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The paper presents the results of dimensional and shape analysis of additively manufactured shaped parts of foundry moulds; specifically, shaped gate valve inserts made of DIEVAR steel used in the die-casting process of aluminium alloys. The paper aims to provide a comprehensive overview of dimensional and shape analysis during the manufacturing of shaped mould parts before their use in foundry operating conditions. The manufacturing operations include additive manufacturing, heat treatment, machining, and applying a protective coating. Based on these technological operations, the required component accuracy is achieved before application in the operating conditions. The dimensional and shape analysis was measured by 3D scanning and 3D measuring methodology on a coordinate measuring machine. The ROMER ABSOLUTE ARM 3D scanning arm and the THOME PRÄZISION coordinate measuring machine were used for the measurements. The paper presents findings in the development and application of additive manufacturing technologies in engineering metallurgy.

The year 2018 was distinguished by a warm summer with extended periods of low or no precipitation. In this context, we investigated the intra-annual dynamics of xylem differentiation phases and quantitative vessel anatomy to analyse the age effect on the xylem formation response of younger (50 years) and older (135 years) mature European beech trees under summer drought conditions. The xylem formation dynamics of young and old trees were performed on microcores collected at weekly intervals in the Rájec-Němčice ecological station in the South Moravia region (Czech Republic). The onset of xylem formation was found identical in both age trees, and most of the trees ceased their enlargement by the end of July, which is attributed to the harsh environmental conditions of this month. Young trees were characterised by a 10-day extended enlargement period and a higher growth rate, resulting in more vessels and a wider tree-ring width. No significant linkage was found between intra-annual environmental conditions of the 2018 year or age effect and the vessel anatomy traits.

Abstract As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels.

Abstract The article focuses on the issue of improving the efficiency of a Foundry Degassing Unit (FDU) via operational testing of aluminium alloys during casting at MOTOR JIKOV Slévárna a.s.. As part of the research, the efficiency of the refining process in the FDU was assessed. The main emphasis was placed on determining the moment of the greatest decrease in the hydrogen content in the melt and whether it is possible to shorten the refining cycle. The values of the Dichte Index were determined, on the basis of which the degassing curve was plotted and the progress of the melt degassing was assessed. To ensure the required quality of castings, the maximum allowable value of the Dichte Index ranged from 3 to 4%. During the process, the temperature drop during the refining cycle was also determined. The total temperature drop from pouring the melt into the ladle to the end of refining ranged from 26 to 32 °C, which is within the acceptable limits of the foundry. Based on the knowledge resulting from the operational experiments, recommendations were formulated to optimize the refining technology at the FDU for the MOTOR JIKOV Slévárna a.s. foundry.

This contribution describes the application of HPGe detector for the airborne quantitative analysis. The hardware of the airborne HPGe system was designed from the commercial components with only exception of the newly designed AirHPGeSpec special software to control, measure and process the data. The system was calibrated for the local air kerma rates measured on helicopter board and its conversion to the air kerma rates at 1 m above the ground was proposed. Two examples of the air kerma rates measured over the former uranium mining areas are presented and compared with the results of other airborne system on the board. This airborne HPGe system could be also used for measuring the surface activities in a radiation event. The nuclides of 131I, 132Te -132I, 133I, 134I, 135I, 137Cs, 134Cs, 88Rb and 103Ru were selected from possible nuclear power plant emergency scenarios. The Monte Carlo simulation was used to calculate HPGe detector efficiencies for the flight altitudes from 25 to 300 m for the energies from 300 keV to 3 MeV of the nuclides in question. Also, the detection limits according to the Currie method as well as ISO 11929-2010 for selected nuclides are presented.

