bluuebunny/crossref_metadata_2025_split huggingface dataset:
The changing class and educational composition of the UK political elite since 1945: implications for representation
Authors: Bukodi Erzsébet , Evans Geoffrey , Goldthorpe John H. , Hepplewhite Matthew 
Published: March 2024

AbstractDebates over the changing nature of the UK political elite have focused on questions of representation and the extent of class convergence between the leaderships of the Conservative and Labour parties. We present a new comprehensive survey of the class and educational composition of the membership of Conservative and Labour cabinets and shadow cabinets since 1945. Some convergence in the class composition of the leaderships is apparent, but intra-class differences in terms of sector and occupation point to persisting differences in adult experience in profit-making versus public/third sector organisations and in technical versus sociocultural professions. Educationally, there is a decline in the Conservative leadership in the numbers coming from elite private schools but not from private schools in general, and attendance at elite universities remains more common on the Conservative side. Changes in the class origins and previous employment of the Conservative leadership do not suggest any weakening in the party’s capacity to represent business interests. In contrast, while there has been no decline in the proportion of the Labour leadership from working-class origins, there has been an almost complete disappearance of those with adult experience of working-class life.
Earthquake conspiracy discussion on Twitter
Authors: Erokhin Dmitry , Komendantova Nadejda 
Published: March 2024

AbstractNatural disasters like earthquakes, and global crises like pandemics have historically captured the public’s imagination and prompted people to seek explanations. However, in times of limited information, these explanations can take the form of conspiracy theories, particularly regarding the origins or causes of such events. With the advent of social media conspiracy theories can spread quickly and easily, leaving little room for critical thinking. The focus of this study is the analysis of the so-called High-Frequency Active Auroral Research Program (HAARP) conspiracy, which explains earthquakes through the employment of secret weather control weapons. This study aims to answer the research question of how the discourse on the HAARP conspiracy theory changes over time, and what are the potential catalysts for heightened attention to this conspiracy theory. This study uses the Twitter API to collect tweet frequencies about this conspiracy from January 2022 through March 2023. The empirical data include over one million tweets on HAARP. The sentiment analysis of the HAARP conspiracy theory is applied to the tweets before, during, and after the 6th of February 2023 earthquake in Syria and Turkey. In addition, this study investigates possible triggers of the development of the HAARP tweet frequency. This study finds that the frequency of HAARP discussion increases following a high-impact earthquake. There is also a positive correlation between average tweet sentiment and the number of tweets, which could indicate that the discussion of HAARP reinforces people’s beliefs. This study makes a significant contribution to the field of social psychology and communication by providing insights into the dynamics of belief reinforcement within online communities amidst heightened attention to conspiracy theories triggered by significant events. This knowledge has broader implications for understanding the impact of social media on public perception during crises.
Sequestration of helium and xenon via iron-halide compounds in early Earth
Authors: Zhang Jurong , Liu Hanyu , Chen Changfeng , Ma Yanming 
Published: March 2024

The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements, which has led to great interest in searching for materials that can host these usually unreactive elements. Here, using an advanced crystal structure search approach in conjunction with first-principles calculations, we show that several Xe/He-bearing iron halides are thermodynamically stable in a broad region of P–T phase space below 60 GPa. Our results present a compelling case for sequestration of He and Xe in the early Earth and may suggest their much wider distribution in the present Earth than previously believed. These findings offer insights into key material-based and physical mechanisms for elucidating major geological phenomena.
Design, fabrication, and characterization of a high-sensitivity integrated quartz vibrating beam accelerometer
Authors: Li Cun , Xue Hong , Zhao Yulong 
Published: March 2024

