bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vamos en Palma ‘we are going to Palma’
Authors: Enrique-Arias Andrés 
Published: December 2020

Abstract
This study analyzes historical and contemporary data of
Spanish produced by Catalan-dominant bilinguals in Majorca to
explore the origin and historical evolution of a contact feature of
Majorcan Spanish: the preposition en to express
direction of movement. The transgenerational survival of this
feature of Majorcan Spanish for over three centuries points to a
scenario of intra-community recycling of a structure that emerged as
the result of incomplete grammatical competence in Spanish and was
then perpetuated by limited contact with monolingual Spanish
speakers. The changing linguistic ecology of Majorca, however, with
wider access to canonical varieties of Spanish in the last half
century, has facilitated the demise of this trait among younger
urban generations.
Anthroponymic perseverance of Spanish vestigial 〈x〉
Authors: Parada Maryann 
Published: December 2020

Abstract
Until the early 19th century, the letter 〈x〉 was a common representation of the voiceless velar fricative /x/ (Quixote, brúxula). Despite the Royal Spanish Academy’s (RAE) 1815 elimination of 〈x〉 for /x/, it has survived in a number of Mexican indigenous toponyms and their derivatives as well as in a handful of Spanish anthroponymic variants. Drawing on diatopic, diachronic demographic data, this paper traces the retention of vestigial 〈x〉 in six anthroponymic variants: the given name Ximena and the surnames Ximénez/Ximenes, Mexía/s, and Roxas. These forms can be attributed to the often exceptional orthography of proper nouns from a normative perspective. In the case of Ximena, a powerful resurgence of the feature is linked to robust indexicalities of 〈x〉 in Mexican society.
Effects of adding post‐workout microcurrent in males cross country athletes
Authors: Naclerio Fernando , Moreno‐Perez Diego , Seijo Marcos , Karsten Bettina , Larrosa Mar , García‐Merino Jose Ánge L. , Thirkell Jack , Larumbe‐Zabala Eneko 
Published: December 2020

AbstractPost‐exercise microcurrent based treatments have shown to optimise exercise‐induced adaptations in athletes. We compared the effects of endurance training in combination with either, a microcurrent or a sham treatment, on endurance performance. Additionally, changes in body composition, post‐exercise lactate kinetics and perceived delayed onset of muscle soreness (DOMS) were determined. Eighteen males (32.8 ± 6.3 years) completed an 8‐week endurance training programme involving 5 to 6 workouts per week wearing a microcurrent (MIC, n=9) or a sham (SH, n=9) device for 3‐h post‐workout or in the morning during non‐training days. Measurements were conducted at pre‐ and post‐intervention. Compared to baseline, both groups increased (P < 0.01) maximal aerobic speed (MIC, pre = 17.6 ± 1.3 to post=18.3 ± 1.0; SH, pre=17.8 ± 1.5 to post = 18.3 ± 1.3 km.h−1) with no changes in O2peak. No interaction effect per group and time was observed (P=0.193). Although both groups increased (P < 0.05) trunk lean mass (MIC, pre=23.2 ± 2.7 to post=24.2 ± 2.0; SH, pre=23.4 ± 1.7 to post=24.3 ± 1.6 kg) only MIC decreased (pre=4.8 ± 1.5 to post=4.5 ± 1.5, p=0.029) lower body fat. At post‐intervention, no main differences between groups were observed for lactate kinetics over the 5 min recovery period. Only MIC decreased (P<0.05) DOMS at 24‐h and 48‐h, showing a significant average lower DOMS score over 72‐h after the completion of the exercise‐induced muscle soreness protocol. In conclusion, a 3‐h daily application of microcurrent over an 8‐week endurance training programme produced no further benefits on performance in endurance‐trained males. Nonetheless, the post‐workout microcurrent application promoted more desirable changes in body composition and attenuated the perception of DOMS over 72‐h post‐exercise.
Horizon hair from inversion symmetry
*
Authors: Fernandes Karan , Ghosh Debodirna , Virmani Amitabh 
Published: December 2020

