bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced Number of Oligodendrocytes in the Cingulum in Schizophrenia: A Design-Based Stereology Study
Authors: Schmitt* Andrea , Ammann Katharina , Vollhardt Alisa , Schneider-Axmann Thomas , Raabe Florian J. , Yakimov Vladislav , Heinsen Helmut , Hof Patrick R. , Falkai Peter , Schmitz Christoph
Published: October 2024

Schizophrenia is a severe mental disorder with a neurodevelopmental origin whose pathophysiological processes are poorly understood. Magnetic resonance imaging studies have shown structural alterations, such as volume loss in the temporal lobe, including the hippocampus and amygdala, thalamus, and frontal and temporal cortex, while other studies have found reduced oligodendrocyte numbers in the hippocampal CA4 subregion and dorsolateral prefrontal cortex. The decreased number of oligodendrocytes in CA4 was reported to be related to cognitive deficits. The hippocampus and other parts of the limbic system are connected to the white matter of the cingulum bundle, but it had remained unknown whether schizophrenia affects the number of oligodendrocytes also in the cingulum. In a post mortem study, we applied a design-based stereological approach to investigate the number and density of oligodendrocytes in gallocyanin-stained serial sections in the cingulum of the left and right hemispheres in 12 brains from male donors with schizophrenia and 11 brains from age- and sex-matched controls without mental illness. In addition, we evaluated whether oligodendrocyte numbers and densities in the cingulum correlated with the corresponding data in the hippocampal CA4 subregion of the same brains. In schizophrenia, both the mean volume of the left cingulum (difference, -12.7%) and the mean total oligodendrocyte number in the left cingulum (difference, -19.9%) were statistically significantly lower than in healthy controls (p = 0.049 and p = 0.037). No correlations were found for covariates (age, post mortem interval, fixation time). The individual oligodendrocyte numbers in the right cingulum correlated with those in the right hippocampal CA4, and the individual oligodendrocyte densities in the left cingulum correlated with that in the left hippocampal CA4. This post mortem study shows, for the first time, a statistically significant reduction in the mean volume of and the mean oligodendrocyte number in the left cingulum of patients with schizophrenia. Our results support findings of a reduction of oligodendrocytes in limbic regions in schizophrenia, reinforcing the hypothesis that deficits in myelination and trophic support of long projecting axons play a role in the functional disconnectivity of the hippocampus and prefrontal cortex in schizophrenia.
Reviewing Clinical Trials and Meta-Analyses to Assess the Efficacy and Safety of Huachansu in Cancer Treatment
Authors: Genbauffe Aline , Soumoy Laura , Lefranc Florence , Journe* Fabrice
Published: October 2024

Traditional Chinese Medicine (TCM), including herbal remedies and animal secretions like HuaChansu, also called Cinobufacini, has gained attention for its therapeutic efficacy in cancer treatment. HuaChansu, extracted from the skin of toads from the genus Bufo, has been used traditionally for various diseases and recently explored for its anti-cancer properties attributed to bufadienolides like bufalin, resibufogenin, and cinobufagin. Clinical studies and meta-analyses have evaluated its efficacy and safety across various cancers. For hepatocellular carcinoma, non-small cell lung cancer, and pancreatic cancer, pilot studies and clinical trials showed HuaChansu's potential for disease stabilization with minimal toxicity. In breast cancer, a meta-analysis suggested that HuaChansu combined with chemotherapy improves response rates and quality of life. Studies on gallbladder and gastric cancers indicated similar benefits, enhancing therapeutic effects and reducing side effects. In lung cancer, HuaChansu improved survival rates and quality of life when combined with chemotherapy, though placebo-controlled trials are needed. For liver cancer, meta-analyses and randomized controlled trials demonstrated improved survival rates and reduced recurrence when HuaChansu was used with transarterial chemoembolization. These findings underscore HuaChansu potential as a complementary cancer treatment, warranting further research to optimize its dosage and administration for enhanced efficacy.
Küresel Açlık Konusunda Yapılan Uluslararası Yayınlara Bibliyometrik Bir Bakış
Authors: Demir Derya
Published: October 2024

Bu çalışmanın amacı, küresel açlık konusuna ilişkin uluslararası yayınlarda konunun ne şekilde irdelendiği, küresel açlık ile ilgili çalışmaların seyri gibi konulara ilişkin bulguların incelenmesidir. Ayrıca küresel açlık konusunda ekonomi alanındaki yapılan uluslararası bilimsel çalışmaları da tespit etmek amaçlanmıştır. Bu çalışma kapsamında yapılan sorgulama ile elde edilen veriler Web of Science (WoS) veri tabanından alınmış, veriler VOSviewer ve Excel kullanılarak farklı merceklerden analiz edilmiştir. 2013-2024 dönemini içeren 490 yayın incelenmiş, en fazla çalışmanın 76 yayın ile Beslenme Diyetetiği alanında, 78 çalışma ile 2022 yılında, 113 çalışma ile ABD’de yapıldığı belirlenmiştir. Yapılan çalışmalarda incelenen temel konuların tarım, iklim değişikliği, yönetim, mikro beslenme, sürdürülebilir kalkınma hedefleri ile yetersiz beslenme olduğu görülmüştür. Analiz edilen 490 yayın içerisinde ekonomi alanında yapılan çalışma sayısı 33 olarak tespit edilmiş, bu çalışmalara ilişkin bibliyometrik analiz ve anahtar kelime analizi tekrar edilerek atıf analizi yapılmıştır. Küresel açlık konusunda ekonomi alanında en fazla sayıda yayın yapan derginin Food Policy olduğu, Sürdürülebilir kalkınma hedeflerinden Sıfır Açlık ile 21 araştırma, Yoksulluğa Hayır hedefi ile 20 araştırma ilişkili olduğu bulunmuştur. Ekonomi alanında yapılan araştırmalar Afrika, yolsuzluk, açlık, yoksulluk, işsizlik, gıda güvenliği ve yetersiz beslenme konularına odaklanmıştır. Bu çalışma, konuya ilişkin literatür gelişiminin ve entelektüel yapının daha iyi anlaşılmasına yardımcı olacak, en üst sıralarda yer alan dergilerdeki küresel açlık ile ilgili bilim insanlarının bilimsel çalışmaları ve kolektif çabaları hakkında bir retrospektif sunmaktadır.
The Effect of Organizational Justice Perception on Ethical Sensitivity in the Health Sector
Authors: Hekim Sümeyye , Kırılmaz Harun
Published: October 2024

