bluuebunny/crossref_metadata_2025_split huggingface dataset:
E-TEST: a compact low-frequency isolator for a large cryogenic mirror
Authors: Sider A , Di Fronzo C , Amez-Droz L , Amorosi A , Badaracco F , Baer P , Bertolini A , Bruno G , Cebeci P , Collette C , Ebert J , Erben B , Esteves R , Ferreira E , Gatti A , Giesberts M , Hebbeker T , van Heijningen J V , Hennig J-S , Hennig M , Hild S , Hoefer M , Hoffmann H-D , Jacques L , Jamshidi R , Joppe R , Kuhlbusch T-J , Lakkis M H , Lenaerts C , Locquet J-P , Loicq J , Le Van B Long , Loosen P , Nesladek M , Reiter M , Stahl A , Steinlechner J , Steinlechner S , Tavernier F , Teloi M , Vilaboa Pérez J , Zeoli M 
Published: June 2023

AbstractTo achieve the expected level of sensitivity of third-generation gravitational-wave (GW) observatories, more accurate and sensitive instruments than those of the second generation must be used to reduce all sources of noises. Amongst them, one of the most relevant is seismic noise, which will require the development of a better isolation system, especially at low frequencies (below 10 Hz), the operation of large cryogenic silicon mirrors, and the improvement of optical wavelength readouts. In this framework, this article presents the activities of the E-TEST (Einstein Telescope Euregio Meuse-Rhine Site & Technology) to develop and test new key technologies for the next generation of GW observatories. A compact isolator system for a large silicon mirror (100 kg) at low frequency (<10 Hz) is proposed. The design of the isolator allows the overall height of the isolation system to be significantly compact and also suppresses seismic noise at low frequencies. To minimize the effect of thermal noise, the isolation system is provided with a 100 kg silicon mirror which is suspended in a vacuum chamber at cryogenic temperature (25–40 K). To achieve this temperature without inducing vibrations to the mirror, a radiation-based cooling strategy is employed. In addition, cryogenic sensors and electronics are being developed as part of the E-TEST to detect vibrational motion in the penultimate cryogenic stage. Since the commonly used silicon material is not transparent below the wavelengths typically used in the 1µm range for GW detectors, new optical components and lasers must be developed in the range above 1500 nm to reduce absorption and scattering losses. Therefore, solid-state and fiber lasers with a wavelength of 2090 nm, matching high-efficiency photodiodes, and low-noise crystalline coatings are being developed. Accordingly, the key technologies provided by E-TEST serve crucially to reduce the limitations of the current generation of GW observatories and to determine the technical design for the next generation.
A new approach and code for spinning black holes in modified gravity
Authors: Fernandes Pedro G S , Mulryne David J 
Published: June 2023

AbstractWe discuss and implement a spectral method approach to computing stationary and axisymmetric black hole solutions and their properties in modified theories of gravity. The resulting code is written in theJulialanguage and is transparent and easily adapted to new settings. We test the code on both general relativity and on Einstein-scalar-Gauss–Bonnet gravity. It is accurate and fast, converging on a spinning solution in these theories with tiny errors (in most cases) in a matter of seconds.
Post-Newtonian-accurate pulsar timing array signals induced by inspiralling eccentric binaries: accuracy, computational cost, and single-pulsar search
Authors: Susobhanan Abhimanyu 
Published: June 2023

Abstract
Pulsar Timing Array (PTA) experiments are expected to be sensitive to gravitational waves (GWs) emitted by individual supermassive black hole binaries (SMBHBs) inspiraling along eccentric orbits. We compare the computational cost of different methods of computing the PTA signals induced by relativistic eccentric SMBHBs, namely approximate analytic expressions, Fourier series expansion, post-circular expansion, and numerical integration. We show that the fastest method for evaluating PTA signals is by using the approximate analytic expressions, which provides up to ∼50 times improvement in computational speed over the alternative methods. We investigate the accuracy of the approximate analytic expressions by employing a mismatch metric valid for PTA signals. We show that this method is accurate within the region of the binary parameter space that is of interest to PTA experiments. We introduce a spline-based method to further accelerate the PTA signal evaluations for narrowband PTA datasets. The efficient methods for computing the eccentric SMBHB-induced PTA signals were implemented in the GWecc.jl package and can be readily accessed from the popular ENTERPRISE package to search for such signals in PTA datasets. Further, we simplify the eccentric SMBHB PTA signal expression for the case of a single-pulsar search and demonstrate our computationally efficient methods by performing a single-pulsar search in the 12.5 year NANOGrav narrowband dataset of PSR J1909–3744 using the simplified expression. These results will be crucial for searching for eccentric SMBHBs in large PTA datasets.
Influence of parasitic optical losses on the performance of perovskite solar cells
Authors: Peng Yinsheng , Wang Shurong , Liu Zuming , Zhou Zhineng , Zhou Shouli , Yao Minghai 
Published: June 2023

