bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary care experiences in the ‘Let’s test for HPV’ study: a qualitative analysis
Authors: Borchowsky Kayden , Rush Morgan , Mullally Thomas , McBain Lynn , Hudson Ben , McMenamin John , Smith Debra , Sykes Peter , Garrett Susan
Published: June 2023

Introduction The National Cervical Screening Programme (NCSP) will switch from cervical cytology to Human Papillomavirus (HPV) testing as the primary cervical screening modality in 2023. To prepare for rollout an implementation study of HPV testing in primary care commenced in August 2022 in three different geographic regions in NZ. Aims This study explores Primary Care Staff’s experience of using the HPV testing pathway in the ‘Let’s test for HPV’ study so that recommendations can be made to improve the testing process before nationwide roll-out. Method Thirty-nine primary care staff were interviewed across all 17 practices in the Capital and Coast, Canterbury and Whanganui region participating in the ‘Let’s Test For HPV’ study. In total 19 interviews took place which followed a semi-structured approach. These interviews were recorded and transcribed. Template analysis was carried out on transcripts to aid in identifying themes. Results Three key themes, with additional subthemes, were identified. Staff were strongly supportive of the new testing regime. Interviewees identified some issues with the new pathway. Educational needs for both patients and clinicians were identified. Conclusion Primary care staff described the experience of using the HPV testing pathway positively; however, there were requests for ongoing additional support and nationwide rollout to be supported by practitioner and patient education programmes. With the right support this new pathway for cervical cancer screening has the potential to improve access for previously underserved and unserved groups.
Caught in the crossfire: Fears of Chinese–American scientists
Authors: Xie Yu , Lin Xihong , Li Ju , He Qian , Huang Junming
Published: June 2023

The US global leadership in science and technology has greatly benefitted from immigrants from other countries, most notably from China in the recent decades. However, feeling the pressure of potential federal investigations since the 2018 launch of the China Initiative, scientists of Chinese descent in the United States now face higher incentives to leave the United States and lower incentives to apply for federal grants. Analyzing data pertaining to institutional affiliations of more than 200 million scientific papers, we find a steady increase in the return migration of scientists of Chinese descent from the United States to China. We also conducted a survey of scientists of Chinese descent employed by US universities in tenured or tenure-track positions (n = 1,304), with results revealing general feelings of fear and anxiety that lead them to consider leaving the United States and/or stop applying for federal grants. If the situation is not corrected, American science will likely suffer the loss of scientific talent to China and other countries.
Cuanto(s) más datos, (tanto) mejor
Authors: Horsch Jakob
Published: June 2023

The Spanish comparative correlative (CC) construction (Cuanto más leo, (tanto)
más entiendo) has a complex syntactic structure and complex semantics. The syntactic relationship between its
two subclauses has been subject to much debate. This study, the first large-scale (> 3,000 tokens) corpus investigation,
explores various aspects and provides evidence for hypotaxis. However, statistical analysis of the data also revealed
‘under-the-surface’ parataxis. I therefore argue that the construction cannot be classified as either hypotactic or paratactic,
but as hypotactic and paratactic to certain degrees, also compared with its counterparts in English and Slovak. I argue that the
‘competition’ between hypotactic and paratactic encoding can be attributed to the principle of iconicity, that is, the “(partial)
motivation of a construction’s form by its meaning” (Hoffmann, 2019, p. 12). Finally, I
discuss various formal aspects of the Spanish CC construction that have so far gone unnoticed, providing new evidence in the form
of corpus data.
ArchEnemy: removing scattered-light glitches from gravitational wave data
Authors: Tolley Arthur E , Cabourn Davies Gareth S , Harry Ian W , Lundgren Andrew P
Published: June 2023

Data recorded by gravitational wave detectors includes many non-astrophysical transient noise bursts, the most common of which is caused by scattered-light within the detectors. These so-called ‘glitches’ in the data impact the ability to both observe and characterize incoming gravitational wave signals. In this work we use a scattered-light glitch waveform model to identify and characterize scattered-light glitches in a representative stretch of gravitational wave data. We identify 2749 scattered-light glitches in 5.96 days of LIGO-Hanford data and 1306 glitches in 5.93 days of LIGO-Livingston data taken from the third LIGO-Virgo observing run. By subtracting identified scattered-light glitches we demonstrate an increase in the sensitive volume of a gravitational wave search for binary black hole signals by