Abstract Physical modelling is successfully used to understand mechanisms involved in the aluminium refining process by injecting inert gas into the liquid metal through rotors. Two types of industrial impellers, which are extremely different in construction, were tested in the research. The aim of the research was to determine the effectiveness of their operation depending on their degree of wear. This type of research has not been tested on water models so far. During the process, the parameters were changed, such as the gas flow rate from 13 to 19 L/min, the rotor speed from 325 to 400 rpm and the height of the rotor from the bottom of the refining reactor. Tests were carried out for new and worn rotors. Oxygen removal rate curves were prepared on the basis of tests determining changes in oxygen content in the model liquid as a function of time for changing rotor speed values. It was found that the efficiency of hydrogen removal from the model liquid was higher when worn impellers were used in the model. In order to verify results of model tests, a metallographic analysis of samples obtained in industrial conditions and using the analysed process parameters was carried out.

Silver fir (Abies alba L.) wood samples were charred on one surface using an enhanced version of the traditional Japanese Yakisugi method. The 15 charred boards obtained from five charring chimneys were divided into three different zones and investigated for their physical properties. The density profile, water absorption after 24 h of water submersion, and Brinell hardness were analyzed. In general, the temperature-time regime, which causes inside surface carbonization, was more evident at the bottom than at the top of the chimney. The density profile of the specimens revealed that the surface charring treatment decreased the surface density of the wood significantly. A gradient was visible from 383 kg/m² at the bottom to 424 kg/m² at the top. Water absorption measurements showed that a thicker carbonized layer could take up more water as a result of increased porosity. While 3,684 g/m² were absorbed at the bottom, the top accounted for only 2,533 g/m². Furthermore, with increasing thickness of the charred layer, the hardness gradually decreased. The average of the charred specimens reached only 3.2% of the hardness of the uncharred back side of the specimens.

Using 3D scanning, coordinate measuring machine, and roughness measurements we evaluated and compared zinc alloy castings produced in conventionally and additively manufactured shaped mould parts. Tests were conducted on castings from new shaped parts and subsequently after approximately every 100,000 shots. Castings from conventional parts had higher dimensional stability, but both types showed decreasing dimensional deviations over time. Castings from new additively manufactured parts had higher roughness initially, but this improved with use. Overall, there were no significant issues, and the benefits of additive-shaped parts prevailed. However, more testing is needed for a final recommendation for use in real operating conditions, requiring hundreds of thousands more shots.

The present paper describes a comparison of the efficiency of different types of rotors used in the refining of aluminium melt at a foundry degassing unit (FDU). Physical modelling was used to obtain data for six different rotor types under defined experimental conditions. In order to evaluate the data from the physical model, an evaluation method based on the interpolation of degassing curves was developed in such a way that the resulting characteristic can be expressed by a single parameter. Using the new methodology, the datasets were replaced by a single dimensionless parameter, a, which characterizes the rotor performance at a given gas flow rate. Based on the comparison of these performance parameters, it was possible to mutually compare the rotor efficiency depending on the selected conditions. The comparison is also demonstrated on the expected degassing time to a certain required concentration. Based on the physical model results, the study found that rotor D had the highest degassing efficiency, followed by rotors F and A. Rotors B and E had similar efficiency at a flow rate of 17 Nl·min−1. However, rotor B showed better efficiency at higher inert gas flow rates (19 and 21 Nl·min−1), while rotor E showed better efficiency at lower flow rates (13 and 15 Nl·min−1).

The article deals with the use of computed tomography, an advanced method for evaluating the quality of aluminium castings. Casting quality is a key factor in ensuring safety and reliability in industrial applications. Computed tomography is a comprehensive method allowing a three-dimensional, high-resolution view of the internal structure of materials. The main focus of this paper is the study of BRACKET REAR aluminium castings, manufactured in two-piece moulds using a high-pressure die-casting technology. In this paper, four castings have been analysed which are produced in one cycle. The focus is on the problem of porosity and open stagnation in the castings. A numerical simulation has also been used to illustrate the occurrence of porosity, which can be used to determine both the occurrence of porosity and the occurrence of unfilled volume. The experimental part of the paper describes the methods used to evaluate the BRACKET REAR castings. The numerical simulation was performed in ProCAST 18.0 to determine the occurrence of porosity in the castings under study. The evaluation of computed tomography was performed in myVGL 3.0 2023 software to analyse the internal defects in the castings. The evaluation focused on assessing internal defects and their subsequent effect on the functionality of the final casting.

