bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Evaluation of an AI-Based Chatbot for Preventing Social Media Addiction: A Waterfall Model Approach
Authors: Kusumawaty Ira , Yunike  , Fadly  , Kurniawan Tri Basuki
Published: October 2024

The rapid growth of social media has transformed interaction and communication patterns, but it has also led to the rise of social media addiction, particularly among teenagers and young adults. This addiction, marked by compulsive usage and negative impacts on mental health and daily life, necessitates effective interventions. This research explores the development and evaluation of an AI-based chatbot designed to mitigate social media addiction by employing cognitive and behavioural strategies. The study utilizes the Waterfall model—a structured, sequential approach—in the chatbot’s development, encompassing stages from needs analysis to maintenance. The chatbot’s effectiveness was assessed through rigorous testing and user feedback. The methodology included problem analysis, system design, implementation, testing, and iterative improvements. A comprehensive needs analysis identified the psychological and behavioural factors contributing to social media addiction, leading to the design of a prototype chatbot integrated with AI for dynamic content adaptation and real-time feedback. The implementation phase focused on coding and system integration, followed by rigorous testing using Black Box Testing and the System Usability Scale (SUS) to ensure functionality and user-friendliness. Results indicate that the chatbot significantly reduced social media addiction scores, with a mean decrease from 55.21 to 50.17, supported by a highly significant p-value of <0.0001. User satisfaction was high, particularly regarding ease of use and information quality. However, user engagement declined over time, highlighting the need for ongoing content updates and feature enhancements. This study contributes to the field by providing insights into the application of the Waterfall model in AI chatbot development and offers a scalable solution for addressing social media addiction, with implications for future digital interventions in mental health.
Stability Analysis and Optimal Control for Spreading Typhoid Fever Model with Direct and Indirect Transmissions
Authors: Toaha Syamsuddin , Rustam Ilmi Nurfaizah , Kasbawati Kasbawati , Siduppa Muh. Nursyam , Mohamed Siddik Sarinah Banu
Published: October 2024

This article discusses a model of spreading typhoid fever with direct and indirect transmissions. There are five compartments included in the model, namely susceptible individuals, infected individuals, chronic carrier individuals, recovered individuals, and salmonella typhi bacteria in the environment. As an effort to control and minimize the numbers of infected individuals and chronic carrier individuals, we introduce simultaneously campaign for the susceptible individuals and treatment for the infected individuals and for chronic carrier individuals. The resulting model is a system of non-linear differential equations and quite challenging to analysis globally. Existence of both disease-free equilibrium point and endemic equilibrium point are analysed analytically. Stability of the equilibrium point is analysed locally by determining the eigenvalues of the associated Jacobian matrix, Routh-Hurwitz stability criteria, and basic reproduction number () via next generation matrix. The minimum Pontryagin principle and Hamiltonian equation are referred to minimize the numbers of infected and chronic carrier individuals. Simulation is carried out using suitable values of parameters. We found that the eigenvalues for endemic equilibrium point are all negative real numbers and . Optimal paths for state and constate variables are plotted using fourth order forward-backward Runge-Kutta method. In case there are no campaign and treatments, we found  and endemic occurs. When campaign and treatments are included together in the model, we found optimal paths for all compartments that minimize the number of infected and chronic carrier individuals. Giving campaign and treatments increase significantly the susceptible and recovered individuals. At the same time, it reduces significantly the infected, chronic carrier individuals, and salmonella typhi bacteria in the environment. Involving campaign and treatment in the model of spreading typhoid fever can be considered as an effective strategy to minimize the numbers of infected and chronic carrier individuals.
Mathematical Model for MHD Micropolar fluid in with Chemical Reaction towards an Exponential Curved Surface
Authors: Ch.Srinivasulu  , D.V.N.S.R.Murthy  , P.R.Sobhana Babu  , srinivas Diddi  , A.Kiran Kumar  , N.Ravindra
Published: October 2024

The current article delineates the aspects of MHD Micropolar fluid flow with chemical reaction towards an exponentially stretchable curved surface. Aspects of heat transmission are delineated by incorporating joule heating and thermal radiation and viscous Dissipation. To frame the mathematical model, curvilinear co-ordinates are employed. Similarity variables are deployed to transfigure the flow modelling PDE’s into ODE’s. A familiar numerical approach namely Keller box method is operated to resolve the resultant ODE’s. Influence of diverse parameters such as material parameter, curvature parameter, magnetic parameter and chemical reaction parameter has been scrutinized via graphical way. Velocity and Microrotation velocity exhibits unlike nature for magnetic parameter .Temperature exhibits similar response according to variations in , and .Temperature exhibits alike functioning according to variations in , and .Concentration exhibits improvement for variations in and while it decreases for variations in , Sc and .An adequate resemblance has been detected with existing results.
Multi-granularity self-attention mechanisms for few-shot Learning
Authors: Jing Wang , Lim Chia S.
Published: October 2024

