bluuebunny/crossref_metadata_2025 huggingface dataset:
Two-dimensional distribution experiment of ‘lattice diffraction’ using ultrasound in an educational laboratory
Authors: Chai Yijie , Wang Qixi , Lu Aijiang , Huang Xiaojiang , Tang Xiaoliang , Xu Yu
Published: September 2024

A device that can study the two-dimensional distribution of ultrasonic diffraction on lattice structures was developed for educational laboratories, enabling students to design the size, shape and dimension of diffraction obstacles independently. In this experiment, metal balls were used to simulate atomic lattice structures, and the two-dimensional diffraction distribution data of simple cubic, body-centered cubic, and hexagonal close-packed structure were collected. The results were compared with the sound field simulation of COMSOL, and a good consistency was found. By observing the diffraction results of complex structures, students can gain a better understanding of the concept of diffraction.
Effects of die top system and trenches on large thin die mechanical robustness
Authors: Gupta Nikhil , Poelma René , Zhang GuoQi , Driel W D van , van Zeijl HW
Published: September 2024

Power MOSFET dies in the automotive industry are becoming larger (>5 × 5 mm) and thinner (<50 µm) to meet high-performance and lifetime requirements. Ensuring the mechanical robustness of these large ultrathin chips is crucial for reliable electronic devices and high-throughput packaging processes. The high aspect ratio and advanced chip designs incorporating trench technology present significant challenges in semiconductor assembly, packaging, and testing. This paper introduces an experimental front-end strategy aimed at strengthening the front side (FS) of large ultrathin dies using various die-top systems. Industry-equivalent 50 µm thick dummy power MOSFET dies were fabricated to evaluate the efficacy of different chip designs and materials, such as polyimide (PI), in mitigating fracture risks. Fabrication-induced stresses and warpage in the device layers were measured using a thin-film stress measurement tool. Additionally, the FS strength of the ultrathin dies was assessed using the three-point bending method, with the resulting data analyzed via two-parameter Weibull distribution plots. Results demonstrated that the deposition of 5 µm PI on the nitride die topside significantly increased die strength from 339 MPa to 760 MPa, with 5 µm PI proving more effective for die strengthening than 10 µm. The interaction between the metal-trench layer and the die was found to be critical to the robustness of ultrathin dies, influenced by the pattern and layout of the trenches. Die-top metallization designs, such as meandering patterns, showed promising improvements in die strength compared to standard designs. A proposed chip layout aims to maximize PI coverage for clip-bonded products on the die topside, leveraging its strengthening effect. The study also demonstrated that dummy reference chips can facilitate rapid and straightforward evaluation of extensive design experiments to identify robust chip designs.
Impact of c- and m- sapphire plane orientations on the structural and electrical properties of β-Ga2O3 thin films grown by metal-organic chemical vapor deposition
Authors: Serquen E , Bravo F , Chi Z , Enrique L A , Lizárraga K , Sartel C , Chikoidze E , Guerra J A
Published: September 2024

This work presents a comprehensive investigation into the structural and electrical properties of Ga2O3 thin films grown via metal-organic chemical vapor deposition on both c- and m-plane sapphire substrates. Structural characterization revealed the β-Ga2O3 phase formation in both substrate orientations, with strong epitaxial

(

2
¯

01
)

preferential growth on c-plane substrates and polycrystalline films on m-plane substrates. Results show that Ga2O3/m-sapphire exhibits the lower electrical resistivity than its counterpart grown on c-sapphire. Activation energies of acceptor levels were estimated at ~1.4 

eV

and ~0.7 

eV

, for Ga2O3 films grown on c- and m-plane, respectively. This result shows that growing Ga2O3 on m-plane sapphire is beneficial to reach a weakly compensated sample. Cathodoluminescence analysis suggests that the additional low activation energy of ~0.18 

eV

observed in Ga2O3 grown with the highest oxygen flow on m-plane sapphire can be associated to thermally-induced migration of self-trapped hole states.
CP-RDM: a new object detection algorithm for casting and pouring robots
Authors: Zhao Kanghui , Miao Xingang , Xia Jianqiang , Li Jiaping
Published: September 2024

Automating the casting sector heavily relies on pivotal technology for object detection in pouring robots. A sophisticated algorithm designed to identify and locate target pouring holes in intricate casting workshops is crucial for advancing the intelligence of the casting process. However, the workshop environment for pouring is generally challenging, with uneven lighting, varying sizes of pouring holes, and significant occlusion in the target area, all impacting the accuracy of target detection tasks. To overcome these challenges, this paper proposes enhancing the YOLOv8s algorithm for object detection in pouring robots. Firstly, to address the issue of different scales in pouring holes, a Multi-Scale Residual Channel and Spatial Information Fusion Module (MRCS) is designed to aggregate channel and spatial information, thereby enhancing the feature extraction capability of the model. The proposed enhancement is validated on the Pascal VOC dataset. Secondly, a SimAM attention mechanism is added at the end of the backbone network to focus the object detection network more on the positional region of the pouring hole. Importantly, this addition does not introduce extra parameters or computational burden to the model. Finally, in the detection part of the model, the detection head from the RT-DETR model is introduced. This combination of real-time detection capability from YOLO and deep feature extraction capability from RT-DETR enhances the detection accuracy of the model while ensuring real-time performance. Experimental results on the updated pouring hole dataset reveal that, with only a slight increase in parameters, the proposed model achieves a 2.5% and 3.5% improvement in mAP@0.5 and F1-Score, respectively, compared to the baseline algorithm YOLOv8s. Precision (P) is enhanced by 1.8%, recall (R) by 3.5%, and PFS reaches 110, meeting the requirements for real-time pouring in pouring robots.
Automatic classification method for water entry sounds in multi-interference environments
Authors: Liu Tianhe , Duan Rui , Yang Kunde , Su Benxue
Published: September 2024

