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Globular clusters of the Gaia Enceladus/Sausage I. Orbital and dynamical evolution on cosmological timescales

Maryna Ishchenko Mykyta Bilodid Peter Berczik

Publication Name: Astronomy and Astrophysics

Publication Date: 2025-12-01

Volume: 704

Issue: Unknown

Page Range: Unknown

Description:

Context. The history of our Galaxy is shaped by significant merger events, which contribute to its mass and to the distribution of stars, but which also bring globular clusters that act as the main tracers of the accretion history of the Milky Way. Aims. We investigated Gaia-Enceladus/Sausage globular cluster samples and studied their orbital and dynamical evolution over cosmological timescales in external time-variable potential. We estimated the limits of distribution of the escaped stars from the globular clusters’ orbital evolution in energy angular momentum space. Methods. To reconstruct the orbital evolution of the known globular clusters of the dwarf galaxy Gaia-Enceladus/Sausage, we used the parallel N-body code φ-GPU. We investigated the relationship between globular clusters and their progenitor by analysing their orbital parameters and phase-space distribution during 9 Gyr of evolution in the past. We created a N-body model of Gaia-Enceladus/Sausage globular clusters and analysed their dynamical evolution and distribution of the escaped stars today. Results. We summarised the samples of the Gaia-Enceladus/Sausage globular clusters and created two main categories: ‘most probable’ and ‘tentative’, with 15 and 9 clusters, respectively. We analysed the evolution of their kinematic, orbital, and phase-space parameters in the external time-variable potential. We defined phase-space distribution limits of stars that escape from globular clusters during 9 Gyr of evolution: a specific energy from −18 to −12.2 ×104 km2 s−2, Lz from −0.98 to 0.72 ×103 kpc km s−1, and Lperp from 0 to 1.8 ×103 kpc km s−1. The limits of the GE/S debris in Galactic area based on orbital parameters of the GC’s escaped stars are: for apocentre and pericetre distances of 10–28 and 1–4 kpc, <18 kpc in Galactocentric radius and <|15| kpc in the Z direction. Generally we compared the phase-space distribution of escaped stars from the GCs GE/S debris energy-angular momentum limits with the observed very metal-poor stars, which belong to the GE/S itself and produce consistent results.

Open Access: Yes

DOI: 10.1051/0004-6361/202557210

Examining the relationship between physical activity and sleep among university students

Róbert Járai Feifei Wang Nikoletta Barka Róbert Járai Szilvia Boros

Publication Name: Frontiers in Sports and Active Living

Publication Date: 2025-01-01

Volume: 7

Issue: Unknown

Page Range: Unknown

Description:

Objective: Physical activity and adequate sleep are essential for health and wellbeing. University students face distinct challenges affecting their habits. This study investigates sociodemographic impacts on physical activity and sleep patterns, and examines the association between physical activity and sleep quality in Hungarian university students. Methods: An online cross-sectional survey was conducted among students (N = 1,340, mean age 20.00 ± 1.59 years; 60.7% female and 39.3% male) from the Budapest University of Economics and Business. The survey was based on sociodemographic data, the Hunarian version of the International Physical Activity Questionnaire-Short Form (IPAQ-SF), and the Pittsburgh Sleep Quality Index (PSQI) questionnaires. In IPAQ-SF, respondents indicated physical activities lasting at least 10 min during the last seven days. Responses were categorised by WHO and IPAQ guidelines. Metabolic Equivalent of Task (MET) was calculated. Statistical analyses were conducted using IBM SPSS Statistics 29.0.0.0, with significance set at p < 0.05. Results: Most participants (85.8%–86.9%) performed below the WHO recommendations for moderate-intensity physical activity. Significant sex differences were noted in physical activity levels (p < 0.001 for vigorous intensity; p < 0.043 for moderate intensity), with men being more active than women. Regarding sleep quality, 57.1% of participants reported good sleep quality (PSQI 0–5), 36.1% had moderate sleep disturbances (PSQI 6–10), and 6.8% experienced poor to severe sleep disturbances (PSQI 11–21). Women reported significantly poorer sleep quality than men did (p < 0.001). Multiple linear regression analysis revealed a significant interaction between energy expenditure on physical activity and sports participation frequency (β = −0.09, p = 0.012), indicating that regular sports participation may buffer against potential negative effects of high overall physical activity on sleep quality. The model explained 3.1% of the variance in sleep quality (R2 = 0.031, p < 0.001). Conclusion: The relationship between physical activity (MET-minutes/week) and sleep quality was moderated by the frequency of sports participation. Given that poor sleep can negatively impact academic performance, health, and well-being, these findings support the promotion of organized sports within university settings. Interventions targeting both physical activity and sleep hygiene may yield synergistic benefits, particularly for students with sedentary lifestyles.

