top-down control by a common bacterivorous soil nematode, Acrobeloides buetschlii, bottom-up control by maize litter amendment and their combination over 32 days. Maize litter amendment significantly increased soil respiration, while A. buetschlii addition caused an earlier peak in soil respiration. Underlying bacterial and archaeal population dynamics separated into five major response types, differentiating in their temporal abundance maxima and minima. In-depth analysis of these population dynamics identified a broad imprint of A. buetschlii grazing on dominant bacterial (Acidobacteriota, Bacteroidota, Gemmatimonadota, Pseudomonadota) and archaeal (Nitrososphaerota) ASVs. Combined bottom-up control by maize litter and top-down control by A. buetschlii grazing caused a succession of soil microbiota, driven by population changes first in the Bacteroidota, then in the Pseudomonadota and finally in the Acidobacteriota and Nitrososphaerota. Our results are an essential step forward in understanding trophic modulation of soil microbiota and its feedback on soil respiration., (© 2024 The Author(s). Environmental Microbiology published by John Wiley & Sons Ltd.)

The rewetting of formerly drained peatlands can help to counteract climate change through the reduction of CO 2 emissions. However, this can lead to resuming CH 4 emissions due to changes in the microbiome, favoring CH 4 -producing archaea. How plants, hydrology and microbiomes interact as ultimate determinants of CH 4 dynamics is still poorly understood. Using a mesocosm approach, we studied peat microbiomes, below-ground root biomass and CH 4 fluxes with three different water level regimes (stable high, stable low and fluctuating) and four different plant communities (bare peat, Carex rostrata, Juncus inflexus and their mixture) over the course of one growing season. A significant difference in microbiome composition was found between mesocosms with and without plants, while the difference between plant species identity or water regimes was rather weak. A significant difference was also found between the upper and lower peat, with the difference increasing as plants grew. By the end of the growing season, the methanogen relative abundance was higher in the sub-soil layer, as well as in the bare peat and C. rostrata pots, as compared to J. inflexus or mixture pots. This was inversely linked to the larger root area of J. inflexus. The root area also negatively correlated with CH 4 fluxes which positively correlated with the relative abundance of methanogens. Despite the absence or low abundance of methanotrophs in many samples, the integration of methanotroph abundance improved the quality of the correlation with CH 4 fluxes, and methanogens and methanotrophs together determined CH 4 fluxes in a structural equation model. However, water regime showed no significant impact on plant roots and methanogens, and consequently, on CH 4 fluxes. This study showed that plant roots determined the microbiome composition and, in particular, the relative abundance of methanogens and methanotrophs, which, in interaction, drove the CH 4 fluxes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Microgrids are power distribution systems that can operate either in a grid-connected configuration or in an islanded manner, depending on the availability of decentralized power resources, such as sustainable or non-sustainable power sources, battery backup systems, and power demands. The extensive adoption of inverter-based systems poses numerous technological challenges, necessitating a centralized management system to assure the system reliability and monitoring of the energy delivery networks. Thus, this research begins by highlighting these significant obstacles and then analyzes the present-day advances in multilevel control architecture for delivering on promised functionality. This article also discusses the development of innovative control technologies, such as introducing collaborative distributed approaches and reducing conventional three-stage patriarchal administration to fewer stages of system integration and functioning., (© 2023. The Author(s).)

We introduce a data set obtained via a contactless antenna method for detecting partial discharges in XLPE-covered conductors used in medium-voltage overhead power transmission lines. The data set consists of almost three years' worth of data, collected every hour from 9 measuring stations in Czechia and Slovakia. Each sample in the data set represents a single signal gathered for 20 ms. The contactless method is deployed on the same stations as the galvanic contact method, which is used by power distributors and can provide ground truth. Also manually curated data by human expert are present. Successful detection of partial discharges can prevent electricity shutdowns and forest fires resulting from insulation failure due to vegetation contact. The data set is particularly relevant for covered conductors used in mountainous regions where establishing a safe zone is challenging. The contactless method offers advantages such as cheaper and easier installation. The data set has the potential to develop machine learning models to detect partial discharges and facilitate safer and cheaper use of covered conductors., (© 2023. Springer Nature Limited.)