Few-shot learning aims to classify novel data categories with limited labeled samples. Although metric-based meta-learning has shown better generalization ability as a few-shot classification method, it still faces challenges in handling data noise and maintaining inter-sample distance stability. To address these issues, our study proposes an innovative few-shot learning approach to enhance image features' global and local semantic representation. Initially, our method employs a multiscale residual module to facilitate extracting multi-granularity features within images. Subsequently, it optimizes the fusion of local and global features using the self- attention mechanism inherent in the Transformer module. Additionally, a weighted metric module is integrated to improve the model's resilience against noise interference. Empirical evaluations on CIFAR-FS and MiniImageNet few-shot datasets using 5-way 1-shot and 5-way 5-shot scenarios demonstrate the effectiveness of our approach in capturing multi-level and multi-granularity image representations. Compared to other methods, our method improves accuracy by 2.63% and 1.27% for 5-shot scenes on these two datasets. The experimental results validate the efficacy of our model in significantly enhancing few-shot image classification performance.
Management Mechanisms of Rehabilitation Hospitals in Bulgaria. Short Communication
Authors: Kasova Emilia A. , Kulchitskaya Detelina B.
Published: October 2024

In a market economy and financial crisis, the head of any medical institution has to make adequate decisions regarding the cost-effective functioning of the hospital. Along with reducing costs, the main task is to maintain a high level of medical care. In this paper, the economic efficiency of medical activities in three specialized hospitals for rehabilitation (previously called sanatoriums) in the cities of Hisar, Varna and Bankia in Bulgaria was studied. The competitiveness of the presented rehabilitation institutions lies in their ability to design, produce and offer rehabilitation services that are more attractive to patients in terms of price and quality characteristics and more fully meet their needs compared to the rehabilitation services of competitors. Based on the analysis, it was found that in rehabilitation hospitals, through long-term obligations, the purchase of short-term assets necessary for the implementation of activities is financed, and operating income is invested in long-term assets. This fact determines the increase in liabilities to the company by further minimizing free cash flows, which involve financing current activities, but are invested in non-current assets. At the same time, rehabilitation hospitals — budgetary organizations strictly comply with capital expenditures, which must be specified in the appropriate paragraph, with an approved budget according to the appropriate indicator, which proves strict compliance with budgetary discipline and control over the flow of funds.
Myelodysplasia Rehabilitation in Children: a Review
Authors: Nekrasova Anna M. , Bodrova Rezeda A. , Nefedeva Darya L.
Published: October 2024

INTRODUCTION. 1.5 thousand children with myelodysplasia (MD) are born in Russia every year. To improve the quality of life, most of them need lifelong medical supervision and rehabilitation. The topic of medical rehabilitation in MD in children is poorly covered.
AIM. To search and analysis published data on the rehabilitation of children with MD identify the most effective methods.
MATERIALS AND METHODS. The collection and analysis of publications on this topic from the PubMed and eLibrary databases published from 2014 to 2024 was carried out. Earlier fundamental works on secondary disorders in myelodysplasia and Spina bifida were also included in the review. A total of 512 publications in PubMed and 1096 publications in eLibrary were analyzed, 584 of them were unique. Publications of reviews, systematic reviews and clinical observations were included.
RESULTS AND DISCUSSION. Rehabilitation for MD in children is multidisciplinary in nature, a violation of the structure of the nervous system entails, already in utero, the formation of deformities of the musculoskeletal system, combined changes in the functioning of the lower urinary tract and intestines. It is known that rehabilitation started from an early age helps to master motor skills in a timely manner, contributes to the prevention of metabolic syndrome, contractures, pressure sores, urodynamic disorders and constipation. There are different approaches regarding the intensity of physical activity during the day and week, following the recommendations of the World Health Organization (WHO), children should exercise for more than 60 minutes a day. Physical exercises should be carried out from the perspective of the concept of neuroplasticity and enhanced by the influence of magnetic stimulation, low-intensity laser, electromyostimulation, vibration therapy. It will be possible to effectively use acupuncture and massage. In addition, it is important to include urological and orthopedic care in medical rehabilitation from an early age.
CONCLUSION. Due to the high disability, there is a question of effective methods for improving rehabilitation potential and improving the standard of living. Among the described methods, physiotherapy is distinguished, including therapeutic exercises, magnetic stimulation, low-intensity laser therapy, electromyostimulation, and ergotherapy. It is necessary to continue to study the effectiveness of the use of various physical factors in children with MD.
O fenómeno da automedicação entre universitários: uma análise dos fatores influenciadores e impactos na saúde
Authors: Ribeiro Darlan de Melo , Mendonça Larissa Aguiar de
Published: October 2024

