bluuebunny/crossref_metadata_2025 huggingface dataset:
Examining the Relationship Between Macroeconomic Indicators and Stock Market Development in Morocco
Authors: - El Yamani Rachida , - Iaataren Idriss
Published: October 2024

The literature is still debating the key macroeconomic variables influencing the stock market development. This paper attempts to provide an empirical study to identify the macroeconomic conditions required for the stock market development in a developing country, in this case, Morocco. The goal is to determine whether macroeconomic variables can improve Moroccan stock market development.

The purpose of this study, which covers the period 1996-2020, is to determine the macroeconomic factors that contribute the Moroccan stock market development. It examines the impact of economic growth, banking sector development, stock market liquidity, foreign direct investment and macroeconomic stability measured by the Barro’s Misery index. The autoregressive distributed lag approach (ARDL) was estimated, to get both the short and long run coefficients of the macroeconomic variables that determine Moroccan stock market development.
The results reveal that stock market liquidity, banking sector development and foreign direct investment effect positively Moroccan’s stock market development, but macroeconomic stability effects it negatively. While the economic growth does not impact it, whether for the short or long run.

There have been no relevant studies that have focused on the macroeconomic determinants of the Moroccan stock market in the short and long terms, despite the fact that theoretical and empirical literature offers diverse perspectives on which factors can determine stock market development.
By examining the macroeconomic variables that contribute to Moroccan stock market development and introducing the misery index to assess the effects of macroeconomic stability, this study seeks to enrich the literature.
Cloud Computing in Insurance: Emerging Trends and Transformative Technologies
Authors: - Venkatakrishna Nukala
Published: October 2024

This article examines the transformative impact of emerging cloud computing trends on the insurance industry. As insurers increasingly adopt cloud-based solutions, several key technologies are poised to revolutionize operations, customer experiences, and business models. The integration of artificial intelligence and machine learning is enhancing underwriting accuracy, claims processing efficiency, and fraud detection capabilities. Edge computing is enabling real-time data analysis and decision-making, while serverless architectures are optimizing resource allocation and reducing costs. Blockchain technology is improving data security, transparency, and trust in transactions. Additionally, hybrid and multi-cloud strategies are providing insurers with greater flexibility and regulatory compliance. This comprehensive analysis explores these trends, their interconnections, and their potential to drive innovation in insurance. The article concludes by discussing the implications of these advancements for insurers, policyholders, and the broader financial services ecosystem, offering insights into future research directions and industry adaptations.
Cataract Epidemiology and Prevention: Strategies for Reducing Global Burden
Authors: - Shalini Verma , - Ashish Prajapati , - Khushbu Chaudhary
Published: October 2024

Cataract, characterized by the clouding of the eye's clear lens, is the leading cause of blindness worldwide. To achieve optimal image quality on the retina, the human lens and cornea must first refract light accurately. With aging, the human lens undergoes physical, biochemical, and morphological changes, leading to opacification. The primary mechanisms of cataract formation involve the modification, aggregation, and precipitation of crystalline. While most cataracts result from age-related degeneration, they can also arise secondary to trauma or as a consequence of other diseases, though cataracts are rare in children. This review article provides an in-depth examination of the anatomy and physiology of the lens, different types of cataracts—including diabetic, pediatric, and age-related cataracts—and the management of cataracts through surgical and pharmacological treatments.
Exploring Quantum Entanglement for Secure Communication: A Study on Quantum Cryptography Protocols
Authors: - Dr. Rajeev Trivedi , - Dr. C. S. Sharma
Published: October 2024

Quantum Ensnarement, a wonder at the heart of quantum mechanics, has risen as a promising road for revolutionizing secure communication through Quantum Cryptography. This inquiries about digs into the investigation of Quantum Ensnarement as an establishment for creating vigorous and secure communication conventions. The think about includes an in-depth examination of different Quantum Cryptography conventions, exploring their hypothetical underpinnings and viable executions. The investigate strategy utilizes a combination of hypothetical modeling and exploratory approval to survey the viability and security of Quantum Cryptography conventions in assorted scenarios. Key angles beneath investigation incorporate the era, conveyance, and utilization of snared particles to build up secure communication channels. Quantum key dispersion (QKD) conventions, such as BB84 and E91, will be inspected in detail to comprehend their qualities, vulnerabilities, and potential for commonsense execution in real-world communication frameworks. Moreover, the inquire about investigates the challenges and progressions in quantum innovation that contribute to the effective arrangement of Quantum Cryptography conventions.
Al in Secondary Classroom: A Study of Its Impact on Student Engagement, Personalized Learning, and Academic Progress
Authors: - Kavita Sanghvi
Published: October 2024

Artificial Intelligence (AI) has increasing woven itself into the fabric of our lives yet its full potential in education remains untapped. Despite its widespread use AI has not been seamlessly integrated within our education system. To ascertain the transformative impact of AI in education, this study explored the use of AI tools over a one-week period in classroom instruction. Following this, students showcased their learning using AI tools to key stakeholders.
The level of student engagement was closely monitored, and an assessment was conducted to evaluate their academic progress. This study provides valuable insights for educators to inform future curriculum planning and instructional strategies.
Consequence of Orange Theory Fitness Training on Selected Health Related Physical Fitness Variables among Obese
Authors: - V.A.MANICKAM , - S. HARRIS LAMUEL PRAKASH
Published: October 2024

