bluuebunny/crossref_metadata_2025 huggingface dataset:
Discovery of a new blue large-amplitude pulsator in the SkyMapper DR2: SMSS J184506.82−300804.7
Authors: Chang Seo-Won , Wolf Christian , Onken Christopher A , Bessell Michael S
Published: March 2024

We report the discovery of a new Blue Large-Amplitude Pulsator (BLAP), SMSS J184506−300804 (SMSS-BLAP-1) in Data Release 2 of the SkyMapper Southern Sky Survey. We conduct high-cadence photometric observations in the u band to confirm a periodic modulation of the light curve. SMSS-BLAP-1 has a ∼19-min pulsation period with an amplitude of 0.2 mag in u band, and is similar to the classical BLAPs found by OGLE. From spectroscopic observations with the Wide-Field Spectrograph on the Australian National University 2.3m telescope, we confirm it as a low-gravity BLAP: best-fitting parameters from the non-LTE tlusty model are estimated as Teff = 29 020$^{+193}_{-34}$ K, logg = 4.661$^{+0.008}_{-0.143}$ (cm s−2), and logn(He)/n(H) = −2.722$^{+0.057}_{-0.074}$ dex. However, our BLAP exhibits a very He-deficient atmosphere compared to both low- and high-gravity BLAPs, which have logn(He)/n(H) in the range −0.41∼−2.4.
Searching for globular clusters in the inner halo of the Circinus galaxy
Authors: Obasi C , Gómez M , Minniti D , Baravalle L D , Alonso M V , Okere B I
Published: March 2024

In this study, we search for globular clusters (GCs) in the inner halo of the Circinus galaxy using a combination of observational data. Our data set includes observations from the VISTA Variables in the Vía Láctea Extended Survey (VVVX), optical data from Gaia Release 3 (DR3), and observations from the Dark Energy Camera (DECam). These multiple data sources provide a comprehensive basis for our analysis. Our search was concentrated within a 50 kpc radius from the centre, leading to the identification of 93 sources that met our established criteria. To ensure the reliability of our findings, we conducted multiple examinations for sample contamination. These examinations incorporated tests based on Gaia Astrometric Excess Noise (AEN), the blue photometer/red photometer (BRexcess) excess factor, as well as comparisons with stellar population models. This analysis confidently classified 41 sources as genuine GCs, as they successfully passed both the 3σ Gaia AEN and BRexcess tests. We used the ISHAPE program to determine the structural parameters (half-light radii) of the GC candidates, with a peak effective radius of 4 ± 0.5 pc. The catalogue mainly consists of bright GCs. Relationships between colour, size, and distance were found in the GC candidates, alongside confirmation of bi-modality in colour distributions.
Short and long time-scales variability of the H α double-peaked profile of Pictor A
Authors: Marsango Daniel , Schimoia Jáderson S , Rembold Sandro B , Storchi-Bergmann Thaisa , Nemmen Rodrigo S , Couto Guilherme S , Souza-Oliveira Gabriel Luan , Costa-Souza José Henrique
Published: March 2024

We present the results of the analysis of 18 optical spectra covering the H α profile region of the active nucleus of the galaxy Pictor A obtained in different epochs along 12 yr. With these data, we model the variability of the double-peaked H α emission of the nucleus of this galaxy. We find small variations in the integrated flux of the broad component of H α, occurring on short time-scales, of the order of 40 d. In addition, significant variations in the relative intensities of the red and blue sides of the broad profile occur on time-scales of years. In order to explain the observations, we propose a scenario in which the double-peak profile is produced by a flattened distribution of clouds surrounding the accretion disc with Keplerian and relativistic orbits, inclined in relation to the sky plane, and with axially asymmetric surface emissivity with the radius of maximum emissivity. We find that, for the theoretical time-scales of the disc-like BLR to conform the time-scales of variation observed for the double-peak profile, it is necessary for the gas in the disc to orbit a SMBH with a mass of M• $\approx \, 2\times$ $10^{8}\, \mbox{M}_\odot$. In this scenario, the physical extension of the line-emitting region extends by 6–48 light-days from the SMBH.
The effects of non-linearity on the growth rate constraint from velocity correlation functions
Authors: Tonegawa Motonari , Appleby Stephen , Park Changbom , Hong Sungwook E , Kim Juhan
Published: March 2024

The two-point statistics of the cosmic velocity field, measured from galaxy peculiar velocity (PV) surveys, can be used as a dynamical probe to constrain the growth rate of large-scale structures in the Universe. Most works use the statistics on scales down to a few tens of Megaparsecs, while using a theoretical template based on the linear theory. In addition, while the cosmic velocity is volume-weighted, the observable line-of-sight velocity two-point correlation is density-weighted, as sampled by galaxies, and therefore the density–velocity correlation term also contributes, which has often been neglected. These effects are fourth order in powers of the linear density fluctuation $\delta _{\rm L}^4$, compared to $\delta _{\rm L}^2$ of the linear velocity correlation function, and have the opposite sign. We present these terms up to $\delta _{\rm L}^4$ in real space based on the standard perturbation theory, and investigate the effect of non-linearity and the density–velocity contribution on the inferred growth rate fσ8, using N-body simulations. We find that for a next-generation PV survey of volume $\sim {\cal O}(500 \, h^{-1} \, {\rm Mpc})^3$, these effects amount to a shift of fσ8 by ∼10 per cent and is comparable to the forecasted statistical error when the minimum scale used for parameter estimation is $r_{\rm min} = 20 \, h^{-1} \, {\rm Mpc}$.
The dynamics of accretion flows near to the innermost stable circular orbit
Authors: Mummery Andrew , Mori Francesco , Balbus Steven
Published: March 2024

