bluuebunny/crossref_metadata_2025_split huggingface dataset:
True-amplitude versus trace-normalized full waveform inversion
Authors: Wang Zhikai , Singh Satish C , Noble Mark 
Published: November 2019

SUMMARY
Full waveform inversion (FWI) is a powerful method to estimate high-resolution physical parameters of the subsurface by iteratively minimizing the misfit between the observed and synthetic seismic data. Standard FWI algorithms measure seismic misfit between amplitude-preserved seismic data (true-amplitude FWI). However, in order to mitigate the variations in sources and recording systems acquired on complex geological structures and the physics that cannot be modelled using an approximation of the seismic wave equation, the observed and synthetic seismic data are normalized trace-by-trace and then used to perform FWI. Trace-by-trace normalization removes the amplitude effects related to offset variations and only keeps the phase information. Furthermore, trace-by-trace normalization changes the true amplitude difference because of different normalization factors used for the corresponding synthetic and observed traces. In this paper, we study the performance of true-amplitude FWI and trace-normalized-residual-based FWI in the time domain. The misfit function of trace-normalized-residual-based FWI is defined such that the adjoint source used in gradient calculation is the trace-normalized seismic residual. We compare the two inversion schemes with synthetic seismic data simulated on laterally invariant models and the more complex 2-D Marmousi model. In order to simulate realistic scenarios, we perform the elastic FWI ignoring attenuation to noisy seismic data and to the synthetic data modelled using a viscoelastic modelling scheme. Comparisons of seismic data and adjoint sources show that trace-by-trace normalization increases the magnitude of seismic data at far offsets, which are usually more cycle-skipped than those at near offsets. The inverted results on linear-gradient models demonstrate that trace-by-trace normalization increases the non-linearity of FWI, so an initial model with sufficient accuracy is required to guarantee the convergence to the global minimum. The inverted results and the final seismic residuals computed using seismic data without trace-by-trace normalization demonstrate that true-amplitude FWI provides inverted models with higher accuracy than trace-normalized-residual-based FWI, even when the unknown density is updated using density–velocity relationship in inversion or in the presence of noise and complex physics, such as attenuation.
Gannets are not attracted to fishing vessels in Iceland—potential influence of a discard ban and food availability
Authors: Clark Bethany L , Vigfúsdóttir Freydís , Jessopp Mark J , Burgos Julian M , Bodey Thomas W , Votier Stephen C 
Published: November 2019

Abstract
Fisheries produce large amounts of waste, providing food subsidies for scavengers. Discards influence seabird movement, demography and community structure, but little is known about seabird–fishery interactions where discarding is banned. Here, we investigate how northern gannets Morus bassanus respond to fishing vessels in Iceland, where discarding commercial species is illegal, but birds may still access bait, offal, or catch. We GPS-tracked 82 foraging trips for 36 breeding gannets from two colonies (Skrúður and Hellisey) and obtained time-matched vessel locations. We classified bird behaviour using Hidden Markov Models and then tested the effect of vessel distance on behavioural state-switching using multi-state Markov models. Fishing vessels were present during 94% of foraging trips. However, the likelihood of gannets switching from travelling to foraging was unaffected by vessel proximity, regardless of gear type or activity. When encountering vessels, gannets rarely foraged but instead were more likely to continue travelling. When controlling for population size, gannet foraging trips at both colonies were shorter than expected, suggesting favourable conditions. The lack of behavioural responses to vessels among Icelandic gannets is likely driven by the discard ban and availability of pelagic fishes. Our findings have implications for understanding bycatch risk and the consequences of discard reforms.
Reducibility of Schrödinger Equation on the Sphere
Authors: Feola Roberto , Grébert Benoît 
Published: November 2019

AbstractIn this article we prove a reducibility result for the linear Schrödinger equation on the sphere $\mathbb{S}^n$ with quasi-periodic in time perturbation. Our result includes the case of unbounded perturbation that we assume to be of order strictly less than $1/2$ and satisfying some parity condition. As far as we know, this is one of the few reducibility results for an equation in more than one dimension with unbounded perturbations. Letus note that, surprisingly, our result does not require the use of the pseudo-differential calculus although the perturbation is unbounded.
Using elastic nets to estimate frailty burden from routinely collected national aged care data
Authors: Moldovan Max , Khadka Jyoti , Visvanathan Renuka , Wesselingh Steve , Inacio Maria C 
Published: November 2019

Abstract

Objectives
To (1) use an elastic net (EN) algorithm to derive a frailty measure from a national aged care eligibility assessment program; (2) compare the ability of EN-based and a traditional cumulative deficit (CD) based frailty measures to predict mortality and entry into permanent residential care; (3) assess if the predictive ability can be improved by using weighted frailty measures.