Abstract
The main task of the study was to find out Consequence of orange theory fitness training on Selected Health Related Physical Fitness Variables among Obese. To achieve the task of the study Forty class-I obese school boys were selected from various schools in Tuticorin were selected as subjects and their age ranged from 12-15 years only. The selected subjects were divided into two equal groups namely experimental group (20) and control group (20). The experimental group participated in orange theory fitness training. Pre and post-test method were followed. The experimental training was adopted for eight weeks on three days a week and control group was not exposed to experimental treatment. The selected variables namely flexibility, cardio respiratory endurance and muscular endurance. The above selected variables were tested through Flexibility (sit and reach in centimetre), Cardio Vascular Endurance (1.6 mile run in five minutes), and Muscular Endurance (bent knee sit-ups). The collected data were statistically analyses using dependent 't' test. The level of confidence was fixed at 0.05 for all cases. The result of the study showed that there was a significant improvement in flexibility, cardio respiratory endurance and muscular endurance among class -I obese school boys due to orange theory fitness training.
Integrated Deep Learning Architectures for Perception, Control, and Decision-making in Robotics: a Framework for Sensing, Cognition, and Transparent Decision-making
Authors: - Ruchik Kashyapkumar Thaker
Published: October 2024

The increasing complexity of robotic applications demands innovative approaches for addressing problems that lack analytical solutions, with deep learning (DL) emerging as a key tool for enabling robots to learn and adapt in dynamic environments. This survey reviews existing DL techniques in robotics, categorizing the major challenges and exploring successful solutions that leverage DL for perception, control, and decision-making. We discuss the use of modular versus end-to-end DL architectures, providing guidelines for selecting appropriate model structures and training strategies. The review also examines advancements in neuro-robotics systems (NRS), where the convergence of neuroscience and robotics is driving the development of robots with embodied intelligence, enabling more natural human-robot interactions. Recent progress in neural mechanisms for perception, cognition, learning, and control is highlighted, offering insights into creating future neuro-robots. Furthermore, we address the challenge of uncertainty estimation in neural networks, crucial for reliable robotic decision-making, and evaluate existing frameworks such as Bayesian belief networks and Monte Carlo sampling that improve uncertainty modeling without requiring architectural changes. Lastly, we explore efforts to enhance transparency in robotic systems through integrated reasoning and learning methods, focusing on architectures that combine logical reasoning with deep learning to provide explainable decision-making. This survey aims to offer a structured overview of current research and guide future developments in neuro-robotics.
IMPLEMENTASI KEBIJAKAN DINAS PENDIDIKAN KEPEMUDAAN DAN OLAHRAGA KABUPATEN KAMPAR DALAM PEMERATAAN TENAGA GURU KONTRAK DALAM MENDAPATKAN TUNJANGAN PROFESI
Authors: Kausarri Muhammad Rezieq , Yuslaini Nina
Published: October 2024

Program pemerataan tenaga guru kontrak merupakan salah satu Upaya  penting dalam mengurangi masalah kekurangan tenaga guru kontrak disekolah negeri milik pemerintah daerah, termasuk di kabupaten kampar. Kecamatan Kampa dipilih sebagai fokus implementasi program ini oleh Dinas Pendidikan Kepemudaan dan Olahraga untuk mengatasi masalah kebutuhan tenaga guru yang signifikan. Implementasi program ini melibatkan berbagai strategi, antara lain penguatan kerja sama antar sektor serta peningkatan edukasi dan sosialisasi kepada  tenaga guru kontrak tentang peningkatan kualitas sumber daya manusia, monitoring dan menyesuaikan strategi interverensi sesuai kebutuhan yang terindentifikasi. Tipe penelitian yang digunakan dalam penelitian ini yaitu dengan menggunakan metode deskriptif kualitatif. Hasil dari penelitian ini menunjukan peningkatan kesadaran pemerintah daerah tentang program pemerataan tenaga guru kontrak seperti perubahan perilaku yang lambat tetap menjadi fokus perbaikan dalam menjaga keberlanjutan program ini. Program pemerataan tenaga guru kontrak oleh Dinas pendidikan kepemudaan dan olahraga kabupaten kampar menunjukan progress yang positif dalam upaya masalah kebutuhan tenaga guru kontrak. Untuk memastikan program ini akan berhasil dalam jangka panjang dan meningkatkan kebutuhan tenaga guru kontrak secara keseluruhan, langkah selanjutnya diperlukan.
Protein kinases as therapeutic targets for Alzheimer’s disease: a brief review
Authors: Silva Isabela Marie Fernandes , dos Reis Rosa Franco Graziella , Gontijo Vanessa Silva , Viegas Claudio
Published: October 2024

