bluuebunny/crossref_metadata_2025 huggingface dataset:
Weighted twisted inhomogeneous diophantine approximation
Authors: Hussain Mumtaz , Ward Benjamin
Published: October 2024

We prove a multidimensional weighted analogue of the well-known theorem of Kurzweil (1955) in the metric theory of inhomogeneous Diophantine approximation. Let

∑

i
=
1

m

α

i

=
 
m

and

|
⋅

|

α

=

max

1
⩽
i
⩽
m

|

⋅

|

1

/

α

i

. Given an n-tuple of monotonically decreasing functions

Ψ
=
 
(

ψ

1

,
…
,

ψ

n

)

with

ψ

i

:

R

+

→

R

+

such that each

ψ
i

(
r
)
→
0

as

r
→
∞

and fixed

A
∈

R

n
×
m

define

W

A

(
Ψ
)

:=

{

b

∈

[
0
,
1
]

n

:

|

A

i

⋅
q
−

b

i

−

p

i

|

<

ψ

i

(

|

q

|

α

)

(
1
⩽
i
⩽
n
)

,

for infinitely many 

(

p

,
q
)

∈

Z

n

×

(

Z

m

∖

{
0
}

)

}

.

We prove that the set

W

A

(
Ψ
)

has zero-full Lebesgue measure under convergent–divergent sum conditions with some mild assumptions on A and the approximating functions Ψ. We also prove the Hausdorff dimension results for this set. Along with some geometric arguments, the main ingredients are the weighted ubiquity and weighted mass transference principle introduced recently by Kleinbock & Wang (2023 Adv. Math.
428 109154), and Wang & Wu (2021 Math. Ann.
381 243–317) respectively.
Initial results of the Hyperion IID PET insert for simultaneous PET-MRI applied to atherosclerotic plaque imaging in New-Zealand white rabbits
Authors: Gebhardt P , Lavin B , Phinikaridou A , MacKewn J , Henningsson M , Schug D , Salomon A , Marsden P K , Schulz V , Botnar R M
Published: October 2024

Objective. In preclinical research, in vivo imaging of mice and rats is more common than any other animal species, since their physiopathology is very well-known and many genetically altered disease models exist. Animal studies based on small rodents are usually performed using dedicated preclinical imaging systems with high spatial resolution. For studies that require animal models such as mini-pigs or New-Zealand White (NZW) rabbits, imaging systems with larger bore sizes are required. In case of hybrid imaging using positron emission tomography (PET) and magnetic resonance imaging (MRI), clinical systems have to be used, as these animal models do not typically fit in preclinical simultaneous PET-MRI scanners. Approach. In this paper, we present initial imaging results obtained with the Hyperion IID PET insert which can accommodate NZW rabbits when combined with a large volume MRI RF coil. First, we developed a rabbit-sized image quality phantom of comparable size to a NZW rabbit in order to evaluate the PET imaging performance of the insert under high count rates. For this phantom, radioactive spheres with inner diameters between 3.95 and

7.86

mm were visible in a warm background with a tracer activity ratio of 4.1 to 1 and with a total 18F activity in the phantom of

58

MBq at measurement start. Second, we performed simultaneous PET-MR imaging of atherosclerotic plaques in a rabbit in vivo using a single injection containing 18F-FDG for detection of inflammatory activity, and Gd-ESMA for visualization of the aortic vessel wall and plaques with MRI. Main results. The fused PET-MR images reveal 18F-FDG uptake within an active plaques with plaque thicknesses in the sub-millimeter range. Histology showed colocalization of 18F-FDG uptake with macrophages in the aortic vessel wall lesions. Significance. Our initial results demonstrate that this PET insert is a promising system for simultaneous high-resolution PET-MR atherosclerotic plaque imaging studies in NZW rabbits.
A hybrid summation and multiplication displacement amplification mechanism for piezoelectric actuators
Authors: Wang Qihua , Gu Yuheng , Gao Hongchen , Ling Mingxiang
Published: October 2024

This paper reports a novel amplified piezoelectric actuator featuring compliant displacement amplification mechanism of hybrid summation and multiplication. The hybrid amplification mechanism uses the concept of nesting a pair of Scott–Russell linkages into a toggle linkage to realize the hybrid amplification functions of summation and multiplication. Also, compliant amplification mechanisms with double output ports are designed, enhancing the flexibility of designs and applications. The hybrid displacement amplification principle is mathematically explained in detail. It is demonstrated based on finite element simulations that the displacement amplification ratio, output stiffness and resonance frequency of the proposed hybrid amplification mechanism of summation and multiplication outperform those of the classic rhombus-type and bridge-type compliant mechanisms. The experimental testing results of a prototype show that the amplified piezoelectric actuator is capable of providing 315 μm strokes with the displacement amplification ratio of 16.2. The fundamental resonance frequency with piezoelectric stacks mounted is 1218 Hz. Comparison to typical designs in literature shows well comprehensive performances of statics and dynamics, verifying the advantages of such a hybrid amplification mechanism of summation and multiplication.
Review on high-temperature superconducting trapped field magnets
Authors: Wang Qi , Zhang Hongye , Hao Luning , Coombs Tim
Published: October 2024

