bluuebunny/crossref_metadata_2025 huggingface dataset:
Moments based entanglement criteria and measures
Authors: Wang Yiding , Zhang Tinggui , Huang Xiaofen , Fei Shao-Ming
Published: April 2024

Quantum entanglement plays a key role in quantum computation and quantum information processing. It is of great significance to find efficient and experimentally friend separability criteria to detect entanglement. In this paper, we firstly propose two easily used entanglement criteria based on matrix moments. The first entanglement criterion only uses the first two realignment moments of a density matrix. The second entanglement criterion is based on the moments related to the partially transposed matrix. By detailed examples we illustrate the effectiveness of these criteria in detecting entanglement. Moreover, we provide an experimentally measurable lower bound of concurrence based on these moments. Finally, we present both bipartite and genuine tripartite entanglement measures based on the moments of the reduced states. By detailed examples, we show that our entanglement measures characterize the quantum entanglement in a more fine ways than the existing measures.
Quadratic hyper-surface kernel-free large margin distribution machine-based regression and its least-square form
Authors: He Hao , Wang Kuaini , Jiang Yuzhu , pei Huimin
Published: April 2024

ε-Support vector regression (ε-SVR) is a powerful machine learning approach that focuses on minimizing the margin, which represents the tolerance range between predicted and actual values. However, recent theoretical studies have highlighted that simply minimizing structural risk does not necessarily result in well margin distribution. Instead, it has been shown that the distribution of margins plays a more crucial role in achieving better generalization performance. Furthermore, the kernel-free technique offers a significant advantage as it effectively reduces the overall running time and simplifies the parameter selection process compared to the kernel trick. Based on existing kernel-free regression methods, we present two efficient and robust approaches named quadratic hyper-surface kernel-free large margin distribution machine-based regression (QLDMR) and quadratic hyper-surface kernel-free least squares large margin distribution machine-based regression (QLSLDMR). The QLDMR optimizes the margin distribution by considering both ε-insensitive loss and quadratic loss function similar to the large-margin distribution machine-based regression (LDMR). QLSLDMR aims to reduce the cost of the computing process of QLDMR, which transforms inequality constraints into an equality constraint inspired by least squares support vector machines (LSSVR). Both models combined the spirit of optimal margin distribution with kernel-free technique and after simplification are convex so that they can be solved by some classical methods. Experimental results demonstrate the superiority of the optimal margin distribution combined with the kernel-free technique in robustness, generalization, and efficiency.
Adaptive fast multiplication of ℋ²-matrices
Authors: Börm Steffen
Published: April 2024

Hierarchical matrices approximate a given matrix by a decomposition into low-rank submatrices that can be handled efficiently in factorized form.

H

2

\mathcal {H}^2

-matrices refine this representation following the ideas of fast multipole methods in order to achieve linear, i.e., optimal complexity for a variety of important algorithms.

The matrix multiplication, a key component of many more advanced numerical algorithms, has been a challenge: the only linear-time algorithms known so far either require the very special structure of HSS-matrices or need to know a suitable basis for all submatrices in advance.

In this article, a new and fairly general algorithm for multiplying

H

2

\mathcal {H}^2

-matrices in linear complexity with adaptively constructed bases is presented. The algorithm consists of two phases: first an intermediate representation with a generalized block structure is constructed, then this representation is re-compressed in order to match the structure prescribed by the application.

The complexity and accuracy are analyzed and numerical experiments indicate that the new algorithm can indeed be significantly faster than previous attempts.
Nikishin’s theorem and factorization through Marcinkiewicz spaces
Authors: Mastyło Mieczysław , Sánchez Pérez Enrique
Published: April 2024

Consider

L
0

L^0

, the

F
F

-space of all equivalence classes of measurable functions on a finite measure space equipped with the topology of convergence in measure. Inspired by Nikishin’s classical result on the factorization of sublinear continuous operators from a Banach space to

L
0

L^0

, we prove a theorem that characterizes those maps from any quasi-metric space into

L
0

L^0

that factor strongly through Marcinkiewicz weighted spaces. We show applications to sublinear operators on a certain class of quasi-Banach spaces with generalized Rademacher type generated by Orlicz sequence spaces.
Cuntz algebra automorphisms: Graphs and stability of permutations
Authors: Brenti Francesco , Conti Roberto , Nenashev Gleb
Published: April 2024

We characterize the permutative automorphisms of the Cuntz algebra

O

n

\mathcal {O}_n

(namely, stable permutations) in terms of two sequences of graphs that we associate to any permutation of a discrete hypercube

[
n

]
t

[n]^t

. As applications we show that in the limit of large

t
t

(resp.

n
n

) almost all permutations are not stable, thus proving Conj. 12.5 of Brenti and Conti [Adv. Math. 381 (2021), p. 60], characterize (and enumerate) stable quadratic

4
4

and

5
5

-cycles, as well as a notable class of stable quadratic

r
r

-cycles, i.e. those admitting a compatible cyclic factorization by stable transpositions. Some of our results use new combinatorial concepts that may be of independent interest.
Colength one deformation rings
Authors: Le Daniel , Le Hung Bao , Morra Stefano , Park Chol , Qian Zicheng
Published: April 2024

