bluuebunny/crossref_metadata_2025_split huggingface dataset:
3D-localization of single point-like gamma sources with a coded aperture camera
Authors: Meißner Tobias , Cerbone Laura Antonia , Russo Paolo , Nahm Werner , Hesser Jürgen 
Published: July 2024

Abstract

Objective. 3D-localization of gamma sources has the potential to improve the outcome of radio-guided surgery. The goal of this paper is to analyze the localization accuracy for point-like sources with a single coded aperture camera. Approach. We both simulated and measured a point-like

241

Am source at 17 positions distributed within the field of view of an experimental gamma camera. The setup includes a

0.11

mm

thick Tungsten sheet with a MURA mask of rank 31 and pinholes of

0.08

mm

in diameter and a detector based on the photon counting readout circuit Timepix3. Two methods, namely an iterative search including either a symmetric Gaussian fitting or an exponentially modified Gaussian fitting (EMG) and a center of mass method were compared to estimate the 3D source position. Main results. Considering the decreasing axial resolution with source-to-mask distance, the EMG improved the results by a factor of 4 compared to the Gaussian fitting based on the simulated data. Overall, we obtained a mean localization error of

0.77

mm

on the simulated and

2.64

mm

on the experimental data in the imaging range of

20

−

100

mm

. Significance. This paper shows that despite the low axial resolution, point-like sources in the nearfield can be localized as well as with more sophisticated imaging devices such as stereo cameras. The influence of the source size and the photon count on the imaging and localization accuracy remains an important issue for further research.
AC loss calculation of no-electrical-insulation HTS magnets using a field-circuit coupling method
Authors: Wang Ruichen , Ma Guangtong , Zhou Pengbo , Li Songlin , Liu Boqiang , Tian Weikang 
Published: July 2024

Abstract
No-electrical-insulation (NEI) magnets are gradually exhibiting significant appeal due to their robust thermal stability and elevated mechanical strength. However, when exposed to AC conditions, these magnets will suffer more significant AC losses in dynamic electromagnetic devices, such as motors and maglev systems. Presently, the numerical methods for predicting the electromagnetic and loss behavior of large-scale NEI magnets entail high computation costs due to the substantial degrees of freedom or complicated modeling strategies. Thus, we propose a fully finite element method, referred to as the field-circuit coupling method, to efficiently assess the overall behavior of NEI magnets while preserving adequate accuracy. This method couples the T-A formula and the single-turn equivalent circuit through a global voltage, to avoid the costly and complicated inductance calculations, and to simultaneously consider the induced current. By further integrating the homogenization method, the calculation speed can be increased up to ten times. Additionally, we study the critical current, and the electromagnetic and loss behavior of the NEI magnets based on the proposed model. We identify some measurement methods that offer more precise estimations of the critical current and the turn-to-turn contact resistance of NEI magnets. Meanwhile, the results indicate the severe impact of high AC fields on the losses, and emphasize the importance of a reliable shielding structure for operational safety. Finally, the influence of turn-to-turn contact resistivity on the loss behavior is also investigated, which can provide valuable insights for the design of NEI magnets in dynamic electromagnetic devices.
Regulating coordination environment around transition metal (Fe, Co) single atom catalysts for efficient Hg0 adsorption
Authors: Wang Ping , Gao Haoshan , Du Yaohui , Tang Miaomiao , Wang Kaitong , Zhao Yafei 
Published: July 2024

Abstract
Elemental mercury (Hg0) is one of the main pollutants released during coal combustion, which is difficult to remove due to its hydrophobicity and volatility, resulting in serious environmental pollution. Therefore, it is urgent to develop a low-cost and high-performance catalyst to remove Hg0. In this work, using first-principles study, the effect of nonmetal (NM = B, C and O) coordination environment on the charge distribution of graphene-supported transition metal single atom catalysts (TM-N4-SAC) has been investigated. It is found that regulating the TM-N4-SAC with NM coordination atoms with fewer valence electrons than N atom can cause TM atoms to lose more electrons, and the charge distribution in the active center to be locally deviated. Moreover, in-depth analysis of the adsorption configuration, charge density difference, charge transfer, adsorption energy and density of state of Hg0 adsorption on NM modified TM-N4-SAC confirmed that the adsorption of Hg0 can be effectively enhanced only when TM atoms lose more electrons. Thus, Fe-N3B- and Co-N3B-SAC have the strongest ability to adsorb Hg0 because they have the most negative adsorption energy of −1.13 and −0.49 eV. This work provides theoretical guidance for the design of SAC for efficient adsorption of Hg0.
Superluminality in parity-time symmetric Bragg gratings
Authors: Wu Li-Ting , Zhang Xin-Zhe , Guo Tian-Jing , Kang Ming , Chen Jing 
Published: July 2024

