bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long-period oscillations in the lower solar atmosphere prior to flare events
Authors: Wiśniewska A. , Korsós M. B. , Kontogiannis I. , Soós Sz. , Erdélyi R. 
Published: April 2024

Context. Multiple studies have identified a range of oscillation periods in active regions, from 3−5 min to long-period oscillations that last from tens of minutes to several hours. Recently, it was also suggested that these periods are connected with eruptive activity in the active regions. Thus, it is essential to understand the relation between oscillations in solar active regions and their solar eruption activity.
Aims. We investigate the long-period oscillations of NOAA 12353 prior to a series of C-class flares and correlate the findings with the 3- to 5-min oscillations that were previously studied in the same active region. The objective of this work is to elucidate the presence of various oscillations with long periods in the lower solar atmosphere both before and after the flare events.
Methods. To detect long-period oscillations, we assessed the emergence, shearing, and total magnetic helicity flux components from the photosphere to the top of the chromosphere. To analyze the magnetic helicity flux in the lower solar atmosphere, we used linear force-free field extrapolation to construct a model of the magnetic field structure of the active region. Subsequently, the location of long-period oscillations in the active region was probed by examining the spectral energy density of the measured intensity signal in the 1700 Å, 1600 Å, and 304 Å channels of the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO). Significant oscillation periods were determined by means of a wavelet analysis.
Results. Based on the evolution of the three magnetic helicity flux components, 3- to 8-h periods were found both before and after the flare events, spanning from the photosphere to the chromosphere. These 3- to 8-h periods were also evident throughout the active region in the photosphere in the 1700 Å channel. Observations of AIA 1600 Å and 304 Å channels, which cover the chromosphere to the transition region, revealed oscillations of 3−8 h near the region in which the flare occurred. The spatial distribution of the measured long-period oscillations mirror the previously reported distribution of 3- to 5-min oscillations in NOAA 12353 that were seen both before and after the flares.
Conclusions. This case study suggest that the varying oscillation properties in a solar active region could be indicative of future flaring activity.
Estimating the lateral speed of a fast shock driven by a coronal mass ejection at the location of solar radio emissions
Authors: Normo S. , Morosan D. E. , Kilpua E. K. J. , Pomoell J. 
Published: April 2024

Context. Fast coronal mass ejections (CMEs) can drive shock waves capable of accelerating electrons to high energies. These shock-accelerated electrons act as sources of electromagnetic radiation, often in the form of solar radio bursts. Recent findings suggest that radio imaging of solar radio bursts can provide a means to estimate the lateral expansion of CMEs and associated shocks in the low corona.
Aims. Our aim is to estimate the expansion speed of a CME-driven shock at the locations of radio emission using 3D reconstructions of the shock wave from multiple viewpoints.
Methods. In this study, we estimated the 3D location of radio emission using radio imaging from the Nançay Radioheliograph and the 3D location of a CME-driven shock. The 3D shock was reconstructed using white-light and extreme ultraviolet images of the CME from the Solar Terrestrial Relations Observatory, Solar Dynamics Observatory, and the Solar and Heliospheric Observatory. The lateral expansion speed of the CME-driven shock at the electron acceleration locations was then estimated using the approximate 3D locations of the radio emission on the surface of the shock.
Results. The radio bursts associated with the CME were found to reside at the flank of the expanding CME-driven shock. We identified two prominent radio sources at two different locations and found that the lateral speed of the shock was between 800 and 1000 km s−1 at these locations. Such a high speed during the early stages of the eruption already indicates the presence of a fast shock in the low corona. We also found a larger ratio between the radial and lateral expansion speed compared to values obtained higher up in the corona.
Conclusions. We estimated for the first time the 3D expansion speed of a CME-driven shock at the location of the accompanying radio emission. The high shock speed obtained is indicative of a fast acceleration during the initial stage of the eruption. This acceleration leading to lateral speeds in the range of 800−1000 km s−1 is most likely one of the key parameters contributing to the presence of metric radio emissions, such as type II radio bursts.
Formation of long-period post-common-envelope binaries
Authors: Belloni Diogo , Schreiber Matthias R. , Zorotovic Monica 
Published: April 2024