Abstract
Parasitic optical losses, including free-carrier absorption and absorption from the rear mirror, could significantly affect the performance of solar cells. Although estimates of their influence have been made in the past, they have not previously been incorporated into the absorptivity of semiconductor materials and their influence on the performance of perovskite solar cells studied quantitatively. This paper numerically investigates the impact of both typical kinds of parasitic optical losses on the performance of perovskite solar cells utilizing the detailed balance model. It is found that the free carrier absorption loss has nearly no influence on the performance of perovskite solar cells, but parasitic absorption at the rear mirror can significantly affect the performance of solar cells. For thin film perovskite solar cells, parasitic absorption significantly affects the short circuit current, open circuit voltage and power conversion efficiency (PCE), but for thick solar cells, the short circuit current is nearly independent of the parasitic absorption; it seriously affects the open circuit voltage and PCE.
Order-degree-modulated ferroic response and an unconventional electrocaloric effect in B-site complex systems: a case study in Pb[(Yb1/2Nb1/2)0.84(Mg1/3Nb2/3)0.16]O3 ceramic
Authors: Li Feng , Long Mingsheng , Lou Xiaojie , Wang Chunchang , Shan Lei 
Published: June 2023

Abstract
The order-degree-modulated ferroic response and electrocaloric effect (ECE) in Pb(B1,B2)O3-type B-site complex antiferroelectrics (AFEs) are explored in this work. The results show that local/phase structure and dielectric/ferroic properties are strikingly dependent on the degree of order (high, intermediate and low for samples S1, S2 and S3, respectively). A decrease in the content of the AFE orthorhombic phase and an increase in the weakly polar disorder phase is observed from S1 to S3, accompanied by an enhanced relaxation behavior with a smearing of the AFE-to-paraelectric phase transition. Ferroic and EC responses in the three samples present distinct features. Antiferroelectricity wakes-up significantly in sample S1, which boosts the ECE to ∼0.95 K and is almost three times that of S3 (∼0.23 K). An abnormal ECE [negative ECE with a hop–hop character and asymmetrical electrocaloric (EC) response] is unexpectedly found in sample S1. The underlying mechanism is unveiled by dipolar relaxation and phenomenology analysis, which states that the AFE coupling strength dominates the EC performance in this AFE. This work not only presents a refreshing method for order-degree regulation of the ECE in B-site complex AFEs, but also clarifies the possibility that AFEs with robust dipolar coupling strength have an unconventional ECE.
Study of the annealing effect in optical properties for phosphorus-doped a-Si
x
C1−
x
:H films deposited by PECVD
Authors: Valencia-Grisales D F , Reyes-Betanzo C 
Published: June 2023