Introdução: Verificar quais os fatores que influenciam no uso de medicamentos sem a recriação médica pelos acadêmicos universitários, principalmente na área da saúde. Objetivo: Mencionar os fatores que levam os acadêmicos a automedicação e identificar a prevalência da automedicação entre universitários e promover uma educação e saúde, relatando sobre as reações adversas que possam ocorrer. Metodologia: Para a busca dos artigos, foram utilizados periódicos indexados nos bancos de dados da Biblioteca Virtual em Saúde (BVS), PubMed e Google Acadêmico, sustentada pelo banco de dados de artigos e revista foi o Índice Bibliográfico tendo as seguintes palavras chaves Automedicação; Educação em Saúde; Acadêmicos; Saúde; Reações Adversas. Quantos aos critérios de inclusão definidos foram: trabalhos publicados no período de 2019 a 2024, disponíveis na íntegra para pesquisa, escritos no idioma português, inglês e que aborde a temática. Resultados: estão apresentados os estudos que levam os estudantes a se automedicarem, e promovendo uma educação a fazer uso racional de medicamentos. Conclusão: Conclui-se que há um índice elevado de acadêmicos que se automedicam, tornando essencial uma reflexão aprofundada sobre essa prática. É crucial que os profissionais da saúde, adotem o uso racional de medicamentos, promovendo uma abordagem mais segura e responsável.
O uso indiscriminado do Ozempic® para fins estéticos: uma revisão de literatura
Authors: Rodrigues Williane Lima , Silva Tallyson Menezes Bento da
Published: October 2024

Introdução: A busca pelo emagrecimento tornou-se comum na sociedade contemporânea, no qual diversas pessoas desejam atingir um determinado padrão estético. Muitos fazem uso do OZEMPIC®, um medicamento prescrito para o tratamento do diabetes tipo 2. Porém, esta prática pode acarretar sérios problemas em pacientes não diabéticos, o que requer atenção e monitoramento cuidadoso. Objetivo: Realizar uma revisão de literatura acerca do uso off-label do OZEMPIC® (semaglutida) para perda de peso, enfocando os efeitos colaterais, a importância do acompanhamento farmacêutico, e os riscos do uso indiscriminado para fins estéticos. Método:  Foi realizado um levantamento da literatura nas bases de dados: Scientific Electronic Library Online (SCIELO), Biblioteca Virtual em Saúde (BVS) e PubMed. Só foram validados trabalhos no idioma potuguês e inglês publicados durante o período de 2019 a 2024. Resultados: Foram encontrados 11 artigos relevantes sobre as tendências e popularidade do uso off-label de Ozempic®, impactos na saúde e segurança do uso off-label, aspectos regulatórios e práticas profissionais, além do conhecimento, atitudes e supervisão na prescrição. Conclusões: O uso off-label de Ozempic® para perda de peso estética cresce nas redes sociais, mas com pouca conscientização sobre os riscos à saúde.
Investigation on Kinds of Infrastructure Available for Projects Implementation in Public Secondary Schools
Authors: O. Rashid Nuru , A. Nihuka Kassimu
Published: October 2024

The study was concerned with investigating the kinds of infrastructure available for projects implementation in public secondary schools in the West ‘A’ District of Zanzibar. The study employed descriptive survey research design. The target population comprised teachers and heads of schools. Sample size for this study was 255 respondents. Structured questionnaires and semi- structured interviews were used for data collection. Collected quantitative data were analyzed by using descriptive statistics (mean and standard deviations) while qualitative data were analyzed on data deduction technique. The study reveals significant variability in the availability of infrastructure necessary for project implementation in public secondary schools. While some schools have essential resources like computer labs and garden areas, many lack crucial facilities such as sports areas and technological support. The absence of established project timelines highlights a need for better project management practices. It is recommended that the district prioritize the equitable distribution of essential facilities, such as sports areas and technological support, across all public secondary schools. Additionally, implementing structured project management practices, including established timelines and regular progress assessments, will enhance the effectiveness and efficiency of infrastructure development and maintenance.
Enhancing Proficiency: Evaluating Criminology Students' Competency in Security Services NC II for Certification
Authors: Virginia B. Jimmy Cristina , P. Ayeo-Eo Shirley
Published: October 2024

Security services are crucial in protecting individuals, properties, and communities. The field has evolved significantly, with an increase in private security personnel and opportunities for criminology professionals. This study aims to evaluate the confidence and proficiency of criminology students in achieving the Security Services NC II certification. The study employs a quantitative-descriptive design; a self-made questionnaire was used to gather data from 128 respondents. The survey includes self-perceived confidence, knowledge, and skills proficiency regarding security services competencies. Findings revealed that most respondents are confident and rate their proficiency as excellent or good in all competency areas. However, there are indications of needing more proficiency, particularly in marksmanship, report writing, and communication skills. In conclusion, while overall confidence and proficiency are positive, gaps have been identified to address and enhance proficiency in security services.
Awareness, Knowledge and Attitude of Dental Professionals Regarding the Role of CPP-ACP in Caries Prevention – A Questionnaire study
Authors: Jagdish Pusa , Shetty Priya , Thomas Ann , Raj K Deepak , Shetty Smita , S Nishma
Published: October 2024

