bluuebunny/crossref_metadata_2025 huggingface dataset:
Alternative Fuel Mixture Waste Cooking Oil (WCO) and Corn Oil: Transforming Hazard into Renewable Energy
Authors: Suardi Suardi , Pawara Muhammad Uswah , Setiawan Wira , Mahmuddin Faisal , Klara Syerly
Published: October 2024

This study investigated the potential of an alternative fuel mixture comprised of Waste Cooking Oil (WCO) and Corn Oil to convert hazardous waste into a renewable energy source. Converting WCO into renewable energy had the potential to enhance energy security and reduce dependence on increasingly expensive hydrocarbon fuels, which were rising in price. The research conducted a comprehensive analysis of the effects of blending WCO biodiesel with corn oil on engine performance and emissions. The research methodology included two primary components: the transesterification process for biodiesel production and experimental test of biodiesel in diesel engines to evaluate performance and emissions. Data collected during engine operation, such as wattage, RPM, electric current, voltage, time duration, and fuel consumption, were used to calculate torque, specific fuel consumption, and engine thermal efficiency. Additionally, emissions tests were carried out, with a focus on variations in biodiesel samples. The research findings revealed that biodiesel samples containing 50% WCO (B50) exhibited significantly improved specific fuel consumption (SFC) at 678.1 g/kWh, compared to pure diesel (B0) at 852.4 g/kWh, resulting in a saving of 175.3 g/kWh. Furthermore, B50 demonstrated a higher torque output, measuring 3.69 N.m, compared to 3.35 N.m for B0, indicating a 0.34 N.m increase in torque for B50. Moreover, B50 achieved a thermal efficiency 22% higher than that of B0, reaching 22% compared to 20%. In terms of exhaust emissions, B50 displayed a significantly lower concentration (N) of 50.5% compared to B0, which recorded an (N) Value of 98.3%. this research provides valuable insights into the utilization of WCO waste for biodiesel production, offering an environmentally friendly alternative that matches or even surpasses the performance of traditional hydrocarbon fuels. It underscores the potential of WCO and corn oil blends as a sustainable energy source, with notable benefits in efficiency and emissions reduction.
Relationship between Viscosity and Surface Tension as a Solution to Fractional Differential Equations
Authors: Rusyaman Endang , Parmikanti Kankan , Chaerani Diah , Johansyah Muhamad Deni , Permana Muhammad Yorga
Published: October 2024

Viscosity, also known as thickness, is the measure of a fluid's resistance to the stress it experiences, caused by cohesive forces between fluid particles. Surface tension is the force or downward pull caused by unbalanced attractive forces at the liquid interface, leading to the contraction of the liquid surface. Numerous studies have been conducted, particularly on determining the relationship between these two phenomena. However, very few studies are associated with fractional differential equations. This paper presents research results based on empirical data obtained from laboratory testing on viscosity and surface tension and explores their interrelationship. Through scatter plot data and regression of logarithmic functions, the obtained function is claimed as a solution to a first-order linear differential equation, with the graph of its solution matching the actual data. Subsequently, this differential equation will be generalized into a fractional differential equation with guaranteed existence and uniqueness of solutions. The method used to find solutions is the Adomian-Laplace Decomposition, and the result is that the graph of the solution function coincides with the graph of the exact solution. This indicates that the relationship between viscosity and surface tension can be described using a solution derived from a fractional differential equation model.
Optimization of Upstream Natural Gas Compression Processes based on Sensitivity Analysis of Gas Throughput
Authors: Fakhrizal Fahmi Muhammad , Handogo Renanto , Purwo Sutikno Juwari , Panca Anugraha Rendra , Arifin Rizal
Published: October 2024

As the global population increases, there is a corresponding increase in the energy demand. Most of the energy consumption still comes from the use of fossil fuels. Natural gas, a fossil fuel in gaseous form, serves as a primary component in the shift towards renewable energy, making its use imperative for society. At present, transportation and high energy consumption pose significant challenges to natural gas production. Non-optimal design and operating variables lead to irreversible processes, thereby generating energy waste so that process evaluation is needed as the first stage in optimizing the process. Sensitivity analysis can be used in optimization which leads to evaluation activities that involve achieving optimal results under certain conditions. This research seeks to evaluate the effect of changes in natural gas pressure and flow rate on operational units, especially on compressors, to obtain a comparative analysis of which variables have great significance in the natural gas compression process. This evaluation study was simulated using Aspen Plus V.12 on the compressors. From the study that has been conducted, the largest net profit in the sensitivity analysis of the flow rate and pressure variables is found in the +80% change in flow rate and pressure from the Base Case, which is USD 1069.2 per hour. Then, to observe the significance of flow rate and pressure variables on net profit, it is found that changes in flow rate have a more significant effect on net profit than changes in pressure. This research can be useful as a guide to conduct a simple economic analysis by making changes to several parameters that have a significant impact and can be done as an optimization of the natural gas compression process.
Salários mais elevados: quem são, onde estão e o que fazem os que ocupam o topo da pirâmide salarial no norte de Minas
Authors: Reis Bruna Silva , Sobral Karen Jaqueline Barbosa Vieira , Martins Karine Ribeiro
Published: October 2024