In marine environments with strong pulse interference, distinguishing water entry sounds from pulse interference with high accuracy presents a challenge. Conventional algorithms that only utilize the singular values of intrinsic mode functions (IMFs) as the classification feature can have many misclassified signals in noisy environments. To identify the water entry sound more precisely, this study introduces a classifier based on selected singular value and correlation coefficient features. Specifically, the correlation coefficient between each IMF and the original signal are used to select crucial singular values and eliminate uninformative components. Furthermore, the correlation coefficient also combines with singular values as classification features for water entry sounds. The classification experiment results of 2460 groups of water entry sound and pulse interference indicate that the proposed classifier improves classification accuracy by approximately 11.5% compared to using singular values alone and by approximately 2.4% compared to classification accuracy without eliminating uninformative IMFs.
Novel hybrid interference and atomic force microscopy
Authors: Dai Gaoliang , Jiao Ziyang , Rao Xingyu , Wolff Helmut , Tutsch Rainer
Published: September 2024

A novel hybrid microscope which combines an interference microscopic (IM) and an atomic force microscopic (AFM) measurement mode is introduced. It is realised by adding an AFM probe to an IM, where the AFM probe can be mechanically switched in or out of the beam path of the IM. When the AFM cantilever is out of the beam path, the system works in the IM measurement mode for noncontact and fast optical measurements. When the AFM cantilever is in the beam path, it works in the AFM measurement mode, where the AFM tip interacts with sample surfaces for measurements. The deformation of the AFM cantilever induced by the tip-sample interaction force is detected from interference fringes, which are formed by the interference of the light beam reflected from the backside of the AFM cantilever and a reference beam in the IM. This novel design has a high-level synergy of AFM and IM technologies and provides promising application potentials. For instance, the limited resolution capacity of the IM mode can be complemented by the high-resolution AFM. AFM measurements are capable of offering measurement results with higher topography fidelity than IM measurements, thus for providing in-situ reference areal surface metrology. In the paper, design concept, realisation of a prototype instrument, and experimental results illustrating the performance of the prototype instrument are detailed.
Singular limit of a chemotaxis model with indirect signal production and phenotype switching
Authors: Laurençot Philippe , Stinner Christian
Published: September 2024

Convergence of solutions to a partially diffusive chemotaxis system with indirect signal production and phenotype switching is shown in a two-dimensional setting when the switching rate increases to infinity, thereby providing a rigorous justification of formal computations performed in the literature. The expected limit system being the classical parabolic–parabolic Keller–Segel system, the obtained convergence is restricted to a finite time interval for general initial conditions but valid for arbitrary bounded time intervals when the mass of the initial condition is appropriately small. Furthermore, if the solution to the limit system blows up in finite time, then neither of the two phenotypes in the partially diffusive system can be uniformly bounded with respect to the L
2-norm beyond that time.
Research on dynamic performance and mechanical model of a novel magnetorheological shear thickening damper with adaptive variable damping gap
Authors: Zhao Qian , Wang Kan , Yuan Jing , Jiang Huiming
Published: September 2024

Magnetorheological shear thickening fluid (MRSTF) is an intelligent composite material, which shows considerable potential in semi-active vibration control. However, the current research is mostly limited to the study of the rheological properties of materials, and there is still a lack of damper structures that can effectively utilize the dual-control characteristics of MRSTF. In this paper, a novel damper structure with adaptive adjustable damping gap length is proposed. Its unique design integrates an adaptive internal damping gap that changes with the movement of the piston and an external gap controlled by the magnetic field, providing a relatively wide range of current-controlled damping force and reliable adaptive adjustment capabilities. Based on the M-S shear stress constitutive model and structural characteristics, the mechanical model is derived from the force balance of the micro-element, and verified by performance test and curve fitting. The effectiveness of the new damper structure proposed in this paper is verified by dynamic performance test. The results show that the damper has a wide range of current controlled damping force at low speed and reliable adaptive adjustment capability at high speed. Finally, the accuracy and universality of the modified mechanical model of damper are verified by curve fitting method. All these studies can offer an effective guidance for further application of MRSTF in the field of semi-active vibration control.
A composite control method of PWM and phase shift for a three-level DC-DC converter
Authors: Li Yang , Zuo Dongsheng , Zhang Haoran
Published: September 2024