Superconducting (SC) magnets can generate exceptionally high magnetic fields and can be employed in various applications to enhance system power density. In contrast to conventional coil-based SC magnets, high-temperature superconducting (HTS) trapped field magnets (TFMs), namely HTS trapped field bulks (TFBs) and trapped field stacks (TFSs), can eliminate the need for continuous power supply or current leads during operation and thus can function as super permanent magnets. TFMs can potentially trap very high magnetic fields, with the highest recorded trapped field reaching 17.89 T, achieved by TFSs. TFMs find application across diverse fields, including rotating machinery, magnetic bearings, energy storage flywheels, and magnetic resonance imaging. However, a systematic review of the advancement of TFMs over the last decade remains lacking, which is urgently needed by industry, especially in response to the global net zero target. This paper provides a comprehensive overview of various aspects of TFMs, including simulation methods, experimental studies, fabrication techniques, magnetisation processes, applications, and demagnetisation issues. Several respects have been elucidated in detail to enhance the understanding of TFMs, encompassing the formation of TFBs and TFSs, trapped field patterns, enhancement of trapped field strength through pulsed field magnetisation, as well as their applications such as SC rotating machines, levitation, and Halbach arrays. Challenges such as demagnetisation, mechanical failure, and thermal instability have been illuminated, along with proposed mitigation measures. The different roles of ferromagnetic materials in improving the trapped field during magnetisation and in reducing demagnetisation have also been summarised. It is believed that this review article can provide a useful reference for the theoretical analysis, manufacturing, and applications of TFMs within various domains such as materials science, power engineering, and clean energy conversion.
Significant enhancement in the conductivity of highly transparent PEDOT:PSS thin film through maleic acid treatment
Authors: Sau Sanjib , Kundu Sarathi
Published: October 2024

The conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS, a conducting polymer) thin film is enhanced by simply maleic acid treatment. Here, we have investigated the conductivity enhancement with the variation of maleic acid concentration. The conductivity enhances up to 1.0 M maleic acid concentration and decreases afterward. The optimum conductivity is obtained as 9.35 S cm–1, which is nearly 263 times more compared to the pristine PEDOT:PSS film. The conductivity of the film also depends upon the treating temperature. Therefore, the effect of different treating temperatures on the conductivity enhancement is studied, and the optimum temperature is found to be 140 °C. Maleic acid-treated PEDOT:PSS films also exhibit high transmittances, i.e., ≈ 90%–84% in the visible region. The mechanism related to the conductivity enhancement and other related information are collected through different spectroscopic and microscopic measurements. Besides, frequency-dependant impedance and electrochemical activity of maleic acid-treated PEDOT:PSS films are also performed. The interaction of maleic acid with PEDOT:PSS promotes the reduction of ionic interaction between PEDOT and PSS chains, resulting in the phase separation between PEDOT and PSS. As a result, the PSS– turn into neutral PSSH and are rinsed away by water, which supports the morphological change and the conductivity enhancement due to the conformational change of coil-like PEDOTs to elongated and better-connected PEDOT chains.
A variational quantum algorithm for the Poisson equation based on the banded Toeplitz systems
Authors: Liu Xiaoqi , Qu Yuedi , Li Ming , Shen Shu-Qian
Published: October 2024

To solve the Poisson equation it is usually possible to discretize it into solving the corresponding linear system Ax = b. Variational quantum algorithms (VQAs) for the discretized Poisson equation have been studied before. We present a VQA based on the banded Toeplitz systems for solving the Poisson equation with respect to the structural features of matrix A. In detail, we decompose the matrices A and A
2 into a linear combination of the corresponding banded Toeplitz matrix and sparse matrices with only a few non-zero elements. For the one-dimensional Poisson equation with different boundary conditions and the d-dimensional Poisson equation with Dirichlet boundary conditions, the number of decomposition terms is less than that reported in [Phys. Rev. A 2023 108, 032 418 ]. Based on the decomposition of the matrix, we design quantum circuits that efficiently evaluate the cost function. Additionally, numerical simulation verifies the feasibility of the proposed algorithm. Finally, the VQAs for linear systems of equations and matrix-vector multiplications with the K-banded Toeplitz matrix T

n

K
are given, where

T

n

K

∈

R

n
×
n

and

K
∈
O
(
ploylog
n
)

.
Studies on the retarded recrystallization of tungsten in CIMPLE-PSI exposed under very-high target temperature and long He+-fluence
Authors: Rahman Mizanur , Chetri Sabir , Teo S.H.B. , Thompson M. , Bilokur M. , Corr C. , Shekhar S. , Temmerman G.De. , Kakati Mayur
Published: October 2024