Introdução: A remuneração é essencial para a sobrevivência dos trabalhadores, mas apresenta grandes disparidades, com a maioria recebendo valores mínimos e poucos obtendo salários mais elevados. Objetivo: Analisar a disparidade dos grandes salários na rede privada da região norte de Minas Gerais, visando traçar o perfil dos empregados e das organizações que pagam remunerações superiores a 20 salários-mínimos. Método: Foi utilizando dados secundários de 2022 da Base RAIS/MTE, foram examinadas as médias salariais em diferentes estados brasileiros, mesorregiões de Minas Gerais e microrregiões do Norte de Minas Gerais. Resultados: O Distrito Federal, São Paulo e Rio de Janeiro lideraram as maiores remunerações médias no Brasil, enquanto a Mesorregião Metropolitana de Belo Horizonte, Triângulo Mineiro/Alto Paranaíba e Noroeste de Minas Gerais se destacaram no estado de Minas Gerais. Quanto as microrregiões do Norte de Minas Gerais, Pirapora, Janaúba e Montes Claros apresentaram os salários mais altos. Conclusões: As organizações que pagaram esses altos salários na mesorregião do Norte de Minas não são necessariamente as empresas de grande porte. Quanto ao perfil dos trabalhadores, observou-se que a maioria eram homens, embora as mulheres tenham uma remuneração média maior do que a dos homens. E foi identificada uma correlação positiva entre o nível de escolaridade e a remuneração, com quase metade dos profissionais possuindo ensino superior. Foi possível perceber a necessidade de políticas públicas e empresariais que abordassem essas desigualdades salariais.
The Role of Caregivers in the Stroke Patients Recovery: A Mixed Methodology Study Focusing on Caregiver Challenges and Patient Outcomes
Authors: Tomar Tapasya , Vyas Mamta
Published: October 2024

Overview Patient Caregivers play a very essential role in the recovery of stroke patients, particularly among older individuals, they often require more intensive physical, emotional, and social support. one of the leading causes of long-term disability in older adults is stroke, it significantly shows impacts not only the patients but also the caregivers who help them through their rehabilitation journey. This research explores the critical role that caregivers play in post-stroke recovery for patient, with a particular focus on the challenges they face and affect the recovery outcomes of stroke patients. Given the increased burden on caregivers due to age- related complexities, this research put emphasizes on the importance of understanding the caregiver experience to improve both patient and caregiver well-being.  Methodology In This research, mixed-methods approach was used to gain a comprehensive understanding of the patient’s caregiver’s role and its impact on stroke recovery of patient. Qualitative data were gathered through semi-structured interviews with caregivers of older stroke patients (aged 60 and above). The interviews focused on the caregivers’ experiences, coping strategies, challenges, and their perceptions of how these experiences affected the patient’s recovery during rehabilitation journey. Thematic analysis was applied to identify recurring themes and patterns in the qualitative data. Quantitative data were also collected from medical records and recovery assessments of stroke patients, measuring consequence such as mobility, cognitive improvement, and overall quality of life post-stroke. The integration of qualitative insights with quantitative data provided a more holistic view of the caregiver-patient vitals.  Key Findings The study has several key challenges faced by caregivers, which substantial impacted both their well- being and the recovery of the patients. The primary challenges were:  Physical Fatigue: Many caregivers, particularly those who were older themselves, faced physical strain in assisting with daily activities such as lifting, mobility support, and personal hygiene care, leading to their own health problems.  Emotional and Mental Health Strain: Caregivers reported feelings of anxiety, depression, and emotional exhaustion. These mental health challenges often resulted in reduced patience and focus, which negatively affected the quality of care provided.  Lack of Social Support: Isolation and a lack of external support systems, such as respite care or community resources, left many caregivers feeling overwhelmed. This often led to burnout, further exacerbating the challenges faced in managing the rehabilitation process.
Hyperuricemia in Plantar Fasciitis- Attributable Cause or Associated Factor?
Authors: Shreyas N , Kumar Shetty Sanath , K Sreedhish , Saraff Rashika , Sambhavi AR Deeppika , Arun Sanjana
Published: October 2024

Pain at the heel affects millions of people globally. The burden of this entity can be virtually visualised by the fact that around 7% of people over 65 years of age report heel pain and tenderness, the main differential diagnosis being plantar fasciitis, amongst others. Plantar fasciitis is one of the most common causes of pain around the heel and plantar aspect of the foot. 80% of patients with heel pain are suffering from plantar fasciitis. Plantar fasciitis has been linked to many mechanical abnormalities and biochemical derangements. The most common biochemical derangement in patients with plantar fasciitis is increased serum uric acid levels. There is increasing evidence that presence of asymptomatic hyperuricemia is a potential risk factor for development of plantar fasciitis. The mean serum uric acid levels in the patients with plantar fasciitis was 7.02 mg/dl, which is in close proximity to the upper limit of normal uric acid levels. Also, the same was true for males and females independently. Even though majority of patients with plantar fasciitis accounting to 52% had serum uric acid levels between 6-8 mg/dl, close to the upper limit of normal value, it cannot be categorised as hyperuricemia. By virtue of this study, we can infer that hyperuricemia per se, cannot be an attributable cause of plantar fasciitis, even though it is known to play an important role in pathogenesis of calcaneal plantar spur formation, which might lead to or augment the pre existing plantar fasciitis.
A Study of Consumer Awareness Towards Green Food Products in Chennai City
Authors: Drison Maradon , Susidharan S.
Published: October 2024