∼

1
%

.
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

To 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

We 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

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

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

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

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

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

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

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

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

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

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

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

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.
Low-count PET image reconstruction based on truncated inverse radon layer and U-shaped network
Authors: Ye Jianbo , Kuang Zhonghua , Yang Yongfeng , Cui Ke , Li Xiangyu
Published: June 2023

Objective. Positron emission tomography (PET) is a functional imaging widely used in various applications such as tumour detection. PET image reconstruction is an ill-posed inverse problem, and the model-based iterative reconstruction methods commonly used in clinical practice have disadvantages such as long time consumption and low signal-to-noise ratio, especially at low doses. Approach. In this study, we propose a deep learning-based reconstruction method that is capable of reconstructing images directly from low-count sinograms. Our network consists of two parts, a truncated inverse radon layer for implementing domain transform and a U-shaped network for image enhancement. Main result. We validated our method on both simulation data and real data. Compared to ordered subset expectation maximization with a post-Guassian filter, the structural similarity can be improved from 0.9357 to 0.9613 and the peak signal-to-noise ratio can be improved by 5 dB. Significance. The proposed method can directly convert low-count sinograms into PET images, while obtaining improved image quality and having less time consumption than iterative reconstruction algorithms and the state-of-the-art convolutional neural network.
Utilizing the Peltier effect for actuation of thermo-active soft robots
Authors: Exley Trevor , Johnson Daniel , Jafari Amir
Published: June 2023

The field of soft actuation methods in robotics is rapidly advancing and holds promise for physical interactions between humans and robots due to the adaptability of materials and compliant structures. Among these methods, thermally-responsive soft actuators are particularly unique, ensuring portability as they do not require stationary pumps, or high voltage sources, or remote magnetic field. However, since working principles of these actuators are based on Joule heating, the systems are inefficient and dramatically slow, especially due to their passive cooling process. This paper proposes using the Peltier effect as a reversible heating/cooling mechanism for thermo-active soft actuators to enable faster deformations, more efficient heat transfer, and active cooling. The proposed actuator is composed of a thin elastic membrane filled with phase-change fluid that can vaporize when heated to produce large deformations. This membrane is placed in a braided mesh to create a McKibben muscle that can lift 5 N after 60 s of heating, and is further formed into a gripper capable of manipulating objects within the environment. The effectiveness of the proposed actuator is demonstrated, and its potential applications in various fields are discussed.
Anomalously small magnetic relaxation rate of Ca10(Pt3As8)(Fe2−x
Pt
x
As2)5 superconductor
Authors: Meng Yan , Sun Yue , Xing Xiangzhuo , Tamegai Tsuyoshi , Shi Zhixiang
Published: June 2023

Large critical current density and low magnetic relaxation are the main challenges for practical applications of high-temperature superconductors (HTSs). Magnetic relaxation refers to the decay of superconducting current density caused by thermal activation and/or quantum fluctuations. This process involves the motion of vortices, particularly vortex creep, which leads to energy dissipation. HTSs typically exhibit strong superconducting fluctuations and magnetic relaxation due to their short coherence length and large anisotropy. These characteristics are usually manifested by the large Ginzburg number Gi and high magnetic relaxation rate S. The correlation between the relaxation rate S and Gi is informative to understand the interplay between vortex dynamics and relevant parameters. Recently, Eley et al (2017 Nat. Mater.
16 409) proposed that almost all the HTSs follow a universal lower limit S∼ Gi
1/2(T/T
c), providing new clues to design HTSs with small relaxation rate and evaluate their application potential. Here, we systematically studied the vortex dynamics in the Ca10(Pt3As8)(Fe2−x
Pt
x
As2)5 superconductor with a large Gi∼ 0.16. Strikingly, this material exhibits a small relaxation rate (S ∼0.02 at T
c/4 under 1 T), approaching the proposed lower limit of S∼ Gi
1/2(T/T
c). We propose that such a small value of S in Ca10(Pt3As8)(Fe2−x
Pt
x
As2)5 may originate from its unique structure with metallic skutterudite blocking layers. Our results suggest a promising new avenue for the search and design of HTSs with low magnetic relaxation.
Effects of interior angle and inclination angle of slot defect on electromagnetic-stress behaviours of superconducting swing system
Authors: Yu Zhiqiang , Zhao Xiaosha , Feng Wenjie , Zong Yinlu , Yue Chuan , Jing Liwei , Pei Lingben , Tong Dayan
Published: June 2023

