bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increasing Incidence of Sternoclavicular Joint Infections in Intravenous Drug Users
Authors: Orbay Hakan , Seng Sirivan , Kim Daniel Wonsuk , Geller Charles M. 
Published: January 2022

AbstractSternoclavicular joint septic arthritis is rarely seen in the general population. The majority of cases are seen in intravenous drug users. Given the lack of reported cases in the literature, there is no standardized treatment algorithm for this disease. Described treatment methods range from medical management to wide local debridement. The incidence of sternoclavicular joint septic arthritis will likely continue to increase with rising usage of intravenous drugs in the United States. Within the past year, our institution treated four cases.
Technical Aspects of High-Resolution Color-Coded Duplex Sonography for the Design of Perforator Flaps
Authors: Kehrer Andreas , Heidekrueger Paul I. , Lonic Daniel , Klein Silvan , Anker Alexandra , Taeger Christian D. , Biermann Niklas , Jung Ernst Michael , Prantl Lukas , da Silva Natascha Platz Batista 
Published: January 2022

Abstract
Background Technical aspects are of utmost significance for an efficient execution in designing perforator flaps with high-resolution color-coded Duplex sonography (CCDS). The following study evaluates decisive factors for a successful microvessel examination conducted by the microsurgeon.
Methods Technical knowledge presented in this study was based on a series of more than 200 perforator flaps planned with CCDS. Flap reconstructions were performed at the University Hospital Regensburg, Germany, from July 2013 to January 2021. Standard high-resolution ultrasound (US) devices with linear multifrequency transducers of 4 to 18 MHz were used. Modes and device settings were evaluated regarding applicability by microsurgeons. Key steps for safe perforator identification and further optional steps for additional assessment should be discriminated.
Results Different US modes including brightness mode (B-mode), color flow (CF), power Doppler (PD), pulse wave (PW), and blood flow (B-Flow) were used. Transducers from 15 MHz and up were favorable to detect microvessels. Knobology of a standard US device regarding buttons, switches, and specific onscreen options with relevance for perforator mapping was subcategorized in four different groups. For qualitative and quantitative evaluation of microvessels, different US modes were tested with respect to their usefulness.Vital elements of the CCDS exam are disaggregated into three key steps for safe perforator identification and three optional steps for further perforator characterization. A standardized protocol for the CCDS exams was applied. Downregulation of pulse-repetition frequency/scale to adapt device sensitivity to slow-flow velocities represented the most important criterion to visualize microvessels.Qualitative microvessel evaluation was performed in B-mode, CCDS, PD mode, and B-Flow mode. Quantitative assessment was executed using PW-mode and CCDS measuring the microvessels' diameter (mm) and flow characteristics. Quantitative information may be obtained using PW-mode and the distance-measuring tool in CF-mode.
Conclusion Technical aspects with respect to proper device trimming and application decisively impact CCDS-guided perforator vessel identification and evaluation.
Learning through digital technologies among pre-primary school children
Authors: Butler Yuko Goto 
Published: January 2022

Abstract
In response to the growing global demand for teaching additional language(s) to very young children (ages 2–6), an increasing supply of digital technologies purports to assist pre-primary school children with their language learning. Focusing on TV/videos, digital picture books, and social robots, this paper examined the small body of empirical research on the effect of these digital technologies on very young second or foreign language learners and bolstered this research with similar studies conducted among very young children learning a first language. The paper identifies possibilities and limitations of using such technologies and documents how they can be used effectively with young language learners. Two key elements for effective use of digital technologies emerged from the examination of the relevant studies: (a) digital devices and applications must have developmentally appropriate content and functions; and (b) children need to have meaningful interaction with adults or digital agents while using digital technology. The paper concludes with two implications for future research: (a) the need to have critical discussions when designing digital technologies for and using digital technologies with young children; and (b) the need to pay greater attention to individual differences in children’s attitudes and preferences concerning different digital technologies.
Child-centred ethics in second language education
Authors: Pinter Annamaria 
Published: January 2022