Abstract
The extreme Reissner–Nordström (ERN) solution has a discrete conformal isometry that maps the future event horizon to future null infinity and vice versa, the Couch–Torrence (CT) inversion isometry. We study the dynamics of a probe Maxwell field on the ERN solution in light of this symmetry. We present a gauge fixing that is compatible with the inversion symmetry. The gauge fixing allows us to relate the gauge parameter at the future horizon to future null infinity, which further allows us to study global charges for large gauge symmetries in the exterior of the ERN black hole. Along the way, we construct Newman–Penrose and Aretakis like conserved quantities along future null infinity and the future event horizon, respectively, and relate them via the CT inversion symmetry.
Mathematical and electronic model resistance/capacitor circuit of the action potential in an excitable cell
Authors: Vértiz-Hernández Juan Alberto , Vértiz-Hernández Angel Antonio , de Jesús Rangel-López Azahel , Campos-Cantón Isaac 
Published: December 2020

Abstract
Excitable cells are those that, when stimulated, generate an ion-dependent action potential; between them are neurons. The action potential has been a relevant target of study concerning cellular communication and behavior. This work aims to implement and validate the action potential of an excitable cell through resistance/capacitor (RC) circuits based on a mathematical/electrical model. This perspective can help researchers understand an excitable cell’s action potential from a mathematical and electrical approximation using a simple model. The experiment was designed based on RC circuits associated with the ionic channels of sodium (Na+) and potassium (K+). The proposed model also incorporates the ‘dendrite’ action not employed in the Hodgkin and Huxley model. Thus, a linear function by parts was used in mathematical modeling, recreating the excitable cell’s behavior through numerical and electronic simulation. The proposed mathematical/electrical model includes dendrites and capacitors not considered in previous models. In this scheme, the dendrite joined to the RC circuit describes the behavior as physiological, concerning the action potentials and the ions responsible.
Effects of conceptual and contextual task characteristics on students’ activation of mechanics conceptions
Authors: Just Anna M , von Aufschnaiter Claudia , Vorholzer Andreas 
Published: December 2020

Abstract
For promoting student learning in Newtonian mechanics, tailoring instruction to students’ conceptual needs is important. Although students’ conceptions can be inferred from research results, planning instruction is challenged by the fact that students may activate different conceptions for similar mechanics phenomena. For instance, changing the context or the wording of a task can evoke different conceptions. This article describes an approach to understanding how specific conceptual task characteristics (variations in the underlying concept or how the concept is approached) and contextual task characteristics (variations in the situation to which a concept applies) correlate with the activation of students’ conceptions in Newtonian mechanics. We employed a total of 72 single-choice tasks varying systematically conceptual and contextual task characteristics. Tasks were distributed over four test booklets and administered to a sample of undergraduates with physics as a major (N = 85) and minor subject (N = 114) as well as to high school students (age: ∼ 16, N = 157). Inferential statistical analysis was conducted to investigate if tasks with specific characteristics differed in their mean solution probabilities, revealing varying conceptions. Our findings suggest that even slight differences in how a task is situated (contextual characteristics), which law it addresses, and whether we ask for forces or for the state of motion (conceptual characteristics) result in significant differences regarding activated conceptions. For example, for Newton’s 1st law (with v = const. but ≠ 0) students activate more appropriate conceptions (higher solution probability) when tasks describe forces and ask for the resulting motion than vice versa. For planning instruction, it seems to be important to pay attention to the task characteristics used, to select them consciously, and to explicitly compare tasks that vary according to a particular characteristic.
An ultrafast response and precisely controllable soft electromagnet actuator based on Ecoflex rubber film filled with neodymium-iron-boron
Authors: Wang Xinli , Zhang Qian , Liu Ping , Zhu Xun , Wu Chen , Wang Jinyu , Liu Caixia , Wang Junfeng , Gao Yang , Song Aiguo , Huang Ying 
Published: December 2020

