bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determinants of left atrioventricular coupling index as a prognostic marker of cardiovascular events from the multi-ethnic atherosclerosis study (MESA)
Authors: Pezel T , Ambale Venkatesh B , De Vasconcellos H , Kato Y , Post W , Wu C , Heckbert S , Bluemke D , Logeart D , Henry P , Lima J 
Published: February 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

BACKGROUND
Recent studies have emphasized the incremental prognostic value of a novel left atrioventricular coupling index (LACI) and its 10-year annual change (ΔLACI) to predict cardiovascular events. However, no study has investigated the potential determinants of this index.

PURPOSE
To identify the determinants of LACI and ΔLACI, measured by cardiovascular magnetic resonance (CMR), and to better understand the parameters governing this left atrioventricular coupling in the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS
In the MESA, 2,112 study participants, free of cardiovascular disease at baseline, had LACI assessed by CMR imaging at baseline (LACIBaseline, Exam 1, 2000–2002) and 10 years later (Exam 5, 2010–2012). The LACI was defined as the ratio of left atrium to left ventricular (LV) end-diastolic volumes. Multivariable linear regression analyses were performed, adjusting for traditional risk factors and LV structure, to identify independent determinants of LACIBaseline or ΔLACI.

RESULTS
In the 2,112 participants (mean age 58.8 ± 9.1 years and 46.6% male), after adjustment for all covariates, age was independently associated with both LACIBaseline (R2 = 0.10) and ΔLACI (R2 = 0.15, both p &lt; 0.001). Although there was no difference in LACIBaseline between women and men (p = 0.19), ΔLACI was higher in women than in men (1.0 ± 1.1 vs. 0.8 ± 1.0 %/year, p &lt; 0.001). African Americans had the highest LACIBaseline value (18.0 ± 7.7%) while Chinese Americans had the lowest (13.8 ± 6.4%, p &lt; 0.001). Diabetes and a higher body mass index were independently associated with LACIBaseline (coefficients B: 1.75 and 0.24, respectively, both p &lt; 0.001). LACIBaseline was independently associated with LV myocardial fibrosis markers (native T1: R2 = 0.11, p = 0.038; and extra-cellular volume [ECV]: R2 = 0.08, p = 0.035) and NT-proBNP levels (R2 = 0.10, p &lt; 0.001) but was not associated with inflammation biomarkers.

CONCLUSIONS
In a multi-ethnic population, age, sex, ethnicity, diabetes, and a higher body mass index were independent determinants of LACI. LACI was independently associated with LV myocardial fibrosis markers and NT-proBNP levels but not associated with inflammation biomarkers.
ClinicalTrials.gov Identifier: NCT00005487 Abstract Figure. Relationship between LACI and Age Abstract Figure. Relationship between LACI and Gender
Radiological cardiothoracic ratio as a potential predictor of right ventricular enlargement in patients with suspected pulmonary embolism due to COVID-19
Authors: Gac P , Truszkiewicz K , Poreba M , Poreba R 
Published: February 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.
Objective. Cases of pulmonary embolism are observed in the course of COVID-19. Right ventricular enlargement is a negative prognostic factor of pulmonary embolism. The cardiothoracic ratio is a routine parameter in the cardiac assessment in chest radiology.
Purpose. The aim of the study was to determine the usefulness of the radiological cardiothoracic ratio (CTR) as a predictor of right ventricular enlargement in patients with suspected pulmonary embolism during COVID-19.
Material and method. The study group consisted of 61 patients with confirmed COVID-19, suspected of pulmonary embolism based on physical examination and laboratory tests (age: 67.18 ± 12.47 years). Computed tomography angiography (CTA) of pulmonary arteries and chest radiograph in AP projection with cardiothoracic ratio assessment were performed in all patients. Right ventricular enlargement was diagnosed by the ratio of right ventricular to left ventricular (RV/LV) dimensions in pulmonary CTA with 2 cut-off points: ≥0.9 and ≥1.0. Heart’s silhouette enlargement was found when CTR on the chest radiograph in the projection AP &gt;0.55.
Results. The mean values of RV/LV and CTR in the studied group were 0.96 ± 0.23 and 0.57 ± 0.05. Pulmonary embolism was diagnosed in 45.9%. Right ventricular enlargement was documented in 44.3% or 29.5% depending on the adopted criterion RV/LV ≥0.9 or RV/LV ≥1.0. Heart’s silhouette enlargement was found in 60.6%. Patients with confirmed pulmonary embolism (PE+) had significantly higher RV/LV ratio and CTR than patients with excluded pulmonary embolism (PE-) (RV/LV: PE+ 1.08 ± 0.24, PE- 0.82 ± 0.12; CTR: PE+ 0.60 ± 0.05, PE- 0.54 ± 0.04; p &lt; 0.05). The correlation analysis showed a statistically significant positive correlation between RV/LV ratio and CTR (r = 0.59, p &lt; 0.05). Based on the ROC curves, CTR values were determined as the optimal cut-off points for the prediction of right ventricular enlargement (RV/LV ≥0.9 or RV/LV ≥1.0), being 0.54 and 0.55, respectively. The sensitivity, specificity, and accuracy of the CTR criterion &gt;0.54 as a predictor of RV/LV ratio ≥0.9 was 0.412, 0.963, and 0.656, respectively, while the CTR criterion &gt;0.55 as a predictor of RV/LV ratio ≥1.0 was 0.488, 0.833, and 0.590, respectively.
Conclusions. In patients with suspected pulmonary embolism during COVID-19, radiographic cardiothoracic ratio may be a predictor of right ventricular enlargement, especially a negative predictor of right ventricular enlargement in case of lower CTR values.
Feasibility of sonothrombolysis in the ambulance for ST-elevation myocardial infarction
Authors: El Kadi S , Porter TR , Zanstra M , Siegers A , Van Loon RB , Hopman LHGA , Van Rossum AC , Kamp O 
Published: February 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Lantheus Medical Imaging, Inc., North Billerica, MA