Alzheimer’s disease (AD) is a progressive and incurable neurodegenerative disorder, with an unknown etiology and a multifactorial pathophysiology characterized by protein misfolding, neuroinflammation, and neuronal loss. There are three well-discussed main hypotheses for the pathophysiology of AD, which are related to i) the accumulation of amyloid β (Aβ) protein aggregates in the extracellular space, ii) deposition of hyperphosphorylated tau fragments as neurofibrillary tangles, and iii) dysregulation of hemostasis of some neurotransmitters involved in the disease, such as acetylcholine (ACh) and glutamate. The association of all these factors is responsible for installing oxidative stress and neuroinflammation, which contribute to progressive neuronal death in specific brain regions. More recently, other remarkable pathological characteristics have been described, involving changes in all levels of cellular components, especially in the action and function of protein kinases. These enzymes are crucial for cellular regulation since they play a pivotal role in the phosphorylation of protein substrates by transferring a phosphate group from the ATP molecule to threonine, serine, or tyrosine residues. In more recent studies, some kinases have been especially reported by their role in inflammatory and oxidative processes associated to AD, such as cAMP-dependent protein kinase A (PKA), cyclin-dependent protein kinase 5 (CDK5), glycogen synthase kinase 3β (GSK-3β), and the microtubule affinity regulatory kinases (MARKs). Under homeostatic conditions, protein kinases act as cellular signals, directing physiological responses, but in AD pathogenesis, these enzymes have an exacerbated activity in the brain, justifying the need for a better comprehension of their function and role, and how new kinase inhibitors could lead to innovative drugs. In this context, this brief review aimed to compile the literature data related to the most recent efforts and strategies in Medicinal Chemistry in the discovery of new kinase inhibitors, opening new ways to AD therapeutics.
Summary of the Groundwater Recharge from the South West African Monsoon: A Transect from the Guinea Coast to the Hombori Mountains in Mali
Authors: Condé Soumaïla , Soumah Fodé Salifou , SYLLA Fatoumata , Lambs Luc , Moussa Issam , Favreau Guillaume , Grippa Manuela , Mougin Eric
Published: October 2024

There is an increasing demand on water supplies in semi-arid regions. There is an urgent need to better understand the recharge process of groundwater in these areas, but there an underrepresentatity of long-term data in these regions ay a global scale. we present the seasonal variations of groundwater over a two-three-year period over a 1500 km transect from the Gulf of Guinea coast to inland Mount Hombori in Mali. The results show a strong seasonal and interannual variability, with important evaporation processes for surface and shallow groundwater with rapid infiltration processes. The continental /latitude effect is low along the first 500 km in Guinea, and decrease slowly with the reduction of rainfall and air moisture in direction of Sahel.
Effect of Food-Grade Pharmaceutical Excipients on Physicochemical Behaviour of Quercetin Nanocomposites: Thermal and Non-Thermal Analysis
Authors: Sachi Das Sabya , Prasad Verma Priya Ranjan , Kumar Singh Sandeep
Published: October 2024

In this study, the compatibility of Quercetin (QC) nanocomposites with some selective food-grade pharmaceutical excipients was assessed using various thermal (DSC and TGA), non-thermal (P-XRD, FT-IR, and RAMAN spectroscopy, and FESEM) techniques. All the techniques were simultaneously used and correlated to detect the QC's compatibility with the selected excipients (CO, CCO, OA, T20, T60, and T80). DSC-TG studies showed that QC-CO and QC-T60 samples exhibited irregular degradation patterns, causing the drug's transformation from crystalline to amorphous. P-XRD results showed that the crystalline behavior of QC was retained in all the samples. However, the peak intensities were reduced and shifted in some samples. The Davg. value for all samples, including pure QC, was 26.80-76.07 nm. FT-IR and RAMAN studies demonstrated that bonds including –C=O stretching, C-C stretching (ring A), and -OH bonds (in ring A, B, and C) in pure QC play a crucial role in its interaction with excipients. Furthermore, the excipients' effect on QC's morphology using FESEM showed smoothening, fragmentation, and agglomeration of the drug. In conclusion, the possible drug-excipient incompatibility can be potentially determined with the help of these analytical methods. The physicochemical studies from this work may provide immense knowledge for the researchers and manufacturers involved in quercetin-based pharmaceutical and/or nutraceutical formulations.
Palaeohelicopsyche netnetdaida sp.n., a first species of Helicopsychidae (Insecta: Trichoptera) from Eocene Rovno amber
Authors: Melnitsky Stanislav I. , Ivanov Vladimir D. , Legalov Andrei A. , Perkovsky Evgeny E.
Published: October 2024

A new caddisfly species Palaeohelicopsyche netnetdaida sp. nov. (Helicopsychidae) is described and illustrated from Rovno amber (Priabonian). The family Helicopsychidae is recorded for Rovno amber for the first time. The list of caddisflies known from Rovno amber includes 43 named species.
A second species of the subgenus Neomicrambe (Coleoptera: Cryptophagidae: Micrambe) from Danish amber
Authors: Lyubarsky Georgy Yu. , Legalov Andrei A. , Vasilenko Dmitry V. , Perkovsky Evgeny E.
Published: October 2024

Micrambe danica sp. nov., a new species of Cryptophagidae (Coleoptera), is described and illustrated from Eocene Danish amber. It differs from M. tristis Lyubarsky et Perkovsky, 2024 from Danish amber by its large pronotal callosity. Extant species of subgenus are distributed on the highest mountains of Africa from southern Ethiopia to Tanzania. The supposed migration of the subgenus to Africa is discussed.
India-China Economic Directions – Towards Fourth Industrial Revolution
Authors:   Chinese Studies at Jawaharlal Nehru University, Kondapalli S.
Published: October 2024

