bluuebunny/crossref_metadata_2025 huggingface dataset:
Leveraging industry 4.0 techniques for predictive equipment maintenance: From concept to commissioning
Authors: Bondin Andrea , Zammit Joseph Paul
Published: August 2024

In recent decades, lean manufacturing has significantly impacted the manufacturing industry, gaining widespread adoption. Companies have increasingly recognised the competitive advantages of implementing flow-oriented production layouts, demand-flow technologies, and just-in-time production. This shift has also transformed the approach to maintenance, moving away from reactive strategies. With production cells becoming more susceptible to system disturbances, maintenance managers are now focused on strategic maintenance development to ensure reliable production equipment. The emergence of Industry 4.0 technologies has further reshaped plant maintenance, providing companies with accurate and dependable tools for proactive maintenance. This paper proposes a hypothesis of research conducted at the University of Malta, focusing on the potential application of predictive maintenance (PdM) in the upkeep of automation machinery. It suggests the use of a novel data management and acquisition system, grounded in simulation and deep learning modelling, to predict the remaining useful life (RUL) of machinery early during the design machine realisation. This exploration lays the groundwork for potential development of a comprehensive maintenance tool. Such a tool would optimise automation designs, estimate maintenance costs throughout the machine’s lifecycle, and prevent machine breakdown through proactive interventions.
Professionelle Gesundheitskompetenz von Hausärzt:innen – Ergebnisse
des HLS-PROF
Authors: Schaeffer Doris , Griese Lennert , Haarmann Alexander
Published: August 2024

Ziel Bisher existieren nur wenige Studien zur Gesundheitskompetenz (GK)
der Gesundheitsprofessionen. Wurde sie untersucht, stand die persönliche, nicht
die professionelle GK im Vordergrund. Deshalb wurde in einem
Dreiländerkonsortium ein neues Konzept und ein darauf basierendes
Erhebungsinstrument erarbeitet. Ziel des Beitrags ist es, auf der Basis damit
erhobenen Daten, die professionelle GK von Ärzt:innen zu untersuchen.

Methode Das genutzte Messinstrument besteht aus 34 Items und misst die
subjektiven Schwierigkeiten in vier bei der Förderung der GK von Patient:innen
zu bewältigenden Aufgabenbereichen: „Informations- und Wissensmanagement“,
„Informations- und Wissensvermittlung“, „Patientenzentrierte Kommunikation“,
„Professionelle digitale GK“. Im Sommer 2022 wurden 297 Allgemeinärzt:innen und
hausärztlich tätige Internist:innen online zu ihrer professionellen GK befragt.
Die professionelle GK (Punktwert 0–100) wurde deskriptiv sowie im Zusammenhang
mit dem Geschlecht, und ausgewählten berufsbezogenen und organisatorischen
Merkmalen mittels multipler linearer Regression untersucht.

Ergebnisse Die Befragten erreichen je nach Aufgabenbereich rund die Hälfte
bis knapp drei Viertel der möglichen Punktzahl. Der Aufgabenbereich
„Patientenzentrierte Kommunikation“ wird am einfachsten eingeschätzt, gefolgt
vom „Informations- und Wissensmanagement“ und der „Informations- und
Wissensvermittlung“. Am schwierigsten fällt der Bereich „Professionelle digitale
GK“. In der multivariaten Analyse steht die professionelle GK mit dem
Geschlecht, den organisatorischen Rahmen- und Ausbildungsbedingungen, der
Berufsdauer und dem Zurechtkommen mit der digitalen Informationsvielfalt in
Zusammenhang, wobei der Zusammenhang nach Aufgabenbereich variiert und zum Teil
eher schwach ausgeprägt ist.

