bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Amino Acid Supplementation on the Growth Performance of Broiler Chicks Challenged With Coccidiosis: A Meta‐Analysis
Authors: Izadi Yazdanabadi Fatemeh , Moghaddam Gholamali , Abbasabadi Mehdi , Akbari Mohsen , Mohammadi Bahram Satlikh , Khosravi Parvin , Sabzekar Hossein , Farrokhi Reza
Published: December 2024

This meta‐analysis aimed to evaluate the effects of amino acid supplementation on the growth performance of broiler chicks challenged with coccidiosis. Data were collected on authorship, publication year, study sample characteristics and outcomes of interest related to growth performance. Effect sizes were calculated for both overall effects and the individual effects of each amino acid. The effects of moderator factors, such as supplementation levels and duration, were also assessed, and bias was calculated. Works were obtained from PubMed, Elsevier, ScienceDirect, Wiley, Springer Link and Scopus databases, with the help of search engines like Google Scholar and ResearchGate, covering the period from 2013 to 2023. A random‐effects model was used. Thirteen works were included in the current analysis, examining the effects of arginine (n = 4), methionine (n = 6), threonine (n = 3) and glutamine (n = 3). Amino acid supplementation [0.326, CI 95% (0.297–0.355); p = 0.000], arginine [0.430, CI 95% (0.293–0.568); p = 0.000] and threonine [0.793, CI 95% (0.193–1.38); p = 0.009] significantly increased body weight. Amino acid supplementation [0.052, CI 95% (0.022–0.081); p = 0.000] and arginine [0.317, CI 95% (0.049–0.585); p = 0.000] also significantly increased feed intake. Higher levels of amino acids (≥1.50%) and longer supplementation periods (≥15 days) significantly increased body weight and feed intake, while reducing the feed conversion ratio. Funnel plots, fail‐safe N and Egger tests showed no evidence of bias. In conclusion, arginine supplementation has the potential to increase body weight and feed intake in poultry challenged with coccidiosis. Higher doses of amino acids and longer supplementation periods are recommended in such cases.
Excessive haemorrhage in a Great Dane with suspected von Willebrand disease following two routine corrective eyelid surgeries
Authors: Bekkat‐Berkani Desislava , Raszplewicz Joanna , Duffy Natalie
Published: December 2024

A 7‐month‐old, male, entire Great Dane was presented for surgical treatment of bilateral scrolled cartilage abnormality of the nictitating membranes with concurrent macroblepharon and early‐entropion complex. The patient underwent two separate surgical interventions and experienced excessive haemorrhage, which was difficult to control after both procedures. A reduction in haemorrhage was observed following the administration of desmopressin acetate infusion. Von Willebrand disease type I was strongly suspected. This report discusses the importance of functional coagulation testing in contrast to reliance on results of prothrombin time and activated partial thromboplastin time clotting assays alone in diagnosing the underlying cause of prolonged surgical haemorrhage in dogs, particularly in breeds with hereditary coagulation disorders. It provides a brief summary on primary and secondary haemostasis, causes for delayed surgical haemorrhage and possible treatment options.
Healthcare Professionals' Experiences From the COVID‐19 Vaccination Program for the Homebound Population in Greece: A Cross‐Sectional Mixed‐Methods National Study
Authors: Papageorgiou Dimitra Iosifina , Vlachopoulos Nikolaos , Gavana Magda , Tahtalidou Zoi , Gialama Marilena , Avakian Ioanna , Ntenta Panagiota , Theodoropoulos Elias , Andreou Martha , Evangelidis Paschalis , Evangelidis Nikolaos , Nteli Despoina , Nteli Maria , Vitoris Ioannis , Avramidou Eleni , Nastas Theofilos , Bapka Aspasia , Zgouridou Aikaterini , Kokkali Stamatia , Ploukou Stella , Symintiridou Despoina , Paganas Aristofanis , Zeimbekis Doukas , Dandoulakis Michael , Giakoumis Anastasios , Haidich Anna Bettina , Smyrnakis Emmanouil
Published: December 2024

During the pandemic, mobile vaccination units administered COVID‐19 shots to homebound populations. This study explores the perspectives of public healthcare providers involved in Greece's COVID‐19 home vaccination program, aiming to identify challenges and inform improvements in delivering healthcare services at home. This is a cross‐sectional mixed‐methods survey with convergent design, conducted in public Primary Health Care facilities, using a questionnaire. Facilities from all Health Districts were invited. The study population included healthcare professionals and administrative staff engaged in vaccination units. Data were collected from April to July 2022. Quantitative data were analyzed using descriptive statistics and univariate linear regression analysis, while qualitative data underwent thematic analysis. Integration at the analysis phase enhanced understanding and reliability. The study was approved by the Bioethics Committee of the Aristotle University of Thessaloniki. A total of 1200 participants from 168 facilities across six Health Districts responded. The majority were nurses (34.1%) and general practitioners (24.7%). Participants unanimously praised the program's concept, aligning it with Primary Health Care and expressed readiness for future involvement, but reported time constraints. Those in larger groups found time management easier (1.68, 95% CI [1.28, 2.20], p < 0.001). Thematic analysis of 1070 text responses identified five themes, including guidance for implementation, resource availability, field challenges, professionals' skillsets, and public engagement. Collaboration with colleagues and authorities to address transportation problems proved vital for success. Understaffing and time constraints were evident. Integrating a new service into busy settings poses challenges, underscoring the need for problem‐solving and empowering healthcare personnel to address shortcomings.
Gleichwertige Lebensverhältnisse: was wir wissen und was nicht
Authors: Lorenz Astrid , Pischtschan Luisa
Published: December 2024

