bluuebunny/crossref_metadata_2025_split huggingface dataset:
PENGARUH MODEL PEMBELAJARAN STEAM (SCIENCE, TECHNOLOGY, ENGINEERING, ART, AND MATHEMATICS) TERHADAP PRESTASI BELAJAR SISWA PADA PEMBELAJARAN IPA KELAS V SEKOLAH DASAR
Authors: Rosiani Meilina 
Published: July 2023

Prestasi belajar merupakan tingkat keberhasilan siswa yang dicapai setelah melalui proses kegiatan belajar mengajar yang dinyatakan dalam bentuk skor dan diperoleh dari hasil tes. Sehingga penerapan model pembelajaran sangat berpengaruh terhadap pretasi belajar siswa. Penerapan model pembelajaran di Sekolah Dasar yang masih menggunakan model pembelajaran biasa, mengakibatkan prestasi belajar siswa menjadi belum meningkat, dalam hal ini diperluakn model pembelajaran yang mampu mempengaruhi peningkatan pretasi belajar siswa. Penelitian ini bertujuan untuk mengetahui pengaruh model pembelajaran STEAM (Science, Technology, Engineering, Art, and Mathematics) terhadap prestasi belajar siswa pada pembelajaran IPA siswa kelas V Sekolah Dasar. Jenis penelitian ini adalah bentuk desain experiment yang digunakan peneliti yaitu pre-experimental tipe one-group pretest-posttest design.Subjek penelitian ini adalah kelas VB yang berjumlah 25 siswa. Teknik pengambilan sampel dalam penelitian ini menggunakan simple random sampling. Teknik pengumpulan data prestasi belajar siswa menggunakan pretest dan posttest dengan bentuk soal essay. Analisis data menggunakan uji paired sample t-Test . Hasil menunjukan nilai rata-rata posttest lebih besar dari nilai rata-rata pretest, hal ini berarti ada peningkatan hasil belajar IPA sesudah diterapkan model pembelajaran STEAM. Hasil penelitian menunjukan bahwa nilai sig (2-tailed) sebesar 0,000 lebih kecil dari 0,05, dengan demikian Ho ditolak dan Ha diterima. Hal ini berarti ada perbedaan yang signifikan antara hasil belajar IPA sebelum dan sesudah diterapkan model pembelajaran STEAM (Science, Technology, Engineering, Art, and Mathematics).
Kata kunci: Model Pembelajaran STEAM, Prestasi Belajar
The Orbital Eccentricities of Directly Imaged Companions Using Observable-based Priors: Implications for Population-level Distributions
Authors: Do Ó Clarissa R. , O’Neil Kelly K. , Konopacky Quinn M. , Do Tuan , Martinez Gregory D. , Ruffio Jean-Baptiste , Ghez Andrea M. 
Published: July 2023

Abstract
The eccentricity of a substellar companion is an important tracer of its formation history. Directly imaged companions often present poorly constrained eccentricities. A recently developed prior framework for orbit fitting called “observable-based priors” has the advantage of improving biases in derived orbit parameters for objects with minimal phase coverage, which is the case for the majority of directly imaged companions. We use observable-based priors to fit the orbits of 21 exoplanets and brown dwarfs in an effort to obtain the eccentricity distributions with minimized biases. We present the objects’ individual posteriors compared to their previously derived distributions, showing in many cases a shift toward lower eccentricities. We analyze the companions’ eccentricity distribution at a population level, and compare this to the distributions obtained with the traditional uniform priors. We fit a Beta distribution to our posteriors using observable-based priors, obtaining shape parameters α =