Schlussfolgerung Die Ergebnisse zeigen wie wichtig es ist, die
professionelle GK von Ärzt:innen zu fördern und liefern zugleich Hinweise
darauf, wo dabei anzusetzen ist. Zudem legen sie nahe, die multivariaten
Regressionsmodelle um andere Determinanten zu erweitern, da die einbezogenen
Variablen teilweise nur wenig Varianz erklären.
Rhytidectomy Incision Techniques and Scar Outcomes: A Scoping Review
Authors: Liu Katherine Y. , Chou David W. , Verma Hannah , Sehgal Gavneet , Gregory Jill K. , Gidumal Sunder , Husain Solomon , Kontis Theda C. , Abraham Manoj T.
Published: August 2024

Although scar outcomes in rhytidectomy are crucial to patients and surgeons alike, there is a lack of consensus on incision techniques for optimizing rhytidectomy scars. A comprehensive scoping review of the literature was performed on rhytidectomy incision techniques and associated scar outcomes.

The PRISMA protocol was utilized to conduct a scoping review of the literature through MEDLINE, EMBASE, and Science Citation Index databases to identify articles discussing rhytidectomy incision techniques and scar outcomes.

A total of 49 studies were included in this scoping review. Four themes were identified related to rhytidectomy scars within these studies: temporal incision placement, tragal incision placement, lobule management, and postauricular incision design. Techniques within each theme were described and reported scar outcomes summarized.

There are many approaches to rhytidectomy incisions described in the literature, with reportedly low rates of scar complications for each of the techniques described. It cannot be elucidated which techniques are superior due to the heterogeneity of outcomes reported in the literature with significant variability in outcome measures, study design, and follow-up time. Future studies should focus on utilizing a standardized rating system to aid in objective determination of the superiority of one technique versus another.

Level of Evidence: Level I
More than a Drop in the Bucket
Authors: Ikenson Ben
Published: August 2024

Pressure fluctuation-based method promises precise, cost-effective microdroplet management.
Thermal optimization of a high heat load liquid-metal-bath cooled mirror at the Hefei Advanced Light Facility
Authors: Lin Minghao , Chen Jie , Wang Zimeng , Jiang Shuaikang , Wang Qiuping , Du Xuewei
Published: August 2024

Within the beamlines of diffraction-limited storage rings, the liquid-metal-bath cooling scheme is a prevalent choice for the cooling of high-heat load mirrors. This study employs the finite element analysis method to evaluate the thermal deformations of liquid-metal-bath horizontally deflecting mirrors in the Hefei Advanced Light Facility. In particular, we introduce a novel optimization strategy to obtain the optimal thermal deformation scenario, which also satisfies mechanical design requirements. Moreover, a concurrent optimization approach across multiple structural parameters of mirrors is adopted to attain globally optimal thermal deformation. Following the optimization of the mirror’s structural parameters, the curvature radius increases to 227 km, while the residual slope error decreases to 36.3 nrad at 6 eV in the meridian direction. The ray tracing analysis of the beam demonstrates a considerable reduction in the influence of thermal deformation on the beam’s focal point. This work proposes an optimization method for designing cooling schemes under mechanical constraints.
Numerical simulation of the influence of wave parameters on the horizontal cylinder in the nonlinear coupling of the wave–current
Authors: Guo Chunyu , Ji Minglei , Han Yang , Wu Yanyuan , Wang Yonghao
Published: August 2024

Considering that marine structures are frequently subjected to the combined effects of waves and currents, the wave–current coupling environment largely determines the structural load and the surrounding water–air mixed flow, which is a typical feature of offshore structures, such as ships and offshore platforms. This study focuses on the interaction between a horizontal cylinder and a free surface in a wave–current nonlinear coupled environment using numerical simulations. The numerical method is based on the incompressible Navier–Stokes equation, with the volume-of-fluid method used to capture the free surface. Based on the second-order Stokes wave theory, we studied the impact of wave height and steepness on the cylinder force, vorticity field, free-surface deformation, and spatial–temporal distribution characteristics of entrainment bubbles. The results showed that the wave height and wave steepness have opposite effects on the root mean square (RMS) value of the force and influence the amplitude and period of the force curve. The stretching of the negative vortex led to varying degrees of double-frequency oscillation modes in the force curves. The main sources of bubbles in the wake are the breaking of the free surface and the entrainment caused by the cylinder vortex, and the bubbles caused by the former account for the majority. Compared with the wave height, an increase in wave steepness can cause a more severe interface breaking, resulting in more entrainment bubbles.
Effectiveness of respiratory protective equipment in reducing inhalation and contact exposure risks of dental workers during ultrasonic scaling
Authors: Cao Shicheng , Jia Zhongjian , Xing Chaojie , Ai Zhengtao
Published: August 2024