This research introduces a control strategy for the Three Level Active Half Bridge (TL-DAHB) DC-DC converter that integrates PWM combined with phase-shift control. This composite control method precisely regulates the output voltage by adjusting the phase-shift duty cycle between the input and output sides. Additionally, the application of the PWM control loop optimizes the duty cycle of the switches, effectively reducing the current stress on the converter during operation, improving transmission efficiency, and decreasing conduction losses of the switches. These enhancements boost the overall performance and the reliability of the converter. With its excellent voltage regulation capabilities and safety features, this converter is an ideal choice in the field of power conversion, especially in applications that demand high levels of stability and safety.
Construction of small size and high output triboelectric nanogenerator by multi-layer-stacking and charge excitation
Authors: Li Gui , Li Wen , Wang Jian , Xu Shuyan , Fu Shaoke , Shan Chuncai , Wu Huiyuan , An Shanshan , Wang Ping
Published: September 2024

The triboelectric nanogenerator (TENG) has been considered a low-frequency mechanical energy collection and conversion device in the modern era. The reasonable stack structure of TENG is an effective method to boost its electric output performance within a limited space. Nevertheless, relying solely on the stacking structure, the TENG is unable to produce excessive output due to the low contact electrification capability of its materials. Hence, there are still significant challenges in enhancing the output performance of stacked TENGs. We propose a multi-layer-stack TENG (M-TENG) with two zigzag-shaped (Z-shaped) multilayer units interleaving and stacking with each other, which enormously enlarges the effective utilization area. Furthermore, a voltage multiplier circuit (VMC) incorporating a Zener diode allows the transfer charge to approach the critical threshold and maintain a stable output. The transfer charge and current of M-TENG integrated with a VMC can reach 1.52 μC and 86 μA, respectively, with the maximum output of the TENG being 8.65 mW (5 MΩ). To prove it as a self-power device, M-TENG excited by a VMC is employed to power 912 light-emitting diodes (LEDs) and three temperature and humidity sensors with a power management circuit (PMC), respectively. This work offers a new method for optimizing stacking-layer TENG electric output performance in a narrow space.
Modeling of the conditions of the process of biotransformation of fish raw materials by bacterial starter cultures
Authors: Lavrukhina E V , Zarubin N Y , Bredikhina O V , Grinevich A I , Arkhipov L O
Published: September 2024

In food biotechnology, special attention is given to the biotransformation by promising strains of bacterial starter cultures to obtain food products with improved quality characteristics and functional properties. Biotransformation using bacterial starter cultures may be a means to increase the shelf life of fish products, enhance their organoleptic properties, and increase their nutritional value through the formation of metabolites of their activity, which are the main factors of bioconservation and synthesis of vitamins and other biologically active substances. The probiotic properties of bacterial starter cultures will significantly influence the optimization of the indigenous microflora of the gastrointestinal tract, thereby strengthening the human body and its immune system overall to maintain a healthy lifestyle. The development of this trend is associated with the interest of the Russian population in products with a probiotic focus. In this regard, an analysis of data on the justification of the use of bacterial starter cultures for the biotransformation of fish raw materials has been conducted, and the necessary bacterial starter cultures have been selected. Based on theoretical and practical foundations, mathematical models of the biotransformation process by bacterial starter cultures have been constructed depending on the properties of fish raw materials and the biotechnological characteristics of the introduced microorganisms. The conducted research has been used to develop subsequent technological regimes for the biotransformation of fish raw materials by bacterial starter cultures as the basis for the formulations of “fast food” products containing functional components, which is justified by the accelerated pace of life and the desire of modern society to monitor their diet by consuming products that support a healthy lifestyle.
Detection and estimation of 3D shape of waste based on neural networks
Authors: Viatkin D , Malysheva S
Published: September 2024

This article considers the possibility of using neural networks to detect and recognize different types of waste and determine its shape. The developed algorithm can be used to automate the waste sorting process for further sorting, recycling or disposal. This article deals with the detection of 28 classes of objects made of iron, plastic, cardboard and glass with varying degrees of deformation and damage. The detection is based on the YOLO8 neural network. The quality of the YOLOv8 model was evaluated on test data using the following metrics: box_loss, cls_loss, dfl_loss, mAP50, mAP50-95, precision, recall. After training the neural network, the YOLOv8 metrics on the test data are: box_loss=1.14, cls_loss=2.21, dfl_loss=1.21, mAP50=0.48, mAP50-95=0.38, precision=0.60, recall=0.44. The 3d shape detection is done after analyzing the image by YOLOv8 model based on GLPN neural network.
Spatial and temporal evolution and drive mechanism of tourism ecological security based on DPSIRM-SBM model
Authors: Peng Guochuan , Zhang Fengtai , Yang Xingyu , Ma Dalai , Tan Hongmei
Published: September 2024