Background The goal of modern dentistry is to manage non- cavitated caries lesions non-invasively through remineralization in an attempt to prevent disease progression and improve aesthetics, strength, and function. CPP-ACP provides a new direction to preventive dentistry.  Aim To assess the knowledge and attitude among the dentists regarding CPP-ACP as a preventive paradigm.  Material and methods 250 dentists were included in the questionnaire survey. The questionnaire contained 21 close-ended questions. Validated questionnaire on google forms was circulated among the participants via social media. Data from Google forms was entered into excel sheets and SPSS 23 software was used for inferential analysis.  Results Among the 250 dentists, 123 were postgraduates, 83 were general practitioners and 44 were interns. The Postgraduate practitioners (49%) had better knowledge about the basics of CPP-ACP followed by general practitioners (33%) and interns (18%).  Conclusion Most of the dentists are aware about CPP-ACP as a remineralizing agent, but its use is limited in their practice.CPP-ACP should be integrated in the dental practice and newer protocols should be formulated to include CPP-ACP as a preventive strategy in caries prevention.
Minimizing Business Disruption During Enterprise End-Point OS Upgrade while Maintaining a Robust Security Posture
Authors: Almuhaidib Nora , Alduzaz Atheer , Alduzaz Atheer
Published: October 2024

The deployment of a major end-point operating system (OS) upgrade presents significant challenges for enterprise organizations, requiring a comprehensive strategy to minimize business disruption and maintain a robust security posture. Beyond the operational complexities of managing user productivity and application compatibility, organizations must also proactively address the critical security risks associated with such large-scale technology transitions. Cybercriminals often target organizations undergoing major IT changes, seeking to exploit vulnerabilities that may arise due to shifts in the OS architecture, user workflows, and security controls. This paper outlines practical strategies for executing successful OS upgrade projects that balance operational resilience and cyber risk management. Key focus areas include proactive management of end-point security, comprehensive contingency planning and rollback procedures, strategies to sustain productivity and business continuity, effective end-user training and communication, and valuable insights into the next- generation OS deployment. By focusing on these critical aspects, organizations can navigate major OS upgrade initiatives while preserving vigorous business operations, enhancing end-user experience, and safeguarding sensitive data and systems from costly security incidents.
Zwarte vlucht'. De suburbanisatie van Surinamers uit Rotterdam
Authors: Burgers Jack , van der Lugt Hugo
Published: October 2024

Surinamers verlaten de stad Rotterdam in een zelfde omvang, in dezelfde richtingen om de dezelfde redenen als autochtone Nederlanders. Gezien de woonvoorkeurvan minderheidsgroepen als Turken en Marokkanen lijkt het erop dat vertrekkende Surinamers een voorhoede vormen in een ‘zwarte vlucht’: de suburbanisatie van maatschappelijk geslaagde migranten.
De verleiding van geweld
Authors: Mart-Jan de Jong , Willem Schinkel
Published: October 2024

De sociaal-wetenschappelijke bestudering van geweld is veelal deterministisch van aard: externe causale factoren worden verondersteld geweld te verklaren. Een formalistische analyse let daarentegen meer op het bestaan van autotelisch geweld, ofwel geweld om het geweld zelf. Een kwantitatieve analyse van de zelf gerapporteerde affiniteit met geweld laat een sterk verband zien met het plegen van geweld. Geweld lijkt daarom tevens plaats te vinden om redenen die intrinsiek aan geweld zelf zijn.
Tussen dwang en dialoog: maatschappijoriëntatie in inburgerinscursussen
Authors: Iris Van Huis , Ali de Regt
Published: October 2024

Maatschappijoriëntatie maakt deel uit van de inburgeringscursus die nieuwkomers in Nederland verplicht moeten volgen. In dat onderdeel maken immigranten kennis met normen, waarden, opvattingen en gedragsstandaarden die in Nederland belangrijk worden gevonden. Hiertoe behoren thema’s als grondwettelijke rechten en plichten, gezins- en sekseverhoudingen, opvoeding, burgerschapsplichten en Nederlandse zeden en gebruiken. Deze normen worden in de lessen op een open, relativerende en niet-dwingende manier gebracht. De auteurs vragen zich af of inburgeringscursussen niettemin gezien kunnen worden als een nieuw beschavingsoffensief.
Reflectiviteit, strijd en het kunstwerk in Pierre Bourdieus kunstsociologie: enkele kanttekeningen vanuit empirische observaties
Authors: Pascal Gielen
Published: October 2024

De Franse socioloog Pierre Bourdieu heeft een belangrijke stempel op de kunstsociologie gedrukt. In dit artikel plaatst Pascal Gielen vanuit empirische bevindingen enkele kanttekeningen bij de premissen die Bourdieus veldtheorie veronderstelt. De auteur eindigt met een pleidooi voor een meer symmetrische kunstsociologie die een beter evenwicht vindt tussen onderzoekers en onderzoekssubjecten, tussen empirie en theorie, en last but not least: tussen mensen en kunstwerken.
Postmulticulturalisme en stedelijk burgerschap: over de neoliberale transformatie van het Amsterdamse integratiebeleid
Authors: Justus Uitermark , Frank van Steenberge
Published: October 2024

Met behulp van een institutionele en discoursanalyse van het Amsterdamse gemeentelijk beleid kijken Uitermark en Van Steenbergen hoe de kritiek op het multiculturalisme de positie van migrantenorganisaties heeft beïnvloed. Kijkend naar discursieve veranderingen zien de auteurs een verschuiving van minderhedenbeleid naar diversiteitsbeleid, waarbij niet langer etnische organisaties maar interculturele projecten worden gewaardeerd. In combinatie met de opkomst van een neoliberaal stadsbestuur leidt dit tot drastische veranderingen in de machtsrelaties binnen de civil society: de positie van gemeenschappen met weinig mobilisatiekracht wordt nog verder verzwakt.
Novice teachers’ challenges and strategies in coping with COVID-19 at a rural school
Authors: Mbhele Thobeka
Published: October 2024