Accretion flows are fundamentally turbulent systems, yet are classically modelled with viscous theories only valid on length scales significantly greater than the typical size of turbulent eddies in the flow. We demonstrate that, while this will be a reasonable bulk description of the flow at large radii, this must break down as the flow approaches absorbing boundaries, such as the innermost stable circular orbit (ISCO) of a black hole disc. This is because in a turbulent flow large velocity fluctuations can carry a fluid element over the ISCO from a finite distance away, from which it will not return, a process without analogy in conventional models. This introduces a non-zero directional bias into the velocity fluctuations in the near-ISCO disc. By studying reduced random walk problems, we derive a number of implications of the presence of an absorbing boundary in an accretion context. In particular, we show that the average velocity with which a typical fluid element crosses the ISCO is much larger than is assumed in traditional theories. This enhanced velocity modifies the thermodynamic properties of black hole accretion flows on both sides of the ISCO. In particular, thermodynamic quantities for larger ISCO stresses no longer display pronounced cusps at the ISCO in this new formalism, a result with relevance for a number of observational probes of the intra-ISCO region. Finally, we demonstrate that these extended models reproduce the trans-ISCO behaviour observed in GRMHD simulations of thin discs.
The double-peaked type I X-ray bursts with different mass accretion rate and fuel composition
Authors: Song Liyu , Liu Helei , Zhu Chunhua , Zhen Guoqing , Lü Guoliang , Xu Renxin
Published: March 2024

Using the mesa (Modules for Experiments in Stellar Astrophysics) code, we have carried out a detailed survey of the available parameter space for the double-peaked type I X-ray bursts. We find that the double-peaked structure appears at mass accretion rate $\dot{M}$ in the range of $\sim (4-8)\times 10^{-10}\, {\rm M}_{\odot }\,{\rm yr}^{-1}$ when metallicity Z = 0.01, while in the range of $\sim (4-8)\times 10^{-9}\, {\rm M}_{\odot }\,\rm {yr}^{-1}$ when Z = 0.05. Calculations of the metallicity impact suggest that the double peaks will disappear when Z ≲ 0.005 for $\dot{M}=5\times 10^{-10}\, {\rm M}_{\odot }\,\rm {yr}^{-1}$ and Z ≲ 0.04 for $\dot{M}=5\times 10^{-9}\, {\rm M}_{\odot }\,\rm {yr}^{-1}$. Besides, the impacts of base heating Qb, as well as nuclear reaction waiting points: $^{22}\rm {Mg}$, $^{26}\rm {Si}$, $^{30}\rm {S}$, $^{34}\rm {Ar}$, 56Ni, $^{60}\rm Zn$, $^{64}\rm {Ge}$, $^{68}\rm {Se}$, and $^{72}\rm {Kr}$ have been explored. The luminosity of the two peaks decreases as Qb increases. 68Se(p, γ)69Br is the most sensitive reaction, the double peaks disappear assuming that 56Ni(p, γ)57Cu, and 64Ge(p, γ)65As reaction rates have been underestimated by a factor of 100 and the 22Mg(α, p)25Al reaction rate has been overestimated by a factor of 100, which indicates that 22Mg, 56Ni, 64Ge, and 68Se are possibly the most important nuclear waiting points impedance in the thermonuclear reaction flow to explain the double-peaked bursts. Comparisons to the double-peaked bursts from 4U 1636−53 and 4U 1730−22 suggest that the nuclear origins of double-peaked type I X-ray bursts are difficult to explain the observed larger peak times ($t_{\rm p,1}\gtrsim 4\, {\rm s}$, $t_{\rm p,2}\gtrsim 8\, {\rm s}$) and smaller peak ratio (r1, 2 ≲ 0.5). The composition of ashes from double-peaked bursts is very different from the single-peaked bursts especially for the heavier p-nuclei.
A.C.I.D – an improved LSD technique for accurate line profile retrieval
Authors: Dolan Lucy S , de Mooij Ernst J W , Watson Christopher A , Jackson David G
Published: March 2024

Stellar activity and planetary effects induce radial velocity (RV) offsets and cause temporal distortions in the shape of the stellar line profile. Hence, accurately probing the stellar line profile offers a wealth of information on both the star itself and any orbiting planets. Typically, cross-correlation functions (CCFs) are used as a proxy for the stellar line profile. The shape of CCFs, however, can be distorted by line blending and aliasing limiting the stellar and planetary physics that can be probed from them. Least-squares deconvolution (LSD) offers an alternative that directly fits the mean line profile of the spectrum to produce a high-precision profile. In this paper, we introduce our novel method ACID (Accurate Continuum fItting and Deconvolution) that builds on LSD techniques by simultaneously fitting the spectral continuum and line profile as well as performing LSD in effective optical depth. Tests on model data revealed ACID can accurately identify and correct the spectral continuum to retrieve an injected line profile. ACID was also applied to archival High Accuracy Radial-velocity Planet Searcher (HARPS) data obtained during the transit of HD189733b. The application of the Reloaded Rossiter–McLaughlin technique to both ACID profiles and HARPS CCFs shows ACID residual profiles improved the out-of-line root mean square (RMS) by over 5 per cent compared to CCFs. Furthermore, ACID profiles are shown to exhibit a Voigt profile shape that better describes the expected profile shape of the stellar line profile. This improved representation shows that ACID better preserves the stellar and planetary physics encoded in the stellar line profile shape for slow rotating stars.
The epoch of the Milky Way’s bar formation: dynamical modelling of Mira variables in the nuclear stellar disc
Authors: Sanders Jason L , Kawata Daisuke , Matsunaga Noriyuki , Sormani Mattia C , Smith Leigh C , Minniti Dante , Gerhard Ortwin
Published: March 2024