This paper describes the design, fabrication, and characterization of a quartz vibrating beam accelerometer consisting of a metal spring–mass and quartz double-ended tuning forks (DETFs). In this approach, the inertial force of the proof mass pulls or compresses the DETFs, affecting their resonance frequency and, thus, enabling the quasi-digital measurement of acceleration. An isolation structure was specifically designed to prevent the external interference stress from transforming into the DETFs and to decrease the DETFs’ thermal stress as the ambient temperature changes. A stress-free and high-precision wire-cut electrical discharge machining process was introduced to solve the fabrication problem of flexible hinges, and a femtosecond laser was used to release the proof mass, comprehensively considering the compatibility of the fabrication process and structural design. The oscillation excitation and detection of the DETFs were analyzed, and the DETFs were fabricated using a micro-electromechanical systems process. Sensor dimensions were optimized to improve sensor sensitivity. An accelerometer prototype was fabricated, and its performance was characterized. The tested scale factor was 157.28 Hz/g, and its stability was 16.54 ppm. The bias stability and 1 g stability at 1 h were 18 and 7.84 µg, respectively. The experimental results validated the feasibility of the sensor design.
A hybrid simulator with novel bicone-wire grid antenna
Authors: Li Shiji , Li Junna , Wu Fangzheng , Huang Qixiang , Gong Yuhan , Yang Tian , Liu Jian , Zhou Xiaoyu , Qiu Aici 
Published: March 2024

The simulator is an indispensable device for the study of high-altitude electromagnetic pulse (HEMP) effects. In order to improve the quality of the electric field waveforms of the HEMP simulator, we carried out simulation and experimental studies for the biconical-wire grid antenna. A new bicone-wire grid antenna HEMP simulator was designed by using skeletonized cones instead of solid cones, which can substantially improve the mobility of the simulator. The effects of different aspect ratios and different cone structures of the simulator on the waveform and distribution characteristics of the electric field were analyzed. The accuracy of the simulation results was verified by testing the bicone-wire grid antenna simulator with the new structure. The results obtained are as follows: First, the simulator can provide a HEMP environment compliant with the International Electrotechnical Commission (IEC) standard in an area of 5 × 6 × 2 m3. Second, the simulator possesses optimal waveform quality and working space among simulators with different aspect ratios. Finally, the influence of using skeletonized cones instead of solid cones on the simulator’s electric field waveforms is negligible, and the mobility of the new simulator is significantly improved compared to the original simulator.
Structural trends and itinerant magnetism of the new cage-structured compound HfMn2Zn20
Authors: Yasmin Nusrat , Noor Md Fahel Bin , Besara Tiglet 
Published: March 2024

Abstract
A new cage-structured compound—HfMn2Zn20—belonging to the AB
2
C
20 (A, B = transition or rare earth metals, and C = Al, Zn, or Cd) family of structures has been synthesized via the self-flux method. The new compound crystallizes in the space group

F
d

3
¯

m

with lattice parameter a ≈ 14.0543(2) Å (Z = 8) and exhibits non-stoichiometry due to Mn/Zn mixing on the Mn-site and an underoccupied Hf-site. The structure refines to Hf0.93Mn1.63Zn20.37 and follows lattice size trends when compared to other HfM
2Zn20 (M = Fe, Co, and Ni) structures. The magnetic measurements show that this compound displays a modified Curie-Weiss behavior with a transition temperature around 22 K. The magnetization shows no saturation, a small magnetic moment, and near negligible hysteresis, all signs of itinerant magnetism. The Rhodes–Wohlfarth ratio and the spin fluctuation parameters ratio both confirm the itinerant nature of the magnetism in HfMn2Zn20.
Ternary ReS2(1−x)Se2x
alloys of different composition for Q-switched and mode-locked all-fiber laser
Authors: Duan Xinghao , Zhang Zihao , Liu Kaixin , Wen Wen , Dong Yue , Wang Junli 
Published: March 2024