Abstract
Soft actuator is widely applied in soft grasp and artificial actuation. However, the characteristics of fast response and precise controllability are challenges for soft actuators. In this report, an ultrafast response and precisely controllable soft electromagnet actuator based on Ecoflex rubber film filled with neodymium-iron-boron is proposed. After optimizing the matrix and size of the actuator, the flexible magnetic actuator shows many merits including ultrafast response (<0.1 s), large elongation (<120%), excellent working stability, precision for long time working and customized designs. Based on customized patterns, different kinds of grippers have been made and they can realize the function of grasp and clutching of spherical and cylindrical objects. Furthermore, this actuator can be used on designed devices to build a pump system which can implement liquid injection and liquid blend. The proposed soft actuator has a great prospect in the practical application such as medical devices and soft robotics.
Intrinsic ferromagnetic semiconductors in rhombohedral RMnO3 (R = Sc, Y, and Lu) with high critical temperature and large ferroelectric polarization
Authors: Zhang Chengfeng , Li Zixu , Li Guannan , Gao Benling , Liang Feng , Li Zhongwen , Song Guang 
Published: December 2020

Abstract
Ferromagnetic (FM) semiconductors have been recognized as the cornerstone for next-generation highly functional spintronic devices. However, the development in practical applications of FM semiconductors is limited by their low Curie temperatures (T
C). Here, on the basis of model analysis, we find that the FM super-exchange couplings in the d
5 − d
3 system can be significantly strengthened by reducing the virtual exchange gap (G
ex) between occupied and empty e

g
orbitals. By first-principle calculations, we predict robust ferromagnetism in three rhombohedral RMnO3 (R = Sc, Y, and Lu) compounds with the T
C that is as high as ∼1510 K (YMnO3). The oxygen breathing motions open a band gap and create an unusual Mn2+/Mn4+ charge ordering of the Mn-d electrons, which play an important role in altering the G
ex. Interestingly, the rhombohedral RMnO3 compounds are also ferroelectric (FE) with a large spontaneous polarization approaching that of LiNbO3. These results not only deepen the understandings of magnetic couplings in d
5 − d
3 system, but also provide a way to design room-temperature FM–FE multiferroics.
GLONASS precise orbit determination based on L-band and SLR data
Authors: Yang Honglei , Xu Tianhe , Nie Wenfeng , Fang Zhenlong , Li Min , Guan Meiqian 
Published: December 2020

Abstract
Precise orbit determination (POD) plays an important and fundamental role in Global Navigation Satellite System (GNSS) applications. The Russian GLONASS is a mature full-constellation GNSS system that provides both L-band and satellite laser ranging (SLR) data. To explore the current individual GLONASS POD capability, we conduct the multi-day solution of the GLONASS L-band, SLR-only, and the combined L-band/SLR POD from 1 to 30 September, 2019. Seven strategies are investigated to explore the impact of the multi-day solution strategy on the GLONASS SLR-only POD. For the L-band POD, we find that the 3 d solution is always optimal without the influence of the eclipse. The overall average root mean square (rms) values are 3.7, 4.1 and 4.7 cm in the radial-tangential-normal (RTN) directions by comparison with the Center for Orbit Determination in Europe (CODE) orbits. The corresponding RTN rms values are 1.2, 4.3 and 3.4 cm for the orbital overlaps. For the SLR-only POD, the 9 d solution is the best with the orbital overlap RTN rms values of 0.7, 4 and 5.7 cm. Meanwhile, the RTN rms values are 1.6, 8 and 14 cm for the CODE orbits, which is obviously better than those of the L-band orbits in the R-direction. Due to the inaccuracy of the estimated dynamic parameters, the orbital consistency degrades with the increase of the multi-day solution arcs. Last but not least, a slight improvement in accuracy can be achieved in the combined L-band/SLR POD, especially in the R-direction of the 1 d solution. As a typical case, the external consistency is improved by 0.4–1.2, −0.3–1.7 and 0.1–1.5 cm in the RTN directions for the 3 d solution of the GLONASS R14 during the day of the year 256–265, 2019.
Development of robustness evaluation strategies for enabling statistically consistent reporting
Authors: Sterpin E , Rivas Sara T , Van den Heuvel F , George B , Lee J A , Souris K 
Published: December 2020