Abstract
This article aims to provide an overview of the types of questions and concerns adult researchers working with children in L2 education need to consider when it comes to navigating research ethics. Questions and dilemmas relating to ethical practice in child-focussed research are complex, and will be rooted in political, legal and contextual concerns, and interpretations of what is ethical in any one project will depend on the adult researcher’s convictions about research paradigms, their epistemological stance and their beliefs and priorities in the given situation. This article suggests five main questions to consider when it comes to research with children. All five components are equally important and decisions relating to one component will influence all others in the framework. This paper examines the complexities in more detail, discusses some differences relevant in the two main ‘paradigms’ of child-focussed research and how these principles interact with the constraints and the affordances of the local contexts, the focus of the intended study and the background and personal theories of the adult researcher.
Bilateral key comparison EURAMET.EM-K11.1 "AC-DC Voltage Transfer Difference at Low Voltages"
Authors: Renner Jeannine , Heine Gernot , Waldmann Wolfgang 
Published: January 2022

Main text
To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.
The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Part I. Nanobubbles in pulsed laser fields for anticancer therapy: in search of adequate models and simulation approaches
Authors: Kostyukov A S , Isaev I L , Ershov A E , Gerasimov V S , Polyutov S P , Karpov S V 
Published: January 2022

Abstract
We numerically investigate the conditions for the laser-induced formation of nanobubbles in aqueous medium around plasmonic nanoparticles (NPs) bound to the malignant cell membranes that is considered as the method of their irreversible damage. We proposed employing the versatile and accessible simulation software as a research tool based on the finite volume method underlying the ANSYS Fluent package and supplemented with our user-defined functions that adapt it to solution of the stated problems. This adaptation allows to verify the model using experimental data for the same conditions. We determined the conditions for the pressure growth on the cell membrane at the initial moment of bubble formation significantly exceeding the threshold of irreversible damage. The model can be used for investigation of hydrodynamic effects accompanying irradiation of plasmonic NPs using both different types of pulsed lasers and ideally absorbing NPs with resonance in the hemoglobin spectral transparency range, as well as to uncover previously unknown effects. They include the conditions for localization of a damaging factor non-affecting the normal cells, the conditions for generation of ultrahigh pressure pulse that enables to damage the cell membrane and precedes formation of thin vapor shell around NPs, which, unlike large bubbles, requires registration using highly sensitive experimental measurements. An extensive overview of key publications summarizing the state-of-art in this area is presented.
Topological magnetic hysteresis in single crystals of CeAgSb2 ferromagnet
Authors: Prozorov Ruslan , Bud’ko Sergey L , Canfield Paul C 
Published: January 2022

Abstract
Closed-topology magnetic domains are usually observed in thin films and in an applied magnetic field. Here we report the observation of rectangular cross-section tubular ferromagnetic domains in thick single crystals of CeAgSb2 in zero applied field. Relatively low exchange energy, small net magnetic moment, and anisotropic in-plane crystal electric fields lower the domain wall energy and allow for the formation of the closed-topology patterns. The tubular domain structure irreversibly transforms into a dendritic pattern upon cycling the magnetic field. This transition between closed and open topologies results in a ‘topological magnetic hysteresis’— the actual hysteresis in magnetization, not due to the imperfections and pinning, but due to the difference in the pattern morphology. Similar physics was suggested before in pure type-I superconductors and is believed to be a generic feature of other nonlinear single (present case), or two-phase (type-I superconductor) systems where the effects similar to demagnetization (shape-dependent macroscopic variation of properties) lead to pattern formation.
Mitigating effects of sublethal and lethal whole-body gamma irradiation in a mouse model with soluble melanin
Authors: Malo Mackenzie E , Frank Connor , Khokhoev Elbrus , Gorbunov Andrey , Dontsov Alexander , Garg Ravendra , Dadachova Ekaterina 
Published: January 2022