Let

K

/

Q

p

K/\mathbb {Q}_p

be a finite unramified extension,
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="rho overbar colon normal upper G normal a normal l left-parenthesis double-struck upper Q overbar Subscript p Baseline slash upper K right-parenthesis right-arrow normal upper G normal upper L Subscript n Baseline left-parenthesis double-struck upper F overbar Subscript p Baseline right-parenthesis">

ρ
¯

:

G
a
l

(

Q

¯

p

/

K
)
→

G
L

n

(

F

¯

p

)

\overline {\rho }:\mathrm {Gal}(\overline {\mathbb {Q}}_p/K)\rightarrow \mathrm {GL}_n(\overline {\mathbb {F}}_p)

a continuous representation, and

τ
\tau

a tame inertial type of dimension

n
n

. We explicitly determine, under mild regularity conditions on

τ
\tau

, the potentially crystalline deformation ring

R

ρ
¯

η
,
τ

R^{\eta ,\tau }_{\overline {\rho }}

in parallel Hodge–Tate weights

η
=
(
n
−
1
,
⋯
,
1
,
0
)

\eta =(n-1,\cdots ,1,0)

and inertial type

τ
\tau

when the shape of

ρ
¯

\overline {\rho }

with respect to

τ
\tau

has colength at most one. This has application to the modularity of a class of shadow weights in the weight part of Serre’s conjecture. Along the way we make unconditional the local-global compatibility results of Park and Qian [Mém. Soc. Math. Fr. (N.S.) 173 (2022), pp. vi+150].
Whole brain morphologic features improve the predictive accuracy of IDH status and VEGF expression levels in gliomas
Authors: Zhang Simin , Chen Di , Sun Huaiqiang , Kemp Graham J , Chen Yinying , Tan Qiaoyue , Yang Yuan , Gong Qiyong , Yue Qiang
Published: April 2024

Glioma is a systemic disease that can induce micro and macro alternations of whole brain. Isocitrate dehydrogenase and vascular endothelial growth factor are proven prognostic markers and antiangiogenic therapy targets in glioma. The aim of this study was to determine the ability of whole brain morphologic features and radiomics to predict isocitrate dehydrogenase status and vascular endothelial growth factor expression levels. This study recruited 80 glioma patients with isocitrate dehydrogenase wildtype and high vascular endothelial growth factor expression levels, and 102 patients with isocitrate dehydrogenase mutation and low vascular endothelial growth factor expression levels. Virtual brain grafting, combined with Freesurfer, was used to compute morphologic features including cortical thickness, LGI, and subcortical volume in glioma patient. Radiomics features were extracted from multiregional tumor. Pycaret was used to construct the machine learning pipeline. Among the radiomics models, the whole tumor model achieved the best performance (accuracy 0.80, Area Under the Curve 0.86), while, after incorporating whole brain morphologic features, the model had a superior predictive performance (accuracy 0.82, Area Under the Curve 0.88). The features contributed most in predicting model including the right caudate volume, left middle temporal cortical thickness, first-order statistics, shape, and gray-level cooccurrence matrix. Pycaret, based on morphologic features, combined with radiomics, yielded highest accuracy in predicting isocitrate dehydrogenase mutation and vascular endothelial growth factor levels, indicating that morphologic abnormalities induced by glioma were associated with tumor biology.
An extended continuum-mechanics standard linear solid rheology for fluid-saturated porous rock
Authors: Deng Wubing , Morozov Igor B , Fu Li-Yun , Cao Danping
Published: April 2024

In a large body of rock-physics research, seismic wave velocity dispersion and attenuation in fluid-saturated porous rock are studied by constructing analytical or numerical models for time- or frequency-dependent dynamic (effective, or viscoelastic) moduli. A key and broadly used model of such kind is the Zener's, or the standard linear solid (SLS). This model is qualitatively successful in explaining many field and laboratory observations and serves as the key element of many generalizations such as the Burgers model for plastic deformations or the generalized SLS explaining band-limited or near-constant seismic attenuation. However, as a physical model of fluid-saturated porous rock, the SLS has several major limitations: disregard of inertial effects, absence of secondary wave modes and lack of key physical parameters such as porosity and Skempton coefficients. Grainy and porous rock is an unconsolidated material in which the effective density is frequency-dependent, and its effects on wave velocities may exceed those of the dynamic modulus. To overcome these limitations of the empirical SLS, we propose a rigorous rheologic model based on classical continuum mechanics and called the extended SLS, or eSLS. This rheology explains the available attenuation and dispersion observations equally well, but it is also close to Biot's model, honours all poroelastic relations, includes inertial effects, and reveals several new physical properties of the material. Detailed comparison of the eSLS and Biot's models gives a physical-mechanism-based classification of wave-induced fluid flow (WIFF) phenomena. In this classification, the so-called ‘global-scale’ flows occur in Biot's type structures within the material, whereas the ‘local-scale’ WIFF occurs in eSLS-type structures. Combining Biot's and eSLS models gives a broad class of rheologies for linear anelastic phenomena within rock with a single type of porosity. The model can be readily generalized to multiple porosities and different types of internal variables, such as describing squirt flows, wetting or thermoelastic effects. Modelling is conducted with relatively little effort, using a single matrix equation similar to a mechanical form of the standard SLS. By combining the eSLS and Biot's models, observations of dynamic-modulus dispersion and attenuation can be inverted for macroscopic mechanical properties of porous materials.
Further reactions of organoboranes
Authors: Thomas Susan E.
Published: April 2024