Context. The vast majority of close binaries containing a compact object, including the progenitors of supernovae Ia and at least a substantial fraction of all accreting black holes in the Galaxy, form through common-envelope (CE) evolution. Despite this importance, we struggle to even understand the energy budget of CE evolution. For decades, observed long-period post-CE binaries have been interpreted as evidence of additional energies contributing during CE evolution. We have recently shown that this argument is based on simplified assumptions for all long-period post-CE binaries containing massive white dwarfs (WDs). The only remaining post-CE binary star that has been claimed to require contributions from additional energy sources to understand its formation is KOI 3278.
Aims. Here, we address in detail the potential evolutionary history of KOI 3278. In particular, we investigate whether extra energy sources, such as recombination energy, are indeed required to explain its existence.
Methods. We used the 1D stellar evolution code MESA to carry out binary evolution simulations and searched for potential formation pathways for KOI 3278 that are able to explain its observed properties.
Results. We find that KOI 3278 can be explained if the WD progenitor filled its Roche lobe during a helium shell flash. In this case, the orbital period of KOI 3278 can be reproduced if the CE binding energy is calculated taking into account gravitational energy and thermodynamic internal energy. While the CE evolution that led to the formation of KOI 3278 must have been efficient – that is, most of the available orbital energy must have been used to unbind the CE – recombination energy is not required.
Conclusions. We conclude that currently not a single observed post-CE binary requires one to assume that energy sources other than gravitational and thermodynamic energy are contributing to CE evolution. KOI 3278, however, remains an intriguing post-CE binary as, unlike its siblings, understanding its existence requires highly efficient CE ejection.
Molecular line polarisation from the circumstellar envelopes of asymptotic giant branch stars
Authors: Vlemmings W. H. T. , Lankhaar B. , Velilla-Prieto L. 
Published: April 2024

Context. Polarisation observations of masers in the circumstellar envelopes (CSEs) around asymptotic giant branch (AGB) stars have revealed strong magnetic fields. However, masers probe only specific lines of sight through the CSE. Non-masing molecular line polarisation observations can more directly reveal the large-scale magnetic field morphology and hence probe the effect of the magnetic field on AGB mass loss and the shaping of the AGB wind.
Aims. Observations and models of CSE molecular line polarisation can now be used to describe the magnetic field morphology and estimate its strength throughout the entire CSE.
Methods. We used observations taken with the Atacama Large Millimeter/submillimeter Array (ALMA) of molecular line polarisation in the envelope of two AGB stars: CW Leo and R Leo. We modelled the observations using the multi-dimensional polarised radiative transfer tool PORTAL.
Results. We found linearly polarised emission, with maximum fractional polarisation on the order of a few percent, in several molecular lines towards both stars. Towards R Leo, we also found a high level of linear polarisation (up to ∼35%) for one of the SiO v = 1 maser transitions. We can explain the observed differences in polarisation structure between the different molecular lines by alignment of the molecules through a combination of the Goldreich-Kylafis effect and radiative alignment effects. We specifically show that the polarisation of CO traces the morphology of the magnetic field. Competition between the alignment mechanisms allowed us to describe the behaviour of the magnetic field strength as a function of the radius throughout the circumstellar envelope of CW Leo. The magnetic field strength derived using this method is inconsistent with the magnetic field strength derived using a structure-function analysis of the CO polarisation and the strength previously derived using CN Zeeman observations. In contrast with CW Leo, the magnetic field in the outer envelope of R Leo appears to be advected outwards by the stellar wind.
Conclusions. The ALMA observations and our polarised radiative transfer models show the power of using multiple molecular species to trace the magnetic field behaviour throughout the circumstellar envelope. While the observations appear to confirm the existence of a large-scale magnetic field, further observations and modelling are needed to understand the apparent inconsistency of the magnetic field strength derived with different methods in the envelope of CW Leo.
Endoscopic characteristics to differentiate SSLs and microvesicular hyperplastic polyps from goblet cell-rich hyperplastic polyps
Authors: Toyoshima Osamu , Nishizawa Toshihiro , Watanabe Hidenobu , Matsuno Tatsuya , Yoshida Shuntaro , Takahashi Yoshiyuki , Mizutani Hiroya , Ebinuma Hirotoshi , Fujishiro Mitsuhiro , Saito Yutaka 
Published: April 2024