Abstract
This paper systematically studied the composition-controlled nonlinear optical properties and pulse modulation of ternary ReS2(1−x)Se2x
alloys for the first time. The compositionally modulated characteristics of ReS2(1−x)Se2x
on the band gap were simulated based on the first principles. We investigated the effect of the band gap on the saturable absorption properties. In addition, we demonstrated the modulation characteristics of different components ReS2(1−x)Se2x
on 1.5 μm Q-switched pulse performance. The Q-switched threshold, repetition rate, and pulse duration increase as the S(sulfur)-element composition rise. And pulse energy also was affected by the S(sulfur)-element composition. The ReS0.8Se1.2 SA was selected to realize a conventional soliton with high energy in the all-fiber mode-locked laser. The pulse was centered at 1562.9 nm with a pulse duration of 2.26 ps, a repetition rate of 3.88 MHz, and maximum pulse energy of 1.95 nJ. This work suggests that ReS2(1−x)Se2x
has great potential in laser technology and nonlinear optics, and widely extends the material applications in ultrafast photonics.
Using a hall sensor with GoGo board to determine angular speed and angular frequency
Authors: Intakaew Kanokporn , Wattanakasiwich Pornrat 
Published: March 2024

Abstract
This research focuses on modifying two physics experiments, a rotating wheel and a simple harmonic oscillator, to train pre-service physics teachers with an emphasis on digital and maker skills. The primary aims are twofold: first, to demonstrate the application of a Hall sensor, combined with the GoGo Board, in determining the angular speed in the rotating-wheel experiment and the angular frequency in the oscillation experiment. The second aim involves comparing these results with those obtained from high-speed video analysis using the Tracker software. To measure the period, a neodymium magnet was attached to both the wheel and mass. A block-based code was developed to control the Hall sensor and record the time when the magnet entered the detectable range of the sensor. In both experiments, high-speed videos at 250 fps were recorded and analysed using Tracker software. The study revealed that while the Hall sensor yields accurate measurements at lower speeds, its performance declines at higher speeds owing to limitations in accurately detecting the position of the magnet. In a simple harmonic oscillation experiment, the Hall sensor proved to be more effective at slower speeds. Although the Hall sensor approach resulted in a higher percentage error, it significantly enhanced students’ learning experience in terms of computational thinking and digital/maker skills.
Advancing medical imaging with language models: featuring a spotlight on ChatGPT
Authors: Hu Mingzhe , Qian Joshua , Pan Shaoyan , Li Yuheng , Qiu Richard L J , Yang Xiaofeng 
Published: March 2024

Abstract
This review paper aims to serve as a comprehensive guide and instructional resource for researchers seeking to effectively implement language models in medical imaging research. First, we presented the fundamental principles and evolution of language models, dedicating particular attention to large language models. We then reviewed the current literature on how language models are being used to improve medical imaging, emphasizing a range of applications such as image captioning, report generation, report classification, findings extraction, visual question response systems, interpretable diagnosis and so on. Notably, the capabilities of ChatGPT were spotlighted for researchers to explore its further applications. Furthermore, we covered the advantageous impacts of accurate and efficient language models in medical imaging analysis, such as the enhancement of clinical workflow efficiency, reduction of diagnostic errors, and assistance of clinicians in providing timely and accurate diagnoses. Overall, our goal is to have better integration of language models with medical imaging, thereby inspiring new ideas and innovations. It is our aspiration that this review can serve as a useful resource for researchers in this field, stimulating continued investigative and innovative pursuits of the application of language models in medical imaging.
Automation to facilitate optimisation of breast radiotherapy treatments using EPID-based in vivo dosimetry
Authors: Kirby Joshua , Chester Katherine 
Published: March 2024