In einer Demokratie ist die Politik „responsiv“ gegenüber der Gesellschaft, d. h. sie reagiert auf deren Wünsche, Vorstellungen und Bedürfnisse. Dies ist eine Grundannahme der Demokratieforschung. Besonders für die in einer Verfassung genannten Anliegen sollte die Responsivitätsannahme zutreffen. Empirisch geprüft wurde dies aber bislang kaum für das in Deutschland verankerte Leitbild, gleichwertige Lebensverhältnisse zu gewährleisten. Wie wir in diesem Kapitel zeigen, ist der Wissensstand, an den Studien zu gleichwertigen Lebensverhältnissen anschließen können, beträchtlich, aber es bedarf mehr Forschung dazu, welche Themen Menschen bei der Beschreibung des Lebens vor Ort bewegen, was sie sich unter gleichwertigen Lebensverhältnissen vorstellen und was sie sich von der Politik wünschen. Zugleich liefert das Kapitel Informationen zur Politik gleichwertiger Lebensverhältnisse in Deutschland, die dabei helfen, die Ergebnisse der nachfolgenden Analyse einzuordnen, und eine Begründung unseres spezifischen Untersuchungsansatzes.
Beschreibungen der lokalen Lebensverhältnisse
Authors: Lorenz Astrid , Pischtschan Luisa
Published: December 2024

Wie lebt es sich vor Ort in Deutschland? Was macht für Menschen ihren Ort aus? Das wollten wir im ersten Teil unserer Gruppendiskussionen von den Teilnehmern in den 24 ausgewählten Kommunen wissen. Wie wir in diesem Kapitel zeigen, beschrieben sie ihren Ort vor dem Hintergrund von Mobilität. Dies könnte ihre Wahrnehmung und Bewertung gleichwertiger Lebensverhältnisse beeinflussen (Abschn. 4.1). Überall zeichneten die Gruppen ein positives Bild vom eigenen Ort und erwähnten sehr ähnliche Aspekte als wichtig für das Leben dort. Dabei bestanden aber teilweise Unterschiede zwischen Großstädten und kleineren Orten hinsichtlich der konkreten Inhalte, die angesprochen wurden (Abschn. 4.2). Die im Nachgang zu den Gruppendiskussionen durchgeführte anonyme Befragung der Teilnehmer bestätigte die überwiegend positive Darstellung des Lebens vor Ort (Abschn. 4.3).
Harnessing Trichoderma Mycoparasitism as a Tool in the Management of Soil Dwelling Plant Pathogens
Authors: Singh Srishti , Singh Alok Kumar , Pradhan Bhubaneswar , Tripathi Sudipta , Kumar Kewat Sanjay , Chand Sasmita , Rout Prangya Ranjan , Shahid Muhammad Kashif
Published: December 2024

Maintaining and enhancing agricultural productivity for food security while preserving the ecology and environment from the harmful effects of toxicants is the main challenge in modern monoculture farming systems. Microbial biological agents can be a promising substitute for traditional synthetic pesticides to manage plant diseases. Trichoderma spp. are soil-dwelling ascomycete fungi and are common biocontrol agents against diverse phytopathogens. Trichoderma-based biocontrol techniques can regulate and control soil-borne plant diseases through mechanisms such as mycoparasitism, the production of antibiotics and hydrolytic enzymes, rhizo-sphere competence, the effective competition for available resources, induction of plant resistance and facilitation of plant growth. Numerous secondary metabolites produced by Trichoderma spp. are reported to prevent the development of soil-borne plant disease. Thus, Trichoderma spp. may have direct and indirect biological impacts on the targeted plant pathogens. Furthermore, this review discusses the convenient implications and challenges of applying Trichoderma-based strategies in agricultural settings. Overall, the assessment underscores the potential of Trichoderma as a sustainable and effective tool for mitigating soil-borne pathogens, highlighting avenues for future research and applications.
Local anaesthesia vs. brachial plexus block in trapeziometacarpal joint arthroplasty
Authors: Moshammer Maximilian , Klim Sebastian Martin , Glehr Reingard , Hauer Georg , Hecker Andrzej , Leithner Andreas , Glehr Mathias
Published: December 2024

Introduction

An established anaesthetic procedure used during total trapeziometacarpal joint (TMCJ) arthroplasty is the brachial plexus block (BPB). It was hypothesized that local anaesthesia (LA) provides advantages in overall cost, enables intraoperative assessment of the prosthesis, and minimises the anaesthetic risk. In this study, LA to BPB was compared and outcomes, safety, and overall patient satisfaction were analyzed.

Materials and methods

In this single-center cohort study, 32 patients (34 operated thumbs) who underwent total TMCJ arthroplasty between February 2018 and July 2021 were included. Two groups were formed depending on the anaesthetic method used. One group was operated under LA, and the other under BPB. Functionality scores were assessed preoperatively and three month postoperatively. Additionally, pain was assessed on the 1st and 12th postoperative day. Data on intraoperative pain and anxiety, overall satisfaction, pain medication use, and willingness to undergo the procedure again were gathered through a retrospective telephone survey.