Industrial activities have had a devastating impact on the environment over the years, leading to severe ecological damage. This has resulted in a significant shift in consumer behavior, with customers now prioritizing sustainability and eco-friendliness when making purchases, forcing businesses to adapt their marketing strategies accordingly. Promoting sustainable economic growth is expected to be driven by green development, fueled by consumer demand for eco- friendly products and services. This phenomenon is called 'green consumerism, where consumers seek out goods and services created with environmentally sustainable practices, including recycling and resource conservation, to reduce their environmental footprint. The study was done with 30 participants who were randomly chosen from City for the study. This research investigates consumer behavior and decision-making processes regarding environmentally friendly products, predicated on the understanding that individual consumer choices are intimately tied to environmental degradation. The study recognizes that consumer behavior is a significant contributor to environmental problems, and without significant changes, current consumption patterns pose a profound threat to the environment and society at large in the long term.
Influence of Geological Structures in Aiding Landslide Initiation in Chimanimani, Zimbabwe
Authors: Munashe Nyandoro Liberty , Lydia Meck Maideyi , Bornwell Mupaya Fadzanai
Published: October 2024

In March 2019, the Southeastern part of the Zimbabwe craton, Chimanimani, experienced a landslide that resulted in at least 350 deaths. There is considerable work currently ongoing in Chimanimani by researchers and experts to understand the landslides and prevent or minimise future damage. The objective of this study was to meticulously examine the role of geological structures in precipitating landslides using the Chimanimani district as a case study area. Comprehensive fieldwork encompassing site inspections, detailed structural mapping, petrographic analysis, and geotechnical assessments of outcrops was undertaken. The findings revealed that the region had experienced multiple deformation episodes, leading to its classification into three principal strain zones. These zones showed a positive correlation with historical and current landslide occurrences. It was noted that micro-faults were emerging progressively across various rock types. Both macroscopic and microscopic faults, along with joint systems, were identified as pivotal factors in both the onset and advancement of landslides. The majority of landslides were found on slopes with a concave upward geometry where fault planes inclined towards the slope's base. The orientation, continuity, and type of minerals filling the joints were also found to significantly influence landslide activity in Chimanimani. The presence of clay within micro-faults or joints was hypothesized to exacerbate fracture expansion due to its swelling properties upon moisture absorption. The study concluded that areas exhibiting a fault density exceeding 0.8km/km2 were highly susceptible to landslide events.
Automated Vial and Pre-Filled Syringe Counting in the Pharmaceutical Industry Using YOLO and SAHI Techniques
Authors: Kumar Sridharan Ram , Xhafa Anisa , Chaodhari Samruddhi , Putsala Sreekanth
Published: October 2024

In the pharmaceutical industry, manual counting of vials and pre-filled syringes (PFS) is a time- consuming process prone to human error, which can lead to inventory discrepancies and operational inefficiencies. This research addresses these challenges by automating the counting process using state-of-the-art deep learning techniques. We employ the YOLO (You Only Look Once) architecture from the Ultralytics library, renowned for its real-time object detection capabilities. Our study compares three versions of the YOLO models (v8, v9, v10) to determine the most accurate and efficient model for this application and designed to handle both images and videos. In this study, we applied the Slicing Algorithms for Hyper Inference (SAHI) technique to enhance object detection by efficiently handling smaller objects within larger images, thereby aiming to improve the overall accuracy and robustness of the model. However, our experimental results did not show a significant improvement over existing methods which highlights the potential limitations of the SAHI technique in certain contexts, suggesting the need for further investigation into its effectiveness and adaptability across diverse applications. Using more than 6000 images, the model were trained with a result of high mean average precision of 0.969 showcasing their high detection precision. With a counting accuracy of more than 95%, the proposed model offers an effective solution by eliminating the need for manual counting, thus reducing the potential for human error inherent in traditional methods. Additionally, the developed system seamlessly integrates the counting values with existing inventory management platforms, ensuring up-to-date stock levels and enhancing inventory accuracy. This integration offers substantial time and cost savings for the pharmaceutical and healthcare industries.
Debilitamiento de la vigilancia a las flotas calamareras de aguas distantes que usan puertos y astilleros peruanos
Authors: Miranda Eyzaguirre Alfonso , Rojas Vasquez Piero , Chavarría Bernal , Gómez Oré Iván , Gozzer-Wuest Renato
Published: October 2024

Ante la creciente amenaza global de la pesca ilegal, no declarada y no reglamentada (INDNR), en el año 2020, el gobierno peruano promulgó el Decreto Supremo Nº 016-2020-PRODUCE, que modificó el Decreto Supremo Nº 016-2016-PRODUCE con la finalidad de mejorar la vigilancia de las flotas pesqueras extranjeras de aguas distantes que desearan ingresar a puertos y astilleros peruanos. En esencia, se estableció la obligatoriedad del uso del Sistema de Seguimiento Satelital del Estado peruano (SISESAT) por parte de las flotas extranjeras de aguas distantes dedicadas al calamar gigante. El impacto sobre la operatividad de éstas fue inmediato: optaron por no instalar los dispositivos satelitales, por lo que quedaron imposibilitadas de utilizar servicios portuarios y de mantenimiento en Perú. Éstas pasaron de realizar un promedio de 265 ingresos anuales en el periodo 2016-2019, a solo 20 en los primeros dos años de aplicación de la norma (i.e., 2021-2022). Extraordinariamente, a pesar de seguir sin instalar los dispositivos satelitales, en el año 2023, el gobierno peruano autorizó el ingreso de 162 embarcaciones considerando que los motivos de sus ingresos, i.e., el cambio de tripulantes y la renovación de certificados, súbitamente pasaron a la condición de exentos del ámbito de aplicación de la norma. Ello demostró la existencia de vulnerabilidades en el sistema de monitoreo, control y vigilancia del mar peruano. No obstante, un análisis sistémico, ratio legis e histórico del citado decreto sugiere claramente que éste es de aplicación general y no admite excepciones discrecionales. Como resultado, el cambio de criterio estaría generando un escenario desfavorable para el combate contra la pesca INDNR y un debilitamiento de la posición vanguardista del Estado peruano en la protección de sus ecosistemas marinos. El artículo demuestra que una correcta aplicación de la norma requeriría eliminar las interpretaciones debilitantes, enmendando con ello lo actuado en 2023.
Justicia y seguridad en las Naciones Unidas: entre política y derecho internacional
Authors: Horna Chicchón Angel Valjean
Published: October 2024