Currently, copper-oxygen high-temperature superconducting materials have strongly anisotropic electromagnetic properties, which are difficult to describe in the equations. And in the rotating machine containing the permanent magnet (PM) rotor and bulk high-temperature superconductor (HTS) stator, when the HTSs have defects, their electromagnetic-stress behaviours may affect the mechanical stability of the equipment and even cause it to not work properly. In this paper, we proposed an anisotropic electromagnetic equation based on the H-formulation and established a three-dimensional coupled model with the magnetic, thermal and stress fields to study the electromagnetic-stress behaviours of a HTS with a slot defect during the swing of a PM, discussing the effects of the interior angle and inclination angle of the defect on the behaviours. The results show that the interior and inclination angles of the defect have a large influence on the electromagnetic-stress behaviours. For the electromagnetic characteristics, the main influence is on the rotational losses. Especially the losses at an inclination angle of 60° are 16.5 times those without damage. This is related to the ‘thin wall’ structure near the upper surface of the HTS. The stress concentration point appears on the defect boundary. The novelty of this paper is the proposal of the anisotropic electromagnetic equations based on the H-formulation and the study of the electromagnetic-stress behaviours of a superconducting swing system containing a PM and HTS with a slot defect from a three-dimensional perspective. The research results of this paper can be the references for the design and structural protection of superconducting rotating machines.
Implementation of coherence imaging spectroscopy for ion flow measurements in the Compact Toroidal Hybrid experiment
Authors: Allen N.R. , Ennis D.A. , Allen S.L. , Samuell C.M. , Kriete D.M. , Johnson C.A. , Hartwell G.J. , Maurer D.A.
Published: June 2023

A new coherence imaging spectroscopy (CIS) system has been
characterized and validated for measurements of impurity ion
velocity in the Compact Toroidal Hybrid (CTH) experiment. CIS is an
interferometric technique providing very high spatial resolution of
line-integrated ion flows; however, these measurements are highly
sensitive to environmental factors such as temperature fluctuations.
A compact interferometer design housed in a thermally regulated
environment yields CIS measurement variations due to thermal
fluctuations of 0.25 km/s. CIS measurements of He+ flows in
the outer regions of CTH are benchmarked using two optical grating
spectrometers. The deviation between the measurements is typically
less than 2 km/s for multiple lines of sight which is well within
the uncertainties of the diagnostics. Additional experiments
demonstrate a moderate robustness of ion flows in the outer region
of CTH to changing the vacuum transform, direction of the magnetic
field, and plasma current. In contrast, regions of complete flow
reversal are observed when a bias probe is inserted into the plasma
edge.
Characterization of the response of IHEP-IME LGAD with shallow carbon to Gamma Irradiation
Authors: Sun Weiyi , Fan Yunyun , Zhao Mei , Cui Han , Yu Chengjun , Li Shuqi , Feng Yuan , Huang Xinhui , Liang Zhijun , Jia Xuewei , Wang Wei , Wu Tianya , Li Mengzhao , da Costa João Guimarães , Xu Gaobo
Published: June 2023

Low Gain Avalanche Detectors (LGAD) for the High-Granularity Timing Detector (HGTD) are crucial in reducing pileups in the High-Luminosity Large Hadron Collider. Numerous studies have been conducted on the bulk irradiation damage of LGADs. However, few studies have been carried out on the surface irradiation damage of LGAD sensors with shallow carbon implantation. In this paper, the IHEP-IME LGADs with shallow carbon implantation were irradiated up to 2 MGy using gamma irradiation to investigate surface damage. Important characteristic parameters, including leakage currents, breakdown voltage (BV), inter-pad resistances, and capacitances, were tested before and after irradiation. The results showed that the leakage current and BV increased after irradiation, whereas overall inter-pad resistance exhibited minimal change and remained above 109 Ω before and after irradiation. Capacitance was found to be less than 4.5 pF with a slight decrease in the gain layer depletion voltage (V
gl
) after irradiation. No parameter affected by the inter-pad separation was observed before and after irradiation. All characteristic parameters meet the requirements of HGTD, and this design can be used to further optimization.
Self-stimulating sandwich structure with resistive heating honeycomb core for quick thermographic inspection
Authors: Tříska Václav , Hnidka Jakub , Rozehnal Dalibor
Published: June 2023