Abstract

Objective. To use automation to facilitate the monitoring of each treatment fraction using an electronic portal imaging device (EPID) based in vivo dosimetry (IVD) system, allowing optimisation of breast radiotherapy delivery for individual patients and cohorts. Approach. A suite of in-house software was developed to reduce the number of manual interactions with the commercial IVD system, dosimetry check. An EPID specific pixel sensitivity map facilitated use of the EPID panel away from the central axis. Point dose difference and the change in standard deviation in dose were identified as useful dose metrics, with standard deviation used in preference to gamma in the presence of a systematic dose offset. Automated IVD was completed for 3261 fractions across 704 patients receiving breast radiotherapy. Main results. Multiple opportunities for treatment optimisation were identified for individual patients and across patient cohorts as a result of successful implementation of automated IVD. 5.1% of analysed fractions were out of tolerance with 27.1% of these considered true positives. True positive results were obtained on any fraction of treatment and if IVD had only been completed on the first fraction, 84.4% of true positive results would have been missed. This was made possible due to the automation that saved over 800 h of manual intervention and stored data in an accessible database. Significance. An improved EPID calibration to allow off-axis measurement maximises the number of patients eligible for IVD (36.8% of patients in this study). We also demonstrate the importance in selecting context-specific assessment metrics and how these can lead to a managable false positive rate. We have shown that the use of fully automated IVD facilitates use on every fraction of treatment. This leads to identification of areas for treatment improvement for both individuals and across a patient cohort, expanding the uses of IVD from simply gross error detection towards treatment optimisation.
Glioma segmentation based on dense contrastive learning and multimodal features recalibration
Authors: Hu Xubin , Wang Lihui , Wang Li , Chen Qijian , Zheng Licheng , Zhu Yuemin 
Published: March 2024

Abstract
Accurate segmentation of different regions of gliomas from multimodal magnetic resonance (MR) images is crucial for glioma grading and precise diagnosis, but many existing segmentation methods are difficult to effectively utilize multimodal MR image information to recognize accurately the lesion regions with small size, low contrast and irregular shape. To address this issue, this work proposes a novel 3D glioma segmentation model DCL-MANet. DCL-MANet has an architecture of multiple encoders and one single decoder. Each encoder is used to extract MR image features of a given modality. To overcome the entangle problems of multimodal semantic features, a dense contrastive learning (DCL) strategy is presented to extract the modality-specific and common features. Following that, feature recalibration block (RFB) based on modality-wise attention is used to recalibrate the semantic features of each modality, enabling the model to focus on the features that are beneficial for glioma segmentation. These recalibrated features are input into the decoder to obtain the segmentation results. To verify the superiority of the proposed method, we compare it with several state-of-the-art (SOTA) methods in terms of Dice, average symmetric surface distance (ASSD), HD95 and volumetric similarity (Vs). The comparison results show that the average Dice, ASSD, HD95 and Vs of DCL-MANet on all tumor regions are improved at least by 0.66%, 3.47%, 8.94% and 1.07% respectively. For small enhance tumor (ET) region, the corresponding improvement can be up to 0.37%, 7.83%, 11.32%, and 1.35%, respectively. In addition, the ablation results demonstrate the effectiveness of the proposed DCL and RFB, and combining them can significantly increase Dice (1.59%) and Vs (1.54%) while decreasing ASSD (40.51%) and HD95 (45.16%) on ET region. The proposed DCL-MANet could disentangle multimodal features and enhance the semantics of modality-dependent features, providing a potential means to accurately segment small lesion regions in gliomas.
A photon source model for alpha-emitter radionuclides
Authors: Sarrut D , Etxebeste A , Létang J M 
Published: March 2024

Abstract

Objective. A Monte Carlo virtual source model named PHID (photon from Ion decay) that generates photons emitted in the complex decay chain process of alpha-emitter radionuclides is proposed, typically for use during the simulation of SPECT image acquisition. Approach. Given an alpha-emitter radionuclide, the PHID model extracts from Geant4 databases the photon emission lines from all decaying daughters for both isometric transition and atomic relaxation processes. According to a given time range, abundances and activities in the decay chain are considered thanks to the Bateman equations, taking into account the decay rates and the initial abundances. Main results. PHID is evaluated by comparison with analog Monte Carlo simulation. It generates photons with the correct energy and temporal distribution, avoiding the costly simulation of the complete decay chain thus decreasing the computation time. The exact time gain depends on the simulation setup. As an example, it is 30× faster for simulating 1 MBq of 225Ac in water for 1 section Moreover, for 225Ac, PHID was also compared to a simplified source model with the two main photon emission lines (218 and 440 keV). PHID shows that 2 times more particles are simulated and 60% more counts are detected in the images. Significance. PHID can simulate any alpha-emitter radionuclide available in the Geant4 database. As a limitation, photons emitted from Bremsstrahlung are ignored, but they represent only 0.7% of the photons above 30 keV and are not significant for SPECT imaging. PHID is open-source, available in GATE 10, and eases the investigation of imaging photon emission from alpha emitters.
An automated technique for global noise level measurement in CT image with a conjunction of image gradient
Authors: Kuo Hsiang-Chi , Mahmood Usman , Kirov Assen S , Mechalakos James , Della Biancia Cesar , Cerviño Laura I , Lim Seng Boh 
Published: March 2024