Background
Patients with ST-elevation myocardial infarction (STEMI) due to coronary occlusion require immediate restoration of epicardial and microvascular blood flow. A potentially new reperfusion method is the use of ultrasound and microbubbles, also called sonothrombolysis. The oscillation and collapse of intravenously administered microbubbles upon exposure to high mechanical index (MI) ultrasound pulses results in thrombus dissolution and stimulates nitric oxide-mediated increases in tissue perfusion. The aim of this study was to assess feasibility of sonothrombolysis in the ambulance for STEMI patients.

Methods
Patients presenting with chest pain and ST-elevations on initial electrocardiogram were included. Sonothrombolysis was applied in the ambulance during patient transfer to the percutaneous coronary intervention (PCI) center. Feasibility was assessed based on duration of sonothrombolysis treatment and number of high MI pulses applied. Vital parameters, ST-resolution, pre- and post-PCI coronary flow and cardiovascular magnetic resonance images were analyzed. Follow up was performed at six months after STEMI.

Results
Twelve patients were screened, of which three patients were included in the study. Sonothrombolysis duration and number of high MI pulses ranged between 12-17 minutes and 32-60 flashes respectively. No changes in vital parameters were observed during and directly after sonothrombolysis. In one case, sonothrombolysis on top of regular pre-hospital care resulted in reperfusion, in another case the effect was inconclusive, and in the last case no effect was seen on reperfusion or definite infarct size.

Conclusion
Sonothrombolysis in the ambulance for STEMI patients is feasible. Larger clinical trials on efficacy and safety of pre-hospital sonothrombolysis are needed. Abstract Figure. Sonothrombolysis set-up in the ambulance Abstract Figure. Sonothrombolysis case with reperfusion
A multivariate statistical approach in correlating the acoustic properties with petrophysics and mineralogy on sandstones
Authors: Garia Siddharth , Pal Arnab Kumar , Ravi K , Nair Archana M 
Published: February 2022