Identification with all humanity measured as an individual characteristic is an important factor related to social and international relations, such as concern for global issues and human rights, prosocial attitudes, intergroup forgiveness, attitudes toward immigrants, solving global problems, reactions to hate crimes and dehumanisation. We examine the factorial structure, psychometric properties and measurement invariance of the Identification with All Humanity (IWAH) scale in student samples from five countries (the United States, Poland, France, Mexico and Chile; N = 1930). Separate confirmatory factor analyses (CFAs) for each country showed a second-order model of one superordinate factor with two subfactors. The cross-country validation of the scale, based on multigroup CFA, confirmed configural and metric invariance between countries for raw scores, and full metric invariance for "pure" scores. This study showed that the IWAH scale can be successfully used for cross-country research and the results from different countries can be compared and integrated., (© 2020 International Union of Psychological Science.)

Nano-sized cerium dioxide (CeO 2 ) particles are emerging as an environmental issue due to their extensive use in automobile industries as fuel additives. Limited information is available on the potential toxicity of CeO 2 nanoparticles (NPs) on terrestrial invertebrates through dietary exposure. In the present study, the toxic effects of CeO 2 NPs on the model soil organism Porcellio scaber were evaluated. Nanotoxicity was assessed by monitoring the lipid peroxidation (LP) level and feeding rate after 14-days exposure to food amended with nano CeO 2 . The exposure concentration of 1000 μg of CeO 2 NPs g -1 dry weight food for 14 days significantly increased both the feeding rate and LP. Thus, this exposure dose is considered the lowest observed effect dose. At higher exposure doses of 2000 and 5000 μg of CeO 2 NPs g -1 dry weight food, NPs significantly decreased the feeding rate and increased the LP level. Comparative studies showed that CeO 2 NPs are more biologically potent than TiO 2 NPs, ZnO NPs, CuO NPs, CoFe 2 O 4 NPs, and Ag NPs based on feeding rate using the same model organism and experimental setup. Based on comparative metal oxide NPs toxicities, the present results contribute to the knowledge related to the ecotoxicological effects of CeO 2 NPs in terrestrial invertebrates exposed through feeding.

Vibration training has become a popular method used in professional sports and recreation. In this study, we examined the effect of whole-body vibration training on the central nervous system and muscle excitability in a group of 28 active men. Subjects were assigned randomly to one of two experimental groups with different variables of vibrations. The chronaximetry method was used to evaluate the effect of a single session of whole-body vibration training on the excitability of the rectus femoris and brachioradialis muscles. The examination of the fusing and flickering frequencies of the light stimulus was performed. An increase in the excitability of the quadriceps femoris muscle due to low intensity vibrations (20 Hz frequency, 2 mm amplitude) was noted, and a return to the initial values was observed 30 min after the application of vibration. High intensity vibrations (60 Hz frequency, 4 mm amplitude) caused elongations of the chronaxy time; however, these differences were not statistically significant. Neither a low intensity vibration amplitude of 2 mm (frequency of 20 Hz) nor a high intensity vibration amplitude of 4 mm (frequency of 60 Hz) caused a change in the excitability of the central nervous system, as revealed by the average frequency of the fusing and flickering of the light stimulus. A single session of high intensity whole-body vibration did not significantly decrease the excitability of the peripheral nervous system while the central nervous system did not seem to be affected.

The study aimed to establish the short-term and long-term effects of whole-body vibration on postural stability. The sample consisted of 28 male subjects randomly allocated to four comparative groups, three of which exercised on a vibration platform with parameters set individually for the groups. The stabilographic signal was recorded before the test commenced, after a single session of whole-body vibration, immediately after the last set of exercises of the 4-week whole-body vibration training, and one week after the training ended. The subjects were exposed to vibrations 3 times a week for 4 weeks. Long-term vibration training significantly shortened the rambling and trembling paths in the frontal plane. The path lengths were significantly reduced in the frontal plane one week after the training end date. Most changes in the values of the center of pressure (COP) path lengths in the sagittal and frontal plane were statistically insignificant. We concluded that long-term vibration training improves the postural stability of young healthy individuals in the frontal plane.

