bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual-contrast photon-counting micro-CT using iodine and a novel bismuth-based contrast agent
Authors: Amato Carlo , Susenburger Markus , Lehr Samuel , Kuntz Jan , Gehrke Nicole , Franke Danielle , Thüring Thomas , Briel Andreas , Brönnimann Christian , Kachelrieß Marc , Sawall Stefan 
Published: June 2023

Abstract

Objectives. To characterize for the first time in vivo a novel bismuth-based nanoparticular contrast agent developed for preclinical applications. Then, to design and test in vivo a multi-contrast protocol for functional cardiac imaging using the new bismuth nanoparticles and a well-established iodine-based contrast agent. Approach. A micro-computed tomography scanner was assembled and equipped with a photon-counting detector. Five mice were administered with the bismuth-based contrast agent and systematically scanned over 5 h to quantify the contrast enhancement in relevant organs of interest. Subsequently, the multi-contrast agent protocol was tested on three mice. Material decomposition was performed on the acquired spectral data to quantify the concentration of bismuth and iodine in multiple structures, e.g. the myocardium and vasculature. Main results. In the vasculature, the bismuth agent provides a peak enhancement of 1100 HU and a half-life of about 260 min. After the injection, it accumulates in the liver, spleen and intestinal wall reaching a CT value of 440 HU about 5 h post injection. Phantom measurements showed that the bismuth provides more contrast enhancement than iodine for a variety of tube voltages. The multi-contrast protocol for cardiac imaging successfully allowed the simultaneous decomposition of the vasculature, the brown adipose tissue and the myocardium. Significance. The new bismuth-based contrast agent was proven to have a long circulation time suitable for preclinical applications and to provide more contrast than iodine agents. The proposed multi-contrast protocol resulted in a new tool for cardiac functional imaging. Furthermore, thanks to the contrast enhancement provided in the intestinal wall, the novel contrast agent may be used to develop further multi contrast agent protocols for abdominal and oncological imaging.
Hydrogenated amorphous silicon high flux x-ray detectors for synchrotron microbeam radiation therapy
Authors: Large Matthew J , Bizzarri Marco , Calcagnile Lucio , Caprai Mirco , Caricato Anna Paola , Catalano Roberto , Cirrone Giuseppe A P , Croci Tommaso , Cuttone Giacomo , Dunand Sylvain , Fabi Michele , Frontini Luca , Gianfelici Benedetta , Grimani Catia , Ionica Maria , Kanxheri Keida , Lerch Michael L F , Liberali Valentino , Martino Maurizio , Maruccio Giuseppe , Mazza Giovanni , Menichelli Mauro , Monteduro Anna Grazia , Moscatelli Francesco , Morozzi Arianna , Pallotta Stefania , Papi Andrea , Passeri Daniele , Pedio Maddalena , Petringa Giada , Peverini Francesca , Piccolo Lorenzo , Placidi Pisana , Quarta Gianluca , Rizzato Silvia , Rossi Alessandro , Rossi Giulia , de Rover Vincent , Sabbatini Federico , Servoli Leonello , Stabile Alberto , Talamonti Cinzia , Tosti Luca , Villani Mattia , Wheadon Richard J , Wyrsch Nicolas , Zema Nicola , Petasecca Marco 
Published: June 2023

