bluuebunny/crossref_metadata_2025 huggingface dataset:
Composition of coin and alloys in 2 euro coin
Authors: Rovšek Barbara
Published: April 2023

A few years ago, 14 year old students at the Slovenian physics competition were given the experimental task of measuring the composition of two alloys used in 2 euro coins. By performing some simple but as accurate as possible measurements of the density of the coin (and its parts) with simple measuring devices and applying some simple and justified assumptions, a surprisingly good estimate of the composition of the 2 euro coins was obtained. In this paper, we describe the density measurements performed to solve the experimental task and present the basic results of the competition.
Design of a 240 GHz on-chip dual-polarization receiver for SIS mixer arrays
Authors: Wenninger Jakob , Boussaha Faouzi , Chaumont Christine , Tan Boon-Kok , Yassin Ghassan
Published: April 2023

We report the design of a compact dual-polarization on-chip superconductor–insulator–superconductor receiver for array applications. The planar-circuit receiver chip is comprised of the entire radio frequency (RF) signal processing chain with three main circuit components alongside some auxiliary circuits: (1) a polarization splitting 4-probe orthomode transducer (OMT) that couples the RF and local oscillator signal from free space to the chip via a drilled feedhorn; (2) two hybrids that recombine the power of each polarization from the two sets of orthogonal OMT probes; and (3) twin-junction Nb/AlOx/Nb mixers that downconvert the recombined signals to the intermediate frequency. We ensure that the four side walls of each pixel are free from obscuration, using only the top and bottom of the pixel for various connections. Consequently, the design is extendable to a large format array. In this paper, we present the detailed design of the on-chip receiver, including extensive heterodyne simulations and its potential extension into a large format array.
Stability of dust-acoustic solitary waves in magnetized dusty plasmas: effect of polarization force and degenerate electron temperature
Authors: Abdikian A , Sultana S
Published: April 2023

The influence of polarization force, trapped degenerate electrons, and nonthermal ions on the propagation characteristics of dust acoustic solitary waves (DASWs) in a magnetized dusty plasma is investigated. The reductive perturbation approach has been adopted to derive the extended Zakharov-Kuznetsov (eZK) equation and the solitary pulse solution is obtained to investigate the characteristics of DASWs. Pulse stability has also been analysed following the method proposed by Allen and Rowlands. Influence of different relevant plasma parameters on the growth rate of DASWs is studied. It is also found that the relevant plasma parameters have significant impact on the instability criteria of DASWs. This investigation is useful in explaining the nonlinear structures in ultra-dense degenerate plasma media which may exist in astrophysical compact objects (e.g., white dwarfs, neutron stars, etc.) and high density plasma experiments in which plasma degeneracy and relativistic effects play an important role.
An adaptive digital filter for quasi-Gaussian pulse shaping
Authors: Hong Xu , Li Lin , Wu Junlong , Yang Xiaoyan
Published: April 2023

The radiation detector output is often shaped into Gaussian
or quasi-Gaussian shape to improve the measurement performance. An
adaptive digital Step-Gaussian filter is presented for
quasi-Gaussian pulse shaping in this paper. It can be applied for
both exponential decay input and step input. The transfer function
of the filter is established. The amplitude-frequency features of
the new filter are compared with the PZC-(RC)
n
filter and the
CR-(RC)
n
filter. The results indicate that the new filter has
the same amplitude-frequency features as the PZC-(RC)
n
filter
and it possesses more effective filter performance than the
CR-(RC)
n
filter. An X-ray fluorescence measurement system based
on a FAST-SDD detector is set up for experiments. The proposed
filter is verified by the measured pulses that are generated from a
manganese sample. The shape of the filter output shows that the
Step-Gaussian filter can eliminate the undershoot that exists in the
CR-(RC)
n
filter output. The amplitude spectrums with different
shaping times are created to study the shape of the characteristic
peak. The results show that the Step-Gaussian filter can cancel the
low-energy peak tailing of the 5.89 keV peak. The peak shape
parameter, FWTM/FWHM ratio, is also introduced to evaluate the
performance of peak shape improvement. The 5.89 keV peaks of the
spectrums that are generated by using Step-Gaussian filter are
closer to Gaussian distribution than that of the CR-(RC)
n
 
filter.
Effects of surface roughness and counter body variables on the dry sliding wear behavior of AISI 4140 steel based on the elastoplastic flattening model
Authors: Küçük Yılmaz , Erdoğan Azmi , Kurşuncu Bilal , Gök M Sabri
Published: April 2023