Abstract
Parity-time (

P
T

) symmetric Bragg gratings (PTBGs) possess unique features compared to traditional ones. For example, the photonic bandgap of a PTBG can be modified and even closed when the

P
T

symmetry evolves from an exact phase to a broken one, and the complex reflection coefficient of a PTBG is sensitive to the direction of incidence. In this article, we reveal how the superluminal effects of transmission behave following the modified band structure of PTBGs. The superluminality of the directionally sensitive reflection is also discussed. We then investigate the Hartman effect and argue that, to account for the superluminal effects in PTBGs, a directionally sensitive dwell time should be applied. This study offers unique insights into the mechanisms of superluminality and group delay of light in non-Hermitian open systems and contributes to the advancement of PTBGs, which can eventually become an indispensable platform for probing some of the exotic properties of optical wave phenomena and light–matter interactions.
Enhanced photocatalytic activity of Ag/ZnO nanocomposite immobilized on kanthal coils
Authors: Le Anh Thi , Le Thi Duy Hanh , Tuan Huynh Nguyen Anh , Koe Chee-Meng , Cheong Kuan-Yew , Tan Wai Kian , Sabar Summiyah , Hu Chenxi , Pung Swee-Yong 
Published: July 2024

Abstract
Constructing hybrid semiconductor photocatalysts and increasing the charge-carrier density are effective strategies for enhancing the photocatalytic performance of ZnO. This study elucidates the synergistic effects of electron trapping and surface plasmon resonance (SPR) on the activity of ZnO photocatalysts. Ag/ZnO nanocomposites were synthesized on Kanthal coils using a two-step method involving the immobilization of ZnO on Kanthal coils and the coupling of Ag nanoparticles. XPS and RTPL analyses verified the synergistic effects of electron trapping and SPR on the activity of the Ag/ZnO nanocomposites. The photocatalytic performance of the composite was evaluated in the degradation of rhodamine B (RhB) dye. The Ag/ZnO nanocomposite exhibited significantly enhanced removal efficiency for RhB dye (38.2–70.5% depending on the deposition time). The Ohmic contact at the Ag/ZnO heterojunction extended the lifetime of the photoinduced charge carriers, whereas the SPR facilitated the generation of more electrons for the photocatalytic reaction. However, the excessive deposition of Ag nanoparticles compromised the photocatalytic performance of the Ag/ZnO nanocomposite. This study provides valuable insights for developing efficient ZnO-based photocatalytic materials for addressing environmental challenges.
Biaxial strain modulation of NO2 adsorption on χ3 borophene: A first-principles study
Authors: Ye Li , Liang Yongchao 
Published: July 2024

Abstract
Based on first-principles calculations, the effects of applying biaxial strain to χ3 borophene and the adsorption behavior of NO2 molecule on the surface of χ3 borophene under strain are investigated. Firstly, the pristine borophene exhibits a metallic electronic structure and the thermodynamic stability of χ3 borophene is demonstrated by molecular dynamics simulations. Different adsorption sites and orientations are selected on the χ3 surface, and the optimal adsorption is found to be the S2 conformation, which has an adsorption energy of −1.589 eV. The applied biaxial strain significantly alters the electron density distribution of the χ3 borophene surface, which is predicted to be able to achieve a modification of the adsorption properties for NO2. Finally, we investigate the NO2 adsorption behavior of χ3 borophene surfaces under 1% to 5% biaxial tensile and compressive strains. Biaxial strain is found to enhance the NO2 adsorption capacity of the χ3 borophene surface, and χ3 at 3% biaxial tensile strain has the highest adsorption energy. Therefore, these results show that χ3 borophene can be a candidate material for gas sensors and theoretically guide researchers to develop more effective sensor materials for gas sensing.
High-quality ghost imaging based on undersampled natural-order Hadamard source
Authors: Liu 刘 Kang 炕 , Zhou 周 Cheng 成 , Huang 黄 Jipeng 继鹏 , Qin 秦 Hongwu 宏伍 , Liu 刘 Xuan 轩 , Li 李 Xinwei 鑫伟 , Song 宋 Lijun 立军 
Published: July 2024