Materials and Methods
A Cox proportional hazard model based EN algorithm was applied to the 2003–2013 cohort of 903 996 participants for selecting items to enter an EN based frailty measure. The out-of-sample predictive accuracy was measured by the area under the curve (AUC) from Cox models fitted to 80% training and validated on 20% testing samples.

Results
The EN approach resulted in a 178-item frailty measure including items excluded from the 44-item CD-based measure. The EN based measure was not statistically significantly different from the CD-based approach in terms of predicting mortality (AUC 0.641, 95% CI: 0.637–0.644 vs AUC 0.637, 95% CI: 0.634–0.641) and permanent care entry (AUC 0.626, 95% CI: 0.624–0.629 vs AUC 0.627, 95% CI: 0.625–0.63). However, the weighted EN based measure statistically outperforms the weighted CD measure for predicting mortality (AUC 0.774, 95% CI: 0.771–0.777 vs AUC 0.757, 95% CI: 0.754–0.760) and permanent care entry (AUC 0.676, 95% CI: 0.673–0.678 vs AUC 0.671, 95% CI: 0.668–0.674).

Conclusions
The weighted EN and CD-based measures demonstrated similar prediction performance. The CD-based measure items are relevant to frailty measurement and easier to interpret. We recommend using the weighted and unweighted CD-based frailty measures.
Cusp or core? Revisiting the globular cluster timing problem in Fornax
Authors: Meadows Noah , Navarro Julio F , Santos-Santos Isabel , Benítez-Llambay Alejandro , Frenk Carlos 
Published: November 2019

ABSTRACT
We use N-body simulations to revisit the globular cluster (GC) ‘timing problem’ in the Fornax dwarf spheroidal (dSph). In agreement with earlier work, we find that, due to dynamical friction, GCs sink to the centre of dark matter haloes with a cuspy inner density profile but ‘stall’ at roughly 1/3 of the core radius (rcore) in haloes with constant-density cores. The time-scales to sink or stall depend strongly on the mass of the GC and on the initial orbital radius, but are essentially the same for either cuspy (Navarro–Frenk–White) or cored haloes normalized to have the same total mass within rcore. Arguing against a cusp on the basis that GCs have not sunk to the centre is thus no different from arguing against a core, unless all clusters are today at $\sim(1/3)\,r_{\rm core}$. This would imply a core radius exceeding ∼3 kpc, much larger than seems plausible in any core-formation scenario. (The average projected distance of Fornax GCs is 〈RGC, Fnx〉 ∼ 1 kpc and its effective radius is ∼700 pc.) A simpler explanation is that Fornax GCs have only been modestly affected by dynamical friction, as expected if clusters started orbiting at initial radii of the order of ∼1–2 kpc, just outside Fornax’s present-day half-light radius but well within the tidal radius imprinted by Galactic tides. This is not entirely unexpected. Fornax GCs are significantly older and more metal-poor than most Fornax stars, and such populations in dSphs tend to be more spatially extended than their younger and more metal-rich counterparts. Contrary to some earlier claims, our simulations further suggest that GCs do not truly ‘stall’ at $\sim 0.3\, r_{\rm core}$, but rather continue decaying towards the centre, albeit at reduced rates. We conclude that dismissing the presence of a cusp in Fornax based on the spatial distribution of its GC population is unwarranted.
Searching for volcanic activity and a mercury-like exosphere of the super-Earth HD3167 b
Authors: Guenther Eike W , Kislyakova Kristina G 
Published: November 2019