Experiments are carried out in CIMPLE-PSI, to understand the recrystallization behavior of tungsten (W) exposed under very-high target temperature and ITER relevant long He+-fluence. The effect of helium bubbles on possible retardation of the recrystallization process is also studied. W samples were simultaneously exposed under He plasma and annealed by the plasma heat-load, in contrast to previously reported experiments in literature, which were carried out sequentially. Exposed samples are characterized by field emission scanning electron microscopy (FESEM), Vickers surface micro-hardness, nano-hardness and electron backscattered diffraction (EBSD). It is observed that the sample exposed to plasma under the highest temperature (1866 K) suffered acute retarded grain growth. This also contained small, unrecovered grains on the exposed surface. FESEM imaging of the cross-sections confirms that relatively smaller helium bubbles still form even at very high temperature conditions, which can impede the grain growth locally, whenever they are forming right on the grain boundaries. This results in an inhomogeneous mixture of surface grains with sizes ranging from a few micrometers to a few tens of micrometers. EBSD estimates that the plasma exposed surface was only 34% recrystallized. The second sample exposed at a lower temperature (1699 K) but for three times higher fluence (ion fluence: 1.19 × 1027 m−2) was almost fully recrystallized, which shows retardation diminishes very fast with the duration of the exposure. Hardness measurements were undertaken to understand the variation with plasma exposure/annealing temperature and the extent of recrystallization, with three different probing length scales, spanning from a few hundred nanometers to several micrometers. Both helium plasma exposed W samples are observed to undergo retarded softening up to a depth of a few hundred nanometers from the surface, compared to when the metal may be recrystallized by simple heating, without any plasma exposure.
Modified Layer-based Ultrasound Imaging of Irregularly Cortical Bone
Authors: Li Yifang , Shi Qinzhen , Dai Fei , Zhang Yunyun , Xu Lexiu
Published: October 2024

Cortical bone, known for its multilayered composition with a diverse sound velocity distribution and anisotropy dependent on anatomical position, poses a challenge in conventional medical ultrasound imaging. The limitations arise due to the inability of uniform velocity to appropriately capture the intricate properties of hard tissues, leading to inaccurate reconstruction of the inner cortical layers. To tackle this complexity, a modified layer-based method utilizing a 5-layer model and estimated sound velocity was introduced for irregularly cortical bone imaging. Validated through an ex-vivo study using goat tibia, this method showcased remarkable effectiveness. The experimental outcomes revealed an ultrasound-reconstructed cortical image that closely matched the μCT-measured ground truth model, demonstrating mean cortical thickness errors of 0.31 mm. This method stands as a validated and precise approach for accurately imaging cortical bone using a 5-layer model.
Physics-Embedded Neural Networks for Enhanced Ultrasonic Brain Tomography
Authors: Ren Jiahao , Li Jian , Liu Yang
Published: October 2024

Ultrasound imaging, valued for its non-invasiveness and cost-effectiveness, faces challenges in brain imaging due to acoustic impedance differences. This study introduces PEN-UBT, a deep learning-based method, combining Convolutional Neural Network for Forward Propagation (CN-FP) and Subnetwork for Inversion (SNI). CN-FP simplifies wavefield calculations, while SNI facilitates mapping from wavefield to model. PEN-UBT achieves high-fidelity imaging of the skull and soft tissues, excelling in scenarios with varying thrombus velocities. It demonstrates exceptional tissue resolution in brain slices, reducing imaging time to 1.13 seconds. PEN-UBT’s success extends its applicability beyond brain imaging, contributing to the broader field of medical imaging technologies.
Enhancing Image Contrast in Breast USCT Reflection Imaging Using Coherence Factor Beamforming
Authors: Wang Zihao , Fan Shangchun , Ren Chujian , Wei Xiaorui , Zheng Dezhi , Wang Shuai , Xing Weiwei , Qu Xiaolei
Published: October 2024

Breast cancer is the most common cancer worldwide, and early screening is essential. Existing breast ultrasound is affordable and convenient, but its 2D image quality is poor, and it heavily relies on the doctor’s skills. The novel breast ultrasound computed tomography (USCT) can use a ring array probe to implement hundreds of single transducer emission for full-view focusing synthetic aperture reflection imaging, thereby obtaining high-resolution 3D images. However, single transducer emission results in low acoustic intensity, which further leads to low signal-to-noise ratio and low contrast of reflection images. To improve image contrast, this study incorporated beamforming with coherence factor (CF) into reflection imaging using ring transducers, promising to produce high-contrast USCT reflection images. For evaluation, we developed a USCT prototype with 2048 elements and conducted phantom experiments. We conducted phantom experiments. Results showed that the contrast achieved by the coherence factor method of the breast phantom image is improved from 24.54 dB to 63.18 dB, and the artifacts are significantly suppressed. It can be seen that the CF method could significantly improve the contrast of the breast USCT reflection image.
TC-ULM: Temporal Correlation-based Ultrasound Localization Microscopy by Deep Learning
Authors: Zhang Gaobo , Liu Xin , Li Boyi
Published: October 2024