The high-concentration droplets produced from ultrasonic scaling treatments may carry many pathogens. The close contact between dental workers and patients significantly amplifies their exposure risk to these droplets. Although various types of respiratory protective equipment (RPE) are utilized by dental workers during treatments, their effectiveness in reducing the risks associated with inhalation and contact exposure remains uncertain. In this study, computational fluid dynamics technology was employed to investigate the impact of RPE type, surgery duration, air changes per hour (ACH), and air distribution on the risks related to inhalation and deposition exposure. The results revealed that wearing masks considerably reduced the risk of inhalation exposure for dental workers, with a decrease in inhalation fractions from 25.3 ppm (without RPE) to 1.3–4.5 ppm (with RPE). Combining blue surgical masks and face shields decreased the risk of inhalation fraction by 5% compared to wearing no RPE. Notably, there was over 60% of spray droplets landed on the patient's head; however, only approximately 5%, 6%, 8%, and 3% were deposited on the patient's body, doctor's body, floor, and dental chair, respectively. Increasing ventilation from 3 to 9 ACH decreased dental workers' inhalation fraction by 9.8 ppm. Type III (with the inlet and outlet at opposite walls) decreased the suspension fraction by 4.3% compared with Type II (with the inlet and outlet at the same wall) while achieving a near-zero inhalation fraction of dental workers. These findings offer valuable insights for mitigating cross-infection risks between dental workers and patients in dental clinics.
Exploring the tendency of Brownian agglomeration in polydispersed systems of solid atmospheric aerosols
Authors: Osaci Mihaela , Cacciola Matteo , Gheorghe Lavinia
Published: August 2024

Recent extensive research has focused on atmospheric aerosol systems, driven by their far-reaching implications for climate and public health, with a goal to identify optimal air quality management practices. This study employs Langevin dynamics to investigate the impact of size distribution and concentration of submicrometer solid aerosol particles on Brownian agglomeration tendencies within an isothermal, hydrostatically balanced atmosphere. To accomplish this, a Langevin dynamic model is devised, and parameters are carefully determined to ensure numerical integration precision, stability, and efficiency. Using this model, we numerically simulate the average agglomeration nucleus and overall agglomeration rate within the system while considering variations in the standard deviation of size distribution and volume fraction of aerosol particles.
Enhanced light confinement in nonlocal resonant metasurfaces with weak multipolar scatterers
Authors: Romero Amanda , Babicheva Viktoriia E.
Published: August 2024

Stronger light confinement can be enabled by nanoantennas in the nanostructure and result in efficient control of the directionality of the scattering. We report on an observation of the well-pronounced multipolar resonances from nickel nanoantennas originating from collective effects. We show that the collective coupling of multipolar modes from weak scatterers can substantially enhance the electric dipole and quadrupole resonances. We also demonstrate the generalized lattice Kerker effect in this nanoantenna array. Resonant multipolar excitations within nickel nanoantenna arrays can significantly enhance phenomena such as magneto-optical effects, indicating promising potential for advanced applications in the field of nanophotonics and sensing.
Inertial migration of rigid particles in shear-thinning fluids under asymmetric wall slip conditions
Authors: Krishnaram K. K. , Chandran K. Nandakumar , Ha Man Yeong , Kumar Ranjith S.
Published: August 2024

