Miracle-dz/UniFAR-FTUs huggingface dataset:
Yet another family of diagonal metrics for de Sitter and anti–de Sitter spacetimes

In this work we present and analyze a new class of coordinate representations of de Sitter and anti-de Sitter spacetimes for which the metrics are diagonal and (typically) static and axially symmetric. Contrary to the well-known forms of these fundamental geometries, that usually correspond to a 1+3 foliation with the 3-space of a constant spatial curvature, the new metrics are adapted to a 2+2 foliation, and are warped products of two 2-spaces of constant curvature. This new class of (anti-)de Sitter metrics depends on the value of cosmological constant Lambda and two discrete parameters +1,0,-1 related to the curvature of the 2-spaces. The class admits 3 distinct subcases for Lambda>0 and 8 subcases for Lambda<0. We systematically study all these possibilities. In particular, we explicitly present the corresponding parametrizations of the (anti-)de Sitter hyperboloid, visualize the coordinate lines and surfaces within the global conformal cylinder, investigate their mutual relations, present some closely related forms of the metrics, and give transformations to standard de Sitter and anti-de Sitter metrics. Using these results, we also provide a physical interpretation of B-metrics as exact gravitational fields of a tachyon.
A Complete Sample of Soft X-Ray-selected AGNs. II. Statistical Analysis

Direct correlations and a principal component analysis (PCA) are presented for a complete sample of 110 soft X-ray–selected AGNs, of which about half are narrow-line Seyfert 1 galaxies (NLS1's). The direct correlation analyses show that narrower FWHM(Hβ) correlates with steeper X-ray spectrum, stronger optical Fe II emission, weaker [O III] emission and stronger short-term X-ray variability. This direct correlation analysis and the PCA confirm the Boroson & Green (1992) eigenvector 1 relationship for AGNs: Fe II strength anticorrelates with [O III] line strength. Eigenvector 1 is well correlated with the Eddington luminosity ratio L/LEdd, while eigenvector 2 shows a very good correlation with the mass of the central black hole MBH and the mass accretion rate . The Eddington ratio L/LEdd correlates with the X-ray spectral index αX and the black home mass MBH anticorrelates with the X-ray variability χ2/ν. The Eddington ratio L/LEdd may be interpreted as the age of an AGN: AGNs with steep X-ray spectra, strong Fe II, and weak [O III] are AGNs in an early phase of their evolution. In this hypothesis, NLS1's are young AGNs.
Osteology of Dashanpusaurus dongi (Sauropoda: Macronaria) and new evolutionary evidence from Middle Jurassic Chinese sauropods

The Middle Jurassic lower Shaximiao Formation in Sichuan Province of south-western China has yielded a diverse terrestrial vertebrate fauna dominated by sauropod dinosaurs. However, many of these sauropods lack detailed descriptions or explicit phylogenetic diagnoses. Here, we present a comprehensive redescription of Dashanpusaurus dongi, a species of sauropod found only in the lower Shaximiao Formation. We define the revised autapomorphies of the species as follows: neural canals are sub-square in anterior dorsal vertebrae; the presence of a thin accessory lamina that contacts the prezygodiapophyseal and paradiapophyseal laminae of the middle dorsals, forming an angle of 75° to the horizontal; and four ridges on the anterodistal edge of the humerus. Often considered part of the epipophyseal-prezygapophyseal lamina, a strut invades the spinodiapophyseal fossa in the cervical and anterior dorsal vertebrae. Anatomical comparisons indicate that this feature was widespread among early-diverging Middle Jurassic eusauropod lineages. This comparative anatomical data provides an opportunity to revisit the phylogenetic position of Dashanpusaurus and the relationships of the neosauropod clade. Recovered as a macronarian, a better understanding of Dashanpusaurus dongi will allow for clarification of the origin, early evolution, and palaeogeographical distribution of neosauropods. This study also suggests that the diversity and dispersity of the neosauropod clade occurred much earlier than previously realized.
Competition of Dimerization and Charge Ordering in the Spin-Peierls State of Organic Conductors