Abstract
The field of radiation countermeasures is growing, however, currently there are no effective and non-toxic compounds which could be administered orally to the individuals post exposure to high doses of ionising radiation. The pigment melanin is ubiquitous through all kingdoms of life and provides selective advantage under radiation stress through its role as a chemical and physical shield, and its capacity to respond and react to exposures. Soluble allomelanin was administered to mice following whole-body exposure to lethal or sublethal doses of gamma radiation to determine its capacity to mitigate the effects of acute radiation syndrome, and its utility as a radiation countermeasure. Allomelanin has shown a trend to improve survival post an 8 Gy sublethal radiation exposure when administered up to 48 h post-irradiation. Furthermore, it improved median and overall survival to a 10 Gy lethal radiation exposure, specifically when administered at 24 h post-irradiation. Histological analysis on the jejunum region of the small intestine of this treatment group indicated that alterations of the mucosal and submucosal architecture, and disruption of the lymphatic system associated with lethal radiation exposure were mitigated when allomelanin was administered at 24 h post-irradiation. Based on this work soluble allomelanin derived from a fungal source could serve as an easily sourced, cost-effective, and viable countermeasure to accidental radiation exposure and merits further investigation.
Development of a thoron chamber for calibration of thoron monitors under natural wind speed conditions
Authors: Lv Lidan , He Zhengzhong , Xiao Detao , Qiu Shoukang 
Published: January 2022

Abstract
To examine the response of diffusion-type detectors for thoron under wind speeds similar to natural air ventilation, a special design thoron chamber was developed with a dynamic circulating air-flow field forced by fans. Wind speeds of 0–0.52 m s−1 were adjusted by control of the fan rotation rate according to a linear model, with higher wind speeds contributing to more homogenous air flow status. Thoron concentrations, ranging between 3.2 × 103 and 3.7 × 104 Bq m−3, were easily available through different injection conditions and 220Rn gas sources with high and stable emanation coefficient. The stability and homogeneity of thoron concentrations was controlled within 5.0% and the concentrations in the direction of wind speed had minimal differences compared with the other direction. Higher wind speeds also improved the stability and homogeneity of thoron concentrations. The design and construction of the thoron chamber functioned well in controlling thoron concentration. The response of an AlphaGUARD monitor to thoron was examined in the thoron chamber under different wind speeds. The study revealed a monitor response to thoron (rates of thoron infiltration into the detection chamber of the monitor) respectively was from 0.044 to 0.065 under winds speeds from 0.05 to 0.51 m s−1. Reproducible and controlled expourse conditions can be provided for testing thoron monitors.
A study on surface-temperature measurement by means of a vacuum-arc cathode under different current conditions
Authors: Yang Zongju , Dai Jingmin , Zhang Jianguo 
Published: January 2022

Abstract
Accurate detection and analysis of the cathode surface temperature delivers an important reference value as regards the prediction of electrode life and corrosion degree, a thorough study of the vacuum-breakdown phenomenon, design and application of the vacuum-arc ion source and vacuum switch. In this paper, multispectral true temperature measurement T of the surface temperature field of pulsed vacuum arc cathode materials under different discharge currents is carried out. Firstly, aiming at solving the problem of synchronous imaging measurement of the temperature field across the cathode of pulsed vacuum arc, a multi-wavelength monochromatic image-acquisition optical path is designed, based upon the image acquisition module of a high-speed monochrome camera. Also, multiple monochromatic spectral radiation images of the target are synchronously acquired on the focal plane of the same monochrome camera detector. As a result, the spectral-radiation image information of multiple wavelengths can be obtained in a single exposure time, which greatly shortens the temperature-field image acquisition time. Secondly, based upon the multispectral true-temperature calculation method, high-speed multispectral imaging measurement of the target temperature field is realized. Finally, the two-dimensional true temperature distribution of the cathode temperature field under different current conditions was studied by setting up an experimental platform for measuring the cathode temperature of the vacuum arc under different current conditions.
Experimentally validated x-ray image simulations of 50 μm x-ray PIV tracer particles
Authors: Parker Jason T , Mäkiharju Simo A 
Published: January 2022