Abstract

Objective. Microbeam radiation therapy (MRT) is an alternative emerging radiotherapy treatment modality which has demonstrated effective radioresistant tumour control while sparing surrounding healthy tissue in preclinical trials. This apparent selectivity is achieved through MRT combining ultra-high dose rates with micron-scale spatial fractionation of the delivered x-ray treatment field. Quality assurance dosimetry for MRT must therefore overcome a significant challenge, as detectors require both a high dynamic range and a high spatial resolution to perform accurately. Approach. In this work, a series of radiation hard a-Si:H diodes, with different thicknesses and carrier selective contact configurations, have been characterised for x-ray dosimetry and real-time beam monitoring applications in extremely high flux beamlines utilised for MRT at the Australian Synchrotron. Results. These devices displayed superior radiation hardness under constant high dose-rate irradiations on the order of 6000 Gy s−1, with a variation in response of 10% over a delivered dose range of approximately 600 kGy. Dose linearity of each detector to x-rays with a peak energy of 117 keV is reported, with sensitivities ranging from (2.74 ± 0.02) nC/Gy to (4.96 ± 0.02) nC/Gy. For detectors with 0.8 μm thick active a-Si:H layer, their operation in an edge-on orientation allows for the reconstruction of micron-size beam profiles (microbeams). The microbeams, with a nominal full-width-half-max of 50 μm and a peak-to-peak separation of 400 μm, were reconstructed with extreme accuracy. The full-width-half-max was observed as 55 ± 1 μm. Evaluation of the peak-to-valley dose ratio and dose-rate dependence of the devices, as well as an x-ray induced charge (XBIC) map of a single pixel is also reported. Significance. These devices based on novel a-Si:H technology possess a unique combination of accurate dosimetric performance and radiation resistance, making them an ideal candidate for x-ray dosimetry in high dose-rate environments such as FLASH and MRT.
An AI-based universal phantom analysis method based on XML-SVG wireframes with novel functional object identifiers
Authors: Sakaamini Ahmad , Van Slyke Alexander , Partouche Julien , Wu Tianming , Wiersma Rodney D 
Published: June 2023

Abstract

Objective. Quality assurance (QA) testing must be performed at regular intervals to ensure that medical devices are operating within designed specifications. Numerous QA phantoms and software packages have been developed to facilitate measurements of machine performance. However, due to the hard-coded nature of geometric phantom definition in analysis software, users are typically limited to the use of a small subset of compatible QA phantoms. In this work, we present a novel AI-based universal Phantom (UniPhan) algorithm that is not phantom specific and can be easily adapted to any pre-existing image-based QA phantom. Approach. Extensible Markup Language Scalable Vector Graphics (XML-SVG) was modified to include several new tags describing the function of embedded phantom objects for use in QA analysis. Functional tags include contrast and density plugs, spatial linearity markers, resolution bars and edges, uniformity regions, and light-radiation field coincidence areas. Machine learning was used to develop an image classification model for automatic phantom type detection. After AI phantom identification, UniPhan imported the corresponding XML-SVG wireframe, registered it to the image taken during the QA process, performed analysis on the functional tags, and exported results for comparison to expected device specifications. Analysis results were compared to those generated by manual image analysis. Main results. XML-SVG wireframes were generated for several commercial phantoms including ones specific to CT, CBCT, kV planar imaging, and MV imaging. Several functional objects were developed and assigned to the graphical elements of the phantoms. The AI classification model was tested for training and validation accuracy and loss, along with phantom type prediction accuracy and speed. The results reported training and validation accuracies of 99%, phantom type prediction confidence scores of around 100%, and prediction speeds of around 0.1 s. Compared to manual image analysis, Uniphan results were consistent across all metrics including contrast-to-noise ratio, modulation-transfer function, HU accuracy, and uniformity. Significance. The UniPhan method can identify phantom type and use its corresponding wireframe to perform QA analysis. As these wireframes can be generated in a variety of ways this represents an accessible automated method of analyzing image-based QA phantoms that is flexible in scope and implementation.
Study of particle acceleration by Laguerre–Gaussian ultra intense laser plasma interactions
Authors: Culfa O , Sagir S , Satilmis I 
Published: June 2023

Abstract
In this work, simulations of multi-petawatt lasers in the range of ∼0.2 PW–∼100 PW with varying Laguerre–Gaussian (LG) azimuthal modes as well as linearly polarized (LP) and circularly polarized (CP) laser beams striking near critical density targets were studied by using three-dimensional particle in cell (PIC) codes. Particle acceleration mechanisms have a dependence on laser polarization and it affects the energy gained by the particles. It is known that laser pulses can be polarized helically by applying the LG distribution function to the fundamental Gaussian laser profile. In this study, differently polarized laser beams with varying powers were employed to study laser driven particle acceleration and compares accelerated charged particles’ energy spectra and angular distribution. It is seen that LG laser beams can accelerate higher energetic particles due to higher conversion efficiency compared to LP and CP laser beams. It is also seen that LG laser beams can collimate ions with a narrower spread compared to LP and CP beams. Furthermore, ions can have a smaller divergence angle with increasing azimuthal mode index when the laser is LG polarized. We also studied the energy deposition of these particles in a water cell obtained by the PIC codes for different laser parameters by using Geant4 Monte Carlo simulations which suggests that LG laser beam can be useful for the future hadron therapy applications.
Efficient modeling of electron kinetics under influence of externally applied electric field in magnetized weakly ionized plasma
Authors: Janalizadeh Reza , Pervez Zaid , Pasko Victor P 
Published: June 2023