Abstract
Robustness evaluation of proton therapy treatment plans is essential for ensuring safe treatment delivery. However, available evaluation procedures feature a limited exploration of the actual robustness of the plan and generally do not provide confidence levels. This study compared established and more sophisticated robustness evaluation procedures, with quantified confidence levels. We have evaluated several robustness evaluation methods for 5 bilateral head-and-neck patients optimized considering spot scanning delivery and with a conventional CTV-to-PTV margin of 4 mm. Method (1) good practice scenario selection (GPSS) (e.g. +/− 4 mm setup error 3% range uncertainty); (2) statistically sound scenario selection (SSSS) either only on or both on and inside isoprobability hypersurface encompassing 90% of the possible errors; (3) statistically sound dosimetric selection (SSDS). In the last method, the 90% best plans were selected according to either target coverage quantified by D
95 (SSDS_D
95) or to an approximation of the final objective function (OF) used during treatment optimization (SSDS_OF). For all methods, we have considered systematic setup and systematic range errors. A mix of systematic and random setup errors were also simulated for SSDS, but keeping the same conventional margin of 4 mm. All robustness evaluations have been performed using the fast Monte Carlo dose engine MCsquare. Both SSSS strategies yielded on average very similar results. SSSS and GPSS yield comparable values for target coverage (within 0.5 Gy). The most noticeable differences were found for the CTV between GPSS, on the one hand, and SSDS_D
95 and SSDS_OF, on the other hand (average worst-case D
98 were 2.8 and 2.0 Gy larger than for GPSS, respectively). Simulating explicitly random errors in SSDS improved almost all DVH metrics. We have observed that the width of DVH-bands and the confidence levels depend on the method chosen to sample the scenarios. Statistically sound estimation of the robustness of the plan in the dosimetric space may provide an improved insight on the actual robustness of the plan for a given confidence level.
A semi-empirical model for scatter field reduction in digital mammography
Authors: Marimón E , Marsden P A , Nait-Charif H , Díaz O 
Published: December 2020

Abstract
X-ray mammography is the gold standard technique in breast cancer screening programmes. One of the main challenges that mammography is still facing is scattered radiation, which degrades the quality of the image and complicates the diagnosis process. Anti-scatter grids, the main standard physical scattering reduction technique, have some unresolved challenges as they increase the dose delivered to the patient, do not remove all the scattered radiation and increase the cost of the equipment. Alternative scattering reduction methods based on post-processing algorithms, have lately been under investigation. This study is concerned with the use of image post-processing to reduce the scatter contribution in the image, by convolving the primary plus scatter image with kernels obtained from simplified Monte Carlo (MC) simulations. The proposed semi-empirical approach uses up to five thickness-dependant symmetric kernels to accurately estimate the scatter contribution of different areas of the image. Single breast thickness-dependant kernels can over-estimate the scatter signal up to 60%, while kernels adapting to local variations have to be modified for each specific case adding high computational costs. The proposed method reduces the uncertainty to a 4%–10% range for a 35–70 mm breast thickness range, making it a very efficient, case-independent scatter modelling technique. To test the robustness of the method, the scattered corrected image has been successfully compared against full MC simulations for a range of breast thicknesses. In addition, clinical images of the 010A CIRS phantom were acquired with a mammography system with and without the presence of the anti-scatter grid. The grid-less images were post-processed and their quality was compared against the grid images, by evaluating the contrast-to-noise ratio and variance ratio using several test objects, which simulate calcifications and tumour masses. The results obtained show that the method reduces the scatter to similar levels than the anti-scatter grids.
OCT4 expression in human embryonic stem cells: spatio-temporal dynamics and fate transitions
Authors: Wadkin L E , Orozco-Fuentes S , Neganova I , Lako M , Barrio R A , Baggaley A W , Parker N G , Shukurov A 
Published: December 2020

