bluuebunny/crossref_metadata_2025 huggingface dataset:
New frontiers for qualitative textual data analysis: a multimethod statistical approach
Authors: Figura Mariachiara , Fraire Mary , Durante Angela , Cuoco Angela , Arcadi Paola , Alvaro Rosaria , Vellone Ercole , Piervisani Loredana
Published: February 2023

In recent years, the increase in textual data production has meant that researchers require faster text analysis techniques and software to reliably produce knowledge for the scientific–nursing community. Automatic text data analysis opens the frontiers to a new research area combining the depth of analysis typical of qualitative research and the stability of measurements required for quantitative studies. Thanks to the statistical–computational approach, it proposes to study more or less extensive written texts produced in natural language to reveal lexical and linguistic worlds and extract useful and meaningful information for researchers. This article aims to provide an overview of this methodology, which has been rarely used in the nursing community to date.
The relationship between symptom perception and fear of progression in patients with chronic heart failure: a multiple mediation analysis
Authors: Xiong Juanjuan , Qin Jingwen , Zheng Guixiang , Gao Ya , Gong Kaizheng
Published: February 2023

Aims

Studies have shown that symptom perception is associated with fear of progression (FOP) in many diseases and regulated by psychological factors. Whether the association also occurs in patients with chronic heart failure (HF) remains unclear, as do the specific mechanisms involved. This study aimed to explore the multiple mediation effects of self-care confidence and mental resilience on the relationship between symptom perception and FOP in Chinese patients with chronic HF.

Methods and results

A cross-sectional study was conducted on 247 patients with chronic HF recruited from two hospitals in Yangzhou, China. The sociodemographic and clinical data and self-reported questionnaires including heart failure somatic perception, fear of progression, self-care confidence, and mental resilience were collected. Data analysis relating to correlations and mediating effects was carried out by SPSS 26.0 and PROCESS v3.3 macro. Fear of progression was positively correlated with symptom perception (r = 0.599, P < 0.01), but negatively correlated with self-care confidence (r = −0.663, P < 0.01), mental resilience-strength (r = −0.521, P < 0.01), and mental resilience-toughness (r = −0.596, P < 0.01). The relationship between symptom perception and FOP was mediated by self-care confidence [effect = 0.095, 95% confidence interval (CI) (0.054–0.142)] and mental resilience-toughness [effect = 0.033, 95% CI (0.006–0.074)], respectively, and together in serial [effect = 0.028, 95% CI (0.011–0.050)]. The proportion of the mediating effect accounting for the total effect was 31.0%.

Conclusion

Self-care confidence and mental resilience-toughness were multiple mediators of the association between symptom perception and FOP in patients with chronic HF. Interventions targeted at strengthening self-care confidence and mental resilience may be beneficial for the reduction of FOP, especially with regard to toughness.
Under-representation of ethnic and regional minorities in lipid-lowering randomized clinical trials: a systematic review and meta-analysis
Authors: Sawant Sonia , Wang Nelson
Published: February 2023

Aims

The efficacy of lipid-lowering therapies (LLT) amongst different ethnicities and regions remains unclear. We aimed to assess cardiovascular event reductions associated with LLT according to ethnicity and region in previously published randomized clinical trials (RCTs).

Methods and results

Medline, EMBASE, and Cochrane CENTRAL were searched for RCTs of statins, ezetimibe, or proprotein convertase subtilisin/kexin type 9 inhibitors comparing intensive vs. less-intensive low-density lipoprotein cholesterol (LDL-C) lowering. The primary endpoint was major adverse cardiovascular events (MACE) defined as the composite of cardiovascular mortality, myocardial infarction, stroke, and revascularization. Random-effects meta-analysis was used to pool risk ratios (RRs) with 95% confidence intervals (CI) adjusted per mmol/L reduction in LDL-C. Fifty-three trials with 329 897 participants were included. Amongst participants, 39.5% were from Europe, 16.0% from North America, 9.0% from Japan, 2.8% from Australasia, 1.8% from South America, 1.1% from Asia, 0.6% from South Africa, and 29.2% were unspecified. Amongst trials reporting ethnicities, there were 60.3% White, 20.2% Japanese, 9.4% Asian, 5.5% Black, and 4.7% Latin American. There was reduction in MACE with LLT in regions including Australasia (RR 0.75, 95% CI 0.67–0.85), North America (RR 0.75, 95% CI 0.69–0.83), Europe (RR 0.78, 95% CI 0.71–0.86), and Japan (RR 0.73, 95% CI 0.63–0.85) and in Black ethnicity (RR 0.55, 95% CI 0.37–0.82). Head-to-head comparisons between regions and ethnicities revealed no significant differences in MACE reduction.

Conclusion

Despite under-representation in clinical trials, regional and ethnic minority groups such as Australasia and Blacks appear to derive at least as much cardiovascular benefit from LLT.
Non-invasive stereotactic arrhythmia radiotherapy for ventricular tachycardia: results of the prospective STARNL-1 trial
Authors: van der Ree Martijn H , Dieleman Edith M T , Visser Jorrit , Planken R Nils , Boekholdt S Matthijs , de Bruin-Bon Rianne H A , Rasch Coen R N , Hoeksema Wiert F , de Jong Rianne M A J , Kemme Michiel J B , Balt Jippe C , Wilde Arthur A M , Balgobind Brian V , Postema Pieter G
Published: February 2023

Aims

Stereotactic arrhythmia radiotherapy (STAR) is suggested as potentially effective and safe treatment for patients with therapy-refractory ventricular tachycardia (VT). However, the current prospective knowledge base and experience with STAR is limited. In this study we aimed to prospectively evaluate the efficacy and safety of STAR.