Organizational justice is considered the cause of many individual and corporate results. It is also thought to have significant effects on employees. Justice, which is one of the fundamental values of the organization, affects the attitudes and behaviors of the employees. Therefore, while it is necessary for social organizations, it is even more crucial for health institutions. The culture of injustice perceived by nurses not only harms the health institution but also leads to more critical problems. In addition to the necessity of justice, essential health services include uncertain and high-risk situations to protect and support human health has increased the need for ethical sensitivity. In this context, the study aims to reveal the effect of nurses' perceptions of organizational justice on ethical sensitivity levels. The “Organizational Justice Perception Scale” developed by Niehoff & Moorman (1993) and the “Ethical Sensitivity Questionnaire” developed by Lutzen (1994) were used in the research conducted in one public and two private hospitals in Sakarya. Descriptive statistical methods, independent samples t-test, one-way analysis of variance (ANOVA), correlation analysis and regression analysis were used to analyze the data. According to the study's findings, a low-level positive correlation was found between general organizational justice perceptions and ethical sensitivity levels. Among the sub-dimensions of the scales, it was determined that the highest relationship was between the dimensions of fair distribution and orientation. As a result, it is expected that there will be an increase in ethical sensitivity levels depending on the rise in nurses' perceptions of organizational justice.
ТЕХНОЛОГИЯ ИЗГОТОВЛЕНИЯ АССОЦИИРОВАННОЙВАКЦИНЫ ПРОТИВ ПАСТЕРЕЛЛЕЗА И ЛЕПТОСПИРОЗА КРУПНОГО РОГАТОГО СКОТА И ЕГО АКТУАЛЬНОСТЬ НА СЕГОДНЯШНИЙ ДЕНЬ
Authors: Ермагамбетова Светлана , Киркимбаева Жумагуль , Бияшев Биржан , Сарыбаева Динара , Кузембекова Гульнур , Валдовска Анда
Published: October 2024

Использование ассоциированных вакцин позволяет эффективно контролировать инфекционный фон заболеваний крупного рогатого скота. Основное преимущество ассоциированных вакцин заключается в том, что одномоментное введении вакцины может предотвратить развитие сразу нескольких инфекционных болезни, сформировать иммунный ответ против нескольких антигенных нагрузок на организм и уменьшить количество инъекций. В течение всей жизни, животных прививают поэтапно, в несколько подходов и каждый раз подвергая их дополнительному стрессу, которое влияет на общее состоянии организма. В некоторых хозяйствах количество вакцинаций за первый год жизни молодняка доходит до несколькихдесятков раз. При использовании ассоциированных вакцин, например,против пастереллеза и лептоспироза крупного рогатого скота, в первый год жизни телят вакцинируют в возрасте 20 – 30 суток в дозе 2 мл, подкожно, для взрослого поголовья крупного рогатого скота, доза – 5 мл.Ассоциированную вакцину применяют для профилактических прививок телят и коров. Вакцину можно применять с предохранительной целью и вынужденно в неблагополучных по пастереллезу и лептоспирозу и смежных с ними пунктах.Прививают животных с нормальной температурой, не имеющих клинических признаков заболевания.
Harumanis Mango Classification and Grading System Based on Geometric Shape Extraction for Quality Assessment
Authors: Abu Bakar Mohd Nazri , Abdullah Abu Hassan , Abdul Rahim Norasmadi , Yazid Haniza , Ahmad Muhamad Imran , A. Khalid Noor Aldeen , Zakaria Noor Shazliza , Wan Nik Wan Mohd Faizal , Omar Shafie , Man@Sulaiman Shahrul Fazly , Abu Bakar Norlida , Ahmad Khalidah
Published: October 2024

In agricultural research, a fruit's look, which affects its market value, is the first and most crucial sensory evaluation. According to external criteria like shape, size, ripeness index, and flaws or internal criteria like sweetness, flavor, and nutrients, fruits can be categorized and rated. Due to the grading task's importance and difficulty in post-harvest management, there is a high standard for fruit quality that must constantly be met. Growing interest in various categorization and grading algorithms aims to use non-contact and novel measurements to lessen the subjectivity of visual examination. In this paper, the proposed system that uses fruit shape and size as feature parameters for evaluating fruit quality has been implemented. A morphological analysis, median filter, and multilevel threshold-based image processing technique were created to assess the geometric shape of the mango image, including its length, width, and area. These factors are required to compute the standard shape of the Harumanis mango's similarity index and divide its size into four mass grades: small (S), medium (M), large (L), and extra-large (XL). The test results show the suggested technique had an accuracy rate of 98% and 96% for grading the size based on mass estimation and was very successful for quality classification based on measurement of the similarity index for a standard shape.
Systematic Review of Recent Chest Radiograph Bone Suppression Techniques
Authors: Hassan Muhammad Amri , Abdul Rahman Norazeani , Mohd Shapri Ahmad Husni , Che Ismail Rizalafande
Published: October 2024