Ultrasound Localization Microscopy (ULM) transcends the limitations of acoustic diffraction by pinpointing minuscule microbubbles (MBs), enabling detailed visualization of microvasculature at resolutions finer than the wavelength. Current approaches in ULM, inclusive of both conventional and deep learning techniques, predominantly analyze data from the ultrasound frame plane (x-y). This leaves the valuable information in the time dimension (t), especially between consecutive frames, largely untapped. This paper introduces a novel approach, Temporal Correlation ULM (TC-ULM), which harnesses temporal correlations within the y-t plane for enhanced ULM imaging. By extracting the variations of MBs over time through a sophisticated deep learning model, TC-ULM effectively reconstructs ULM images with superior quality. Empirical evidence from numerical simulations and in vivo experiments reveals that MBs exhibit a discernible pattern of continuity and local linkage across adjacent frames in the y-t plane. This key finding allows for a significant reduction in the number of frames needed for ULM, without compromising the spatial resolution. Thus, TC-ULM emerges as an innovative technique that not only retains image quality but also potentially expedites the ULM imaging process, marking a notable shift from traditional x-y plane processing methods.
Ultrasonic registration of myopic changes in the eye of Japanese quail chicks raised under the different spectrum of everyday illumination
Authors: Petronyuk Y S , Khramtsova E A , Trofimova N N , Sokolova V V , Andryuhina O M , Guryeva T S , Mednikova E I
Published: October 2024

High-resolution ultrasound techniques are employed in ophthalmology for detecting age-related changes in the eyeball’s structure, diagnosing tumours and vascular conditions. Meanwhile, acoustic microscopy methods are widely used in laboratory animal research. Our experiments utilised a short ultrasonic pulse (30-80 MHz) and B/Z-scan mode with dynamic focusing. This study utilised these parameters to measure various ocular dimensions, including the longitudinal and transverse size of the eyeball, the thickness of the lens, and the scleral-cornea, vitreous and chorioretinal complex. The sample comprised individuals of varying ages, an adult bird (65 days), and chicks across four age stages (10, 23, 36, 45 days), all studied in situ. The method enabled observation of age-related alterations in ocular structures throughout the ontogenesis of the animal, illuminated daily using an incandescent lamp alongside yellow and blue light filters. The outcomes illustrate that the measurement technique’s sensitivity detects an anterior-posterior axis (APA) escalation of quail eyes with an error range of ±15 microns. The method’s sensitivity adequately analysed the impact of the spectral composition of everyday lighting on deviations in eye development.
Numerical simulation to influence of fluid distribution on acoustic attenuation coefficient in gas water two-phase fractured media
Authors: Duan Xi , Liu Xiangjun , Liang Lixi
Published: October 2024

The equivalent fluid model simplifies the actual distribution state of fluid, and the relationship between rock elastic properties and pore fluid parameters established by the equivalent fluid model usually deviates greatly from the experimental results. A random discrete fracture model is established, and the gas-water two-phase distribution in fracture pores is described in detail. Based on the acoustic wave theory, the finite difference numerical simulation of the acoustic wave field of the rock sample model is carried out. The variation law of acoustic attenuation coefficient with saturation under the different pore fluid distribution modes is analyzed. It is of great significance to the prediction of rock pore structure and the identification of reservoir fluid.
Full-duplex two-way no-relay cross-media communication method based on acoustic wave conversion
Authors: Shang Zhigang , Miao Bailu , Qu Xinghao , Liu Songzuo
Published: October 2024

Due to the difference in acoustic impedance between water and air, the water interface becomes a natural barrier. Underwater sound waves will bounce when they propagate to the water surface. Electromagnetic waves and light waves in the air will rapidly attenuate after passing through the water surface and going underwater, making it difficult to complete air-water cross-media information transmission. In this article, we first analyze the theoretical characteristics and vibration model of the water surface after medium collision, and develop a new full-duplex communication method across the air-ocean medium, which does not rely on relay equipment and only uses three transmission media in the air. Propagate signals in the sea channel physical field to achieve two-way communication, using the mutual conversion between laser, acoustic, and radio frequency signals to fill the gap in cross-media communication technology that can simultaneously achieve two-way, full-duplex and non-relay. It has been verified through experimental installations carried out in laboratory water tanks and large comprehensive anechoic pools that it is able to achieve full-duplex communication links across the air-sea surface, indicating that the combination of laser acousticization and radio frequency-acoustic wave conversion can be used across medium full-duplex wireless communication provides a feasible method for communication that breaks through the water interface.
An Underwater Target Location Algorithm Combined with Schmidt Orthogonalization
Authors: Wang Jingyao , Sun Shilin , Li Zhe , Liu Zhen
Published: October 2024

In underwater target localization research, where challenges such as low signal-to-noise ratio and multiple interferences exist in conventional matched field processing, this paper presents a novel approach combining compressed sensing with Schmidt orthogonalization. Initially, an orthogonalization procedure is applied to the observation matrix, yielding a new matrix with reduced column coherence and maximal adherence to the Restricted Isometry Property (RIP) constraint. Subsequently, the Sparse Adaptive Matching Pursuit (SAMP) algorithm from compressed sensing is employed to reconstruct the signal, leading to precise underwater target localization. Simulation experiments substantiate that this combined approach outperforms the conventional matched field algorithm by yielding a higher signal-to-noise ratio for target acoustic source localization and markedly reducing the count of interference virtual sources. Consequently, the performance of localization for targets is substantially enhanced.
Optimization Analysis of Response Surface for Ultrasonic Welding of Battery Tabs
Authors: Yao Zhen , Ding Rongjie , Liu Kaijie
Published: October 2024