Methods and results

The StereoTactic Arrhythmia Radiotherapy in the Netherlands no.1 was a pre-post intervention study to prospectively evaluate efficacy and safety of STAR. In patients with therapy-refractory VT, the pro-arrhythmic region was treated with a 25 Gy single radiotherapy fraction. The main efficacy measure was a reduction in the number of treated VT-episodes by ≥50%, comparing the 12 months before and after treatment (or end of follow-up, excluding a 6-week blanking period). The study was deemed positive when ≥50% of patients would meet this criterion. Safety evaluation included left ventricular ejection fraction, pulmonary function, and adverse events. Six male patients with an ischaemic cardiomyopathy were enrolled, and median age was 73 years (range 54–83). Median left ventricular ejection fraction was 38% (range 24–52). The median planning target volume was 187 mL (range 93–372). Four (67%) patients completed the 12-month follow-up, and two patients died (not STAR related) during follow-up. The main efficacy measure of ≥50% reduction in treated VT-episodes at the end of follow-up was achieved in four patients (67%). The median number of treated VT-episodes was reduced by 87%. No reduction in left ventricular ejection fraction or pulmonary function was observed. No treatment related serious adverse events occurred.

Conclusions

STAR resulted in a ≥ 50% reduction in treated VT-episodes in 4/6 (67%) patients. No reduction in cardiac and pulmonary function nor treatment-related serious adverse events were observed during follow-up.

Clinical trial registration

Netherlands Trial Register—NL7510.
Populist Leadership, Opportunistic Decision-Making, and Poliheuristic Theory: Cristina Kirchner's Decision to Defy “The Vultures”
Authors: Fouquet Stephan
Published: February 2023

This study asks how two typically observed empirical manifestations across cases of international populist agency—issue-specific mass mobilization and personalistic decision-making—operate within politicized decision contexts to produce foreign policy outputs. Integrating a political-strategic conceptualization of populism with poliheuristic theory (PH), it is argued that the definitional components of populist leadership imply a particular inclination toward opportunistic decision-making. While PH suggests that most chief executives rely on heuristic option rejection but finally switch to more analytic option selection, the logic of political-strategic populism could enable and compel leaders to make entirely heuristic choices with a non-compensatory focus on domestic political constraints and opportunities. The plausibility of this proposition is probed with a theory-testing process-tracing of the Argentine President Cristina Fernández de Kirchner's decision to defy holdout creditors in a polarizing sovereign debt litigation. The results indicate more potential to analyze within-case mechanisms through which populism influences decision-making processes and outcomes.
A high-quality reference genome for the fission yeast Schizosaccharomyces osmophilus
Authors: Jia Guo-Song , Zhang Wen-Cai , Liang Yue , Liu Xi-Han , Rhind Nicholas , Pidoux Alison , Brysch-Herzberg Michael , Du Li-Lin
Published: February 2023

Fission yeasts are an ancient group of fungal species that diverged from each other from tens to hundreds of million years ago. Among them is the preeminent model organism Schizosaccharomyces pombe, which has significantly contributed to our understandings of molecular mechanisms underlying fundamental cellular processes. The availability of the genomes of S. pombe and 3 other fission yeast species S. japonicus, S. octosporus, and S. cryophilus has enabled cross-species comparisons that provide insights into the evolution of genes, pathways, and genomes. Here, we performed genome sequencing on the type strain of the recently identified fission yeast species S. osmophilus and obtained a complete mitochondrial genome and a nuclear genome assembly with gaps only at rRNA gene arrays. A total of 5,098 protein-coding nuclear genes were annotated and orthologs for more than 95% of them were identified. Genome-based phylogenetic analysis showed that S. osmophilus is most closely related to S. octosporus and these 2 species diverged around 16 million years ago. To demonstrate the utility of this S. osmophilus reference genome, we conducted cross-species comparative analyses of centromeres, telomeres, transposons, the mating-type region, Cbp1 family proteins, and mitochondrial genomes. These analyses revealed conservation of repeat arrangements and sequence motifs in centromere cores, identified telomeric sequences composed of 2 types of repeats, delineated relationships among Tf1/sushi group retrotransposons, characterized the evolutionary origins and trajectories of Cbp1 family domesticated transposases, and discovered signs of interspecific transfer of 2 types of mitochondrial selfish elements.
Three-dimensional inversion of semi-airborne electromagnetic data with a second-order finite-element forward solver
Authors: Rochlitz Raphael , Becken Michael , Günther Thomas
Published: February 2023