Results

No significant differences between LA and BPB were found in terms of functional outcomes, pain reduction, and willingness to repeat the procedure. The analysis further showed significant differences in intraoperative anxiety (higher in the LA group; LA 1.69, SD: 2.65; BPB 0.28, SD: 0.58; measured using a numeric rating scale 0–10; p = 0.045), operation length (higher in BPB group; LA 39 min, SD: 7.46; BPB 45 min, SD: 7.02; p = 0.018) and overall setup time (higher in BPB group; LA 76 min, SD: 15.85; BPB 102 min, SD: 19.66; p < 0.001). No conversion from LA to another anaesthetic method was necessary.

Conclusion

The use of LA in total TMCJ arthroplasty is a practical and reliable alternative to the well-established BPB. LA reduces the cost of the procedure, necessity of an anaesthesiology team and the duration of the patients´ hospital stay. Patients should be actively involved in selecting the anaesthetic method to optimize the operative procedure and overall outcome.
Risk analyses for perioperative morbidities after aseptic knee revision arthroplasty
Authors: Abdelghany Ahmed , Migliorini Filippo , Peterlein Christian , Götze Christian , Koettnitz Julian
Published: December 2024

Introduction

Total lower limb arthroplasties are standard orthopedic surgeries that are steadily increasing in modern civilization. In proportion, the number of revision arthroplasties and the corresponding financial burden for healthcare systems will increase. The present clinical investigation analyzed morbidities after aseptic revision knee arthroplasty.

Methods

Data from 122 patients following aseptic revision TKA (total knee arthroplasty) were collected. The study collected information on systemic and surgical complications during hospitalization and follow-up, blood transfusion units, and changes in Hb and CRP levels. Hb and CRP were measured preoperatively and on postoperative days 1, 2, and 4. Statistical analyses were performed using IBM SPSS version 29.

Results

Significant differences were observed in systemic, surgery-related and blood transfusion rates and reasons for knee replacement changes based on age and gender. Of the patients, 38.5% received a full component change, 11.5% received a partial component replacement (either femoral or tibial), 30.3% had an isolated inlay change, and 19.7% underwent debridement only. Femoral and tibial loosening were more frequent in patients over 75 years and those with longer intervals between the initial operation and re-presentation (p = 0.001). Patients with movement deficits and malposition presented earlier for consultation (p = 0.02). Prolonged high CRP levels were significantly correlated with systemic complications, longer hospital stays, and extended operative times.

Conclusions

Aseptic knee revision arthroplasty is a complex procedure with perioperative morbidities that can significantly impact outcomes. Age and gender are crucial factors in managing complications during hospitalization and follow-up. Elderly patients, particularly those over 75 years, are more prone to aseptic loosening and require tailored preoperative preparation. The study underscores the importance of individualized patient care strategies to mitigate risks and improve outcomes in aseptic knee revision arthroplasty.

Trial registration: Not applicable.
Artificial intelligence in pediatric allergy research
Authors: Lisik Daniil , Basna Rani , Dinh Tai , Hennig Christian , Shah Syed Ahmar , Wennergren Göran , Goksör Emma , Nwaru Bright I.
Published: December 2024

Atopic dermatitis, food allergy, allergic rhinitis, and asthma are among the most common diseases in childhood. They are heterogeneous diseases, can co-exist in their development, and manifest complex associations with other disorders and environmental and hereditary factors. Elucidating these intricacies by identifying clinically distinguishable groups and actionable risk factors will allow for better understanding of the diseases, which will enhance clinical management and benefit society and affected individuals and families. Artificial intelligence (AI) is a promising tool in this context, enabling discovery of meaningful patterns in complex data. Numerous studies within pediatric allergy have and continue to use AI, primarily to characterize disease endotypes/phenotypes and to develop models to predict future disease outcomes. However, most implementations have used relatively simplistic data from one source, such as questionnaires. In addition, methodological approaches and reporting are lacking. This review provides a practical hands-on guide for conducting AI-based studies in pediatric allergy, including (1) an introduction to essential AI concepts and techniques, (2) a blueprint for structuring analysis pipelines (from selection of variables to interpretation of results), and (3) an overview of common pitfalls and remedies. Furthermore, the state-of-the art in the implementation of AI in pediatric allergy research, as well as implications and future perspectives are discussed.

Conclusion: AI-based solutions will undoubtedly transform pediatric allergy research, as showcased by promising findings and innovative technical solutions, but to fully harness the potential, methodologically robust implementation of more advanced techniques on richer data will be needed.

What is Known:• Pediatric allergies are heterogeneous and common, inflicting substantial morbidity and societal costs.• The field of artificial intelligence is undergoing rapid development, with increasing implementation in various fields of medicine and research.

What is New:• Promising applications of AI in pediatric allergy have been reported, but implementation largely lags behind other fields, particularly in regard to use of advanced algorithms and non-tabular data. Furthermore, lacking reporting on computational approaches hampers evidence synthesis and critical appraisal.• Multi-center collaborations with multi-omics and rich unstructured data as well as utilization of deep learning algorithms are lacking and will likely provide the most impactful discoveries.
From supportive care to trauma: training integrative practitioners in the treatment of acute stress disorder
Authors: Ben-Arye Eran , Rubinstein Dori , Keshet Yael , Samuels Noah , Stoffman Gali , Lahad Mooli , Reshef Alon , Schiff Elad
Published: December 2024

Objective

The present conflict in Israel has led to a surge in cases of acute stress disorder (ASD). The study examined a training program for integrative medicine (IM) providers working in supportive and palliative care settings, teaching clinical skills for treating ASD.