As the second and fifth largest economies in the world, China and India have embraced the vicissitudes of world economy and re-adjusting their policies to strengthen their economies as well as to usher in a multipolar world. Both have launched their long-term strategic plans for self-strengthening in Made in China 2025, “socialist modernisation” by 2049 by China and Vikas (Development)/Viksit Bharat (Developed India) 2047 campaigns by India. In its current 14th Five Year Plan, China had announced a shift towards an innovation-driven model, emphasising technological advancements and domestic consumption. India had also launched Make in India, Skill India, Digital India and other plans. Despite challenges, both of these countries are currently experiencing massive social transformations in human resources development, talent generation, industrial growth specifically knowledge economy and other related fields. Both China and India have also been aware of the socio-economic stress that globalisation has set in and hence have undertaken social welfare policies like addressing “san nong”, “jandhan” (direct bank transfers) and other schemes. It is argued that, despite problems, the efforts of China and India are transforming the socio-economic fabrics of these countries.
Marka Nefretinin Nedenlerinin ve Sonuçlarının Tüketicilerin Gıda Ürünleri Tercihleri Açısından İncelenmesi
Authors: Yağcı Avni Can , Demiral Deniz Julia
Published: October 2024

Tüketicilerin markaya karşı geliştirdiği yoğun düzeyde olumsuz duygu olarak tanımlanabilen marka nefreti, markaya ekonomik zararın yanı sıra prestij ve imaj kaybı ile birlikte olumsuz tüketici-marka ilişkileri olarak yansımaktadır. Günümüzde globalleşme ve teknolojik gelişmeler ile her sektörde görülebilen marka nefretinin araştırılması bu nedenle markaların strateji geliştirebilmeleri için önem taşımaktadır. Bu araştırmanın amacı, sembolik uyuşmazlık, ideolojik uyuşmazlık ve olumsuz geçmiş deneyimler gibi marka nefretinin öncül değişkenlerinin tüketicilerin memnun kalmadığı çeşitli gıda ürünleri özelinde marka nefreti, marka kaçınması ve olumsuz ağızdan ağıza iletişim gibi sonuçlara neden olup olmadığını tespit etmektir. Bu doğrultuda kantitatif ve tanımsal bir araştırma tasarımı yapılmıştır. Kolayda ve kartopu örnekleme yöntemleri ile 191 katılımcıdan toplanan veriler LISREL 8.8 ve SPSS 25.0 paket programları kullanılarak keşifsel faktör analizi, doğrulayıcı faktör analizi, yapısal eşitlik modeli ve yol analizi gibi ileri bazı analiz yöntemleri ile analiz edilmiştir. Çalışmanın bulgularına göre, sembolik ve ideolojik uyuşmazlıkların marka nefretini olumlu etkilediği ve olumsuz geçmiş deneyimlerin ise marka nefreti üzerinde anlamlı bir etkisinin olmadığı sonucuna varılmıştır. Ayrıca, marka nefretinin marka kaçınması ve olumsuz ağızdan ağıza iletişim gibi sonuçlara neden olduğu tespit edilmiştir.
A Study to Assess the Effectiveness of Educational Programme on Knowledge and Attitude of Mothers Regarding Child abuse in Selected Areas at Melmaruvathur, Chengalpattu District
Authors: Srignanasoundari E.
Published: October 2024

Child abuse is the physical, sexual, emotional maltreatment or neglect of a children. It occurs in all areas where the child interacts with in and around them. Children who experience child abuse more likely to become involved in criminal activity. In India knowledge of child abuse is poor and very low cases are reported. Aim: To assess the knowledge and attitude of mothers in and around Melmaruathur, Kancheepuram District. Materials & Methods: Mothers were directed to fill out a Questionnaire to assess the knowledge and likert scale used to assess their attitude of child abuse. After that educational programme was conducted on prevention of child abuse. Responses were recorded & analyzed. The findings of the present study revealed that in overall knowledge of mothers regarding child abuse 87% have inadequate, 13% have moderate adequate and none of them have adequate knowledge. When compare to the various types of child abuse, knowledge about sexual abuse was 53% and others less than 35%. In attitude of mothers 15% have good and 85% have fair and no one have got poor attitude. Ater the education 80 % mothers had adequate knowledge, 20% had moderately adequate knowledge. 85% had good attitude, 10% had fair attitude on child abuse and 5% had poor attitude. Conclusion: Mothers of selected area there have deficient knowledge on general information of child abuse, physical abuse, emotional abuse and have moderate knowledge on sexual abuse, impact of child abuse on life of children. Statistically there is no significant relationship between knowledge and attitude.
Biases in Exoplanet Transmission Spectra Introduced by Limb-darkening Parametrization
Authors: Coulombe Louis-Philippe , Roy Pierre-Alexis , Benneke Björn
Published: October 2024

One of the main endeavors of the field of exoplanetary sciences is the characterization of exoplanet atmospheres on a population level. The current method of choice to accomplish this task is transmission spectroscopy, where the apparent radius of a transiting exoplanet is measured at multiple wavelengths in search of atomic and molecular absorption features produced by the upper atmosphere constituents. To extract the planetary radius from a transit light curve, it is necessary to account for the decrease in luminosity away from the center of the projected stellar disk, known as limb darkening. Physically motivated parametrizations of limb darkening, in particular of the quadratic form, are commonly used in exoplanet transit light-curve fitting. Here, we show that such parametrizations can introduce significant wavelength-dependent biases in the transmission spectra currently obtained with all instrument modes of the JWST, and thus have the potential to affect atmospheric inferences. To avoid such biases, we recommend the use of standard limb-darkening parametrizations with wide uninformative priors that allow for nonphysical stellar intensity profiles in the transit fits, and thus for a complete and symmetrical exploration of the parameter space. We further find that fitting the light curves at the native resolution results in errors on the measured transit depths that are significantly smaller compared to light curves that are binned in wavelength before fitting, thus potentially maximizing the amount of information that can be extracted from the data.
Modeling of Long-term Afterglow Counterparts to Gravitational Wave Events: The Full View of GRB 170817A
Authors: Ryan Geoffrey , van Eerten Hendrik , Troja Eleonora , Piro Luigi , O’Connor Brendan , Ricci Roberto
Published: October 2024