This study aimed to determine the effect of surface roughness and counter body material on the wear behavior of AISI 4140 steel based on the elastoplastic flattening model. Most studies in tribology based on the elastoplastic regime focus on modeling the contact between a sphere and a flat surface. However, these models’ main challenge is determining the real contact area. This study claims that the real contact area can be detected with high accuracy through interface software used in optical microscopy. The sample surfaces were roughened and then supposed to dry sliding wear tests using the AISI 52100 and Al2O3 abrasive counter bodies under varying loads and test durations. It was concluded from the calculations that the sample’s surface roughness value significantly affects the contact pair’s plasticity index and, thus, the sample’s wear behavior against the counter body material. Higher plasticity index values indicating the abrasive effect were obtained with the Al2O3 ball, which has a higher hardness and elasticity modulus than the AISI 52100 steel ball. The surface damage of the sample with a high roughness value was less than the other samples. The COF values obtained with the steel ball were detected as lower than that of the alumina ball. Also, it was seen that the surface roughness parameter and plasticity index values calculated were compatible with the wear characteristics of the test samples. As a result, determining the real contact area between the contacting surfaces and its usability in calculating the elastoplastic flattening model parameters were experimentally tested and verified.
Non-volatile electric control of magnetic and topological properties of MnBi2Te4 thin films
*
Authors: Luo Wei , Du Mao-Hua , Reboredo Fernando A , Yoon Mina
Published: April 2023

In this letter, we propose a mechanism to control the magnetic properties of topological quantum material (TQM) by using magnetoelectric coupling: this mechanism uses a heterostructure of TQM with two-dimensional (2D) ferroelectric material, which can dynamically control the magnetic order by changing the polarization of the ferroelectric material and induce possible topological phase transitions. This concept is demonstrated using the example of the bilayer MnBi2Te4 on ferroelectric In2Se3 or In2Te3, where the polarization direction of the 2D ferroelectrics determines the interfacial band alignment and consequently the direction of the charge transfer. This charge transfer, in turn, enhances the stability of the ferromagnetic state of MnBi2Te4 and leads to a possible topological phase transition between the quantum anomalous Hall (QAH) effect and the zero plateau QAH. Our work provides a route to dynamically alter the magnetic ordering of TQMs and could lead to the discovery of new multifunctional topological heterostructures.
Gap and Type problems in Fourier analysis
Authors: Poltoratski A.
Published: April 2023

We survey history and recent progress in the area of Gap and Type problems of Fourier analysis. Among the applications we discuss problems on sampling sets for entire functions of zero exponential type and oscillations of Fourier integrals. We provide new simple examples illustrating gap ant type formulas.
ASHP National Survey of Pharmacy Practice in Hospital Settings: Workforce — 2022
Authors: Pedersen Craig A , Schneider Philip J , Ganio Michael C , Scheckelhoff Douglas J
Published: April 2023

Purpose

Results of the 2022 ASHP National Survey of Pharmacy Practice in Hospital Settings are presented.

Methods

Pharmacy directors at 1,498 general and children’s medical/surgical hospitals in the United States were surveyed using a mixed-mode method of contact by email and mail. Survey completion was online. IQVIA supplied data on hospital characteristics; the survey sample was drawn from IQVIA’s hospital database.

Results

The response rate was 23.7%. Inpatient pharmacists independently prescribe in 27.1% of hospitals. Advanced analytics are used in 8.7% of hospitals. Pharmacists work in ambulatory or primary care clinics in 51.6% of hospitals operating outpatient clinics. Some level of pharmacy service integration is reported in 53.6% of hospitals. More advanced pharmacy technician roles are emerging. For health systems offering hospital at home services, 65.9% of pharmacy departments are involved. Shortages of pharmacists and technicians were reported but are more acute for pharmacy technicians. Aspects of burnout are being measured in 34.0% of hospitals, and 83.7% are attempting to prevent and mitigate burnout. The average number of full-time equivalents per 100 occupied beds is 16.9 for pharmacists and 16.1 for pharmacy technicians.

Conclusion

Health-system pharmacies are experiencing workforce shortages; however, these shortages have had limited impact on budgeted positions. Workforce challenges are influencing the work of pharmacists and pharmacy technicians. Adoption of practice advancement initiatives has continued the positive trend from past years despite workforce issues.
Magnesium in the treatment of alcohol withdrawal syndrome: a multicenter randomized controlled trial
Authors: Airagnes Guillaume , Valter Rémi , Ducoutumany Géraldine , Vansteene Clément , Trabut Jean-Baptiste , Gorwood Philip , Dubertret Caroline , Matta Joane , Charles-Nelson Anais , Limosin Frédéric
Published: April 2023

Objective

Alcohol withdrawal syndrome (AWS) is a frequent and potentially life-threatening condition experienced in alcohol use disorder. Since hypomagnesemia is involved in AWS’s severity, we conducted a multicenter double-blind randomized placebo-controlled trial to examine the efficacy of oral magnesium supplementation as an adjuvant therapy of AWS.

Material and Methods

Inpatients were recruited in six different centers if they had a baseline score higher than eight on the Revised Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar). The experimental treatment was magnesium lactate dehydrate, administrated three times per day providing a total of 426.6 mg per day and up to 15 days. The primary endpoint was the significant between-group difference of the CIWA-Ar total score change from baseline to 3 days later. The treatment group and baseline score were introduced as covariables in an analysis of covariance.

Results

A total of 98 inpatients were included {71.4% of men; mean age of 49.1 years [standard deviation (SD): 10.3]}. In the intention-to-treat population, the mean reduction of the CIWA-Ar score in the experimental group between baseline and 3 days later was 10.1 (SD: 5.2), whereas it was 9.2 (SD: 3.9) in the control group. The absolute difference of the adjusted mean in the experimental group compared with the control group was −0.69 (SD: 0.72), which did not correspond to a significant between-group difference (P = 0.34). Per-protocol analysis and sensitivity analyses also supported this result. Supplementary analyses found no significant difference regarding benzodiazepine consumption, magnesium blood concentration, and satisfaction to care.