Abstract
Improving the speed of ghost imaging is one of the main ways to leverage its advantages in sensitivity and imperfect spectral regions for practical applications. Because of the proportional relationship between image resolution and measurement time, when the image pixels are large, the measurement time increases, making it difficult to achieve real-time imaging. Therefore, a high-quality ghost imaging method based on undersampled natural-order Hadamard is proposed. This method uses the characteristics of the Hadamard matrix under undersampling conditions where image information can be fully obtained but overlaps, as well as deep learning to extract aliasing information from the overlapping results to obtain the true original image information. We conducted numerical simulations and experimental tests on binary and grayscale objects under undersampling conditions to demonstrate the effectiveness and scalability of this method. This method can significantly reduce the number of measurements required to obtain high-quality image information and advance application promotion.
Polarized and unpolarized off-shell
decay above the
threshold*
Authors: Hernández-Juárez A. I. , Gaitán R. , Tavares-Velasco G. 
Published: July 2024

Abstract
An analysis of the off-shell

decay width is presented for both unpolarized and polarized

gauge bosons in the scenario with the most general

vertex function, which is expressed in terms of two

-even (

and

) and one

-odd (

) anomalous couplings. The SM contributions to the

coupling up to the one-loop level are also included. Explicit analytic results for the unpolarized and polarized

square amplitudes and the four-body phase space are presented, out of which several observable quantities can be obtained straightforwardly. Regarding numerical analysis, a cross-check was performed via

, where our model was implemented with the aid of FeynRules. We then considered the most stringent bounds on anomalous complex

couplings and analyzed the effects of the polarizations of the

gauge bosons through the polarized

decay width as well as left-right and forward-backward asymmetries, which were found to be sensitive to new-physics effects. Particular focus was put on the effects of the absorptive parts of the anomalous

couplings, which have been largely overlooked up to now in LHC analyses. It was found that the studied observable quantities, particularly the left-right asymmetries, can be helpful to search for effects of

-violation in the

coupling and set bounds on the absorptive parts. For completeness, we also analyzed the case of unpolarized

gauge bosons.
Small-block frequency estimators to control step size in phase-shifting interferometry
Authors: Leroux Ian D , Eves Brian J 
Published: July 2024

Abstract
We derive an estimator for the step size in phase-shifting interferometry. Using a minimum of five samples, it avoids the occasional indeterminate results that afflict the traditional Carré step-size estimate. The estimator can be understood as a generalization of the modified-covariance frequency estimator for a real-valued sinusoid with an unknown mean. We describe its use in the NRC Gauge Block Interferometer for monitoring the motion of a phase-shifting mirror mount.
A fully-printed plasmonic nanoparticle-incorporated ZnO-based UV photodetector with very high responsivity and fast response
Authors: Debnath Subhankar , Ghosal Sirsendu , Meyyappan M , Giri P K 
Published: July 2024