The arrival of gravitational wave astronomy and a growing number of time-domain-focused observatories are set to lead to an increasing number of detections of short gamma-ray bursts (GRBs) launched with a moderate inclination to Earth. Being nearby events, these are also prime candidates for very long-term follow-up campaigns and very long-baseline interferometry, which has implications for multi-messenger modeling, data analysis, and statistical inference methods applied to these sources. Here, we present a comprehensive modeling update that directly incorporates into afterglowpy astrometric observations of the GRB position, Poissonian statistics for faint sources, and modeling of a trans-relativistic population of electrons. We use the revolutionary event GW170817 to demonstrate the impact of these extensions both for the best-fit physics parameters and model selection methods that assess the statistical significance of additional late-time emission components. By including in our analysis the latest Chandra X-ray observations of GRB 170817A, we find only weak evidence (≲2σ) for a new emission component at late times, which makes for a slightly more natural fit to the centroid evolution and prediction for the external medium density.
Evidence for a Fast Soft X-Ray Wind in M82 from XMM-RGS
Authors: Boettcher Erin , Hodges-Kluck Edmund
Published: October 2024

Starburst wind models predict that metals and energy are primarily carried out of the disk by hot gas (T > 106 K), but the low energy resolution of X-ray CCD observations results in large uncertainties on the mass and energy loading. Here, we present evidence for a fast soft X-ray wind from the prototypical starburst galaxy M82 using deep archival observations from the Reflection Grating Spectrometer on XMM-Newton. After characterizing the complex line-spread function for the spatially extended outflow (

≈
4
′

), we perform emission-line fitting to measure the velocity dispersion, σ

v
, from O viii (0.65, 0.77 keV), Ne x (1.02 keV), and Mg xii (1.47 keV). For the T ≈ 3 × 106 K gas, O viii yields a velocity dispersion of

σ
v

=

1160

−
90

+
100

km s−1, implying a wind speed that is significantly above the escape velocity (v
esc ≲ 450 km s−1). Ne x (

σ
v

=

550

−
150

+
130

km s−1) and Mg xii (σ

v
< 370 km s−1) show less velocity broadening than O viii, hinting at a lower wind speed or smaller opening angle on the more compact spatial scales traced by the T ≈ (0.6−1) × 107 K gas. Alternatively, these higher energy emission lines may be dominated by shock-heated gas in the interstellar medium. Future synthesis of these measurements with performance verification observations of the E = 2−12 keV wind in M82 from the Resolve microcalorimeter on the X-ray Imaging and Spectroscopy Mission will inform the phase structure and energy budget of the hot starburst wind.
Almost All Carbon/Oxygen White Dwarfs Can Host Double Detonations
Authors: Shen Ken J. , Boos Samuel J. , Townsley Dean M.
Published: October 2024

Double detonations of sub-Chandrasekhar-mass white dwarfs (WDs) in unstably mass-transferring double WD binaries have become one of the leading contenders to explain most Type Ia supernovae. However, past theoretical studies of the explosion process have assumed relatively ad hoc initial conditions for the helium shells in which the double detonations begin. In this work, we construct realistic C/O WDs to use as the starting points for multidimensional double detonation simulations. We supplement these with simplified one-dimensional detonation calculations to gain a physical understanding of the conditions under which shell detonations can propagate successfully. We find that C/O WDs ≲1.0 M
⊙, which make up the majority of C/O WDs, are born with structures that can support double detonations. More massive C/O WDs require ∼10−3
M
⊙ of accretion before detonations can successfully propagate in their shells, but such accretion may be common in the double WD binaries that host massive WDs. Our findings strongly suggest that if the direct impact accretion stream reaches high enough temperatures and densities during mass transfer from one WD to another, the accreting WD will undergo a double detonation. Furthermore, if the companion is also a C/O WD ≲1.0 M
⊙, it will undergo its own double detonation when impacted by the ejecta from the first explosion. Exceptions to this outcome may explain the newly discovered class of hypervelocity supernova survivors.
Concept of a Double Tilted Rowland Spectrograph for X-Rays
Authors: Günther Hans Moritz , DeRoo Casey T. , Heilmann Ralf K. , Hertz Edward
Published: October 2024

High-resolution spectroscopy in soft X-rays (<2 keV) requires diffractive elements to resolve any astrophysically relevant diagnostics, such as closely spaced lines, weak absorption lines, or line profiles. The Rowland torus geometry describes how gratings and detectors need to be positioned to optimize the spectral resolving power. We describe how an on-axis Rowland geometry can be tilted to accommodate blazed gratings. In this geometry, two channels with separate optical axes can share the same detectors (double tilted Rowland spectrograph). Small offsets between the channels can mitigate the effect of chip gaps and reduce the alignment requirements during the construction of the instrument. The double tilted Rowland spectrograph concept is especially useful for subapertured mirrors, because it allows an effective use of space in the entrance aperture of a spacecraft. One mission that applies this concept is the Arcus Probe.
Dynamical Consequence of Shadows Cast to the Outer Protoplanetary Disks. I. Two-dimensional Simulations
Authors: Su Zehao , Bai Xue-Ning
Published: October 2024