The analysis of controlled-source electromagnetic (EM) data recorded with semi-airborne exploration systems requires advanced simulation and inversion tools that are capable of handling realistic survey geometries. Semi-airborne EM setups with elongated transmitters deployed in mountainous terrain prohibit the exploitation of secondary-field formulations in numerical approximations without producing hardly quantifiable errors. Building upon the open-source software custEM for forward modeling and pyGIMLi for geophysical inversion, we present an inverse modeling procedure based on highly accurate second-order finite-element forward solutions on irregular grids and fast-converging Gauss–Newton minimization. Using the total-field formulation of the electric field approach in combination with a direct solver enables calculating explicit sensitivities with comparatively cheap back-substitutions for thousands of ground and airborne receiver stations in multiple flight areas. Second-order basis functions show general superiority over first-order basis-functions regarding the accuracy and performance of the forward problem. Beyond that, synthetic and real data inversion studies related to semi-airborne geometries indicate that second-order basis functions help particularly to avoid high modeling errors for the weakest field components and artifacts in the vicinity of transmitters or at the surface. This leads generally to a better convergence and final inversion results of higher robustness and quality. The presented tools are freely available such as the underlying software.
Subcontinental lithospheric mantle discontinuities beneath the Eastern Himalayan Plate Boundary System, NE India
Authors: Chaudhury Jashodhara , Mitra Supriyo
Published: February 2023

We use P-wave receiver function (P-RF) analysis and joint inversion with Rayleigh wave group velocity dispersion data to model the shear wave velocity (Vs) structure of subcontinental lithospheric mantle (SCLM) discontinuities beneath northeast (NE) India. The most prominent SCLM discontinuity is the Hales Discontinuity (H-D) observed beneath the Eastern Himalayan Foreland Basin (Brahmaputra Valley) and Shillong Plateau. The P-to-SV converted phase from the H-D (Phs) is a positive amplitude arrival at ∼10–12 s and has positive moveout with increasing ray-parameter. From joint inversion, the H-D is modelled at a depth range of 90–106 km, with 11–12 per cent Vs increase beneath the Brahmaputra Valley. Beneath the Shillong Plateau the H-D is at a depth range of 86–99 km, with 6–10 per cent Vs increase. An intralithospheric discontinuity (ILD) has been identified in the Shillong Plateau station P-RFs, as a positive amplitude PILDs phase, arriving at 8–8.5 s. This is modelled at a depth range of 66–75 km with Vs increase of 2–9 per cent. We construct 2-D profiles of depth-migrated common-conversion-point stack of P-RFs to distinguish the SCLM discontinuity arrivals from crustal phases. 3-D spline-interpolated surface of the H-D has been constructed to visualize its lateral variations. We use xenolith data from the Dharwar Craton, which has similar geological age, petrology and seismic structure as the Shillong Plateau, to petrologically model the SCLM H-D and ILD Vs structure in NE-India. From the calculated Vs structure we conjecture that the H-D is a petrological boundary between mantle peridotite and kyanite-eclogite, with its origin as metamorphosed paleosubducted oceanic slab, similar to other global observations. We further speculate that the shallower ILD could be formed as a contact between frozen asthenosphere-derived metasomatic melts within the SCLM.
Acid ceramidase involved in pathogenic cascade leading to accumulation of α-synuclein in iPSC model ofGBA1-associated Parkinson’s disease
Authors: Kumar Manoj , Srikanth Manasa P , Deleidi Michela , Hallett Penelope J , Isacson Ole , Feldman Ricardo A
Published: February 2023

Bi-allelic mutations in GBA1, the gene that encodes β-glucocerebrosidase (GCase), cause Gaucher disease (GD), whereas mono-allelic mutations do not cause overt pathology. Yet mono- or bi-allelic GBA1 mutations are the highest known risk factor for Parkinson’s disease (PD). GCase deficiency results in the accumulation of glucosylceramide (GluCer) and its deacylated metabolite glucosylsphingosine (GluSph). Brains from patients with neuronopathic GD have high levels of GluSph, and elevation of this lipid in GBA1-associated PD has been reported. To uncover the mechanisms involved in GBA1-associated PD, we used human induced pluripotent stem cell-derived dopaminergic (DA) neurons from patients harboring heterozygote mutations in GBA1 (GBA1/PD–DA neurons). We found that compared with gene-edited isogenic controls, GBA1/PD–DA neurons exhibit mammalian target of rapamycin complex 1 (mTORC1) hyperactivity, a block in autophagy, an increase in the levels of phosphorylated α-synuclein (129) and α-synuclein aggregation. These alterations were prevented by incubation with mTOR inhibitors. Inhibition of acid ceramidase, the lysosomal enzyme that deacylates GluCer to GluSph, prevented mTOR hyperactivity, restored autophagic flux and lowered α-synuclein levels, suggesting that GluSph was responsible for these alterations. Incubation of gene-edited wild type (WT) controls with exogenous GluSph recapitulated the mTOR/α-synuclein abnormalities of GBA1/PD neurons, and these phenotypic alterations were prevented when GluSph treatment was in the presence of mTOR inhibitors. We conclude that GluSph causes an aberrant activation of mTORC1, suppressing normal lysosomal functions, including the clearance of pathogenic α-synuclein species. Our results implicate acid ceramidase in the pathogenesis of GBA1-associated PD, suggesting that this enzyme is a potential therapeutic target for treating synucleinopathies caused by GCase deficiency.
Genome-wide association study identifies novel candidate malaria resistance genes in Cameroon
Authors: Esoh Kevin K , Apinjoh Tobias O , Amambua-Ngwa Alfred , Nyanjom Steven G , Chimusa Emile R , Amenga-Etego Lucas , Wonkam Ambroise , Achidi Eric A
Published: February 2023