A key event in the history of the Milky Way is the formation of the bar. This event affects the subsequent structural and dynamical evolution of the entire Galaxy. When the bar formed, gas was likely rapidly funnelled to the centre of the Galaxy settling in a star-forming nuclear disc. The Milky Way bar formation can then be dated by considering the age distribution of the oldest stars in the formed nuclear stellar disc. In this highly obscured and crowded region, reliable age tracers are limited, but bright, high-amplitude Mira variables make useful age indicators as they follow a period–age relation. We fit dynamical models to the proper motions of a sample of Mira variables in the Milky Way’s nuclear stellar disc region. Weak evidence for inside-out growth and both radial and vertical dynamical heating with time of the nuclear stellar disc is presented, suggesting that the nuclear stellar disc is dynamically well-mixed. Furthermore, for Mira variables around a ∼350-d period, there is a clear transition from nuclear stellar disc-dominated kinematics to background bar-bulge-dominated kinematics. Using a Mira variable period–age relation calibrated in the solar neighbourhood, this suggests the nuclear stellar disc formed in a significant burst in star formation $(8\pm 1)\, \mathrm{Gyr}$ ago, although the data are also weakly consistent with a more gradual formation of the nuclear stellar disc at even earlier epochs. This implies a relatively early formation time for the Milky Way bar ($\gtrsim 8\, \mathrm{Gyr}$), which has implications for the growth and state of the young Milky Way and its subsequent history.
MIGHTEE-H i: H i galaxy properties in the large-scale structure environment at z ∼ 0.37 from a stacking experiment
Authors: Sinigaglia Francesco , Rodighiero Giulia , Elson Ed , Bianchetti Alessandro , Vaccari Mattia , Maddox Natasha , Ponomareva Anastasia A , Frank Bradley S , Jarvis Matt J , Catinella Barbara , Cortese Luca , Roychowdhury Sambit , Baes Maarten , Collier Jordan D , Ilbert Olivier , Khostovan Ali A , Kurapati Sushma , Pan Hengxing , Prandoni Isabella , Rajohnson Sambatriniaina H A , Salvato Mara , Sekhar Srikrishna , Sharma Gauri
Published: March 2024

We present the first measurement of H i mass of star-forming galaxies in different large scale structure environments from a blind survey at z ∼ 0.37. In particular, we carry out a spectral line stacking analysis considering 2875 spectra of colour-selected star-forming galaxies undetected in H i at 0.23 < z < 0.49 in the COSMOS field, extracted from the MIGHTEE-H i Early Science data cubes, acquired with the MeerKAT radio telescope. We stack galaxies belonging to different subsamples depending on three different definitions of large-scale structure environment: local galaxy overdensity, position inside the host dark matter halo (central, satellite, or isolated), and cosmic web type (field, filament, or knot). We first stack the full star-forming galaxy sample and find a robust H i detection yielding an average galaxy H i mass of $M_{\rm H \, {\small I}}=(8.12\pm 0.75)\times 10^9\, {\rm M}_\odot$ at ∼11.8σ. Next, we investigate the different subsamples finding a negligible difference in MH i as a function of the galaxy overdensity. We report an H i excess compared to the full sample in satellite galaxies (MH i = (11.31 ± 1.22) × 109, at ∼10.2σ) and in filaments (MH i = (11.62 ± 0.90) × 109. Conversely, we report non-detections for the central and knot galaxies subsamples, which appear to be H i-deficient. We find the same qualitative results also when stacking in units of H i fraction (fH i). We conclude that the H i amount in star-forming galaxies at the studied redshifts correlates with the large-scale structure environment.
An analytical description of substructure-induced gravitational perturbations in stellar systems
Authors: Delos M Sten
Published: March 2024

Perturbations to stellar systems can reflect the gravitational influence of dark matter substructures. On scales much smaller than the size of a stellar system, we point out analytical connections between the stellar and dark matter distributions. In particular, the density and velocity power spectra of the stars are proportional to the density power spectrum of the perturbing dark matter, scaled by k−4. This relationship allows easy evaluation of the suitability of a stellar system for detecting dark substructure. As examples, we show that the Galactic stellar halo is expected to be sensitive to cold dark matter substructure at wavenumbers k ≲ 0.3 kpc−1, and the Galactic disc might be sensitive to substructure at wavenumbers k ∼ 4 kpc−1. The perturbations considered in this work are short-lived, being rapidly erased by the stellar velocity dispersion, so it may be possible to attribute a detection to dark matter substructure without ambiguity.
Tolerability, safety and efficacy of a novel phosphate binder VS-505 (AP301): a Phase 2 dose-escalation and dose-ranging study in patients undergoing maintenance hemodialysis
Authors: Zhuang Bing , Gan Liangying , Liu Bin , Yuan Weijie , Shi Ming , Peng Ai , Wang Lihua , Chen Xiaolan , Liu Tongqiang , Zhang Shiying , Wang Song , Gao Qing , Wang Baoxing , Zheng Huixiao , Liu Changhua , Luo Yuan , Ye Hong , Lin Hongli , Li Yiwen , He Qiang , Zheng Feng , Luo Ping , Long Gang , Lu Wei , Li Kanghui , Yang Junwei , Liu Yingxue Cathy , Zhang Zhizheng , Li Xiaoling , Zhang Weifeng , Zuo Li
Published: March 2024

Background

VS-505 (AP301), an acacia and ferric oxyhydroxide polymer, is a novel fiber-iron-based phosphate binder. This two-part Phase 2 study evaluated the tolerability, safety and efficacy of oral VS-505 administered three times daily with meals in treating hyperphosphatemia in chronic kidney disease (CKD) patients receiving maintenance hemodialysis (MHD).