Foundry Degassing Units (FDU) are used for refining aluminum alloys. For an ideal refining process using an FDU unit, it is necessary to select several parameters, which are linked to each other. For a rotary impeller, we searched for several parameters, such as its optimal shape, speed in the liquid alloy, and distance from the bottom of the refining ladle, where the aforementioned parameters contribute to the overall wear and life of the rotor and, consequently, of the rotor shaft. The Computational Fluid Dynamics (CFD) method can be used to determine the above-mentioned parameters. This paper describes the particular steps of preparation of rotor geometry for the subsequent setting up of the basic numerical model.

Neuropsychiatric symptoms are common in Parkinson's disease (PD). We investigated the relationship between neuropsychiatric symptoms and current and future diagnosis of PD dementia (PDD). Individuals with PD who had a study partner were enrolled (n = 696). Study partners were administered the Neuropsychiatric Inventory or Neuropsychiatric Inventory Questionnaire at baseline. Participants were assigned a cognitive diagnosis at baseline and follow up visits. Hallucinations were significantly associated with a diagnosis of PDD cross-sectionally (p

Forest dynamics are monitored at large scales with remote sensing, but individual tree data are necessary for ground-truthing and mechanistic insights. This study on high temporal resolution dendrometer data across Europe reveals that the 2018 heatwave affected tree physiology and growth in unexpected way.

Social media (SM) is now a popular place for content creation and a means of communication between young adults. Their increasing participation in our lives means that they replace us face to face contacts (FTF), which can affect our mental health. The above changes in communication habits may correlate with the occurrence of depressive states and a sense of social isolation. The aim of the study is to analyze the relationship between the use of MS and the occurrence of depressive states in young adults on the basis of selected literature. The topic of emotional support and a sense of social isolation will also be discussed. PubMed and Google Scholar databases were used to select the appropriate literature, and only research was used. The cited studies on the use of MS and depression showed that people who spent the most time on social media showed an increased risk of experiencing a depressed mood. Another study analyzed the likelihood of depression depending on the method of emotional support. The comparison of emotional support in FTF (face to face) communication with the support obtained through MS showed that the possibility of depressive symptoms was lower for FTF communication and higher for the second method, respectively. The use of social media among young adults contributes to an increased risk of depression, perceived social isolation and reduced emotional support. Moreover, it has been proven that addiction to MS positively correlates with the presence of depressive symptoms.

Alcohol consumption has many negative effects on the human body, and has been proven to have teratogenic effects on fetal development. Prenatal alcohol exposure (PAE) is associated with growth deficits and neurodevelopmental disorders, including fetal alcohol spectrum disorder (FASD). Despite such effects, there are still many women who do not give up the consumption of alcoholic beverages during pregnancy. This article, based on a review of available studies on PubMed, examines whether prenatal alcohol exposure can cause problems in children's speech development and promote communication problems in children, as well as in adolescents. Longitudinal observations on prenatal alcohol exposure (PAE) have shown that children up to the age of 3 after PAE have difficulties in receptive or expressive communication compared to a group not prenatally exposed to alcohol. Alcohol has been shown to be the overriding factor causing disorders in the development of the brain and nervous system, which are the main structures responsible for the process of speech development and also the formation of communication skills. Studies among adolescents with PAE have shown that they have weaker spoken and written language skills than those without PAE or with low PAE. This also translates into difficulties in developing their communication skills, which can make it much more difficult for them to become independent and move smoothly through the difficult period of adolescence.