Abstract
The optical properties of phosphorus-doped hydrogenated amorphous silicon carbide (P-doped a-Si
x
C1−x
:H) thin films are studied. Films were deposited by plasma-enhanced chemical vapor deposition at 110 kHz of frequency and pressure of 1.5 Torr, with silane (SiH4) and methane (CH4) as precursor gases. Hydrogen (H2) and phosphine (PH3) were used as diluent and dopant gases, respectively. The impact of the gases flow rate and thermal annealing on the optical properties is evaluated. A concordance is observed between the atomic content of Si, C, and P in films, determined by Energy Dispersive X-ray Spectroscopy, as gases flow rate increases. The composition of the films is established by identifying the vibrational bonding modes using Fourier transform infrared spectroscopy measurements. Si−H, Si−C, and C−H bonds were identified and their density was obtained. Characterization with UV–Vis spectroscopy shows that the optical band gap (E
gopt), oscillation energy (Eo
), Urbach energy (EU
), and iso-absorption energy (E
04) increase with the doping level but decrease with the annealing treatment. However, values of dispersion energy (Ed
), dielectric constant (ϵ) and the refractive index (n) generally become smaller as the phosphorus and carbon content grows, but with a tendency to fall during the annealing. The refractive index by UV–Vis is compared with measurements made with ellipsometry, resulting in a similarity between both techniques. High values of E
gopt obtained in P-doped a-Si
x
C1−x
:H films can be related to better values of the temperature coefficient of resistance for flow sensor applications.
Fermi surface and light quasi particles in hourglass nodal chain metal β-ReO2
Authors: Hirai Daigorou , Anbai Takahito , Konoike Takako , Uji Shinya , Hattori Yuya , Terashima Taichi , Ishikawa Hajime , Kindo Koichi , Katayama Naoyuki , Oguchi Tamio , Hiroi Zenji 
Published: June 2023

Abstract
Quantum oscillations (QOs) in magnetic torque and electrical resistivity were measured to investigate the electronic structure of β-ReO2, a candidate hourglass nodal chain (NC) metal (Dirac loop chain metal). All the de Haas–van Alphen oscillation branches measured at 30 mK in magnetic fields of up to 17.5 T were consistent with first-principles calculations predicting four Fermi surfaces (FSs). The small-electron FS of the four FSs exhibited a very small cyclotron mass, 0.059 times that of the free electrons, which is likely related to the linear dispersion of the energy band. The consistency between the QO results and band calculations indicates the presence of the hourglass NC predicted for β-ReO2 in the vicinity of the Fermi energy.
Calibration of high accuracy accelerometers for ESA missions BepiColombo and JUICE at INRIM
Authors: Astrua Milena , Pisani Marco , Santiano Marco , Audrito Emanuele 
Published: June 2023

Abstract
High sensitive triaxial accelerometers are used in several space missions to measure the non-gravitational accelerations acting on the spacecraft. Among these, the capacitive accelerometers developed for ESA missions Jupiter Icy moons Explorer (JUICE) and BepiColombo were designed to measure accelerations of the order of 3 · 10−6 m s−2 with an accuracy level of 300 ppm in the frequency range (3 · 10−5–0.1) Hz. Despite the signal to be measured is of the same order of magnitude of the seismic noise on the earth, an accurate on-ground calibration is needed. The facility set-up at INRIM to this purpose is based on a simple principle: the base of the accelerometer is dynamically tilted by an angle α so that the sensor undergoes a component of the gravitational acceleration g proportional to angle α. In practice, several issues have to be addressed by the calibration facility, such as the seismic noise limiting the signal-to-noise ratio, the generation and the accurate measurement of the tilt angle. Furthermore, the calibration was performed taking into account different on-flight conditions such as different operating temperatures and possible deformation of the accelerometers during the launch. The experimental set-up and the calibration procedure are described in the paper. The measurement results and the uncertainty budget show that a relative accuracy of 240 ppm has been achieved.
Experiments and modeling of fluctuating frictional force of pipeline inspection gauges
Authors: Zhang Zhongchao , Li Yiming , Song Guiqiu 
Published: June 2023

Abstract
At present, pipeline inspection gauge (PIG) is the main means to ensure the reliability of oil and gas transportation pipelines. Due to the unstable friction between the PIG and the pipeline, the failure and blockage of the PIG often occurs. In this paper, the theoretical modeling and experimental measurement of fluctuating friction on PIG are studied. Firstly, considering the coupling relationship between cylindrical shell and conical shell, the contact radial force model between PIG and pipeline is derived. Based on which, the nonlinear frictional model of PIG is proposed, and the parameters are measured by several experiments. Then an experimental platform is developed to measure the fluctuating friction force of PIG in actual operation, and verify the accuracy of the proposed model. The motion characteristic analysis and dynamics research are carried out, and the PIG creeping phenomenon caused by fluctuating friction is explained. Finally, based on the proposed nonlinear friction model, the influence of parameters is analyzed. The conclusions based on the proposed model and the experiments results can provide technical supports for practical engineering application.
Effect of interface and matrix strength on transverse tensile strength of unidirectional CFRP composite
Authors: Bu Pengfei , Ruan Wenjun , Liu Jiangong 
Published: June 2023