Conclusions

The present study does not support the rationale of systematic oral magnesium supplementation in patients with AWS.
Athena: Specialty Certificate Examination case for cutaneous allergy
Authors: Lim Puo Nen , Macdonald Fiona
Published: April 2023

This is an Athena case highlighting a patient with dermatitis affecting the back with sparing of the lumbar area. We discuss common allergens and highlight important distinguishing features among them.
The Quest for International Legal Status: On Finn Seyersted and the Challenges of Theorizing International Organizations Law
Authors: Bordin Fernando Lusa
Published: April 2023

After so many decades since the emergence of international organizations, the question of their international legal status – the terms on which they participate in the international legal system – remains the subject of debate. Among all the scholars that have contributed to this debate, Finn Seyersted stands out for having offered a forward-looking, sophisticated and uncompromising account of what international organizations are under general international law and of what international rights, obligations and capacities they consequently possess. Yet Seyersted is perceived as a left-field scholar with a bee in his bonnet. His work is often name-checked but rarely engaged with properly. This article highlights Seyersted’s invaluable contribution to the theory of international organizations, which has the merit, among others, of having sensed the direction in which international practice was going. It also ponders how Seyersted’s relative lack of success in becoming a more influential scholar can be viewed as a cautionary tale, for there are empirical, conceptual and normative challenges in the quest for international legal status that his work was not able to meet.
The prediction of shale gas reservoir parameters through a multilayer transfer learning network
Authors: Wang Min , Guo XinPing , Tang HongMing , Yu WeiMing , Zhao Peng , Shi XueWen
Published: April 2023

Due to the strong heterogeneity of the reservoir, it is difficult to extend the classical reservoir parameter prediction model to the new work area. Traditional geological methods rely on experience, while machine learning algorithms lack consideration of reservoir heterogeneity. This makes it impossible for these methods to achieve good predictive performance in new work areas. In this paper, we discuss designing a multilayer deep transfer learning network (MDTL). The network enables accurate prediction of reservoir parameters in new areas based on core and logging data from mature areas. For the architectural design, we establish a network structure that realizes data interaction in different work areas. For network parameter optimization, we design a multilayer maximum mean discrepancy loss function. It guides network training to learn feature knowledge about data in different work areas. For logging data processing, we explore a support vector machine method to remove abnormal noise in logging data. We apply MDTL to predict shale gas porosity and total organic carbon content in southern Sichuan. Compared to state-of-the-art reservoir parameter prediction models, MDTL achieves the best performance in new well areas. The network integrates the idea of multilayer transfer learning, reduces the influence of reservoir heterogeneity and effectively ensures the prediction accuracy.
A superconducting gravimeter on the island of Heligoland for the high-accuracy determination of regional ocean tide loading signals of the North Sea
Authors: Voigt Christian , Sulzbach Roman , Timmen Ludger , Dobslaw Henryk , Weise Adelheid , Deng Zhiguo , Stolarczuk Nico , Pflug Hartmut , Peters Heino , Fietz Michael , Thomas Maik , Förste Christoph , Flechtner Frank
Published: April 2023

The superconducting gravimeter GWR iGrav 047 has been installed on the small offshore island of Heligoland in the North Sea approximately at sea level with the overall aim of high-accuracy determination of regional tidal and non-tidal ocean loading signals. For validation, a second gravimeter (gPhoneX 152) has been setup within a gravity gradiometer approach to observe temporal gravity variations in parallel on the upper land of Heligoland. This study covers the determination of regional ocean tide loading (OTL) parameters based on the two continuous gravimetric time-series after elimination of the height-dependent gravity component by empirical transfer functions between the local sea level from a nearby tide gauge and local attraction effects. After reduction of all gravity recordings to sea level, both gravimeters provide very similar height-independent OTL parameters for the eight major diurnal and semidiurnal waves with estimated amplitudes between 0.3 nm s−2 (Q1) and 11 nm s−2 (M2) and RMSE of 0.1–0.2 nm s−2 for 2 yr of iGrav 047 observations and a factor of 2 worse for 1.5 yr of gPhoneX 152 observations. The mean absolute OTL amplitude differences are 0.3 nm s−2 between iGrav 047 and gPhoneX 152, 0.4 nm s−2 between iGrav 047 and the ocean tide model FES2014b and 0.7 nm s−2 between gPhoneX 152 and FES2014b which is in good agreement with the uncertainty estimations. As by-product of this study, OTL vertical displacements are estimated from the height-independent OTL gravity results from iGrav 047 applying proportionality factors ${\rm d}h/{\rm d}g$ for the eight major waves. These height-to-gravity ratios and the corresponding phase shifts are derived from FES2014b. The OTL vertical displacements from iGrav 047 are estimated with amplitudes between 0.4 mm (Q1) and 5.1 mm (M2) and RMSE of 0.1–0.7 mm. These OTL amplitudes agree with FES2014b within 0.0 (M2) and 0.8 mm (K1) with a mean difference of 0.3 mm only. The OTL amplitudes from almost 5 yr of GNSS observations show deviations of up to 6 mm (M2) compared to vertical displacements from both iGrav 047 and FES2014b, which suggests systematic effects included in the estimation of OTL vertical displacements from GNSS. With the demonstrated accuracy, height-independent sensitivity in terms of gravity and vertical displacements along with the high temporal resolution and the even better performance with length of time-series, iGrav 047 delivers the best observational signal for OTL which is representative for a large part of the North Sea.
Salt reconstruction in full-waveform inversion using topology optimization techniques
Authors: Gonçalves J F , Silva E C N
Published: April 2023