Recent data suggest that only a small fraction of severe malaria heritability is explained by the totality of genetic markers discovered so far. The extensive genetic diversity within African populations means that significant associations are likely to be found in Africa. In their series of multi-site genome-wide association studies (GWAS) across sub-Saharan Africa, the Malaria Genomic Epidemiology Network (MalariaGEN) observed specific limitations and encouraged country-specific analyses. Here, we present findings of a GWAS of Cameroonian participants that contributed to MalariaGEN projects (n = 1103). We identified protective associations at polymorphisms within the enhancer region of CHST15 [Benjamin–Hochberg false discovery rate (FDR) < 0.02] that are specific to populations of African ancestry, and that tag strong eQTLs of CHST15 in hepatic cells. In-silico functional analysis revealed a signature of epigenetic regulation of CHST15 that is preserved in populations in historically malaria endemic regions, with haplotype analysis revealing a haplotype that is specific to these populations. Association analysis by ethnolinguistic group identified protective associations within SOD2 (FDR < 0.04), a gene previously shown to be significantly induced in pre-asymptomatic malaria patients from Cameroon. Haplotype analysis revealed substantial heterogeneity within the beta-like globin (HBB) gene cluster amongst the major ethnic groups in Cameroon confirming differential malaria pressure and underscoring age-old fine-scale genetic structure within the country. Our findings revealed novel insights in the evolutionary genetics of populations living in Cameroon under malaria pressure with new significant protective loci (CHST15 and SOD2) and emphasized the significant attenuation of genetic association signals by fine-scale genetic structure.
Admissible Homomorphisms and Equivariant Relations Between Weighted Projective Lines
Authors: Chen Jianmin , Lin Yanan , Ruan Shiquan , Zhang Hongxia
Published: February 2023

The string group acts on the category of coherent sheaves over a weighted projective line by degree-shift actions. We study the equivariant relations induced by degree-shift actions between weighted projective lines. We prove that such an equivariant relation is characterized by an admissible homomorphism between the associated string groups. We classify all these equivariant relations for the weighted projective lines of domestic and tubular types, respectively.
The cofactors and domains of a staphylococcal capsule-producing enzyme preserve its structure, stability, shape and dimerization ability
Authors: Chakraborty Tushar , Banerjee Nilanjan , Sinha Debasmita , Seal Soham , Chatterjee Subhrangsu , Sau Subrata
Published: February 2023

CapF, a staphylococcal capsule-producing enzyme, binds Zn2+ ion and NADPH using its C-terminal domain (CTD) and N-terminal domain (NTD), respectively. To elucidate the roles of cofactors and domains, we have systematically investigated the related recombinant proteins, rCapF, rCTD, recombinant NTD (rNTD) and the Zn2+-free rCapF/rCTD, Apo-rCapF/Apo-rCTD. The results show that the secondary structure, tertiary structure, shape and surface hydrophobicity of Apo-rCapF and Apo-rCTD are different from those of rCapF and rCTD. The removal of Zn2+ made rCapF thermo-sensitive, whereas both rCTD and Apo-rCTD are thermo-resistant proteins. Further, Apo-rCapF and rCapF existed as the dimers, whereas rCTD and Apo-rCTD formed a mixture of dimers and tetramers in the aqueous solution. Zn2+ maintained the structure of NTD as well. The NADPH binding activity and Cys accessibility of rNTD, rCapF and Apo-rCapF were significantly different from each other. The binding of NADPH to the above three proteins freely occurred, liberated heat at 25°C and increased their diameters. In addition, the structure, stability, shape and oligomerization ability of rNTD, rCTD and rCapF little resembled each other. Collectively, the domains and cofactors of CapF contribute to preserving its conformation, stability, shape and dimerization ability.
Valentino’s syndrome: a bizarre clinical presentation
Authors: Machaku Dennis , Suleman Mujaheed , Mduma Elias , Nkoronko Mugisha
Published: February 2023

A perforated peptic or duodenal ulcer may cause an unusual expression of right lower quadrant pain. In Valentino’s syndrome, the chemical fluid from the ulcer flows via the right paracolic gutter to the right iliac fossa, causing peritoneal irritation and chemical appendicitis which will mimic pain in the right lower quadrant. We report a case of a 23-year-old male patient who presented with cramping lower abdominal pain with fevers and vomiting. His pain was mostly in the right lower quadrant and radiated to his back. A perforation-related pneumoperitoneum was found on a computed tomography scan, along with an accumulation of fluid in the abdomen and thickening of the pyloric antrum. Valentino’s syndrome’s aberrant clinical picture mimicking acute appendicitis is a pathognomonic presentation of the disease. Right lower abdominal pain should also prompt the scrutiny of atypical differentials, such as perforated ulcers. Physicians need to manage these patients with a high index of suspicion.
The wheat basic helix-loop-helix gene TabHLH123 positively modulates the formation of crown roots and is associated with plant height and 1000-grain weight under various conditions
Authors: Wang Jinping , Li Chaonan , Mao Xinguo , Wang Jingyi , Li Long , Li Jialu , Fan Zipei , Zhu Zhi , He Liheng , Jing Ruilian
Published: February 2023