The determination of flow-induced equilibrium positions in pressure-driven flows in microchannels is of great practical importance in particle manipulation. In the computational analysis presented in this paper, the inertial ordering of neutrally buoyant rigid spheres in shear-thinning fluid flow through a hydrophobic microchannel is investigated. The combined effect of the viscosity index n of a power-law fluid and fluid slippage at the wall on the lateral focusing of microspheres is examined in detail. Using the finite element method, the Eulerian flow field between partially slipping parallel walls is simulated, and the Lagrangian movement of particles is continuously tracked. The Navier slip model is used to ensure a finite fluid velocity at the wall, and it is tuned by modifying the slip-length. It is observed that inertial particles concentrate at a standard equilibrium position of 0.6 times the channel half-width H, irrespective of fluid slip due to the symmetry of the flow field. However, this equilibrium position shifts closer to the walls as the viscosity index increases; for instance, when n = 0.5, particles stabilize at 0.75H. As a consequence of asymmetry in hydrodynamic behavior due to different fluid slippages at the upper and lower walls, the particle migration path is altered. In a channel with a no-slip upper wall and a partially slipping lower wall (β/H = 0.4), particles settle closer to the lower wall at 0.8H. Most importantly, the lateral movement of a particle released at a given vertical position can be altered by tailoring the wall hydrophobicity and viscosity index, thus enabling multiple equilibrium locations to be achieved.
Particle–droplet coalescence and jumping on superhydrophobic surfaces—A direct numerical simulations study
Authors: Konstantinidis K. , Göhl J. , Mark A. , Yan X. , Miljkovic N. , Sasic S.
Published: August 2024

We report here multiphase direct numerical simulations of a recently discovered passive mechanism of self-cleaning on superhydrophobic surfaces. The removal of contaminants is governed by coalescence of a single droplet with a particle of micrometer size, where the droplet initiates spontaneous spreading on the particle and drives particle–droplet jumping. We use an in-house volume of fluid–immersed boundary numerical framework, introduce and thoroughly analyze capillary forces at the particle–droplet contact line, and validate our simulations in relation to previous experimental results. We then perform a comprehensive investigation over a number of different parameters regarding the interaction physics of the droplet with the particle and the substrate. We systematically vary particle, droplet, and surface physical and wetting properties and unveil a range of scenarios related to different energy dissipation mechanisms as a function of the substrate contact angles and contact-angle hysteresis. Detailed parameter studies establish the connection between the droplet, substrate and particle properties, and the outcome and efficiency of the particle-launching process. We particularly highlight the effects of the particle–droplet size ratio and the wettability of the particle. We reveal and discuss the corresponding dissipation mechanisms and quantify the energy efficiencies of the jumping process in the treated parameter space.
Effects of fish body thickness on hydrodynamic performance for self-propulsion carangiform swimmer
Authors: Xiong Zhongying , Xia Huan , Han Tao
Published: August 2024

The efficient swimming of fish is closely linked to their unique body morphology. This study seeks to explore the impact of body morphology on hydrodynamic performance through numerical analysis. Initially, the investigation focuses on carangiform swimmers with varying thicknesses, denoted by the thickness coefficient ψ. Key performance indicators such as vortices, velocity, pressure, thrust, and energy consumption are analyzed. The findings reveal a notable phenomenon of vortex deflection in self-propelled studies, which is affected by the interplay between initial vortices and flow conditions. Specifically, the carangiform swimmer with ψ = 1.4 exhibits the highest thrust but also the greatest energy consumption. In contrast, the swimmer with ψ = 0.8 demonstrates the best acceleration and steady swimming speeds with moderate energy usage. This paper provides new insights into how body morphology influences self-propulsion in aquatic environments.
An initial value insensitive constrained linear predictive evolution algorithm for gas–liquid phase equilibrium calculation problems
Authors: Tong Wangyu , Xiong Wentao , Zhan Yaqian
Published: August 2024