The study was undertaken to investigate and understand the challenges and strategies of novice teachers in coping with COVID-19 at a rural school. The researcher observed and experienced many challenges during the first year of teaching, including stress, anxiety, depression, lack of support, and lack of collaboration with teammates. This study explores the challenges faced by novice teachers in coping with the COVID-19 pandemic at a rural school. The study employed a qualitative approach, interpretive paradigm, and case study design. Four high school novice teachers participated in this study. Guided by ethical considerations in research, semi-structured interviews were used to collect data. This study used narrative analysis to analyse data from the participants. This study found overcrowded classrooms, heavy workloads, lack of resources, lack of support, tribalism, lack of orientation, lack of discipline, lack of knowledge of subject content, and pressure from school administration as challenges encountered by novice teachers during COVID-19. This study also revealed frustration, discouragement, Insomnia, and mood swings as the effects affecting novice teachers’ well-being. In conclusion, novice teachers applied different strategies to deal with challenges during COVID-19. The Department of Education in Free State should provide mobile classrooms so learners are comfortable and enjoy the lesson, and teachers can also move around when presenting a lesson. The government must develop supportive social networks and proper orientation for novice teachers to limit the lack of support.
Basotho learners’ challenges affect effective learning in a rural high school during the COVID-19 era
Authors: Mantwa Mofokeng
Published: October 2024

The learning process depends on decisions and constant assessments obtained from what is learned and how it is learned, the support given to access knowledge or concepts, and whether what is remembered by learners is correct. However, this process was disrupted in the COVID-19 era as there was rapid spread of COVID-19. This study investigates the challenges influencing effective learning among Basotho learners in a rural high school in the Mofutsanyane District. This study used a qualitative approach through a case study design. Participants were chosen purposefully, including the learners, parents or guardians, teachers, school governing body, school-based support team, and school management team members. Data were collected through in-depth semi-structured interviews. The narrative results indicated that Basotho learners encountered various challenges, including failure of learners to attend online classes, absenteeism, poor internet connection, and declining performance. They experienced academic pressure, inadequate curriculum coverage, a knowledge gap in the next grade, and the learners transitioning to virtual learning. All these challenges affected learners' learning process due to transiting, which had to happen and did not favour all the learners’ family backgrounds.
Fostering an enabling environment for Learners with Special Needs in rural primary schools in Lesotho
Authors: Lebona Mathabo , Monyane Mohapi  Augustinus , Mukuna Kananga Robert
Published: October 2024

Successful inclusion of Learners with Special Educational Needs in mainstream teaching and learning is a challenge globally. This study explores fostering an enabling environment for Learners with Special Educational Needs in rural primary schools in Lesotho. Data for the study were collected using a qualitative approach using a case study design, and analysis was done through Thematic Analysis. Thirteen teachers from two primary schools in the rural community and two officials from the Ministry of Education and Training purposively were selected in Lesotho and participated in this study. Focus group discussions and one-on-one semi-structured interviews were used as instruments for data collection. Thematic results showed that teachers’ inflexibility hindered the creation of an enabling environment in terms of infrastructure and poor allocation of resources, which were critical challenges to support LSEN in their daily teaching and learning activities. The results revealed that not enabling environments and the unavailability of relevant resources increase the number of dropouts in schools among LSEN. The results further revealed that the lack of pertinent training for regular teachers to help special education learners succeed effectively handicapped the education of LSEN in mainstream teaching and learning. Therefore, the study recommends that teachers be given continuous workshops by MoET and in-service training to fill the gaps in special education programmes and produce teachers who can be relevant in inclusive teaching and learning in Lesotho's primary mainstream schools, particularly rural schools.
Teachers’ and principals’ challenges in implementing Life Skills Education at secondary schools in Lesotho
Authors: Tsiu Nthofela
Published: October 2024

Lack of training complicates the teaching and learning process. This study explores teachers' and principals’ challenges in implementing Life Skills Education (LSE) at secondary schools in Lesotho. Few graduate teachers received short-term training on LSE; hence, most teachers already practising in schools cannot teach LSE. The findings also revealed that teachers encountered challenges implementing LSE in Lesotho secondary schools. The results indicated that teachers feel troubled when teaching LSE for multiple reasons. These include the lack of skills of unqualified teachers and teachers' lack of confidence and interest. As a result, teachers turn to inappropriate teaching methods. The results indicated that sexuality education and HIV and AIDS could challenge the delivery and implementation of LSE schools. Thus, teachers need to acquire appropriate training and teaching methods in LSE.
Exploring selective learning in enhancing effective learning interest among grade 10 learners in schools in the Motheo district
Authors: Mabulana Katlego , Mukuna Kananga Robert
Published: October 2024