This chapter looks at the process of isomerization. On heating, alkylboranes isomerize and the boron atom moves to a position where steric interactions are minimized. The chapter argues that heating an alkylborane facilitates the elimination of the boron and alpha hydrogen atom to give a boron-hydrogen bond an alkene. The chapter then moves to explore the carbonylation reactions. Carbonylation reactions of alkylboranes are some of the most widely applicable and synthetically useful reactions of these molecules. The chapter shows how carbonylation transforms alkylboranes into many products including aldehydes, ketones, and tertiary alcohols. The chapter concludes by elaborating on the process of cyanidation. It also studies the reaction of trialkylboranes with dichloromethyl methyl ether, and the reaction of an alkylborane with alpha-halocarbonylcompounds.
Mild obesity does not affect perinatal outcome in gestational carrier cycles
Authors: Clain E , Kaizer L K , Sammel M D , Wang J , Homer M , Uhler M , Hoyos L R , Devine K , Polotsky A J
Published: April 2024

STUDY QUESTION

Does BMI of gestational carriers (GCs) affect perinatal outcomes after embryo transfer?

SUMMARY ANSWER

Overweight and class I obesity in GCs does not affect the rate of good perinatal outcomes.

WHAT IS KNOWN ALREADY

The use of GCs is increasing, but uniform guidance regarding optimal BMI for GCs is lacking. Women with obesity who conceive without fertility treatment or through autologous or donor in vitro fertilization are at higher risk of adverse maternal and fetal outcomes, but data on obesity in GCs are very limited.

STUDY DESIGN, SIZE, DURATION

We performed a retrospective cohort study of 1121 GC cycles from January 2015 to December 2020 at US Fertility, the largest national partnership of fertility practices in the USA.

PARTICIPANTS/MATERIALS, SETTING, AND METHODS

All GC cycles performed at a large network of fertility practices were reviewed. Same-sex partners undergoing co-IVF were excluded. The primary outcome was good perinatal outcome from the first embryo transfer, defined as a singleton live birth at ≥37 weeks of gestation with birth weight between 2500 and 4000 g. Secondary outcome measures included frequencies of live birth, clinical pregnancy, miscarriage, full-term birth, low birth weight, large for gestational age, and cesarean delivery. A generalized linear model (log-binomial) was used for each to compare outcomes across BMI groups using normal BMI (20–24.9 kg/m2) as the reference group. Risk ratios and 95% CIs were estimated for each category group relative to normal BMI.

MAIN RESULTS AND THE ROLE OF CHANCE

We identified 1121 cycles in which GCs underwent first embryo transfer, of which 263 (23.5%) were in GCs with BMI >30. Demographics and reproductive history for GCs did not differ by BMI groups. The age of intended parents, use of frozen eggs, and fresh embryo transfers were higher with increasing BMI group. There were no statistically significant associations between BMI and good perinatal outcomes, live birth, clinical pregnancy, biochemical, spontaneous abortion, or low birth weight. However, among live births, higher BMI was significantly associated with birth by cesarean (P = 0.015) and large for gestational age infants (P = 0.023).

LIMITATIONS, REASONS FOR CAUTION

This was a retrospective study, and there may be unmeasured confounders. The number of patients with BMI <20 or ≥35 was small, limiting the power for these groups. We were not able to assess all maternal and fetal outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

In this study, we did not identify any significant impact of BMI on the chances of having a good perinatal outcome. Prior research studies have been inconsistent and this is the largest study to date.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was received for this work. The authors do not have any conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.
A 17-month longitudinal surface sampling study carried out on public transport vehicles operating in England during the COVID-19 pandemic identified low levels of SARS-CoV-2 RNA contamination
Authors: Aranega-Bou Paz , Pottage Thomas , Fenwick Abigail , D'Costa Wilhemina , Brown Natalie F , Yaxley Nicola , King Marco-Felipe , Parker Simon T , Miller Daniel , López-García Martín , Noakes Catherine J , Moore Ginny , Bennett Allan
Published: April 2024

Aims

To monitor severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA contamination in vehicles operating in England during the pandemic, to better understand transmission risk of SARS-CoV-2 on public transport.

Methods and results

We collected 1314 surface samples between December 2020 and April 2022 on trains and buses managed by five different transport operators. The presence of SARS-CoV-2 RNA was investigated through reverse transcription polymerase chain reaction (RT-PCR). SARS-CoV-2 RNA was found on 197 (15%) of the 1314 surfaces sampled, including seat head rests, handholds, and air extract grilles, but the levels of RNA recovered on those samples (median value of 23.4, interquartile range: 14.3–35.4, N gene copies per extraction) made the presence of infectious virus at the time of sampling extremely unlikely. However, detection rates varied over time with peaks broadly coinciding with times of high community transmission, when it was more likely that people infected with SARS-CoV-2 were travelling on public transport.