Abstract
The improved in vitro regulation of human embryonic stem cell (hESC) pluripotency and differentiation trajectories is required for their promising clinical applications. The temporal and spatial quantification of the molecular interactions controlling pluripotency is also necessary for the development of successful mathematical and computational models. Here we use time-lapse experimental data of OCT4-mCherry fluorescence intensity to quantify the temporal and spatial dynamics of the pluripotency transcription factor OCT4 in a growing hESC colony in the presence and absence of BMP4. We characterise the internal self-regulation of OCT4 using the Hurst exponent and autocorrelation analysis, quantify the intra-cellular fluctuations and consider the diffusive nature of OCT4 evolution for individual cells and pairs of their descendants. We find that OCT4 abundance in the daughter cells fluctuates sub-diffusively, showing anti-persistent self-regulation. We obtain the stationary probability distributions governing hESC transitions amongst the different cell states and establish the times at which pro-fate cells (which later give rise to pluripotent or differentiated cells) cluster in the colony. By quantifying the similarities between the OCT4 expression amongst neighbouring cells, we show that hESCs express similar OCT4 to cells within their local neighbourhood within the first two days of the experiment and before BMP4 treatment. Our framework allows us to quantify the relevant properties of proliferating hESC colonies and the procedure is widely applicable to other transcription factors and cell populations.
AGN Jets and a Fanciful Trio of Black Holes in the Abell 85 Brightest Cluster Galaxy
Authors: Madrid Juan P. 
Published: December 2020

Abstract
A new radio map of the Abell 85 Brightest Cluster Galaxy (BCG) was obtained with the Karl G. Jansky Very Large Array. With a resolution of 0.″02, this radio image shows two kiloparsec-scale bipolar active galactic nucleus jets emanating from the active galactic nucleus of the A85 BCG. The galaxy core appears as a single entity on the new radio map. It has been assumed that the A85 BCG contained a binary black hole in its core. However, Chandra X-ray data and the new high-resolution radio map show no evidence that the A85 BCG harbors a binary black hole. The assumption that this galaxy contains a binary black hole was based on the analysis of its optical surface brightness profile obtained under poor seeing conditions. We demonstrate how the well-known blurring effects of atmospheric seeing can mimic the effects of a binary supermassive black hole (SMBH). Likewise, SDSS J004150.75–091824.3 was postulated to be “a third” SMBH associated with the BCG. In the optical and X-rays, SDSS J004150.75–091824.3 is a point-like source located ∼14″ away from the nucleus of the A85 BCG. A new spectrum of SDSS J004150.75–091824.3, obtained with the 10.4 m Gran Telescopio Canarias, reveals that this source is a background quasar at a redshift of z = 1.5603 ± 0.003 and not associated in any way with the A85 cluster.
Online asynchronous detection of error-related potentials in participants with a spinal cord injury using a generic classifier
Authors: Lopes-Dias Catarina , Sburlea Andreea I , Breitegger Katharina , Wyss Daniela , Drescher Harald , Wildburger Renate , Müller-Putz Gernot R 
Published: December 2020

Abstract
For brain–computer interface (BCI) users, the awareness of an error is associated with a cortical signature known as an error-related potential (ErrP). The incorporation of ErrP detection into BCIs can improve their performance. Objective. This work has three main aims. First, we investigate whether an ErrP classifier is transferable from able-bodied participants to participants with a spinal cord injury (SCI). Second, we test this generic ErrP classifier with SCI and control participants, in an online experiment without offline calibration. Third, we investigate the morphology of ErrPs in both groups of participants. Approach. We used previously recorded electroencephalographic data from able-bodied participants to train an ErrP classifier. We tested the classifier asynchronously, in an online experiment with 16 new participants: 8 participants with SCI and 8 able-bodied control participants. The experiment had no offline calibration and participants received feedback regarding the ErrP detections from the start. To increase the fluidity of the experiment, feedback regarding false positive ErrP detections was not presented to the participants, but these detections were taken into account in the evaluation of the classifier. The generic classifier was not trained with the user’s brain signals. However, its performance was optimized during the online experiment by the use of personalized decision thresholds. The classifier’s performance was evaluated using trial-based metrics, which considered the asynchronous detection of ErrPs during the entire trial’s duration. Main results. Participants with SCI presented a non-homogenous ErrP morphology, and four of them did not present clear ErrP signals. The generic classifier performed better than chance in participants with clear ErrP signals, independently of the SCI (11 out of 16 participants). Three out of the five participants that obtained chance level results with the generic classifier would have not benefitted from the use of a personalized classifier. Significance. This work shows the feasibility of transferring an ErrP classifier from able-bodied participants to participants with SCI, for asynchronous detection of ErrPs in an online experiment without offline calibration, which provided immediate feedback to the users.