Methods

In Part 1, patients received dose-escalated treatment with VS-505 2.25, 4.50 and 9.00 g/day for 2 weeks each, guided by serum phosphorus levels. In Part 2, patients received randomized, open-label, fixed-dosage treatment with VS-505 (1.50, 2.25, 4.50 or 6.75 g/day) or sevelamer carbonate 4.80 g/day for 6 weeks. The primary efficacy endpoint was the change in serum phosphorus.

Results

The study enrolled 158 patients (Part 1: 25; Part 2: 133), with 130 exposed to VS-505 in total. VS-505 was well tolerated. The most common adverse events were gastrointestinal disorders, mainly feces discolored (56%) and diarrhea (15%; generally during Weeks 1–2 of treatment). Most gastrointestinal disorders resolved without intervention, and none was serious. In Part 1, serum phosphorus significantly improved (mean change −2.0 mg/dL; 95% confidence interval −2.7, −1.4) after VS-505 dose escalation. In Part 2, serum phosphorus significantly and dose-dependently improved in all VS-505 arms, with clinically meaningful reductions with VS-505 4.50 and 6.75 g/day, and sevelamer carbonate 4.80 g/day [mean change −1.6 (−2.2, −1.0), −1.8 (−2.4, −1.2) and −1.4 (−2.2, −0.5) mg/dL, respectively]. In both parts, serum phosphorus reductions occurred within 1 week of VS-505 initiation, returning to baseline within 2 weeks of VS-505 discontinuation.

Conclusion

VS-505, a novel phosphate binder, was well tolerated with a manageable safety profile, and effectively and dose-dependently reduced serum phosphorus in CKD patients with hyperphosphatemia receiving MHD.

Clinical Trial registration number

NCT04551300
Physical exercise: a polypill against chronic kidney disease
Authors: Valenzuela Pedro L , Castillo-García Adrián , Saco-Ledo Gonzalo , Santos-Lozano Alejandro , Lucia Alejandro
Published: March 2024

We are currently facing a pandemic of physical inactivity that might contribute to the growing prevalence of chronic kidney disease (CKD). Here, we summarize currently available evidence on the association between physical activity and CKD, and also review the effects of exercise intervention in affected patients. Physical activity/exercise might act as a polypill against CKD, preventing its development or even exerting beneficial effects once it is established (i.e. improvements in patients’ physical fitness and cardiovascular risk, as well as in kidney function). Exercise benefits are also found at advanced CKD stages or in patients under hemodialysis. The biological mechanisms behind the clinical evidence are also discussed. An active lifestyle appears as a cornerstone in CKD prevention and management.
Executive summary of the American Radium Society appropriate use criteria for brain metastases in epidermal growth factor receptor mutated-mutated and ALK-fusion non-small cell lung cancer
Authors: Nagpal Seema , Milano Michael T , Chiang Veronica L , Soltys Scott G , Brackett Alexandria , Halasz Lia M , Garg Amit K , Sahgal Arjun , Ahluwalia Manmeet S , Tom Martin C , Palmer Joshua D , Knisely Jonathan P S , Chao Samuel T , Gephart Melanie Hayden , Wang Tony J C , Lo Simon S , Chang Eric L
Published: March 2024

The American Radium Society (ARS) Central Nervous System (CNS) committee reviewed literature on epidermal growth factor receptor mutated (EGFRm) and ALK-fusion (ALK+) tyrosine kinase inhibitors (TKIs) for the treatment of brain metastases (BrMs) from non-small cell lung cancers (NSCLC) to generate appropriate use guidelines addressing use of TKIs in conjunction with or in lieu of radiotherapy (RT). The panel developed three key questions to guide systematic review: can radiotherapy be deferred in patients receiving EGFR or ALK TKIs at (1) diagnosis or (2) recurrence? Should TKI be administered concurrently with RT (3)? Two literature searches were performed (May 2019 and December 2023). The panel developed 8 model cases and voted on treatment options using a 9-point scale, with 1–3, 4–6 and 7–9 corresponding to usually not appropriate, may be appropriate, and usually appropriate (respectively), per the UCLA/RAND Appropriateness Method. Consensus was achieved in only 4 treatment scenarios, all consistent with existing ARS-AUC guidelines for multiple BrM. The panel did not reach consensus that RT can be appropriately deferred in patients with BrM receiving CNS penetrant ALK or EGFR TKIs, though median scores indicated deferral may be appropriate under most circumstances. Whole brain RT with concurrent TKI generated broad disagreement except in cases with 2–4 BrM, where it was considered usually not appropriate. We identified no definitive studies dictating optimal sequencing of TKIs and RT for EGFRm and ALK+ BrM. Until such studies are completed, the committee hopes these cases guide decision- making in this complex clinical space.
Highly efficient nitrogen fixation over S-scheme heterojunction photocatalysts with enhanced active hydrogen supply
Authors: Bao Tong , Xi Yamin , Zhang Chaoqi , Du Peiyang , Xiang Yitong , Li Jiaxin , Yuan Ling , Yu Chengzhong , Liu Chao
Published: March 2024