Teaching and learning in South Africa has been a concern. Schools have inflexible curriculum to accommodate learning interests of the learners. This causes numerous disadvantages to learners, such as dropping out, unstable teaching and learning environments, lack of readiness for higher education, and many more. The study explores how selective learning could enhance effective learning interest among grade 10 learners at schools in the Motheo district, Free State province, South Africa. Selective learning is the learner’s decision to select and learn relevant subjects within the curriculum framework, guided by one’s learning interest. This study adopted a qualitative approach and used a qualitative case study research design and interpretive paradigm. Semi-structured interviews with open-ended questions were used as a data collection instrument. Eight participants were purposively selected from two high schools. Participants were teachers from rural and urban-based schools with more than two years of teaching experience. Thematic analysis was used to analyse qualitative data. The results showed that selective learning could enhance effective learning interest by creating tolerable learning, enhancing cognitive skills, engaging teaching and learning, and creating academic excellence. Thus, this study concludes that selective learning can enhance effective learning interest among grade 10 learners in schools in the Motheo district of the Free State province.
Supporting learners with autism spectrum disorders in Lesotho primary schools: Challenges and possible solutions
Authors: Monyane Mohapi  Augustinus
Published: October 2024

Supporting learners with Autism Spectrum Disorders (ASD) in schools is one of the vital responsibilities of teachers. This paper focused on exploring the challenges encountered by teachers in fulfilling their role of supporting learners with ASD within mainstream primary school settings in Lesotho and designing strategies that can overcome these challenges. This qualitative study draws on a purposive sample of fourteen participants (two principals, six teachers, and six parents) who have experience working with learners with ASD within two primary schools that practice inclusive education in Lesotho. Data were collected with individual interviews and observations to conduct an in-depth investigation of the study. Thematic results showed that inadequate knowledge in managing the behaviours of learners with ASD, negative attitudes towards learners with ASD, lack of parental involvement, and lack of access to physical, human, and financial resources in primary schools as the significant challenges faced by teachers when supporting learners with ASD in Lesotho regular primary schools. Hence, the paper recommends continuous professional development training workshops and seminars for teachers. Also, there is a need for more autism screening tools and academic resources, as well as effective collaboration among teachers, parents, and professionals to enhance adequate support for learners with ASD in mainstream schools.
The ∼50 Myr Old TOI-942c is Likely on an Aligned, Coplanar Orbit and Losing Mass
Authors: Teng 滕 Huan-Yu 环宇 , Dai 戴 Fei 飞 , Howard Andrew W. , Isaacson Howard , Rubenzahl Ryan A. , Angelo Isabel , Polanski Alex S.
Published: October 2024

We report the observation of the transiting planet TOI-942c, a Neptunian planet orbiting a young K-type star approximately 50 Myr years old. Using the Keck/High Resolution Echelle Spectrometer, we observed a partial transit of the planet and detected an associated radial velocity anomaly. By modeling the Rossiter–McLaughlin effect, we derived a sky-projected obliquity of

λ

=

24

−
14

+
14

degrees, indicating TOI-942c is in a prograde and likely aligned orbit. Upon incorporation of the star’s inclination and the planet’s orbital inclination, we determined a true obliquity for TOI-942c of ψ < 43° at 84% confidence, while dynamic analysis strongly suggests TOI-942c is aligned with stellar spin and coplanar with the inner planet. Furthermore, TOI-942c is also a suitable target for studying atmospheric loss of young Neptunian planets that are likely still contracting from the heat of formation. We observed a blueshifted excess absorption in the Hα line at 6564.7 Å, potentially indicating atmospheric loss due to photoevaporation. However, due to the lack of preingress data, additional observations are needed to confirm this measurement.
Improving Power Spectrum Estimation Using Multitapering: Efficient Asteroseismic Analyses for Understanding Stars, the Milky Way, and Beyond
Authors: Patil Aarya A. , Eadie Gwendolyn M. , Speagle 沈 Joshua S. 佳士 , Thomson David J.
Published: October 2024

Asteroseismic time series data have imprints of stellar oscillation modes, whose detection and characterization through time series analysis allows us to probe stellar interior physics. Such analyses usually occur in the Fourier domain by computing the Lomb–Scargle (LS) periodogram, an estimator of the power spectrum underlying unevenly sampled time series data. However, the LS periodogram suffers from the statistical problems of (1) inconsistency (or noise) and (2) bias due to high spectral leakage. Here, we develop a multitaper power spectrum estimator using the nonuniform fast Fourier transform (mtNUFFT) to tackle the inconsistency and bias problems of the LS periodogram. Using a simulated light curve, we show that the mtNUFFT power spectrum estimate of solar-like oscillations has lower variance and bias than the LS estimate. We also apply our method to the Kepler-91 red giant, and combine it with PBjam peakbagging to obtain mode parameters and a derived age estimate of 3.97 ± 0.52 Gyr. PBjam allows the improvement of age precision relative to the 4.27 ± 0.75 Gyr APOKASC-2 (uncorrected) estimate, whereas partnering mtNUFFT with PBjam speeds up peakbagging thrice as much as LS. This increase in efficiency has promising implications for Galactic archaeology, in addition to stellar structure and evolution studies. Our new method generally applies to time-domain astronomy and is implemented in the public Python package tapify, available at https://github.com/aaryapatil/tapify.
Far-field Pattern Analysis Based on Piecewise Aperture Field Integration for Leighton Chajnantor Telescope Antenna under Gravity and Wind Load
Authors: You Jia , Wang Zheng
Published: October 2024