Methods

A 10-h online training program, designed by supportive care trained IM and mental health professionals was attended by a group of 32 IM providers. The impact of the course was assessed using pre- and post-training questionnaires, which underwent qualitative evaluation. Three open-ended questions addressed expectations from the program, anticipated barriers to combining IM with mental health interventions, and explored willingness for multi-disciplinary collaboration. A conventional content analysis was used, where coding categories are derived directly from the text data. Narratives were analyzed using ATLAS.ti software for systematic coding.

Results

Narrative themes identified within the group of 32 trainees included expectations regarding facilitating a multi-disciplinary integrative model of care, enriching the ASD-related clinical “toolbox,” increasing the effectiveness of IM treatments, and reducing IM treatment-associated risks. Insights were provided for bridging communication gaps between IM practitioners and mental health providers, supporting the multi-disciplinary collaboration.

Conclusions

ASD-focused training for IM practitioners may increase their level of clinical skills and advance collaboration with mental health providers. Future research examining the feasibility of the integrative model and its implementation in supportive care setting is warranted.
Crush injuries to the lower limbs at a major UK trauma centre: a retrospective observational study
Authors: Rama Essam , Jayawant Saania , Zhang James , Krkovic Matija
Published: December 2024

Purpose

Crush injuries result from the physical compression of muscles and may lead to crush syndrome. Early fluid resuscitation and surgical intervention is key. Few studies have reported the outcomes of crush injuries in the non-disaster setting. This retrospective study aims to characterise such cases.

Methods

Patients with lower limb crush injuries were identified from an internal database. Non-crush injuries and patients under the age of 18 were excluded. Types of injuries, management, and complications were extracted.

Results

27 patients were included. The right leg (n = 10) was the most frequently injured site. Mechanisms included being run over by vehicles (n = 10) and being crushed by, between, or inside vehicles (n = 8). Fractures were the most common acute injuries (n = 16), while other injuries included rhabdomyolysis, compartment syndrome and degloving. Fluid resuscitation was required in 17 patients. 58 surgeries were performed on 18 patients, with wound debridement and amputations being common. Complications such as acute kidney injury, hyperkalaemia, and sepsis were noted during hospitalisation. Individuals with injuries to the leg or thigh experienced a greater burden of injury and incidence of in-hospital complications compared to those with isolated injuries to the foot.

Conclusion

Crush injuries in the non-disaster setting show distinct mechanisms and injury patterns. Those with crush injuries to the leg or thigh more closely resemble a patient cohort seen in the disaster setting compared to those with isolated foot injuries.
Metric star discrepancy results for alternating geometric progressions
Authors: Fukuyama Katusi
Published: December 2024

We determine the limsup value of the law of the iterated logarithm for star discrepancies of alternating geometric progressions with ratios less than

$$-13/3$$

-
13
/
3

.
Electroanalytical overview: the use of sonoelectroanalysis
Authors: Crapnell Robert D. , Bernalte Elena , Ji Xiaobo , Banks Craig E.
Published: December 2024

The synergy of power ultrasound (20–100 kHz) with electrochemistry provides a powerful approach, termed “sonoelectrochemistry”. A useful method that overcomes the use of classical laboratory–based analytical instrumentation is the association of power ultrasound with electroanalytical chemistry, termed “sonoelectroanalysis”. In this overview, we explore the use of sonoelectroanalysis which builds upon Professor Frank Marken’s endeavours with Professor Richard G. Compton. We focus upon fundamental sonoelectrochemical approaches before reviewing the use of sonoelectroanalysis and its enhanced sensitivity and selectivity towards analytes, with an emphasis upon its use within difficult real-world media.
Technical specification envelope for SiC semiconductors to enable high-power in space
Authors: Arrizabalaga Antxon , Álvarez Gustavo
Published: December 2024

High-power electrical systems are needed for the next space missions and the current space qualified silicon semiconductor technology is unable to provide the necessary technical figures to develop them. Following the trend on terrestrial industry, and due to the better physical characteristics when compared to silicon, the silicon carbide semiconductors are considered for their application in space, to address the challenge brought by the high-power. In close collaboration with the European space power industry, the technical characteristics of the new required semiconductors are gathered, classified, and presented in this work. First, the high-power applications mentioned by the industry and the innovation required in each one are presented. Next, the technical characteristics of the required semiconductors for each application and innovation are shown, generating a specific value envelope, starting with the voltage and current ratings, following with the conduction and switching characteristics, and finishing with the thermal requirements and the preferred packaging. Finally, other requirements such as driving components and knowledge generation and transfer are also addressed as requested by industry. This work is a connection between the space power industry and silicon carbide manufacturers, providing them a guide to shape the development of their next products and opening a new business case in space. By giving answer to the needs of the space power industry, this project provides ways for an early and successful adoption of the silicon carbide technology by the European space power industry, giving them an edge advantage over their competitors.
Representation in Engineering-Focused Children’s Literature: A Critical Content Analysis
Authors: Eckhoff Angela
Published: December 2024