The effect of the charge ordering on the spin–Peierls (SP) state has been examined by using a Peierls–Hubbard model at quarter-filling with dimerization, on-site and nearest-neighbor repulsive interactions. By taking account of the presence of dimerization, a bond distortion is calculated variationally with the renormalization group method based on bosonization. When the charge ordering appears at V = V c with increasing the nearest-neighbor interaction ( V ), the distortion exhibits a maximum due to competition between the dimerization and the charge ordering. It is shown that the second-order phase transition occurs from the SP state with the bond alternation to a mixed state with an additional component of the site alternation at V = V c .
Growing Through the Cracks: Community-Engaged Education and Countering School Disengagement

In this paper, I lay out the possibilities for community-engaged education as a tool for countering school disengagement with marginalized youth in Toronto. Using interviews and observations with staff, youth, and parents who participate in a community-based tutoring and mentoring program, I explore how the program’s grassroots commitments work to minimize marginalization and the pushout of students within the Latinx and Portuguese communities in Toronto. By building relationships based on trust and responding to the community’s needs, parental engagement, and academic-community partnerships, the program creates a space of community engagement that involves the whole family in changing narratives about both communities and their place within the public education system. I posit that this type of community-engaged education is effective in increasing access to postsecondary education for traditionally marginalized students.
Mangrove zonation, community structure and healthiness in Kei Islands, Maluku, Indonesia

Abstract. Dharmawan IWE, Renyaan J, Nurdiansah D. 2022. Mangrove zonation, community structure and healthiness in Kei Islands, Maluku, Indonesia. Biodiversitas 23: 4918-4927. Forest structure and quality were studied in an archipelagic site in Indonesia which consists of estuarine and oceanic mangrove habitats. This study aimed to determine mangrove structure and estimate the spatial distribution of forest healthiness along the zones dominated by different genera. Forest zones were investigated using the Random Forest method utilizing a cloud-free Harmonized Sentinel-2A-Surface Reflectance image. Community structure measurement followed a stratified purposive sampling design along forest zonation. A spatial-based mangrove health index (MHI) model was applied to analyze forest healthiness distribution in each zone. Mangrove area was clearly classified into six genera-dominated zones such as Sonneratia, Rhizophora, Bruguiera, Ceriops, Xylocarpus and Lumnitzera from seaward to landward. The Rhizophora zone had the most extensive area proportion at approximately 68% of the total mangrove area. This study revealed that S. alba species dominated in the outmost zone at about 200% of IVI, while X. granatum and C. tagal were calculated in a larger IVI value in the more landward area. On the other hand, R. stylosa had a majority species composition in Rhizophora forest. According to spatial analysis of MHI, most zones had a majority area of excellent condition, emphasizing that the entire mangrove forest was pristine.
Near-Infrared Bright Galaxies at z ≃ 2. Entering the Spheroid Formation Epoch?

Spectroscopic redshifts have been measured for nine K-band luminous galaxies at 1.7 < z < 2.3, selected with Ks < 20 in the K20 survey region of the Great Observatories Origins Deep Survey (GOODS) area. Star formation rates (SFRs) of ~100-500 M☉ yr-1 are derived when dust extinction is taken into account. The fitting of their multicolor spectral energy distributions indicates stellar masses of M ≳ 1011 M☉ for most of the galaxies. Their rest-frame UV morphology is highly irregular, suggesting that merging-driven starbursts are going on in these galaxies. Morphologies tend to be more compact in the near-IR, a hint for the possible presence of older stellar populations. Such galaxies are strongly clustered, with seven out of nine belonging to redshift spikes, which indicates a correlation length of r0 ~ 9-17 h-1 Mpc (1 σ range). Current semianalytical models of galaxy formation appear to underpredict by a large factor (≳30) the number density of such a population of massive and powerful starburst galaxies at z ~ 2. The high masses and SFRs, together with the strong clustering, suggest that at z ~ 2 we may have started to explore the major formation epoch of massive early-type galaxies.
GRB010222: afterglow emission from a rapidly decelerating shock ⋆