Conclusion

During the pandemic, and as in other public spaces, low levels of SARS-CoV-2 RNA were found on surfaces associated with public transport.
What Makes Linguistic Inferences Robust?
Authors: Marty Paul , Romoli Jacopo , Sudo Yasutada , Breheny Richard
Published: April 2024

Sentences involving embedded disjunctions give rise to distributive and free choice inferences. These inferences exhibit certain characteristics of Scalar Implicatures (SIs) and some researchers have proposed to treat them as such. This proposal, however, faces an important challenge: experimental results have shown that the two inferences are more robust, faster to process, and easier to acquire than regular SIs. A common response to this challenge has been to hypothesise that such discrepancies among different types of SIs stem from the type of alternative used to derive them. That is, in contrast to regular SIs, distributive and free choice inferences are computed on the basis of sub-constituent alternatives, which are alternatives that are formed without lexical substitutions. This paper reports on a series of experiments that tested this hypothesis by comparing positive, disjunctive sentences giving rise to the two inference types to variants of these sentences involving either negation and conjunction, or negation and disjunction, for which the implicature approach predicts similar inferences on the basis of the same type of alternatives. The investigation also included deontic and epistemic modality, different positions of negation, and was extended to similar comparisons with simple disjunctions and the related ignorance inferences they give rise to. Our results show that, while the inferences are indeed quite robust in the disjunctive cases, regardless of whether negation is present or not, the inferences that their negative, conjunctive variants give rise to are not. These findings are challenging for the hypothesis that the type of alternatives involved in SI computation is a major factor responsible for differences in robustness. We outline two possible alternative explanations of our data.
Article 101 TFEU: Substantive Appraisal
Authors: Jones Alison , Sufrin Brenda , Dunne Niamh
Published: April 2024

This chapter examines the relationship between Article 101(1) and Article 101(3). It looks at the central question of which agreements, decisions and concerted practices have as their object or effect the prevention, restriction or distortion of competition for the purposes of Article 101(1) and at the issue of which agreements are held to infringe Article 101(1) but meet the critera for exemption from the prohibition set out in Article 101(3). The chapter looks at the way in which the interpretation of ‘object or effect the prevention, restriction or distortion of competition’ has changed since the early days of EEC competition law and at the problems of identifying which agreements are restrictive by object and which restrictive by effect. It examines the recent and controversial case law on this matter and the difficulties which remain including the doctrine of ancillary restraints. It then focuses on the analysis of the effect of agreements which are not restrictive by object, including the concept of appreciability and the de minimis notice. The chapter then considers the matter of which restrictive agreements may neverthess escape the prohibition in Article 101(1) because they meet the criteria in Article 101(3) in that they improve the production or distribution of goods or the promotion of technical or economic progress, how this criterion is distinguished from the agreement not having restrictive effects that bring it within Article 101(1) in the first place, and whether the Article 101(3) criteria can encompass socio-political or public policy matters. The chapter considers the application of the Article 101(3) criteria, the shifting of the burden of proof between Article 101(1) and 101(3), and the existence and importance of block exemptions.
Article 102 TFEU: Introduction and Dominant Position
Authors: Jones Alison , Sufrin Brenda , Dunne Niamh
Published: April 2024

Article 102 TFEU deals with the unilateral conduct of undertakings with substantial market power. It thus prohibits one or more undertakings which hold a dominant position in the internal market or a substantial part of it abusing that position insofar as it may affect inter-Member State trade. This chapter discusses the role of Article 102 and the controversy attending its application, and introduces the elements which must be established before the prohibition applies. The Commission’s review of Article 102 and the publication of its Guidance Paper on enforcement priorities, and the relationship between Article 102 and Article 101, are also considered. The chapter then explores in detail one of the principal limbs of the Article 102 prohibition, namely the concept of an undertaking holding a ‘dominant position’ in a relevant market. The definition of a dominant position in the case law of the Court is discussed, alongside its relation to the concept of substantial market power, including the Commission’s treatment in the Guidance Paper. The chapter then considers how dominance is established, addressing, inter aliai, the definition of the relevant market for the purposes of Article 102; the role of market share in establishing dominance; barriers to entry and other factors indicating dominance; and dominant positions in the digital economy. Article 102
Competition, the State, and Public Undertakings: Article 106 TFEU
Authors: Jones Alison , Sufrin Brenda , Dunne Niamh
Published: April 2024

This chapter examines how competition law applies to the actions of the State when it intervenes in the market through undertakings which it controls or owns or which it places in a privileged position. The discussion includes the principle of Union loyalty in Article 4(3) TEU; Article 106(1); Article 106(2); and the Commission’s supervisory and policing powers in Article 106(3). Article 106(1) is a prohibition addressed to Member States against enacting or maintaining in force any measure in relation to public undertakings or undertakings to which they have granted special or exclusive rights which are contrary to the Treaty rules. The chapter discusses what is meant by ‘public undertakings’ and ‘special or exclusive rights’ and examines in the light of the case law what measures are forbidden by Article 106(1), including those involving the cumulation of rights, the extension of a dominant position from one market to another, and the creation of situations of inequality of opportunity. Article 106(2) gives a limited derogation from Article 106(2) to undertakings entrusted with the operation of services of general economic interest (SGEIs). The chapter discusses the concept of ‘services of general economic interest’ and examines the cases in which the derogation has been applied or not applied, including the application of Article 106(2) to compensation for the provision of SGEIs which constitutes State aid. The chapter also considers Article 106(3) and the question of the direct effect of Article 106(1) and (2).
Horizontal Cooperation Agreements
Authors: Jones Alison , Sufrin Brenda , Dunne Niamh
Published: April 2024

