bluuebunny/crossref_metadata_2025_split huggingface dataset:
Universal attractors in language evolution provide evidence for the kinds of efficiency pressures involved
Authors: Seržant Ilja A. , Moroz George 
Published: February 2022

AbstractEfficiency is central to understanding the communicative and cognitive underpinnings of language. However, efficiency management is a complex mechanism in which different efficiency effects—such as articulatory, processing and planning ease, mental accessibility, and informativity, online and offline efficiency effects—conspire to yield the coding of linguistic signs. While we do not yet exactly understand the interactional mechanism of these different effects, we argue that universal attractors are an important component of any dynamic theory of efficiency that would be aimed at predicting efficiency effects across languages. Attractors are defined as universal states around which language evolution revolves. Methodologically, we approach efficiency from a cross-linguistic perspective on the basis of a world-wide sample of 383 languages from 53 families, balancing all six macro-areas (Eurasia, North and South America, Australia, Africa, and Oceania). We explore the grammatical domain of verbal person–number subject indexes. We claim that there is an attractor state in this domain to which languages tend to develop and tend not to leave if they happen to comply with the attractor in their earlier stages of evolution. The attractor is characterized by different lengths for each person and number combination, structured along Zipf’s predictions. Moreover, the attractor strongly prefers non-compositional, cumulative coding of person and number. On the basis of these and other properties of the attractor, we conclude that there are two domains in which efficiency pressures are most powerful: strive towards less processing and articulatory effort. The latter, however, is overridden by constant information flow. Strive towards lower lexicon complexity and memory costs are weaker efficiency pressures for this grammatical category due to its order of frequency.
Protein–water coupling tunes the anharmonicity of amide I modes in the interfacial membrane-bound proteins
Authors: Tan Junjun , Ni Zijian , Ye Shuji 
Published: February 2022

The diagonal anharmonicity of an amide I mode of protein backbones plays a critical role in a protein’s vibrational dynamics and energy transfer. However, this anharmonicity of long-chain peptides and proteins in H2O environment is still lacking. Here, we investigate the anharmonicity of the amide I band of proteins at the lipid membrane/H2O interface using a surface-sensitive pump–probe setup in which a femtosecond infrared pump is followed by a femtosecond broadband sum frequency generation vibrational spectroscopy probe. It is found that the anharmonicity of the amide I mode in ideal α-helical and β-sheet structures at hydrophobic environments is 3–4 cm−1, indicating that the amide I mode in ideal α-helical and β-sheet structures is delocalized over eight peptide bonds. The anharmonicity increases as the bandwidth of the amide I mode increases due to the exposure of peptide bonds to H2O. More H2O exposure amounts lead to a larger anharmonicity. The amide I mode of the peptides with large H2O exposure amounts is localized in one to two peptide bonds. Our finding reveals that the coupling between the amide I mode and the H2O bending mode does not facilitate the delocalization of the amide I mode along the peptide chain, highlighting the impact of H2O on energy transfer and structural dynamics of proteins.
Do not forget the Rydberg orbitals
Authors: Simons Jack 
Published: February 2022