Abstract
To illustrate the effect of interface and matrix on the transverse mechanical properties of unidirectional carbon fiber reinforced polymer (UD-CFRP) composites, a calculation method for the transverse tensile strength of UD-CFRP considering the interface cracking process was proposed. The effect of interface crack on the composite stress field was considered based on the representative volume element model with a crack interface, and the crack propagation behavior of interface was simulated by the Benzeggagh-Kenane criterion. The transverse tensile strength of unidirectional T300/BSL914C composites was studied using the theoretical method and finite element (FE) model with random fiber distribution. The theoretical results agreed well with the FE results and the relationships between composite strength, interface strength and matrix strength were provided by the theoretical method. The results show that the interface could be divided into three types according to the strength ratio of interface and matrix, including weakest interface, weak interface, and strong interface. When the interface belongs to the weakest or strong interface, the transverse tensile strength is unaffected by the interface strength and it increases linearly with the increase of matrix strength. When the interface belongs to the weak interface, the transverse tensile strength increases linearly with the increase of interface strength and it is unaffected by matrix strength.
Acoustic radiation force for analyzing the mechanical stress in ultrasound neuromodulation
Authors: Kim Young Hun , Lee Chang Hoon , Firouzi Kamyar , Park Beom Hoon , Pyun Joo Young , Kim Jeong Nyeon , Park Kwan Kyu , Khuri-Yakub Butrus T 
Published: June 2023

Abstract

Objective. Although recent studies have shown that mechanical stress plays an important role in ultrasound neuromodulation, the magnitude and distribution of the mechanical stress generated in tissues by focused ultrasound transducers have not been adequately examined. Various acoustic radiation force (ARF) equations used in previous studies have been evaluated based on the tissue displacement results and are suitable for estimating the displacement. However, it is unclear whether mechanical stress can be accurately determined. This study evaluates the mechanical stress predicted by various AFR equations and suggests the optimal equation for estimating the mechanical stress in the brain tissue. Approach. In this paper, brain tissue responses are compared through numerical finite element simulations by applying the three most used ARF equations—Reynolds stress force ((RSF)), momentum flux density tensor force, and attenuation force. Three ARF fields obtained from the same pressure field were applied to the linear elastic model to calculate the displacement, mechanical stress, and mean pressure generated inside the tissue. Both the simple pressure field using a single transducer and the complex standing wave pressure field using two transducers were simulated. Main results. For the case using a single transducer, all three ARFs showed similar displacement. However, when comparing the mechanical stress results, only the results using the RSF showed a strong stress tensor at the focal point. For the case of using two transducers, the displacement and stress tensor field of the pattern related to the standing wave were calculated only from the results using the RSF. Significance. The model using RSF equation allows accurate analysis on stress tensor inside the tissue for ultrasound neuromodulation.
Image-guided focused ultrasound-mediated molecular delivery to breast cancer in an animal model
Authors: Margolis Ryan , Basavarajappa Lokesh , Li Junjie , Obaid Girgis , Hoyt Kenneth 
Published: June 2023