With the increasing advances in the oil and gas industry, seismic imaging near or under salt structures has become an important point in deep-water exploration. Detailed velocity models of these areas are particularly interesting not only to characterize hydrocarbon reservoirs but also to identify potential sites for hydrogen and carbon dioxide storage in offshore salt caverns. Thus, we study the full-waveform inversion for the salt reconstruction in acoustic media with constant density considering the time-harmonic wave propagation in a finite element formulation using the topology optimization (TO) method. This problem is challenging due to the strong velocity contrast between salt bodies and the sedimentary background, in addition to the lack of low-frequency data and the inherent ill-posedness of the inverse problem. In this context, we incorporate techniques from the TO field, usually used in design applications, to overcome or reduce these known problems. We initially defined the squared slowness as a combination of two fields, one related to the salt shape and the other to the background. An interpolation rule based on the solid isotropic material with penalization method, combined with filtering and projection schemes, is used to find the shape of the salt bodies with increased sharpness interfaces. A Helmholtz-type filter is applied to modify the gradient aimed to regularize the problem and provide a more stable way for the salt shape to evolve during the inversion process. In particular, we demonstrate that the proposed approach may be relevant for reconstructing media with salt bodies when a suitable starting model is unavailable, and sharp interfaces are required. In addition, we present inversion results from synthetic data generated by a variable density model to demonstrate the approach capability when subjected to a reconstruction application.
Noninvasive metabolic profiling of cumulus cells, oocytes, and embryos via fluorescence lifetime imaging microscopy: a mini-review
Authors: Venturas Marta , Yang Xingbo , Sakkas Denny , Needleman Dan
Published: April 2023

A major challenge in ART is to select high-quality oocytes and embryos. The metabolism of oocytes and embryos has long been linked to their viability, suggesting the potential utility of metabolic measurements to aid in selection. Here, we review recent work on noninvasive metabolic imaging of cumulus cells, oocytes, and embryos. We focus our discussion on fluorescence lifetime imaging microscopy (FLIM) of the autofluorescent coenzymes NAD(P)H and flavine adenine dinucleotide (FAD+), which play central roles in many metabolic pathways. FLIM measurements provide quantitative information on NAD(P)H and FAD+ concentrations and engagement with enzymes, leading to a robust means of characterizing the metabolic state of cells. We argue that FLIM is a promising approach to aid in oocyte and embryo selection.
Life expectancy among patients with pulmonary tuberculosis is less than one-third of life expectancy in the background population in Guinea-Bissau—an observational study
Authors: Bohlbro Anders Solitander , Hønge Bo Langhoff , Engell-Sørensen Thomas , Mendes Antonio Matteus , Sifna Armando , Gomes Victor , Rudolf Frauke , Wejse Christian
Published: April 2023

Background

Few studies have assessed life expectancy of patients with tuberculosis (TB) against a comparable background population, particularly in low-income, high-incidence settings. This study aimed to estimate the life expectancy (LE) of patients with TB in the West African country of Guinea-Bissau and compare it with the LE of the background population.

Methods

This study used data from the Bandim TB cohort from 2004–20 as well as census data from the capital of Guinea-Bissau. LE was estimated using a bootstrapped Kaplan-Meier survival analysis for patients with TB and the background population, stratifying by age of entry and various patient subgroups. The analysis was further stratified by diagnosis period and length of schooling (an indicator of socioeconomic status), to assess their influence on LE. A sensitivity analysis was performed assuming death at loss to follow-up.

Results

The analysis included 2278 patients and a background population of 169 760 individuals. Overall median LE among 30-year-old patients with TB was 10.7 years (95% CI: 8.7–12.6), compared with 35.8 (95% CI: 35.1–36.5) in the background population. LE was shorter in HIV-infected patients and those who had unsuccessful treatment outcome; however, even among those who were both uninfected with HIV and experienced successful treatment outcome, LE was 20% shorter than in the background population. Longer schooling appeared to decrease mortality.