The response surface methodology was used to optimize the ultrasonic welding process parameters of battery tabs. The three process parameters of welding pressure, welding energy and welding amplitude were selected as the influencing factors, the peel strength and welding time were selected as the response variables, a three-factor and three-level experimental matrix was designed. The experimental results were analyzed by multiple regression fitting and the regression model was established. The optimal parameters derived from the model were verified. The optimum combination of process parameters is pressure (0.25Mpa), energy (649J) and amplitude (75%) with the goal of maximum peel strength and minimum welding time. The test results show that the relative error is within a reasonable range, and the established response surface model has a higher precision, which provides a certain reference for reasonable selection of ultrasonic welding process parameters for battery tabs.
Classification Method of Internal Defects in Metal Materials Based on Ultrasonic Point Cloud Data
Authors: Wang Zhongxin , Li Xue , Zhao Zheng , Li Min
Published: October 2024

The commonly used methods for analysing defects in metal materials include metallography and scanning electron microscopy(SEM). However, these methods require grinding and polishing of the material surface, which can only obtain the characteristics of material surface defects, making it difficult to effectively detect and characterize internal defects in metal materials. Therefore, a deep neural network model based on ultrasonic point cloud data was proposed in this paper, called the Global and Local Feature Fusion Network (GLFFN), to classify the internal defects in metal materials. Firstly, an ultrasonic microscope was used to perform X-layer scanning on the metal materials, obtaining ultrasonic images at different depths, from which ultrasonic point cloud data was extracted. Based on this, the GLFFN model enhances the classification accuracy of internal defects in metal materials by deep fusion of global and local features of the point cloud. With casting billets as the detection object, which contain three typical internal defects: inclusions, shrinkage cavities, and cracks. The accuracy of the new model for defect classification reached 88.24%, which is superior to the traditional methods, proving the effectiveness of the new model on the classification of internal defects in metal materials.
Acoustic fields to levitate big water drops
Authors: Cancino-Jaque Eduardo , Meneses-Diaz Josué , Carrión-Acuña Marcelo , Vargas-Hernández Yolanda , Gaete-Garretón Luis
Published: October 2024

In this report, we described the main characteristics of acoustic fields allowing the levitation of big water drops. A numerical study is presented for different configurations of levitators and their associated acoustic fields. It is shown that an emitter different to a piston-type source, for instance, a circular plate excited in its center, vibrating at its first axisymmetric eigenmode can produce an acoustic field with improved levitation capabilities.
Counter-directional mixing of longitudinal guided waves to localize multiple micro-damages in a pipe
Authors: Gu J Y , Zhu W J , Xiang Y X , Xuan F Z
Published: October 2024

Nonlinear guided wave has been considered as an effective means to detect early micro-damage in structures. In particular, the guided wave mixing technique has received great attention due to its ability to effectively isolate nonlinearity of measurement system and to localize micro-damage. Previous research mostly focuses on guided wave mixing in plate-like structures, and the research on guided wave mixing in pipes is very limited. Recent studies have been conducted on the co-directional mixing of guided waves in pipes. However, this mixing method is difficult to accurately localize multiple micro-damages because of the large mixing zone. In order to overcome these shortcomings, this study was carried out to investigate the counter-directional mixing of longitudinal guided waves in a pipe. Finite element simulations were performed on the counter-directional mixing of two primary guided waves in the pipe, and the generation of harmonic at the sum frequency was observed. The combined harmonic was used for the characterization and localization of two micro-damages in the pipe. The results show that by controlling the mixing zone of the two primary guided waves, micro-damage areas with an axial separation of 30mm can be effectively localized, which significantly improves the resolution of multiple micro-damages compared with the co-directional mixing method. Meanwhile, the relationship between the size of the mixing zone and the localization accuracy is discussed. This study provides a promising means for multiple micro-damages detection in pipes.
Effects of transducer’s Parameters on the Amplitude Response of Spirally Propagating Circumferential Lamb Wave and Their Application in Defect Detection
Authors: Lin Zuxiong , Fang Zhou , Huang Yanwei
Published: October 2024