Tourism ecological security is an important indicator of the sustainable development of tourist destinations. Considering the complete embodiment of human social factors, the DPSIRM-SBM Model is cited and improved. Taking tourism ecological security of the Yangtze River Economic Belt as the research object, the characteristics of temporal and spatial evolution and its influencing mechanism are analyzed, aiming at making a scientific, comprehensive and systematic evaluation. It is found that the tourism ecological security of the Yangtze River Economic Belt is between sensitive and general security levels; Formed a spatial pattern with strong two ends and weak middle; The security advantages at the junction of provincial administrative regions are obvious; Regional differences first increase and then decrease, which accords with the theory of unbalanced growth;In terms of spatial agglomeration, the main type in YREB as a whole shifted from an initial downstream high-value agglomeration to a midstream low-value agglomeration; Sustainable tourism is affected by comprehensive factors, economic growth is not the main driving force, the construction of ecological civilization is very important.
Urban air quality comparison on bike and driving routes: a case study for UK
Authors: Babu Saheer Lakshmi , Ahmadpoor Negar , Thundikandi Maroli Jayasooryan
Published: September 2024

Air quality in cities is very important in both tackling climate change and promoting healthy sustainable urban living. Understanding the air quality around cities has been a challenge faced by local authorities around the world. With the new net zero targets in place, government and charitable organisations across the UK have been trying hard to both monitor and control air pollutants to influence citizen behavior towards environmentally friendly living. This study looks at urban air quality in two UK cities with the idea of understanding air quality and its relation to the mode of transport, health and well-being. This case study compares the urban air quality as Particulate Matter (PM
10 and PM
2.5) and gaseous pollutants (NO
2) on the bike and motor driving routes in Cambridge and Colchester. The study designed experiments and data collection campaigns to understand the factors leading to air quality fluctuations in urban traffic routes. The resulting measurements show that NO
2 concentrations are higher in motor driving routes and in certain locations on the bike routes that are part of (or very close to) the motor route. The PM concentrations are generally higher near parks and open greenspaces but can be argued to be within the recommended limits. Finally, this paper proposes steps to improve the urban infrastructure to tackle emissions and spread awareness among the citizens.
Enhancing mammography: a comprehensive review of computer methods for improving image quality
Authors: Santos Joana Cristo , Santos Miriam Seoane , Abreu Pedro Henriques
Published: September 2024

Mammography imaging remains the gold standard for breast cancer detection and diagnosis, but challenges in image quality can lead to misdiagnosis, increased radiation exposure, and higher healthcare costs. This comprehensive review evaluates traditional and machine learning-based techniques for improving mammography image quality, aiming to benefit clinicians and enhance diagnostic accuracy. Our literature search, spanning 2015 – 2024, identified 115 articles focusing on contrast enhancement and noise reduction methods, including histogram equalization, filtering, unsharp masking, fuzzy logic, transform-based techniques, and advanced machine learning approaches. Machine learning, particularly architectures integrating denoising autoencoders with convolutional neural networks, emerged as highly effective in enhancing image quality without compromising detail. The discussion highlights the success of these techniques in improving mammography images’ visual quality. However, challenges such as high noise ratios, inconsistent evaluation metrics, and limited open-source datasets persist. Addressing these issues offers opportunities for future research to further advance mammography image enhancement methodologies.
Recent advances in design and preparation of micro diamond cutting tools
Authors: Liu Hanzhong , Yan Yongda , Cui Jiwen , Geng Yanquan , Sun Tao , Luo Xichun , Zong Wenjun
Published: September 2024

Micro diamond tools are indispensable for the efficient machining of microstructured surfaces. The precision in tool manufacturing and cutting performance directly determines the processing quality of components. The manufacturing of high-quality micro diamond tools relies on scientific design methods and appropriate processing techniques. However, there is currently a lack of systematic review on the design and manufacturing methods of micro diamond tools in academia. This study systematically summarizes and analyzes modern manufacturing methods for micro diamond tools, as well as the impact of tool waviness, sharpness, and durability on machining quality. Subsequently, a design method is proposed based on the theory of cutting edge strength distribution to enhance tool waviness, sharpness, and durability. Finally, this paper presents current technical challenges faced by micro diamond tools along with potential future solutions to guide scientists in this field. The aim of this review is to contribute to the further development of the current design and manufacturing processes for micro diamond cutting tools.
Comparison and analysis of properties of V-type HV-LSPMSM with non-magnetic and magnetic-wedges
Authors: Xie Qiuyue , Deng Qiuling , Ren Bing , Zhong Yichang , Ou Jinsheng
Published: September 2024

In order to improve the magnetic density distribution and torque ripple waveform of the motor and enhance its efficiency, the effect of slot wedge on motor performance is discussed in this paper. Taking 6 kV, 710 kW high-voltage line-start PMSM (HV-LSPMSM) as an example, the mathematical model is established, the influence mechanism of slot wedge on air gap density, loss, efficiency and torque ripple of motor is analyzed. The HV-LSPMSM prototype was manufactured, the deviations of several important motor parameters are less than 5% by comparing the test data and the finite element analysis (FEA) results, thus, the accuracy and reliability of the modified finite element model (FEM) are verified, it provides an experimental basis for further research on the effect of relative permeability variation on motor performance. The effects of nonmagnetic-wedges and magnetic-wedges on the motor’s performance are systematically compared. The research results show that compared with the non-magnetic wedges, the magnetic wedges are used to make the magnetic density more uniform, the eddy current loss with magnetic wedge (μ = 5) is reduced by 7.292 kW, and the motor efficiency is improved. The torque ripple rate with magnetic wedge (μ = 3) is reduced by 3.35%, and the torque waveform is significantly improved. And It is found that magnetic wedge (μ > 3) slowed down the iron loss reduction rate. The research provides an important theoretical and experimental basis for the design of HV-LSPMSM and the application of magnetic-wedge in motor.
Design and development of a low-cost hyperspectral imaging setup via a machine-learningbased approach
Authors: Meena Jyotisana , Unni Sujatha Narayanan
Published: September 2024