Open Access: Yes

DOI: 10.3389/fspor.2025.1640770

Discrete Bacterial Memetic Evolutionary Algorithms for Solving High Complexity Problems: PLENARY TALK

László T. Kóczy

Publication Name: Saci 2022 IEEE 16th International Symposium on Applied Computational Intelligence and Informatics Proceedings

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 13-14

Description:

In the talk, several examples will be presented with standard benchmarks going up to large numbers of graph nodes, and the DBMEA results will be compared with the best practices from the literature. The predictability feature will also be illustrated by size-running time graphs. Reference will be made to the importance of determining the initial population in achieving fast and accurate results. A new approach, the Bounded Radius Heuristics will be presented. In the last part of the talk, a series of fuzzy extensions of the Time Dependent TSP (TD TSP) will be introduced, an extension of the TSP with real life aspects where the natural fluctuation of the traffic in certain areas causes non-deterministic features causing additional difficulties in the quasi-optimization. The novel extensions will be also tackled with the DBMEA approach successfully. As a conclusion, one more example will be mentioned where the discrete NP-hard problem is of a rther different nature, and it will be shown that by changing the local search technique appropriately, DBMEA can still deliver superior results.

Open Access: Yes

DOI: 10.1109/SACI55618.2022.9919503

On the Python programming language for statisticians

Attila Sóti

Publication Name: Statisztikai Szemle

Publication Date: 2020-01-01

Volume: 98

Issue: 4

Page Range: 324-352

Description:

This study provides easily accessible introduction to the Python programming language for readers who are beginners in software development but proficient in statistics. The tutorial presents the beauty of Python programming, outlines a path to an easily executable code and also highlights pitfalls of Python. Most of the statistical methods used as an example are deliberately basic, with the exception of cluster analysis. As a final step, the importance of data visualization is highlighted and examples of the possible use of Python in this area are given

Open Access: Yes

DOI: 10.20311/stat2020.4.hu0324

Evaluation of Good Manufacturing Practices (GMP) in Aceh patchouli industry

Irfan Zikri Friesca Erwan Zaudhatul Ulya Fitri Deliana Muhammad Auza

Publication Name: Iop Conference Series Earth and Environmental Science

Publication Date: 2025-01-01

Volume: 1510

Issue: 1

Page Range: Unknown

Description:

Good Manufacturing Practices (GMP) in community-based and smallholder patchouli oil production represents a positive initiative to enhance productivity and profitability while mitigating risks associated with workforces, workflows, and environment. This study aims to explore the implementation of GMP in a patchouli industry center run by community-based cooperative in Lhoong, Aceh Besar. This is a qualitative study which collect data from interviews and observations, and analyzes the data using comparative analysis. Data is classified according to the 5P indicators of GMP, which consists of products, people, processes, procedures, and premises. This study reveals that while GMP is generally unfamiliar to those in community-based and smallholder patchouli oil production, it's practices are already implemented in the knowledge of farmers and producers. However, there is a need for the community and smallholders to enhance their understanding and awareness of GMP, and actively participate in the training provided by stakeholders. The implementation of GMP promotes green technology initiatives to strengthen the sustainability of patchouli oil industry while fostering economic growth and improving community well-being. This study recommends the formation of a task force team within the community, trained to implement GMP perfectly in the patchouli oil industry center. Additionally, the findings of this study contribute to the goals of SDG 9 (Industry, Innovation, and Infrastructure) and SDG 12 (Responsible Consumption and Production).

Open Access: Yes

DOI: 10.1088/1755-1315/1510/1/012078

Overview and comparative results of speech-based excitation signals for virtual localization and real-life applications

György Wersényi

Publication Name: 20th International Congress on Acoustics 2010 Ica 2010 Incorporating Proceedings of the 2010 Annual Conference of the Australian Acoustical Society

Publication Date: 2010-12-01

Volume: 5

Issue: Unknown

Page Range: 3885-3889

Description:

In virtual audio synthesis we use different excitation signals for listening tests. These tests are executed using headphone playback and real-time HRTF synthesis. Besides noise signals, speech is often used for tests especially for real life applications, such as mobile phones, various voice transmission lines, computer environments or accessories for the visually impaired, where speech intelligibility is important. This paper presents a summary of results of a listening test using different signals including speech in a virtual audio environment aimed at blind persons. Results show how speech contributes to the accessibility to computers and performs in a comparative test for virtual audio simulation. Furthermore, additional speech test signals are overviewed and introduced, such as speech-chorus signals, segmented spondees and the newly developed spearcons.