The paper presents the novel concept of a honeycomb sandwich structure with carbon fibre reinforced plastics face sheets capable of its own internal thermal stimulation for rapid active thermographic inspection, where an adapted electrically powered honeycomb core serves as a heat source. The proposed sandwich structure effectively reduces the equipment necessary for external thermal stimulation, while improving the controllability of the thermal pulse. A new design of the modified aluminum honeycomb core, required for resistance heating with sufficient homogeneity, is proposed. Numerical modeling was used to test the concept’s viability and to predict its efficiency for defect detection. The altered honeycomb was then manufactured and its heating characteristics were measured. This structure was then used as a core in a sandwich specimen with carbon fibre reinforced plastics face sheets, which also contained artificial defects embedded in the face sheets and in the face sheet/core interface. The applicability of the proposed modified honeycomb structure for thermal stimulation for active infrared thermography was experimentally confirmed, demonstrating the ability to visualize even very small defects simulating disbonding, or delamination. The impact of water ingress on the operation of the concept was tested as well. The proposed method has the potential to simplify and expedite the non-destructive inspection of aviation-grade sandwich structures in service via active infrared thermography.
Current-density functional theory for bosonic superfluids
Authors: Aizawa Tomoya , Higuchi Masahiko , Higuchi Katsuhiko
Published: June 2023

A finite-temperature current-density functional theory for bosonic superfluids (sf-CDFT) in the thermal equilibrium state is proposed herein. In the sf-CDFT, hydrodynamic physical quantities, such as particle number density, current density, and the order parameter of the Bose–Einstein condensation, are chosen as the basic variables. This theory enables the simultaneous reproduction of the particle number and current densities of both the superfluid and normal fluid components with incorporating effects of the interaction between these components. Specifically, these components are determined by solving two single-particle equations, i.e., the Gross–Pitaevskii–Kohn–Sham and Kohn–Sham equations. Furthermore, using the continuity equation of superfluids, we present the sum rule for the exchange-correlation energy functional of the sf-CDFT, which is useful for developing the approximate form.
Direct observation of the magnetic anisotropy of an Fe(II) spin crossover molecular thin film
Authors: Dale Ashley S , Yazdani Saeed , Ekanayaka Thilini K , Mishra Esha , Hu Yuchen , Dowben Peter A , Freeland John W , Zhang Jian , Cheng Ruihua
Published: June 2023

In this work, we provide clear evidence of magnetic anisotropy in the local orbital moment of a molecular thin film based on the SCO complex [Fe(H2B(pz)2)2(bipy)] (pz = pyrazol−1−yl, bipy = 2,2′−bipyridine). Field dependent x-ray magnetic circular dichroism measurements indicate that the magnetic easy axis for the orbital moment is along the surface normal direction. Along with the presence of a critical field, our observation points to the existence of an anisotropic energy barrier in the high-spin state. The estimated nonzero coupling constant of ∼2.47 × 10−5 eV molecule−1 indicates that the observed magnetocrystalline anisotropy is mostly due to spin–orbit coupling. The spin- and orbital-component anisotropies are determined to be 30.9 and 5.04 meV molecule−1, respectively. Furthermore, the estimated g factor in the range of 2.2–2.45 is consistent with the expected values. This work has paved the way for an understanding of the spin-state-switching mechanism in the presence of magnetic perturbations.
The role of sea ice in establishing the seasonal Arctic warming pattern
Authors: Sejas Sergio A , Taylor Patrick C
Published: June 2023

In response to a positive CO2 forcing, the seasonal Arctic warming pattern is characterized by an early winter maximum and a summer minimum. While robust, our fundamental understanding of the seasonal expression of Arctic surface warming remains incomplete. Our analysis explores the relationship between the seasonal cycle of surface heating rate changes and the seasonal structure of Arctic warming in modern climate models. Consistent across all models, we find that the background summer-to-winter surface cooling rate and winter-to-summer surface heating rate slows over sea ice regions in response to increased CO2. The slowing of the background summer-to-winter surface cooling rate leads to an early winter Arctic warming maximum, whereby regions and models with a greater slowing also produce a greater winter warming peak. By decomposing the contributions to the background seasonal heating rate change, we find that reductions in sea ice cover and thickness are primarily responsible for the changes. The winter warming peak results from the loss of sea ice cover, which transitions the Arctic surface from a lower thermal inertia surface (sea ice) to a higher thermal inertia surface (ice-free ocean) that slows the seasonal cooling rate. The seasonal cooling rate in autumn is further slowed by the thinning of sea ice, which allows for a greater conductance of heat from the ocean through the sea ice to the surface. These results offer an alternate perspective of the seasonality of Arctic warming, whereby the changing thermal inertia of the Arctic surface is an important aspect of the seasonality, complementary to other perspectives.
Ultrafast Arctic amplification and its governing mechanisms
Authors: Janoski Tyler P , Previdi Michael , Chiodo Gabriel , Smith Karen L , Polvani Lorenzo M
Published: June 2023