The commonly used traditional cylindroid guided wave modes are not sensitive to a crack with limited circumferential extent within a pipe. The circumferential guide wave will not be affected by the limited circumferential extent of a crack, which can be make up the limitation of the commonly used traditional cylindroid guided wave modes in crack detecting within a pipe. This article studied the spirally propagating circumferential Lamb wave within a pipe, which can determine the axial position of a crack only if the axial extent of the crack is large enough regardless the limited circumferential extent of the crack. To efficiently trigger the spirally propagating circumferential Lamb wave, the effect of the frequency, the circumferential coverage and the axial length of the transducer on the spirally propagating circumferential Lamb wave signals were investigated based on the theoretical model and experiments. Then, the comparison experiments presented the superiority of the proposed spirally propagating circumferential Lamb wave in detecting a crack with limited circumferential extent over the commonly used cylindroid guided wave mode. Finally, the angular interval of two cracks that in the same axial position can be determined through the angular interval of the triggering positions of the spirally propagating circumferential guided wave, which cannot be evaluated through the commonly used traditional cylindroid guided wave modes.
Translations of multiple interacting bubbles in one-dimensional system
Authors: Zhang Ling Ling , Chen Wei Zhong
Published: October 2024

The pulsations and translations of N cavitation bubbles obey combined ordinary differential equations on one-dimensional chain by analyzing the pressures near the cavitation bubbles, and the translations of the cavitation bubbles are discussed. The results indicate that the cavitation bubbles with the same ambient radii at both ends move symmetrically towards or away from the middle cavitation bubble, and the secondary Bjerknes forces on the cavitation bubbles at both ends are equal in magnitude and opposite in direction and the secondary Bjerknes force on the middle cavitation bubble is zero. In addition, dynamic balance can be maintained between bubbles due to the viscous drag force, and the secondary Bjerknes forces on the cavitation bubbles at both ends are equal in magnitude and opposite in direction, and the secondary Bjerknes force on the middle cavitation bubble is almost zero. This is of immediate consequence for understanding cavitation structure formation processes in an acoustic field.
Development of PIND system based on resonant sensors and research on material identification methods for redundant particles
Authors: Ren Z C , Zou X D
Published: October 2024

Aiming at the problems of the existing particle impact noise detection (PIND) system, such as low detection accuracy, high rate of misjudgment and missed judgment, and the inability to judge the material of internal redundant particles in real time, a method for automatic detection and material identification of redundant particles based on neural network recognition is proposed, and an automatic detection system for redundant particles of sealed electronic devices is developed. The system is equipped with multi-channel piezoelectric resonant sensors, which convert the redundant particle impact noise signal into a voltage signal, and then transmit the signal to the host using a high-speed data acquisition system. The upper computer uses a short-term energy threshold detection method to extract signal pulses; Then, a variety of time and frequency domain features are extracted and combined with wavelet domain features; Finally, by training the multi output neural network prediction model, it can automatically judge whether there are redundant particles in the tested parts, and automatically give the material information of the redundant particles. Experiments show that the accuracy of the system for material recognition of redundant particles with a mass greater than 0.1 mg can reach 88.6%.
Storm surge, seawater flooding, and sea-level rise paradoxically drive fresh surface water expansion
Authors: Cantelon Julia A , Kurylyk Barret L
Published: October 2024

Coastal storms and sea-level rise (SLR) are expected to increase seawater flooding in low-elevation coastal zones. High sea levels and seawater flooding can drive groundwater table rise via ocean-aquifer connections. These dynamics are often overlooked but can cause groundwater flooding and salinization hazards, increasing freshwater security challenges for coastal communities and driving ecosystem transgressions. Field data and numerical modeling were used to evaluate how heavy rainfall, storm surge, and seawater flooding and infiltration during Hurricane Fiona (September 2022) and projected SLR impact groundwater levels, inland surface waters, and saltwater intrusion on Sable Island National Park Reserve, Canada. During the passage of Hurricane Fiona, precipitation increased groundwater and pond levels before seawater flooded the beach. Seawater flooding and infiltration caused a sharp rise in beach groundwater levels, which in turn caused inland pond levels to rise without coincident direct inputs from precipitation or seawater. Model simulations reveal that seawater infiltration on beaches flooded the subsurface and drove the observed inland groundwater rise and freshwater pond expansion. Simulations of projected SLR show that seawater flooding will only inundate a small area of land along the coast; however, inland groundwater rise and flooding, which is less well-studied, may inundate up to 30 times more land area. Further, groundwater flooding driven by rising sea levels decreases hydraulic gradients and increases saltwater intrusion via freshwater lens (FWL) contraction. Findings demonstrate that seawater flooding from coastal storms and SLR paradoxically cause concurrent fresh surface water expansion but FWL contraction. This study provides new insights into the spatiotemporal dynamics of island freshwater resources and highlights that unseen and often overlooked groundwater-surface water exchanges are critical to consider when evaluating coastal flooding and groundwater salinization hazards and management strategies for low-elevation coastlines.
Correlating FDM printing parameters with mechanical properties and surface quality of PLA printouts
Authors: Ghaffar Asim
Published: October 2024