The GRB010222 optical and near-infrared (NIR) afterglow was monitored at the TNG and other Italian telescopes starting1 day after the high-energy prompt event. TheBVR light curves, which are the best sampled, are continuously steepening and can be described by two power laws, f(t)/ t , of indices 1 0.7 and 2 1.3 before and after a break occurring at about 0.5 days after the GRB start time, respectively. This model accounts well also for the flux in the U, I and J bands, which are less well monitored. The temporal break appears to be achromatic. The two K-band points are not consistent with the above behaviour, and rather suggest a constant trend. A low-resolution optical spectrum has also been taken with TNG. In the optical spectrum we found three absorption systems at dierent redshifts (0.927, 1.155 and 1.475), the highest of which represents a lower limit to, and probably coincides with, the redshift of the GRB. The broad-band optical spectral energy distributions do not appear to vary with time, consistently with the achromatic behaviour of the light curves. We compare our measurements with dierent afterglow evolution scenarios and we nd that they favor a transition from relativistic to non-relativistic conditions in the shock propagation.
Ichthyofauna diversity in Pematang Matik Coastal Waters, Serdang Bedagai District, North Sumatra, Indonesia

Abstract. Wahyuningsih H, Sinaga SMS, Hartanto A. 2022. Ichthyofauna diversity in Pematang Matik Coastal Waters, Serdang Bedagai District, North Sumatra. Biodiversitas 23: 4992-5000. Pematang Matik Coastal waters are coastal areas that have a major role in the life of various fish species. Research on fish diversity in coastal waters is very important in order to gain a better understanding on the fish diversity in coastal areas such as North Sumatra, including Indonesia. The objective of this study was to initiate an inventory of fish species, their abundance and assessment of its biodiversity based on Shannon's diversity index (H'), and evenness index (E) in Pematang Matik coastal waters. The research was conducted from September to October 2021 at four stations with different human activities by the coastal community. Fish samples were taken using fishing nets that were installed for 12 hr with two replications. In this study, 21 species of fish from 19 families were identified. The highest abundance of fish was obtained from the Mugilidae family, namely Crenimugil crenilabis and Liza macrolepis. The fish diversity index obtained was 2.19-2.95, while the uniformity index obtained was 0.719-0.968. The values ? of H' and E at Station 4 (absent from any human interferences) have higher values ? than the other three stations. The diversity, as expressed in H' value in four research stations, indicates that the coastline has a high diversity of fish species.
THE INTERPRETATION OF THE MULTI-WAVELENGTH AFTERGLOW EMISSION OF SHORT GRB 140903A

GRB 140903A, a short duration γ-ray burst (SGRB) detected by Swift, is characterized by its long-lasting radio emission among SGRBs. In addition to the ∼ 10 6 s radio afterglow emission, the afterglow of GRB 140903A displays a plateau from 103 s to 7 × 10 3 s in the X-rays. In this work, we attribute the X-ray plateau to the energy injection into the decelerating blast wave and then model the later radio/optical/X-ray afterglow emission within the standard fireball afterglow model. The afterglow emission has been well reproduced with reasonable physical parameters, including a jet half-opening angle of ∼0.05.
Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios: associations with mortality in a haemodialysis cohort

ABSTRACT Background Lymphocyte ratios reflect inflammation and have been associated with adverse outcomes in a range of diseases. We sought to determine any association between neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) and mortality in a haemodialysis cohort, including a coronavirus disease 2019 (COVID-19) infection subpopulation. Methods A retrospective analysis was performed of adults commencing hospital haemodialysis in the West of Scotland during 2010–21. NLR and PLR were calculated from routine samples around haemodialysis initiation. Kaplan–Meier and Cox proportional hazards analyses were used to assess mortality associations. Results In 1720 haemodialysis patients over a median of 21.9 (interquartile range 9.1–42.9) months, there were 840 all-cause deaths. NLR but not PLR was associated with all-cause mortality after multivariable adjustment [adjusted hazard ratio (aHR) for in participants with baseline NLR in quartile 4 (NLR ≥8.23) versus quartile 1 (NLR <3.12) 1.63, 95% confidence interval (CI) 1.32–2.00]. The association was stronger for cardiovascular death (NLR quartile 4 versus 1 aHR 3.06, 95% CI 1.53–6.09) than for non-cardiovascular death (NLR quartile 4 versus 1 aHR 1.85, 95% CI 1.34–2.56). In the COVID-19 subpopulation, both NLR and PLR at haemodialysis initiation were associated with risk of COVID-19-related death after adjustment for age and sex (NLR: aHR 4.69, 95% CI 1.48–14.92 and PLR: aHR 3.40, 95% CI 1.02–11.36; for highest vs lowest quartiles). Conclusions NLR is strongly associated with mortality in haemodialysis patients while the association between PLR and adverse outcomes is weaker. NLR is an inexpensive, readily available biomarker with potential utility in risk stratification of haemodialysis patients.
A Dual-Process Account of Major Social Constructs of Motivation: Implications for Leadership Scholarship

