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In the ever-evolving landscape of AI, moral educators play a crucial role in promoting the positive development of youth and addressing potential ethical challenges posed by AI. This study employed Q methodology to explore the perceptions of 30 South Korean preservice ethics teachers on AI ethics education, and five distinct perception types emerged: Human-Centered Ethical Guardians of AI, AI Skeptics, AI Abuse Preventers, Competence Cultivators for Coexistence with AI, and AI Social Justice Advocates. These five types encapsulate the distinct gestalt of individuals that intertwines various perceptions regarding AI ethics principles as well as AI technology, the future of the AI era, and the purpose of AI ethics education. By aligning educational approaches with individuals’ perception types, teacher education programs can contribute to a more balanced viewpoint on AI and AI ethics education among preservice teachers. [ABSTRACT FROM AUTHOR] more...

AI technology advancement has sparked a global initiative to educate youth on AI ethics. Understanding students’ prior knowledge is vital. This study explores the diverse perceptions of AI ethics among Korean middle school students using Q methodology. Four types emerged: Privacy Guardians, AI Coexistence Pursuers, AI Ethics Conservatives, and Domestic Distributive Justice Advocates. These classifications reflect the students’ concerns, attitudes toward AI, and value preferences. Despite differences, there is consensus on the importance of human dignity and disagreement with the fair distribution of economic benefits of AI between countries. The findings suggest the need for tailored educational strategies based on students’ perceptions to foster balanced ethical reflection. [ABSTRACT FROM AUTHOR] more...

Background : The purpose of this study was to investigate the association between handgrip strength and prevalence of rheumatoid arthritis and diabetes in older adults. Methods : A total of 4,186 participants 65 years of age and older was included in the study, which utilized data from the fifth Korea National Health and Nutrition Examination Survey. Pearson’s chi-square tests were used to explore the relationship between frequency of participation in physical activity and handgrip strength. The relationships between handgrip strength and prevalence of rheumatoid arthritis and diabetes were determined by logistic regression. Results : Older adults with higher handgrip strength participated more frequently in walking (right hand, 3.71 day/wk; left hand, 3.80 day/wk), strength (right hand, 1.40 day/wk; left hand, 1.43 day/wk), and flexibility exercises (both hands, 2.08 day/wk) than those with lower handgrip strength (right hand, 2.83 day/wk and left hand, 2.81 day/wk for walking; right hand, 0.18 day/wk and left hand, 0.22 day/wk for strength; right hand, 1.17 day/wk and left hand, 1.24 day/wk for flexibility). Higher handgrip strength was associated with reduced prevalence of rheumatoid arthritis (right hand: odds ratio [OR], 0.29; 95% confidence interval [CI], 0.16–0.52; P more...

The flare stack is a piece of equipment, which is used as a safety element at a biogas plant. In the case of a cogeneration unit or gas boiler failure, the biogas is redirected to the flare stack where it is burned. When the flare stack fails, the biogas releases to the atmosphere and an explosive mixture can form. The paper is focused on the description of the causes, which can cause the failure of the equipment. For this purpose, the individual components are described and, subsequently, the possibilities of their failure are discussed. In the next part of the work, the following scenario is considered: failure of the cogeneration unit and flare stack, the subsequent leakage of the biogas to the atmosphere. The calculation for determining the consequences of the biogas leakage is carried out. The size of the gaseous cloud and the explosion pressure in the case of a vapour cloud explosion are determined. The calculations were carried out by the software ALOHA (version 5.4.7). more...

Adolescent girls and young women (AGYW) aged 15 to 24 years face disproportionately high risks of acquiring HIV and other sexually transmitted infections (STIs). A sexual health risk stratification tool can support the development and implementation of tailored HIV and STI prevention services for sub-groups of at-risk AGYW. Data were collected among sexually active AGYW aged 15 to 24 years in Tanzania between April 2015 and March 2017. Exploratory and confirmatory factor analyses were conducted to construct and assess the latent structure of a ten-item scale for rapid assessment of sexual health risks. Items with high factor loadings and minimal cross loadings were retained in the final scale. Scale performance was appraised against condomless sex (defined as unprotected vaginal or anal intercourse) reported by AGYW for construct validity. A three-factor structure of vulnerability to HIV among AGYW was supported with subscales for socioeconomic vulnerability; lack of adult support; and sexual behavioral risks. The chi-square goodness-of-fit test, root mean square error of approximation, comparative fit index, and Tucker-Lewis index indicated a strong goodness-of-fit of the three-factor scale. Cronbach alphas (0.55 for socioeconomic vulnerability, 0.55 for lack of support, and 0.48 for sexual risk) indicated sub-optimal internal consistency for all sub-scales. The factor-item and factor-factor correlations identified in these analyses were consistent with the conceptual framework of vulnerability of HIV infection in AGYW, suggesting good construct validity. The scale also demonstrated a statistically significant association with condomless sex and could be potentially used for sexual health risk stratification (OR = 1.17, 95% CI: 1.12, 1.23). The sexual health and HIV risk stratification scale demonstrated potential in identifying sexually active AGYW at high risk for HIV and other STIs. Ultimately, all AGYW in Tanzania are not at equal risk for HIV and this scale may support directing resources towards those at highest risk of HIV. more...