Chest radiograph (CXR) are essential diagnostic tools to visualize the thoracic cavity's anatomical structures, particularly the lungs. However, the interpretability of these radiographs can be compromised by the presence of overlying bones, such as the ribs and clavicles, which may obstruct the view of the lung regions. Recently, the bone suppression technique applied to CXR has shown promise in aiding radiologists and computer-aided diagnosis systems in detecting lung diseases. Numerous studies have indicated that employing bone-suppressed images (BSIs) provides clinical evidence of enhancing diagnostic accuracy and confidence. This systematic review paper provides a recent of CXR bone suppression techniques and highlights their respective results. The preference for systematic analysis over traditional literature review stems from its capability to mitigate research bias. Recently, researchers increasingly favour using deep learning methodology to suppress bone structures. Implementing these techniques opens a pathway for various applications, particularly in lung nodule detection or pathology assessment through radiological analysis of CXR.
Sizing of Grid-Connected Photovoltaic System with Roof Space Constraint
Authors: Teh Kai Jun , Ng Khai Le , Nordin Nur Dalilah , Leong Kah Meng , Chan Bun Seng , Mazlam Noor Fatihah , Mohd Suhaimi Shaffika , Yunianta Arda , Ahmed Malik Sameen
Published: October 2024

The installation of building-integrated photovoltaic systems has increased over the past years. This paper presents the sizing method of photovoltaic systems with rooftop space as a constraint. A sizing tool is developed to assist the design of PV systems with roof space constraints by using Visual Basic for Application. This new sizing tool is developed by implementing an iterative technique and is able to optimize the quantity of PV panels while overcoming the problem of space constraints on the rooftop. A roof dimension from Google Maps is used for the case study. This tool minimizes the design process time for an integrated PV system with minimum information on a rooftop.
Greening of Automated Hydroponic System Based on IoT and Enhanced Solar Energy with Electricity Saving Box
Authors: Wong Adam Yoon Khang , Ya’akub Abdul Rauf , Mohamat Gani Johar Akbar , Awang Teh Azman , Kovtun Viacheslav , Pusppanathan Jaysuman , Jamil Alsayaydeh Jamil Abedalrahim
Published: October 2024

In recent years, advancements in technology have reshaped the landscape of agricultural practices, aiming to address the challenges posed by conventional farming methods such as traditional hydroponic system. Traditional hydroponic systems often rely on conventional energy sources, leading to elevated energy consumption and carbon emissions. Addressing these challenges, the primary objective of this study is to design, implement, and evaluate an integrated hydroponic system that leverages IoT-based real-time monitoring and control, optimized solar energy utilization, and an electricity-saving box. IoT-enabled sensors and actuators monitor key parameters, facilitating automated adjustments to nutrient delivery, temperature, and humidity. Enhanced solar energy capture is achieved through advanced photovoltaic technologies, while the electricity-saving box ensures efficient power management. The findings demonstrate a substantial reduction in energy consumption compared to traditional hydroponic systems. The integrated approach contributes to minimized carbon emissions and resource utilization, aligning with eco-friendly cultivation practices. Real-time monitoring and control capabilities empower growers to optimize cultivation conditions for enhanced plant health and growth. In conclusion, this research underscores the potential of merging IoT technology, enhanced solar energy, and an electricity-saving box to transition hydroponic systems into sustainable and environmentally responsible platforms with the 35% of system efficiency enhancement achieved through the proposed method bring about transformative implications for automated hydroponic systems
Navigating Traffic: A Survey of Techniques and Challenges in Congestion Detection
Authors: Uttraphan Chessda , Chua Wee Heng , Chew Chang Choon , Ahmad Nabihah , Edwin Raj A Arul
Published: October 2024

Traffic congestion is a pervasive problem in urban areas due to the increasing number of people owning vehicles each year. The consequences of congestion include air pollution, increased fuel consumption, and wasted time and money. Therefore, traffic congestion detection is vital for effectively monitoring and managing traffic flow. Moreover, congestion detection can aid in the development of several applications, including Intelligent Transportation Systems (ITS), traffic management, emergency services, and environmental management. Researchers have utilized various approaches in the past to alleviate or resolve congestion. This paper highlights several recently proposed techniques for detecting traffic congestion. Additionally, it discusses five potential challenges that may arise for further improvement in the future: traffic features, congestion levels, traffic scene factors, real-time detection, and location scalability.
Dynamic Model Design and Controller Development of Lower Limb Prosthesis Through Matlab Simscape Multibody Toolbox
Authors: Nemah Mohammed Najeh , H. Abada Hashim
Published: October 2024