There has been increasing evidence of shadows from scattered light observations of outer protoplanetary disks (PPDs) cast from the (unresolved) disk inner region, while in the meantime these disks present substructures of various kinds in the submillimeter. As stellar irradiation is the primary heating source for the outer PPDs, the presence of such shadows thus suggests inhomogeneous heating of the outer disk in azimuth, leading to a “thermal forcing” with dynamical consequences. We conduct a suite of idealized two-dimensional disk simulations of the outer disk with azimuthally varying cooling prescription to mimic the effect of shadows, generally assuming the shadow is static or slowly rotating. The linear response to such shadows is two-armed spirals with the same pattern speed as the shadow. Toward the nonlinear regime, we find that shadows can potentially lead to the formation of a variety of types of substructures including rings, spirals, and crescents, depending on viscosity, cooling time, etc. We have conducted systematic and statistical characterization of the simulation suite, and as thermal forcing from the shadow strengthens, the dominant form of shadow-induced disk substructures change from spirals to rings, and eventually to crescents/vortices. Our results highlight the importance of properly modeling the dynamical impact of inhomogeneous stellar irradiation, while calling for more detailed modeling incorporating more realistic disk physics.
A Multifrequency View of the Radio Phoenix in the A85 Cluster
Authors: Raja Ramij , Rahaman Majidul , Datta Abhirup , Smirnov Oleg M.
Published: October 2024

Radio phoenices are complex and filamentary diffuse radio sources found in both merging and relaxed clusters. The formation of these sources has been proposed to be due to adiabatic compression of old active galactic nucleus plasma in shock waves. Most of the previous spectral studies of these sources have been limited to integrated spectral indices, which were found to be very steep and show a curved spectrum. Here, we have performed a multifrequency investigation of the radio phoenix in the A85 cluster. Owing to the sensitive high-resolution observations, we found some of the finer filamentary structures that had been previously undetected. We produced resolved spectral index maps of the radio phoenix between 323, 700, and 1280 MHz. The orientation of the filaments, as well as the gradient across the spectral index maps, suggest the possible direction of the shock motion from northeast to southwest. The integrated spectrum of the radio phoenix was found to be very steep and curved toward high frequencies. Furthermore, the spectral index of the filaments was found to be less steep compared to the nonfilamentary regions, implying greater energy injection in the filaments. The observed features in the radio phoenix in the A85 cluster seem to be in support of an adiabatic shock compression mechanism.
Multiple New or Updated Satellite Total Solar Irradiance (TSI) Composites (1978–2023)
Authors: Connolly Ronan , Soon Willie , Connolly Michael , Cionco Rodolfo Gustavo , Elias Ana G. , Henry Gregory W. , Scafetta Nicola , Velasco Herrera Víctor M.
Published: October 2024

Several total solar irradiance (TSI) satellite missions have been carried out since 1978. None of these missions have lasted more than one to two solar cycles (SCs), and each mission implies a slightly different absolute TSI baseline. Nonetheless, several satellite composites have been developed by compositing satellite data from different missions to form an almost continuous daily record for the satellite era. However, disconcertingly, each mission has implied slightly different changes in TSI between consecutive solar minima and solar maxima. Some groups have developed adjustments to individual missions that have substantially reduced these differences. Others prefer to use the original data published by the satellite science teams. Some TSI composites average together conflicting records, while others prioritize specific records over others. Here, we compare four existing composites to 17 new alternative series based on the available satellite data. These 21 TSI series are statistically sorted into six groups of three to four series each. We found that the six groups suggest different intercycle trends between solar minima. We compare the groups to eight daily resolved solar proxy-based TSI reconstructions and to daily sunspot numbers. Excellent agreement is obtained over one to two SCs, but significant differences are observed over longer timescales for each group. Therefore, we have assembled all these time series (old and new) into a large and new TSI data set for use by the scientific community. Versions scaled to 1 au (for studying solar variability) or in situ values at Earth (for studying solar/terrestrial interactions) are provided at daily, monthly, and yearly resolutions.
New Insights into Type-I Solar Noise Storms from High Angular Resolution Spectroscopic Imaging with the Upgraded Giant Metrewave Radio Telescope
Authors: Mondal Surajit , Kansabanik Devojyoti , Oberoi Divya , Dey Soham
Published: October 2024

Type-I solar noise storms are perhaps the most commonly observed active radio emissions from the Sun at meter-wavelengths. Noise storms have a long-lived and wideband continuum background with superposed islands of much brighter narrowband and short-lived emissions, known as type-I bursts. There is a serious paucity of studies focusing on the morphology of these two types of emissions, primarily because of the belief that coronal scattering will always wash out any features at small angular scales. However, it is important to investigate their spatial structures in detail to make a spatio-temporal connection with observations at extreme-ultraviolet/X-ray bands to understand the detailed nature of these emissions. In this work, we use high angular resolution observations from the upgraded Giant Metrewave Radio Telescope to demonstrate that it is possible to detect structures with angular scales as small as ∼9″, about three times smaller than the smallest structure reported to date from noise storms. Our observations also suggest that while the individual type-I bursts are narrowband in nature, the bursts are probably caused by traveling disturbance(s) inducing magnetic reconnections at different coronal heights, and thus leading to correlated change in the morphology of the type-I bursts observed at a wide range of frequencies.
TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Jayaraman Rahul , Rappaport Saul A. , Powell Brian , Handler Gerald , Omohundro Mark , Gagliano Robert , Kostov Veselin , Fuller Jim , Kurtz Donald W. , Zhang Valencia , Ricker George
Published: October 2024