Within any molecule or cluster containing one or more positively charged sites, families of Rydberg orbitals exist. Free electrons can attach directly, and anionic reagents with low electron binding energy can transfer an electron into one of these orbitals to form a neutral Rydberg radical. The possibilities that such a radical could form a covalent bond either to another Rydberg radical or to a radical holding its electron in a conventional valence orbital are considered. This Perspective overviews two roles that Rydberg radicals can play, both of which have important chemical consequences. Attachment of an electron into excited Rydberg orbitals is followed by rapid (∼10−6 s) relaxation into the lowest-energy Rydberg orbital to form the ground state radical. Although the excited Rydberg species are stable with respect to fragmentation, the ground-state species is usually quite fragile and undergoes homolytic bond cleavage (e.g., –R2NH dissociates into –R2N + H or into –RNH + R) by overcoming a very small barrier on its potential energy surface, thus generating reactive radicals (H or R). Here, it is shown that as a result of this fragility, any covalent bonds formed by Rydberg radicals are weak and the molecules they form are susceptible to exothermic fragmentations that involve quite small activation barriers. Another role played by Rydberg species arises when the Coulomb potentials provided by the (one or more) positive site(s) in the molecule stabilize low-energy anti-bonding orbitals (e.g., σ* orbitals of weak σ bonds or low-lying π* orbitals) to the extent that electron attachment into these Coulomb-stabilized orbitals is rendered exothermic. In such cases, the overlap of the Rydberg orbitals on the positive site(s) with the σ* or π* orbitals allows either a free electron or a weakly bound electron to an anionic reagent that is attracted toward the positive site by its Coulomb force to be guided/transferred into the σ* or π* orbital instead. After attaching to such an anti-bonding orbital, bond cleavage occurs again, generating reactive radical species. Because of the large radial extent of Rydberg orbitals, this class of bond cleavage events can occur quite distant from the positively charged group. In this Perspective, several examples of both types of phenomena are given for illustrative purposes.
Affinity maturation for an optimal balance between long-term immune coverage and short-term resource constraints
Authors: Chardès Victor , Vergassola Massimo , Walczak Aleksandra M. , Mora Thierry 
Published: February 2022

SignificanceHumoral immunity relies on the mutation and selection of B cells to better recognize pathogens. This affinity maturation process produces cells with diverse recognition capabilities. Examining optimal immune strategies that maximize the long-term immune coverage at a minimal metabolic cost, we show when the immune system should mount a de novo response rather than rely on existing memory cells. Our theory recapitulates known modes of the B cell response, predicts the empirical form of the distribution of clone sizes, and rationalizes as a trade-off between metabolic and immune costs the antigenic imprinting effects that limit the efficacy of vaccines (original antigenic sin). Our predictions provide a framework to interpret experimental results that could be used to inform vaccination strategies.
Using beat frequency in music to adjust running cadence in recreational runners: A randomized multiple baseline design
Authors: te Brake Mark , Stolwijk Niki , Staal Bart , Van Hooren Bas 
Published: February 2022

ABSTRACTRunning with music has been shown to acutely change cadence. However, it is unclear if the increased cadence remains long‐term when running without music in an in‐field situation. The aim of this 12‐week study was to investigate the effect of a 4‐week music running program on cadence, speed and heartrate during and after the music running program. Seven recreational runners with a cadence of <170 steps per minute were randomly assigned to a baseline and post‐intervention period of different durations. During the intervention phase, the participants ran with a musical beat that was 7.5–10% higher than their mean cadence at the start of the study. Cadence, heartrate and running speed were measured twice a week during a 5‐kilometer run with a watch, and were analyzed using randomization tests and visual data inspection. Two participants dropped‐out due to shortage of time (n = 1) and an acute calf injury (n = 1). Cadence significantly increased during the intervention period (+8.5%), and remained elevated during the post‐intervention period (+7.9% (p = .001)) in comparison with the baseline period. Heartrate and running speed did not significantly change during any period. This study among five participants shows that four weeks of running with a musical beat that is 7.5–10% higher than the preferred cadence may be an effective and feasible intervention to increase running cadence. Importantly, the increased cadence occurred without simultaneous increases in running speed and heartrate, hereby potentially reducing mechanical loading without increasing metabolic load.Highlights
Running with a musical rhythm that is higher than the preferred cadence leads to an increased running cadence, without increasing heartrate and running speed.
This cadence remains elevated for at least three to five weeks after the music intervention period.
All individuals showed a practically relevant increase in cadence during and after the intervention.
Consistent truncations around half-maximal AdS5 vacua of 11-dimensional supergravity
Authors: Malek Emanuel , Vall Camell Valentí 
Published: February 2022