Indeed, humans have achieved remarkable feats. Even so, some people lose parts of their bodies due to accidents, disease, or any other reason. Among them, lower limb amputation is the worst. Thus, prosthesis provides an appropriate solution to assist amputees in reintegration into society. Unfortunately, the user of several prostheses feels like a robot when using the prostheses with a traditional controller. Therefore, several efforts have been made to convey the amputee's brain instructions to the prosthesis using electromyography (EMG) sensors attached to the patient's residual muscles. This study aims to derive and realize the model of the lower limb prosthesis using the MATLAB Simscape Multibody library. The simulation model has been created by importing the essential structure from the CAD software. The model simulates the above-knee prosthesis with a single degree of freedom by allowing the knee joint to revolute voluntarily to create flexion and extension movements. A wireless EMG circuit board has been designed and evaluated to collect the amputee's residual muscle electricity. Subsequently, a novel combination between the traditional PID and Adaptive Neuro Fuzzy Inference System (ANFIS) controllers is designed to control, with a high percent of stability, the simulated prosthesis and overcome the oscillation of EMG signals. The movement of the simulated lower limb prosthesis is calibrated to the healthy leg of an 11-year-old child. The evaluation experimental tests have been accomplished by involving a healthy participant to compare his normal leg with the simulated controllable robotic prosthesis. The experimental results proved the functionality of the designed model to track the movement of the healthy lower limb. In addition, the effectiveness of the suggested controller to manipulate the prosthesis knee joint is proven. Fabricating the designed lower limb prosthetic and integrating it with the combination controllers proposed in this work is a continuation of this study in the future.
Stress Detection Through Text in Social Media Using Machine Learning Techniques
Authors: Kasmin Fauziah
Published: October 2024

In today's digital era, the prevalence of stress-related discussions on social media platforms such as Twitter, Facebook, Instagram, and Reddit has garnered considerable attention. Human stress causes mental and financial problems, impairs one's ability to think clearly at work, strains relationships with co-workers, depresses oneself, and, in extreme circumstances, can result in suicide. Therefore, identifying stress is crucial to reducing its effects. Stress detection and measurement in the large world of social media data is a difficult and time-consuming task. Hence, this comprehensive review explores the crucial realm of detecting and quantifying stress through user behaviour analysis, leveraging the capabilities of machine learning approach. Our primary goals encompass developing a binary stress detection model, conducting a thorough comparative analysis of machine learning models, and designing an intuitive stress detection dashboard for visualizing data. The study utilizes three distinct datasets: the Reddit dataset containing 3,532 records, the Twitter dataset with 1,228 records, and an integrated dataset combining data from both sources, total 4,760 records. Key techniques for feature extraction, particularly Term Frequency-Inverse Document Frequency (TF-IDF), are employed to extract valuable insights from textual data. The study's findings demonstrate how well some machine learning models perform with various datasets and training/testing splits. Interestingly, the Logistic Regression model performs admirably, with an astounding 73% accuracy on the Reddit dataset. All models perform well on the Twitter dataset, however under certain conditions, the Support Vector Machine model outperforms the others with an amazing 81% accuracy. With an accuracy rating of 74% in the combined dataset, the Support Vector Machine likewise shows up as the best performer. The findings contribute significantly to ongoing efforts in enhancing stress detection, early intervention strategies, and health research within the sphere of social media.
The global approaches to the regulation of quantum communication
Authors: Kuleshov D. A.
Published: October 2024

In the rapidly evolving field of quantum communication, the regulatory framework plays a crucial role in ensuring security, standardization, and international cooperation. This article examines various approaches employed by countries to regulate quantum communication. The purpose of this research is to comprehensively analyze and compare different international approaches to the regulation of quantum communication to identify key features characteristic of the current stage of development and regulation of quantum communication, as well as to develop recommendations for optimizing and improving regulatory governance in this area. The methodological basis of the study consisted of general scientific and special methods. A detailed study of various legal documents, strategies, and standards related to quantum communication was conducted using the following general scientific methods: analysis, synthesis, induction, and system analysis. Among the special legal methods used was the comparative legal method, which made it possible to identify general trends, differences, and unique approaches in the regulation of quantum communication, as well as the formal-legal method for studying legal categories and legislative techniques used in various acts in the studied area. The study systematically examines legislative measures, government policies, and industry standards to determine the relationship between technological innovation and regulatory governance in the field of quantum communication. The research revealed that the regulation of quantum communication is primarily carried out at the level of strategic documents, such as national roadmaps, which contain recommendations and guidelines for regulating quantum communication. It was found that technical standards play a vital role in the development of quantum communication, with this development occurring at both national and international levels. Special groups and centers have been established for the effective implementation, development, and regulation of quantum communication, which allows for the identification of social, legal, political, and ethical issues. The main conclusions include the need to monitor administrative barriers, identify priority sectors for the implementation of quantum communication, and recognize quantum communication as a dual-use technology. It is recommended that an international certification and tracking system be created for quantum communication devices for export and import control purposes.
Dialektische Methode
Authors: Ohrt Connor
Published: October 2024

Die dialektische Methode (DM) wird in der Antike noch als eine Gesprächsmethode verstanden, bei der die Gesprächsteilnehmer durch Äußerungen gegensätzlicher Meinungen zu einer höheren Form der Erkenntnis
gelangen. Seit der Aufk lärung jedoch ist die DM ein Verfahren zur Aufdeckung von Gegensätzen innerhalb eines Gegenstandes oder Sachverhaltes; diese Aufdeckung mündet bei der DM der Kritischen Theorie
in der Kritik an dem Untersuchungsgegenstand, insofern er sich in seine eigenen Widersprüche verstrickt.
Dialogischer Sprachaufbau
Authors: Jelonnek Stefan J.
Published: October 2024