Abstract
Background and study aims Among colorectal serrated polyps (SPs), sessile serrated lesions (SSLs) and hyperplastic polyps (HPs) have a similar endoscopic appearance. However, the endoscopic distinctions between those two categories, microvesicular HPs (MVHPs) and goblet cell-rich HPs (GCHPs), are not well understood. Therefore, we compared the endoscopic features of SSLs, MVHPs, and GCHPs.
Methods This retrospective, cross-sectional study was conducted at the Toyoshima Endoscopy Clinic. We examined polyp size, location, Paris classification type, mucus cap, indistinct border, expanded crypt opening, varicose microvascular vessels, and JNET classification type. Multivariable analysis of each endoscopic finding using a binomial logistic regression model determined the factors that predicted SP histology.
Results A total of 670 SPs were enrolled in this study, comprising 159 SSLs, 361 MVHPs, and 150 GCHPs. On comparing the SSL + MVHP group and the GCHP group, a mucus cap (partial regression coefficient 1.705), expanded crypt opening (1.828), and varicose microvascular vessels (1.270) were more often observed in the SSL + MVHP group compared with the GCHP group. In the comparison between MVHPs and GCHPs, a mucus cap (1.564), expanded crypt opening (1.802), and varicose microvascular vessels (1.288) were more often found in MVHPs in contrast to GCHPs. When comparing SSLs and MVHPs, SSLs were more likely to be in the proximal colon (0.662) and were larger (0.198) than the MVHPs. No significant differences were observed in other endoscopic findings.
Conclusions SSLs and MVHPs have endoscopic appearances that differ from those of GCHPs. Considering MVHPs and GCHPs as distinct entities may aid in endoscopic diagnosis of SPs.
Assessing the decarbonization roadmap of a RoPax ferry
Authors: Mayanti Bening , Hellström Magnus , Katumwesigye Anthony 
Published: April 2024

AbstractThe reduction of emissions from shipping is necessary to combat climate change. One viable option is to change the fuels utilized. In this study, we investigate the environmental and economic performance of marine diesel oil (MDO), liquified natural gas (LNG), liquified biogas (LBG), and a mixture of LNG and LBG. We study a real case of a roll-on/roll-off passenger ship (RoPax) in Finland. Life cycle thinking is applied to assess the environmental impact, covering emissions from well to propeller (raw material extraction, fuel production, transportation, storage, and combustion), while the economic implications are estimated through future fuel prices and carbon pricing from 2023 to 2050. The carbon pricing covers different carbon tax schemes, namely stated policies scenario (STEPS), sustainable development scenarios (SDS), and net-zero emissions (NZE). STEPS reflects the existing measures and policies under development; SDS pursues to meet the goal of Paris Agreement, while NZE aims to reach net zero. Adopting LNG would improve carbon dioxide emissions, but the overall climate change impact was not significantly lower than MDO. It is also found that the biggest environmental improvement can be obtained by switching to LBG, although future availability can be an issue. The economic assessment shows that LBG has the highest fuel price uncertainties, although its carbon cost will be the lowest. Alternatively, using LNG & LBG mixture can serve as a transition path to contain climate change while dealing with its price uncertainty and availability.
The impact of boundary spanning activities and resource orchestration in improving performance of Indonesian state-owned bank branches
Authors: Ariwibowo Aziz , Afiff Adi , Rachmawati Riani , Kusumastuti Ratih 
Published: April 2024