Background: We investigated the associations between mineral metabolism parameters and mortality to identify optimal targets in Korean hemodialysis patients. Methods: Among hemodialysis patients registered in the end-stage renal disease registry of the Korean Society of Nephrology between March 2012 and June 2017, those with serum calcium, phosphorus, and intact parathyroid hormone (iPTH) measured at enrollment were included. Association of serum levels of calcium, phosphorus, and iPTH with all-cause mortality was analyzed. Results: Among 21,433 enrolled patients, 3,135 (14.6%) died during 24.8 ± 14.5 months of follow-up. After multivariable adjustment, patients in the first quintile of corrected calcium were associated with lower mortality (hazard ratio [HR], 0.84; 95% confidence interval [95% CI], 0.71-0.99; P = 0.003), while those in the fifth quintile were associated with higher mortality (HR, 1.39; 95% CI, 1.20-1.61; P⟨ 0.001) compared with those in the third quintile. For phosphorus, only the lowest quintile was significantly associated with increased mortality (HR, 1.24; 95% CI, 1.08-1.43; P = 0.003). The lowest (HR, 1.18; 95% CI, 1.02-1.36; P = 0.026) and highest quintiles of iPTH (HR, 1.24; 95% CI, 1.05-1.46; P = 0.013) were associated with increased mortality. For target counts achieved according to the Kidney Disease Outcomes Quality Initiative guideline, patients who did not achieve any mineral parameter targets hadhigher mortality than those who achieved all three targets (HR, 1.37; 95% CI, 1.12-1.67; P = 0.003). Conclusion: In Korean hemodialysis patients, high serum calcium, low phosphorus, and high and low iPTH levels were associated with increased all-cause mortality. more...

Abstract Background It has been recognized that alternate day calorie restriction (ADCR) or exercise has positive effects on cardio-metabolic risk factors. It is unclear whether the combined effect of ADCR and exercise (aerobic + resistance training) influences risk. We investigated effects of an 8-week ADCR and exercise program (aerobic + resistance training) on cardio-metabolic risk factors in overweight and obese adults. Methods This study randomized 45 overweight or obese but healthy adults (F = 26, M = 19; aged about 32 to 40 years) into 4 groups: ADCR (n = 13), exercise (n = 10), exercise plus ADCR (n = 12), and control (n = 10) for 8 weeks. Body composition, blood lipids profile, and insulin resistance were measured. The intention to treat (ITT) method was used to analyze all participants that were randomized. Results A total of 35 participants completed the trial (78%). Body weight, body mass index, waist circumference, fat mass and percent body fat were reduced in the exercise plus ADCR group (− 3.3 ± 2.4 kg, p more...

The aim of the paper is an application of the basic principles in determining rental housing prices and factors that may affect them. In the experimental part, an analysis of rental housing in the city of Brno is performed for the 2020 – 2021 period affected by the covid-19 pandemic. The analysis is processed for individual city districts and divided according to apartment layout. Finally, all outputs are compared and the real estate market development is determined with a focus on the biggest changes and their occurrence. more...