1.09

−
0.22

+
0.30

and β =

1.42

−
0.25

+
0.33

. This represents an approximately flat distribution of eccentricities. The derived α and β parameters are consistent with the values obtained using uniform priors, though uniform priors lead to a tail at high eccentricities. We find that separating the population into high- and low-mass companions yields different distributions depending on the classification of intermediate-mass objects. We also determine via simulation that the minimal orbit coverage needed to give meaningful posteriors under the assumptions made for directly imaged planets is ≈15% of the inferred period of the orbit.
Splitting of Long-period Comet C/2018 F4 (PANSTARRS)
Authors: Hui 許 Man-To 文韜 , Kelley Michael S. P. , Hung Denise , Lister Tim , Chatelain Joseph , Gomez Edward , Greenstreet Sarah 
Published: July 2023

Abstract
Long-period comet C/2018 F4 (PANSTARRS) was observed to show duplicity of its inner region in 2020 September, suggestive of a splitting event. We here present analyses of our observations of the comet taken from the LCO Outbursting Objects Key project and the University of Hawaii 2.2 m telescope after the discovery of the splitting. The two fragments Components A and B, estimated to be ∼60 m to 4 km in radius, remained highly similar to each other in terms of brightness, color, and dust morphology throughout our observing campaign from 2020 September to 2021 December. Our fragmentation model yielded that the two components split at a relative speed of 3.00 ± 0.18 m s−1 in 2020 late April, implying a specific energy change of

5.3
±
2.8

×

10

3

J kg−1, and that Component B was subjected to a stronger nongravitational acceleration than Component A in both the radial and normal directions of the orbit. The obtained splitting time is broadly consistent with the result from the dust morphology analysis, which further suggested that the dominant dust grains were millimeter-sized and ejected at a speed of ∼2 m s−1. We postulate that the pre-split nucleus of the comet consisted of two lobes resembling that of 67P, or that the comet used to be a binary system like main-belt comet 288P. Regardless, we highlight the possibility of using observations of split comets as a feasible manner to study the bilobate shape or binarity fraction of cometary nuclei.
EXPRES. IV. Two Additional Planets Orbiting ρ Coronae Borealis Reveal Uncommon System Architecture
Authors: Brewer John M. , Zhao Lily L. , Fischer Debra A. , Roettenbacher Rachael M. , Henry Gregory W. , Llama Joe , Szymkowiak Andrew E. , Cabot Samuel H. C. , Weiss Sam A. , McCarthy Chris 
Published: July 2023

Abstract
Thousands of exoplanet detections have been made over the last 25 years using Doppler observations, transit photometry, direct imaging, and astrometry. Each of these methods is sensitive to different ranges of orbital separations and planetary radii (or masses). This makes it difficult to fully characterize exoplanet architectures and to place our solar system in context with the wealth of discoveries that have been made. Here, we use the EXtreme PREcision Spectrograph to reveal planets in previously undetectable regions of the mass–period parameter space for the star ρ Coronae Borealis. We add two new planets to the previously known system with one hot Jupiter in a 39 day orbit and a warm super-Neptune in a 102 day orbit. The new detections include a temperate Neptune planet (

M
sin
i
∼
20

M
⊕) in a 281.4 day orbit and a hot super-Earth (

M
sin
i
=
3.7

M
⊕) in a 12.95 day orbit. This result shows that details of planetary system architectures have been hiding just below our previous detection limits; this signals an exciting era for the next generation of extreme precision spectrographs.
Testing the Linear Relationship between Black Hole Mass and Variability Timescale in Low-luminosity AGNs at Submillimeter Wavelengths
Authors: Chen Bo-Yan , Bower Geoffrey C. , Dexter Jason , Markoff Sera , Ridenour Anthony , Gurwell Mark A. , Rao Ramprasad , Wallström Sofia H. J. 
Published: July 2023