Crown roots are the main components of the fibrous root system in cereal crops and play critical roles in plant adaptation; however, the molecular mechanisms underlying their formation in wheat (Triticum aestivum) have not been fully elucidated. In this study, we identified a wheat basic helix-loop-helix (bHLH) protein, TabHLH123, that interacts with the essential regulator of crown root initiation, MORE ROOT in wheat (TaMOR). TabHLH123 is expressed highly in shoot bases and roots. Ectopic expression of TabHLH123 in rice resulted in more roots compared with the wild type. TabHLH123 regulates the expression of genes controlling crown-root development and auxin metabolism, responses, and transport. In addition, we analysed the nucleotide sequence polymorphisms of TabHLH123s in the wheat genome and identified a superior haplotype, TabHLH123-6B, that is associated with high root dry weight and 1000-grain weight, and short plant height. Our study reveals the role of TabHLH123 in controlling the formation of crown roots and provides beneficial insights for molecular marker-assisted breeding in wheat.
The galaxy formation origin of thelensing is lowproblem
Authors: Chaves-Montero Jonás , Angulo Raul E , Contreras Sergio
Published: February 2023

Recent analyses show that ΛCDM-based models optimized to reproduce the clustering of massive galaxies overestimate their gravitational lensing by about 30 per cent, the so-called lensing is low problem. Using a state-of-the-art hydrodynamical simulation, we show that this discrepancy reflects shortcomings in standard galaxy–halo connection models rather than tensions within the ΛCDM paradigm itself. Specifically, this problem results from ignoring a variety of galaxy formation effects, including assembly bias, segregation of satellite galaxies relative to dark matter, and baryonic effects on the matter distribution. All these effects contribute towards overestimating gravitational lensing, and when combined, explain the amplitude and scale dependence of the lensing is low problem. We conclude that simplistic galaxy–halo connection models are inadequate to interpret clustering and lensing simultaneously, and that it is crucial to employ more sophisticated models for the upcoming generation of large-scale surveys.
Modelling photometric reverberation mapping data for the next generation of big data surveys. Quasar accretion discs sizes with the LSST
Authors: Pozo Nuñez F , Bruckmann C , Deesamutara S , Czerny B , Panda S , Lobban A P , Pietrzyński G , Polsterer K L
Published: February 2023

Photometric reverberation mapping can detect the radial extent of the accretion disc (AD) in Active Galactic Nuclei by measuring the time delays between light curves observed in different continuum bands. Quantifying the constraints on the efficiency and accuracy of the delay measurements is important for recovering the AD size-luminosity relation, and potentially using quasars as standard candles. We have explored the possibility of determining the AD size of quasars using next-generation Big Data surveys. We focus on the Legacy Survey of Space and Time (LSST) at the Vera C. Rubin Observatory, which will observe several thousand quasars with the Deep Drilling Fields and up to 10 million quasars for the main survey in six broadband filter during its 10-yr operational lifetime. We have developed extensive simulations that take into account the characteristics of the LSST survey and the intrinsic properties of the quasars. The simulations are used to characterize the light curves from which AD sizes are determined using various algorithms. We find that the time delays can be recovered with an accuracy of 5 and 15 per cent for light curves with a time sampling of 2 and 5 d, respectively. The results depend strongly on the redshift of the source and the relative contribution of the emission lines to the bandpasses. Assuming an optically thick and geometrically thin AD, the recovered time-delay spectrum is consistent with black hole masses derived with 30 per cent uncertainty.
The Multi-band Survey Telescope at Zhongshan Station, Antarctica
Authors: Chen Chao , Li Zhengyang , Yang Chenwei , Han Zijian , Jiang Xin , Liu Tingting , Yuan Xiangyan , Jiang Peng , Ji Tuo , Yao Xu , Chen Mingfei
Published: February 2023

The Antarctic Plateau is considered to be the best ground-based astronomical site on Earth. Compared with other middle latitude observatories, the telescopes located in Antarctica have unique advantages in seeing a large fraction of clear nights, continuous observing window in the polar night, and so on. China has operated several generations of telescopes in Antarctica, but has not yet achieved multicolour simultaneous observation with tracking. Multi-band Survey Telescope (MST) is the first multicolour simultaneous survey telescope in Antarctica. It adopts a Newtonian telescope structure which is different from other Antarctic telescopes and is matched with a new alignment scheme suitable for the harsh environment of Antarctica. In addition, MST is equipped with a defrosting indium tin oxide (ITO) window and a high-precision equatorial mount. This paper introduces the optical design, mechanical structure, and analysis of the actual operation of MST in Antarctica. Since March 2022, MST has been carrying out the observation normally in Zhongshan Station, and the operation of MST has provided a new experience for the follow-up design and installation of Antarctic telescopes. We plan to further optimize the design and manufacture of MST, and develop it as a standard model of small-aperture Antarctic telescopes for space debris observations and time-domain surveys.
Simulating the deposition of angular momentum by jets in common envelope evolution
Authors: Schreier Ron , Hillel Shlomi , Soker Noam
Published: February 2023