ABSTRACT
HD3167 b is a transiting super-Earth that has a density which is consistent with a rocky composition. The planet is exposed to strong radiation, intense stellar wind, and likely strong tidal forces and induction heating. According to theory, planets that are so close to the star should have an atmosphere like Mercury but much more extended and denser. Other theories predict that such planets have a lava lake on their surfaces and exhibit an enormous volcanic activity. We have calculated the heating by electromagnetic induction to estimate if it can drive significant volcanic activity at HD3167 b and shown that for some magnetic fields the heating can be substantial. HD3167 is an ideal target to search for the exosphere of a planet, and signs of volcanic activity. We observed the planet in- and out-of transit with Ultraviolet and Visual Échelle Spectrograph in order to search for presence of lines originating from the exosphere of the planet such as the $\rm Na\, D_{1,2}$ and Ca ii H&K lines as well as numerous [S II], [S III], and [O III] lines that are tracers of volcanic activity. We derived upper limits for the ratios of the line fluxes to the stellar flux. The upper limits that we derived are $I_{p,\lambda }/I_{*,\lambda }=1.5\, 10^{-3}$ for the Ca ii H&K lines, and $I_{p,\lambda }/I_{*,\lambda }=7.2\, 10^{-4}$ and $I_{p,\lambda }/I_{*,\lambda }=3.3\, 10^{-4}$ for the $\rm NaD_{1,2}$ lines, respectively. The fact that our upper limits correspond to previous detections in 55 Cnc e shows that not all super-Earth show these lines all the time and that they might be variable. we took the text from the GAIA, SIMBAD and APPLAUSE web-pages.
Formation of compact systems of super-Earths via dynamical instabilities and giant impacts
Authors: Poon Sanson T S , Nelson Richard P , Jacobson Seth A , Morbidelli Alessandro 
Published: November 2019

ABSTRACT
The NASA’s Kepler mission discovered ∼700 planets in multiplanet systems containing three or more transiting bodies, many of which are super-Earths and mini-Neptunes in compact configurations. Using N-body simulations, we examine the in situ, final stage assembly of multiplanet systems via the collisional accretion of protoplanets. Our initial conditions are constructed using a subset of the Kepler five-planet systems as templates. Two different prescriptions for treating planetary collisions are adopted. The simulations address numerous questions: Do the results depend on the accretion prescription?; do the resulting systems resemble the Kepler systems, and do they reproduce the observed distribution of planetary multiplicities when synthetically observed?; do collisions lead to significant modification of protoplanet compositions, or to stripping of gaseous envelopes?; do the eccentricity distributions agree with those inferred for the Kepler planets? We find that the accretion prescription is unimportant in determining the outcomes. The final planetary systems look broadly similar to the Kepler templates adopted, but the observed distributions of planetary multiplicities or eccentricities are not reproduced, because scattering does not excite the systems sufficiently. In addition, we find that ∼1 per cent of our final systems contain a co-orbital planet pair in horseshoe or tadpole orbits. Post-processing the collision outcomes suggests that they would not significantly change the ice fractions of initially ice-rich protoplanets, but significant stripping of gaseous envelopes appears likely. Hence, it may be difficult to reconcile the observation that many low-mass Kepler planets have H/He envelopes with an in situ formation scenario that involves giant impacts after dispersal of the gas disc.
Impact of 1/f noise on cosmological parameter constraints for SKA intensity mapping
Authors: Chen T , Battye R A , Costa A A , Dickinson C , Harper S E 
Published: November 2019

ABSTRACT
We investigate the impact of 1/f noise on cosmology for an intensity mapping survey with SKA1-MID Band 1 and Band 2. We use a Fisher matrix approach to forecast constraints on cosmological parameters under the influence of 1/f noise, adopting a semi-empirical model from an earlier work, which results from the residual 1/f noise spectrum after applying a component separation algorithm to remove smooth spectral components. Without 1/f noise, the projected constraints are $4{{\ \rm per\ cent}}$ on w0, $1{{\ \rm per\ cent}}$ on h, $2{{\ \rm per\ cent}}$ on bH i using Band 1+Planck, and $3{{\ \rm per\ cent}}$ on w0, $0.5{{\ \rm per\ cent}}$ on h, $2{{\ \rm per\ cent}}$ on bH i using Band 2+Planck. A representative baseline 1/f noise degrades these constraints by a factor of ∼1.5 for Band 1+Planck, and ∼1.2 for Band 2+Planck. On the power spectrum measurement, higher redshift and smaller scales are more affected by 1/f noise, with minimal contamination comes from z ≲ 1 and ℓ ≲ 100. Subject to the specific scan strategy of the adopted 1/f noise model, one prefers a correlation in frequency with minimized spectral slope, a low knee frequency, and a large telescope slew speed in order to reduce its impact.
Epigenetic modification of cytosines fine tunes the stability of i-motif DNA
Authors: Wright Elisé P , Abdelhamid Mahmoud A S , Ehiabor Michelle O , Grigg Melanie C , Irving Kelly , Smith Nicole M , Waller Zoë A E 
Published: November 2019