El artículo presenta algunas interacciones entre política y derecho internacional, tomando como base una perspectiva del derecho internacional como proceso de decisiones en foros apropiados (New Haven School), en particular la ONU y sus principales órganos (la Asamblea General y el Consejo de Seguridad. Luego de plantear rasgos de la relación entre el derecho internacional y la política en el ámbito del desarrollo progresivo del derecho internacional y su codificación, el artículo elabora algunas ideas a través de dos partes principales: la justicia penal internacional y la seguridad colectiva. En cuanto a la justicia penal internacional, si bien existen mecanismos para garantizarla y reforzarla como una respuesta al ejercicio abusivo del poder y la fuerza, cuestiones políticas inevitablemente afectan los esfuerzos de la comunidad internacional. Acerca del sistema de seguridad colectiva, se pone en evidencia la crisis por la que atraviesa debido a las divisiones geopolíticas y desconfianza entre algunos de los miembros permanentes del Consejo de Seguridad. El autor concluye en que sin perjuicio de las amenazas al multilateralismo ya pesar de la instrumentalización del derecho internacional, su defensa y vigencia son trascendentales para lograr los equilibrios necesarios en el actual escenario de fragmentación y posible transición a un nuevo orden mundial, con base en un sistema más inclusivo, equitativo y representativo.
Hybridising governance for resilience in a time of crisis: learning from community-based organisations in Cape Town and Cali
Authors: Anciano Fiona , Lombard Melanie
Published: October 2024

Through the lens of food security this paper explores how community-based organisations (CBOs) in low-income neighbourhoods in Cape Town (South Africa) and Cali (Colombia) responded to the COVID-19 pandemic. In understanding how they engaged with and operationalised governance in times of crisis, we are able to critically engage with hybrid governance practices in these contexts and explore their potential to support equitable resilience. The findings are based on 12 months of qualitative research in both cities, including interviews and focus groups with community leaders and weekly digital diaries with local residents. We show how CBOs were able to supplement the state, build partnerships through boundary spanning and act as mediators and brokers by leveraging their trust-based networks to support distributive, procedural and recognitional resilience in their neighbourhoods. We argue that in contexts of vulnerability and rapidly changing conditions, hybridising governance is a more appropriate way to understand these processes, which may result in contested rather than integrated outcomes. Moreover, we find that while CBOs are highly effective first responders in times of crisis, without effective state partnership – in other words, hybridity that includes the state – their potential for longer-term systemic, equitable resilience remains limited.
Tools, Troops or Escapees? Cattle Trafficking in the Early Years of the Colony of New South Wales, Australia
Authors: PROBYN-RAPSEY FIONA , RUSSELL LYNETTE
Published: October 2024

The colonisation of ‘Australia’ by the British began in earnest with the arrival of the First Fleet in January 1788 in Warrane (Sydney Cove), to establish a penal colony on the lands of the Gadigal. The Fleet consisted of eleven ships, over 1,000 Europeans (mostly convicts) and many hundreds of animals collectively referred to as ‘cattle’: pigs, goats, sheep, horses, poultry, and cows, calves and bulls. Many of the ‘cattle’ were purchased at the Cape of Good Hope (Cape Town) in November 1787 and transported onboard the ship
Sirius
. They were intended as a population base for animal agriculture in the new colony, and part of a process that Alfred Crosby refers to as ‘ecological imperialism’, a framing, we argue, that has led to a misrepresentation of livestock animals as co-colonising accomplices and tools of colonialism. Through a close reading of the ‘wild cattle’ escapees of the early New South Wales colony, and foregrounding accounts of Indigenous people’s encounters with them, we highlight the significance of the cattle’s desire for escape, arguing that it is more apt to understand
pastoralism
as colonialism’s tool and not the animals trafficked by it. This shift in focus, we argue, draws attention to the non-neutrality of (ongoing) pastoralism as a colonial practice and provides more solid ground for acknowledging animal agency and autonomy, including from historiographic framings that situate them as mere tools, troops or weapons in two-sided colonial violence.
Spatial heterogeneity and interaction effect of urban blue and green spaces on housing prices
Authors: Chen Huilin , Hu Lihui , Liu Ziyi , Chen Bo
Published: October 2024