Conclusions

TB substantially shortens LE. This effect is present even in patients who are uninfected with HIV and who have successful treatment outcome.
A Worker’s Backpack as an Alternative to PAYG Pension Systems
Authors: Díaz-Saavedra Julián , Marimon Ramon , de Sousa João Brogueira
Published: April 2023

Facing an ageing population and historical trends of low employment rates, pay-as-you-go (PAYG) pension systems, currently in place in several European countries, imply very large economic and welfare costs in the coming decades. In an overlapping generations economy with incomplete insurance markets and frictional labour markets, an employment fund, which can be used while unemployed or retired, can enhance production efficiency and social welfare. With an appropriate design, the sustainable Backpack employment fund (BP) can greatly outperform (measured by average social welfare in the economy) existing PAYG systems and also Pareto dominate a full privatization of the pension system, as well as a standard fully funded defined contribution pension system. We show this in a calibrated model of the Spanish economy, by comparing the effect of its ageing transition under these different pension systems and by showing how a front-loaded transition from the PAYG to the BP system can be Pareto improving, while minimizing the cost of the reform.
Comparison of solar activity proxies: eigenvectors versus averaged sunspot numbers
Authors: Zharkova V V , Vasilieva I , Popova E , Shepherd S J
Published: April 2023

We explore the links between the averaged sunspot numbers (SSN) and a modulus summary curve (MSC) of two largest eigenvectors of the solar background magnetic field (SBMF) derived from principal component analysis. MSC has rather close correspondence with the whole set of SSN revealing close cycle timings, duration, and maxima times for the cycles 12–24, 6, 7, and −4, −3, while for a few cycles in the mid-18th and mid-19th centuries there are discrepancies in the maximum amplitudes, durations, and times of the maxima. Possible reasons of these discrepancies related to uncertainties in the SSN observations in the 18th–19th centuries, in MSC definition and the different solar activity entities they represent: toroidal (SSN) and poloidal (MSC) magnetic fields, are discussed. Wavelet and Fourier spectral analysis of SSN and MSC series reveal within 95 per cent confidence levels the same prominent period of 10.7 yr, whereas SSN series show a period of 101 yr and MSC of 342 yr close to or above 95 per cent red-noise level. The correlation coefficients between SSN and MSC series vary from 0.25 for the whole SSN data set (from 1700), to 0.56 for the data sets from 1860, to 0.67 for the data sets from 1900 when all SSN restorations agree. These SSN and MSC data sets are confirmed to be closely but not identically related representing the solar activity in different entities of solar dynamo. Use of the summary curve and MSC of eigenvectors of SBMF can provide additional information to SSN for better understanding of solar activity.
A declining major merger fraction with redshift in the local Universe from the largest-yet catalogue of major and minor mergers in SDSS
Authors: Nevin R , Blecha L , Comerford J , Simon J , Terrazas B A , Barrows R S , Vázquez-Mata J A
Published: April 2023

It is difficult to accurately identify galaxy mergers and it is an even larger challenge to classify them by their mass ratio or merger stage. In previous work we used a suite of simulated mergers to create a classification technique that uses linear discriminant analysis to identify major and minor mergers. Here, we apply this technique to 1.3 million galaxies from the SDSS DR16 photometric catalogue and present the probability that each galaxy is a major or minor merger, splitting the classifications by merger stages (early, late, post-coalescence). We present publicly available imaging predictor values and all of the above classifications for one of the largest-yet samples of galaxies. We measure the major and minor merger fraction (fmerg) and build a mass-complete sample of galaxies, which we bin as a function of stellar mass and redshift. For the major mergers, we find a positive slope of fmerg with stellar mass and negative slope of fmerg with redshift between stellar masses of 10.5 < M*(log M⊙) < 11.6 and redshifts of 0.03 < z < 0.19. We are able to reproduce an artificial positive slope of the major merger fraction with redshift when we do not bin for mass or craft a complete sample, demonstrating the importance of mass completeness and mass binning. We determine that the positive trend of the major merger fraction with stellar mass is consistent with a hierarchical assembly scenario. The negative trend with redshift requires that an additional assembly mechanism, such as baryonic feedback, dominates in the local Universe.
The ultraviolet habitable zone of exoplanets
Authors: Spinelli R , Borsa F , Ghirlanda G , Ghisellini G , Haardt F
Published: April 2023

The dozens of rocky exoplanets discovered in the circumstellar habitable zone (CHZ) currently represent the most suitable places to host life as we know it outside the Solar system. However, the presumed presence of liquid water on the CHZ planets does not guarantee suitable environments for the emergence of life. According to experimental studies, the building blocks of life are most likely produced photochemically in presence of a minimum ultraviolet (UV) flux. On the other hand, high UV flux can be life-threatening, leading to atmospheric erosion and damaging biomolecules essential to life. These arguments raise questions about the actual habitability of CHZ planets around stars other than Solar-type ones, with different UV to bolometric luminosity ratios. By combining the ‘principle of mediocrity’ and recent experimental studies, we define UV boundary conditions (UV-habitable zone, UHZ) within which life can possibly emerge and evolve. We investigate whether exoplanets discovered in CHZs do indeed experience such conditions. By analysing Swift-UV/Optical Telescope data, we measure the near ultraviolet (NUV) luminosities of 17 stars harbouring 23 planets in their CHZ. We derive an empirical relation between NUV luminosity and stellar effective temperature. We find that 18 of the CHZ exoplanets actually orbit outside the UHZ, i.e. the NUV luminosity of their M-dwarf hosts is decisively too low to trigger abiogenesis – through cyanosulfidic chemistry – on them. Only stars with effective temperature ≳3900 K illuminate their CHZ planets with enough NUV radiation to trigger abiogenesis. Alternatively, colder stars would require a high-energy flaring activity.
Determining electron column density fluctuations in a dominant scattering region using pulsar scintillation
Authors: Reardon Daniel J , Coles William A
Published: April 2023