Abstract
We use exceptional field theory to systematically study all possible consistent truncations around any M-theory half-maximal vacua of the warped product form AdS5 × M
3 × S
2 × S
1, with M
3 a three-dimensional manifold. We show that, for any of these vacua, only truncations with at most three vector multiplets are consistent. Furthermore, the possible gaugings are restricted to be either SU(2) × U(1) or ISO(3) × U(1) where, in the first case, the U(1) factor can have different embeddings inside the global symmetry group SO(5, n), where n ⩽ 3 equals the number of vector multiplets. This rules out the possibility of any other gauging arising as a consistent truncation around the aforementioned M-theory vacua. Our analysis shows that of the many flows from half-maximal to quarter-maximal AdS5 vacua constructed in five-dimensional supergravity in Bobev (2018 J. High Energy Phys.
6 86), only those corresponding to an adjoint mass deformation in the dual SCFT can be uplifted to 11-dimensional supergravity. The other flows are five-dimensional artefacts without a higher-dimensional origin. Furthermore, consistent truncations with vector multiplets exist only if the vacuum satisfies certain conditions, which we derive.
Hanging a capacitor plate from a spring: a coupled mechanical–electromagnetic oscillator
Authors: Mungan Carl E , Lipscombe Trevor C 
Published: February 2022

Abstract
A pair of coupled nonlinear differential equations describes the oscillations in the position and charge of one of the disks of a parallel-plate capacitor hanging from a spring, if the capacitor is initially charged and then connected to an inductor. For realistic values of the parameters, the results are well-approximated by Mathieu functions wherein the rapid charge oscillations are simultaneously modulated in amplitude and frequency by the slow position oscillations of the plate.
Design of a lattice dielectric cylinder based on multiwalled carbon nanotube-epoxy composite for microwave absorption in the X-band
Authors: Liu Yutong , Zhou Yuhao , Si Kaixuan , Bie Shaowei , Jiang Jianjun 
Published: February 2022

Abstract
To meet the urgent electromagnetic compatibility (EMC) requirements for the electronic products, microwave absorbers with a lattice of the dielectric cylinder were investigated. The elements of the lattice have a cylindrical shape and are composites of epoxy resin filled with multi-walled carbon nanotubes (MWCNTs-EP). The relative complex permittivity of the MWCNT-EP was obtained from the S-parameters measured by the transmission-reflection method with X-band waveguide. The numerical simulation results show that the reflection coefficient of the uniform lattice of the dielectric cylinder is less than −10 dB in the entire X-band (8 GHz–12 GHz) and the reflection coefficient of the hybrid lattice of the dielectric cylinder (HLDC) is less than −15 dB in the same band. Moreover, the reflection coefficient of HLDC is less than −20 dB at normal incidence in the frequency range of 8.4 GHz–11.3 GHz. Further investigation demonstrates that the proposed HLDC could maintain good absorption performance under different incident angles and polarizations. This study suggests that HLDC with the characteristics of lightweight, excellent absorption performance, good angle, and polarization stability provide a promising prospect in the EMC field.
Study of microsecond X-pinches of refractory and non-refractory metals
Authors: Andola Sanjay Chandra , Jaiswar Ashutosh Chandrajeet , Kaushik Trilok Chand , Joshi Keshaw Datt 
Published: February 2022

Abstract
In this report, we present a comparative study on the properties of x-rays from X-pinches made of two groups of metallic wires. The results were obtained on a small current driver having dI/dt of 0.04–0.11 kA ns−1. The X-pinches made of refractory (Mo and W) and non-refractory (Al and Cu) wires were studied for the current required to pinch and their x-ray parameters such as x-ray yield, timing, jitter, number of bursts, and source size. It has been observed that despite lower linear mass density, the Cu group requires a higher current for plasma to pinch than the W group X-pinches. For a given configuration, a faster current compresses the plasma at a higher current which leads to comparatively higher x-ray yield. Substantial enhancement in the quality of x-rays has also been observed in wires with few micron thick dielectric coating. The results of this work can be useful in the development of a small capacitive X-pinch system suitable for studies related to high energy density physics.
Characterization of phonon thermal transport of Ti3C2T
x
MXene thin film
Authors: Wu Hao , Gu Jiaxin , Li Zhongcheng , Liu Wenxiang , Bao Hua , Lin Huan , Yue Yanan 
Published: February 2022