Rapid urbanization presents policymakers and planners with the challenge of balancing public open spaces design with the conservation and improvement of natural resources. A comprehensive understanding of the land economic value of urban blue-green spaces (UBGS) holds immense significance for urban sustainable development, urban spatial justice and the promotion of human well-being. In this study, the MGWR model is employed to discuss the heterogeneous effects of UBGS on housing prices in Hangzhou. Additionally, the interaction effect between blue space and green space was examined at the district level, and the specific locations and spatial patterns were identified. The results show that (1) different types, features and accessibility of UBGS have different degrees and spatial scale of effect on housing prices, and will be affected by other attributes of UBGS; (2) in 30.92% of the main urban area of Hangzhou, the effect of blue spaces and green spaces on housing prices exhibits an interactive effect. The spatial patterns are divided into blue-green positive synergistic, antagonistic and negative synergistic regions; (3) green space has positive and negative effects on housing prices, while blue space has positive effects on housing prices at the regional level. The existence of water bodies can promote the positive effect of green spaces on housing prices or alleviate the negative effect. The results indicate that planners must transcend the singular focus on blue or green space planning and instead consider both in an integrated manner. This outcome can provide valuable references for UBGS planning.
All Puffed Up: Exploring Ultra-diffuse Galaxy Origins Through Galaxy Interactions
Authors: Fielder Catherine , Jones Michael G. , Sand David J. , Bennet Paul , Crnojević Denija , Karunakaran Ananthan , Mutlu-Pakdil Burçin , Spekkens Kristine
Published: October 2024

We present new follow-up observations of two ultra-diffuse galaxies (UDGs) selected for their distorted morphologies and tidal features, suggestive of tidal influence. Using Hubble Space Telescope Advanced Camera for Surveys F555W and F814W imaging, we identify 8 ± 2 globular clusters in KUG 0203-Dw1 and 6 ± 2 in KDG 013, abundances typical for normal dwarf galaxies of similar stellar mass. Jansky Very Large Array data reveal a clear H i detection of KUG 0203-Dw1 with a gas mass estimate of

log

M

H

I

/

M
⊙

≲
7.4

and evidence of active stripping by the host, while KDG 013 has no clear gas detection. The UDGs likely originated as normal dwarf galaxies that have been subjected to significant stripping and tidal heating, causing them to become more diffuse. These two UDGs complete a sample of five exhibiting tidal features in the full Canada–France–Hawaii Telescope Legacy Survey area (∼1502 deg). These tidally influenced UDGs exhibit diverse properties; one stands out as a potential result of a dwarf merger, while the remainder suggest tidal heating origins. We also cannot conclusively rule out that these galaxies became UDGs in the field before processing by the group environment, underscoring the need for broader searches of diffuse galaxies to better understand the impact of galaxy interactions.
Search for Young Stellar Objects within 4XMM-DR13 Using CatBoost and SPE
Authors: Ma Xiangyao , Zhang Yanxia , Zhang Jingyi , Li Changhua , Kang Zihan , Li Ji
Published: October 2024

Classifying and summarizing large data sets from different sky survey projects is essential for various subsequent scientific research. By combining data from 4XMM-DR13, Sloan Digital Sky Survey (SDSS) DR18, and CatWISE, we formed an XMM-WISE-SDSS sample that included information in the X-ray, optical, and infrared bands. By cross matching this sample with data sets from known spectral classifications from SDSS and LAMOST, we obtained a training data set containing stars, galaxies, quasars, and young stellar objects (YSOs). Two machine learning methods, CatBoost and Self-Paced Ensemble (SPE), were used to train and construct machine learning models through training sets to classify the XMM-WISE-SDSS sample. Notably, the SPE classifier showed excellent performance in YSO classification, identifying 1102 YSO candidates from 160,545 sources, including 258 known YSOs. Then we further verify whether these candidates are YSOs by the spectra in LAMOST and the identification in the SIMBAD and VizieR databases. Finally there are 412 unidentified YSO candidates. The discovery of these new YSOs is an important addition to existing YSO samples and will deepen our understanding of star formation and evolution. Moreover we provided a classification catalog for the whole XMM-WISE-SDSS sample.
AGN STORM 2. VII. A Frequency-resolved Map of the Accretion Disk in Mrk 817: Simultaneous X-Ray Reverberation and UVOIR Disk Reprocessing Time Lags
Authors: Lewin Collin , Kara Erin , Barth Aaron J. , Cackett Edward M. , De Rosa Gisella , Homayouni Yasaman , Horne Keith , Kriss Gerard A. , Landt Hermine , Gelbord Jonathan , Montano John , Arav Nahum , Bentz Misty C. , Boizelle Benjamin D. , Dalla Bontà Elena , Brotherton Michael S. , Dehghanian Maryam , Ferland Gary J. , Fian Carina , Goad Michael R. , Hernández Santisteban Juan V. , Ilić Dragana , Kaastra Jelle , Kaspi Shai , Korista Kirk T. , Kosec Peter , Kovačević Andjelka , Mehdipour Missagh , Miller Jake A. , Netzer Hagai , Neustadt Jack M. M. , Panagiotou Christos , Partington Ethan R. , Č. Popović Luka , Sanmartim David , Vestergaard Marianne , Ward Martin J. , Zaidouni Fatima
Published: October 2024