We conducted 3D hydrodynamical simulations of common envelope evolution (CEE) of a neutron star (NS) or a black hole (BH) inside a red supergiant (RSG) envelope and find that the jets that we expect the NS/BH to launch during the CEE spin-up the common envelope. We find that when the NS/BH launches jets that are exactly perpendicular to the orbital plane (the jets are aligned with the orbital angular momentum) the jets deposit angular momentum to the envelope that is aligned with the orbital angular momentum. When the jets’ axis is inclined to the orbital angular momentum axis, so is the angular momentum that the jets deposit to the envelope. Such tilted jets might be launched when the NS/BH has a close companion when it enters the RSG envelope. We did not allow for spiralling-in and could follow the evolution for only three orbits. The first orbit mimics the plunge-in phase of the CEE, when the NS/BH rapidly dives in, while the third orbit mimics the self-regulated phase when spiralling-in is very slow. We find that the jets deposit significant amount of angular momentum only during the plunge-in phase. A post-CEE core collapse supernova explosion will leave two NS/BH, bound or unbound, whose spin might be misaligned to the orbital angular momentum. Our results strengthen an earlier claim that inclined-triple-star CEE might lead to spin-orbit misalignment of NS/BH-NS/BH binary systems.
Monitoring observations of SMC X-1’s excursions (MOOSE)  – II. A new excursion accompanies spin-up acceleration
Authors: Hu Chin-Ping , Dage Kristen C , Clarkson William I , Brumback McKinley , Charles Philip A , Haggard Daryl , Hickox Ryan C , Mihara Tatehiro , Bahramian Arash , Karam Rawan , Athukoralalage Wasundara , Altamirano Diego , Neilsen Joey , Kennea Jamie
Published: February 2023

SMC X-1 is a high-mass X-ray binary showing superorbital modulation with an unstable period. Previous monitoring shows three excursion events in 1996–1998, 2005–2007, and 2014–2016. The superorbital period drifts from ≳60 to ≲40 d and then evolves back during an excursion. Here, we report a new excursion event of SMC X-1 in 2020–2021, indicating that the superorbital modulation has an unpredictable, chaotic nature. We trace the spin-period evolution and find that the spin-up rate accelerated 1 yr before the onset of this new excursion, which suggests a possible inside-out process connecting the spin-up acceleration and the superorbital excursion. This results in a deviation of the spin-period residual, similar to the behaviour of the first excursion in 1996–1998. In further analysis of the pulse profile evolution, we find that the pulsed fraction shows a long-term evolution and may be connected to the superorbital excursion. These discoveries deepen the mystery of SMC X-1 because they cannot be solely interpreted by the warped-disc model. Upcoming pointed observations and theoretical studies may improve our understanding of the detailed accretion mechanisms taking place.
Lognormal seminumerical simulations of the Lyman α forest: comparison with full hydrodynamic simulations
Authors: Arya Bhaskar , Choudhury Tirthankar Roy , Paranjape Aseem , Gaikwad Prakash
Published: February 2023

Observations of the Lyman α (Ly α) forest in spectra of distant quasars enable us to probe the matter power spectrum at relatively small scales. With several upcoming surveys, it is expected that there will be a many-fold increase in the quantity and quality of data, and hence it is important to develop efficient simulations to forward model these data sets. One such seminumerical method is based on the assumption that the baryonic densities in the intergalactic medium (IGM) follow a lognormal distribution. In this work, we test the robustness of the lognormal model of the Ly α forest in recovering a set of IGM parameters by comparing with high-resolution Sherwood smoothed particle hydrodynamics (SPH) simulations. We study the recovery of the parameters T0 (temperature of the mean-density IGM), γ (slope of the temperature–density relation), and Γ12 (hydrogen photoionization rate) at z ∼ 2.5 using a Markov chain Monte Carlo technique for parameter estimation. Using three flux statistics, the probability distribution, the mean flux, and the power spectrum, values of all three parameters, T0, γ, and Γ12, implied in the SPH simulations are recovered within 1 − σ (∼9, 4, and 1 per cent, respectively) of the median (best-fitting) values. We verify the validity of our results at different baryon smoothing filter, signal-to-noise ratio, box size and resolution, and data seed and confirm that the lognormal model can be used as an efficient tool for modelling the Ly α transmitted flux at z ∼ 2.5.
Spectroscopy of CASSOWARY gravitationally lensed galaxies in SDSS: characterization of an extremely bright reionization-era analogue at z = 1.42
Authors: Mainali Ramesh , Stark Daniel P , Jones Tucker , Ellis Richard S , Hezaveh Yashar D , Rigby Jane R
Published: February 2023

We present new observations of 16 bright (r = 19–21) gravitationally lensed galaxies at z ≃ 1–3 selected from the CASSOWARY survey. Included in our sample is the z = 1.42 galaxy CSWA-141, one of the brightest known reionization-era analogues at high redshift (g = 20.5), with a large specific star formation rate (31.2 Gyr−1) and an [O iii]+H β equivalent width (EW[O iii] + H β = 730 Å) that is nearly identical to the average value expected at z ≃ 7–8. In this paper, we investigate the rest-frame UV nebular line emission in our sample with the goal of understanding the factors that regulate strong C iii] emission. Although most of the sources in our sample show weak UV line emission, we find elevated C iii] in the spectrum of CSWA-141 (EWC iii] = 4.6 ± 1.9 Å) together with detections of other prominent emission lines (O iii], Si iii], Fe ii⋆, Mg ii). We compare the rest-optical line properties of high-redshift galaxies with strong and weak C iii] emission, and find that systems with the strongest UV line emission tend to have young stellar populations and nebular gas that is moderately metal-poor and highly ionized, consistent with trends seen at low and high redshift. The brightness of CSWA-141 enables detailed investigation of the extreme emission line galaxies which become common at z > 6. We find that gas traced by the C iii] doublet likely probes higher densities than that traced by [O ii] and [S ii]. Characterization of the spectrally resolved Mg ii emission line and several low-ionization absorption lines suggests neutral gas around the young stars is likely optically thin, potentially facilitating the escape of ionizing radiation.
Correcting bandwidth depolarization by extreme Faraday rotation
Authors: Fine Maxwell A , Van Eck Cameron L , Pratley Luke
Published: February 2023