Density fluctuations in the ionized interstellar medium have a profound effect on radio pulsar observations, through angular scattering, intensity scintillations, and small changes in time delays from dispersion. Here we show that it is possible to recover the variations in dispersive delays that originate from a dominant scattering region using measurements of the dynamic spectrum of intensity scintillations, provided that the pulsar velocity and scattering region location are known. We provide a theoretical framework for the technique, which involves estimating the phase gradient from the dynamic spectra and integrating that gradient to obtain phase variations. It can be used to search for “extreme scattering events” (ESEs) in pulsars for which precision dispersion delay measurements are not otherwise possible, or to separate true dispersion variations from apparent variability caused by frequency-dependent pulse shape changes. We demonstrate that it works in practice by recovering an ESE in PSR J1603−7202, which is known from precision dispersion delay measurements from pulsar timing. For this pulsar, we find that the phase gradients also track the long-term variations in electron column density observed by pulsar timing, indicating that the column density variations and the scattering are dominated by the same thin scattering screen. We identify a sudden increase in the scintillation strength and magnitude of phase gradients over ∼days in 2010, indicating a compact structure. A decrease in the electron density in 2012 was associated with persistent phase gradients and preceded a period of decreased scintillation strength and an absence of scintillation arcs.
Coalescing black hole binaries from globular clusters: mass distributions and comparison to gravitational wave data from GWTC-3
Authors: Antonini Fabio , Gieles Mark , Dosopoulou Fani , Chattopadhyay Debatri
Published: April 2023

We use our cluster population model, cBHBd, to explore the mass distribution of merging black hole binaries formed dynamically in globular clusters. We include in our models the effect of mass growth through hierarchical mergers and compare the resulting distributions to those inferred from the third gravitational wave transient catalogue. We find that none of our models can reproduce the peak at m1 ≃ 10 M⊙ in the primary black hole mass distribution that is inferred from the data. This disfavours a scenario where most of the sources are formed in globular clusters. On the other hand, a globular cluster origin can account for the inferred secondary peak at m1 ≃ 35 M⊙, which requires that the most massive clusters form with half-mass densities $\rho _{\rm h,0}\gtrsim 10^4~{\rm M}_{\odot} \, {\rm pc}^{-3}$. Finally, we find that the lack of a high-mass cut-off in the inferred mass distribution can be explained by the repopulation of an initial mass gap through hierarchical mergers. Matching the inferred merger rate above ≃50 M⊙ requires both initial cluster densities $\rho _{\rm h,0}\gtrsim 10^4~{\rm M}_{\odot} \, {\rm pc}^{-3}$, and that black holes form with nearly zero spin. A hierarchical merger scenario makes specific predictions for the appearance and position of multiple peaks in the black hole mass distribution, which can be tested against future data.
New Ga IV, Ga V, Ge IV, and Ge V line widths for white dwarf spectra analysis: quantum mechanical results
Authors: Elabidi H , Sahal-Bréchot S , Dimitrijević M S , Belhadj W , Hamdi R
Published: April 2023

We provide in this paper new Stark broadening parameters for the four ions Ga IV, Ga V, Ge IV, and Ge V. The calculations have been performed using our quantum mechanical method. To the best of our knowledge, the only available Stark broadening results are those of the Ge IV ion, where the semiclassical perturbation and the modified semi-empirical methods have been used. For the three other ions, no data have been found. In 2020 and for the first time, about five hundred lines of trans-iron elements including gallium (Ga) and germanium (Ge) have been identified in the ultraviolet (UV) spectrum of a DAO-type white dwarf BD-22°3467. Other precedent observations showed the existence of Ga IV–V lines in two white dwarfs (G191-B2B and RE 0503-289), and those of Ge IV and Ge V in the UV spectrum of RE 0503-289. Theoretical evaluations and measurements of atomic and Stark broadening data are a pre-requisite for stellar-atmosphere modelling, which is a tool for the determination of the photospheric Ga and Ge abundance in white dwarfs. Since there is no Stark broadening data for the three ions Ga IV, Ga V, and Ge V, our calculations come to fill this gap, and the obtained results can be used for the abundance determination of elements, the calculation of stellar opacity, the interpretation and modelling of stellar spectra, and the estimation of the relative transfer through stellar plasmas. They will be also implemented into the data base of Stark broadening parameters, STARK-B.
Collision of molecular outflows in the L1448–C system
Authors: Toledano-Juárez Iván , de la Fuente Eduardo , Trinidad Miguel A , Tafoya Daniel , Nigoche-Netro Alberto
Published: April 2023