There is inconsistency in positioning general motivation constructs within the broader leadership research. The main purpose of the current study was to review major social constructs of motivation applied in leadership studies and then empirically investigate their associations. Data was collected using self-reported measures from 316 business students to test our theoretical models. Properties of the models, including validity and common method bias, were assessed and controlled before hypothesis testing using variance-based structural equation modeling. This study offers several original contributions. First, reviewing the literature, we identify major social constructs of motivation central to leadership studies including self-efficacy, self-regulation, causal attributions, goal orientation, intrinsic and extrinsic motivation. Second, applying the regulatory focus perspective, we offer a new taxonomy of the constructs (promotional vs. preventive). Third, using empirical data, we establish a nomological network amongst the six social constructs of motivation. The study yielded an integrative theory of motivation by establishing a network of cause-and-effect amongst six popular social constructs of motivation in leadership research. Two complementary (promotional vs. preventive) models of motivation were developed to predict dimensions of creative outcome (idea generation and exploration). Forth, building on the findings, we provide early evidence for further decomposition of general self-efficacy constructs into “promotional self - efficacy” vs. “preventive self - efficacy”. Implications of the findings for leadership research were also discussed.
A Multi-Stage Deep-Learning-Based Vehicle and License Plate Recognition System with Real-Time Edge Inference

Video streaming-based real-time vehicle identification and license plate recognition systems are challenging to design and deploy in terms of real-time processing on edge, dealing with low image resolution, high noise, and identification. This paper addresses these issues by introducing a novel multi-stage, real-time, deep learning-based vehicle identification and license plate recognition system. The system is based on a set of algorithms that efficiently integrate two object detectors, an image classifier, and a multi-object tracker to recognize car models and license plates. The information redundancy of Saudi license plates’ Arabic and English characters is leveraged to boost the license plate recognition accuracy while satisfying real-time inference performance. The system optimally achieves real-time performance on edge GPU devices and maximizes models’ accuracy by taking advantage of the temporally redundant information of the video stream’s frames. The edge device sends a notification of the detected vehicle and its license plate only once to the cloud after completing the processing. The system was experimentally evaluated on vehicles and license plates in real-world unconstrained environments at several parking entrance gates. It achieves 17.1 FPS on a Jetson Xavier AGX edge device with no delay. The comparison between the accuracy on the videos and on static images extracted from them shows that the processing of video streams using this proposed system enhances the relative accuracy of the car model and license plate recognition by 13% and 40%, respectively. This research work has won two awards in 2021 and 2022.
The Far-infrared Emission of the First Massive Galaxies

Massive Population II galaxies undergoing the first phase of vigorous star formation after the initial Population III stage should have high energy densities and silicate-rich interstellar dust. We have modeled the resulting far-infrared spectral energy distributions (SEDs), demonstrating that they are shifted substantially to bluer (“warmer”) wavelengths relative to the best fitting ones at z ≈ 3, and with strong outputs in the 10–40 μm range. When combined with a low level of emission by carbon dust, their SEDs match that of Haro 11, a local moderately low-metallicity galaxy undergoing a very young and vigorous starburst that is likely to approximate the relevant conditions in young Population II galaxies. We expect to see similar SEDs at high redshifts (z ≳ 5) given the youth of galaxies at this epoch. In fact, we find a progression with redshift in observed galaxy SEDs, from those resembling local ones at 2 ≲ z < 4 to a closer resemblance with Haro 11 at 5 ≲ z < 7. In addition to the insight on conditions in high-redshift galaxies, this result implies that estimates of the total infrared luminosities at z ∼ 6 based on measurements near λ ∼ 1 mm can vary by factors of 2–4, depending on the SED template used. Currently popular modified blackbodies or local templates can result in significant underestimates compared with the preferred template based on the SED of Haro 11.
Analytic treatment of black-hole gravitational waves at the algebraically special frequency