Photocatalytic N2 fixation is a promising strategy for ammonia (NH3) synthesis; however, it suffers from relatively low ammonia yield due to the difficulty in the design of photocatalysts with both high charge transfer efficiency and desirable N2 adsorption/activation capability. Herein, an S-scheme CoSx/ZnS heterojunction with dual active sites is designed as an efficient N2 fixation photocatalyst. The CoSx/ZnS heterojunction exhibits a unique pocket-like nanostructure with small ZnS nanocrystals adhered on a single-hole CoSx hollow dodecahedron. Within the heterojunction, the electronic interaction between ZnS and CoSx creates electron-deficient Zn sites with enhanced N2 chemisorption and electron-sufficient Co sites with active hydrogen supply for N2 hydrogenation, cooperatively reducing the energy barrier for N2 activation. In combination with the promoted photogenerated electron-hole separation of the S-scheme heterojunction and facilitated mass transfer by the pocket-like nanostructure, an excellent N2 fixation performance with a high NH3 yield of 1175.37 μmol g−1 h−1 is achieved. This study provides new insights into the design of heterojunction photocatalysts for N2 fixation.
Job demands and DHEA-S levels: a study on healthcare workers
Authors: Marcatto F , Patriarca E , Bramuzzo D , Lucci E , Larese Filon F
Published: March 2024

Background

The intricate interplay between work-related stress and its physiological impact has drawn extensive research attention. Dehydroepiandrosterone sulphate (DHEA-S) emerges as a potential biomarker reflecting stress-related endocrine changes.

Aims

This cross-sectional study aimed to examine the association between job demands and DHEA-S levels among healthcare workers. The study also explored potential correlations between DHEA-S levels and psychophysical symptoms commonly linked to work-related stress.

Methods

A sample of 488 healthcare workers from a local health authority participated. Job demands were measured using the Demands scale of the Health and Safety Management Standards Indicator Tool. DHEA-S levels and symptom prevalence were assessed through serum analysis and questionnaires, respectively.

Results

Workers exposed to high job demands exhibited significantly lower DHEA-S levels compared to those with low job demands. Psychophysical symptoms, including sleep disorders, depression, and headache, were more prevalent in the high-demands group. DHEA-S levels showed significant negative correlations with the prevalence of all considered symptoms.

Conclusions

The study shows the inverse relationship between job demands and DHEA-S levels among healthcare workers, indicating that high job demands correlate with reduced DHEA-S secretion and increased symptom prevalence. The findings suggest DHEA-S as a potential biomarker for assessing the physiological consequences of work-related stress. Proactive interventions in managing job demands are crucial for promoting employee well-being and productivity in demanding work environments. By recognizing DHEA-S as a stress biomarker, organizations can effectively address stress-related health risks and implement targeted interventions for enhancing employees’ overall health and work performance.
The Unveiling of the Corona
Authors: Pasachoff Jay M.
Published: March 2024

The solar corona is visually the most striking feature of the eclipse. Governing many aesthetic representations, it also has a special place in the history of science. When the Sun is eclipsed, the occultation renders visible things that otherwise cannot be seen, leading to a better understanding of the properties and structure of the Sun’s atmosphere that is usually obscured by scattered sunlight. Studies of the solar corona have led to advances in atomic physics and a better understanding of ‘space weather,’ which originates in the solar atmosphere and interacts with the Earth’s magnetic field, to affect our lives here on Earth. There are still fundamental unanswered questions about the solar corona, which might be explored by space probes to the Sun and innovative solar telescopes.
Total Eclipse of the Art
Authors: Lange Henrike Christiane
Published: March 2024

Posing unique challenges in the history of representation, total solar eclipses involve all of the following: phenomena of movement, light, shadow, obfuscation, momentousness, and gradual dimming down and up as a process with a climactic moment at its centre—all happening on a massive scale and across inconceivable distances, requiring the combination of cosmic imagination with scientific understanding. Complicating things further, the central moment merges the visual cosmic spectacle above with its own dramatic effects on sky and land below. Finally, while the event above is predictable, the weather conditions in between are not—and the tension between hyper-predictable and entirely uncertain conditions of visibility add to the interest in the event’s historical–visual documentation as much as to the preciousness and awe of the actual experience. Combining perspectives from art and literary history, the following chapter focuses on total solar eclipse perception and representation (one of the common denominators across the visual and textual arts)—on word, image, media specificity, and a range of historical developments in which these representational challenges connect to central interdisciplinary questions of time, perception, and experience.
The Role of Crustal Contamination throughout the 1329–2005 CE Eruptive Record of Mt. Etna Volcano, Italy
Authors: Takach Marie K , Bohrson Wendy A , Spera Frank J , Viccaro Marco
Published: March 2024