Measurements of the polarization of radio emission are subject to a number of depolarization effects such as bandwidth depolarization, which is caused by the averaging effect of a finite channel bandwidth combined with the frequency-dependent polarization caused by Faraday rotation. There have been very few mathematical treatments of bandwidth depolarization, especially in the context of the rotation measure (RM) synthesis method for analysing radio polarization data. We have found a simple equation for predicting if bandwidth depolarization is significant for a given observational configuration. We have derived and tested three methods of modifying RM synthesis to correct for bandwidth depolarization. From these tests we have developed a new algorithm that can detect bandwidth-depolarized signals with higher signal-to-noise ratio than conventional RM synthesis and recover the correct source polarization properties (RM and polarized intensity). We have verified that this algorithm works as expected with real data from the LOw-Frequency ARray (LOFAR) Two-metre Sky Survey. To make this algorithm available to the community, we have added it as a new tool in the RM-Tools polarization analysis package.
Regulating Big Tech: the role of enhanced disclosures
Authors: Mazzucato Mariana , Strauss Ilan , O’Reilly Tim , Ryan-Collins Josh
Published: February 2023

Attempts by governments to curb the market power of ‘Big Tech’ (Alphabet, Amazon, Apple, Meta Platforms, and Microsoft) are impeded by limited public information on their diversified digital platform ecosystems. Big Tech’s annual 10-K financial reports disclose little about their globally dominant ‘free’ services, platform user numbers, and monetization practices, and suites of products. To support antitrust and regulatory oversight, we propose mandatory 10-K type disclosures covering Big Tech’s: (i) internally used operating metrics (e.g. monthly active users), which underpin platform market share and monetization; (ii) ubiquitous ‘free’ products which escape traditional ‘profit and loss’ reporting; (iii) ‘monetization’ processes detailing how platforms make money from user data and attention; and (iv) product-by-product reporting through updating segment reporting rules. Disclosures should be mandatory for digital ‘gatekeepers’ and eventually integrated into reporting standards for all digital platforms.
Competition, trade, and sustainability in agriculture and food markets in Africa
Authors: Roberts Simon
Published: February 2023

Food and agriculture accounts for around one-third of global emissions reflecting the effects of consumption in high-income countries on production and land use around the world. These effects include those transmitted through international trade such as in the constituents of animal feed for meat. African countries face a dual challenge of adapting to the growing effects of climate change in the shape of extreme weather, and increasing agriculture and food production as part of developing their economies. At the same time, there is increasing concentration in the production and trading of agriculture and food products, globally and within Africa. This article considers the interaction of concentration and responses to climate change in food markets through a focus on meat and animal feed, and the developments in maize and soybeans in East and Southern Africa. The possible role for competition policy as part of a wider reform agenda is proposed.
Cross-border data flows and privacy in global trade law: has trade trumped data protection?
Authors: Burri Mira
Published: February 2023

This article is set against the complex backdrop of the evolution of the data-driven economy and its regulation, and seeks to provide a better contextualization of the topic of data protection as a matter of trade law. It looks at the recent proliferation of rules on data flows, specifically addressed in free trade agreements (FTAs), at how data protection has been framed in these treaties, as well as at the available reconciliation mechanisms developed to interface trade and privacy. The article explores the most advanced models that have been developed in this regard so far, with a focus on some US-led and EU-led treaties. These analyses build the basis for testing the conjecture as to whether trade law has gone too fast and too deep, encroaching on domestic privacy law developments that unfold at a much slower pace.
Market power of digital platforms
Authors: Franck Jens-Uwe , Peitz Martin
Published: February 2023

Digital platforms have reshaped many product markets and play an increasingly important role in economies around the globe. Some of these platforms have become powerful players and may possess a lot of market power. Economists use a number of indicators to assess market power. In this article we discuss to which extent these indicators are helpful in the context of digital platforms. In particular, we focus on assessing entrenched market power and the role of potential competition to constrain this power. Finally, we discuss some cross-border issues of platform market power.
Building trust in digital trade will require a rethink of trade policy-making
Authors: Aaronson Susan Ariel
Published: February 2023

In 2019, Shinzo Abe, then Prime Minister of Japan, stated that if the world wanted to achieve the benefits of the data-driven economy, members of the World Trade Organization should find a common approach to combining ‘data free flow with trust’. However, he never explained what these rules should look like and how nations might find an internationally accepted approach to such rules. In this paper, I argue that trade policy-makers must pay closer attention to users’ concerns if they truly want to achieve ‘data free flow with trust’. I begin with an examination of what the most recent digital trade/ecommerce agreements say about trust and discuss whether they actually meet user concerns. Next, I turn to three different examples of online problems that users have expressed concerns about, namely internet shutdowns/censorship, disinformation, and ransomware, describing how these may yield both trade distortions and less trust online. I argue that policy-makers should address these issues if they believe trade agreements should build trust in cross-border data flows. Moreover, I argue how policy-makers respond to user concerns is as important as what they include in trade agreements. Finally, I note that trade negotiators will need to rethink how they involve the broad public in digital trade policy-making, while recognizing that trade policy agreements may not be the best place to address these problems.
International pro-competition regulation of digital platforms: healthy experimentation or dangerous fragmentation?
Authors: Fletcher Amelia
Published: February 2023