Abstract
The variability of submillimeter emission provides a useful tool to probe the accretion physics in low-luminosity active galactic nuclei. We accumulate four years of observations using the Submillimeter Array for Centaurus A, NGC 4374, NGC 4278, and NGC 5077, and one year of observations for NGC 4552 and NGC 4579. All sources are variable. We measure the characteristic timescale at which the variability is saturated by modeling these sources’ light curves as a damped random walk. We detect a timescale for all the sources except NGC 4552. The detected timescales are comparable to the orbital timescale at the event horizon scale for most sources. Combined with previous studies, we show a correlation between the timescale and the black hole mass over 3 orders of magnitude. This discovery suggests the submillimeter emission is optically thin with the emission originating from the event horizon. The mass scaling relationship further suggests that a group of radio sources with a broadband spectrum that peaks at submillimeter wavelengths have similar inner accretion physics. Sources that follow this relationship may be good targets for high-resolution imaging with the Event Horizon Telescope.
High-energy Neutrino Production from AGN Disk Transients Impacted by the Circum-disk Medium
Authors: Zhou Zi-Hang , Zhu Jin-Ping , Wang Kai 
Published: July 2023

Abstract
Various supernovae, compact object coalescences, and tidal disruption events are widely believed to occur embedded in active galactic nucleus (AGN) accretion disks and generate detectable electromagnetic signals. We collectively refer to them as AGN disk transients. The inelastic hadronuclear (pp) interactions between shock-accelerated cosmic rays and AGN disk materials shortly after the ejecta shock breaks out of the disk can produce high-energy neutrinos. However, the expected efficiency of neutrino production would decay rapidly by adopting a pure Gaussian density atmosphere profile applicable for stable gas-dominated disks. On the other hand, AGN outflows and disk winds are commonly found around AGN accretion disks. In this paper, we show that the circum-disk medium would further consume the shock kinetic energy to more efficiently produce high-energy neutrinos, especially for ∼ TeV−PeV neutrinos that IceCube detects. Thanks to the existence of the circum-disk medium, we find that the neutrino production will be enhanced significantly and make a much higher contribution to the diffuse neutrino background. Optimistically, ∼20% of the diffuse neutrino background can be contributed by AGN disk transients.
Does Nature Allow the Formation of Ultra-compact Black Hole X-Ray Binaries via the Accretion-induced Collapse of Neutron Stars?
Authors: Chen Hai-Liang , Tauris Thomas M. , Chen Xuefei , Han Zhanwen 
Published: July 2023

Abstract
The formation path to ultracompact X-ray binaries (UCXBs) with black hole (BH) accretors is still unclear. In the classical formation scenario, it is difficult to eject the massive envelope of the progenitor star of the BH via the common envelope process. Given that some neutron stars (NSs) in binary systems evidently have birth masses close to ∼2.0 M
⊙, we explore here the possibility that BH-UCXBs may form via the accretion-induced collapse (AIC) of accreting NSs, assuming that these previously evolved in low-mass X-ray binaries to masses all the way up to the maximum limit of an NS. We demonstrate this formation path by modeling a few cases of NS-UCXBs with initial NS masses close to the maximum mass of an NS that evolve into BH-UCXBs after the NS accretes material from its He white dwarf (WD) companion. We follow the evolution of the post-AIC BH-UCXB and, based on simple arguments, we anticipate that there is about one BH-UCXB with an AIC origin and a He WD donor within the current sample of known UCXBs and that two to five such BH-UCXBs may be detected in gravitational waves by LISA. In addition, we find that the X-ray luminosity of NS-UCXBs near their orbital period minimum exceeds ∼1039 erg s−1, and thus, such systems may appear as ultraluminous X-ray sources.
Stellar Characterization and Radius Inflation of Hyades M-dwarf Stars from the APOGEE Survey
Authors: Wanderley Fábio , Cunha Katia , Souto Diogo , Smith Verne V. , Cao Lyra , Pinsonneault Marc , Allende Prieto C. , Covey Kevin , Masseron Thomas , Pascucci Ilaria , Stassun Keivan G. , Terrien Ryan , Bergsten Galen J. , Bizyaev Dmitry , Fernández-Trincado José G. , Jönsson Henrik , Hasselquist Sten , Holtzman Jon A. , Lane Richard R. , Mahadevan Suvrath , Majewski Steven R. , Minniti Dante , Pan Kaike , Serna Javier , Sobeck Jennifer , Stringfellow Guy S. 
Published: July 2023