Arctic amplification (AA), defined as the enhanced warming of the Arctic compared to the global average, is a robust feature of historical observations and simulations of future climate. Despite many studies investigating AA mechanisms, their relative importance remains contested. In this study, we examine the different timescales of these mechanisms to improve our understanding of AA’s fundamental causes. We use the Community Earth System Model v1, Large Ensemble configuration (CESM-LE), to generate large ensembles of 2 years simulations subjected to an instantaneous quadrupling of CO2. We show that AA emerges almost immediately (within days) following CO2 increase and before any significant loss of Arctic sea ice has occurred. Through a detailed energy budget analysis of the atmospheric column, we determine the time-varying contributions of AA mechanisms over the simulation period. Additionally, we examine the dependence of these mechanisms on the season of CO2 quadrupling. We find that the surface heat uptake resulting from the different latent heat flux anomalies between the Arctic and global average, driven by the CO2 forcing, is the most important AA contributor on short (<1 month) timescales when CO2 is increased in January, followed by the lapse rate feedback. The latent heat flux anomaly remains the dominant AA mechanism when CO2 is increased in July and is joined by the surface albedo feedback, although AA takes longer to develop. Other feedbacks and energy transports become relevant on longer (>1 month) timescales. Our results confirm that AA is an inherently fast atmospheric response to radiative forcing and reveal a new AA mechanism.
Age and Sex Differences in the Associations Among Socioeconomic Status, Affective Reactivity to Daily Stressors, and Physical Health in the MIDUS Study
Authors: Jiang Yanping , Knauft Katherine M , Richardson Clarissa M E , Chung Tammy , Wu Bei , Zilioli Samuele
Published: June 2023

Background

Low socioeconomic status (SES) is robustly associated with increased risks of morbidity and mortality. Affective reactivity to daily stressors has been proposed to be a mediator for this association. However, few longitudinal studies have empirically tested the indirect effect of SES on health through affective reactivity to daily stressors.

Purpose

This study aimed to test the indirect effect of SES on physical health via affective reactivity to daily stressors over a 10-year period and to explore age and sex differences in such indirect effect.

Methods

Data were drawn from a subsample of 1,522 middle-aged and older adults (34–83 years of age, 57.2% female, 83.5% White) from the Midlife in the United States study. SES (i.e., education, household income, indicators of financial distress) was assessed in 2004–2006. Affective reactivity to daily stressors was computed using data collected during the 8-day daily stress assessment in 2004–2009. Self-reported physical health conditions were assessed in 2004–2006 and 2013–2014.

Results

There was a significant indirect effect of lower SES on more physical health conditions via elevated negative affective reactivity to daily stressors among women but not men. The indirect effect of SES on physical health conditions via negative affective reactivity to daily stressors was consistent across the middle and older adulthood.

Conclusions

Our findings suggest that negative affective reactivity to daily stressors might be a key intermediate process contributing to persistent SES disparities in physical health, particularly among women.
Defending the Hypothetical Author
Authors: Lin Szu-Yen
Published: June 2023

In contemporary analytic philosophy of art, the intentionalist debate is about whether the author’s intention is relevant to the interpretation of her work. Various positions have been proposed, and in this paper I defend what I call hypothetical author-hypothetical intentionalism, the position that interpretation is based on the intention attributed to the author constructed from the work. There are three aims to achieve: (1) to give a general account of hypothetical author-hypothetical intentionalism; (2) to present a moderate version of hypothetical author-hypothetical intentionalism; (3) to defend the moderate version of hypothetical author-hypothetical intentionalism against actual intentionalism and actual author-hypothetical intentionalism. Against the current trend that focuses on actual authors, I hope to show that the hypothetical author account is still a sustainable contender in the intentionalist debate.