X-ray reverberation mapping is a powerful technique for probing the innermost accretion disk, whereas continuum reverberation mapping in the UV, optical, and infrared (UVOIR) reveals reprocessing by the rest of the accretion disk and broad-line region (BLR). We present the time lags of Mrk 817 as a function of temporal frequency measured from 14 months of high-cadence monitoring from Swift and ground-based telescopes, in addition to an XMM-Newton observation, as part of the AGN STORM 2 campaign. The XMM-Newton lags reveal the first detection of a soft lag in this source, consistent with reverberation from the innermost accretion flow. These results mark the first simultaneous measurement of X-ray reverberation and UVOIR disk reprocessing lags—effectively allowing us to map the entire accretion disk surrounding the black hole. Similar to previous continuum reverberation mapping campaigns, the UVOIR time lags arising at low temporal frequencies are longer than those expected from standard disk reprocessing by a factor of 2–3. The lags agree with the anticipated disk reverberation lags when isolating short-timescale variability, namely timescales shorter than the Hβ lag. Modeling the lags requires additional reprocessing constrained at a radius consistent with the BLR size scale inferred from contemporaneous Hβ-lag measurements. When we divide the campaign light curves, the UVOIR lags show substantial variations, with longer lags measured when obscuration from an ionized outflow is greatest. We suggest that, when the obscurer is strongest, reprocessing by the BLR elongates the lags most significantly. As the wind weakens, the lags are dominated by shorter accretion disk lags.
Measurements of Magnetic Cloud Expansion through Multiple Spacecraft in Radial Conjunction
Authors: Yu Wenyuan , Al-Haddad Nada , Farrugia Charles J. , Lugaz Noé , Zhuang Bin , Regnault Florian , Galvin Antoinette B.
Published: October 2024

The aim of this study is to use multispacecraft measurements of interplanetary magnetic clouds (MCs) to better constrain and understand the effect of expansion on their magnetic field properties. We develop a parameter (γ) for comparing magnetic field components measured at multiple spacecraft. We use the minimum variance technique on the magnetic field data to obtain the axial and azimuthal components. The parameter γ acts at the front boundary as a measure of the global difference in the evolution with heliospheric distance of the axial and azimuthal magnetic field components of MCs. Our goal is to determine whether the studied MCs exhibit self-similar expansion and, if so, whether this expansion is predominantly isotropic or radial, based on the estimated γ. Through our analysis of data from multiple spacecraft, we observe a notable consistency in the γ values across the examples examined. We find that the overall expansion of these MCs tends to be isotropic, while the local expansion of MCs, derived from the γ values measured at the rear boundary of MCs, usually shows anisotropic behavior, particularly when the distances between the observations from the two spacecraft are relatively short. This discovery offers insights for refining flux rope models and advancing our comprehension of the expansion processes associated with coronal mass ejections.
Optical Continuum Reverberation Mapping of a Candidate IMBH in a Nearby Seyfert 1 Galaxy
Authors: Zuo Wenwen , Guo Hengxiao , Sun Jingbo , Yuan Qi , Lira Paulina , Gu Minfeng , Edwards Philip G. , Gupta Alok C. , Kishore Shubham , Stevens Jamie , An Tao , Cai Zhen-Yi , Feng Hai-Cheng , Ho Luis C. , Ilić Dragana , Kovačević Andjelka B. , Li Sha-Sha , Mezcua Mar , Č. Popović Luka , Sun Mouyuan , Tripathi Tushar , U Vivian , Vince Oliver , Wang Jianguo , Wang Junxian , Wang Shu , Wu Xuebing , Zheng Zhenya
Published: October 2024

To investigate the short-term variability and determine the size of the optical continuum emitting region of intermediate-mass black holes (IMBHs), we carried out high-cadence, multiband photometric monitoring of a Seyfert 1 galaxy J0249−0815 across two nights, together with a one-night single-band preliminary test. The presence of the broad Hα component in our target was confirmed by recent Palomar/P200 spectroscopic observations, 23 yr after the Sloan Digital Sky Survey, ruling out the supernovae origin of the broad Hα line. The photometric experiment was primarily conducted utilizing four-channel imagers MuSCAT 3 and 4 mounted on 2 m telescopes within the Las Cumbres Observatory Global Telescope Network. Despite the expectation of variability, we observed no significant variation (<1.4%) on timescales of 6–10 hr. This nondetection is likely due to substantial host galaxy light diluting the subtle active galactic nucleus (AGN) variability. Additionally, we cannot rule out that the target was in a relatively quiescent state without intranight variability during our monitoring, owing to the stochastic nature of AGN variations. To enhance the possibility of detecting subtle variability signals and lag in future IMBH reverberation campaigns, it may be beneficial to select targets with a higher AGN-to-host flux ratio, and conduct dual-band preliminary tests and tailored simulations.
Toward Accelerated Nuclear-physics Parameter Estimation from Binary Neutron Star Mergers: Emulators for the Tolman–Oppenheimer–Volkoff Equations
Authors: Reed Brendan T. , Somasundaram Rahul , De Soumi , Armstrong Cassandra L. , Giuliani Pablo , Capano Collin , Brown Duncan A. , Tews Ingo
Published: October 2024