This chapter discusses EU competition policy towards horizontal cooperation agreements. It covers joint ventures; the contents of the 2010 Guidelines; the general approach to horizontal cooperation agreements in the Guidelines; information agreements; research and development agreements, including the block emption, Regulation 1217/2010; production agreements, including the block exemption on specialisation agreements, Regulation 1218/2010 ; purchasing agreements; commercialisation agreements; standardisation agreements; and agreements in particular sectors, such as the joint buying or selling of media rights to sports events.
Vertical Agreements
Authors: Jones Alison , Sufrin Brenda , Dunne Niamh
Published: April 2024

This chapter, which discusses EU competition policy towards vertical agreements, begins by outlining the choices available to a supplier when deciding how best to market and sell its products or services to customers, and the impact that the competition rules may have on a supplier's choice, including the treatment of agency agreements. It then discusses the EU approach to vertical agreements, in the light of the Commission’s Verticals Guidelines of 2010, including exclusive dealing, single branding, franchising andselective distribution agreements, and the review of the 2010 regime. It considers the importance in EU law of parallel trade between Member States and how this has influenced policy towards vertical restraints. It analyses the application of Article 101(1) and Article 101(3) to vertical agreements, including the Verticals block exemption of 2010; sub-contracting agreements; and the possible application of Article 102 to distribution agreements.
Mergers
Authors: Jones Alison , Sufrin Brenda , Dunne Niamh
Published: April 2024

This chapter discusses the regime for controlling mergers which have an ‘EU dimension’ under the European Union Merger Regulation (EUMR). The chapter examines: the purposes of merger control; the history of the EUMR; the scheme of the EUMR and the concept of the ‘one-stop shop’; jurisdiction under the EUMR, including the definition of a ‘concentration’ and what amounts to an ‘EU dimension’; procedure, including Phase I and Phase II proceedings; the substantive appraisal of horizontal, and non-horizontal mergers under the EUMR and the test of significantly impeding effective competition (SIEC); EUMR statistics; appeals; and international issues.
Quasars with flare/eclipse-like variability identified in ZTF
Authors: Zheng Zhiyuan , Shi Yong , Jin Shuowen , Dannerbauer H , Gu Qiusheng , Li Xin , Yu Xiaoling
Published: April 2024

Active galactic nuclei (AGNs) are known to exhibit optical/ultraviolet variability and most of them can be well modelled by the damped random walks. Physical processes that are not related to the accretion disc, such as tidal disruption events (TDEs) or moving foreground dusty clouds, can cause flare-like and eclipse-like features in the optical light curve. Both long-term and high-cadence monitoring are needed to identify such features. By combining the Sloan Digital Sky Survey (SDSS), Panoramic Survey Telescope and Rapid Response System, and the Zwicky Transient Facility (ZTF) survey, we are able to identify a rare sample (11) out of the SDSS quasar catalogue ($\sim\!\! 83\, 000$). These quasars exhibit more or less constant brightness but show rapid optical variation in the epochs of ZTF Public Data Release 2. To investigate the possible origins of these flare/eclipse-like variabilities, we propose the second-epoch spectroscopic observations with the Gran Telescopio CANARIAS. We find that the change in accretion rate plays a significant role in these quasar variabilities. Among them, we identify two changing-look AGN candidates: SDSS J1427+2930 and SDSS J1420+3757. The luminosity change of the former may be caused by the enhanced supermassive black hole’s accretion or the TDE, while the latter is more related to the change in the accretion rate.
The Pristine Inner Galaxy Survey – VIII. Characterizing the orbital properties of the ancient, very metal-poor inner Milky Way
Authors: Ardern-Arentsen Anke , Monari Giacomo , Queiroz Anna B A , Starkenburg Else , Martin Nicolas F , Chiappini Cristina , Aguado David S , Belokurov Vasily , Carlberg Ray , Monty Stephanie , Myeong GyuChul , Schultheis Mathias , Sestito Federico , Venn Kim A , Vitali Sara , Yuan Zhen , Zhang Hanyuan , Buder Sven , Lewis Geraint F , Oliver William H , Wan Zhen , Zucker Daniel B
Published: April 2024

The oldest stars in the Milky Way (born in the first few billion years) are expected to have a high density in the inner few kpc, spatially overlapping with the Galactic bulge. We use spectroscopic data from the Pristine Inner Galaxy Survey (PIGS) to study the dynamical properties of ancient, metal-poor inner Galaxy stars. We compute distances using starhorse, and orbital properties in a barred Galactic potential. With this paper, we release the spectroscopic AAT/PIGS catalogue (13 235 stars). We find that most PIGS stars have orbits typical for a pressure-supported population. The fraction of stars confined to the inner Galaxy decreases with decreasing metallicity, but many very metal-poor stars (VMP; [Fe/H] <−2.0) stay confined ($\sim 60~{{\ \rm per \, cent}}$ stay within 5 kpc). The azimuthal velocity vϕ also decreases between [Fe/H] = −1.0 and −2.0, but is constant for VMP stars (at ∼+40 km s−1). The carbon-enhanced metal-poor (CEMP) stars in PIGS appear to have similar orbital properties compared to normal VMP stars. Our results suggest a possible transition between two spheroidal components – a more metal-rich, more concentrated, faster rotating component, and a more metal-poor, more extended and slower/non-rotating component. We propose that the former may be connected to pre-disc in-situ stars (or those born in large building blocks), whereas the latter may be dominated by contributions from smaller galaxies. This is an exciting era where large metal-poor samples, such as in this work (as well as upcoming surveys, e.g. 4MOST), shed light on the earliest evolution of our Galaxy.
Apparent correlation between extrinsic and intrinsic flux variations in the first gravitationally lensed quasar
Authors: Goicoechea L J , Shalyapin V N , Oscoz A
Published: April 2024