Abstracti-Motifs are widely used in nanotechnology, play a part in gene regulation and have been detected in human nuclei. As these structures are composed of cytosine, they are potential sites for epigenetic modification. In addition to 5-methyl- and 5-hydroxymethylcytosine modifications, recent evidence has suggested biological roles for 5-formylcytosine and 5-carboxylcytosine. Herein the human telomeric i-motif sequence was used to examine how these four epigenetic modifications alter the thermal and pH stability of i-motifs. Changes in melting temperature and transitional pH depended on both the type of modification and its position within the i-motif forming sequence. The cytosines most sensitive to modification were next to the first and third loops within the structure. Using previously described i-motif forming sequences, we screened the MCF-7 and MCF-10A methylomes to map 5-methylcytosine and found the majority of sequences were differentially methylated in MCF7 (cancerous) and MCF10A (non-cancerous) cell lines. Furthermore, i-motif forming sequences stable at neutral pH were significantly more likely to be epigenetically modified than traditional acidic i-motif forming sequences. This work has implications not only in the epigenetic regulation of DNA, but also allows discreet tunability of i-motif stability for nanotechnological applications.
mRNA regions where 80S ribosomes pause during translation elongation in vivo interact with protein uS19, a component of the decoding site
Authors: Babaylova Elena S , Gopanenko Alexander V , Bulygin Konstantin N , Tupikin Alexey E , Kabilov Marsel R , Malygin Alexey A , Karpova Galina G 
Published: November 2019

Abstract
In eukaryotic ribosomes, the conserved protein uS19, formerly known as S15, extends with its C-terminal tail to the decoding site. The cross-linking of uS19 to the A site codon has been detected using synthetic mRNAs bearing 4-thiouridine (s4U) residues. Here, we showed that the A-site tRNA prevents this cross-linking and that the P site codon does not contact uS19. Next, we focused on determining uS19-mRNA interactions in vivo by applying the photoactivatable-ribonucleoside enhancing cross-linking and immunoprecipitation method to a stable HEK293 cell line producing FLAG-tagged uS19 and grown in a medium containing s4U. We found that when translation was stopped by cycloheximide, uS19 was efficiently cross-linked to mRNA regions with a high frequency of Glu, Lys and, more rarely, Arg codons. The results indicate that the complexes, in which the A site codon is not involved in the formation of the mRNA-tRNA duplex, are present among the cycloheximide-arrested 80S complexes, which implies pausing of elongating ribosomes at the above mRNA regions. Thus, our findings demonstrate that the human ribosomal protein uS19 interacts with mRNAs during translation elongation and highlight the regions of mRNAs where ribosome pausing occurs, bringing new structural and functional insights into eukaryotic translation in vivo.
Risk of hyperkalemia from renin–angiotensin–aldosterone system inhibitors and factors associated with treatment discontinuities in a real-world population
Authors: Wetmore James B , Yan Heng , Horne Laura , Peng Yi , Gilbertson David T 
Published: November 2019