Children’s picturebooks have long been understood as a powerful medium for exploring aspects of children’s lives, experiences, and identities serving as mirrors which allow children to see themselves reflected, as windows through which they can gain insight into the experiences of others, and as sliding glass doors when children are connected to the story and characters in meaningful ways. Utilizing a critical content analytic approach, this research examined the identity markers and engineering practices found in contemporary children’s picturebooks with an engineering focus. The analysis yielded key themes that highlight the ways children can interact and connect to the characters and engineering content through both visual imagery and storyline. As the reviewed books held limited social, cultural, and personal identity representations, study findings hold implications for early childhood educators as they highlight the importance of affirming and connecting engineering and design work to the diverse, multifaceted identities of the students in their classrooms. Recommendations from this research call for extending traditional classroom building and construction experiences through the inclusion of engineering-focused children’s literature to enhance and extend children’s understandings of design and engineering work.
Vertebral osteomyelitis in patients with an underlying malignancy or chronic kidney disease – who is at higher risk for adverse outcome?
Authors: Jochimsen Dorothee , Yagdiran Ayla , Meyer-Schwickerath Charlotte , Sircar Krishnan , Kernich Nikolaus , Eysel Peer , Weber Carolyn , Jung Norma
Published: December 2024

Purpose

Patients with vertebral osteomyelitis (VO) and comorbidities, notably chronic kidney disease (CKD), are at risk of early mortality. The aim of this study was to compare characteristics and outcomes of VO patients with an underlying malignancy (ONCO) to VO patients with CKD and VO patients without comorbidities (CONTROL).

Methods

We performed a retrospective analysis of data which was prospectively collected between 2008 and 2020. Primary outcome was treatment failure defined as death and/or recurrence of VO within one year.

Results

241 VO patients (ONCO = 56; CKD = 47; CONTROL = 138) were analysed. Treatment failure occurred in 26% of ONCO and 45% of CKD patients. Staphylococcus aureus was the most common causative pathogen in the CKD (57%) and CONTROL group (43%). ONCO patients showed a broader distribution of common VO-causing pathogens, with coagulase-negative staphylococci (CoNS) accounting for the highest proportion of causative bacteria (27%). Nevertheless, S.aureus was associated with a significantly higher risk of treatment failure in VO ONCO patients.

Conclusion

Treatment failure in VO CKD patients was twice as high as in VO ONCO patients. However, both groups showed high treatment failure rates. CoNS should be considered when starting empirical antibiotic treatment in VO ONCO patients. Moreover, oncological patients with VO caused by S.aureus should be monitored closely.
Rank-one systems, flexible classes and Shannon orbit equivalence
Authors: CORREIA CORENTIN
Published: December 2024

We build a Shannon orbit equivalence between the universal odometer and a variety of rank-one systems. This is done in a unified manner using what we call flexible classes of rank-one transformations. Our main result is that every flexible class contains an element which is Shannon orbit equivalent to the universal odometer. Since a typical example of flexible class is

$\{T\}$

when T is an odometer, our work generalizes a recent result by Kerr and Li, stating that every odometer is Shannon orbit equivalent to the universal odometer. When the flexible class is a singleton, the rank-one transformation given by the main result is explicit. This applies to odometers and Chacon’s map. We also prove that strongly mixing systems, systems with a given eigenvalue, or irrational rotations whose angle belongs to any fixed non-empty open subset of the real line form flexible classes. In particular, strong mixing, rationality or irrationality of the eigenvalues are not preserved under Shannon orbit equivalence.
Education and outreach activities by the Antarctic Treaty Parties: topics and target audiences
Authors: Xavier José C. , Mateev Dragomir , Wilmotte Annick , Peña-Aguirre Andrea , Jupe Julie , Ramos-García Sonia , Abreu José , Alfonso Juan A. , Badhe Renuka , Beck Inga , Bialik Robert J. , Carvalho Andreia , Cotta Mihaela , Choquet Anne , Dotta Sílvia , Fioretti Anna M. , Fikizolo Lisolomzi , Grabow Johanna , Griffin Eoghan , Guímaro Hugo R. , Fialho Patricia , Fragão Joana , Huffman Louise T. , Jung Chaerin , Nath Chandrika , Ozsoy Burcu , de Pomereu Jean , Queirós José P. , Seco José , Shin Hyoung Chul , Topârceanu Florica , Vijayaraghavan Ramcharan , Espírito-Santo Marta , Sparrow Mike , Tiwari Anoop K. , Weeks Sophie , Hughes Kevin A.
Published: December 2024

The relevance of education and outreach (E&O) activities about the Antarctic Treaty has been recognized at the Antarctic Treaty Consultative Meetings (ATCM) and at the Committee for Environmental Protection (CEP). This study examines the key topics and the target audiences detailed in papers submitted to the ATCM on E&O. Since the Antarctic Treaty entered into force in 1961, a total of 216 ATCM papers on E&O have been produced. The number of papers has increased substantially since the mid-1990s. ‘Science’ (76.9%) and ‘Wildlife/Biodiversity/Environment’ (75.5%) were the most addressed topics in these papers, while the ‘Public’ (81.0%) and those attending ‘Schools’ (69.0%) are the main target audiences. ‘Science’ in ATCM papers increased ~120-fold from 1961–1997 to 2015–2023, while ATCM papers discussing engagement with the ‘Public’ increased ~40-fold during the same period. ‘Climate change’ was first mentioned in 2006, and the number of papers per year increased fourfold by 2015–2023. This study shows the increasing interest in E&O through time, addressing key topics to relevant audiences related to the Antarctic region. From an educational perspective, attention should be paid to emerging topics (e.g. equity, diversity and inclusion), and the engagement of early-career professionals and educators should be made a priority.
Predicting mire distribution using species distribution models: a case study of the sub-Antarctic Prince Edward Islands
Authors: Sadiki Maleho M. , Greve Michelle , Hansen Christel D.
Published: December 2024