This article presents a potential solution for developing a low-cost hyperspectral imaging (HSI) setup by preserving pertinent information acquired from a conventional hyperspectral imaging setup. Conventional hyperspectral images (HSI) of three different types of leaves, gongura (Hibiscus sabdariffa), amaranthus (Amaranthus viridis), and banana (Musa acuminata) were acquired with 204 wavelengths/bands. The spectra are processed using linear discriminant analysis (LDA) to find a set of signature wavelengths for leaf classification. Afterwards, 20 visible range wavelengths (440 to 700 nm) were found to be incorporated into a low-cost setup involving a monochromator, beam steering elements, and a smartphone camera with associated machine learning (ML) classifiers. For building the datasets, we extracted 90 spectra from the images captured using the conventional HSI setup under the full spectra range (397 nm to 1003 nm). Similarly, 90 spectra were extracted from the images captured from the low-cost setup under the 20 signature wavelengths. For further experimentation, we split the datasets into Dataset-A, containing 70% of the total spectra, and the remaining 30% in Dataset-B for HSI as well as low-cost setup. Dataset- B was reserved to evaluate the robustness of the classifiers on an unseen dataset. LDA surpasses the other classifiers in leaves classification for HSI as well as low-cost setup. For the HSI setup, LDA achieved a 100% average score for performance matrices (classification accuracy, precision, Recall, and F1-score) on dataset A as well as on dataset B. Moreover, for the low-cost setup, LDA achieved 98.33% ± 4.99% classification accuracy, 98.89% ± 3.33% precision, 98.33% ± 4.99% recall, and 98.22% ± 5.33% F1-score on dataset A. Additionally, LDA achieved 96.29% classification accuracy, 96.67% precision, 96.29% recall, and 96.28% F1-score for dataset B. The promising results indicated that the low-cost set-up closely emulates the HSI system’s performance in terms of performance metrics, delivering a low-cost HSI system for various applications in the future.
Research progress on arc-based additive repair (AAR) technology for metal parts
Authors: Aimin Jiang , Abdullah Ahmad Baharuddin , Pramodkumar S K
Published: September 2024

Arc-based additive additive technology, like other additive manufacturing technologies such as laser cladding, cold spraying, has been used in repairing metal parts that suffer harsh working conditions, including wear, corrosion, and breaking which prevent them from realising an economic development route when lifespan is extended. However, there is a limitation in the existing study of arc-based additive repair technology. against the backdrop of the rapid development of many emerging technologies, such as artificial intelligence. Hence, this paper aims to provide a holistic status quo of arc-based additive repairing technology (AAR) which includes five sections: Firstly, AAR is overviewed and then followed by types of AAR that provide an understanding of explicit AAR technique, such as powder plasma arc welding, plasma-transfer arc welding, gas metal arc welding, and gas tungsten arc welding. Secondly, parameters optimization characteristics and performance improvement measures related to arc energy density, shielding gas flow rate, tool path, and additional energy field are presented. Thirdly, defects and enhancing methods, including inner gas porosity, distortion and deformation, and cracks and corresponding addressing approaches, are discussed. Finally, challenges like efficiency and complexity of processes, defect control and quality assurance, and process displacement and geometric accuracy are concluded, and trends of AAR are proposed. Through this review, a new picture of the current state of AAR research unfolds that expect to inspire a sight-clear future.
Shot peening effects on Cr-Mo-V steel: a comprehensive study of microstructure, surface roughness, residual stress, and mechanical behavior
Authors: Sarveswara Reddy S , Durga Rajesh K , Maiti A K , Janaki Durga Venkatesh
Published: September 2024

This study presents a comprehensive study of the microstructure, mechanical characteristics, and surface roughness of Cr-Mo-V low alloy steels and a detailed investigation of the overall impact of shot peening (SP). The microstructure was examined using the optical and scanning electron microscope, showing a significant grain size decrease after shot peening. Evaluations of mechanical characteristics, such as microhardness and tensile strength, showed a noteworthy rise, suggesting enhanced material strength. Studies using fragmentography shed more light on changed fracture tendencies. X-ray diffraction technique (XRD) was used to measure residual stress distribution, and the outcomes displayed an increase after SP, which suggests that internal stresses were created. Surface roughness measurements also showed a noticeable decline, indicating better surface quality. The transformational effects of shot peening on Cr-Mo-V low alloy steels were highlighted by comparative investigations with base metals, providing insights into enhancing material performance for various engineering applications.
Multi-UAV adaptive super-twisting integral terminal sliding mode formation control
Authors: Wang Jun , Luo Mingmin
Published: September 2024