Der dialogische Sprachaufb au umfasst im Methodischen Konstruktivismus die Forderung, dass jeder Schritt bei der expliziten Entwicklung einer wissenschaftlichen Terminologie in einer Lehr-
und Lernsituation zwischen ‚Du‘ und ‚Ich‘ zur Verfügung gestellt wird.
How do lifecycle, employment and childcare support contribute to the gender pension gap in Europe? The clustering methods analysis
Authors: Jędrzychowska Anna , Kwiecień Ilona , Poprawska Ewa , Cichowicz Ewa , Gałecka-Burdziak Ewa
Published: October 2024

Despite ongoing efforts in Europe to tackle discrimination against women in the labor market and societal roles, gender inequality remains entrenched. This study shifts focus from the design of pension systems to explore other key factors impacting women’s careers. By examining life cycle demographics, career paths, and childcare support systems, we utilize clustering to categorize European countries based on factors influencing women’s pension capital accumulation, excluding pension design. Our innovative approach highlights the significance of these factors in the gender pension gap. Findings suggest demographic and social similarities across countries do not necessarily equate to equitable retirement scenarios for women compared to men, underscoring the potential of pension system design to mitigate disparities. Using Ward’s method and the silhouette index for country classification on 10 variables, our analysis reveals distinct differences in gender pension gaps across Southern, Northern, Western, and Eastern Europe. This divergence, alongside observed differences in retirement outcomes for women affected by prior pension regulations, points to increasing challenges for younger European women in achieving pension parity with past generations.
J-PLUS: Beyond Spectroscopy. III. Stellar Parameters and Elemental-abundance Ratios for Five Million Stars from DR3
Authors: Huang 黄 Yang 样 , Beers Timothy C. , Xiao 肖 Kai 凯 , Yuan 苑 Haibo 海波 , Lee Young Sun , Gu 顾 Hongrui 弘睿 , Hong Jihye , Liu 刘 Jifeng 继峰 , Fan 范 Zhou 舟 , Coelho Paula , Cruz Patricia , Galindo-Guil F. J. , Daflon Simone , Jiménez-Esteban Fran , Cenarro Javier , Cristóbal-Hornillos David , Hernández-Monteagudo Carlos , López-Sanjuan Carlos , Marín-Franch Antonio , Moles Mariano , Varela Jesús , Vázquez Ramió Héctor , Alcaniz Jailson , Dupke Renato , Ederoclite Alessandro , Sodré Laerte , Angulo Raul E.
Published: October 2024

We present a catalog of stellar parameters (effective temperature T
eff, surface gravity

log
g

, age, and metallicity [Fe/H]) and elemental-abundance ratios ([C/Fe], [Mg/Fe], and [α/Fe]) for some five million stars (4.5 million dwarfs and 0.5 million giant stars) in the Milky Way, based on stellar colors from the Javalambre Photometric Local Universe Survey (J-PLUS) DR3 and Gaia EDR3. These estimates are obtained through the construction of a large spectroscopic training set with parameters and abundances adjusted to uniform scales, and trained with a kernel principal component analysis. Owing to the seven narrow/medium-band filters employed by J-PLUS, we obtain precisions in the abundance estimates that are as good as or better than those derived from medium-resolution spectroscopy for stars covering a wide range of the parameter space: 0.10–0.20 dex for [Fe/H] and [C/Fe], and 0.05 dex for [Mg/Fe] and [α/Fe]. Moreover, systematic errors due to the influence of molecular carbon bands on previous photometric-metallicity estimates (which only included two narrow/medium-band blue filters) have now been removed, resulting in photometric-metallicity estimates down to [Fe/H] ∼ −4.0, with typical uncertainties of 0.40 dex and 0.25 dex for dwarfs and giants, respectively. This large photometric sample should prove useful for the exploration of the assembly and chemical-evolution history of our Galaxy.
A Timeline of the M81 Group: Properties of the Extended Structures of M82 and NGC 3077
Authors: Velguth Benjamin N. , Bell Eric F. , Smercina Adam , Price Paul , Gozman Katya , Monachesi Antonela , D’Souza Richard , Bailin Jeremy , de Jong Roelof S. , Jang In Sung , Slater Colin T.
Published: October 2024

Mergers of and interactions between galaxies imprint a wide diversity of morphological, dynamical, and chemical characteristics in stellar halos and tidal streams. Measuring these characteristics elucidates aspects of the progenitors of the galaxies we observe today. The M81 group is the perfect galaxy group to understand the past, present, and future of a group of galaxies in the process of merging. Here, we measure the end of star formation (t
90) and metallicity ([M/H]) of the stellar halo of M82 and the eastern tidal stream of NGC 3077 to: (1) test the idea that M82 possesses a genuine stellar halo, formed before any interaction with M81; (2) determine if NGC 3077's tidal disruption is related to the star formation history in its tails; and (3) create a timeline of the assembly history of the central trio in the M81 group. We argue that M82 possesses a genuine, metal-poor ([M/H] ∼ −1.62 dex) stellar halo, formed from the merger of a small satellite galaxy roughly 6.6 Gyr ago. We also find that the stars present in NGC 3077's tails formed before tidal disruption with M81, and possess a roughly uniform metallicity as shown in S. Okamoto et al., implying that NGC 3077's progenitor had significant population gradients. Finally, we present a timeline of the central trio’s merger/interaction history.
Precise and Accurate Short-term Forecasting of Solar Energetic Particle Events with Multivariate Time-series Classifiers
Authors: Rotti Sumanth A. , Aydin Berkay , Martens Petrus C.
Published: October 2024