We present a study of the central zone of the star-forming region L1448 at 217–230 GHz (∼1.3 mm) using Atacama Large Millimeter Array observations. Our study focuses on the detection of proto-stellar molecular outflows and the interaction with the surrounding medium towards sources L1448–C(N) and L1448–C(S). Both sources exhibit continuum emission, with L1448–C(N) being the brightest one. Based on its spectral index and the associated bipolar outflow, the continuum emission is the most likely to be associated with a circumstellar disk. The 12CO(J = 2→1) and SiO(J = 5→4) emissions associated with L1448–C(N) trace a bipolar outflow and a jet oriented along the northwest-southeast direction. The 12CO(J = 2→1) outflow for L1448–C(N) has a wide-open angle and a V-shape morphology. The SiO jet is highly collimated and has an axial extent comparable with the 12CO(J = 2→1) emission. There is not SiO(J = 5→4) emission towards L1448–C(S), but there is 12CO(J = 2→1) emission. The observations revealed that the red-shifted lobes of the 12CO(J = 2→1) outflows of L1448–C(N) and L1448–C(S) are colliding. As a result of this interaction, the L1448-C(S) lobe seems to be truncated. The collision of the molecular outflows is also hinted by the SiO(J = 5→4) emission, where the velocity dispersion increases significantly in the interaction zone. We also investigated whether it could be possible that this collision triggers the formation of new stars in the L1448–C system.
Feature guided training and rotational standardization for the morphological classification of radio galaxies
Authors: Brand Kevin , Grobler Trienko L , Kleynhans Waldo , Vaccari Mattia , Prescott Matthew , Becker Burger
Published: April 2023

State-of-the-art radio observatories produce large amounts of data which can be used to study the properties of radio galaxies. However, with this rapid increase in data volume, it has become unrealistic to manually process all of the incoming data, which in turn led to the development of automated approaches for data processing tasks, such as morphological classification. Deep learning plays a crucial role in this automation process and it has been shown that convolutional neural networks (CNNs) can deliver good performance in the morphological classification of radio galaxies. This paper investigates two adaptations to the application of these CNNs for radio galaxy classification. The first adaptation consists of using principal component analysis (PCA) during pre-processing to align the galaxies’ principal components with the axes of the coordinate system, which will normalize the orientation of the galaxies. This adaptation led to a significant improvement in the classification accuracy of the CNNs and decreased the average time required to train the models. The second adaptation consists of guiding the CNN to look for specific features within the samples in an attempt to utilize domain knowledge to improve the training process. It was found that this adaptation generally leads to a stabler training process and in certain instances reduced overfitting within the network, as well as the number of epochs required for training.
Optical/UV emission in the Tidal Disruption Event ASASSN-14li: implications of disc modelling
Authors: Wen Sixiang , Jonker Peter G , Stone Nicholas C , Van Velzen Sjoert , Zabludoff Ann I
Published: April 2023

We predict late-time optical/UV emission from tidal disruption events (TDEs) from our slim accretion disc model (Wen et al. 2020) and explore the impact of the black hole mass M•, black hole spin a•, and accretion disc size. We use these synthetic spectra to successfully fit the multiband Swift observations of ASASSN-14li at >350 d, setting only the host galaxy extinction and outer disc radius as free parameters and employing the M•, a•, disc inclination, and disc accretion rates derived from fitting 10 epochs of ASASSN-14li’s X-ray spectra with the slim disc. To address the nature of the early-time optical/UV emission, we consider two models: shock dissipation and reprocessing. We find that (1) the predicted late-time optical/UV colour (e.g. u − w2) is insensitive to black hole and disc parameters unless the disc spreads quickly; (2) a starburst galaxy extinction model is required to fit the data, consistent with ASASSN-14li’s post-starburst host; (3) surprisingly, the outer disc radius is ≈2 × the tidal radius and ∼constant at late times, showing that viscous spreading is slow or non-existent; (4) the shock model can be self-consistent if M• ≲ 106.75 M⊙, i.e. on the low end of ASASSN-14li’s M• range (106.5–7.1 M⊙; 1σ CL); larger black hole masses require disruption of an unrealistically massive progenitor star; (5) the gas mass needed for reprocessing, whether by a quasi-static or an outflowing layer, can be <0.5 M⊙, consistent with a (plausible) disruption of a solar-mass star.
Interferon-alpha 1 expression indicates the disease activity and response of patients with ankylosing spondylitis to anti-TNF-α treatment
Authors: Li Haibo , Liu Jingjing , Ji Xueping
Published: April 2023

Objectives

This study aimed to investigate whether interferon-alpha 1 (IFNA1) is predictive of Ankylosing spondylitis (AS) progression and treatment response to Tumour necrosis factor inhibitors (TNFis).

Methods

Data of 50 AS patients receiving TNFi for 24 weeks were retrospectively analysed. AS patients who reached the Assessment of Spondyloarthritis International Society 40 response at the W24 were classified as responders to TNFi treatment; otherwise, they were classified as nonresponders. Human fibroblast–like synoviocytes (HFLS) isolated from AS patients (AS-HFLS) were used for in vitro validation.

Results

When the IFNA1 expression level was used to diagnose AS patients, an area under the curve of 0.895 was yielded (P < .001). Pearson correlation analysis showed negative correlations between IFNA1 expression, C-reactive protein (CRP) level, Bath AS Disease Activity Index scores, AS Disease Activity Score with CRP, and the production of inflammatory cytokines. An increased IFNA1 expression level was found to be associated with a better treatment response to TNFi. IFNA1 overexpression could protect HFLS against inflammatory response in the setting of AS.