Gravitational-wave observations of binary neutron-star (BNS) mergers have the potential to revolutionize our understanding of the nuclear equation of state (EOS) and the fundamental interactions that determine its properties. However, Bayesian parameter estimation frameworks do not typically sample over microscopic nuclear-physics parameters that determine the EOS. One of the major hurdles in doing so is the computational cost involved in solving the neutron-star structure equations, known as the Tolman–Oppenheimer–Volkoff (TOV) equations. In this paper, we explore approaches to emulating solutions for the TOV equations: multilayer perceptrons (MLPs), Gaussian processes, and a data-driven variant of the reduced basis method (RBM). We implement these emulators for three different parameterizations of the nuclear EOS, each with a different degree of complexity represented by the number of model parameters. We find that our MLP-based emulators are generally more accurate than the other two algorithms, whereas the RBM results in the largest speedup with respect to the full high-fidelity TOV solver. We employ these emulators for a simple parameter inference using a potentially loud BNS observation and show that the posteriors predicted by our emulators are in excellent agreement with those obtained from the full TOV solver.
A Millimeter Rebrightening in GRB 210702A
Authors: de Wet Simon , Laskar Tanmoy , Groot Paul J. , Barniol Duran Rodolfo , Berger Edo , Bhandari Shivani , Eftekhari Tarraneh , Guidorzi Cristiano , Kobayashi Shiho , Perley Daniel A. , Sari Re’em , Schroeder Genevieve
Published: October 2024

We present X-ray to radio frequency observations of the bright long gamma-ray burst GRB 210702A. Our Atacama Large Millimeter/submillimeter Array 97.5 GHz observations show a significant rebrightening by a factor of ≈2 beginning at 8.2 days post-burst and rising to peak brightness at 18.1 days before declining again. This is the first such rebrightening seen in a millimeter afterglow light curve. A standard forward shock model in a stellar wind circumburst medium can explain most of our X-ray, optical, and millimeter observations prior to the rebrightening, but significantly overpredicts the self-absorbed radio emission, and cannot explain the millimeter rebrightening. We investigate possible explanations for the millimeter rebrightening, and find that energy injection or a reverse shock from a late-time shell collision are plausible causes. Similar to other bursts, our radio data may require alternative scenarios such as a thermal electron population or a structured jet to explain the data. Our observations demonstrate that millimeter light curves can exhibit some of the rich features more commonly seen in optical and X-ray afterglow light curves, motivating further millimeter wavelength studies of GRB afterglows.
Five New Heartbeat Star Systems with Tidally Excited Oscillations Discovered Based on TESS Data
Authors: Li Min-Yu , Qian Sheng-Bang , Zhou Ai-Ying , Zhu Li-Ying , Liao Wen-Ping , Zhao Er-Gang , Shi Xiang-Dong , Li Fu-Xing , Sun Qi-Bin
Published: October 2024

Heartbeat stars (HBSs) with tidally excited oscillations (TEOs) are ideal astrophysical laboratories for studying the internal properties of the systems. In this paper, five new HBSs exhibiting TEOs are discovered using TESS photometric data. The orbital parameters are derived using a corrected version of Kumar et al.'s model based on the Markov Chain Monte Carlo method. The TEOs in these objects are examined, and their pulsation phases and modes are identified. The pulsation phases of the TEOs in TIC 266809405, TIC 266894805, and TIC 412881444 are consistent with the dominant l = 2, m = 0, or ±2 spherical harmonic. For TIC 11619404, although the TEO phase is close to the m = +2 mode, the m = 0 mode cannot be excluded because of the low inclination in this system. The TEO phase in TIC 447927324 shows a large deviation (>2σ) from the adiabatic expectations, suggesting that it is expected to be a traveling wave or that the pulsations are nonadiabatic. In addition, these TEOs occur at relatively low orbital harmonics, and we cautiously suggest that this may be an observational bias. These objects are valuable sources for studying the structure and evolution of eccentricity orbit binaries and extending the TESS HBS catalog with TEOs.
Contribution of the Cygnus Bubble to the Galactic Cosmic Ray Spectrum and Diffuse γ-Ray Emissions
Authors: Nie Lin , Qian Xiang-Li , Guo Yi-Qing , Liu Si-Ming
Published: October 2024

Since the discovery of cosmic rays (CRs) over a century ago, their origin has remained a mystery and a key research question. Recently, the LHAASO experiment identified the first CR superacceleration source, the Cygnus bubble, which can accelerate CRs to energies exceeding 10 PeV. A pertinent question is how much the Cygnus bubble contributes to the CR spectrum observed on Earth. With the aim of answering that question, a 3D propagation analysis was conducted on CRs in this study. The Cygnus bubble was incorporated into our propagation model in order to determine its contributions to the observed spectra. First, we calculated the spectrum and spatial morphology of the Cygnus bubble to reproduce the observed LHAASO data. Subsequently, we calculated the diffuse γ-ray emissions produced by the CRs from the Cygnus bubble and the energy spectrum of the CR particles near Earth after propagation. Finally, we utilized a CR spatial-dependent propagation model to calculate the large-scale CR energy spectrum and the resulting diffuse γ-ray emissions. Our results indicate that (1) the Cygnus bubble contributes minimally to the CR spectrum observed on Earth, (2) the emissions produced by the CR particles from the Cygnus bubble dominate the diffuse γ-ray emissions in that region, and (3) the structural fluctuations of the diffuse γ-ray emissions observed by LHAASO are likely due to the local CR halo. We anticipate that LHAASO will identify more CR halo sources to validate our model.
Linking High-z and Low-z: Are We Observing the Progenitors of the Milky Way with JWST?
Authors: Rusta Elka , Salvadori Stefania , Gelli Viola , Koutsouridou Ioanna , Marconi Alessandro
Published: October 2024