Peatlands, covering approximately one-third of global wetlands, provide various ecological functions but are highly vulnerable to climate change, with their changes in space and time requiring monitoring. The sub-Antarctic Prince Edward Islands (PEIs) are a key conservation area for South Africa, as well as for the preservation of terrestrial ecosystems in the region. Peatlands (mires) found here are threatened by climate change, yet their distribution factors are poorly understood. This study attempted to predict mire distribution on the PEIs using species distribution models (SDMs) employing multiple regression-based and machine-learning models. The random forest model performed best. Key influencing factors were the Normalized Difference Water Index and slope, with low annual mean temperature, with low annual mean temperature, precipitation seasonality and distance from the coast being less influential. Despite moderate predictive ability, the model could only identify general areas of mires, not specific ones. Therefore, this study showed limited support for the use of SDMs in predicting mire distributions on the sub-Antarctic PEIs. It is recommended to refine the criteria used to select environmental factors and enhance the geospatial resolution of the data to improve the predictive accuracy of the models.
Resonance and stellar dynamos
Authors: Sokoloff D. , Yushkov E. , Serenkova A.
Published: December 2024

Planetary influence on a stellar convective shell can result in a periodic modulation of stellar dynamo drivers. Similar modulation can arise in stellar binary systems. Using the Parker low-mode dynamo model we investigate the properties of nonlinear parametric resonance. This model is a system of four ordinary differential equations and, in the first approximation, describes the processes of generation and oscillation of large-scale magnetic fields in stellar systems. In the absence of nonlinear suppression effects, the problem, by analogy with a system of harmonic oscillations, allows an asymptotic selection of multiple resonant frequencies. Despite the fact that at first glance at these frequencies it is reasonable to expect an increase in the amplitude, the behavior of the system can be just the opposite. All this stuff deserves a systematic analysis of swing excitation in the dynamo sistems in comparison with classical swing excitation in the framework of the Mathieu equation.
Characterizing Solar Spicules and their Role in Solar Wind Production using Machine Learning and the Hough Transform
Authors: Sadeghi R. , Tavabi E.
Published: December 2024

Solar winds originate from the Sun and can be classified as fast or slow. Fast solar winds come from coronal holes at the solar poles, while slow solar winds may originate from the equatorial region or streamers. Spicules are jet-like structures observed in the Sun’s chromosphere and transition region. Some spicules exhibit rotating motion, potentially indicating vorticity and Alfvén waves. Machine learning and the Hough algorithm were used to analyze over 3000 frames of the Sun, identifying spicules and their characteristics. The study found that rotating spicules, accounting for 21% at the poles and 4% at the equator, play a role in energy transfer to the upper solar atmosphere. The observations suggest connections between spicules, mini-loops, magnetic reconnection, and the acceleration of fast solar winds. Understanding these small-scale structures is crucial for comprehending the origin and heating of the fast solar wind.
Features of the solar minimum 24/25 in the evolution of polar and non-polar coronal holes
Authors: Andreeva Olga
Published: December 2024

We present a study of the evolution of two types of coronal holes (CHs) in the solar minimum of 24/25, which was preceded by a prolonged minimum of 23/24 and a weak 24 solar cycle. The goal of the study is to clarify whether the behavior of CHs during this period is also unusual? The study is based on the material of observations obtained by SDO/AIA/193. The Heliophysics Events Knowledgebase was used to localize the CHs and calculate their areas. Analysis of the evolution of the areas of polar and non-polar CHs in solar minimum 24/25 revealed a number of features. The hemispheric asymmetry is evident both in solar activity indices and in the localization of maxima of polar and non-polar CH areas. The hemispheric area imbalance is minimal for polar CHs and pronounced in the regions of non-polar CHs and sunspots. This is consistent with the general concept of polar CHs as the main source of the Sun’s dipole magnetic field. The areas of polar CHs significantly exceed the areas of non-polar CHs and make a significant contribution to the total area of all CHs in the solar disk. It is concluded that the dynamics of polar and nonpolar CHs suggests that the 24/25 minimum is rather close to earlier minima than to the 23/24 minimum.
Effects of small-scale magnetic fields in the photosphere on surface effects for solar-like stars
Authors: Lin Guifang , Li Yan , Su Jie , Wu Tao , Wang Yuetong
Published: December 2024

Magnetic fields are important physics in stellar evolutionary theory, which seriously affects the stellar structure and evolutionary statues. The small-scale magnetic fields in the photosphere are ubiquitous, and float on the stellar surface, which usually couple with the acoustic waves, affecting the propagation of the acoustic waves. Considering the effect of the magnetic fields in the stellar photosphere on the oscillation frequencies, we calculate the asteroseismology for solar-like star KIC 11295426 and KIC 10963065. We obtain the stellar fundamental parameters, especially the strength of small-scale magnetic fields in the stellar photosphere. We find that the small-scale magnetic fields in the stellar photosphere may obviously improve the agreement between the observations and the theoretical models for two stars. The magnetic strength for KIC 11295426 and KIC 10963065 from asteroseismology are in agreement with the stellar period-activity relation.
Exploring the predictability of the solar cycle from the polar field rise rate: Results from observations and simulations
Authors: Biswas Akash
Published: December 2024