Abstract
We evaluate Beer–Lambert (BL) ray-tracing and Monte Carlo N-Particle (MCNP) photon tracking simulations for prediction and comparison of x-ray imaging system performance. These simulation tools can aid the methodical design of laboratory-scale x-ray particle image velocimetry (XPIV) experiments and tracer particles by predicting image quality. Particle image signal-to-noise ratio (SNR) is used as the metric of system performance. Simulated and experiment data of hollow, silver-coated, glass sphere tracer particles (AGSF-33) are compared. As predicted by the simulations, the AGSF-33 particles are visible with a SNR greater than unity in 100 ms exposure time images, demonstrating their potential as x-ray PIV or particle tracking velocimetry (XPTV) tracers. The BL approach predicts the image contrast, is computationally inexpensive, and enables the exploration of a vast parameter space for system design. MCNP simulations, on the other hand, predict experiment images slightly more accurately, but are more than an order of magnitude more computationally expensive than BL simulations. For most practical XPIV system design applications, the higher computational expense of MCNP is likely not justified by the modest accuracy improvement compared to BL.
A statistical alternative to current measures of image quality in digital mammography
Authors: Caldwell D , Baldelli P , Phelan N , Kenny P 
Published: January 2022

Abstract

Objective. Mammogram image quality in European breast screening systems is defined by threshold gold thickness (T) assessment of the CDMAM contrast-detail phantom. Previous studies have outlined several limitations of the phantom including expense, number of images required and inter-phantom manufacturing variability. Two alternative approaches to image quality assessment for routine quality control are examined and compared to the CDMAM technique: (i) A detectability index (d′) based on a non-prewhitened model observer with an eye filter (NPWE) and (ii) A statistical estimate of contrast based on image noise levels (CSTAT
). Approach. The d′ calculation follows a previously published methodology based on the NNPS and contrast, both measured from an image of 5 cm of PMMA containing a 0.2 mm Al target, as well as the MTF measured under standard conditions. For the proposed statistical method, pixels in the centre of the same NNPS image were re-binned into a range of equivalent CDMAM target areas. For any area, the minimum contrast necessary to distinguish a signal from the background, CSTAT
, is 3.29σ at a 95% level of confidence, where σ is the standard deviation of the background pixels. Theoretical analysis predicts a simple relationships between CSTAT
, T and d′. Measured values of CSTAT
were compared to T and d′ as a function of air kerma at the detector for ten digital mammography systems from three different manufacturers. Main Results. Theoretical relationships between CSTAT

,
d′ and T were demonstrated. Minimum acceptable image quality performance for 0.10 and 0.25 mm diameter discs, defined by the European Guidelines in terms of T, are equivalent to d′ values of 0.85 and 5.36 and threshold CSTAT
values of 0.055 and 0.022. Significance. Strong correlations between log(T), log(d′) and log(CSTAT
) suggest that either alternative approach produces information corresponding to that obtained using the CDMAM. CSTAT
should be considered as a simple, objective and cost-effective alternative to routine image quality assessment in mammography.
Direct multi-dimensional Chebyshev polynomial based reconstruction for magnetic particle imaging
Authors: Droigk Christine , Maass Marco , Mertins Alfred 
Published: January 2022