This paper addresses issues such as model uncertainties, actuator failures, and gust disturbances in multi-quadrotor UAV formation flight. An adaptive super-twisting integral terminal sliding mode control method is proposed, incorporating a ‘Leader-Follower’ formation control strategy. The approach includes designing an adaptive super-twisting integral terminal sliding mode controller and a formation adaptive cooperative controller. Additionally, adaptive gains are utilized to manage the effects of actuator failures, gust disturbances, and ground station interference, ensuring safe formation flight. Simulation and experimental results indicate that the proposed controller can track the target trajectory within a finite time and effectively maintain formation flight.
Event-driven nearshore and shoreline coastline detection on SpiNNaker neuromorphic hardware
Authors: Fatahi Mazdak , Boulet Pierre , D’Angelo Giulia
Published: September 2024

Coastline detection is vital for coastal management, involving frequent observation and assessment to understand coastal dynamics and inform decisions on environmental protection. Continuous streaming of high-resolution images demands robust data processing and storage solutions to manage large datasets efficiently, posing challenges that require innovative solutions for real-time analysis and meaningful insights extraction. This work leverages low-latency event-based vision sensors coupled with neuromorphic hardware in an attempt to decrease a two-fold challenge, reducing the computational burden to ∼0.375 mW whilst obtaining a coastline detection map in as little as 20 ms. The proposed Spiking Neural Network runs on the SpiNNaker neuromorphic platform using a total of 18 040 neurons reaching 98.33% accuracy. The model has been characterised and evaluated by computing the accuracy of Intersection over Union scores over the ground truth of a real-world coastline dataset across different time windows. The system’s robustness was further assessed by evaluating its ability to avoid coastline detection in non-coastline profiles and funny shapes, achieving a success rate of 97.3%.
The prime spectrum of the Drinfeld double of the Jordan plane
Authors: Brown K. , Stafford J.
Published: September 2024

The Hopf algebra

D

\mathcal {D}

which is the subject of this paper can be viewed as a Drinfeld double of the bosonisation of the Jordan plane. Its prime and primitive spectra are completely determined. As a corollary of this analysis it is shown that

D

\mathcal {D}

satisfies the Dixmier-Moeglin Equivalence, leading to the formulation of a conjecture on the validity of this equivalence for pointed Noetherian Hopf algebras.
Modular properties of elliptic algebras
Authors: Chirvasitu Alex , Kanda Ryo , Smith S.
Published: September 2024

Fix a pair of relatively prime integers

n
>
k
≥
1

n>k\ge 1

, and a point

(
η

|

τ
)
∈

C

×

H

(\eta \,|\,\tau )\in \mathbb {C}\times \mathbb {H}

, where

H

\mathbb {H}

denotes the upper-half complex plane, and let

(

a

b

c

d

)

∈

S
L

(
2
,

Z

)

{{a\;\,b}\choose {c\,\;d}}\in \mathrm {SL}(2,\mathbb {Z})

. We show that Feigin and Odesskii’s elliptic algebras

Q

n
,
k

(
η

|

τ
)

Q_{n,k}(\eta \,|\,\tau )

have the property
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper Q Subscript n comma k Baseline left-parenthesis StartFraction eta Over c tau plus d EndFraction vertical-bar StartFraction a tau plus b Over c tau plus d EndFraction right-parenthesis approximately-equals upper Q Subscript n comma k Baseline left-parenthesis eta vertical-bar tau right-parenthesis">

Q

n
,
k

(

η

c
τ
+
d

|

a
τ
+
b

c
τ
+
d

)

≅

Q

n
,
k

(
η

|

τ
)

Q_{n,k}\big (\frac {\eta }{c\tau +d}\,\big \vert \,\frac {a\tau +b}{c\tau +d}\big )\cong Q_{n,k}(\eta \,|\,\tau )

. As a consequence, given a pair

(
E
,
ξ
)

(E,\xi )

consisting of a complex elliptic curve

E
E

and a point

ξ
∈
E

\xi \in E

, one may unambiguously define

Q

n
,
k

(
E
,
ξ
)
≔

Q

n
,
k

(
η

|

τ
)

Q_{n,k}(E,\xi )≔Q_{n,k}(\eta \,|\,\tau )

where

τ
∈

H

\tau \in \mathbb {H}

is any point such that

C

/

Z

+

Z

τ
≅
E

\mathbb {C}/\mathbb {Z}+\mathbb {Z}\tau \cong E

and

η
∈

C

\eta \in \mathbb {C}

is any point whose image in

E
E

is

ξ
\xi

. This justifies Feigin and Odesskii’s notation

Q

n
,
k

(
E
,
ξ
)

Q_{n,k}(E,\xi )

for their algebras. The algebras

Q

n
,
1

(
η

|

τ
)

Q_{n,1}(\eta \,|\,\tau )

are commonly known as Sklyanin algebras in honor of Sklyanin’s discovery of

Q

4
,
1

(
η

|

τ
)

Q_{4,1}(\eta \,|\,\tau )

.
Bacillus subtilis grown in a “breathing” vessel without sparger aeration
Authors: Yoshida Ken-ichi , Yokoyama Kyosuke , Öktem Ayşegül , Ishikawa Shu , van Dijl Jan Maarten , Yotsuya Masato , Sato Ryosuke
Published: September 2024