AbstractState-owned enterprises have responsibilities to conduct head office’s strategies to make profits, to execute public programs and obligations, to maintain their viabilities, to serve customers, and to manage employees. Those prompt their branch managers not only to explore their environment but also to face a goal conflict situation. This study is to investigate the effects of branch managers’ boundary spanning activities and resource orchestration on the performance of branch offices in the dynamics of environmental uncertainty and goal conflict. This study employs structural equation modeling on one of the most prominent state-owned banks in Indonesia, with 201 branch offices as the unit of analysis, and 186 branch managers as respondents. The results of this study show that boundary spanning activities have a positive and significant relationship with resource orchestration. Meanwhile, both boundary spanning activities and resource orchestration are to influence the performance of branch offices. However, the influence varies widely, depending on environmental uncertainty and goal conflict experienced by branch managers. Furthermore, this study delves into an interesting phenomenon, that goal conflict situation, instead of reducing boundary spanning activities, it increases them but has no impact on resource orchestration. This closely relates to the culture of Indonesia as a nation with high power distance, low individualism, low masculinity, and low indulgence which represent preferences to prioritize workplace harmony, obey supervisors, and be loyal to the workplace.
Using social network analysis to investigate mathematical connections in U.S. and Chinese textbook problems
Authors: Li Shuhui , Fan Lianghuo 
Published: April 2024

AbstractTextbooks, as potentially implemented curricula, play an important role in supporting classroom teaching and learning. Mathematical connections, one of the essential and hot topics advocated in mathematics education, have been emphasized in national curriculum reforms in various countries. However, little is known about the connection networks represented in school textbooks; even less has been done to compare textbooks from different countries. In this study, we propose an innovative method for examining how connections are represented in two popular U.S. (the UCSMP series) and Chinese (the PEP-A series) high school textbook problems involving quadratic relations. By using social network analysis, we identified 1129 connections, characterized connection networks into dense, moderate, and sparse digraphs, identified influential, prominent, and dual concepts and representations, and evaluated the strength between typical and reverse connections. The results revealed that the Chinese series presented a denser network of balanced between-concept connections but limited within-concept connections. The U.S. series exhibited more within-concept connections but emphasized typical connections, thus validating the potential of this innovative method. From this study, we suggest that our novel method provides a theoretical contribution to textbook analysis and connection analysis, which has rich implications for practice, for example, examining the network of connections students construct as a way to assess and to promote their conceptual understanding, and our approach opens the possibility of adopting new and efficient analytical tools from social network analysis in mathematics education research.
Diplocarpon coronariae (Ellis & Davis) Wöhner & Rossman
Authors: CABI  , EPPO  
Published: April 2024

Abstract

A new distribution map is provided for Diplocarpon coronariae (Ellis & Davis) Wöhner & Rossman Leotiomycetes: Helotiales: Drepanopezizaceae Host: apple (
Malus spp
.)
Neopestalotiopsis rosae Maharachch., Hyde & Crous
Authors: CABI  , EPPO  
Published: April 2024

Abstract

A new distribution map is provided for Neopestalotiopsis rosae Maharachch., Hyde & Crous Sordariomycetes: Amphisphaeriales: Pestalotiopsidaceae Hosts: many, including strawberry (Fragaria x ananassa), pecan (Caryaillinoinensis), blueberry (
Vaccinium corymbosum
)
Unveiling the cation ratio mediated structural modifications in TiO2:GeO2 mixtures for gravitational-wave detectors
Authors: Bhowmick Sangita , Osovsky Ruth , Davenport Aaron , Schiettekatte François , Chicoine Martin , Menoni Carmen S 
Published: April 2024