The nearly continuous volcanic eruption record at Mt. Etna dating back ~700 years provides an excellent opportunity to investigate the geochemical evolution of a highly active volcano. Of particular interest is elucidating the cause of selective enrichment in alkali elements (K and Rb) and 87Sr/86Sr observed in various episodes of past activity. More recently, this alkali enrichment trend started to manifest in the 17th century and accelerated after 1971, and was accompanied by an increase in the volume, frequency, and explosivity of eruptions. Explanations for this signature include recharge of alkali-enriched magmas and/or crustal contamination from the subvolcanic basement. This study quantitatively examines the role of crustal contamination in post-1971 Etnean magma compositions via hundreds of open-system phase equilibria and trace element calculations based upon whole-rock major oxides, trace elements, 87Sr/86Sr ratios, and mineral compositional data. Available pre-1971 petrochemical data are satisfactorily reproduced by fractional crystallization of a high whole-rock MgO (12–17 wt.%), Ni (135–285 ppm), and Cr (920–1330 ppm) parental magma composition that is documented in Etna's ~4-ka fall-stratified deposit. Observed post-1971 whole-rock and glass trends and phase equilibria are reproduced via modeled assimilation of a skarn and flysch mixture, lithologies that represent the uppermost 10 to 15 km of sedimentary rocks beneath Etna. Notably, models show that K2O (wt.%) and Rb (ppm) behave incompatibly during partial melting of skarn/flysch. Additionally, the observed elevation of 87Sr/86Sr in post-1971 samples is consistent with the addition of radiogenic Sr from wallrock partial melts. In best-fit models, which yield observed post-1971 K2O, Rb, and 87Sr/86Sr trends, ~17% anatectic melt is assimilated and there may be a subordinate stoped wallrock component of ≤2% (percentage is relative to the starting mass of pristine magma). Previous work has shown that metasomatized spinel lherzolite and garnet pyroxenite can be melted in different proportions to reproduce long- and short-term changes observed in Etna’s geochemical products. We propose that the alkali enrichment signature observed after 1971 can be fully explained through the combination of mantle heterogeneity and crustal contamination. In particular, up to ~20% crustal input coupled with mantle heterogeneity of primitive melts explains the geochemical signals quite well. The influence of crustal contamination on post-1971 lavas is, in part, the result of frequent recharge of magmas that thermally primed the middle to upper crust and enhanced its partial melting.
Understanding decision curve analysis in clinical prediction model research
Authors: Zhao Luqing , Leng Yueshuang , Hu Yongbin , Xiao Juxiong , Li Qingling , Liu Chuyi , Mao Yitao
Published: March 2024

Background

Many medical graduate students lack a thorough understanding of decision curve analysis (DCA), a valuable tool in clinical research for evaluating diagnostic models.

Methods

This article elucidates the concept and process of DCA through the lens of clinical research practices, exemplified by its application in diagnosing liver cancer using serum alpha-fetoprotein levels and radiomics indices. It covers the calculation of probability thresholds, computation of net benefits for each threshold, construction of decision curves, and comparison of decision curves from different models to identify the one offering the highest net benefit.

Results

The paper provides a detailed explanation of DCA, including the creation and comparison of decision curves, and discusses the relationship and differences between decision curves and receiver operating characteristic curves. It highlights the superiority of decision curves in supporting clinical decision-making processes.

Conclusion

By clarifying the concept of DCA and highlighting its benefits in clinical decisionmaking, this article has improved researchers’ comprehension of how DCA is applied and interpreted, thereby enhancing the quality of research in the medical field.
Fiction as a defeater
Authors: Stokke Andreas
Published: March 2024

This paper argues that no instances of acquiring knowledge from works of literary fiction are instances of the way we ordinarily learn from the testimony of others. The paper argues that the fictional status of a work is a defeater for the justification of beliefs formed on the basis of statements within that work, which must itself be defeated for such beliefs based on fiction to amount to knowledge. This marks a fundamental difference with learning from testimony, since regardless of one's views on testimony and testimonial knowledge, the fact that your belief that p was based on someone's testimony that p is not in and of itself a defeater for your justification for believing that p.
Determining the primes of bad reduction of cm curves of genus 3
Authors: Ionica Sorina , KılıÇer Pınar , Lauter Kristin , Lorenzo GarcíA Elisa , MÂnzĂŢeanu Adelina , Vincent Christelle
Published: March 2024

In this paper, we introduce a new problem called the Isogenous Embedding Problem (IEP) and relate the existence of solutions to this problem to the primes of bad reduction of complex multiplication curves of genus 3. More precisely, the absence of solutions to IEP implies potentially good reduction. We propose an algorithm for computing the solutions to the IEP and run the algorithm through different families of curves. Using this algorithm, we were able to prove the reduction type of some particular curves at certain primes that were open cases in R. Lercier, Q. Liu, E. Lorenzo García and C. Ritzenthaler, Reduction type of smooth plane quartics, Algebra Number Theory  15 no. 6 2021, 1429–1468.
A patient-centred assessment of the 2016 ACR-EULAR Myositis Response Criteria: evaluating the meaningfulness of responses
Authors: Saygin Didem , Chandrasekhara Pillai Anjana , Moghadam-Kia Siamak , Oddis Chester V , Ren Dianxu , Najem Catherine , Dhatt Harman , Aggarwal Rohit
Published: March 2024

Objectives

The ACR-EULAR Myositis Response Criteria [Total Improvement Score (TIS)] is a composite measure calculated using changes in myositis core set measures. It is unclear if achieving improvement per TIS reflects improvement in any symptoms of patients with myositis. In this study, we examined the association between achieving TIS improvement and patient-centred outcome measures (PCOMs).