Here we present a “breathing” vessel consisting of expanded polytetrafluoroethylene, which allows gas exchange but no liquid permeation. The bacterial culture inside needs only agitation to promote air supply. Using this setup, a Bacillus subtilis cell factory for scyllo-inositol production grew to produce scyllo-inositol efficiently. The results indicate that our approach represents a sustainable “greener” approach for the cell factory.
Impact of structured multicentre enhanced recovery after surgery (ERAS) protocol implementation on length of stay after colorectal surgery
Authors: Bayat Zubair , Govindarajan Anand , Victor J Charles , Kennedy Erin D
Published: September 2024

Background

Increased length of stay after surgery is associated with increased healthcare utilization and adverse patient outcomes. While enhanced recovery after surgery (ERAS) protocols have been shown to reduce length of stay after colorectal surgery in trial settings, their effectiveness in real-world settings is more uncertain. The aim of this study was to assess the impact of ERAS protocol implementation on length of stay after colorectal surgery, using real-world data.

Methods

In 2012, ERAS protocols were introduced at 15 Ontario hospitals as part of the iERAS study. A cohort of patients undergoing colorectal surgery treated at these hospitals between 2008 and 2019 was created using health administrative data. Mean length of stay was computed for the intervals before and after ERAS implementation. Interrupted time series analyses were performed for predefined subgroups, namely all colorectal surgery, colorectal surgery without complications, right-sided colorectal surgery, and left-sided colorectal surgery. Sensitivity analyses were then conducted using adjusted length of stay, accounting for length of stay predictors, including: patient age, sex, marginalization, co-morbidities, and diagnosis; surgeon volume of cases, years in practice, and colorectal surgery expertise; hospital volume; and other contextual factors, including procedure type and timing, surgical approach, and in-hospital complications.

Results

A total of 32 612 patients underwent colorectal surgery during the study interval. ERAS implementation led to a decrease in length of stay of 1.05 days (13.7%). Larger decreases in length of stay were seen with more complex surgeries, with a level change of 1.17 days (15.6%) noted for the subgroup of patients undergoing left-sided colorectal surgery. The observed decreases in length of stay were durable for the length of the study interval in all analyses. When adjusting for predictors of length of stay, the effect of ERAS implementation on length of stay was larger (reduction of 1.46 days).

Conclusion

Introducing formal ERAS protocols reduces length of stay after colorectal surgery significantly, independent of temporal trends toward decreasing length of stay. These effects are durable, demonstrating that ERAS protocol implementation is an effective hospital-level intervention to reduce length of stay after colorectal surgery.
Incidence and Risk Factors for Invasive Fungal Infections in Patients Initiating Tumor Necrosis Factor–Alpha Inhibitors for Inflammatory Bowel Disease and Rheumatoid Arthritis
Authors: Hennessee Ian , Benedict Kaitlin , Bahr Nathan C , Lipner Shari R , Gold Jeremy A W
Published: September 2024

In a commercial claims database analysis, <0.5% of patients with inflammatory bowel disease or rheumatoid arthritis developed an invasive fungal infection (IFI) within 1 year of initiating tumor necrosis factor–alpha therapy. Histoplasmosis was the most common IFI type. Overall IFI incidence varied based on region, underlying conditions, and use of certain immunosuppressive medications.
Epigenetic transgenerational inheritance of toxicant exposure-specific non-coding RNA in sperm
Authors: McSwiggin Hayden , Magalhães Rubens , Nilsson Eric E , Yan Wei , Skinner Michael K
Published: September 2024

Environmentally induced epigenetic transgenerational inheritance of phenotypic variation and disease susceptibility requires the germ cell (sperm or egg) transmission of integrated epigenetic mechanisms involving DNA methylation, histone modifications, and non-coding RNA (ncRNA) actions. Previous studies have demonstrated that transgenerational exposure and disease-specific differential DNA methylation regions (DMRs) in sperm are observed and that ncRNA-mediated DNA methylation occurs. The current study was designed to determine if transgenerational exposure-specific ncRNAs exist in sperm. Specifically, toxicants with distinct mechanisms of action including the fungicide vinclozolin (anti-androgenic), pesticide dichlorodiphenyltrichloroethane (estrogenic), herbicide atrazine (endocrine disruptor at cyclic adenosine monophosphate level), and hydrocarbon mixture jet fuel (JP8) (aryl hydrocarbon receptor disruptor) were used to promote transgenerational disease phenotypes in F3 generation outbred rats. New aliquots of sperm, previously collected and used for DNA methylation analyses, were used in the current study for ncRNA sequencing analyses of nuclear RNA. Significant changes in transgenerational sperm ncRNA were observed for each transgenerational exposure lineage. The majority of ncRNA was small noncoding RNAs including piwi-interacting RNA, tRNA-derived small RNAs, microRNAs, rRNA-derived small RNA, as well as long ncRNAs. Although there was some overlap among the different classes of ncRNA across the different exposures, the majority of differentially expressed ncRNAs were exposure-specific with no overlapping ncRNA between the four different exposure lineages in the transgenerational F3 generation sperm nuclear ncRNAs. The ncRNA chromosomal locations and gene associations were identified for a small number of differential expressed ncRNA. Interestingly, an overlap analysis between the transgenerational sperm DMRs and ncRNA chromosomal locations demonstrated small populations of overlapping ncRNA, but a large population of non-overlapping ncRNAs. Observations suggest that transgenerational sperm ncRNAs have both exposure-specific populations within the different classes of ncRNA, as well as some common populations of ncRNAs among the different exposures. The lack of co-localization of many of the ncRNAs with previously identified transgenerational DMRs suggests a distal integration of the different epigenetic mechanisms. The potential use of ncRNA analyses for transgenerational toxicant exposure assessment appears feasible.
Pulmonary embolism due to an intracardiac thrombosis in a patient affected by Behçet’s disease: a case report
Authors: Ambrosino Valeria , De Marco Francesca , Valli Gabriele , Ruggieri Maria Pia , Morelli Sergio
Published: September 2024