The Caltech Submillimeter Observatory telescope will be relocated from Mauna Kea, Hawaii to Chajnantor Plateau, Chile, refurbished there and renamed the Leighton Chajnantor Telescope (LCT). At the new site, the open-air environment, as well as the high altitude, will amplify the influence of gravity and wind load on structural deformation, thus affecting the antenna’s radiation characteristics, which can be characterized by a far-field pattern. To quickly and accurately compensate for the effect of reflector structural deformation on the far-field pattern of LCT’s antenna, we propose a far-field pattern quick calculation method (FPQCM) to analyze the antenna’s radiation characteristics under gravity and various wind loads, which combines the optical path difference calculation method on the aperture plane, the piecewise Zernike polynomial function, and the piecewise aperture field integration method. Through extensive experimental comparisons with the numerical method based on physical optics and physical theory of diffraction, it is validated that the proposed FPQCM significantly reduces the time by more than 100 times for acquiring the far-field patterns while maintaining the accuracy of the main figure of merits at the highest frequency (i.e., 856 GHz). In addition, we analyzed the far-field pattern of the antenna at different zenith angles, gravity, and winds of different strengths and directions by FPQCM, which provided guidance for performing more precise control through an active surface optimization system after LCT resumes operation, thus facilitating the acquisition of higher surface accuracy and better observation effect.
Exploring the Broadband Spectral and Timing Characteristics of GRS 1915+105 with AstroSat and NICER Observations
Authors: Dhaka Ruchika , Misra Ranjeev , Jain Pankaj , Yadav J. S.
Published: October 2024

In this study, we undertake a spectral-timing analysis of the black hole X-ray binary source GRS 1915+105 using simultaneous observations carried out by AstroSat (Large Area X-ray Proportional Counter, LAXPC and Soft X-ray Telescope, SXT) and Neutron Star Interior Composition Explorer (NICER) in 2017. The source showed two flux levels (high and low), whose energy spectra can be described by the thermal comptonization of disk photons. The spectral parameters obtained by the joint fitting of SXT/LAXPC and NICER/LAXPC were consistent. The power density spectra from LAXPC and NICER revealed a broad, prominent feature at ∼2 Hz. The energy dependence of the fractional rms and time lag of this feature cannot be explained by only variations of coronal spectral parameters. Instead, a model where the coronal heating rate varies first and induces a change in the disk temperature and inner radius can explain the variation. Our results underline the importance of simultaneous observations by AstroSat and NICER and highlight the need for more sophisticated models to explain the spectral-temporal behavior of black hole systems.
IllustrisTNG in the HSC-SSP: No Shortage of Thin Disk Galaxies in TNG50
Authors: Xu 徐 Dewang 德望 , Gao 高 Hua 桦 , Bottrell Connor , Yesuf Hassen M. , Shi Jingjing
Published: October 2024

We perform a thorough analysis of the projected shapes of nearby galaxies in both observations and cosmological simulations. We implement a forward-modeling approach to overcome the limitations in previous studies, which hinder accurate comparisons between observations and simulations. We measure axis ratios of z = 0 (snapshot 99) TNG50 galaxies from their synthetic Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) images and compare them with those obtained from real HSC-SSP images of a matched galaxy sample. Remarkably, the comparison shows excellent agreement between the observations and the TNG50 simulation, challenging previous claims that ΛCDM models underproduced the abundance of thin galaxies. Specifically, for galaxies with stellar masses

10
≤
log
(

M

⋆

/

M

☉

)
≤
11.5

, we find ≲0.1σ tensions between the observations and the simulation, a stark contrast to the previously reported ≳10σ tensions. We reveal that low-mass galaxies

(

M

⋆

≲

10
9.5

M

☉

)

in TNG50 are thicker than their observed counterparts in HSC-SSP and attribute this to the spurious dynamical heating effects that artificially puff up galaxies. We also find that, despite the overall broad agreement, TNG50 galaxies are more concentrated than the HSC-SSP ones at the low- and high-mass end of the stellar mass range of

9.0
≤
log
(

M

⋆

/

M

☉

)
≤
11.2

and are less concentrated at intermediate stellar masses. But we argue that the higher concentrations of the low-mass TNG50 galaxies are not likely the cause of their thicker/rounder appearances. Our study underscores the critical importance of conducting mock observations of simulations and applying consistent measurement methodologies to facilitate proper comparison with observations.
Spectroastrometry and Reverberation Mapping of Active Galactic Nuclei. I. The Hβ Broad-line Region Structure and Black Hole Masses of Five Quasars
Authors: Li Yan-Rong , Hu Chen , Yao Zhu-Heng , Chen Yong-Jie , Bai Hua-Rui , Yang Sen , Du Pu , Fang Feng-Na , Fu Yi-Xin , Liu Jun-Rong , Peng Yue-Chang , Songsheng Yu-Yang , Wang Yi-Lin , Xiao Ming , Zhai Shuo , Winkler Hartmut , Bai Jin-Ming , Ho Luis C. , Petrov Romain G. , Aceituno Jesús , Wang Jian-Min ,   SARM Collaboration
Published: October 2024