Abstract
We report the development of a fully printed plasmonic Ag nanoparticle-enhanced ZnO-nanoparticle-based photodetector (PD) for the efficient detection of ultraviolet (UV) light. The contact electrodes with a gap of 200 µm are printed on a SiO2/Si substrate, and a micropattern of Ag nanoparticles (Ag NPs) is printed within the electrode gap to generate the plasmonic effect. The ZnO nanoparticle thin film is printed onto the array of Ag NPs to fabricate the plasmon-enhanced UV PD. The printed devices exhibit impressive performance with a peak responsivity of 48.8 A W−1, external quantum efficiency of 1.7 × 104%, and detectivity of 1.3 × 1013 Jones at 5 V bias. Moreover, the device shows an ultrafast photoresponse with a rise time of 24.3 µs and a fall time of 33.1 µs. Finite element method-based simulations confirm a significant field enhancement within the ZnO matrix upon incorporation of plasmonic Ag nanoparticles, explaining the increased photoresponse. The performance of the printed plasmon-enhanced UV-PD here offers a promising, simple, and inexpensive approach for the fabrication of future optoelectronic devices.
Controlling optical-cavity locking using reinforcement learning
Authors: Fazzari Edoardo , Loughlin Hudson A , Stoughton Chris 
Published: July 2024

Abstract
This study applies an effective methodology based on Reinforcement Learning to a control system. Using the Pound–Drever–Hall locking scheme, we match the wavelength of a controlled laser to the length of a Fabry-Pérot cavity such that the cavity length is an exact integer multiple of the laser wavelength. Typically, long-term drift of the cavity length and laser wavelength exceeds the dynamic range of this control if only the laser’s piezoelectric transducer is actuated, so the same error signal also controls the temperature of the laser crystal. In this work, we instead implement this feedback control grounded on Q-Learning. Our system learns in real-time, eschewing reliance on historical data, and exhibits adaptability to system variations post-training. This adaptive quality ensures continuous updates to the learning agent. This innovative approach maintains lock for eight days on average.
Association between education and walking speed: counterfactual mediation analysis in favor of a motor reserve hypothesis
Authors: Santos Félicia , Ozguler Anna , Ribet Céline , Goldberg Marcel , Zins Marie , Artaud Fanny , Elbaz Alexis 
Published: July 2024

Abstract
We quantified the extent to which the association between education and fast walking speed (FWS) is explained by 17 mediators (cardiovascular risk factors/diseases, comorbidities, health behaviors, socioprofessional characteristics, cognition), and examined whether mediators interact with education, in favor of a reserve hypothesis. Cross-sectional analyses are based on Constances (a population-based study of French adults 45-69 years). Three-meter FWS was measured using photoelectric cells. Education was categorized as lower vs higher. After multiple imputation of missing values, we used counterfactual mediation models for multiple mediators allowing for education × mediator interactions, to estimate the total effect (TE), total indirect effect (TIE), and mediated interaction (IMD) of lower education on FWS. Analyses are based on 71 222 participants (52.6% women; mean age = 57.2 years; 27.2% higher education; mean FWS = 180.2 cm/s). In joint mediation analyses, the TE of lower education was −8.19 cm/s (95% CI, −8.87 to −7.51), with a TIE of −5.76 cm/s (95% CI, −6.10 to −5.41; proportion mediated = 70.3%; 95% CI, 65.6-75.0). The IMD was negative (−2.52; 95% CI, −3.31 to −1.72); 30.8% of the TE and 43.8% of the TIE were attributable to the IMD. Several mediators explain a large part of the association between lower education and slower FWS. The detrimental effect of mediators was more pronounced in participants with lower than in those with higher education, in agreement with a reserve hypothesis.
Grandmaternal prepregnancy body mass index and infant birthweight: a mediation analysis of maternal prepregnancy body mass index
Authors: Brown Mary M , Kuhle Stefan , Smith Bruce , Allen Victoria M , Payne Jennifer , Woolcott Christy G 
Published: July 2024