Background

Behçet’s disease is an inflammatory condition, caused by vasculitis of big and small veins and arteries in which, although vascular inflammation is the basis of disease, cardiac involvement is rare. We present a rare case of a man, affected by Behçet’s disease, with pulmonary embolism due to a floating thrombus in the right ventricle.

Case summary

We report a case of a 36-year-old man admitted to emergency department due to dyspnoea and haemoptysis. He had already been diagnosed with Behçet’s disease, and he was in therapy with low doses of azathioprine and prednisone from three months. Thorax CT scan detected pulmonary embolism with pulmonary infraction. No evidence of deep vein thrombosis was found. The echocardiogram pointed out a floating mass of at least 30 mm in the right ventricle. Cardiac magnetic resonance confirmed the diagnosis of right ventricle thrombosis. On the hypothesis of an inflammatory genesis of the thrombosis, immunosuppressive drugs and anticoagulation with vitamin K antagonist were prescribed. The patient underwent echocardiograms every 3 weeks, and the mass disappeared 5 months later.

Discussion

Behçet’s disease is a systemic inflammatory disorder that often affects vessels and rarely the heart. Thrombosis can be the only clinical feature of primary or relapsing events with also atypical origin site. Thrombosis suggests a high inflammatory status that needs to be balanced with the right immunosuppressive therapy, associated to anticoagulation.
Single-species quotas drive discards by multi-species trawlers in the Celtic Seas ecoregion when their relative abundance fluctuates
Authors: Browne Maria , Calderwood Julia , Brophy Deirdre , Minto Cóilín
Published: September 2024

Our study investigated discarding patterns by bottom otter trawlers over 17 years prior to the full implementation of the Landing Obligation. A generalized additive modelling approach was applied to at-sea sampling data to examine the most important drivers of the discards per unit effort (DPUE) of cod, whiting, hake, and haddock in the Celtic Seas ecoregion from 2002 to 2018. Many operational, environmental, regulatory, and spatio-temporal factors were tested. Fish above and below the minimum conservation reference size (MCRS) were modelled separately to compare drivers of discarding of these categories of unwanted catch. In the full time period analysis, the three most important factors in determining DPUE were geographic location, an interaction between geographic location and year, and year interacting with month. Further analysis of a subset of the time series indicated that quota availability significantly impacted the DPUE for <MCRS haddock, MCRS hake, while the quota allocated for one species often significantly influenced the DPUE of other species and size classes. Quota interacting with abundance had a significant impact for all >MCRS species and <MCRS hake. This indicates that changes in relative abundance compound discarding under quota constraints. Collectively, these results empirically demonstrate that single-species quotas majorly contribute to discards in a mixed-fisheries context.
Risky Business: Predator Chemical Cues Mediate Morphological Changes in Freshwater Snails
Authors: Wagner M J , Moore P A
Published: September 2024

Synopsis

Many prey organisms respond to the nonconsumptive effects of predators by altering their physiology, morphology, and behavior. These inducible defenses can create refuges for prey by decreasing the likelihood of consumption by predators. Some prey, as in marine mollusks, have been shown to alter their morphology in response to the presence of size-limited predation. To extend this work, we exposed pointed campeloma snails (Campeloma decisum) to chemical cues from a natural predator, the rusty crayfish (Faxonius rusticus), to better understand how snail morphology changes under the threat of predation. The total force needed to crush shells, total shell length, aperture width, and total weight, along with changes to these 3 body measurements, were recorded for each individual and used to quantify morphological changes as a function of risk. Snails exposed to crayfish chemical cues had shells that required significantly more force to crush their shells than controls (P = 0.023). Total shell length was greater in crayfish-exposed snails than in control snails (P = 0.012), and snails in the crayfish treatment also showed significantly more change in shell length than control snails (P = 0.007). Similarly, aperture width was significantly greater in exposed snails (P = 0.011). However, exposed snails exhibited significantly less change in aperture width than controls (P = 0.03). Finally, we found that snails exposed to crayfish weighed significantly more than snails in the control (P = 0.008). Thus, the results of this study show that morphology of gastropods is altered in the presence of predators, and this may be an antipredator tactic directly related to predation risk.