Abstract
We present a spectroscopic analysis of a sample of 48 M-dwarf stars (0.2 M
⊙ < M < 0.6 M
⊙) from the Hyades open cluster using high-resolution H-band spectra from the Sloan Digital Sky Survey/Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey. Our methodology adopts spectrum synthesis with LTE MARCS model atmospheres, along with the APOGEE Data Release 17 line list, to determine effective temperatures, surface gravities, metallicities, and projected rotational velocities. The median metallicity obtained for the Hyades M dwarfs is [M/H] = 0.09 ± 0.03 dex, indicating a small internal uncertainty and good agreement with optical results for Hyades red giants. Overall, the median radii are larger than predicted by stellar models by 1.6% ± 2.3% and 2.4% ± 2.3%, relative to a MIST and DARTMOUTH isochrone, respectively. We emphasize, however, that these isochrones are different, and the fractional radius inflation for the fully and partially convective regimes have distinct behaviors depending on the isochrone. Using a MIST isochrone there is no evidence of radius inflation for the fully convective stars, while for the partially convective M dwarfs the radii are inflated by 2.7% ± 2.1%, which is in agreement with predictions from models that include magnetic fields. For the partially convective stars, rapid rotators present on average higher inflation levels than slow rotators. The comparison with SPOTS isochrone models indicates that the derived M-dwarf radii can be explained by accounting for stellar spots in the photosphere of the stars, with 76% of the studied M dwarfs having up to 20% spot coverage, and the most inflated stars with ∼20%–40% spot coverage.
From Dust to Nanodust: Resolving Circumstellar Dust from the Colliding-wind Binary Wolf-Rayet 140
Authors: Lau Ryan M. , Wang Jason , Hankins Matthew J. , Currie Thayne , Deo Vincent , Endo Izumi , Guyon Olivier , Han Yinuo , Jones Anthony P. , Jovanovic Nemanja , Lozi Julien , Moffat Anthony F. J. , Onaka Takashi , Ruane Garreth , Sander Andreas A. C. , Tinyanont Samaporn , Tuthill Peter G. , Weigelt Gerd , Williams Peredur M. , Vievard Sebastien 
Published: July 2023

Abstract
Wolf-Rayet (WR) 140 is the archetypal periodic dust-forming colliding-wind binary that hosts a carbon-rich WR (WC) star and an O-star companion with an orbital period of 7.93 yr and an orbital eccentricity of 0.9. Throughout the past few decades, multiple dust-formation episodes from WR 140 have been observed that are linked to the binary orbit and occur near the time of periastron passage. Given its predictable dust-formation episodes, WR 140 presents an ideal astrophysical laboratory to investigate the formation and evolution of dust in the hostile environment around a massive binary system. In this paper, we present near- and mid-infrared (IR) spectroscopic and imaging observations of WR 140 with Subaru/SCExAO+CHARIS, Keck/NIRC2+PyWFS, and Subaru/Cooled Mid-Infrared Camera and Spectrograph taken between 2020 June and September that resolve the circumstellar dust emission linked to its most recent dust-formation episode in 2016 December. Our spectral energy distribution analysis of WR 140's resolved circumstellar dust emission reveals the presence of a hot (T

d
∼ 1000 K) near-IR dust component that is co-spatial with the previously known and cooler (T

d
∼ 500 K) mid-IR dust component composed of 300–500 Å sized dust grains. We attribute the hot near-IR dust emission to the presence of nano-sized (nanodust) grains and suggest they were formed from grain–grain collisions or the rotational disruption of the larger grain size population by radiative torques in the strong radiation field from the central binary. Lastly, we speculate on the astrophysical implications of nanodust formation around colliding-wind WC binaries, which may present an early source of carbonaceous nanodust in the interstellar medium.
Critically Evaluated Atomic Data for the Au iv Spectrum
Authors: Zainab Aashna , Haris K. , Gamrath Sébastien , Quinet Pascal , Tauheed A. 
Published: July 2023