Abstract
Tumors become inoperable due to their size or location, making neoadjuvant chemotherapy the primary treatment. However, target tissue accumulation of anticancer agents is limited by the physical barriers of the tumor microenvironment. Low-intensity focused ultrasound (FUS) in combination with microbubble (MB) contrast agents can increase microvascular permeability and improve drug delivery to the target tissue after systemic administration. The goal of this research was to investigate image-guided FUS-mediated molecular delivery in volume space. Three-dimensional (3-D) FUS therapy functionality was implemented on a programmable ultrasound scanner (Vantage 256, Verasonics Inc.) equipped with a linear array for image guidance and a 128-element therapy transducer (HIFUPlex-06, Sonic Concepts). FUS treatment was performed on breast cancer-bearing female mice (N = 25). Animals were randomly divided into three groups, namely, 3-D FUS therapy, two-dimensional (2-D) FUS therapy, or sham (control) therapy. Immediately prior to the application of FUS therapy, animals received a slow bolus injection of MBs (Definity, Lantheus Medical Imaging Inc.) and near-infrared dye (IR-780, surrogate drug) for optical reporting and quantification of molecular delivery. Dye accumulation was monitored via in vivo optical imaging at 0, 1, 24, and 48 h (Pearl Trilogy, LI-COR). Following the 48 h time point, animals were humanely euthanized and tumors excised for ex vivo analyzes. Optical imaging results revealed that 3-D FUS therapy improved delivery of the IR-780 dye by 66.4% and 168.1% at 48 h compared to 2-D FUS (p = 0.18) and sham (p = 0.047) therapeutic strategies, respectively. Ex vivo analysis revealed similar trends. Overall, 3-D FUS therapy can improve accumulation of a surrogate drug throughout the entire target tumor burden after systemic administration.
State of the art on microbubble cavitation monitoring and feedback control for blood-brain-barrier opening using focused ultrasound
Authors: Mondou Paul , Mériaux Sébastien , Nageotte Florent , Vappou Jonathan , Novell Anthony , Larrat Benoit 
Published: June 2023

Abstract
Focused ultrasound (FUS) is a non-invasive and highly promising method for targeted and reversible blood-brain barrier permeabilization. Numerous preclinical studies aim to optimize the localized delivery of drugs using this method in rodents and non-human primates. Several clinical trials have been initiated to treat various brain diseases in humans using simultaneous BBB permeabilization and drug injection. This review presents the state of the art of in vitro and in vivo cavitation control algorithms for BBB permeabilization using microbubbles (MB) and FUS. Firstly, we describe the different cavitation states, their physical significance in terms of MB behavior and their translation into the spectral composition of the backscattered signal. Next, we report the different indexes calculated and used during the ultrasonic monitoring of cavitation. Finally, the different in vitro and in vivo cavitation control strategies described in the literature are presented and compared.
Static couch non-coplanar arc selection optimization for lung SBRT treatment planning
Authors: Lincoln John D , MacDonald R Lee , Syme Alasdair , Thomas Christopher G 
Published: June 2023

Abstract

Objective. Non-coplanar arc geometry optimizations that take advantage of beam’s eye view (BEV) geometric overlap information have been proven to reduce dose to healthy organs-at-risk (OARs). Recently, a metric called mean arc distance (MAD) has been developed that quantifies the arc geometry sampling of 4π space. The purpose of this research is to combine improved BEV overlap information with MAD to generate static couch lung stereotactic body radiotherapy (SBRT) treatment plans deliverable on a C-arm linear accelerator. Approach. An algorithm utilizing the Moller–Trumbore ray-triangle intersection method was employed to compute a cost surrogate for dose to overlapping OARs using distances interpolated onto a PDD. Cost was combined with MAD for 100 000 random combinations of arc trajectories. A pathfinding algorithm for arc selection was created, balancing the contributions of MAD and 4π cost for the final trajectory. This methodology was evaluated for 18 lung SBRT patients. Cases were also planned with arcs from a clinical treatment template protocol for dosimetric and plan quality comparison. Results were evaluated using dose constraints in the context of RTOG0915. Main results. Five of six OARs had maximum dose reductions when planned with the arc trajectory optimization algorithm. Significant maximum dose reductions were found for esophagus (7.41 ± 0.91 Gy, p = 0.00019), trachea (5.56 ± 1.55 Gy, p = 0.0025), spinal cord (2.87 ± 1.13 Gy, p = 0.039), large bronchus (3.47 ± 1.49 Gy, p = 0.0075), and aorta (3.13 ± 0.99 Gy, p = 0.012). Mean dose to contralateral lung was also significantly reduced (0.50 ± 0.06 Gy, p = 0.00019). There were two significant increases in OAR doses: mean dose to ipsilateral lung (0.40 ± 0.09, p = 0.00086) and V5Gy to ipsilateral lung (1.95 ± 0.70%, p = 0.011). Paddick conformity index increased by 0.03 ± 0.02 (p = 0.14), remaining below a limit of 1.2 for both techniques. Significance. Static couch non-coplanar optimization yielded maximum dose reductions to OARs while maintaining target conformity for lung SBRT.