bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved analog switching characteristics of Ta2O5-based memristor using indium tin oxide buffer layer for neuromorphic computing
Authors: Lee Tae Sung , Choi Changhwan 
Published: February 2022

Abstract
A memristor is defined as a non-volatile memory switching two-terminal resistor, and a memristor with digital switching characteristics is widely studied as a next-generation non-volatile memory because of its simple structure, high integration density, and low power consumption. Recently, analog memristors with gradual resistance switching (RS) characteristics have garnered great attention because of their potential to implement artificial synapses that can emulate the brain functions. Transition metal oxides are thought to be strong candidate materials for the RS. In particular, tantalum oxide (TaO
x
)-based memristive devices provide stable and durable switching characteristics. TaO
x
-based memristors utilize analog switching characteristics and have excellent durability and reliability, so they can be applied as artificial synaptic device. In this study, the characteristics of analog RS using Ta2O5-based memristive devices were investigated. The current level of the Pt/Ta2O5/Pt memristors was improved by adjusting the thickness of Ta2O5. In particular, when an indium-tin-oxide (ITO) buffer layer was added to Ta2O5 forming a Pt/ITO/Ta2O5/Pt heterostructured double-layer device, it showed more symmetrical potentiation and depression characteristics under both polarities than a single-layer device without ITO layer. The symmetrical and linear potentiation and depression characteristics are essential for the development of efficient memristor-based neuromorphic systems. Insertion of the ITO buffer layer improves linearity, symmetry, and stability of the analog RS properties of Ta2O5-based memristors to artificial synapses.
Density functional theory study of nitrogen-doped black phosphorene doped with monatomic transition metals as high performance electrocatalysts for N2 reduction reaction
Authors: Liu Xin , Li Chenyin , Xu Fang , Fan Guohong , Xu Hong 
Published: February 2022

Abstract
Ammonia (NH3) is an essential resource in human production and living activities, and its demand has been rising in recent years. The catalytic synthesis of NH3 from N2 under mild conditions, inspired by biological nitrogen fixation, has piqued the interest of researchers. In this paper, density functional theory (DFT) calculations were used to investigate the catalytic activity, mechanism, and selectivity of the TM embedded nitrogen-doped phosphorene as high-performance nitrogen reduction reaction (NRR) electrocatalysts in depth. The results show that Nb- and Mo-doped catalysts present excellent catalytic performance, with low limiting potentials of −0.41 and −0.18 V, respectively. The Mo–N3–BP catalyst, for example, not only has an extremely low overpotential (−0.02 V), but also presents superior selectivity to effectively inhibit the HER competition reaction. A deeper look into the catalytic mechanism reveals a volcano relationship between the d-band center and the catalytic activity (Mo and Nb are located near the peak of the volcano-type curve). The d-band center and charge of the metal center can be regarded as effective descriptors for NRR activity on TM embedded nitrogen-doped phosphorene electrocatalysts, which hope to serve as a guiding principle for the design of high performance NRR single-atom catalyst in the future.
In-out charge exchange measurements and 3D modelling of diagnostic thermal neutrals to study edge poloidal impurity asymmetries
Authors: Cruz-Zabala D J , Viezzer E , Plank U , McDermott R M , Cavedon M , Fable E , Dux R , Cano-Megias P , Pütterich T , van Vuuren A Jansen , Garcia-Munoz M , Garcia Lopez J 
Published: February 2022

Abstract
A new method was developed to model the neutral population produced by the gas puff based charge exchange recombination spectroscopy systems at ASDEX Upgrade (AUG). With this method, the edge impurity density on the high field side (HFS) and low field side (LFS) can be obtained without the need to apply a neutral beam injection system. The neutral penetration needed for the calculation of the impurity density is obtained with a new gas puff module implemented in the FIDASIM code. The LFS impurity density profile evaluated with the new gas puff module matches the impurity density calculated with standard beam-based charge exchange diagnostics. Impurity temperature, rotation and density profiles at the HFS and LFS of an AUG H-mode discharge are presented. Edge impurity toroidal and poloidal flows show asymmetric structures. The impurity density asymmetries obtained with the new gas puff module are consistent with the observed flow structure.
Intrinsically shunted NbN/TaN/NbN Josephson junctions on Si substrates for large-scale integrated circuits applications
Authors: Yan Kaixin , Zhang Lu , Zhong Yulong , Shi Jiasheng , Shi Weifeng , Wu Ling , Wang Huiwu , Chen Lei , Ren Jie , Peng Wei , Wang Zhen 
Published: February 2022