SUMMARYWe examined the effects of the petrophysical and mineralogical variables on the acoustic properties of Upper Assam sandstones. All parameters were evaluated in the laboratory using recognized standard laboratory methods. Compressional wave velocity was measured in the laboratory using piezoelectric transducers of 54 kHz by using the ultrasonic-through transmission technique. Single parameter correlations among bulk density, porosity, permeability and mineralogy with compressional wave velocity showed that the compressional wave velocity correlated inversely with porosity, permeability and feldspar content and directly with bulk density and quartz content. For instance, a plug with a higher amount of feldspar content showed a corresponding decrease in compressional wave velocity. Similarly, higher quartz content showed a higher compressional wave velocity. Nevertheless, to depict a clear correlation among different parameters, a multiparameter analysis was performed. It was observed that the coefficient of determination improved from 0.596 to 0.899 when compressional wave velocity was modelled in terms of bulk density, porosity, quartz and feldspar content collectively, rather than when compressional wave velocity was modelled as a function of porosity alone. Hence, our study suggests that multiple parameters exhibit a coherent influence on compressional wave velocity. Therefore, a multivariate statistical approach involving petrophysical and mineralogical influences would be more realistic. Furthermore, major mineral fractions of sandstone rock type, that is quartz and feldspar fractions were varied for a range of porosity to determine the variations in compressional wave velocity for different saturation conditions. Capturing the fluctuations in compressional wave velocity within the geological constraints will aid in possible reservoir characterization away from the well-control or beyond the available data range. The integrated approach can result in more accurate and precise rock physics models that may help to infer key reservoir parameters. The developed models can be used in quantitative seismic interpretation for reservoir characterization and to identify prospective reservoirs.
Effect of remdesivir on viral dynamics in COVID-19 hospitalized patients: a modelling analysis of the randomized, controlled, open-label DisCoVeRy trial
Authors: Lingas Guillaume , Néant Nadège , Gaymard Alexandre , Belhadi Drifa , Peytavin Gilles , Hites Maya , Staub Thérèse , Greil Richard , Paiva Jose-Artur , Poissy Julien , Peiffer-Smadja Nathan , Costagliola Dominique , Yazdanpanah Yazdan , Wallet Florent , Gagneux-Brunon Amandine , Mentré France , Ader Florence , Burdet Charles , Guedj Jérémie , Bouscambert-Duchamp Maude 
Published: February 2022

Abstract

Background
The antiviral efficacy of remdesivir in COVID-19 hospitalized patients remains controversial.

Objectives
To estimate the effect of remdesivir in blocking viral replication.

Methods
We analysed nasopharyngeal normalized viral loads from 665 hospitalized patients included in the DisCoVeRy trial (NCT 04315948; EudraCT 2020-000936-23), randomized to either standard of care (SoC) or SoC + remdesivir. We used a mathematical model to reconstruct viral kinetic profiles and estimate the antiviral efficacy of remdesivir in blocking viral replication. Additional analyses were conducted stratified on time of treatment initiation (≤7 or &gt;7 days since symptom onset) or viral load at randomization (&lt; or ≥3.5 log10 copies/104 cells).

Results
In our model, remdesivir reduced viral production by infected cells by 2-fold on average (95% CI: 1.5–3.2-fold). Model-based simulations predict that remdesivir reduced time to viral clearance by 0.7 days compared with SoC, with large inter-individual variabilities (IQR: 0.0–1.3 days). Remdesivir had a larger impact in patients with high viral load at randomization, reducing viral production by 5-fold on average (95% CI: 2.8–25-fold) and the median time to viral clearance by 2.4 days (IQR: 0.9–4.5 days).

Conclusions
Remdesivir halved viral production, leading to a median reduction of 0.7 days in the time to viral clearance compared with SoC. The efficacy was larger in patients with high viral load at randomization.
Complete pathological response of post neoadjuvant chemotherapy in colorectal cancer with liver metastasis: a case report
Authors: Al Jazzar Ragad I , Algarni Mohammed , Al-Maiman Sarah , Alzahrani Nayef 
Published: February 2022

Abstract
Treatment of metastatic colorectal cancer has evolved throughout the years and various methods have been proposed to reach a pathological complete response state. We report a case of a 73-year-old male presented with a sigmoid adenocarcinoma with two synchronous liver metastases. The patient received five cycles of FOLFOX neoadjuvant chemotherapy, 41% reduction of tumor size was noted upon reassessment. Therefore, a low anterior resection of the rectum and synchronous resection of segment 5 and 8 of the liver was done along with right-sided diaphragmatic stripping. A pathological complete response was achieved in both primary and secondary tumors that are considered rare and challenging in metastatic colorectal cancer. Neoadjuvant chemotherapy showed promising findings in advanced colorectal cancer.
Pair loading in compact sources
Authors: Done C , Ghisellini G , Fabian A C 
Published: February 2022