Abstract
The objectives of this study were to examine the total effect of grandmaternal (G0) prepregnancy body mass index (BMI) on infant (G2) birthweight z score and to quantify the mediation role of maternal (G1) prepregnancy BMI. Data were extracted from the Nova Scotia 3G Multigenerational Cohort. The association between G0 prepregnancy BMI and G2 birthweight z score and the mediated effect by G1 prepregnancy BMI were estimated using g-computation with adjustment for confounders identified using a directed acyclic graph and accounting for intermediate confounding. A total of 20 822 G1-G2 dyads from 18 450 G0 participants were included. Relative to G0 normal weight, G0 underweight decreased mean G2 birthweight z score (−0.11; 95% CI, −0.20 to −0.030), whereas G0 overweight and obesity increased mean G2 birthweight z score (0.091 [95% CI, 0.034-0.15] and 0.22 [95% CI, 0.11-0.33], respectively). G1 prepregnancy BMI partly mediated the association, with the largest effect size observed for G0 obesity (0.11; 95% CI, 0.080-0.14). Estimates of the direct effect were close to the null. In conclusion, grandmaternal prepregnancy BMI was associated with infant birthweight z score. Maternal prepregnancy BMI partly mediated the association, suggesting that factors related to BMI may play an important role in the transmission of weight across the maternal line.
The smallest angiosperm genomes may be the price for effective traps of bladderworts
Authors: Zedek František , Šmerda Jakub , Halasová Aneta , Adamec Lubomír , Veleba Adam , Plačková Klára , Bureš Petr 
Published: July 2024

Abstract

Background
Species of the carnivorous family Lentibulariaceae exhibit the smallest genomes in flowering plants. We explored the hypothesis that their minute genomes result from the unique mitochondrial cytochrome c oxidase (COX) mutation. The mutation may boost mitochondrial efficiency, which is especially useful for suction-bladder traps of Utricularia, but also increase DNA-damaging reactive oxygen species, leading to genome shrinkage through deletion-biased DNA repair. We aimed to explore the impact of this mutation on genome size, providing insights into genetic mutation roles in plant genome evolution under environmental pressures.

Methods
We compiled and measured genome and mean chromosome sizes for 127 and 67 species, respectively, representing all three genera (Genlisea, Pinguicula and Utricularia) of Lentibulariaceae. We also isolated and analysed COX sequences to detect the mutation. Through phylogenetic regressions and Ornstein–Uhlenbeck models of trait evolution, we assessed the impact of the COX mutation on the genome and chromosome sizes across the family.

Results
Our findings reveal significant correlations between the COX mutation and smaller genome and chromosome sizes. Specifically, species carrying the ancestral COX sequence exhibited larger genomes and chromosomes than those with the novel mutation. This evidence supports the notion that the COX mutation contributes to genome downsizing, with statistical analyses confirming a directional evolution towards smaller genomes in species harbouring these mutations.

Conclusions
Our study confirms that the COX mutation in Lentibulariaceae is associated with genome downsizing, probably driven by increased reactive oxygen species production and subsequent DNA damage requiring deletion-biased repair mechanisms. While boosting mitochondrial energy output, this genetic mutation compromises genome integrity and may potentially affect recombination rates, illustrating a complex trade-off between evolutionary advantages and disadvantages. Our results highlight the intricate processes by which genetic mutations and environmental pressures shape genome size evolution in carnivorous plants.
Identifying pleiotropic genes via the composite test amidst the complexity of polygenic traits
Authors: Lai En-Yu , Huang Yen-Tsung 
Published: July 2024

Abstract
Identifying the causal relationship between genotype and phenotype is essential to expanding our understanding of the gene regulatory network spanning the molecular level to perceptible traits. A pleiotropic gene can act as a central hub in the network, influencing multiple outcomes. Identifying such a gene involves testing under a composite null hypothesis where the gene is associated with, at most, one trait. Traditional methods such as meta-analyses of top-hit $P$-values and sequential testing of multiple traits have been proposed, but these methods fail to consider the background of genome-wide signals. Since Huang’s composite test produces uniformly distributed $P$-values for genome-wide variants under the composite null, we propose a gene-level pleiotropy test that entails combining the aforementioned method with the aggregated Cauchy association test. A polygenic trait involves multiple genes with different functions to co-regulate mechanisms. We show that polygenicity should be considered when identifying pleiotropic genes; otherwise, the associations polygenic traits initiate will give rise to false positives. In this study, we constructed gene–trait functional modules using the results of the proposed pleiotropy tests. Our analysis suite was implemented as an R package PGCtest. We demonstrated the proposed method with an application study of the Taiwan Biobank database and identified functional modules comprising specific genes and their co-regulated traits.