Methods

Adults with myositis were enrolled in a prospective study with baseline and 6-month visits. Six core set measures were collected at each visit along with the following PCOMs: fatigue [visual analogue scale (VAS) and short form 36 (SF36)], pain (VAS, SF36), health-related quality of life (SF-36), physical function (PROMIS-physical function, SF36, sit-to-stand, timed up-and-go and six-min walk) and physical activity (actigraphy). Mann–Whitney U was used to compare PCOMs between improvement groups. Spearman correlation and regression models were used for correlation and association between TIS and PCOMs, respectively.

Results

Of 50 patients (six polymyositis, 24 dermatomyositis, nine necrotizing myopathy, 11 anti-synthetase syndrome) enrolled (mean age: 52, 60% female), 21 patients satisfied the TIS improvement criteria at 6 months. PCOMs including fatigue, pain, quality of life, physical activity and physical function demonstrated significantly greater improvement in patients who had minimal TIS improvement compared with those with no improvement. Greater PCOM improvements were seen with moderate-major TIS improvement. TIS had moderate-strong correlations with most PCOMs.

Conclusion

Achieving improvement criteria was accompanied by significant clinical improvements in fatigue, pain, health-related quality of life, physical function, and physical activity. These results support the use of TIS as a clinically meaningful metric of improvement.
Characteristics associated with patient-reported treatment success in psoriatic arthritis
Authors: Samuel Christeen , Finney Amanda , Grader-Beck Thomas , Haque Uzma , Miller John , Grieb Suzanne M , Prichett Laura , Orbai Ana-Maria
Published: March 2024

Objectives

To determine characteristics associated with patient-reported treatment success in psoriatic arthritis (PsA).

Methods

Rheumatologist-diagnosed PsA patients fulfilling the CASPAR classification were recruited from a single center. PsA outcome measures included: 66/68 swollen/tender joint counts, Leeds/SPARCC dactylitis/enthesitis indices, psoriasis body surface area (BSA), and patient-reported outcomes (PROs) including PROMIS. The primary outcome was a patient-reported item: ‘Today, considering the level of control of your psoriatic arthritis and psoriasis, do you consider your treatment has been successful?’. Descriptive and multivariate logistic regression analyses identified clinical predictors of patient-reported treatment success. Patient-reported reasons for lack of treatment success were explored.

Results

A total of 178 participants had a baseline visit. Mean (SD) CASPAR score was 3.7 (0.9), age 51.7 (13.5) years, and BMI 31.3 (7.2) kg/m2. Fifty-two percent were women, and 86.0% white. Treatment success was reported by 116/178 (65%) patients in the analytic cohort. Among 76 patients who reported treatment failure, the most frequently selected reasons for lack of success were pain (n = 55, 72.4%), fatigue (n = 46, 60.5%), inflamed joints (n = 40, 52.6%) and stiffness (n = 40, 52.6%). Overall, 105 participants had complete data across variables in the logistic regression models. Patient-reported treatment success was independently associated with the 66-swollen/68-tender joint counts, psoriasis BSA, PROs (pain interference, physical function, fatigue) and TNF-inhibitor therapy, after controlling for BMI and demographics.

Conclusion

Patient-reported treatment success in PsA may be achieved through improvement of inflammatory arthritis, psoriasis, pain, physical function, fatigue and the use of TNF-inhibitors. Patients reported treatment failure was most commonly due to symptoms of pain, fatigue and stiffness.
Infrastructure and Structural Change in Africa
Authors: Dappe Matías Herrera , Lebrand Mathilde
Published: March 2024

Past investments in electricity, Internet, and road infrastructure, in isolation and bundled, have contributed to structural transformation and economic development in Africa. Using new data on the expansion of the road, electricity, and Internet networks over the past two decades, the paper shows that having access to both paved roads and electricity has led to a significant reallocation of labor from agricultural to both manufacturing and services. Adding access to fast Internet has had a major impact on structural change, with an even larger impact on reallocating labor away from agriculture. The paper then uses a spatial general-equilibrium model to quantify the impacts of future regional transport investments, bundled with electricity and Internet investments, on economic development in countries in the Horn of Africa and Lake Chad region.
Strangers and Foreigners: Trust and Attitudes toward Citizenship in Sub-Saharan Africa
Authors: Bertocchi Graziella , Dimico Arcangelo , Tedeschi Gian Luca
Published: March 2024

This study explores the factors that shape natives’ attitudes toward citizenship acquisition for foreigners. The hypothesis is that, in Sub-Saharan Africa, the slave trade represents a deep determinant of contemporary attitudes toward citizenship, through a proximate determinant which is the level of trust. Accordingly, individuals belonging to ethnic groups with higher exposure to historical slave exports are more likely to exhibit a sense of distrust toward strangers, and are consequently more likely to oppose citizenship laws that favor the inclusion of foreigners. The findings indicate that individuals with higher levels of trust toward other people do exhibit more favorable attitudes regarding the acquisition of citizenship at birth for children of foreigners, that these attitudes are also negatively related to the intensity of the slave trade, and that the underlying inverse relationship between trust and the slave trade is confirmed. Other factors such as conflict, kinship tightness, and witchcraft beliefs, which could also influence attitudes toward citizenship through the channel of trust, do not yield the same distinct pattern of associations as observed with the slave trade.
Prevalence of FRAC Group 11 Fungicide Resistance in Stemphylium vesicarium Isolates, but Not S. beticola Isolates, Causing Stemphylium Leaf Spot of Spinach (Spinacia oleracea)
Authors: Spawton Kayla A. , du Toit Lindsey J.
Published: March 2024