Summary
We investigate the effects of a re-acceleration mechanism in compact sources where electron-positron pair production is important. The pairs increase the number of particles to be accelerated and decrease the mean particle energy if the source luminosity remains constant. The acceleration mechanism is loaded. Models in which this effect is included reproduce the γ-ray break seen in active galactic nuclei. It is mainly due to the reduced particle energy and not to photon-photon absorption. The X-ray spectra are generally flatter than those observed if the electrons are accelerated to a single energy. Pair reradiation no longer steepens the spectrum, since loading enhances the importance of the primary emission spectrum. Spectra in agreement with observations can be obtained if the electrons are re-accelerated with a power-law energy distribution.
Our investigation highlights the accumulation of cooled particles within the source. It is a severe constraint on continuous injection models. The lack of any obvious spectral break attributable to Compton downscattering in the high-energy spectra of active galactic nuclei conflicts with the predictions of most models. Highly compact sources produce large amounts of pairs and so have a high optical depth of cooled electrons. We consider this ‘dead electron’ problem for a wide range of models. Reacceleration of the electrons, which is often invoked as a means of overcoming the problem, is not an adequate solution in most cases.
Possible assignment of the 11.3-μm UIR feature to emission from carbonaceous microparticles with internal hydrogens
Authors: Balm S P , Kroto H W 
Published: February 2022

Summary
The carriers of the UIR bands seen in many galactic and extragalactic objects have previously been assigned to emission from polycyclic aromatic hydrocarbons (PAHs). However, the match between laboratory spectra of typical PAHs with the interstellar features in the structurally sensitive 11-15-μm (909-667-cm-1) region remains unsatisfactory. In particular, it has been difficult to explain, considering that a PAH mixture is undoubtedly involved, why only one strong band is seen at 11.3 μm (885 cm-1) and why this has the same position in all sources. We discuss here the possibility that a hitherto unrecognized class of molecule containing a novel type of hydrogen functional group, the internal hydrogen, may provide important new clues to the origin of the 11.3-μm (885 cm-1) feature. This type of grouping is typified by the molecule kekulene which contains six such internal hydrogens and exhibits bands in its IR absorption spectrum which coincide with the interstellar feature. This structural unit is likely to be common in soot-like microparticles which simulations suggest are present in the cool carbon-rich outflows of red giant stars and hence should contribute to the 11.3-μm (885-cm-1) emission.
The Sérsic-Pastoriza galaxy NGC 1808 - 1 . Radio-continuum, optical and H I observations
Authors: Saikia D J , Unger S W , Pedlar A , Yates G J , Axon D J , Wolstencroft R D , Taylor K , Gyldenkerne K 
Published: February 2022

Summary
We present radio-continuum observations made at high angular resolution with the VIA at 20, 6 and 2 cm of the central region of the Sersic-Pastoriza galaxy NGC 1808. These observations reveal a population of compact radio sources, reminiscent of those found in the archetypal starburst galaxies M82 and NGC 253. The bulk of these compact features are not coincident with the optical hot-spots and are likely to be individual or unresolved groups of SNRs. We have also made H i observations of NGC 1808 with the VLA (very large array). Although this was primarily to search for unusual motions which may enable us to understand the nuclear activity, we also obtained information on the large-scale distribution and dynamics of gas in this system. The neutral hydrogen is largely concentrated in a central bar, with weak emission from the spiral arms. An absorption profile against the radio emission from the nuclear region shows two features straddling the systemic velocity. The velocity field of the galaxy is largely consistent with rotation although there is evidence of significant non-circular motions in the bar. We discuss any possible relationship between these non-circular motions and the starburst/nuclear activity in the central region of NGC 1808.
Non-locality of the turbulent electromotive force
Authors: Bendre Abhijit B , Subramanian Kandaswamy 
Published: February 2022

ABSTRACTThe generation of large-scale magnetic fields ($\overline{\boldsymbol {B}}$) in astrophysical systems is driven by the mean turbulent electromotive force ($\overline{\rm{\boldsymbol {\cal E}} {}}$), the cross-correlation between local fluctuations of velocity and magnetic fields. This can depend non-locally on $\overline{\boldsymbol {B}}$ through a convolution kernel Kij. In a new approach to find Kij, we directly fit the time-series data of $\overline{\rm{\boldsymbol {\cal E}} {}}$ versus $\overline{\boldsymbol {B}}$ from a galactic dynamo simulation using singular value decomposition. We calculate the usual turbulent transport coefficients as moments of Kij, and show the importance of including non-locality over eddy length-scales to fully capture their amplitudes and that higher order corrections to the standard transport coefficients are small in this case.
A pixelated approach to galaxy catalogue incompleteness: improving the dark siren measurement of the Hubble constant
Authors: Gray R , Messenger C , Veitch J 
Published: February 2022