We study the Regge-Wheeler (RWE) and Zerilli equations (ZE) at the "algebraically special frequency" Omega, where these equations admit an exact solution (elaborated here), generating the supersymmetry (SUSY) relationship between them. The physical significance of the SUSY generator and of the solutions at Omega in general is elucidated as follows. The RWE has no (quasinormal or total-transmission) modes at all; however, Omega is nonetheless "special" in that (a) for the outgoing wave into the horizon one has a "miraculous" cancellation of a divergence expected due to the exponential potential tail, and (b) the branch-cut discontinuity at omega = Omega vanishes in the outgoing wave to infinity. Moreover, (a) and (b) are related. For the ZE, its only mode is the-inverse-SUSY generator, which is at the same time a quasinormal mode and a total-transmission mode propagating to infinity. The subtlety of these findings (of general relevance for future study of the equations on or near the negative imaginary omega-axis) may help explain why the situation has sometimes been controversial. For finite black-hole rotation, the algebraically special modes are shown to be totally transmitting, and the implied singular nature of the Schwarzschild limit is clarified. The analysis draws on a recent detailed investigation of SUSY in open systems [math-ph/9909030].
Detection of helicoidal motion in the optical jet of PKS 0521−365

The jet activity of Active Galactic Nuclei (AGN), and its interaction with the interstellar medium (ISM), may play a pivotal role in the processes which regulate the growth and star formation of its host galaxy. Observational evidence which pinpoints the conditions of such interaction is paramount to unveil the physical processes involved. We report on the discovery of extended emission line regions exhibiting an S-shaped morphology along the optical jet of the radio-loud AGN $\text{PKS}\,0521-365$ ($z=0.055$), by using long-slit spectroscopic observations obtained with FORS2 on VLT. The velocity pattern derived from the $\text{[O II]}\,\lambda 3727\,\AA,\, \text{H}\beta\, \lambda 4861\,\AA\,$ and [O III] $\lambda\lambda4959,5007\,\AA\,$ emission lines is well-fitted by a sinusoidal function of the form: $v(r)=\alpha r^{1/2}sin(\beta r^{1/2}+\gamma)$, suggesting helicoidal motions along the jet up to distances of $20\,\text{kpc}$. We estimate a lower limit for the mass of the outflowing ionized gas along the jet of $\sim$10$^4\,M_\odot$. Helical magnetic fields and jet precession have been proposed to explain helicoidal paths along the jet at pc scales; nevertheless, it is not clear yet whether these hypotheses may hold at kpc scales.
Two-to-three dimensional transition in neutral gold clusters: The crucial role of van der Waals interactions and temperature

We predict the structures of neutral gas-phase gold clusters ($Au_n$, $n$ = 5$-$13) at finite temperatures based on free-energy calculations obtained by replica-exchange ab initio molecular dynamics. The structures of neutral $Au_5$$-$$Au_{13}$ clusters are assigned at 100 K based on a comparison of experimental far-infrared multiple photon dissociation spectra performed on Kr-tagged gold clusters with theoretical anharmonic IR spectra and free-energy calculations. The critical gold cluster size where the most stable isomer changes from planar to nonplanar is $Au_{11}$ (capped-trigonal prism, $D_{3h}$) at 100 K. However, at 300 K (i.e., room temperature), planar and nonplanar isomers may coexist even for $Au_8$, $Au_9$, and $Au_{10}$ clusters. Density-functional theory exchange-correlation functionals within the generalized gradient or hybrid approximation must be corrected for long-range van der Waals interactions to accurately predict relative gold cluster isomer stabilities. Our work gives insight into the stable structures of gas-phase gold clusters by highlighting the impact of temperature, and therefore the importance of free-energy over total energy studies, and long-range van der Waals interactions on gold cluster stability.