Stemphylium leaf spot of spinach, caused by Stemphylium beticola and S. vesicarium, is a disease of economic importance in fresh market, processing, and seed production. There have been increasing reports of difficulty managing the disease in the southern United States using fungicides in Fungicide Resistance Action Committee (FRAC) group 11. Isolates of S. beticola and S. vesicarium obtained from spinach leaves and seed from 2001 to 2020 were screened for resistance to azoxystrobin and pyraclostrobin in vitro, in vivo, and using PCR assays to detect mutations in cytochrome b associated with resistance in other fungi (F129L, G137R, and G143A). EC50 values for mycelial growth and conidial germination of S. vesicarium isolates in vitro were significantly less (mean of 0.35 μg/ml) than that of S. vesicarium (mean of 14.17 μg/ml) with both fungicides. All isolates were slightly more sensitive to pyraclostrobin than azoxystrobin in both assays. In vivo assays of plants inoculated with the isolates of S. vesicarium demonstrated poor efficacy of fungicides with each of the two active ingredients. Only the G143A mutation was detected in all spinach isolates of S. vesicarium, including an isolate of S. vesicarium collected in 2003 and 82.9% of isolates from spinach seed lots harvested from crops grown in or after 2017 in Europe, New Zealand, and the United States. The FRAC 11 mutations were not detected in any isolates of S. beticola. The in vitro, in vivo, and DNA mutation assays suggest FRAC group 11 fungicide resistance is widespread in spinach isolates of S. vesicarium but not S. beticola.
Transcriptome Study of Bursaphelenchus xylophilus Treated with Fomepizole Reveals a Serine/Threonine-Protein Phosphatase Gene that Is Substantially Linked with Vitality and Pathogenicity
Authors: Wang Linsong , Qin Chenglei , Guo Qunqun , Han Yi , Du Guicai , Li Ronggui
Published: March 2024

Bursaphelenchus xylophilus, the pine wood nematode (PWN), is the causal agent of pine wilt disease (PWD), which causes enormous economic loss annually. According to our previous research, fomepizole, as a selective inhibitor of PWN alcohol dehydrogenase (ADH), has the potential to be a preferable lead compound for developing novel nematicides. However, the underlying molecular mechanism is still unclear. The result of molecular docking showed that the stronger interactions between fomepizole and PWN ADH at the active site of ADH were attributed to hydrogen bonds. Low-dose fomepizole had a substantial negative impact on the egg hatchability, development, oviposition, and lifespan of PWN. Transcriptome analysis indicated that 2,124 upregulated genes and 490 downregulated genes in fomepizole-treated PWN were obtained. Kyoto Encyclopedia of Genes and Genomes enrichment analysis of differentially expressed genes indicated that fomepizole could be involved in controlling PWN vitality mainly by regulating key signaling pathways, such as the ribosome, hippo signaling pathway, and lysosome. Remarkably, the results of RNA interference indicated that the downregulated serine/threonine-protein phosphatase gene ( stpp) could reduce the egg hatchability, development, oviposition, and lifespan of PWN, which was closely similar to the consequences of nematodes with low-dose fomepizole treatment. In addition, the silencing of stpp resulted in weakness of PWN pathogenicity, which indicated that stpp could be a potential drug target to control PWN.
A New Look at Vertebral Body Tethering (VBT): Through the Modified Clavien-Dindo-Sink (mCDS) Classification
Authors: Vorhies John S. , Hauth Lucas , Garcia Samantha , Roye Benjamin D. , Poon Selina , Sturm Peter F. , Glotzbecker Michael , Fletcher Nicholas D. , Stone Joseph D. , Cahill Patrick J. ,   The Pediatric Spine Study Group, Anari Jason B.
Published: March 2024

Introduction:

Anterior vertebral body tethering (AVBT) is increasingly popular as an option for surgical treatment of idiopathic scoliosis (IS). While the technology remains new, it is important for families and patients to be able to compare it to the current standard of care, posterior spinal fusion (PSF). The purpose of this study is to describe the complication rate of AVBT in IS using the mCDS and to compare it to the recently reported complication rate of PSF in IS.

Methods:

A multicenter pediatric spine deformity database was queried for all idiopathic scoliosis patients who underwent vertebral body tethering. There were 171 patients with a minimum 9-month follow-up included in this study. Complications were retrospectively graded by 2 attending pediatric spine surgeons using the mCDS classification system.

Results:

Data from 171 patients with idiopathic scoliosis was available for analysis, with 156/171 (91%) of patients being female and an average age of 12.2 years old at surgery. There were 156 thoracic tethers (1 with an LIV below L2), 5 lumbar tethers, 9 staged double tethers, and only 1 patient with same-day double tether. Fifty-five (55) (32%) patients experienced a total of 69 complications. The most common complication type for VBT by mCDS was Grade IIIb, encompassing 29/69 (42%) of complications. The second most frequent complication grade was Grade I at 23/69 (33%). Thirty-four (34) out of 69 (49%) of the VBT complications reported required either procedural/surgical intervention or admission to the ICU.

Conclusions:

This is the first study to directly compare the complication profile of VBT to PSF using the mCDS. Forty-nine percent (49%) of the VBT complications reported were at least Grade III, while only 7% of complications in the control PSF cohort from the literature were Grade III or higher. The mCDS complication classification brings light to the early learning experience of a new technique compared to the widely accepted standard of PSF for IS.

Level of Evidence:

III – Retrospective comparative study.