ABSTRACT
The use of gravitational wave standard sirens for cosmological analyses is becoming well known, with particular interest in measuring the Hubble constant, H0, and in shedding light on the current tension between early- and late-time measurements. The current tension is over 4σ and standard sirens will be able to provide a completely independent measurement. Dark sirens (binary black hole or neutron star mergers with no electromagnetic counterparts) can be informative if the missing redshift information is provided through the use of galaxy catalogues to identify potential host galaxies of the merger. However, galaxy catalogue incompleteness affects this analysis, and accurate modelling of it is essential for obtaining an unbiased measurement of H0. Previously most methods have assumed uniform completeness within the sky area of a gravitational wave event. This paper presents an updated methodology in which the completeness of the galaxy catalogue is estimated in a directionally dependent matter, by pixelating the sky and computing the completeness of the galaxy catalogue along each line of sight. The H0 inference for a single event is carried out on a pixel-by-pixel basis, and the pixels are combined for the final result. A reanalysis of the events in the first gravitational wave transient catalogue leads to an improvement on the measured value of H0 of approximately 5 per cent compared to the 68.3 per cent highest density interval of the equivalent LIGO and Virgo result, with H0 = $68.8^{+15.9}_{-7.8}$ km s−1 Mpc−1.
Magnetic fields in the formation of the first stars – II. Results
Authors: Stacy Athena , McKee Christopher F , Lee Aaron T , Klein Richard I , Li Pak Shing 
Published: February 2022

ABSTRACT
Beginning with cosmological initial conditions at z = 100, we simulate the effects of magnetic fields on the formation of Population III stars and compare our results with the predictions of Paper I. We use gadget-2 to follow the evolution of the system while the field is weak. We introduce a new method for treating kinematic fields by tracking the evolution of the deformation tensor. The growth rate in this stage of the simulation is lower than expected for diffuse astrophysical plasmas, which have a very low resistivity (high magnetic Prandtl number); we attribute this to the large numerical resistivity in simulations, corresponding to a magnetic Prandtl number of order unity. When the magnetic field begins to be dynamically significant in the core of the minihalo at z = 27, we map it on to a uniform grid and follow the evolution in an adaptive mesh refinement, MHD simulation in orion2. The non-linear evolution of the field in the orion2 simulation violates flux-freezing and is consistent with the theory proposed by Xu & Lazarian. The fields approach equipartition with kinetic energy at densities ∼1010–1012 cm−3. When the same calculation is carried out in orion2 with no magnetic fields, several protostars form, ranging in mass from ∼1 to 30 M⊙; with magnetic fields, only a single ∼30 M⊙ protostar forms by the end of the simulation. Magnetic fields thus suppress the formation of low-mass Pop III stars, yielding a top-heavy Pop III initial mass function and contributing to the absence of observed Pop III stars.
rave: a non-parametric method for recovering the surface brightness and height profiles of edge-on debris discs
Authors: Han Yinuo , Wyatt Mark C , Matrà Luca 
Published: February 2022

ABSTRACT
Extrasolar analogues of the Solar System’s Kuiper belt offer unique constraints on outer planetary system architecture. Radial features such as the sharpness of disc edges and substructures such as gaps may be indicative of embedded planets within a disc. Vertically, the height of a disc can constrain the mass of embedded bodies. Edge-on debris discs offer a unique opportunity to simultaneously access the radial and vertical distribution of material; however, recovering either distribution in an unbiased way is challenging. In this study, we present a non-parametric method to recover the surface brightness profile (face-on surface brightness as a function of radius) and height profile (scale height as a function of radius) of azimuthally symmetric, edge-on debris discs. The method is primarily designed for observations at thermal emission wavelengths, but is also applicable to scattered light observations under the assumption of isotropic scattering. By removing assumptions on underlying functional forms, this algorithm provides more realistic constraints on disc structures. We also apply this technique to Atacama Large Millimeter/submillimeter Array observations of the AU Mic debris disc and derive a surface brightness profile consistent with estimates from parametric approaches, but with a more realistic range of possible models that is independent of parametrization assumptions. Our results are consistent with a uniform scale height of 0.8 au, but a scale height that increases linearly with radius is also possible.