223 lip articles (representing 55 brands) were purchased in 15 European Union Member States and analysed for lead content. Various lip products (lipsticks and lip glosses), shades (red, brown, purple and pink) and price ranges (3 categories) were investigated. The analytical method employed a microwave-assisted acid digestion followed by ICP-MS determination. The results revealed that 49 samples (22%) contained lead at a level higher than 1mg/kg, representing 31% of the tested lipsticks and 4% of the lip glosses. On average, the lead content found in lipsticks (0.75mg/kg) was nearly double that found in lip glosses (0.38mg/kg) and this difference was judged statistically significant at 95% probability. Apart from brown, statistically significant higher levels of lead were also found when comparing the average lead contents in lipsticks and lip glosses of the same shade: pink (0.81 and 0.38mg/kg), purple (0.88 and 0.37mg/kg) and red (0.58 and 0.25mg/kg). The influence of price on lead content was studied on the two lip product types separately. In the case of lip glosses no differences were found. In the case of lipsticks, the more expensive items (price category III) contained a significantly lower quantity of lead in comparison to the cheapest articles (price category I). The lipsticks containing the highest levels of lead belonged to the price category II. In all cases, however, the actual lead concentration measured in the finished products is far below the recommended limits for Germany (20mg/kg) or Canada (10mg/kg). The outcome of this work delivers information about the current situation on the European market and provides information to policy-makers about the quantities of lead in lip articles and technically achievable levels., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The study aimed to establish the short- and long-term effects of vibration on postural stability in young men. A single set of exercises and a 4-week vibration training were assessed for their impact on the center of foot pressure (COP) sway. The sample consisted of 49 male subjects randomly allocated to seven comparative groups, six of which exercised on a vibration platform whose parameters were set individually for the groups. Group VII was the control group. The stabilographic signal was recorded before the test commenced, after a single application of vibration, before the last set of exercises of the 4-week vibration training, immediately afterwards, as well as one week and one month after the training ended. The subjects were exposed to vibration 3 times a week for 4 weeks. Both a single application of vibration and the 4-week vibration training had an effect on all parameter values, but most changes were statistically insignificant. Group III was the only one where the COP sway in the anterior-posterior direction significantly increased after a single exposure to vibration and significantly decreased in both anterior-posterior and medio-lateral planes one week after vibration training compared with the pre-test recordings.

The aim of this study was to evaluate the efficiency of training protocols for whole body vibration (WBV) training through the modulation of the frequency and amplitude of vibration. Despite the large number of studies regarding effects of such training, there is still lack of knowledge regarding optimum training protocols. The study analyzed the influence of whole-body vibration parameters (i.e., the frequency and amplitude) on the myoelectric activity of vastus lateralis and vastus medialis in 29 females with the use of electromyography (EMG). The first and second of the eight consecutive trials were performed without vibrations; the remaining six trials were performed in a randomized order on a platform vibrating at different amplitude (2mm and 4mm) and frequency (20 Hz, 40 Hz and 60 Hz) combinations. The results revealed significantly higher EMG amplitude of both muscles during the vibration as compared with the non- vibrated trials (trial 1 and 2). Furthermore, the EMG activity significantly increased both with the amplitude and frequency, being the highest when the frequency and amplitude of reached 60 Hz and 4 mm, respectively. The study aims to determine the optimal vibration parameters in the aspect of purposeful stimulation of chosen leg muscles. Based on the results of the presented investigation, sports trainers and physiotherapists may be able to optimize training programs involving vibration platforms. Key pointsThe observed vibration effect significantly increases both with the amplitude and frequency.Certain frequency/amplitude combinations of mechanical vibrations cause the same level of myoelectric muscle activity.