Solar energetic particle (SEP) events are one of the most crucial aspects of space weather that require continuous monitoring and forecasting using robust methods. We demonstrate a proof of concept of using a data-driven supervised classification framework on a multivariate time-series data set covering solar cycles 22, 23, and 24. We implement ensemble modeling that merges the results from three proton channels (E ≥ 10 MeV, 50 MeV, and 100 MeV) and the long-band X-ray flux (1–8 Å) channel from the Geostationary Operational Environmental Satellite missions. Our task is binary classification, such that the aim of the model is to distinguish strong SEP events from nonevents. Here, strong SEP events are those crossing the Space Weather Prediction Center’s “S1” threshold of solar radiation storm and proton fluxes below that threshold are weak SEP events. In addition, we consider periods of nonoccurrence of SEPs following a flare with magnitudes ≥C6.0 to maintain a natural imbalance of sample distribution. In our data set, there are 244 strong SEP events comprising the positive class. There are 189 weak events and 2460 “SEP-quiet” periods for the negative class. We experiment with summary statistic, one-nearest neighbor, and supervised time-series forest (STSF) classifiers and compare their performance to validate our methods for prediction windows from 5 minutes up to 60 minutes. We find the STSF model to perform better under all circumstances. For an optimal classification threshold of ≈0.3 and a 60 minutes prediction window, we obtain a true skill statistic TSS = 0.850, Heidke skill score HSS = 0.878, and Gilbert skill score GSS = 0.783.
Measuring Dwarf Galaxy Intrinsic Abundance Scatter with Mid-resolution Spectroscopic Surveys: Calibrating APOGEE Abundance Errors
Authors: Mead Jennifer , Ness Melissa , Andersson Eric , Griffith Emily J. , Horta Danny
Published: October 2024

The first generations of stars left their chemical fingerprints on metal-poor stars in the Milky Way and its surrounding dwarf galaxies. While instantaneous and homogeneous enrichment implies that groups of conatal stars should have the same element abundances, small amplitudes of abundance scatter are seen at fixed [Fe/H]. Measurements of intrinsic abundance scatter have been made with small high-resolution spectroscopic data sets where measurement uncertainty is small compared to this scatter. In this work, we present a method to use mid-resolution survey data, which have larger errors, to make this measurement. Using APOGEE Data Release 17, we calculate the intrinsic scatter of Al, O, Mg, Si, Ti, Ni, and Mn relative to Fe for 333 metal-poor stars across six classical dwarf galaxies around the Milky Way, and 1604 stars across 19 globular clusters (GCs). We calibrate the reported abundance errors in bins of signal-to-noise ratio and [Fe/H] using a high-fidelity halo data set. Applying these calibrated errors to the APOGEE data, we find small amplitudes of average intrinsic abundance scatter in dwarf galaxies ranging from 0.03 to 0.09 dex, with a median value of 0.047 dex. For the GCs, we find intrinsic scatters ranging from 0.01 to 0.11 dex, with particularly high scatter for Al and O. Our measurements of intrinsic abundance scatter place important upper bounds, which are limited by our calibration, on the intrinsic scatter in these systems, as well as constraints on their underlying star formation history and mixing that we can look to simulations to interpret.
Balmer Decrement Anomalies in Galaxies at z ∼ 6 Found by JWST Observations: Density-bounded Nebulae or Excited H i Clouds?
Authors: Yanagisawa Hiroto , Ouchi Masami , Nakajima Kimihiko , Yajima Hidenobu , Umeda Hiroya , Baba Shunsuke , Nakagawa Takao , Nakane Minami , Matsumoto Akinori , Ono Yoshiaki , Harikane Yuichi , Isobe Yuki , Xu Yi , Zhang Yechi
Published: October 2024

We investigate the physical origins of the Balmer decrement anomalies in GS-NDG-9422 and RXCJ2248-ID galaxies at z ∼ 6 whose Hα/Hβ values are significantly smaller than 2.7, the latter of which also shows anomalous Hγ/Hβ and Hδ/Hβ values beyond the errors. Because the anomalous Balmer decrements are not reproduced under the Case B recombination, we explore the nebulae with optical depths smaller and larger than the Case B recombination by physical modeling. We find two cases quantitatively explaining the anomalies: (1) density-bounded nebulae that are opaque only up to around Lyγ–Ly8 transitions and (2) ionization-bounded nebulae partly/fully surrounded by optically thick excited H i clouds. The case of (1) produces more Hβ photons via Lyγ absorption in the nebulae, requiring fine tuning in optical depth values, while this case helps ionizing photon escape for cosmic reionization. The case of (2) needs the optically thick excited Hi clouds with N
2 ≃ 1012−1013 cm−2, where N
2 is the column density of the hydrogen atom with the principal quantum number of n = 2. Interestingly, the high N
2 values qualitatively agree with the recent claims for GS-NDG-9422 with the strong nebular continuum requiring a number of 2s-state electrons and for RXCJ2248-ID with the dense ionized regions likely coexisting with the optically thick clouds. While the physical origin of the optically thick excited H i clouds is unclear, these results may suggest gas clouds with excessive collisional excitation caused by an amount of accretion and supernovae in the high-z galaxies.
An Analytic Characterization of the Limb Asymmetry—Transit Time Degeneracy
Authors: Murphy Matthew M. , Beatty Thomas G. , Apai Dániel
Published: October 2024