Abstract
Superconducting circuits based on Josephson junctions have the potential to achieve high speed and ultra-low power consumption, but their integration is limited by the low controllability of Nb-based tunnel junction and the existence of shunt resistors. In this work, we report the fabrication of superconductor/normal metal/superconductor (SNS) Josephson junctions with high reproducibility on oxidized Si substrates. The junctions based on NbN/TaN/NbN trilayers measured at 4.2 K show excellent Josephson properties with a wide range of critical current (I
c) from 227 to 2000 μA. The variations of critical current density (J
c) and characteristic voltage (V
c) are respectively less than 7.1% and 7.5% in the 2 inch region. The standard deviation of I
c is calculated to be less than 1.7% for Josephson arrays with the number of junctions up to 10 000 occupying an area of 0.34 mm2. The results provide a guarantee for the applications of NbN-SNS Josephson junctions in superconducting large-scale integrated circuits.
A graphene inspired electromagnetic superlens
Authors: Lannebère Sylvain , Silveirinha Mário G 
Published: February 2022

Abstract
In this paper we propose a new paradigm to create superlenses inspired by n–p–n junctions of graphene. We show that by adjoining an n-type region and a p-type region with a crystal dislocation, it is possible to mimic the interaction of complementary Hamiltonians and achieve subwavelength imaging. We introduce an effective model of the system, and show that it predicts perfect lensing for both propagating and evanescent waves due to the excitation of a resonant mode at the interface between each region. This phenomenon is the consequence of a nontrivial boundary condition at the n–p interfaces due to a dislocation of the graphene ‘atoms’. We discuss practical realizations of such superlenses in electronic and photonic platforms. Using full wave simulations, we study in detail the performance of a photonic realization of the lens based on a honeycomb array of dielectric cylinders embedded in a metal.
Slow light frequency reference cavities—proof of concept for reducing the frequency sensitivity due to length fluctuations
Authors: Horvath Sebastian P , Shi Chunyan , Gustavsson David , Walther Andreas , Kinos Adam , Kröll Stefan , Rippe Lars 
Published: February 2022

Abstract
Length changes due to thermo-mechanical noise originating from, for example, Brownian motion are a key limiting factor of present day state-of-the-art laser frequency stabilization using Fabry–Pérot cavities. We present a laser-frequency stabilization concept using an optical cavity with a strong slow-light effect to reduce the impact of cavity length changes on the frequency stability. The resulting noise-reduction factor is proportional to the ratio between the light phase and group velocities in the highly dispersive cavity spacer. We experimentally demonstrate a proof-of-principle implementation of this laser-frequency stabilization technique using a rare-earth doped crystalline cavity spacer in conjunction with semi-permanent spectral tailoring to achieve precise control of the dispersive properties of the cavity. Compared to the same setup in the absence of the slow-light effect a reduction in frequency sensitivity of four orders of magnitude was achieved.
Symmetry analysis, optimal classification and dynamical structure of exact soliton solutions of (2+1)-dimensional modified Bogoyavlenskii–Schiff equation
Authors: Kumar Mukesh , Manju Kumari 
Published: February 2022

Abstract
The present research framework looks over complete sorted symmetry group classification and optimal subalgebras of (2+1)-dimensional modified Bogoyavlenskii-Schiff(mBSchiff) equation. It’s highly nonlinear and exhibits wave propagation in thermal pulse, sound wave, and bound particle. Using the invariance property of Lie groups, adequate infinitesimal symmetry of Lie algebra has been set up for the mBSchiff equation. A rigorous and systematized algorithm is carried out to obtain one optimal system based on the invariance feature of adjoint transformation. Further, symmetry reduction of the mBSchiff equation has been made to derive a system of ordinary differential equations with newly established similarity variables. The complete set of group invariant solutions for each corresponding subalgebras has been made. The derived solutions have diverse physical phenomena, which MATLAB simulation can quickly analyze. Thus, solutions presented here are kink, positon, soliton, doubly soliton, negaton, multisoliton types, which add on some meaningful physical aspects of the research.
A semi-supervised approach to dark matter
searches in direct detection data with machine learning
Authors: Herrero-Garcia Juan , Patrick Riley , Scaffidi Andre 
Published: February 2022