Abstract
A spectral investigation of triply ionized gold (Au iv) has been carried out in the wavelength region of 500–2106 Å. The gold spectra were photographed at the National Institute of Standards and Technology, USA, on a 10.7 m normal incidence vacuum spectrograph (NIVS) using a sliding spark source as well as on a 3 m NIVS at the Antigonish laboratory in Canada with a triggered spark source. Our analysis is theoretically supported by the pseudorelativistic Hartree–Fock (HFR) formalism with a superposition of configuration interactions implemented in Cowan's suite of codes. Radiative transition parameters are also calculated using the HFR+CPOL (core polarization effects) model and the multiconfiguration Dirac–Hartree–Fock approach, and their comparisons are used to evaluate the transition rate data. All the previously reported levels of the 5d
8, 5d
76s, and 5d
76p configurations are confirmed, except one, and three are newly established. The missing 1
S
0 level of 5d
8 is now established at 55,277.8 cm−1. A total of 981 observed lines (E1 type), classified to 1031 transitions, including 133 newly identified, enabled us to optimize 139 energy levels. Several astrophysically important transitions, forbidden (M1- and E2-type) lines of 5d
8 and 5d
76s, are provided with their Ritz wavelengths and radiative parameters. A critically evaluated set of energy levels, observed and Ritz wavelengths along with their uncertainties, transition rates, and uniformly scaled intensities of Au iv lines have been presented. Also, large-scale atomic data to compute the opacity of Au iv in the kilonova ejecta have been supplemented in this work.
Robust Data-driven Metallicities for 175 Million Stars from Gaia XP Spectra
Authors: Andrae René , Rix Hans-Walter , Chandra Vedant 
Published: July 2023

Abstract
We derive and publish data-driven estimates of stellar metallicity [M/H] for ∼175 million stars with low-resolution XP spectra published in Gaia DR3. The [M/H] values, along with T
eff and

log
g

, are derived using the XGBoost algorithm, trained on stellar parameters from APOGEE, augmented by a set of very-metal-poor stars. XGBoost draws on a number of data features: the full set of XP spectral coefficients, narrowband fluxes derived from XP spectra, and broadband magnitudes. In particular, we include CatWISE magnitudes, as they reduce the degeneracy of T
eff and dust reddening. We also include the parallax as a data feature, which helps constrain

log
g

and [M/H]. The resulting mean stellar parameter precision is 0.1 dex in [M/H], 50 K in T
eff, and 0.08 dex in

log
g

. This all-sky [M/H] sample is substantially larger than published samples of comparable fidelity across −3 ≲ [M/H] ≲ +0.5. Additionally, we provide a catalog of over 17 million bright (G < 16) red giants whose [M/H] values are vetted to be precise and pure. We present all-sky maps of the Milky Way in different [M/H] regimes that illustrate the purity of the data set, and demonstrate the power of this unprecedented sample to reveal the Milky Way’s structure from its heart to its disk.
Failures of Minimum Variance Analysis in Diagnosing Planar Structures in Space
Authors: Liu Y. Y. , Cao J. B. , Fu H. S. , Wang Z. , Guo Z. Z. , He R. J. 
Published: July 2023

Abstract
Minimum variance analysis of the magnetic field (MVAB), among various techniques of planar structure analysis, is most widely used for its numerical simplicity and loose requirements for data. Through a large number of studies based on MVAB, a global picture of the solar wind intermittency has been established. However, the huge discrepancy between the results from MVAB and other techniques like timing/triangulation implies that the uncertainty of MVAB is a crucial issue that is not fully understood. Utilizing Cluster data, we establish a data set comprised of 6752 discontinuities, whose orientations are precisely determined by timing, as a benchmark for testing MVAB. We find that the scatter of the MVAB normals around the timing normal can be reduced by elevating the threshold for the eigenvalue ratio λ
2/λ
3 and narrowing the data window to which MVAB is applied. The misidentification of discontinuities with