Introduction : Endometriosis is a disease that currently affects 10-15% of women of reproductive age worldwide. The main problem of female patients, in addition to infertility, is pain, which varies greatly, significantly reduces the quality of life and affects family, social, sexual and professional life. Pharmacological treatment, which is applied both after the excision of the lesions and in patients who were not eligible for surgery, is an important element of pain therapy. There are also other methods, such as appropriate diet change, supplementation, acupuncture, electrotherapy, which are partially effective. Method : review of the recent literature based on PubMEd ,Google scholar research based on the following keywords : endometriosis treatment, hormonal treatment of endometriosis, quality of life of patients with endometriosis Purpose of work : Comparison of the mode of action and effectiveness of individual non-surgical methods of treating pain in patients with endometriosis.

The objective of this research was to develop a mathematical model of the hot-pressing process for making flat-pressed wood–polymer composites (FPWPCs). This model was used to calculate and predict the temperature and time required for FPWPC pressing. The model's performance was analysed using the experimental results of hot pressing FPWPCs. It was found that an increase in the content of wood particles led to a rapid increase in the pressing time. The model and experiment showed that the core temperature of the wood–polymer mat remained nearly constant for the first 20–30 s of the hot-pressing process. After this period, this temperature increased rapidly until it reached 100 °C, after which the rate of increase began to decelerate sharply. This transition was more distinct in FPWPCs with a high wood-particle content, while in those with a high thermoplastic-polymer content, it was smoother. Increasing the pressing temperature contributed to a reduction in the time required to heat the FPWPC, as confirmed by both experimental data and the modelling of the hot-pressing process. A decrease in the predicted density of the FPWPC resulted in a directly proportional increase in the time required to heat the mat. Validation of the mathematical model revealed a mean absolute percentage error (MAPE) of only 2.5%, confirming its high precision and reliability. The developed mathematical model exhibited a high degree of accuracy and can be used for further calculations of the time required for FPWPC pressing, considering variable parameters such as pressing temperature, wood–polymer ratio, mat thickness, and density. [ABSTRACT FROM AUTHOR]

The year 2018 was distinguished by a warm summer with extended periods of low or no precipitation. In this context, we investigated the intra-annual dynamics of xylem differentiation phases and quantitative vessel anatomy to analyse the age effect on the xylem formation response of younger (50 years) and older (135 years) mature European beech trees under summer drought conditions. The xylem formation dynamics of young and old trees were performed on microcores collected at weekly intervals in the Rájec-Němčice ecological station in the South Moravia region (Czech Republic). The onset of xylem formation was found identical in both age trees, and most of the trees ceased their enlargement by the end of July, which is attributed to the harsh environmental conditions of this month. Young trees were characterised by a 10-day extended enlargement period and a higher growth rate, resulting in more vessels and a wider tree-ring width. No significant linkage was found between intra-annual environmental conditions of the 2018 year or age effect and the vessel anatomy traits. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the differences in golf swing execution in terms of the parameters of the pelvis and thorax movement between the sexes in junior golfers and their relation to the golf club velocity. Elite female and male players (age: 15.4 ± 1.0 and 15.8 ± 1.7 years, respectively) performed 10 golf swings with a driver under laboratory conditions. Pelvis and thorax movement parameters and golf club velocities were measured using a three-dimensional motion capture system. Statistical parametric mapping analysis of pelvis–thorax coupling revealed a significant difference (p < 0.05) between boys and girls during backswing. Analysis of variance showed a significant effect of sex on the parameters of maximal pelvic rotation (F = 6.28, p = 0.02), X-factor (F = 5.41, p = 0.03), and golf club velocity (F = 31.98, p < 0.01). No significant relationship was found between pelvis and thorax movement parameters and golf club velocity in the girls. We found a significant negative relationship between the parameters of maximal thorax rotation and golf club velocity (r = −0.941, p < 0.01) and between X-Factor and golf club velocity (r = −0.847, p < 0.05) in the boys. We suggest that these negative relationships in males were caused by the influence of hormones during their maturation and biological development, where there is decreased flexibility (lower shoulders rotation and X-factor) and growth of muscle strength (higher club head velocity).