Abstract
Two-dimensional MXene materials with high electrotonic conductivity, good chemical stability, and unique laminar structure show great potential in the field of electrochemistry. In contrast to the widely concerned electrical properties, studies on the thermal properties of MXene materials are very limited. This paper presents a comprehensive analysis of the thermal properties of Ti3C2T
x
MXene thin film. Thermal diffusivity and thermal conductivity of Ti3C2T
x
films are characterized by the transient electro-thermal technique. The experimental results show a 16% enhancement in thermal conductivity when the temperature is increased from 307 K to 352 K. The phonon transport contributes substantially to thermal conductivity compared with electron transport. Molecular dynamic simulation is employed to further investigate the role of phonon thermal transport of Ti3C2 layer. It is found that the combined effect of specific heat capacity, stacking structure and internal stress states is responsible for the thermal transport performance of Ti3C2T
x
MXene thin film.
Non-Markovian systems out of equilibrium: exact results for two routes of coarse graining
Authors: Jung Gerhard 
Published: February 2022

AbstractGeneralized Langevin equations (GLEs) can be systematically derived via dimensional reduction from high-dimensional microscopic systems. For linear models the derivation can either be based on projection operator techniques such as the Mori–Zwanzig (MZ) formalism or by ‘integrating out’ the bath degrees of freedom. Based on exact analytical results we show that both routes can lead to fundamentally different GLEs and that the origin of these differences is based inherently on the non-equilibrium nature of the microscopic stochastic model. The most important conceptional difference between the two routes is that the MZ result intrinsically fulfills the generalized second fluctuation–dissipation theorem while the integration result can lead to its violation. We supplement our theoretical findings with numerical and simulation results for two popular non-equilibrium systems: time-delayed feedback control and the active Ornstein–Uhlenbeck process.
Probing borophene oxidation at the atomic scale
Authors: Liu Xiaolong , Rahn Matthew S , Ruan Qiyuan , Yakobson Boris I , Hersam Mark C 
Published: February 2022

Abstract
Two-dimensional boron (i.e. borophene) holds promise for a variety of emerging nanoelectronic and quantum technologies. Since borophene is synthesized under ultrahigh vacuum (UHV) conditions, it is critical that the chemical stability and structural integrity of borophene in oxidizing environments are understood for practical borophene-based applications. In this work, we assess the mechanism of borophene oxidation upon controlled exposure to air and molecular oxygen in UHV via scanning tunneling microscopy andspectroscopy, x-ray photoelectron spectroscopy, and density functional theory calculations. While borophene catastrophically degrades almost instantaneously upon exposure to air, borophene undergoes considerably more controlled oxidation when exposed to molecular oxygen in UHV. In particular, UHV molecular oxygen dosing results in single-atom covalent modification of the borophene basal plane in addition to disordered borophene edge oxidation that shows altered electronic characteristics. By comparing these experimental observations with density functional theory calculations, further atomistic insight is gained including pathways for molecular oxygen dissociation, surface diffusion, and chemisorption to borophene. Overall, this study provides an atomic-scale perspective of borophene oxidation that will inform ongoing efforts to passivate and utilize borophene in ambient conditions.
Relating boundary and interior solutions of the cohomological equation for cocycles by isometries of negatively curved spaces. The Lǐsic case*
Authors: Moraga Alexis , Ponce Mario 
Published: February 2022

Abstract
We consider the reducibility problem of cocycles by isometries of Gromov hyperbolic metric spaces in the Lǐsic setting. We show that provided that the boundary cocycle (that acts on a compact space) is reducible in a suitable Hölder class, then the original cocycle by isometries (that acts on an unbounded space) is also reducible.
A systematic review of conversion factors between kerma-area product and effective/organ dose for cardiac interventional fluoroscopy procedures performed in adult and paediatric patients
Authors: Brambilla Marco , D’Alessio Andrea , Kuchcinska Agnieszka , Segota Doris , Sukupova Lucie 
Published: February 2022