To better understand which sources contribute to optical passband fluxes of Q0957+561, we present and analyse light curves of the doubly imaged gravitationally lensed quasar from its discovery to 2023. After an early microlensing event, the difference light curves (describing delay-corrected flux ratios between the two quasar images) only show prominent microlensing gradients over the last 17 yr. In addition to these long time-scale gradients in the gr bands, we detect short time-scale, extrinsically induced differential variations that are highly correlated with the short time-scale intrinsic variability of the quasar in those bands. Both the accretion disc and the broad emission-line region (BELR) contribute to optical passband fluxes, and we also show that realistic contributions of the BELR account for the observed correlations in the gr bands. We would like to highlight that the BELR sources of optical passband fluxes of Q0957+561 should be taken into account when measuring accretion-disc source sizes from microlensing simulations.
Polarized radio emission of RRAT J1854+0306
Authors: Guo Qi , Kong Minzhi , Wang P F , Yan Y , Zhou D J
Published: April 2024

Polarized radio emission of RRAT J1854+0306 is investigated with single pulses using Five-hundred-meter Aperture Spherical Telescope. Its emission is characterized by nulls, narrow and weak pulses, and occasional wide and intense bursts with a nulling fraction of 53.2 per cent. Its burst emission is typically of one rotation, and occasionally of two or three or even five rotations at the most, but without significant periodicity. The integrated pulse profile has an ‘S’-shaped position angle curve that is superposed with orthogonal modes, from which geometry parameters are obtained. Individual pulses exhibit diverse profile morphology with single, double, or multiple peaks. The intensity and width of these pulses are highly correlated, and bright pulses generally have wide profiles with multiple peaks. These nulling behaviours, profile morphology, and polarization demonstrate that a rotating radio transient has the same physical origins as the normal pulsars.
Caspase-mediated processing of TRBP regulates apoptosis during viral infection
Authors: Shibata Keiko , Moriizumi Harune , Onomoto Koji , Kaneko Yuka , Miyakawa Takuya , Zenno Shuhei , Tanokura Masaru , Yoneyama Mitsutoshi , Takahashi Tomoko , Ui-Tei Kumiko
Published: April 2024

RNA silencing is a post-transcriptional gene-silencing mechanism mediated by microRNAs (miRNAs). However, the regulatory mechanism of RNA silencing during viral infection is unclear. TAR RNA-binding protein (TRBP) is an enhancer of RNA silencing that induces miRNA maturation by interacting with the ribonuclease Dicer. TRBP interacts with a virus sensor protein, laboratory of genetics and physiology 2 (LGP2), in the early stage of viral infection of human cells. Next, it induces apoptosis by inhibiting the maturation of miRNAs, thereby upregulating the expression of apoptosis regulatory genes. In this study, we show that TRBP undergoes a functional conversion in the late stage of viral infection. Viral infection resulted in the activation of caspases that proteolytically processed TRBP into two fragments. The N-terminal fragment did not interact with Dicer but interacted with type I interferon (IFN) signaling modulators, such as protein kinase R (PKR) and LGP2, and induced ER stress. The end results were irreversible apoptosis and suppression of IFN signaling. Our results demonstrate that the processing of TRBP enhances apoptosis, reducing IFN signaling during viral infection.
Voters’ Expectations in Constituency Elections without Local Polls
Authors: Stoetzer Lukas F , Kayser Mark A , Leininger Arndt , Murr Andreas E
Published: April 2024

How do voters form accurate expectations about the strength of political candidates in constituency elections if there are no reliable constituency polls available? We argue that voters can use national election polls and past election results to increase the accuracy of their expectations. A survey experiment during the German federal election of 2021 confirms that the provision of national election polls and past results increases the accuracy of voters’ expectations. The analysis further shows that voters leverage the information to update their beliefs. The results have relevant implications for debates about belief formation in low-information environments.
Following a Child’s Lead and Setting Kids Up for Success: Convergence and Divergence in Parenting Ideologies on the Political Right and Left
Authors: Rees Mallory E , Saguy Abigail C
Published: April 2024

Public discourse has become more polarized, especially when it comes to moral issues. Moral issues related to gender and sexuality—particularly concerning children—are politically fraught. To assess the extent to which ideologies about gender and parenting are polarized, we interviewed eighty-five gender activists from diverse political orientations. Surprisingly, we found some convergence in how activists on the political left and right discussed gender and parenting. Specifically, those on the right endorsed some traditionally progressive ideas, including that girls should be able to play with “boy toys” and to aspire to traditionally male pursuits. Meanwhile, in affirming children’s right to express their gender identity, those on the left treated gender identity as innate, an idea traditionally associated with conservatives, while saying little about sexism. These similarities, notwithstanding, we also found important differences between how these two groups discussed gender socialization. We discuss the implications of these different approaches and how caregivers and other adults can reconcile a commitment to affirming children’s gender identity while also addressing gender inequalities.
Walt Whitman and the Art of Nursing
Authors: Strickler Jeff
Published: April 2024