Heuristic algorithms are gradually becoming a type of new promising methods for solving phase equilibrium calculation problems since they do not have to calculate an initial value in advance like traditional methods such as direct Newton's method and indirect thermodynamic method. A new heuristic optimizer, constrained linear prediction evolution algorithm (CLPE) for phase equilibrium calculation under given volume, temperature, and moles (NVT-flash) is proposed in this paper. CLPE employs the total Helmholtz free energy of the NVT-flash problem as its objective function and employs the volume and moles vector of a certain phase as decision variables. Numerical experiments are conducted on four NVT-flash problems. The consistency between the experimental results and those obtained by some traditional methods verifies that the proposed CLPE is effective. The comparative advantage in computational overhead over the similar algorithms indicates the significance of this study. The success of CLPE can drive more heuristic algorithms to solve NVT-flash problems more efficiently, so as to advance the field of phase equilibrium calculation.
Parallel superposition of small-amplitude oscillatory shear flow upon steady shear flow from rotarance theory
Authors: Pak Myong Chol , Giacomin A. J.
Published: August 2024

The power of a macromolecular theory for the transport properties of a polymeric liquid increases with the number of analytical expressions for its most important material functions. In this work, we add another of these canonical function to our recent series of material function derivations for rotarance theory. By rotarance theory, we mean the explanation of the elasticity of polymeric liquids by use of (i) the diffusion equation to get the orientation distribution in Euler coordinates, and (ii) the integration in phase space using this distribution to get the target material function. In this paper, we target parallel superposition of oscillatory shear flow upon steady shear flow. We arrive at analytical expressions for both parts of the complex viscosity in parallel superposition. We find that these explain the classic experimental observations in parallel superposition: (a) the maximum in the real part of the complex viscosity, and (b) the negative values of minus its imaginary part, and (c) the independence of the steady mean shear stress from the superposed oscillation.
SlCPK27 cross-links SlHY5 and SlPIF4 in brassinosteroid-dependent photo- and thermo-morphogenesis in tomato
Authors: Zhu Changan , Hu Zhangjian , Hu Chaoyi , Ma Hongxue , Zhou Jie , Xia Xiaojian , Shi Kai , Foyer Christine H. , Yu Jingquan , Zhou Yanhong
Published: August 2024

ELONGATED HYPOCOTOYL5 (HY5) and PHYTOCHROME INTERACTING FACTORs (PIFs) are two types of important light-related regulators of plant growth, however, their interplay remains elusive. Here, we report that the activated tomato (
Solanum lycopersicum
) HY5 (SlHY5) triggers the transcription of a Calcium-dependent Protein Kinase
SlCPK27
. SlCPK27 interacts with and phosphorylates SlPIF4 at Ser-252 and Ser-308 phosphosites to promote its degradation. SlPIF4 promotes hypocotyl elongation mainly by activating the transcription of
SlDWF
, a key gene in brassinosteroid (BR) biosynthesis. Such a SlHY5-SlCPK27-SlPIF4-BR cascade not only plays a crucial role in photomorphogenesis but also regulates thermomorphogenesis. Our results uncover a previously unidentified mechanism that integrates Ca
2+
signaling with the light signaling pathways to regulate plant growth by modulating BR biosynthesis in response to changes in ambient light and temperature.
Orientation-independent-DIC imaging reveals that a transient rise in depletion attraction contributes to mitotic chromosome condensation
Authors: Iida Shiori , Ide Satoru , Tamura Sachiko , Sasai Masaki , Tani Tomomi , Goto Tatsuhiko , Shribak Michael , Maeshima Kazuhiro
Published: August 2024