The increasing dominance of a small number of ‘big tech’ companies, across a range of critical online markets, has led to growing calls for regulation to promote more competition, and to ensure that market power is not exploited unfairly. New regulatory regimes to this end are now under development in a variety of jurisdictions. While the new German and EU regulatory regimes are the most advanced, there are detailed proposals under discussion in the UK, US, and China, while in South Korea new regulations have been introduced in relation to the specific area of app stores. This article discusses several questions arising in this context. What problem is pro-competition digital platform regulation trying to solve? Why regulation and not competition law? What are the design challenges involved in developing such regulation? What are the risks arising from diverging regulatory approaches to these global issues and how much these risks be mitigated? And what role can trade policy play?
Rock, scissors, paper: How RNA structure informs function
Authors: Assmann Sarah M , Chou Hong-Li , Bevilacqua Philip C
Published: February 2023

RNA can fold back on itself to adopt a wide range of structures. These range from relatively simple hairpins to intricate 3D folds and can be accompanied by regulatory interactions with both metabolites and macromolecules. The last 50 yr have witnessed elucidation of an astonishing array of RNA structures including transfer RNAs, ribozymes, riboswitches, the ribosome, the spliceosome, and most recently entire RNA structuromes. These advances in RNA structural biology have deepened insight into fundamental biological processes including gene editing, transcription, translation, and structure-based detection and response to temperature and other environmental signals. These discoveries reveal that RNA can be relatively static, like a rock; that it can have catalytic functions of cutting bonds, like scissors; and that it can adopt myriad functional shapes, like paper. We relate these extraordinary discoveries in the biology of RNA structure to the plant way of life. We trace plant-specific discovery of ribozymes and riboswitches, alternative splicing, organellar ribosomes, thermometers, whole-transcriptome structuromes and pan-structuromes, and conclude that plants have a special set of RNA structures that confer unique types of gene regulation. We finish with a consideration of future directions for the RNA structure–function field.
Signaling by the EPFL-ERECTA family coordinates female germline specification through the BZR1 family in Arabidopsis
Authors: Cai Hanyang , Huang Youmei , Liu Liping , Zhang Man , Chai Mengnan , Xi Xinpeng , Aslam Mohammad , Wang Lulu , Ma Suzhuo , Su Han , Liu Kaichuang , Tian Yaru , Zhu Wenhui , Qi Jingang , Dresselhaus Thomas , Qin Yuan
Published: February 2023

In most flowering plants, the female germline is initiated in the subepidermal L2 layer of ovule primordia forming a single megaspore mother cell (MMC). How signaling from the L1 (epidermal) layer could contribute to the gene regulatory network (GRN) restricting MMC formation to a single cell is unclear. We show that EPIDERMAL PATTERNING FACTOR-like (EPFL) peptide ligands are expressed in the L1 layer, together with their ERECTA family (ERf) receptor kinases, to control female germline specification in Arabidopsis thaliana. EPFL-ERf dependent signaling restricts multiple subepidermal cells from acquiring MMC-like cell identity by activating the expression of the major brassinosteroid (BR) receptor kinase BRASSINOSTEROID INSENSITIVE 1 and the BR-responsive transcription factor BRASSINOZOLE RESISTANT 1 (BZR1). Additionally, BZR1 coordinates female germline specification by directly activating the expression of a nucleolar GTP-binding protein, NUCLEOSTEMIN-LIKE 1 (NSN1), which is expressed in early-stage ovules excluding the MMC. Mutants defective in this GRN form multiple MMCs resulting in a strong reduction of seed set. In conclusion, we uncovered a ligand/receptor-like kinase-mediated signaling pathway acting upstream and coordinating BR signaling via NSN1 to restrict MMC differentiation to a single subepidermal cell.
Recent progress and clinical applications of advanced biomaterials in cosmetic surgery
Authors: Li Hairui , Xu Xiujuan , Wu Lina , Chen Xi , Akhter Haris , Wang Yixi , Song Ping , Liao Xiaoxia , Zhang Zhenyu , Li Zhengyong , Zhou Changchun , Cen Ying , Ai Hua , Zhang Xingdong
Published: February 2023

Materials of different allogeneic or xenogeneic or autologous origins are widely used as soft-tissue fillers or structural scaffolds in the field of cosmetic surgery, while complications including prosthesis infection, donor site deformity and filler embolization have always been difficult problems for plastic surgeons. The application of novel biomaterials may bring in hopeful solutions for these problems. Recently, some advanced biomaterials, such as regenerative biomaterials can effectively promote the repair of defective tissues, which have been proven to have good therapeutic as well as cosmetic effects in cosmetic surgery. Therefore, biomaterials with active compounds have drawn significant attention for the tissue regeneration of reconstructive and esthetic treatment. Some of these applications have achieved better clinical outcomes than traditional biological materials. This review summarized recent progress and clinical applications of advanced biomaterials in cosmetic surgery.