Atmospheres are not spatially homogeneous. This is particularly true for hot, tidally locked exoplanets with large day-to-night temperature variations, which can yield significant differences between the morning and evening terminators—known as limb asymmetry. Current transit observations with the James Webb Space Telescope (JWST) are precise enough to disentangle the separate contributions of these morning and evening limbs to the overall transmission spectrum in certain circumstances. However, the signature of limb asymmetry in a transit light curve is highly degenerate with uncertainty in the planet’s time of conjunction. This raises the question of how precisely transit times must be measured to enable accurate studies of limb asymmetry, in particular with JWST. Although this degeneracy has been discussed in the literature, a general description of it has not been presented. In this work, we show how this degeneracy results from apparent changes in the transit contact times when the planetary disk has asymmetric limb sizes. We derive a general formula relating the magnitude of limb asymmetry to the amount by which it would cause the apparent time of conjunction to vary, which can reach tens of seconds. Comparing our formula to simulated observations, we find that numerical fitting techniques add additional bias to the measured time, of generally less than a second, resulting from the occultation geometry. We also derive an analytical formula for this extra numerical bias. These formulae can be applied to planning new observations or interpreting literature measurements, and we show examples for commonly studied exoplanets.
Effects of Bursty Star Formation on [C ii] Line Intensity Mapping of High-redshift Galaxies
Authors: Liu Lun-Jun , Sun Guochao , Chang Tzu-Ching , Furlanetto Steven R. , Bradford Charles M.
Published: October 2024

Bursty star formation—a key prediction for high-redshift galaxies from cosmological simulations explicitly resolving stellar feedback in the interstellar medium—has recently been observed to prevail among galaxies at redshift z ≳ 6. Line intensity mapping (LIM) of the 158 μm [C ii] line as a star formation rate (SFR) indicator offers unique opportunities to tomographically constrain cosmic star formation at high redshift, in a way complementary to observations of individually detected galaxies. To understand the effects of bursty star formation on [C ii] LIM, which have remained unexplored in previous studies, we present an analytic modeling framework for high-z galaxy formation and [C ii] LIM signals that accounts for bursty star formation histories induced by delayed supernova feedback. We use it to explore and characterize how bursty star formation can impact and thus complicate the interpretation of the [C ii] luminosity function and power spectrum. Our simple analytic model indicates that bursty star formation mainly affects low-mass galaxies by boosting their average SFR and [C ii] luminosity, and in the [C ii] power spectrum it can create a substantial excess in the large-scale clustering term. This distortion results in a power spectrum shape that cannot be explained by invoking a mass-independent logarithmic scatter. We conclude that burstiness must be accounted for when modeling and analyzing [C ii] data sets from the early Universe, and that in the extreme, the signature of burstiness may be detectable with first-generation experiments such as TIME, CONCERTO, and CCAT-DSS.
Anisotropies of 40–139 keV Ions Measured beyond the Termination Shock and in the Very Local Interstellar Medium
Authors: Dialynas Konstantinos , Krimigis Stamatios M. , Decker Robert B. , Hill Matthew E. , Nikoukar Romina , Opher Merav
Published: October 2024

We analyze the count rates of 40–139 keV ions that were measured in situ by the Low Energy Charged Particle instrument on Voyager 1 in order to identify the suprathermal ion anisotropies beyond the termination shock and in the very local interstellar (IS) medium (VLISM). The analysis results in a region of ∼9–10 au before the heliopause (HP) where the radial anisotropy of ions is negative, while the azimuthal ion anisotropy inside the heliosheath lies in the −T direction. In agreement to our previous analyses, we identify a positive radial anisotropy of ions up to at least ∼30 au beyond the HP, which becomes nearly zero from 2021 up to 2023 November (for ∼10 au). Notably, the anisotropy in the azimuthal direction is statistically zero throughout the upstream region, i.e., for ∼40 au past the HP, showing that the 40–139 keV ion anisotropy in the VLISM is only in the radial direction and has no azimuthal component. The presence of suprathermal ions of solar origin over such long spatial scales in the VLISM, along with the inflow of ions from IS space into the heliosheath, are important constraints for characterizing the interaction of the heliosheath with the VLISM. Our observations provide indications that V1 has entered a new regime in the VLISM since (at least) the year 2021, progressively developing characteristics akin to the pristine IS medium. Alternatively, this drop to nearly zero radial anisotropies beyond 2021 could be a manifestation of a prolonged compression/shock of solar origin.
Hot Stars in the GALEX Ultraviolet Sky Surveys (GUVcat_AISxSDSS_HS) and the Binary Fraction of Hot Evolved Stars
Authors: Bianchi Luciana
Published: October 2024

We present a catalog of 71,364 pointlike UV sources with Sloan Digital Sky Survey (SDSS) photometry and GALEX far-UV (FUV)−near-UV (NUV) ≤0.1 mag. The limit corresponds to stellar T
eff ≳15,000−20,000 K, slightly depending on gravity but nearly reddening independent for Milky Way−type dust. Most sources are hot white dwarfs (WDs) and subdwarfs. Comparing the spectral energy distribution (SED; GALEX FUV, NUV, SDSS u,g,r,i,z) of 35,294 sources having good photometry with colors of stellar models and known objects, we identify 12,404 ±

1267

1871

binary hot-compact stars with a cooler, less-evolved companion (with a possible 8%–15% contamination by low-redshift QSOs), and 22,848 ±

3853

1267

single-star candidates. Single-star counts are an upper limit because pairs of similar stars have single-star-like SEDs, and hot WDs with main-sequence companions of certain types (depending on the WD’s radius) are missed or counted as single in the available wavelength range and selection. The catalog offers unique leverage for identifying hot WDs, elusive at longer wavelengths when a cooler, larger companion dominates optical–IR fluxes: 51% of the binary-star and 20% of the single-star candidates are previously unknown objects. Gaia DR3 provides a parallax with error ≤20% for 34% of the binary-star candidates and 45% of single-star candidates, allowing T
eff, E