Walt Whitman is commonly known as a noted American poet of the 19th century, but he also had experience providing nursing care during the American Civil War. He wrote about his experiences and was an early proponent of holistic nursing care. This article reviews the life of Walt Whitman and his legacy related to nursing.
Orbital cellulitis
Authors: Cottrell Damon B. , Morris Kristine
Published: April 2024

Cellulitis is a soft tissue infection that presents with erythema, swelling, and pain. When the site of infection is around the eye, it is an ocular emergency. Recognizing orbital cellulitis and understanding its significance can lead to prompt treatment and prevention of untoward patient outcomes.
The Efficacy of Systemic Transdermal Diclofenac Patch for Postoperative Pain After Lumbar Spinal Surgery
Authors: Uematsu Masato , Tamai Koji , Hyakutake Hiroshi , Suzuki Hisataka , Tachi Hiroyuki , Ishikawa Yoko , Kokabu Terufumi , Yanagibashi Yasushi , Terai Hidetomi , Nakamura Hiroaki , Hyakumachi Takahiko
Published: April 2024

Study Design.

A single-center, prospective, comparative study.

Objective.

This study aimed to investigate the efficacy and safety of the systemic transdermal diclofenac patch (DP) for immediate postoperative analgesia after lumbar spinal surgery.

Summary of Background Data.

Effective wound pain control after spinal surgery has been shown to lead to favorable outcomes. Using multimodal analgesia may decrease opioid use for postoperative pain.

Materials and Methods.

Patients who underwent posterior lumbar spinal surgery between August 2022 and January 2023 were divided into 2 groups: patients who underwent surgery on even months and were treated with DP (DP [+] group) and those who underwent surgery on odd months and were not treated with DP (DP [−] group). The demographic data, morphine milligram equivalent (MME) within 24 hours, duration of hospitalization, number of rescue analgesics used, visual analog scale (VAS) scores of wound pain, deterioration in renal function, and other complications were compared. Subgroup analysis consisted of subgroups categorized based on surgical procedure (nonfusion or fusion surgery).

Results.

In total, 111 and 113 patients were enrolled in the DP (+) and DP (−) groups, respectively. There was no significant difference in the deterioration of renal function in the DP (+) group. Overall comparisons demonstrated a significant difference between the DP (+) and DP (−) groups in the number of rescue analgesics used within 1 hour (P=0.046). In the nonfusion surgery subgroups, the MMEs within 24 hours, the number of rescue analgesics used within 1 and 3 hours, as well as the wound pain VAS at 1 and 3 hours postoperatively were significantly lower in the DP (+) group than in the DP (−) group (P=0.010, 0.015, 0.029, 0.005, and 0.048, respectively).

Conclusion.

Systemic transdermal DP may potentially offer safe and effective postoperative analgesia, especially in less invasive procedures, such as nonfusion lumbar spinal surgery.

Level of Evidence.

Level III.
Cervical Spine Surgery Following COVID-19 Infection
Authors: Chan Justin P. , Hoang Henry , Wu Hao-Hua , Park Don Y. , Lee Yu-Po , Bhatia Nitin , Hashmi Sohaib Z. ,   on behalf of the N3C Consortium
Published: April 2024

Study Design:

Retrospective.

Objective:

We utilized the NIH National COVID Cohort Collaborative (N3C) database to characterize the risk profile of patients undergoing spine surgery during multiple time windows following the COVID-19 infection.

Summary of Background Data:

While the impact of COVID-19 on various organ systems is well documented, there is limited knowledge regarding its effect on perioperative complications following spine surgery or the optimal timing of surgery after an infection.

Methods:

We asked the National COVID Cohort Collaborative for patients who underwent cervical spine surgery. Patients were stratified into those with an initial documented COVID-19 infection within 3 time periods: 0–2 weeks, 2–6 weeks, or 6–12 weeks before surgery.

Results:

A total of 29,449 patients who underwent anterior approach cervical spine surgery and 46,379 patients who underwent posterior approach cervical spine surgery were included. Patients who underwent surgery within 2 weeks of their COVID-19 diagnosis had a significantly increased risk for venous thromboembolic events, sepsis, 30-day mortality, and 1-year mortality, irrespective of the anterior or posterior approach. Among patients undergoing surgery between 2 and 6 weeks after COVID-19 infection, the 30-day mortality risk remained elevated in patients undergoing a posterior approach only. Patients undergoing surgery between 6 and 12 weeks from the date of the COVID-19 infection did not show significantly elevated rates of any complications analyzed.

Conclusions:

Patients undergoing either anterior or posterior cervical spine surgery within 2 weeks from the initial COVID-19 diagnosis are at increased risk for perioperative venous thromboembolic events, sepsis, and mortality. Elevated perioperative complication risk does not persist beyond 2 weeks, except for 30-day mortality in posterior approach surgeries. On the basis of these results, it may be warranted to postpone nonurgent spine surgeries for at least 2 weeks following a COVID-19 infection and advise patients of the increased perioperative complication risk when urgent surgery is required.
Comparison of Postoperative Complications and Outcomes in Anterior Cervical Spine Surgery
Authors: Hashimoto Motonori , Hirai Takashi , Sakai Kenichiro , Yamada Kentaro , Sakaeda Kentaro , Hashimoto Jun , Egawa Satoru , Morishita Shingo , Matsukura Yu , Inose Hiroyuki , Kobayashi Yutaka , Onuma Hiroaki , Sakaki Kyohei , Tomori Masaki , Torigoe Ichiro , Ochi Miharu , Ishiguro Hiroki , Tamura Satoshi , Ushio Shuta , Yamada Tsuyoshi , Miyake Norihiko , Kusano Kazuo , Otani Kazuyuki , Shindo Shigeo , Arai Yoshiyasu , Okawa Atsushi , Yoshii Toshitaka
Published: April 2024

Study Design:

Retrospective cohort study.