AbstractBackgroundHyperkalemia rates in renin–angiotensin–aldosterone system (RAAS) inhibitor users, and factors associated with treatment interruptions and cessations, have not been explored in a large, population-wide database.MethodsRAAS inhibitor users were identified in the linked UK Clinical Practice Research Datalink-Hospital Episodes Statistics data set, 2009–15. Treatment interruptions (no active prescription followed by reappearance) and cessations were determined. Hyperkalemia (serum K+&gt;5.5 mmol/L) rates were calculated and factors associated with interruptions and cessations modeled using time-varying Cox regression, including hyperkalemia (as a time-dependent variable).ResultsAmong 434 027 RAAS inhibitor users, the hyperkalemia rate was 1.30 (95% confidence interval 1.28–1.32) per 100 patient-years. Of 73.7% of patients who experienced off-treatment periods, 57.6% experienced interruption only, 7.5% cessation only and 8.6% both. Within 1 year of initiating RAAS inhibitor treatment, approximately one-third of the patients experienced interruption or cessation. Hazard ratios for patients with severe hyperkalemia were 1.10 (10.5–1.16) for interruptions and 3.37 (3.25–3.50) for cessation. Compared with no chronic kidney disease (CKD), risk of interruption was 1.20 (1.16–1.25) and 1.57 (1.44–1.72) for Stages 4 and 5, respectively, and of cessation was 2.20 (2.07–2.33) and 2.87 (2.56–3.22). Risk of interruption increased for patients with heart failure or diabetes [1.04 (1.02–1.05); 1.13 (1.12–1.14), respectively] but the risk of cessation decreased [0.85 (0.82–0.87); 0.92 (0.90–0.94)].ConclusionsRisk of RAAS inhibitor interruption and cessation increased as CKD stage progressed. Efforts targeting reasons for interruptions and, especially, cessations, such as hyperkalemia prevention, could decrease off-treatment periods for patients who would otherwise benefit, such as those with CKD, heart failure or diabetes.
Religion in Interesting Times: Contesting Form, Function, and Future
Authors: Beyer Peter 
Published: November 2019

AbstractReligion in our world is not just a contested category, it is also one which does political work, having implications for the distribution of power in society. Classifying social action and symbols as religion or as something else, above all culture or spirituality, has political implications and is used to carry out political struggles. Starting from two concrete contemporary examples drawn from the Canadian context having to do with smudging and the crucifix, the article argues that the historical form that religion has taken functioned in earlier modern centuries as a way of favourably distributing power to religion’s carriers; but that with the progressive development of secular forms of power, religion has progressively been moving towards become a form that is mostly neutral in terms of social power distribution but can also be a source of power loss, these through interrelated processes of privatization, pluralization, and voluntarization. In current circumstances, therefore, in order for what is or was religious form to preserve or regain its erstwhile function for privileged power distribution, one sees attempts in various instances to dissolve religion into other categories and forms; here the prime instances are (national) culture and (instrumental) spirituality. If this process continues and counter-movements do not succeed, then this points to the progressive deinstitutionalisation of religion in the future, its dissolution into collective culture and personal spirituality, while maintaining its religious form in smaller local and transnational organizations and movements.
Effect of Intratracheal Instillation of ZnO Nanoparticles on Acute Lung Inflammation Induced by Lipopolysaccharides in Mice
Authors: Wang Ping , Zhang Lin , Liao Yanxia , Du Juan , Xu Mengying , Zhao Wen , Yin Shuxian , Chen Guilan , Deng Yu , Li Yiran , Xue Xue , Yang Yiming , Hu Guodong , Chen Yinghua 
Published: November 2019

AbstractAlthough studies have shown toxic effects of zinc oxide (ZnO) particles following inhalation, additional effects on injured lungs, which are characterized by dysfunction of the alveolar-capillary barriers, remain uncharacterized. To explore these additional effects, nano-sized ZnO (nZnO) and bulk-sized ZnO were applied to lipopolysaccharide (LPS)-challenged mouse lungs, which were used as a disease model of acute lung inflammation. An elevated Zn2+ concentration was detected in lung tissue after LPS plus nZnO exposure. Exposure to nZnO in LPS-challenged mice resulted in higher total cell number, proportion of neutrophils, and total protein level in bronchoalveolar lavage fluid. Intratracheal instillation of nZnO intensively aggravated LPS-induced lung inflammation that was accompanied by enhanced expression of interleukin-1β, interleukin-6, monocyte chemotactic protein-1α, and granulocyte-macrophage colony stimulating factor. Catalase, glutathione, and total superoxide dismutase levels were significantly decreased, and the malondialdehyde level was obviously increased in the LPS plus nZnO group. 8-Hydroxyguanosine, a marker for DNA damage, was highly concentrated in the lungs from the LPS plus nZnO group. Furthermore, nZnO increased lung apoptosis in an acute lung inflammation model. Taken together, this evidence indicates that nZnO aggravates lung inflammation related to LPS. This enhancement effect may be mediated via oxidative stress, which can lead to DNA damage and apoptosis. This work is important because of the ever-increasing exposure of people to ZnO nanoparticles in industry. The identification of the toxic effects of nZnO and possible mechanisms revealed in this study provide valuable information for future studies.