This study explores the correlation between four critical Fused Deposition Modeling (FDM) parameters—extrusion temperature, layer height, print speed, and infill density—and the mechanical properties and surface quality of PLA (Polylactic Acid) printouts. The mechanical properties, including Young’s modulus, tensile strength, and bending strength, were evaluated alongside surface roughness and dimensional accuracy. The results indicate that extrusion temperatures between 200 °C and 220 °C optimize mechanical performance, enhancing tensile strength and bending strength, while smaller layer heights (0.1 mm) improve surface smoothness but increase print time. Moderate print speeds (around 60 mm s−1) offer the best balance between strength and efficiency, while higher infill densities (above 80%) enhance mechanical properties, increasing both tensile and bending strength by up to 25%. These findings provide key insights into optimizing FDM printing parameters to achieve improved structural integrity and aesthetic quality in PLA prints.
Introduction
Authors: Rembis Michael
Published: October 2024

The introduction presents the main historical informants for the study, people referred to in the book as “mad writers,” and outlines the main contentions of the book. Despite the limitations of their work, mad writers are essential, yet underutilized, historical informants who provide an important perspective on madness and the rise of the asylum system in the nineteenth- and early twentieth-century United States. They submitted memorials to state legislatures and appeared before investigative committees. They wrote letters, printed and sold pamphlets, and published magazine and newspaper articles and books. Recovering their stories and opening them to historical study not only reveals mad people’s experiences but also provides a richer understanding of the role of mad writers and their allies in shaping dominant relations of care and popular conceptualizations of madness. Instead of dismissing or discounting the work of mad writers, historians should read mad writing for everything it reveals.
Exposing Abuses
Authors: Rembis Michael
Published: October 2024

Although they were portrayed by asylum physicians, and by later historians, as unreliable sources, as polemical, or as excited or aggrieved, former inmates who wrote in the nineteenth century held complex, nuanced, and sometimes conflicting views about the treatment they received in the nation’s asylums. Their work both reflected and fueled the desire among the broader public to expose asylum abuses and helped mold isolated accounts of abuse into larger narratives about citizenship and the role of the state and the rising power of physicians in people’s lives. Sensational accounts of asylum abuses captured headlines and public attention, but it was the decades-long efforts of current and former inmates and their allies that bolstered mounting efforts to reform asylums in the nineteenth century.
Reckoning with Physicians
Authors: Rembis Michael
Published: October 2024

As the nineteenth century drew to a close, public pressure to reform asylums continued to mount. In response to that pressure, some turn-of-the-century physicians embarked on a campaign to transform asylums into modern mental hospitals and create new systems of classification of mental troubles. Mad writers, who continued to call for asylum reform in the early twentieth century, adapted to this changing environment by aligning themselves with sympathetic physicians and adopting some of their nosological inventions. Most mad writers stopped short, however, of a wholly uncritical alliance with physicians and mental medicine. They continued to find their own ways to think about their mental troubles and distress and, through their writing, worked to influence both popular and professional notions of madness.
Surviving Treatments
Authors: Rembis Michael
Published: October 2024

For mad writers, hospitalization was a trying experience that involved unceasing surveillance, debilitating routine, overbearing monotony, and often arduous and frightening physical interventions at the hands of physicians, nurses, and attendants. Although mad people who possessed the economic and cultural resources to do so looked to scientific medicine, to physicians, and to the hospital as a source of relief and cure for their mental troubles, they often found the interventions they encountered both unbearable and ineffective. Mad people who became deeply dissatisfied with asylum treatments used their writing to convey its inner workings to the reading public with the hope that it would bolster support for “patients’ rights” and lasting change to the asylum system.
Experimental support for partial compensation, not matched, partner response rules in blue tits
Authors: Bründl Aisha C , Lejeune Léa A , Deshpande Purabi , Mulvey Jessica E , Thiney Alice C , Chaine Alexis S , Russell Andrew F
Published: October 2024

Outcomes of theoretical models on conflict resolution between investing partners in bi-parental care systems typically predict "partial compensation" or "matched" response rules, depending on underlying assumptions. Further, although experimental tests in birds suggest that care levels by pair members are largely associated with partial compensation responses, this outcome partly depends on the type of experiment used and its effects on model assumptions. To elucidate support for both the underlying assumptions and predictions of models predicting partner compensation versus matching, we performed temporary, bi-directional brood size manipulations during late nestling provisioning in blue tits (Cyanistes caeruleus) in the French Pyrenees. We found support for assumptions of both compensation and matching models. For example, females spent more time with the brood than males, leading to potential information asymmetries on brood demand as expected by matching models. Nevertheless, both pair members changed their provisioning comparably in response to brood size manipulations, suggesting that pair members have comparable cost-benefit functions in response to variation in brood demand, as assumed under partial compensation models. Despite support for the underlying assumptions of both models, we primarily found support for predictions of partial compensation models in provisioning responses. Notably, modest changes by one member of the pair on experimental days were met with larger changes by the other, after controlling for brood size and provisioning rates on control days. Our results corroborate previous findings in blue tits using alternative experimental approaches. We suggest that future studies could benefit from understanding when partial compensation responses dominate matched ones, despite apparent asymmetries in information over brood demand.
Association between drugs and vaccines commonly prescribed to older people and bullous pemphigoid: a case–control study
Authors: Swiderski Mikolaj , Vinogradova Yana , Knaggs Roger D , Harman Karen , Harwood Rowan H , Prasad Vibhore , Persson Monica S M , Figueredo Grazziela , Layfield Carron , Gran Sonia
Published: October 2024

Background

Bullous pemphigoid (BP) is an autoimmune skin disease that mainly affects older people. Based on case series and small hospital-based studies, a number of drugs have been associated with BP. More reliable and precise estimates of associations between a broad selection of drugs/vaccines and BP will enable greater awareness of any potential increased risk of BP following the administration of certain medicines and help identify clinical, histological and genomic characteristics of drug-induced BP for different culprit drugs. Greater awareness could lead to earlier recognition or suspicion of BP and referral to a dermatologist for diagnosis. Earlier diagnosis may lead to less aggressive treatment and improved wellbeing.