We conduct a reverberation mapping (RM) campaign to spectroscopically monitor a sample of selected bright active galactic nuclei with large anticipated broad-line region (BLR) sizes adequate for spectroastrometric (SA) observations by the GRAVITY instrument on the Very Large Telescope Interferometer. We report the first results for five objects, IC 4329A, Mrk 335, Mrk 509, Mrk 1239, and PDS 456, among which Mrk 1239 and PDS 456 are for the first time spectroscopically monitored. We obtain multiyear monitoring data and perform multicomponent spectral decomposition to extract the broad Hβ profiles. We detect significant time lags between the Hβ and continuum variations, generally obeying the previously established BLR size–luminosity relation. Velocity-resolved Hβ time lags illustrate diverse, possibly evolving, BLR kinematics. We further measure the Hβ line widths from mean and rms spectra and the resulting virial products show good consistency among different observing seasons. Adopting a unity virial factor and the FWHM of the broad Hβ line from the mean spectra as a measure of velocity, the obtained black hole masses averaged over seasons are

log

M

•

/

M

⊙

=

8.02

−
0.14

+
0.09

,

6.92

−
0.12

+
0.12

,

8.01

−
0.25

+
0.16

,

7.44

−
0.14

+
0.13

, and

8.59

−
0.11

+
0.07

for the five objects, respectively. Black hole mass estimations using other line width measures are also reported. For objects with previous RM campaigns, our mass estimates are in agreement with earlier results. In a companion paper, we will employ BLR dynamical modeling to directly infer the black hole mass and thereby determine the virial factors.
NuSTAR Observation of the TeV-detected Radio Galaxy 3C 264: Core Emission and the Hot Accretion Flow Contribution
Authors: Wong Ka-Wah , Steiner Colin M. , Blum Allison M. , Lin Dacheng , Nemmen Rodrigo , Irwin Jimmy A. , Wik Daniel R.
Published: October 2024

3C 264 is one of the few FRI radio galaxies with detected TeV emission. It is a low-luminosity active galactic nucleus (LLAGN) and is generally associated with a radiatively inefficient accretion flow (RIAF). Earlier multiwavelength studies suggest that the X-ray emission originates from a jet. However, the possibility that the RIAF can significantly contribute to the X-rays cannot be ruled out. In particular, hard X-ray emission ≳10 keV has never been detected, making it challenging to distinguish between X-ray models. Here we report a NuSTAR detection up to 25 keV from 3C 264. We also present subpixel deconvolved Chandra images to resolve jet emission down to ∼0.″2 from the center of the unresolved X-ray core. Together with a simultaneous Swift observation, we have constrained the dominant hard X-ray emission to be from its unresolved X-ray core, presumably in its quiescent state. We found evidence of a cutoff in the energy around 20 keV, indicating that at least some of the X-rays from the core can be attributed to the RIAF. The Comptonization model suggests an electron temperature of about 15 keV and an optical depth ranging between 4 and 7, following the universality of coronal properties of black hole accretion. The cutoff energy or electron temperature of 3C 264 is the lowest among those of other LLAGNs. The detected hard X-ray emission is at least an order of magnitude higher than that predicted by synchrotron self-Compton models introduced to explain γ-ray and TeV emission, suggesting that the synchrotron electrons might be accelerated to higher energies than previously thought.
Unraveling the Hybrid Origins of the X-Ray Nonthermal Emission from IGR J17091–3624
Authors: Lin Zikun , Wang Yanan , del Palacio Santiago , Méndez Mariano , Zhang Shuang-Nan , Russell Thomas D. , Ji Long , Zhang Jin , Zhang Liang , Altamirano Diego , Liu Jifeng
Published: October 2024

We present a comprehensive study based on multiwavelength observations from the NuSTAR, NICER, Swift, Fermi, NEOWISE, and ATCA telescopes during the 2022 outburst of the black-hole X-ray binary IGR J17091–3624. Our investigation concentrates on the heartbeat-like variability in the X-ray emission, with the aim of using it as a tool to unravel the origin of the nonthermal emission during the heartbeat state. Through X-ray timing and spectral analysis, we observe that the heartbeat-like variability correlates with changes in the disk temperature, supporting the disk radiation pressure instability scenario. Moreover, in addition to a Comptonization component, our time-averaged and phase-resolved spectroscopy reveal the presence of a power-law component that varies independently from the disk component. Combined with the radio–X-ray spectral energy distribution fitting, our results suggest that the power-law component could originate from synchrotron self-Compton radiation in the jet, which requires a strong magnetic field of about B = (0.3–3.5) × 106 G. Additionally, assuming that IGR J17091-3624 and GRS 1915 + 105 share the same radio–X-ray correlation coefficient during both the hard and the heartbeat states, we obtain a distance of 13.7 ± 2.3 kpc for IGR J17091–3624.