Genomic information must be faithfully transmitted into two daughter cells during mitosis. To ensure the transmission process, interphase chromatin is further condensed into mitotic chromosomes. Although protein factors like condensins and topoisomerase IIα are involved in the assembly of mitotic chromosomes, the physical bases of the condensation process remain unclear. Depletion attraction/macromolecular crowding, an effective attractive force that arises between large structures in crowded environments around chromosomes, may contribute to the condensation process. To approach this issue, we investigated the “chromosome milieu” during mitosis of living human cells using an orientation-independent-differential interference contrast module combined with a confocal laser scanning microscope, which is capable of precisely mapping optical path differences and estimating molecular densities. We found that the molecular density surrounding chromosomes increased with the progression from prophase to anaphase, concurring with chromosome condensation. However, the molecular density went down in telophase, when chromosome decondensation began. Changes in the molecular density around chromosomes by hypotonic or hypertonic treatment consistently altered the condensation levels of chromosomes. In vitro, native chromatin was converted into liquid droplets of chromatin in the presence of cations and a macromolecular crowder. Additional crowder made the chromatin droplets stiffer and more solid-like. These results suggest that a transient rise in depletion attraction, likely triggered by the relocation of macromolecules (proteins, RNAs, and others) via nuclear envelope breakdown and by a subsequent decrease in cell volumes, contributes to mitotic chromosome condensation, shedding light on a different aspect of the condensation mechanism in living human cells.
Label-free characterization of pathological changes in the portal area of liver fibrosis tissue using multiphoton imaging and quantitative image analysis
Authors: Zhang Xiong , Lian Yuan-E , Yu XunBin , Huang Xingxin , Zhang Zheng , Zhang Jingyi , Chen Jianxin , Li Lianhuang , Bai Yannan
Published: August 2024

Liver fibrosis plays a crucial role in the progression of liver diseases and serves as a pivotal stage leading to the development of liver cirrhosis and cancer. It typically initiates from portal area with various pathological characteristics. In this article, we employed multiphoton microscopy (MPM) to characterize the pathological changes in the portal areas of liver fibrosis tissues, and subsequently, we used our developed image analysis method to extract eight collagen morphological features from MPM images and also combined a deep learning method with a cell nuclear feature extraction algorithm to perform automatic nuclei segmentation and quantitative analysis in the H&E-stained histopathology images of portal areas. Our results demonstrate that MPM can effectively identify various pathological features in portal areas, and there are significant differences in four collagen features (collagen proportionate area, number, length and width) between normal and abnormal portal areas and in four nuclear features (mean ratio of axial length, disorder of distance to 3, 5 and 7 nearest neighbors) between normal portal area, bile duct hyperplasia and periductal fibrosis. Therefore, a combination of MPM and image-based quantitative analysis may be considered as a rapid and effective means to monitor histopathological changes in portal area and offer new insights into liver fibrosis.
Combined effect of strain and intrinsic spin–orbit coupling on band gap engineering of GNRs: a first-principles study
Authors: Kumar Sandeep , Pratap Surender , Trivedi Ravi , Chakraborty Brahmananda
Published: August 2024

By employing first-principles calculations, we theoretically investigate the impact of uniaxial strain and intrinsic spin–orbit coupling (SOC) on the electronic properties of zigzag and armchair edge hydrogen (H)-passivated graphene nanoribbons (GNRs). We find that band structure and density of states of 4-zigzag graphene nanoribbon (ZGNR) and 15-armchair graphene nanoribbon (AGNR) are highly sensitive to the combined effect of strain and intrinsic SOC. In the case of H-passivated 4-ZGNR, SOC with a strain

>

10% increases the energy band by increasing spin-polarized states at the opposite edges. In contrast to 4-ZGNR, the oscillatory behavior of band gap of H-passivated 15-AGNR is preserved in the presence of strain and SOC. Moreover, for both types of GNRs (zigzag and armchair), the presence of strain and intrinsic SOC preserve spin symmetry.
Topological phases of tight-binding trimer lattice in the BDI symmetry class
Authors: Ghuneim Mohammad , Weda Bomantara Raditya
Published: August 2024