Abstract
The aim of this systematic review is to undertake a critical appraisal of the evidence in the published literature concerning the conversion factors between kerma-area product (P
KA) and effective/organ dose (DCED_PKA, DCHT_PKA) for cardiac interventional fluoroscopy procedures performed in adults and paediatric patients and to propose reference conversion factors to help standardize dose calculations. A search strategy utilizing MeSH headings in three databases identified 59 (adult) and 37 (paediatric) papers deemed eligible for the review. Exclusion criteria were adopted to select data only from publications which established DCED_PKA in patients using the ICRP 103 tissue weighting factors. A time restriction from January 2007 was introduced in the search to capture the evolving trends of utilization of fluoroscopy-guided intervention technologies only in recent years. The suggested DCED_PKA and DCHT_PKA were synthesized by calculating the weighted averages of the values reported by the authors with weights corresponding to the study sample size. Eighteen studies for both adult (9) and paediatric (9) patients matching the search terms fulfilled the inclusion criteria. The suggested value for DCED_PKA in adult patients amounts to 0.24 mSv Gy−1cm−2. The suggested values for DCHT_PKA ranged from a minimum of 0.15 mSv Gy−1cm−2 for the female breast to a maximum of 0.97 mSv Gy−1cm−2 for the lungs. The suggested values for DCED_PKA in paediatric patients ranged from 3.45 mSv Gy−1cm−2 for the new-born to 0.49 mSv Gy−1cm−2 in the 15 years age class. The suggested values for DCHT_PKA ranged from a minimum of 0.33 mSv Gy−1cm−2 for bone marrow in the 15 years age class to a maximum of 11.49 mSv Gy−1cm−2 for the heart in the new-born. To conclude, values of DCED_PKA/DCHT_PKA were provided for calculating effective/organ doses in cardiac interventional procedures. They can be useful for standardizing dose calculations, hence for comparison of the radiation detriment from different imaging procedures and in the framework of epidemiologic studies.
Line identification of extreme ultraviolet (EUV) spectra from iron, copper and molybdenum ions in EAST tokamak
Authors: Zhang Wenmin , Zhang Ling , Cheng Yunxin , Morita Shigeru , Wang Zhengxiong , Hu Ailan , Zhang Fengling , Duan Yanmin , Zhou Tianfu , Wang Shouxin , Liu Haiqing 
Published: February 2022

Abstract
Extreme ultraviolet (EUV) spectra emitted from iron and copper ions in a range of 8–500 Å and molybdenum ions in a range of 8–400 Å were measured in Experimental Advanced Superconducting Tokamak (EAST) discharges accompanied with spontaneous sputtering events, by which metallic impurity influxes are suddenly increased in the discharge. Several spectral lines from L-, M-, and N-shell partially ionized ions have been successfully observed with two EUV spectrometers named EUV_Short and EUV_Long working in wavelength ranges of 8–130 Å and 20–500 Å, respectively. The wavelength position is accurately calibrated in-situ based on several well-known spectra of low-Z impurity ions. The line identification is carefully performed based on the National Institute of Standards Technology (NIST) database and previously published experimental data. As a result, it is found that B-, Be-, and Li-like iron and copper spectra Al-, Mg-, and Na-like molybdenum spectra appear in discharges with high central electron temperature (>1.8 keV). The highest ionization stages identified here are Li-like iron and copper and Na-like molybdenum, e.g. Fe XXIV at 192.028 Å (1s22p 2P3/2 → 1s22s 2S1/2), Cu XXVII at 153.513 Å (1s22p 2P3/2 → 1s22s 2S1/2) and Mo XXXII at 127.868 Å (2p63p 2P3/2 → 2p63s 2S1/2). Two unresolved transition arrays of molybdenum ions (Mo-UTAs) appear at wavelength ranges of 15–30 Å and 65–95 Å, and are preliminarily identified as Mo XX-Mo XXXII and Mo XVII-Mo XXXII, respectively. In addition, six spectral lines are newly found by comparing a time evolution of the line intensity from impurity ions in different ionization stages, i.e. Fe XVIII at 17.60 ± 0.02 Å, Cu XXI at 13.15 ± 0.02 Å, Cu XVIII at 260.32 ± 0.07 Å, Cu XVIII at 261.00 ± 0.06 Å, Mo XXVIII at 85.30 ± 0.03 Å and Mo XXIX at 89.59 ± 0.03 Å. The wavelengths of EUV spectra identified in this work are summarized in tables with transitions for each impurity species.