Abstract
The dark matter sector remains completely unknown. It is therefore crucial to keep an open mind regarding its nature and possible interactions. Focusing on the case of Weakly Interacting Massive Particles, in this work we make this general philosophy more concrete by applying modern machine learning techniques to dark matter direct detection. We do this by encoding and decoding the graphical representation of background events in the XENONnT experiment with a convolutional variational autoencoder. We describe a methodology that utilizes the `anomaly score' derived from the reconstruction loss of the convolutional variational autoencoder as well as a pre-trained standard convolutional neural network, in a semi-supervised fashion. Indeed, we observe that optimum results are obtained only when both unsupervised and supervised anomaly scores are considered together. A data set that has a higher proportion of anomaly score is deemed anomalous and deserves further investigation. Contrary to classical analyses, in principle all information about the events is used, preventing unnecessary information loss. Lastly, we demonstrate the reach of learning-focused anomaly detection in this context by comparing results with classical inference, observing that, if tuned properly, these techniques have the potential to outperform likelihood-based methods.
Testing the early universe with anisotropies of the gravitational wave background
Authors: Dimastrogiovanni Ema , Fasiello Matteo , Malhotra Ameek , Meerburg P. Daniel , Orlando Giorgio 
Published: February 2022

Abstract
In this work we analyse in detail the possibility of using small and intermediate-scale gravitational wave anisotropies to constrain the inflationary particle content. First, we develop a phenomenological approach focusing on anisotropies generated by primordial tensor-tensor-scalar and purely gravitational non-Gaussianities. We highlight the quantities that play a key role in determining the detectability of the signal. To amplify the power of anisotropies as a probe of early universe physics, we consider cross-correlations with CMB temperature anisotropies. We assess the size of the signal from inflationary interactions against so-called induced anisotropies. In order to arrive at realistic estimates, we obtain the projected constraints on the non-linear primordial parameter F
NL for several upcoming gravitational wave probes in the presence of the astrophysical gravitational wave background. We further illustrate our findings by considering a concrete inflationary realisation and use it to underscore a few subtleties in the phenomenological analysis.
Sputtering and reflection from a beryllium surface: effects of hydrogen isotope mass, impact position and surface binding energy
Authors: Shermukhamedov S. , Chen L. , Nazmutdinov Renat , Probst Michael 
Published: February 2022

Abstract
Atomistic simulations with machine-learned potential energy functions are employed for understanding the mechanisms driving the sputtering of beryllium by low-energy deuterium and tritium atoms and the details of their retention on pristine beryllium surfaces. The interaction between hydrogen/deuterium/tritium and beryllium surfaces regarding erosion yields is investigated by molecular dynamics simulations. The erosion yields of both hydrogen isotopes are similar for the same kinetic energies. Concentrating on deuterium, its impact on specific surface sites is analyzed. Finally, analytical expressions are used to predict the energy spectra of sputtered atoms.
Chondrogenic preconditioning of mesenchymal stem/stromal cells within a magnetic scaffold for osteochondral repair
Authors: Zhang Jiabin , Zhang Ming , Lin Rongcai , Du Yuguang , Wang Liming , Yao Qingqiang , Zannettino Andrew , Zhang Hu 
Published: February 2022