B

N

/

∣
B
∣

< 0.4, Δ∣
B
∣/∣
B
∣ < 0.2 as rotational discontinuities (RDs, identified by

B

N

/

∣
B
∣

> 0.4, Δ∣
B
∣/∣
B
∣ < 0.2) is proved to be a major and inherent defect of MVAB, which can occur even when λ
2/λ
3 is large. Such a misidentification process is revealed to be related to a special discontinuity geometry. It also explains the false RD predominance reported by previous studies based on MVAB. Finally, we provide advice for the application of MVAB and discuss the possibility of obtaining the real statistical properties of interplanetary discontinuities by using MVAB.
Investigación sobre el comportamiento meiótico en varias especies de Echinops L. (Asteraceae) de Irán
Authors: Alijanpoor Behnaz , Safaeishakib Masoumeh , Javadii Hamideh 
Published: July 2023

Echinops L., es un género de Asteraceae y contiene ca. 76 especies en Irán. La investigación actual se basa en seis especies y nueve poblaciones, incluidas E. cephalotus, E. chorassanicus, E. elebursessis, E. leiopolycerus, E. ritroides y E. robustus. La frecuencia y distribución de quiasmas, la asociación cromosómica y la segregación han sido analizadas para caracteres meióticos. En las especies estudiadas se han observado irregularidades meióticas, cromosomas no reducidos y otras anomalías relacionadas. Se observan también adherencia cromosómica, cromosomas rezagados, así como frecuentes formaciones de células tripolares y multipolares debido a fallos en la anafase I y II.
Distribución, hábitat potencial, población reproductora y estado de conservación del lagópodo alpino (Lagopus muta) en el Pirineo Central (Aragón-España)
Authors: Gil Juan A. , Pérez Carlos 
Published: July 2023

Se revisa, actualiza y obtiene información sobre el lagópodo alpino (Lagopus muta) en el Pirineo Central (Aragón-España). Se obtienen 303 observaciones (enero-diciembre 2000-2020), situándose la mayor parte de las observaciones entre 2.500 y 2.700 m.s.n.m. La especie está presente en 38 cuadrículas UTM de 10 x 10 km. Su hábitat potencial es de 832 km2 y su área de ocupación de 607,4 km2. El 82% del área de ocupación se localiza en Red Natura 2000. La superficie de ocupación en época reproductora (abril-octubre) es de 253,5 km2. Se estima una población de 1142 ±105 parejas. Especie catalogada como “Vulnerable” en Aragón, se desconoce su tendencia poblacional. Debido a los impactos causados por el cambio climático, los modelos predictivos establecen escenarios de contracciones en su distribución y disminución de sus efectivos poblacionales. Con la información obtenida se pueden establecer y mejorar las medidas de protección de la especie y su hábitat en los Planes de Conservación y Gestión de Aragón.
L’autre scène de Diderot
Authors: Armand Guilhem 
Published: July 2023

Trois œuvres mettent en scène Diderot ou un de ses doubles (en écho aux dialogues du philosophe) dans une perspective renouvelée, permise par le théâtre. Dans Mystification texte inachevé, à la frontière de la comédie et du dialogue, le personnage de Diderot met ironiquement en scène les limites de la philosophie pour en démontrer le pouvoir. Mais dans Est-il bon ? Est-il méchant ?, à travers Hardouin, qui n’est pas philosophe mais littérateur et bonhomme rendant service à tout le monde, il montre les limites de la philosophie morale affrontée au pragmatisme, en même temps qu’il représente tout ce qui empêche le vrai Diderot de mener à bien ses projets (littéraires et philosophiques). Enfin, dans Terentia (idée de Tronchin, développée par Diderot mais inachevée), il donne à voir Cicéron aux prises avec son impuissance à agir, conformément à l’idée que l’on en avait au xviiie siècle : le modèle du penseur grand rhétoricien, mais faible politique.