The inherent stochastic and nonlinear nature of the solar dynamo makes the strength of the solar cycles vary in a wide range, making it difficult to predict the strength of an upcoming solar cycle. Recently, our work has shown that by using the observed correlation of the polar field rise rate with the peak of polar field at cycle minimum and amplitude of following cycle, an early prediction can be made. In a follow-up study, we perform SFT simulations to explore the robustness of this correlation against variation of meridional flow speed, and against stochastic fluctuations of BMR tilt properties that give rise to anti-Joy and anti-Hale type anomalous BMRs. The results suggest that the observed correlation is a robust feature of the solar cycle and can be utilized for a reliable prediction of peak strength of a cycle at least 2 to 3 years earlier than the minimum.
The North–South asymmetry of the number and magnetic fluxes of active regions of different magneto-morphological types in cycles 23 and 24
Authors: Zhukova Anastasiya
Published: December 2024

Statistical study of 3047 active regions (ARs) from 1996 to 2021 was performed using the catalog of the magneto-morphological classes (MMC) of ARs CrAO. According to the magneto-morphological classification of ARs proposed earlier, all ARs, except for unipolar spots, were sorted out between two categories: regular (bipolar groups obeying the Hale’s polarity law, the Joy’s law, etc.) and irregular ARs (all the rest). We analyzed the number and fluxes of ARs depending on their location in different (relative to the equator) hemispheres. We found that the trends for fluxes are more pronounced. For ARs of both MMC types, they demonstrate signs of both a multi-peak and double-peak structure. Some peaks coincide with the main maxima of the cycle. The second main maximum is mainly formed by the irregular ARs in the S-hemisphere. This might be due to the interaction of the dipole and quadrupole components of the global magnetic field.
Differential Rotation of the Solar Chromosphere using multidecadal Ca ii K Spectroheliograms
Authors: Mishra Dibya Kirti , Routh Srinjana , Jha Bibhuti Kumar , Chatterjee Subhamoy , Banerjee Dipankar
Published: December 2024

The study of the differential rotation in the chromosphere of the Sun is of significant importance as it provides valuable insights into the rotational behaviour of the solar atmosphere at higher altitudes and the coupling mechanism between the various layers of the solar atmosphere. In this work, we employed the image correlation technique, explicitly focusing on plages, intending to estimate the chromospheric differential rotation. For this purpose, we have utilized Ca ii K spectroheliograms (1907 – 2007) from the Kodaikanal Solar Observatory (KoSO), recently calibrated with a better technique to ensure accuracy. Our analysis indicates that plages in the chromosphere exhibit faster rotation and a smaller latitudinal gradient when compared to the rotation rate obtained through sunspot tracking. Furthermore, we investigate the temporal analysis of the chromospheric differential rotation parameters across various solar cycles.
Chromospheric activities of pre-main-sequence stars
Authors: Yamashita Mai , Itoh Yoichi , Takagi Yuhei , Oasa Yumiko
Published: December 2024

We investigated chromospheric activities of pre-main-sequence (PMS) stars. First, we studied the Ca II infrared triplet emission lines with Subaru/HDS and other spectroscopic instruments. Most PMS stars have narrow Ca II lines whose intensities are as large as the maximum of the zero-age main-sequence (ZAMS) stars. The chromosphere of PMS stars is suggested to be filled by the Ca II emitting region. Second, we found many faint chromospheric emission lines such as Mg I and Fe I for more than half of the ZAMS stars. Third, we searched the periodic light variation caused by a starspot for the 26 PMS stars. Their TESS light variations and Ca II emission line strengths show the positive correlation, and are located on the extensions of the superflare stars. In summary, PMS stars have very active chromosphere driven by strong dynamo process due to the fast rotation and the long convection timescale.
Rotational shear in the low photosphere of the Sun
Authors: Corbard T. , Faurobert M. , Gelly B. , Douet R. , Laforgue D.
Published: December 2024

We present a new method to measure the rotational height gradient in the solar photosphere. The method is inspired from differential interferometric techniques, we applied it to spectroscopic observations in the FeI 630.15 nm obtained at the solar telescope THEMIS which is equipped with an efficient adaptive optics system. The spectroscopic data was used to obtain images of the granulation at different line cords formed at different heights in the photosphere. Cross-correlation allows us to measure small systematic shifts between similar images. When observations are performed out of the center of the solar disk, the perspective effect gives rise to a radial shift between images formed at different heights. The measurement of this shift provides us with their formation-height difference. At the center of the disk the perspective effect vanishes but we measured a systematic retrograde shift along the east/west direction of the images formed at higher heights. The measured shifts are proportional to the formation height of the images. We interpret these findings as the evidence of a decrease of the rotational velocity with height in the low photosphere of the Sun and we give an estimate of this gradient.
Magnetic activity under tidal influences in the 2+2 hierarchical quadruple system V815 Herculis
Authors: Kövári Zs. , Strassmeier K. G. , Kriskovics L. , Oláh K. , Borkovits T. , Seli B. , Vida K. , Radványi Á.
Published: December 2024