Abstract
Amorphous thin films of Ti doped GeO2 are of interest for coatings of the mirrors in gravitational wave detectors (GWDs) due to their low internal friction (Vajente et al 2021 Phys. Rev. Lett.
127 071101). The addition of Ti to amorphous GeO2 (a-GeO2) enables tailoring of the optical and structural properties of the mixtures. However, the specific modifications that occur in the amorphous network with the addition of Ti are not known. In this work, x-ray photoelectron spectroscopy is used to identify modifications to the bonding of Ge and Ti atoms in mixtures of Ti doped a-GeO2 with different Ti cation content. The formation of (Ti–O–Ge) bonds is evidenced from: (1) the presence of a peak which intensity increases with Ti content and causes a shift to lower binding energy (BE) of the core level O 1s peak; (2) the shift to higher BE of the Ti 2p
3/2 peak and a decrease in the energy split; and (3) the shift to lower BE of the Ge 3d
5/2 peak and increase in the energy split. These changes reflect modifications to the bonding when Ge replaces Ti in Ti–O–Ti bonds and Ti replaces Ge in Ge–O–Ge bonds due to their difference in electronegativity. A decrease in the O–O nearest-neighbour distance due to the incorporation of Ti atom is also observed from the broadening of the valence band spectra. The results show the 0.44 Ti doped a-GeO2 mixture has a balance between the (Ti–O–Ge) and the (Ge–O–Ge) networks, not observed in Ti poor and Ti rich mixtures. This finding could have important consequences in the optimisation of amorphous Ti doped a-GeO2 mixtures for low internal friction coatings of GWDs.
DFT studies of the structural and electronic properties of PdGe
n
(n = 1–11) clusters and adsorption capacity for some gas molecules
Authors: Wu Mei , Wu Shao-Yi , Zhong Si-Ying , Lei Xin-Yi , Kuang Min-Quan 
Published: April 2024

Abstract
Density functional theory calculations have been employed for the theoretical studies of the geometric structures and electronic characteristics of PdGe
n
(n = 1−11) clusters. An analysis of the second- order energy differences indicates that PdGe7 and PdGe10 clusters possess superior thermodynamic stability. PdGe10 displays the highest chemical stability and the lowest chemical activity, due to its largest energy gap value (E
g). Vertical ionization potential and vertical electron affinity exhibit the decreasing and increasing trends, respectively, with the increase of the number n of Ge atoms. PdGe10 presents the highest electronegativity among these clusters. The analysis on the adsorption properties of PdGe
n
(n = 7,10) clusters for gas molecules (e.g. CO, NO, NO2, NH3, SO2 and H2S) yields the adsorption structures, adsorption energies, Mulliken charge transfer and the changes in the electronic properties. All the listed gas molecules chemically adsorb onto PdGe7. PdGe10 has a better adsorption performance for NO2, while its adsorption ability for CO is poorer. The potentiality of PdGe
n
(n = 7, 10) clusters as gas sensors is also evaluated and reveals that NO adsorption significantly affects the electronic properties, especially conductivity, of the systems. PdGe10 has an appropriate NO adsorption capacity and significant charge transfer, with the adsorption energy of −0.278 eV and the recovery time of about 10−9s, indicating its fast response and hence good potentiality as the NO sensor. In contrast, PdGe7 has a higher adsorption capability towards NO with a lower adsorption energy of −1.16 eV, leading to the difficulty in desorption and a longer recovery time of over 12 h.
Cold atmospheric pressure plasma assisted rapid assembly of peptide-based structures: a molecular scaffold to form supramolecular architectures
Authors: Basumatary Deepjyoti , Gaikhe Arya , Radhakrishnanand P , Sankaranarayanan Kamatchi 
Published: April 2024

Abstract
The use of cold atmospheric pressure plasma (CAPP) technology in the production of peptide-based materials has shown great potential in modern technology. Herein, two aggregation-prone oligopeptides, GNNQQNY and KLVFFA, were subjected to CAPP treatment to form supramolecular assemblies/aggregates. Through peptide engineering and biophysical techniques, the effect of CAPP-generated reactive oxygen and nitrogen species on the oligopeptides were investigated for different treatment times revealing that the formation of these aggregates were primarily driven by electrostatic interactions without any chemical modifications. Field emission-scanning electron microscopy and Thioflavin T (ThT) binding assay confirmed the presence of distinct β-strands, particularly in the aggregates of the KLVFFA peptide upon CAPP irradiation. The combination of CAPP technology with peptide self-assembly process and the characterization techniques employed in this study holds promise for the development of such peptide supramolecular structures based on the specific amino acid sequences.