B−V
, radius, and L
bol to be derived from SED analysis. The binary-candidate sample usefully expands the overall current binary-WD census to subpopulations elusive to Gaia and to other searches. The binary fraction among this specific sample of hot compact objects, albeit with the mentioned biases, b

f
≳ 46%, compared with that of their progenitors (>80%–50% for mass range 8−1M
⊙, according to M. Moe), implies a lower merging rate than found for massive stars by H. Sana et al.
Impacts of Extreme Ultraviolet Late Phase of the Solar Flare on Ionospheric Electrodynamics
Authors: Liu Xuanqing , Liu Jing , Chen Junjie , Qian Liying , Chamberlin Phillip C. , Chen Yao , Kong Xiangliang , Li Shuhan
Published: October 2024

Previous investigations of ionospheric electrodynamical responses to solar flares primarily focused on the main phases (MPs) of solar flares. Typical solar irradiance models for driving global ionosphere models do not include the extreme ultraviolet (EUV) late phase (ELP) of flares, which was recently observed with new high-quality solar EUV spectra. Thus, it is still unclear how ionospheric electrodynamics respond to the flare ELP. Here, we analyzed the ionospheric electrodynamical response to the MP and ELP of the X9.3 flare on 2017 September 6, using observations from ground magnetometers, along with simulation results from an ionosphere–thermosphere coupled model. Observations indicated an intensification of the dayside eastward equatorial electrojet (EEJ) by approximately 12 nT at the ELP peak as compared to the quiet day reference. Additionally, the dayside eastward electric field increased due to the ELP, which is different from the reduction of dayside electric fields during MP. The upward
E
×
B
plasma drifts decreased by 2.5 m s–1 during MP but increased by 0.75 m s–1 during the ELP. Altitude-dependent responses of ionospheric conductivities to the ELP modulated the relative contribution of the E- and F-region wind dynamo to zonal electric fields, resulting in an overall increase in the daytime eastward electric fields. Furthermore, combined effects of electric fields and conductivities enhancements contributed to EEJ intensification during the ELP. This study enhances our understanding of how solar flares with ELP change global ionospheric electric fields and currents.
Length–weight relationships for 14 cypriniform freshwater fish species (Actinopterygii) from the Upper Mississippi River Basin
Authors: Bagley Justin C. , Breitman Maria Florencia
Published: October 2024

Here, we use long-term monitoring data from fisheries surveys across six Mississippi River reaches spanning > 750 river miles (>1200 km) to estimate length–weight relationships (LWRs) for 14 cypriniform fishes native to the Upper Mississippi River system. Relationships between log10-transformed values of fish total weights [g] and total lengths [cm] were analyzed using standard linear modeling and hypothesis-testing approaches. Focal species included four North American minnows in family Leuciscidae [Cyprinella lutrensis (Baird et Girard, 1853), Notropis atherinoides Rafinesque, 1818, Notropis hudsonius (Clinton, 1824), and Paranotropis volucellus (Cope, 1865)] and 10 suckers in the family Catostomidae [Carpiodes carpio (Rafinesque, 1820), Carpiodes cyprinus (Lesueur, 1817), Carpiodes velifer (Rafinesque, 1820), Cycleptus elongatus (Lesueur, 1817), Ictiobus bubalus (Rafinesque, 1818), Ictiobus niger (Rafinesque, 1819), Moxostoma anisurum (Rafinesque, 1820), Moxostoma carinatum (Cope, 1870), Moxostoma erythrurum (Rafinesque, 1818), and Moxostoma macrolepidotum (Lesueur, 1817)]. Congruent with previous studies, estimates of parameter b were consistent with isometric or weakly allometric growth and ranged from 2.834 (P. volucellus) to 3.351 (C. elongatus), while estimates of parameter a ranged from 0.002 (C. elongatus) to 0.014 (C. velifer).
A survey of keys for the identification of newly described insect genera: recommendations for authors, reviewers, editors, and publishers
Authors: Packer Laurence
Published: October 2024

Large numbers of new taxa are described annually and while there is a great need to make them identifiable, there seems little consistency in how this might be facilitated. 427 papers published in 2021 and 2022 were surveyed, which described 587 new insect genera. Only 136 of these papers included keys, and these allowed the identification of 233 of the new genera (31.9% of papers and 39.7% of the new genera). The proportion of papers that included a key varied significantly among insect orders but not among the handful of journals wherein the bulk of the new genera were described. Overall, for 17 key-related variables assessed in a binary fashion (optimal vs suboptimal), the average key had almost six criteria that were scored as being suboptimal. For example, less than one-fifth facilitated retracing and less than 12% had illustrated keys where the images were conveniently located close to the relevant key couplets. Progress towards confirming a putative identification was possible in all papers, through the inclusion of a diagnosis, habitus images, or both.

Based upon this analysis, and expanding on previous suggestions for key construction, 23 recommendations are made on how to make an identification key maximally useful for users and I indicate the relative ease with which each could be adhered to. Identification keys should accompany all new taxon descriptions, guidelines for effective key construction should be added to journals’ instructions to authors, editors and reviewers should check keys carefully, and publishers should be attentive to the needs of users through, for example, permitting duplication of images to make keys easier to use. Recommendations are likely relevant to all levels in the taxonomic hierarchy for all organisms, despite the data being derived from generic-level keys for insects.