In this study, we analyzed social media conversations during the unfolding of the FTX crisis, the biggest cryptocurrency scandal in United States history. Drawing on the accessibility‐diagnosticity framework, we examined the negative spillover effect of the crisis using a natural language processing approach. We specifically assessed whether there was a negative spillover from FTX to other crypto entities with different levels of diagnostic attribute similarity. We collected a large corpus of Twitter conversations related to the FTX collapse in 2022 and used the association rule analysis to determine the association between FTX and other crypto entities. Our analysis revealed that the number of tweets mentioning FTX and other crypto entities changed in line with a series of real‐world events during the FTX crisis. The negative spillover of the FTX crisis occurred primarily during the first 10 days as the FTX scandal unfolded. The results indicated that the FTX crisis spilled over to highly accessible and diagnostic crypto entities, such as Binance, Bitcoin, and the cryptocurrency industry in general. On the other hand, less accessible and less diagnostic crypto entities/currencies like Ethereum and Coinbase did not experience negative spillover from the scandal. [ABSTRACT FROM AUTHOR] more...

The paper presents the results of a conceptual study of lightweight wooden construction hall building with polygonal ground plan, suitable for agriculture. It comprises evaluation of chosen technical and functional characteristics and possibilities for animal production. The results of the study confirm advantages (mainly lower material and costs demandingness, environmentally friendliness, light-weight construction, fast assembly operations) and disadvantages (mainly larger range of groundwork, higher demandingness on roof structure, foundation of slab constructions and anchoring of vertical bearing constructions). Values of radial tensile stress at an interval of 9.0 to 21.0 MPa and tangential tensile stress at an interval of 1.4 to 16.0 MPa were calculated on vertical load 100 kN at the top of the construction). The construction makes possible to achieve a span as far as 60 m with effective canvas strain at large radius curvature from 80 m to 100 m. more...

Pc1 pulsations are geomagnetic fluctuations in the frequency range of 0.2 to 5 Hz. There have been several observations of Pc1 pulsations in low earth orbit by MAGSAT, DE-2, Viking, Freja, CHAMP, and SWARM satellites. However, there has been a clear limitation in resolving the spatial and temporal variations of the pulsation by using a single-point observation by a single satellite. To overcome such limitations of previous observations, a new space mission was recently initiated, using the concept of multi-satellites, named the Small scale magNetospheric and Ionospheric Plasma Experiments (SNIPE). The SNIPE mission consists of four nanosatellites (~10 kg), which will be launched into a polar orbit at an altitude of 600 km (TBD) in 2020. Four satellites will be deployed in orbit, and the distances between each satellite will be controlled from 10 to 1,000 km by a high-end formation-flying algorithm. One of the possible science targets of the SNIPE mission is observing electromagnetic ion cyclotron (EMIC) waves. In this paper, we report on examples of observations, showing the limitations of previous EMIC observations in low earth orbit, and suggest possibilities to overcome those limitations through a new mission. more...

A lunar vehicle radiation dosimeter (LVRAD) has been proposed for studying the radiation environment on the lunar surface and evaluating its impact on human health. The LVRAD payload comprises four systems: a particle dosimeter and spectrometer (PDS), a tissue-equivalent dosimeter, a fast neutron spectrometer, and an epithermal neutron spectrometer. A silicon photodiode sensor with compact readout electronics was proposed for the PDS. The PDS system aims to measure protons with 10–100 MeV of energy and assess dose in the lunar space environment. The manufactured silicon photodiode sensor has an effective area of 20 mm × 20 mm and thickness of 650 μm; the electronics consist of an amplifier, analog pulse processor, and a 12-bit analog-to-digital converter for signal readout. We studied the responses of silicon sensors which were manufactured with self-made electronics to gamma rays with a wide range of energies and proton beams. more...

An evaluation of transforming growth factor beta (TGFβ), hepatocyte growth factor (HGF), basic fibroblast growth factor (FGF-2), fibroblast growth factors receptor 1 (FGFR1) and Hox-positive cells in the human placenta, and their correlation with gestational time at delivery and pregnancy outcomes, may provide not only a better understanding of the role of Hox genes and growth factors in human development, but also may be of clinical importance in reproductive medicine. This study analyzed the immunohistochemical identification of TGFβ, HGF, FGF-2, FGFR1 and HoxB3 in placentas of various gestational ages. We found few (+) TGFβ, moderate (++) FGF-2 and numerous (+++) HGF and FGFR1 positive structures. Occasional (0/+) to numerous (+++) HoxB3-positive structures were detected in different types of placental cells specifically, cytotrophoblasts, syncytiotrophoblast, extravillous trophoblasts, and Höfbauer cells. Correlating the appearance of HoxB3 staining in placentas with neonatal parameters, we found a statistically significant negative correlation with ponderal index (r = −0.323, p = 0.018) and positive correlation with neonate body length (r = 0.541, p = 0.046). The number of HoxB3-positive cells did not correlate with growth factors and gestational age, but with neonatal anthropometrical parameters, indicating the role of HoxB3 not only in placental development, but also in the longitudinal growth of the fetus. TGFβ and FGF-2 did not play a significant role in the development of the placenta beyond 22nd week of pregnancy, while HGF and FGFR1 immunoreactive cells increased with advancing gestation, indicating increasingly evolving maturation (growth, proliferation) of the placenta, especially in the third trimester. more...