Objectives

To determine the association between drugs/vaccines commonly prescribed to older people and the risk of developing BP.

Methods

We conducted a population-based nested case–control study between 1998 and 2021 using electronic primary care records from the Clinical Practice Research Datalink. We matched patients with BP with up to five controls. Exposures were drugs/vaccines commonly prescribed to older people. We used multivariable conditional logistic regression adjusting for multiple drug use. For antibiotics, in a sensitivity analysis, we considered that drugs may be prescribed for undiagnosed symptoms of BP that resemble skin infection (protopathic bias).

Results

Antibiotics were associated with the highest risk of BP [odds ratio (OR) 4.60, 95% confidence interval (CI) 4.40–4.80]. However, after adjusting for protopathic bias, the OR decreased to 2.08 (95% CI 1.99–2.17). Also, after adjusting for protopathic bias, of all the antibiotic classes and subclasses, penicillins [OR 3.44, 95% CI 3.29–3.60 (sensitivity analysis OR 1.74, 95% CI 1.66–1.84)] and penicillinase-resistant penicillins [OR 7.56, 95% CI 7.15–8.00 (sensitivity analysis OR 2.64, 95% CI 2.45–2.85)] had the strongest associations with BP risk. Other drugs strongly associated with increased risk were gliptins (OR 2.77, 95% CI 2.37–3.23) and second-generation antipsychotics (OR 2.58, 95% CI 2.20–3.03).

Conclusions

Healthcare professionals need to be aware of BP risk in older people, particularly when prescribing penicillinase-resistant penicillins, gliptins and second-generation antipsychotic drugs, to recognize and manage BP early. Owing to the low disease prevalence, we do not suggest avoiding certain drugs/vaccines to prevent BP. Further research should consider recency, dosage and duration of antibiotic treatments.
Perspectives of People With Human Immunodeficiency Virus on Implementing Long-acting Cabotegravir Plus Rilpivirine in Clinics and Community Settings in the United Kingdom: Results From the Antisexist, Antiracist, Antiageist Implementing Long-acting Novel Antiretrovirals Study
Authors: Orkin Chloe , Hayes Rosalie , Haviland Joanne , Wong Yuk Lam , Ring Kyle , Apea Vanessa , Kasadha Bakita , Clarke Emily , Byrne Ruth , Fox Julie , Barber Tristan J , Clarke Amanda , Paparini Sara ,   For the ILANA study Group, Ullah Sadna , Halim Nishat , Mwendera Chikondi , Hand James
Published: October 2024

Introduction

The equity-focused Implementing Long-Acting Novel Antiretrovirals study evaluated feasibility, acceptability, appropriateness of delivering on-label 2-monthly cabotegravir and rilpivirine (CAB + RPV) injections for human immunodeficiency virus (HIV)-1 therapy in clinics and community settings.

Methods

The study, which mandated inclusive recruitment, was conducted May–December 2022 at 6 UK sites. Injections were delivered in clinic (month [M] 1–6) and in clinic or community setting according to patient choice (M6–12). Surveys were completed at baseline, M4, and M12 using validated measures for feasibility (FIM), acceptability (AIM), and appropriateness (IAM). Primary endpoint: proportion of participants agreeing that the injection and community setting were feasible (FIM ≥4) at M12. Fourteen participants completed interviews at baseline and M12.

Results

Community settings offered by sites included: home visits (n = 3), HIV support organizations (n = 2), and community clinic (n = 1). Of 114 participants, 54% were female, 70% racially minoritized, and 40% aged ≥50 years. A total of 27/114 chose to receive injections in community settings. FIM/AIM/IAM scores at M12 were high for the injection (79.0–87.4%) and lower for the community setting (44.2–47.4%) overall. Subgroup analyses indicated differences in scores by gender and ethnicity. Among those who attended the community, FIM/AIM/IAM scores for the community setting at M12 were high (73.1–80.8%). Concerns about stigma, inconvenience, and losing access to trusted clinicians negatively influenced perceptions of receiving injections at community settings, amongst other factors.

Conclusions

CAB + RPV injections were considered highly feasible, acceptable, and appropriate; however, few chose community delivery. Those that chose community delivery found it highly acceptable and feasible. Further exploration of CAB + RPV delivery in alternative community sites not offered (eg, primary care, pharmacies) is warranted.

ClinicalTrials.gov NCT05294159