The Transiting Exoplanet Survey Satellite (TESS) has enabled the discovery of numerous tidally tilted pulsators (TTPs), which are pulsating stars in close binaries where the presence of a tidal bulge has the effect of tilting the primary star’s pulsation axes into the orbital plane. Recently, the modeling framework developed to analyze TTPs has been applied to the emerging class of triaxial pulsators, which exhibit nonradial pulsations about three perpendicular axes. In this work, we report on the identification of the second-ever discovered triaxial pulsator, with 16 robustly detected pulsation multiplets, of which 14 are dipole doublets separated by 2ν
orb. We jointly fit the spectral energy distribution and TESS light curve of the star, and find that the primary is slightly evolved off the zero-age main sequence, while the less massive secondary still lies on the zero-age main sequence. Of the 14 doublets, we associate eight with Y
10x
modes and six with novel Y
10y
modes. We exclude the existence of Y
11x
modes in this star and show that the observed pulsation modes must be Y
10y
. We also present a toy model for the triaxial pulsation framework in the context of this star. The techniques presented here can be utilized to rapidly analyze and confirm future triaxial pulsator candidates.
The Manhattan Suite: Accelerated Galaxy Evolution in the Early Universe
Authors: Rennehan Douglas
Published: October 2024

Observational advances have allowed the detection of galaxies, protoclusters, and galaxy clusters at higher and higher redshifts, opening a new view into extreme galaxy evolution. I present an argument that the high-redshift, massive galaxies discovered over the last decade are really the most massive galaxies within protocluster cores of galaxy clusters at z ∼ 2, and that they are the partial descendants of same galaxies discovered by JWST at z ∼ 9. To that end, I present The Manhattan Suite, a set of 100 high resolution zoom-in simulations of the most massive galaxy clusters, out to 9 R
vir, selected at z = 2 from a (1.5 cGpc)3 parent volume, and simulated using the simba model. Unlike other cluster suites, my selection at z = 2 ensures that these systems are biased in a similar fashion to observations, in that they should be the brightest and the most massive by construction at z ≳ 2. I show that my sample is able to reproduce extremely star-bursting protoclusters such as SPT2349-56, high-redshift galaxy clusters XLSSC122 and JKCS041, and the wealth of massive (sometimes quenched) galaxies at z ≳ 3 and up to z ∼ 9. I argue that these systems are intimately linked, and represent the same evolutionary history.
Full Stokes-vector Inversion of the Solar Mg ii h and k Lines
Authors: Li Hao , del Pino Alemán Tanausú , Trujillo Bueno Javier
Published: October 2024

The polarization of the Mg ii h and k resonance lines is the result of the joint action of scattering processes and the magnetic field–induced Hanle, Zeeman, and magneto-optical effects, thus holding significant potential for the diagnostic of the magnetic field in the solar chromosphere. The Chromospheric LAyer Spectro-Polarimeter sounding-rocket experiment, carried out in 2019, successfully measured at each position along the 196″ spectrograph slit the wavelength variation of the four Stokes parameters in the spectral region of this doublet around 280 nm, both in an active-region plage and in a quiet region close to the limb. We consider some of these CLASP2 Stokes profiles and apply to them the recently developed HanleRT Tenerife Inversion Code, which assumes a one-dimensional model atmosphere for each spatial pixel under consideration (i.e., it neglects the effects of horizontal radiative transfer). We find that the nonmagnetic causes of symmetry breaking, due to the horizontal inhomogeneities and the gradients of the horizontal components of the macroscopic velocity in the solar atmosphere, have a significant impact on the linear polarization profiles. By introducing such nonmagnetic causes of symmetry breaking as parameters in our inversion code, we can successfully fit the Stokes profiles and provide an estimation of the magnetic field vector. For example, in the quiet region pixels, where no circular polarization signal is detected, we find that the magnetic field strength in the upper chromosphere varies between 1 and 20 G.
Magnetic Fields in a Sample of Planet-hosting M Dwarf Stars from Kepler, K2, and TESS Observed by APOGEE
Authors: Wanderley Fábio , Cunha Katia , Smith Verne V. , Kochukhov Oleg , Souto Diogo , Allende Prieto C. , Mahadevan Suvrath , Majewski Steven R. , Muirhead Philip S. , Pinsonneault Marc , Terrien Ryan
Published: October 2024