Objectives:

To compare the frequency of complications and outcomes between patients with ossification of the posterior longitudinal ligament (OPLL) of the cervical spine and those with cervical spondylotic myelopathy (CSM) who underwent anterior surgery.

Summary of Background Data:

Anterior cervical spine surgery for OPLL is an effective surgical procedure; however, it is complex and technically demanding compared with the procedure for CSM. Few reports have compared postoperative complications and clinical outcomes after anterior surgeries between the 2 pathologies.

Methods:

Among 1434 patients who underwent anterior cervical spine surgery at 3 spine centers within the same spine research group from January 2011 to March 2021, 333 patients with OPLL and 488 patients with CSM were retrospectively evaluated. Demographics, postoperative complications, and outcomes were reviewed by analyzing medical records. In-hospital and postdischarge postoperative complications were investigated. Postoperative outcomes were evaluated 1 year after the surgery using the Japanese Orthopaedic Association score.

Results:

Patients with OPLL had more comorbid diabetes mellitus preoperatively than patients with CSM (P<0.001). Anterior cervical corpectomies were more often performed in patients with OPLL than in those with CSM (73.3% and 14.5%). In-hospital complications, such as reoperation, cerebrospinal fluid leak, C5 palsy, graft complications, hoarseness, and upper airway complications, occurred significantly more often in patients with OPLL. Complications after discharge, such as complications of the graft bone/cage and hoarseness, were significantly more common in patients with OPLL. The recovery rate of the Japanese Orthopaedic Association score 1 year postoperatively was similar between patients with OPLL and those with CSM.

Conclusion:

The present study demonstrated that complications, both in-hospital and after discharge following anterior spine surgery, occurred more frequently in patients with OPLL than in those with CSM.
Modified S1 Pedicle Subtraction Osteotomy
Authors: Oyem Precious C. , Greenberg Jacob K. , Rhoads Colin R. , Spiessberger Alexander
Published: April 2024

Study Design:

Surgical technique video.

Objective:

To report a surgical technique to revise patients with previous fusions at L4–S1 leading to an iatrogenic flat back and sagittal imbalance using L5–S1 transforaminal interbody fusion combined with a small S1 corner osteotomy.

Background:

This is a case of a woman (51 y old) with a history of multiple lumbar surgeries, severe back pain, sagittal imbalance, and loss of lordosis.

Methods:

We describe a feasible revision technique in a complex patient with the goal of attaining optimal distribution of lumbar lordosis and sagittal balance through a modified S1 pedicle subtraction osteotomy, and the use of an interbody cage to enhance the fusion rate and facilitate closure of the 3-column osteotomy.

Results:

The preoperative patient lordosis angle of 31 degrees at L1–L4 and 16 degrees at L4–S1 became 12 degrees at L1–L4 and 44 degrees at L4–S1 postoperatively.

Conclusion:

The combination of L5–S1 transforaminal interbody fusion and S1 corner osteotomy is a feasible technique for the restoration of lumbar lordosis in patients with previous fusion and consequent loss of lordosis.
Is Routine Use of External Spinal Orthoses Necessary After Operative Stabilization of Cervical Spine Injuries?
Authors: Moody Derek , Showery James , Lador Ran , Hernandez Isaac , Prasarn Mark L.
Published: April 2024

Study Design:

Retrospective Review.

Objective:

The purpose of this study is to evaluate the efficacy of postoperative cervical orthoses to prevent fixation failure and loss of reduction after operative treatment of cervical spine fractures.

Summary of Background Data:

While cervical orthoses are most times tolerated in trauma patients, it is not clear that postoperative bracing is effective at reducing the rate of fixation failure or nonunion in this patient population. Cervical collars may delay rehabilitation, increase the risk of dysphagia and aspiration, and can contribute to skin breakdown.

Methods:

All patients who underwent operative stabilization for cervical spine injuries at a single institution between January 2015 and August 2019 were identified through the institutional Research Electronic Data Capture (REDcap) database. Patient data, including cervical spine injury, surgery, post-operative orthosis use, and secondary surgeries for loss of reduction or infection, were recorded for all patients meeting the inclusion criteria. The primary outcome was the loss of reduction or failure of fixation, requiring revision surgery. Statistical analysis was performed using Jamovi (Version 1.1) statistical software.

Results:

In all, 201 patients meeting inclusion and exclusion criteria were identified within the study period. Overall, 133 (66.2%) patients were treated with a cervical orthosis postoperatively and 68 (33.8%) patients were allowed to mobilize as tolerated without a cervical orthosis. Fixation failure and loss of reduction occurred in 4 (1.99%) patients. Of these 4, three patients were treated with a cervical orthosis postoperatively. There was no significant difference in the risk of instrumentation failure between patients in the postoperative orthosis and no orthosis groups (P=0.706).

Conclusion:

The use of cervical orthoses after operative stabilization of cervical spine injuries remains controversial. There was no statistically significant difference in hardware failure or loss of fixation between patients treated in cervical orthoses postoperatively and those who were not.