Abstract
We present a theory based on the conventional two-term (i.e. Lorentzian) approximation to the exact solution of the Boltzmann equation in non-magnetized weakly ionized plasma to efficiently obtain the electron rate and transport coefficients in a magnetized plasma for an arbitrary magnitude and direction of applied electric field

E
⃗

and magnetic field

B
⃗

. The proposed transcendental method does not require the two-term solution of the Boltzmann equation in magnetized plasma, based on which the transport parameters vary as a function of the reduced electric field

E

/

N

, reduced electron cyclotron frequency

ω

c
e

/

N

, and angle

∠

E
⃗

,

B
⃗

between

E
⃗

and

B
⃗

vectors, where N is the density of neutrals. Comparisons between the coefficients derived from BOLSIG+’s solution (obtained via the two-term expansion when

B
⃗

≠
0

) and coefficients of the presented method are illustrated for air, a mixture of molecular hydrogen (H2) and helium (He) representing the giant gas planets of the Solar System, and pure carbon dioxide (CO2). The new approach may be used in the modeling of magnetized plasma encountered in the context of transient luminous events, e.g. sprite streamers in the atmosphere of Earth and Jupiter, in modeling the propagation of lightning’s electromagnetic pulses in Earth’s ionosphere, and in various laboratory and industrial applications of nonthermal plasmas.
Coupled electro-aeroelastic energy harvester model based on piezoelectric transducers, VIV-galloping interaction and nonlinear switching circuits
Authors: Priore Emiliano Del , Romano Giovanni Paolo , Lampani Luca 
Published: June 2023

Abstract
Miniaturization, multi-functionality, and low power consumption are key features in the development of electronic devices today. These characteristics open up the possibility for the development of small, self-powered systems. Piezoelectric materials have emerged as a promising solution due to their ability to convert mechanical energy into electrical energy from the surrounding environment, such as wind. In this research work, we investigate an aeroelastic piezoelectric energy harvester based on the interaction between vortex-induced vibrations and galloping. The device, a bimorph cantilevered beam with a square-section bluff body attached to its tip, produces mechanical oscillations that are extracted by various electrical circuits, including a nonlinear switching interface. A numerical model, implemented in a Simulink environment, is developed to solve the coupled electro-aeroelastic problem for each electrical interface. The results are compared to experimental data collected from wind tunnel tests conducted at various wind velocities and load resistances, and a satisfactory correlation is observed. The validated model is finally used to carry out a parametric analysis aimed at optimizing the performance of the harvester in a low wind speed range. This investigation could contribute to a better understanding of an aeroelastic harvesting system and potentially assist in the optimization of design parameters and electrical interfaces for specific applications.
Scaling superconducting quantum chip with highly integratable quantum building blocks
Authors: Cai Xiao , Zhou Boyi , Wu Yanfu , Li Shuming , Dong Yuqian , Feng Jiagui , Xiong Kanglin 
Published: June 2023

Abstract
Designing and fabricating large-scale superconducting quantum chips with increasing number of qubits is a pressing challenge for the quantum computing. Here, we propose a three-dimensional stacked chip architecture comprised with quantum building blocks. In which, two primary types of blocks are the qubit block and the coupling block. They are designed as functional parts that can be utilized within the same footprint across multiple levels of the chip stack in the vertical direction. Common technological problems, such as the sensitivity of capacitors and coupling strengths to fabrication parameters, and dielectric losses from interfaces, can be addressed at the intra-block or block level efficiently. Once a library of standard blocks is designed and verified, they can be selected and arranged into arrays on chips at the placing stage of the design flow for specific quantum applications. Such chip structure and design protocol will reduce the design difficulty, and promote the reuse of standard blocks, thus paving the way for chips for noisy intermediate-scale quantum computing and quantum error correction.
Unification of the four forces in the Spin(11,1) geometric algebra
Authors: Hamilton Andrew J S , McMaken Tyler 
Published: June 2023