Abstract
Automated assessment of noise level in clinical computed tomography (CT) images is a crucial technique for evaluating and ensuring the quality of these images. There are various factors that can impact CT image noise, such as statistical noise, electronic noise, structure noise, texture noise, artifact noise, etc. In this study, a method was developed to measure the global noise index (GNI) in clinical CT scans due to the fluctuation of x-ray quanta. Initially, a noise map is generated by sliding a 10 × 10 pixel for calculating Hounsfield unit (HU) standard deviation and the noise map is further combined with the gradient magnitude map. By employing Boolean operation, pixels with high gradients are excluded from the noise histogram generated with the noise map. By comparing the shape of the noise histogram from this method with Christianson’s tissue-type global noise measurement algorithm, it was observed that the noise histogram computed in anthropomorphic phantoms had a similar shape with a close GNI value. In patient CT images, excluding the HU deviation due the structure change demonstrated to have consistent GNI values across the entire CT scan range with high heterogeneous tissue compared to the GNI values using Christianson’s tissue-type method. The proposed GNI was evaluated in phantom scans and was found to be capable of comparing scan protocols between different scanners. The variation of GNI when using different reconstruction kernels in clinical CT images demonstrated a similar relationship between noise level and kernel sharpness as observed in uniform phantom: sharper kernel resulted in noisier images. This indicated that GNI was a suitable index for estimating the noise level in clinical CT images with either a smooth or grainy appearance. The study’s results suggested that the algorithm can be effectively utilized to screen the noise level for a better CT image quality control.
Implementation of a new EGSnrc particle source class for computed tomography: validation and uncertainty quantification
Authors: Kuhlmann Marie-Luise , Pojtinger Stefan 
Published: March 2024

Abstract

Objective. Personalized dose monitoring and risk management are of increasing significance with the growing number of computer tomography (CT) examinations. These require high-quality Monte Carlo (MC) simulations that are of the utmost importance for the new developments in personalized CT dosimetry. This work aims to extend the MC framework EGSnrc source code with a new particle source. This, in turn, allows CT-scanner-specific dose and image calculations for any CT scanner. The novel method can be used with all modern EGSnrc user codes, particularly for the simulation of the effective dose based on DICOM images and the calculation of CT images. Approach. The new particle source can be used with input data derived by the user. The input data can be generated by the user based on a previously developed method for the experimental characterization of any CT scanner (doi.org/10.1016/j.ejmp.2015.09.006). Furthermore, the new particle source was benchmarked by air kerma measurements in an ionization chamber at a clinical CT scanner. For this, the simulated angular distribution and attenuation characteristics were compared to measurements to verify the source output free in air. In a second validation step, simulations of air kerma in a homogenous cylindrical and an anthropomorphic thorax phantom were performed and validated against experimentally determined results. A detailed uncertainty evaluation of the simulated air kerma values was developed. Main results. We successfully implemented a new particle source class for the simulation of realistic CT scans. This method can be adapted to any CT scanner. For the attenuation characteristics, there was a maximal deviation of 6.86% between the measurement and the simulation. The mean deviation for all tube voltages was 2.36% (σ = 1.6%). For the phantom measurements and simulations, all the values agreed within 5.0%. The uncertainty evaluation resulted in an uncertainty of 5.5% (

k
=
1

).