In this work, we theoretically study a modified Su-Schrieffer-Heeger (SSH) model in which each unit cell consists of three sites. Unlike existing extensions of the SSH model which are made by enlarging the periodicity of the (nearest-neighbor) hopping amplitudes, our modification is obtained by replacing the Pauli matrices in the system’s Hamiltonian by their higher dimensional counterparts. This, in turn, leads to the presence of next-nearest neighbor hopping terms and the emergence of different symmetries than those of other extended SSH models. Moreover, the system supports a number of edge states that are protected by a combination of particle-hole, time-reversal, and chiral symmetry. Finally, our system could be potentially realized in various experimental platforms including superconducting circuits as well as acoustic/optical waveguide arrays.
Controllable synthesis of porous boron nitride fibers modified by cobalt and nickel oxides for efficient ceftriaxone sodium adsorption from aqueous solution
Authors: Wang Dong , Yang Shaobo , Yan Song , Gu Yaxin , Fang Yi , Cao Chaochao , Tang Chengchun
Published: August 2024

Antibiotics can easily enter the water environment through direct or indirect approach, causing environmental pollution and endangering the health of organisms. Therefore, development of highly efficient adsorbent materials to adsorb and remove antibiotics is necessary. Here, cobalt oxide and nickel oxide are uniformly and tightly bonded on the surface of porous boron nitride fibers (PBNFs-NiCo), increasing the number of functional groups (B–O and N–H) and hydrogen bond receptors within PBNFs. The total pore volume and specific surface area of resulting PBNFs-NiCo can reach up to 0.48 cm3 g−1 and 720.3 m2 g−1, respectively. Encouraged by the unique micromorphology and chemical composition mentioned above, PBNFs-NiCo exhibits excellent ceftriaxone sodium (CS) adsorption ability, showing the adsorption capacity and removal efficiency up to 410.9 mg g−1 and 96.5%, respectively. Chemical adsorption plays an important role in their adsorption behavior, abiding by Langmuir adsorption theory and pseudo-second-order kinetic equation. Importantly, PBNFs-NiCo exhibits fascinating adsorption effects in surroundings with pH ranging from 4 to 6, 25 °C and varying salt concentrations. This work would establish a practical and feasible foundation for the practical application of PBNFs-NiCo for CS adsorption in aqueous solution.
Optimal pinwheel partitions for the Yamabe equation
Authors: Clapp Mónica , Faya Jorge , Saldaña Alberto
Published: August 2024

We establish the existence of an optimal partition for the Yamabe equation in

R

N

made up of mutually linearly isometric sets, each of them invariant under the action of a group of linear isometries. To do this, we establish the existence of a solution to a weakly coupled competitive Yamabe system, whose components are invariant under the action of the group, and each of them is obtained from the previous one by composing it with a linear isometry. We show that, as the coupling parameter goes to

−
∞

, the components of the solutions segregate and give rise to an optimal partition that has the properties mentioned above. Finally, taking advantage of the symmetries considered, we establish the existence of infinitely many sign-changing solutions for the Yamabe equation in

R

N

that are different from those previously found by Ding, and del Pino, Musso, Pacard and Pistoia.
A single-bubble source for gravitational waves in a cosmological phase transition
Authors: Blum Kfir , Mirbabayi Mehrdad
Published: August 2024

We show that quantum fluctuations of an expanding phase transition bubble give rise to gravitational wave (GW) emission, even when considering a single bubble, without bubble collisions or plasma effects. The ratio of GW energy to the total bubble energy reservoir increases with time as ∝ t. If the bubble expands for long enough before percolation destroys it, back-reaction due to the GW emission becomes important after t
br ~ (16π5)m
pl
2
R
0
3, where R
0 is the bubble nucleation radius and m
pl is the reduced Planck mass. As seen by experiments today, the GW energy spectrum would appear blue.
However, simple estimates suggest that the signal falls short of detection by even ambitious future experiments.
Prediction of plasma rotation velocity and ion temperature profiles in EAST Tokamak using artificial neural network models
Authors: Lin Zichao , Zhang Hongming , Wang Fudi , Bae Cheonho , Fu Jia , Shen Yongcai , Dai Shuyu , Jin Yifei , Lu Dian , Fu Shengyu , Ji Huajian , Lyu Bo
Published: August 2024