Abstract
SO(10), or equivalently its covering group Spin(10), is a well-known promising grand unified group that contains the standard-model group. The spinors of the group Spin(N) of rotations in N spacetime dimensions are indexed by a bitcode with [N/2] bits. Fermions in Spin(10) are described by five bits yzrgb, consisting of two weak bits y and z, and three colour bits r, g, b. If a sixth bit t is added, necessary to accommodate a time dimension, then the enlarged Spin(11, 1) algebra contains the standard-model and Dirac algebras as commuting subalgebras, unifying the four forces. The minimal symmetry breaking chain that breaks Spin(11, 1) to the standard model is unique, proceeding via the Pati-Salam group. The minimal Higgs sector is similarly unique, consisting of the dimension 66 adjoint representation of Spin(11, 1); in effect, the scalar Higgs sector matches the vector gauge sector. Although the unified algebra is that of Spin(11, 1), the persistence of the electroweak Higgs field after grand symmetry breaking suggests that the gauge group before grand symmetry breaking is Spin(10, 1), not the full group Spin(11, 1). The running of coupling parameters predicts that the standard model should unify to the Pati-Salam group Spin(4)
w
× Spin(6)
c
at 1012 GeV, and thence to Spin(10, 1) at 1015 GeV. The grand Higgs field breaks t-symmetry, can drive cosmological inflation, and generates a large Majorana mass for the right-handed neutrino by flipping its t-bit. The electroweak Higgs field breaks y-symmetry, and generates masses for fermions by flipping their y-bit.
Twin-image-free compressive holography with autofocusing from single subsampled hologram
Authors: Zhang Cheng , Zhou Jiaxuan , Wu Feng , Wei Sui 
Published: June 2023

Abstract
Compressive-sensing-based twin-image-free approach is only capable to achieve twin-image-free reconstruction under 2D-2D imaging model with the full-sampling condition. In this paper, a compressive holography approach with autofocusing from a single-shot subsampled hologram is proposed. On the one hand, a subsampling mechanism is introduced to establish a subsampled compressive holographic imaging model; On the other hand, an eigenvalues-based autofocusing algorithm is combined with compressive-sensing to achieve autofocus reconstruction under subsampling condition in compressive holography. In addition, a multi-scale search algorithm is proposed to improve the accuracy of autofocus. Numerical experiments verify the feasibility of our proposed approach in terms of precisely autofocusing and twin-image-free reconstruction from single-shot subsampled holograms.
Improved diffractive-imaging based image encryption scheme in 3D space
Authors: Shan Mingguang , Xu Yanjun , Zhong Zhi , Liu Bin , Yu Lei , Xie Yongqiang , Liu Lei 
Published: June 2023

Abstract
In this paper, we present an improved diffractive-imaging-based image encryption scheme in 3D space. In this cryptosystem, the plaintext is divided into several sub-images by binary amplitude masks and then diffused into 3D space at different axial positions for encryption, which confuses the relation between the plaintext and the ciphertext to make the chosen-plaintext attack no longer work. For the decryption, we develop a modified iterative retrieval algorithm to retrieve a decrypted image with high quality. Additionally, this cryptosystem obtains higher security without increasing the amount of the ciphertext. Compared with previous diffractive-imaging-based image encryption schemes, the key space is enlarged so greatly that this cryptosystem can resist the brute force attack. Furthermore, this scheme can significantly reduce the computation and retrieve a decrypted image with high-quality.
Tunable nonlinear absorption and optical limiting behavior of NaBi(MoxW1−xO4)2 single crystals with ratio of Molybdenum/Tungsten
Authors: Pepe Yasemin , Yildiz Elif Akhuseyin , Isik Mehmet , Karatay Ahmet , Gasanly Nizami , Elmali Ayhan 
Published: June 2023