The recent JWST observation of the Firefly Sparkle at z = 8.3 offers a unique opportunity to link the high- and the low-z Universe. Indeed, the claim of it being a Milky Way (MW) type of assembly at the cosmic dawn opens the possibility of interpreting the observation with locally calibrated galaxy-formation models. Here, we use the a state-of-the-art MW-evolution model to perform forward modeling of our Galaxy's progenitors at high-z. We build a set of mock spectra for the MW building blocks to make predictions for JWST and to interpret the Firefly Sparkle observation. First, we find that the most massive MW progenitor becomes detectable in a deep survey like JADES from z ≈ 8.2, meaning that we could have already observed MW analogs that still need interpretation. Second, we provide predictions for the number of detectable MW progenitors in lensed surveys like the CAnadian NIRISS Unbiased Cluster Survey, and interpret the Firefly Sparkle as a group of MW building blocks. Both the number of detections and the observed NIRCam photometry are consistent with our predictions. By identifying the MW progenitors whose mock photometry best fits the data, we find bursty and extended star formation histories, lasting >150–300 Myr, and estimate their properties: M

h
≈ 108−9
M
⊙, M
⋆ ≈ 106.2−7.5
M
⊙, SFR ≈ 0.04–0.20 M
⊙ yr−1, and Z
gas ≈ 0.04–0.24 Z
⊙. Uncovering the properties of MW analogs at cosmic dawn by combining JWST observations and locally constrained models will allow us to understand our Galaxy's formation, linking the high- and low-z perspectives.
Performance in the recruitment life stage and its potential contribution to invasive success in the polyploid invader Centaurea stoebe
Authors: Kožić Kevin , Hartmann Matthias , Callaway Ragan M. , Hensen Isabell , Nagy Dávid U. , Mráz Patrik , Al-Gharaibeh Mohammad M. , Bancheva Svetlana , Diaconu Alecu , Danihelka Jiří , Ensing David J. , Filep Rita , Gudžinskas Zigmantas , Hajdari Avni , Nicoară Roxana , Lachmuth Susanne , Moffat Chandra E. , Novikov Andriy , Purger Dragica , Slate Mandy L. , Synowiec Agnieszka , Vonica Ghizela D. , Zuleger Annika M. , Rosche Christoph
Published: October 2024

The recruitment life stage, including germination and early seedling establishment, is the most vulnerable life stage of plants and has cascading effects on plant performance at later life stages. However, surprisingly little is known on the eco-evolutionary processes that determine the success of biological invasions at this life stage.

We performed germination experiments with and without simulated drought stress and monitored early seedling growth in diploid and tetraploid Centaurea stoebe. While diploids are the major cytotype in the native European range, only tetraploids became invasive in North America. Thus, C. stoebe is an excellent model species to simultaneously study both, pre-adaptive differences in the native range (diploids vs. tetraploids) and post-introduction evolution in the non-native range (native tetraploids vs. non-native tetraploids). To account for broad spatial-environmental variation within cytotypes and ranges, we germinated 23,928 seeds from 208 widely distributed populations.

Tetraploids germinated better than diploids. Within tetraploids, invasive populations outperformed native populations in germination. However, these differences were not evident under simulated drought stress. Seedlings of invasive tetraploids had a higher biomass and developed the first true leaf earlier than those from the native range, while the native cytotypes did not differ in these early seedling traits.

Our results suggest that a combination of pre-adaptation related to superior performance of polyploids (greater and faster germination) and post-introduction evolution towards higher performance in the invasive range (greater and faster germination, greater and faster accumulation of seedling biomass) may have contributed to the invasion success of tetraploid C. stoebe in North America.
La valeur de la musique
Authors: Darsel Sandrine
Published: October 2024

L’enjeu de cet article est d’établir la valeur de la musique et de répondre à la question suivante : pourquoi y a-t-il de la musique ? Il s’agira de répondre à l’objection du vide sémantique de la musique, réduisant cette dernière à un divertissement ou à un beau jeu des sensations. La musique est un langage symbolique au fonctionnement esthétique : elle est un art du temps.
La pénurie de masseurs-kinésithérapeutes en milieu thermal : quel constat et quelle(s) solution(s) ?
Authors: Dubourg Karine , Ramon Dupuy Sybille , Caffray Maxime , Dorothée Leilla , Wurth Céline , Bauduer Frédéric
Published: October 2024

Objectif : Le but de cette enquête a été d’obtenir un état des lieux quant à la pénurie de masseurs-kinésithérapeutes exerçant en établissements thermaux français et de trouver des solutions afin de pouvoir conserver une offre de soins thermaux complète. Méthodes : Nous avons créé un mini-questionnaire en ligne composé de neuf questions à partir du logiciel SurveyMonkey ® qui a été adressé à l’ensemble des 109 directeurs d’établissements thermaux français adhérents de l’unique syndicat professionnel thermal (le Conseil national des exploitants thermaux – Cneth). Résultats : Soixante-six directeurs établissements thermaux ont répondu (60 %) avec une majorité de réponses soulignant le manque de masseurs-kinésithérapeutes et son retentissement sur le soin. Près de 90 % d’entre eux proposent la création d’un diplôme intermédiaire entre l’agent thermal et le masseur-kinésithérapeute. Conclusion : La création d’un nouveau métier serait la solution à privilégier pour pallier le manque de masseurs-kinésithérapeutes en milieu thermal.