Stellar magnetic fields have a major impact on space weather around exoplanets orbiting low-mass stars. From an analysis of Zeeman-broadened Fe i lines measured in near-infrared SDSS/APOGEE spectra, mean magnetic fields are determined for a sample of 29 M dwarf stars that host closely orbiting small exoplanets. The calculations employed the radiative transfer code Synmast and MARCS stellar model atmospheres. The sample M dwarfs are found to have measurable mean magnetic fields ranging between ∼0.2 and ∼1.5 kG, falling in the unsaturated regime on the 〈B〉 versus P
rot plane. The sample systems contain 43 exoplanets, which include 23 from Kepler, nine from K2, and nine from Transiting Exoplanet Survey Satellite. We evaluated their equilibrium temperatures, insolation, and stellar habitable zones and found that only Kepler-186f and TOI-700d are inside the habitable zones of their stars. Using the derived values of 〈B〉 for the stars Kepler-186 and TOI-700 we evaluated the minimum planetary magnetic field that would be necessary to shield the exoplanets Kepler-186f and TOI-700d from their host star’s winds, considering reference magnetospheres with sizes equal to those of the present-day and young Earth, respectively. Assuming a ratio of 5% between large- to small-scale B-fields, and a young-Earth magnetosphere, Kepler-186f and TOI-700d would need minimum planetary magnetic fields of, respectively, 0.05 and 0.24 G. These values are considerably smaller than Earth’s magnetic field of 0.25 G ≲ B ≲ 0.65 G, which suggests that these two exoplanets might have magnetic fields sufficiently strong to protect their atmospheres and surfaces from stellar magnetic fields.
The State of Solar Wind Heavy Ions in Interplanetary Coronal Mass Ejection–Driven Geomagnetic Storms
Authors: Wang Cong , He Fei , Zhang Xiaoxin
Published: October 2024

During geomagnetic storms, which are the primary periods for heavy ions from the solar wind to enter Earth’s magnetospheric space, the charge state of solar wind heavy ions during these storms has significant implications for studying the distribution and effects of heavy ions in the magnetosphere. We analyzed the states and variations of heavy ions during 158 interplanetary coronal mass ejection (ICME)–driven geomagnetic storm events using data from the Advanced Composition Explorer satellite and examined four of these events in detail. We found that the increase in the average charge state of heavy ions such as O, Mg, Si, and Fe is positively correlated with the intensity of the geomagnetic storm. Regarding the abundance ratio of heavy ions such as Ne, Mg, Si, and Fe relative to oxygen ions, the rate and magnitude of increase in abundance ratios during extreme geomagnetic storms (Kp = 9) triggered by ICME events are significantly higher than those during other levels of geomagnetic storms. Additionally, we observed that although the average charge states of heavy ions such as O and Fe are correlated with the geomagnetic storm intensity induced by ICMEs, there are significant individual differences in the charge state variations of heavy ions.
Regulation of Solar Wind Electron Temperature Anisotropy by Collisions and Instabilities
Authors: Yoon Peter H. , Salem Chadi S. , Klein Kristopher G. , Martinović Mihailo M. , López Rodrigo A. , Seough Jungjoon , Sarfraz Muhammad , Lazar Marian , Shaaban Shaaban M.
Published: October 2024

Typical solar wind electrons are modeled as being composed of a dense but less energetic thermal “core” population plus a tenuous but energetic “halo” population with varying degrees of temperature anisotropies for both species. In this paper, we seek a fundamental explanation of how these solar wind core and halo electron temperature anisotropies are regulated by combined effects of collisions and instability excitations. The observed solar wind core/halo electron data in (β
∥, T
⊥/T
∥) phase space show that their respective occurrence distributions are confined within an area enclosed by outer boundaries. Here, T
⊥/T
∥ is the ratio of perpendicular and parallel temperatures and β
∥ is the ratio of parallel thermal energy to background magnetic field energy. While it is known that the boundary on the high-β
∥ side is constrained by the temperature anisotropy-driven plasma instability threshold conditions, the low-β
∥ boundary remains largely unexplained. The present paper provides a baseline explanation for the low-β
∥ boundary based upon the collisional relaxation process. By combining the instability and collisional dynamics it is shown that the observed distribution of the solar wind electrons in the (β
∥, T
⊥/T
∥) phase space is adequately explained, both for the “core” and “halo” components.
A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Chamberlain Katie , Patel Ekta , Besla Gurtina , Torrey Paul , Rodriguez-Gomez Vicente
Published: October 2024

The merger timescales of isolated low-mass pairs (108 < M
* < 5 × 109
M
⊙) on cosmologically motivated orbits have not yet been studied in detail, though isolated high-mass pairs (5 × 109 < M
* < 1011
M
⊙) have been studied extensively. It is common to apply the same separation criteria and expected merger timescales of high-mass pairs to low-mass systems, however, it is unclear if their merger timescales are similar, or if they evolve similarly with redshift. We use the Illustris TNG100 simulation to quantify the merger timescales of isolated low-mass and high-mass major pairs as a function of cosmic time, and explore how different selection criteria impact the mass and redshift dependence of merger timescales. In particular, we present a physically motivated framework for selecting pairs via a scaled separation criterion, wherein pair separations are scaled by the virial radius of the primary’s Friends-of-Friends (FoF) group halo (r
sep < 1 R
vir). Applying these scaled separation criteria yields equivalent merger timescales for both mass scales at all redshifts. Alternatively, static physical separation selections applied equivalently to all galaxy pairs at all redshifts lead to a difference in merger rate of up to ∼1 Gyr between low- and high-mass pairs, particularly for r
sep < 150 kpc. As a result, applying the same merger timescales to physical-separation-selected pairs will lead to a bias that systematically overpredicts low-mass galaxy merger rates.