Abstract
The compositional effect of Mo/W ratio on linear, nonlinear absorption and optical limiting behavior of the NaBi(MoxW1−xO4)2 single crystals grown by Czochralski technique was investigated. X-ray diffraction patterns of the studied crystals presented well-defined peaks associated with the tetragonal crystalline structure. The nonlinear absorption performance and optical limiting threshold were determined using an open-aperture Z-scan technique. A theoretical model including one photon absorption (OPA), two photon absorption (TPA) and free carrier absorption was used to determine the nonlinear absorption parameters. All of the results showed that defect states, which strongly affect nonlinear absorption (NA) and optical limiting behaviors, can be tuned with the Mo/W ratio, enabling NaBi(MoxW1−xO4)2 single crystals to be used in desired optoelectronic applications. Linear optical absorption analysis revealed that bandgap energy and defect states can be tuned by changing the Mo/W ratio in the crystal structure. The obtained results showed that all the studied crystals had NA behavior and the nonlinear absorption coefficient decreased with increasing Mo/W ratio. Sequential TPA is the main NA mechanism for these crystals due to the fact that the incident light energy is lower than the bandgap energies and the existence of the real intermediate state around 2.32 eV.
Band gap characteristics of multi-functional lattice metamaterials with adjustable thermal expansion and Poisson's ratio
Authors: Liu Hongliang , Jiang Yihuang , Xu Weikai , Wang Wei , Yu Xiaoming 
Published: June 2023

Abstract
The current development of science and technology has put increased demands on the versatility of metamaterials. In this paper, the band gap characteristics of a lattice metamaterial that can simultaneously modulate thermal expansion and Poisson’s ratio are studied, the dispersion characteristics of elastic waves propagating in periodic lattice metamaterials are analyzed, and the effects of different structures and parameters on the band gap are discussed. The results indicate that the configuration has excellent band gap properties while satisfying the tunable coefficient thermal expansion (CTE)and Poisson’s ratio functions. Through reasonable material selection and shape design, it is expected to achieve a multi-objective win-win for specific thermal expansion properties, Poisson’s ratio, and band gap design, resulting in better tunability and versatility of the metamaterial.
Sensing strategy based on random slot semiconductor laser
Authors: Jia Xiaoqin , Wang Yufei , Liu Guangqiang , Zhou Xuyan , Zhang Jianxin , Dong Fengxin , Gong Kai , Zhang Run 
Published: June 2023

Abstract
A photonic sensor based on a random slot surface-emitting semiconductor laser is theoretically demonstrated by utilizing multi-order diffraction. The results show that the variation of far-field local speckles at single wavelength lasing can be utilized to confirm the refractive index of the substances and the flow velocity of erythrocytes in capillaries. The similarity of the intensity contrast is the other protocol to measure the flow velocity of erythrocytes. Additionally, the similarity of the spectral contrast at multiple wavelengths lasing can be used to determine the concentration of erythrocytes in capillaries. The random slot semiconductor laser may provide a new and flexible platform for versatile active sensing.
Estimating cross-field particle transport at the outer midplane of TCV by tracking filaments with machine learning
Authors: Han W. , Offeddu N. , Golfinopoulos T. , Theiler C. , Terry J.L. , Wüthrich C. , Galassi D. , Colandrea C. , Marmar E.S. 
Published: June 2023

Abstract
Cross-field transport of particles in the boundary region of magnetically confined fusion plasmas is dominated by turbulence. Blobs, intermittent turbulent structures with large amplitude and a filamentary shape appearing in the scrape-off layer (SOL), are known from theoretical and experimental studies to be the main contributor to the cross-field particle transport. The dynamics of blobs differs depending on various plasma conditions, including triangularity (δ). In this work, we analyze triangularity dependence of the cross-field particle transport at the outer midplane of plasmas with

δ
=
+
0.38

, +0.15, −0.14, and −0.26 on the Tokamak à Configuration Variable, using our novel machine learning (ML) blob-tracking approach applied to gas puff imaging data. The cross-field particle flux determined in this way is of the same order as the overall transport inferred from KN1D, GBS, and SOLPS-ITER simulations, suggesting that the blobs identified by the ML blob-tracking account for most of the cross-field particle transport in the SOL. Also, the ML blob-tracking and KN1D show a decrease in the cross-field particle transport as δ becomes more negative. The blob-by-blob analysis of the result from the tracking reveals that the decrease of cross-field particle transport with decreasing δ is accompanied by a decrease in the number of blobs in a fixed time, which tend to have larger area and lower radial speed. Also, the blobs in these plasmas are in the connected sheath regime, and show a velocity scaling consistent with the two-region model.