Open Access: Yes

DOI: DOI not available

Trematurid mites (Mesostigmata: Uropodina) associated with bark beetles (Coleoptera: Scolytinae) in Mexico

Jenő Kontschán Edith Guadalupe Estrada-Venegas Stacy R. Blomquist Alejandro Rodríguez-Ortega John C. Moser Martha Patricia Chaires-Grijalva Armando Equihua-Martínez Víctor Javier Arriola-Padilla Mauricio Pérez-Silva

Publication Name: Acarologia

Publication Date: 2026-01-01

Volume: 66

Issue: 2

Page Range: 364-376

Description:

Phoretic mites associated with bark beetles (Curculionidae: Scolytinae) play crucial roles in forest ecosystems, yet their diversity and distribution in Mexico remain understudied. This study aims to identify the species of the family Trematuridae (genera Trichouropoda and Oodinychus) associated with bark beetles across major coniferous forests in Mexico and to describe their host specificity and attachment patterns. A total of 1,713 bark beetles belonging to nine species were examined from 24 Mexican states. Mites were collected from the host bodies, galleries, and collection vial sediments. Eleven trematurid species were identified. Mites were recorded in ten states, with Trichouropoda polytricha being the most widespread and generalist species, associated with seven host species. A significant disparity in mite prevalence was observed among hosts, ranging from 1.57% in Dendroctonus mexicanus to 25.58% in D. rhizophagus. Phoretic deutonymphs exhibited a clear preference for specific attachment sites, primarily the ventral surface (29%) and gular area (22%). Furthermore, the presence of mites in both new and old galleries confirms these structures as essential micro-ecosystems for their biological cycle. Our findings highlight a high degree of host plasticity in certain species and a complex symbiotic relationship within the gallery environment. This research provides a fundamental baseline for future studies on the ecological impact of mite-beetle associations in Mexican forest health.

Open Access: Yes

DOI: 10.24349/qznl-uogs

Steel Exoskeletons for the Seismic Retrofit of an Existing RC Building: Optimal Design and Life Cycle Assessment

Marco Domaneschi Roberta Di Bari Majid Movahedi Rad Raffaele Cucuzza Giuseppe Carlo Marano Jana Olivo Giuseppe Andrea Ferro

Publication Name: Lecture Notes in Civil Engineering

Publication Date: 2025-01-01

Volume: 770 LNCE

Issue: Unknown

Page Range: 214-225

Description:

The growing need for structural, energetic and architectonic refurbishment of the existing structures led to the emergence of alternative retrofitting techniques. Among them, steel exoskeletons stand out for their non-invasive and time-efficient nature, especially in cases where the relocation of the building’s activities is not allowed. In this research, the optimal exoskeleton configuration, in terms of number of exoskeletons and their position around the building, along with the sizing of their constituent elements, has been obtained through an optimization process. The optimization tool is based on a Genetic Algorithm with the aim of weight minimization, including as constraints a maximum allowable inter-storey drift for preserving the elastic behavior of the existing building, and the structural safety of the exoskeleton members. Two exoskeleton typologies were selected as case studies, employed for the retrofitting of an existing RC moment-resisting frame building. Furthermore, Life Cycle Assessment analyses were conducted on the optimal configurations considering two materials: steels with high and low percentages of recycled materials. The results yielded interesting insights into the structural performance of both exoskeleton typologies, as well as into the environmental characteristics of both studied materials.

Open Access: Yes

DOI: 10.1007/978-3-032-08407-1_19

Series active filters - Spice simulation

Z. Puklus Balázs Tóth

Publication Name: 11th IEEE International Symposium on Computational Intelligence and Informatics Cinti 2010 Proceedings

Publication Date: 2010-12-01

Volume: Unknown

Issue: Unknown

Page Range: 229-231

Description:

Active filters are known as the best tools for harmonic mitigation as well as reactive power compensation, load balancing, voltage regulation, and voltage flicker regulation on the power lines. To introduce the operation of active filters in education, it is a good method to use a software, named SPICE. It is a good choice, because it has a high level of objects for simulation, and good presentation objects for visualizing the results. Students can easily change the parameters of the operation, and can see the its result instead of using real power electronics circuits. In this paper we would like to use a series active filter as the power factor corrector for a "capacitive input" circuit. ©2010 IEEE.

Open Access: Yes

DOI: 10.1109/CINTI.2010.5672244