Abstract
Stem cell therapy using mesenchymal stem/stromal cells (MSCs) represents a novel approach to treating severe diseases, including osteoarthritis. However, the therapeutic benefit of MSCs is highly dependent on their differentiation state, which can be regulated by many factors. Herein, three-dimensional (3D) magnetic scaffolds were successfully fabricated by incorporating magnetic nanoparticles (MNPs) into electrospun gelatin nanofibers. When positioned near a rotating magnet (f = 0.5 Hz), the magnetic scaffolds with the embedded MSCs were driven upward/downward in the culture container, which induced mechanical stimulation to MSCs due to spatial confinement and fluid flow. The extracellular matrix-mimicking scaffold and the alternating magnetic field significantly enhanced chondrogenesis instead of osteogenesis. Furthermore, the fiber topography could be tuned with different compositions of the coating layer on MNPs, and the topography had a significant impact on MSC differentiation. Selective up-regulation of chondrogenesis-related genes (COL2A1 and ACAN) was found for the magnetic scaffolds with citric acid-coated MNPs (CAG). In contrast, osteogenesis-related genes (RUNX2 and SPARC) were selectively and significantly up-regulated for the magnetic scaffolds with polyvinylpyrrolidone-coated MNPs. Prior to implantation in vivo, chondrogenic preconditioning of MSCs within the CAG scaffolds under a dynamic magnetic field resulted in superior osteochondral repair. Hence, the magnetic scaffolds together with an in-house rotating magnet device could be a novel platform to initiate multiple stimuli on stem cell differentiation for effective repair of osteochondral defects.
Quantum algorithm for online convex optimization
Authors: He Jianhao , Yang Feidiao , Zhang Jialin , Li Lvzhou 
Published: February 2022

Abstract
We explore whether quantum advantages can be found for the zeroth-order online convex optimization (OCO) problem, which is also known as bandit convex optimization with multi-point feedback. In this setting, given access to zeroth-order oracles (that is, the loss function is accessed as a black box that returns the function value for any queried input), a player attempts to minimize a sequence of adversarially generated convex loss functions. This procedure can be described as a T round iterative game between the player and the adversary. In this paper, we present quantum algorithms for the problem and show for the first time that potential quantum advantages are possible for problems of OCO. Specifically, our contributions are as follows. (i) When the player is allowed to query zeroth-order oracles O(1) times in each round as feedback, we give a quantum algorithm that achieves

O

(

T

)

regret without additional dependence of the dimension n, which outperforms the already known optimal classical algorithm only achieving

O

(

n
T

)

regret. Note that the regret of our quantum algorithm has achieved the lower bound of classical first-order methods. (ii) We show that for strongly convex loss functions, the quantum algorithm can achieve O(log T) regret with O(1) queries as well, which means that the quantum algorithm can achieve the same regret bound as the classical algorithms in the full information setting.
Fragility fractures of the pelvis in the older population
Authors: Sivapathasuntharam Dhanupriya , Smith Gillian , Master Mohammed-Ashraf , Bates Peter 
Published: February 2022

Abstract
Pelvic fractures are an increasingly common injury seen in the older population and represent a significant burden of morbidity and mortality in this age group, as well as a large financial burden on the health service. It is well established that early fixation of femoral neck and acetabular fractures improves outcomes and increases the chances of patients returning close to their premorbid functional baseline. However, fixation of fragility fractures of the pelvis is less well established in current practice. There has been recent development of novel stabilisation techniques for unstable pelvic fractures, designed to tackle the difficulties associated with fixation in poor bone quality, along with medical trials of parathyroid hormone analogue treatment. However, it is still current practice to manage nearly all fragility fractures of the pelvis conservatively. In this article, we consider whether the development of surgical stabilisation techniques for pelvic fragility fractures may have the potential to improve the well-described morbidity and mortality associated with them.
Metabolomic markers of biological fluid in women with reproductive failure: a systematic review of current literatures
Authors: Zhang Yingying , Zhang Tao , Wu Ling , Li Tin Chiu , Wang Chi Chiu , Chung Jacqueline Pui Wah 
Published: February 2022