Tidal forces in close binaries and multiple systems that contain magnetically active component are supposed to influence the operation of magnetic dynamo. Through synchronization the tidal effect of a close companion helps maintain fast rotation, thus supporting an efficient dynamo. At the same time, it can also suppress the differential rotation of the convection zone, or even force the formation of active longitudes at certain phases fixed to the orbit. V815 Her is a four-star system consisting of two close binaries orbiting each other, one of which contains an active G-type main-sequence star. Therefore, the system offers an excellent opportunity to investigate the influence of gravitational effects on solar-type magnetic activity using different methods.
Analyzing Magnetic Network and its Variations over Solar Cycles 23, 24 and 25 Based on Magnetic Power Spectra
Authors: Luo Yukun , Jiang Jie , Wang Ruihui
Published: December 2024

The magnetic network is a typical magnetic structure of the quiet Sun. Investigating its cycle dependence is crucial for understanding its evolution. We aim to identify and analyze the spatial scales of the magnetic network within magnetic power spectra derived from high-resolution Solar and Heliospheric Observatory (SOHO)/Michelson Doppler Imager (MDI) and Solar Dynamics Observatory (SDO)/ Helioseismic and Magnetic Imager (HMI) synoptic magnetograms. The data sets cover the entirety of solar cycles 23, 24, and part of cycle 25. We find that the identified magnetic network sizes identified range from 26 Mm to 41 Mm. There seems to be no obvious dependence on the solar cycle, and the sizes are distributed uniformly within the identification range.
A new generation of solar dynamo model and its application to explore the stellar magnetic cycle
Authors: Zhang Zebin
Published: December 2024

In most of the Babcock–Leighton (BL) type solar dynamo models, the toroidal magnetic field is assumed to be generated in the tachocline. However, magnetic activity of fully convective stars and MHD simulations of global stellar convection have recently raised serious doubts about the importance of the tachocline in the generation of the toroidal field. We have developed a BL-type dynamo model operating in the bulk of the convection zone, and are extending this model to solar-type stars. In this study, we aim at exploring how the starspot properties affect the stellar magnetic cycle. Observations show that faster rotating stars tend to have stronger magnetic activity and shorter magnetic cycles. By considering the higher latitudes and larger tilt angles of starspots for faster rotators, our simulations reproduce observations that faster rotating stars have shorter magnetic cycle and stronger activity.
Short and long term spot evolution on EI Eri
Authors: Kriskovics L. , Kövári Zs. , Seli B. , Oláh K. , Vida K. , Henry G. W. , Granzer T. , Görgei A.
Published: December 2024

We investigate flare activity using photometric data obtained with the Transiting Exoplanet Survey Satellite (TESS). Long-term seasonal period analysis was applied on our APT (Automatic Photoelectric Telescopes af Fairborn observatory, Arizona) time series to study changes in the rotational period. We also looked for activity cycle-like changes with short-term Fourier-transform. We also studied the phase and frequency distribution of hand-selected flares on the available TESS data. The MUlti-SIte Continuous Spectroscopy (MUSICOS) campaign was designed in 1998 to achieve high-resolution, multi-wavelength spectroscopic observations from many sites around the globe, which meant that uninterrupted phase coverage of EI Eri became available. We use these data to reconstruct successive surface-temperature maps of the star in order to study the changes of starspots on a very short timescale. We applied our multi-line Doppler imaging code to reconstruct four consecutive Doppler images. These images were also used to measure surface differential rotation with our cross-correlation technique.
A 2D model for the excitation of the linearly stable inertial modes of the Sun by turbulent convection
Authors: Philidet J. , Gizon L.
Published: December 2024

The newly discovered inertial modes in the Sun offer the opportunity to probe the solar convective zone down to the tachocline. While linear analysis predicts the frequencies and eigenfunctions of the modes, it gives no information about their excitation or their amplitudes. We present here a theoretical formalism for the stochastic excitation of the solar inertial modes by turbulent convection. The amplitudes predicted by our model are in complete agreement with observations, thus supporting the assumption that they are stochastically excited. Our work also uncovers a qualitative transition in the shape of the inertial mode spectrum, between m ≲ 5 where the modes are clearly resolved in frequency, and m ≳ 5 where the modes overlap. This complicates the interpretation of the high-m data, and suggests that a model for the whole shape of the power spectrum is necessary to exploit the full seismic potential of solar inertial modes.
Signature of local (turbulent) dynamo on middle and small scales
Authors: Abramenko V. I.
Published: December 2024

The solar dynamo is a physical process of magnetic field generation due to conversion of kinetic energy of plasma flows into magnetic energy. However, in the mean-field dynamo theory, one needs to segregate scales and consider separately large-scale dynamo and small-scale dynamo. The large-scale dynamo produces the large-scale mean field and unavoidable fluctuations of the mean field. Both are cycle-dependent. The small-scale dynamo is supposed to produce only the small-scale field, and this field is cycle-independent. There is no sharp boundary between the intervals of the large-scale and small-scale dynamos. An unavoidable presence of a smooth transition implies that there is a region where the properties of the large-scale global dynamo and fluctuations inherent to small-scale dynamo co-exist on some intermediate scales. Recent achievements in observations of the small-scale dynamo operation on the smallest observable scales and on the intermediate scales of typical active regions are discussed in the review.