Abstract
Magnetic Particle Imaging is a tomographic imaging technique that measures the voltage induced due to magnetization changes of magnetic nanoparticle distributions. The relationship between the received signal and the distribution of the nanoparticels is described by the system function. A common method for image reconstruction is using a measured system function to create a system matrix and set up a regularized linear system of equations. Since the measurement of the system matrix is time-consuming, different methods for acceleration have been proposed. These include modeling the system matrix or using a direct reconstruction method in time, known as X-space reconstruction. In this work, based on the simplified Langevin model of paramagnetism and certain approximations, a direct reconstruction technique for Magnetic Particle Imaging in the frequency domain with two- and three-dimensional Lissajous trajectory excitation is presented. The approach uses Chebyshev polynomials of second kind. During reconstruction, they are weighted with the frequency components of the voltage signal and additional factors and then summed up. To obtain the final nanoparticle distribution, this result is rescaled and deconvolved. It is shown that the approach works for both simulated data and real measurements. The obtained image quality is comparable to a modeled system matrix approach using the same simplified physical assumptions and no relaxation effects. The reconstruction of a 31 × 31 × 31 volume takes less than a second and is up to 25 times faster than the state-of-the-art Kaczmarz reconstruction. Besides, the derivation of the proposed method shows some new theoretical aspects of the system function and its well-known observed similarity to tensor products of Chebyshev polynomials of second kind.
Multi-channel convolutional analysis operator learning for dual-energy CT reconstruction
Authors: Perelli Alessandro , Alfonso Garcia Suxer , Bousse Alexandre , Tasu Jean-Pierre , Efthimiadis Nikolaos , Visvikis Dimitris 
Published: January 2022

Abstract

Objective. Dual-energy computed tomography (DECT) has the potential to improve contrast and reduce artifacts and the ability to perform material decomposition in advanced imaging applications. The increased number of measurements results in a higher radiation dose, and it is therefore essential to reduce either the number of projections for each energy or the source x-ray intensity, but this makes tomographic reconstruction more ill-posed. Approach. We developed the multi-channel convolutional analysis operator learning (MCAOL) method to exploit common spatial features within attenuation images at different energies and we propose an optimization method which jointly reconstructs the attenuation images at low and high energies with mixed norm regularization on the sparse features obtained by pre-trained convolutional filters through the convolutional analysis operator learning (CAOL) algorithm. Main results. Extensive experiments with simulated and real computed tomography data were performed to validate the effectiveness of the proposed methods, and we report increased reconstruction accuracy compared with CAOL and iterative methods with single and joint total variation regularization. Significance. Qualitative and quantitative results on sparse views and low-dose DECT demonstrate that the proposed MCAOL method outperforms both CAOL applied on each energy independently and several existing state-of-the-art model-based iterative reconstruction techniques, thus paving the way for dose reduction.
Artificial spin ice phase-change memory resistors
Authors: Caravelli Francesco , Chern Gia-Wei , Nisoli Cristiano 
Published: January 2022

Abstract
We present a proposal for realization of an electrical memory reminiscent of a memristor in connected Kagome artificial spin ice. We show that current flowing through the system alters the magnetic ensemble, which in turns controls the overall resistance thus leaving memory of current passage in the system. This introduces a current-dependent effect for a dynamic resistive state. We simulate a spin-induced thermal phase-change mechanism, and an athermal domain-wall spin inversion. In both cases we observe electrical memory behavior with an I–V hysteretic pinched loop, typical of memristors. These results can be extended to the more complex geometries in which artificial spin ice can be designed to engineer the hysteresis curve.
On the origin and the detection of characteristic axion wiggles in photon spectra
Authors: Kachelrieß M. , Tjemsland J. 
Published: January 2022

Abstract
Photons propagating in an external magnetic field may oscillate into
axions or axion-like particles (ALPs). Such oscillations will lead to
characteristic features in the energy spectrum of high-energy photons from
astrophysical sources that can be used to probe the existence of ALPs.
In this work, we revisit
the signatures of these oscillations and stress the importance of a proper
treatment of turbulent magnetic fields.
We implement axions into ELMAG,
a standard tool for modelling in a Monte Carlo framework the propagation
of gamma-rays in the Universe, complementing thereby
the usual description of photon-axion oscillations with a Monte Carlo
treatment of high-energy photon propagation and interactions.
We also propose an alternative method of detecting axions through
the discrete power spectrum using as observable
the energy dependence of wiggles in the photon spectra.