Abstract
Understanding metabolic changes in reproductive failure, including early miscarriage (EM), recurrent miscarriage (RM), and repeated implantation failure (RIF), may be beneficial to understand the pathophysiology, thus improving pregnancy outcomes. Nine metabolomic profiling studies in women with reproductive failures (4 for EM, 3 for RM, and 2 for RIF) were included for systematic review. In total 78, 75, and 25 significant metabolites were identified and 40, 40, and 34 metabolic pathways were enriched in EM, RM, and RIF, respectively. Among them, 7 and 11 metabolites, and 28 and 28 pathways were shared between EM and RM and between RM and RIF, respectively. Notably, histidine metabolism has the highest impact in EM; phenylalanine, tyrosine, and tryptophan biosynthesis. Ubiquinone and other terpenoid–quinone biosynthesis metabolism have the highest impact factor in RM; alanine, aspartate, and glutamate metabolism have the highest impact factor in RIF. This study not only summarized the common and distinct metabolites and metabolic pathways in different reproductive failures but also summarized limitations of the study designs and methodologies. Hence, further investigations and validations of these metabolites are still urgently needed to understand the underlying metabolic mechanism for the development and treatment of reproductive failures.
19 Plain Film X-Ray Reporting in Orthopaedic Patients: A Reaudit in a District General Hospital
Authors: Khaleeq T. , Shah Foridi J. , Reading J. 
Published: February 2022

Abstract

Aim
To assess clinical evaluation of plain film x-rays requested for patients in the orthopaedic department (clinic and ward)
Standards:
Ionising radiation (medical exposure) regulations irmer 2017 procedure j: recording clinical exposure, national guideline and local guidance is in keeping with irmer and good clinical practice.

Method
50 plain films of randomly selected (using random number generator) who had attended new patient fracture clinic and ward. An initial audit was done in June and an reaudit in September.
The radiology system, clinical notes and clinic letters were reviewed to obtain the relevant data.

Results
Audit: 20 films were documented
30 were not documented
Reaudit
32 films were documented by referring clinician
18 films were not documented by referring clinician
Audit:
Clinical evaluation documented 18
Clinical evaluation not documented 32
Reaudit:
Clinical evaluation documented - 29
Clinical evaluation not documented - 21

Discussion
Whose responsibility? Radiographs commented on in trauma meetings not documented. New radiographs not commented on in clinic.
Limitations - access to more notes from ward.

Conclusions
As outlined in guidance orthopaedic and fracture clinic plain films should be reported by referring clinician or their team. Currently this is being done 64% of the time, significant improvement was seen. This may have medicolegal consequences as it does not follow GMC guidance for good medical practise.

Recommendations
Clinicians to specifically dictate x-ray findings in fracture clinic. Junior staff to take responsibility for documenting x-ray findings as discussed with senior clinicians for trauma patients. Junior staff to review post-op x-rays for all patients and to document.
56 A Quality Improvement Project to Assess and Refine the Handover Process at Morning Trauma Meetings
Authors: Sadiq S. , Tahir M. , Elerian S. , Baker D. , Bruce A. , Nur I. , Malik A. 
Published: February 2022

Abstract

Aim
Poor handover and inadequate transmission of clinical information between shifts can result in patient harm. This study was designed to evaluate the impact of implementing a handover protocol on the quality of information exchanged in the trauma handover meetings in a UK district general hospital.

Method
A prospective single centre observational study was performed at an acute NHS trust, using the define, measure, analyse, improve and control (DMAIC) methodology. Ten consecutive weekday trauma meetings, involving 43 patients, were observed to identify poor practices in handover. This data was used in conjunction with the Royal College of Surgeon’s recommendations for effective handover (2007) to create a standard operating protocol (SOP). Following the implementation of the SOP, a further eight consecutive weekday trauma meetings, involving a further 47 patients, were observed. The data collection was performed by five trained independent observers. The data was analysed using t-test for quantitative variables and chi-square or Fisher’s exact tests for categorical variables.

Results
An improvement in the trauma handover was demonstrated in multiple aspects of handover including patient’s past medical history, injury date, results, diagnosis, consent, mark and starvation status (all p &lt; 0.001). Subgroup analyses showed that handover of neck of femur patients including information on mobility (p = 0.04), Nottingham Hip Fracture Score (p = 0.01), next of kin discussion (p = 0.075) and resuscitation status (p = 0.001) all improved following our interventions.

Conclusions
These results demonstrate that the implementation of a well-structured handover protocol can improve the transmission of critical information in trauma meetings.