The chemical modification of electrode surfaces has attracted significant attention for lowering the limit of detection or for improving the recognition of biomolecules; however, the chemical processes are complex, dangerous, and difficult to control. Therefore, instead of the chemical process, we physically modified the surface of carbon-nanotube/polydimethylsiloxane composite electrodes by dip coating them with functionalized multi-walled carbon nanotubes (F-MWCNTs). These electrodes are used as working electrodes in electrochemistry, where they act as a recognition layer for sequence-specific DNA sensing through π–π interactions. The F-MWCNT-modified electrodes showed a limit of detection of 19.9 fM, which was 1250 times lower than that of pristine carbon/polydimethylsiloxane electrodes in a previous study, with a broad linear range of 1–1000 pM. The physically modified electrode was very stable during the electrode regeneration process after DNA detection. Our method paves the way for utilizing physical modification to significantly lower the limit of detection of a biosensor system as an alternative to chemical processes. more...

Abstract The atomic, electronic, and magnetic properties of vacancy structures with triangular shape related to their growth in single hexagonal boron nitride (h-BN) sheet are investigated using density functional theory calculations. We find that the optimized structures of triangular vacancies depend on the vacancy sizes with N-terminated zigzag edge. Then, vacancy structures obtained during the vacancy evolution in h-BN sheet are considered by removing a boron-nitrogen pair (BN pair) from edges of triangular vacancies. The magnetic properties of those vacancy structures are investigated by local density of states and spin densities. It is found that the stability of the optimized structures with a BN missing pair depends on the BN-pair missing position: the most stable structure is a BN-pair missing structure at the edge face region with the smallest magnetic moment. more...

The paper compares the methods of hygienisation of wastewater treatment plants sludges with respect to meet legislative requirements of conditions for using the treated sludge on agricultural land. The paper draws a comparison of the experimental results between the method of hygienisation and stabilisation of the sludge through the autothermic aerobic thermophilic stabilisation (AATS) by pure oxygen and the method of sludge hygienisation by pasteurization. Results of the experiment confirm that sewage sludge treated by both assessed hygienisation technologies meets legislation requirements for application to agricultural soil. more...

In this study, the combustion of olive byproducts was investigated using the TG-FTIR technique. Different types of olive biomass were considered: twigs, leaves, olive-mill waste from the two-phase decanting method, and wastewater from the three-phase system. The reaction regions, ignition, and burnout temperatures at different heating rates were determined using TG/DTG analysis and the thermogravimetry results. Comprehensive combustion, ignition, burnout, and flammability indexes were also calculated. The highest combustion index values were obtained for waste from the three-phase system, followed by the two-phase decanting method, then with leaves and small twigs. The order of the index values indicated that the sample from the three-phase process ignited more quickly and yielded faster. The changes in activation energy calculated using different model-free isoconversional methods—Friedman, Ozawa–Flynn–Wall, and Kissinger–Akahira–Sunose—fell within the range of 130–140 kJ/kmol. FTIR analyses presented differences in the exhaust gas composition for specific combustion temperature ranges. more...

The purpose of this meta-analysis was to investigate the influence of cardiorespiratory fitness (CF) levels on dementia risk and dementia mortality. MEDLINE and EMBASE databases were used to search for eligible studies from January 1990 to September 2019. To be included, the study was required to be a prospective cohort study that provided CF measurements and indicated relative risk and confidence intervals for the associations between CF and dementia risk and mortality. A total of six studies were selected for this meta-analysis. Low-level CF was associated with nearly three times greater risk of dementia (2.93, 95% confidence interval [1.31, 6.57]; p <.05) compared with a high-level CF. Enhanced CF levels decreased the risk of dementia, and an increase of one metabolic equivalent of task in the CF level reduced the risk of dementia and dementia mortality. Maintaining more than 12 metabolic equivalents of task of CF level was required to substantially decrease dementia risk and dementia mortality. [ABSTRACT FROM AUTHOR] more...