Conclusions

Blood IFNA1 deficiency is correlated with inflammatory cytokine production and disease activity and is indicative of unsatisfied response to TNFi treatment in AS patients.
Accurate profiling of full-length Fv in highly homologous antibody libraries using UMI tagged short reads
Authors: Levin Itay , Štrajbl Marek , Fastman Yair , Baran Dror , Twito Shir , Mioduser Jessica , Keren Adi , Fischman Sharon , Zhenin Michael , Nimrod Guy , Levitin Natalie , Mayor May Ben , Gadrich Meital , Ofran Yanay
Published: April 2023

Deep parallel sequencing (NGS) is a viable tool for monitoring scFv and Fab library dynamics in many antibody engineering high-throughput screening efforts. Although very useful, the commonly used Illumina NGS platform cannot handle the entire sequence of scFv or Fab in a single read, usually focusing on specific CDRs or resorting to sequencing VH and VL variable domains separately, thus limiting its utility in comprehensive monitoring of selection dynamics. Here we present a simple and robust method for deep sequencing repertoires of full length scFv, Fab and Fv antibody sequences. This process utilizes standard molecular procedures and unique molecular identifiers (UMI) to pair separately sequenced VH and VL. We show that UMI assisted VH-VL matching allows for a comprehensive and highly accurate mapping of full length Fv clonal dynamics in large highly homologous antibody libraries, as well as identification of rare variants. In addition to its utility in synthetic antibody discovery processes, our method can be instrumental in generating large datasets for machine learning (ML) applications, which in the field of antibody engineering has been hampered by conspicuous paucity of large scale full length Fv data.
Crystal structures and identification of novel Cd2+-specific DNA aptamer
Authors: Liu Hehua , Gao Yanqing , Mathivanan Johnsi , Armour-Garb Zev , Shao Zhiwei , Zhang Yixi , Zhao Xin , Shao Qiyuan , Zhang Weizhen , Yang Jie , Cao Chulei , Li Huili , Sheng Jia , Gan Jianhua
Published: April 2023

Cadmium (Cd) is one of the most toxic heavy metals. Exposure to Cd can impair the functions of the kidney, respiratory system, reproductive system and skeletal system. Cd2+-binding aptamers have been extensively utilized in the development of Cd2+-detecting devices; however, the underlying mechanisms remain elusive. This study reports four Cd2+-bound DNA aptamer structures, representing the only Cd2+-specific aptamer structures available to date. In all the structures, the Cd2+-binding loop (CBL-loop) adopts a compact, double-twisted conformation and the Cd2+ ion is mainly coordinated with the G9, C12 and G16 nucleotides. Moreover, T11 and A15 within the CBL-loop form one regular Watson–Crick pair and stabilize the conformation of G9. The conformation of G16 is stabilized by the G8–C18 pair of the stem. By folding and/or stabilizing the CBL-loop, the other four nucleotides of the CBL-loop also play important roles in Cd2+ binding. Similarly to the native sequence, crystal structures, circular dichroism spectrum and isothermal titration calorimetry analysis confirm that several variants of the aptamer can recognize Cd2+. This study not only reveals the underlying basis for the binding of Cd2+ ions with the aptamer, but also extends the sequence for the construction of novel metal–DNA complex.
Real-World Treatment Patterns Among Patients With Metastatic Castration-Resistant Prostate Cancer: Results From an International Study
Authors: Barata Pedro C , Leith Andrea , Ribbands Amanda , Montgomery Rachel , Last Matthew , Arondekar Bhakti , Ivanova Jasmina , Niyazov Alexander
Published: April 2023

Background

There is limited real-world evidence on how increasing use of treatment intensification in metastatic castration-sensitive prostate cancer (mCSPC) has influenced treatment decisions in metastatic castration-resistant prostate cancer (mCRPC). The study objective was to evaluate the impact of novel hormonal therapy (NHT) and docetaxel use in mCSPC on first-line treatment patterns among patients with mCRPC in 5 European countries and the United States (US).

Methods

Physician-reported data on patients with mCRPC from the Adelphi Prostate Cancer Disease Specific Program were descriptively analyzed.

Results

A total of 215 physicians provided data on 722 patients with mCRPC. Across 5 European countries and the US, 65% and 75% of patients, respectively, received NHT, and 28% and 9% of patients, respectively, received taxane chemotherapy as first-line mCRPC treatment. In Europe, patients who had received NHT in mCSPC (n = 76) mostly received taxane chemotherapy in mCRPC (55%). Patients who had received taxane chemotherapy, or who did not receive taxane chemotherapy or NHT in mCSPC (n = 98 and 434, respectively) mostly received NHT in mCRPC (62% and 73%, respectively). In the US, patients who had received NHT, taxane chemotherapy, or neither in mCSPC (n = 32, 12, and 72, respectively) mostly received NHT in mCRPC (53%, 83%, and 83%, respectively). Two patients in Europe were rechallenged with the same NHT.

Conclusions

These findings suggest that physicians consider mCSPC treatment history when making first-line treatment decisions in mCRPC. Further studies are needed to better understand optimal treatment sequencing, especially as new treatments emerge.