Artificial neural network models have been developed to predict rotation velocity and ion temperature profiles on the EAST tokamak based on spectral measurements from the x-ray crystal spectrometer. Both Deep Neural Network (DNN) and Convolutional Neural Network (CNN) models have been employed to infer line-integrated ion temperatures. The predicted results from these two models exhibit a strong correlation with the target values, providing an opportunity for cross-validation to enhance prediction accuracy. Notably, the computational speed of these models has been significantly increased, surpassing traditional methods by over tenfold. Furthermore, the investigation of input data range and error prediction serves as the foundation for future automated calculation process. Finally, CNNs have also been employed to predict line-integrated rotation velocity profiles and inverted ion temperature profiles for their robustness in the training process. It is noted that these algorithms are not restricted to any specific physics model and can be readily adapted to various fusion devices.
Influence of titanium carbide particles on the characteristics of microarc oxidation layer on Ti6Al4V alloy
Authors: Wei Leyu , Shao Yufei , Li Wenqiang , Feng Zaiqiang , Yan Zhenwei , Wang Feng , Li Ningning , Li Gang , Tang Mingqi
Published: August 2024

The Microarc Oxidation (MAO) layer on titanium alloy was mainly composed of TiO2, and there were some defects, such as holes and cracks, which made the performance of the MAO layer not ideal. To enhance the properties of the MAO layer, titanium carbide (TiC) particles were added to the electrolyte of a phosphate–silicate system as an additive. Consequently, the MAO layers containing the TiC phase on Ti6Al4V alloy were produced. The MAO process, composition, microstructure, and hardness of the MAO layer were comprehensively analyzed. Their frictional performance was assessed under reciprocating friction conditions without lubrication. The findings suggested that added TiC particles in the electrolyte played a significant role in creating the MAO layer, enhancing its thickness. The electrolyte without TiC particles produced an MAO layer primarily composed of TiO2 in two different mineral forms (rutile and anatase). Adding TiC particles resulted in the presence of TiC within the MAO layer, thereby facilitating the formation of a reinforced oxide layer. This addition also led to an improvement in the densification of the layer and a reduction in porosity. Notably, corrosion resistance testing indicated that incorporating 6 g l−1 TiC into the electrolyte resulted in superior performance compared with that obtained from the base electrolyte alone by achieving 1.4 times higher corrosion resistance. Moreover, a hardness value of 690 HV for the MAO layer was attained at a content level of 9 g l−1 TiC, demonstrating a significant 65% enhancement compared to the base oxide layer. This finding also demonstrated significantly enhanced friction property with a wear-volume reduction to 0.81 mm3. The findings on the relationship between the preparation of the MAO layer and its structure and properties can provide valuable guidance for designing and preparing the MAO layer.
Optical control of berry curvature in gated WSe2 bilayers
Authors: Rehman Majeed Ur , Rahman Zia Ur , Rahman Azizur , Ahmad Waqas , Ullah Sadeeq
Published: August 2024

Unlike single layers of 2H transition metal dichalcogenides (TMDCs), bilayers of 2H TMDCs maintain inversion and time reversal (TR) symmetries, resulting in a vanishing Berry curvature (

Ω
(
k
)
∼
0
)

that inhibits various potential transport phenomena. A nonzero Berry curvature

(
Ω
(
k
)
≠
0
)

is imperative for the occurrence of several unconventional transport phenomena, including the anomalous Hall effect and the anomalous Nernst effect. To overcome this limitation, we break these symmetries in bilayer TMDCs using electrostatic gating and circularly polarized light as external means. For non-gated WSe2 bilayers, circularly polarized light breaks TR symmetry, creating a finite Berry curvature signal in both conduction and valence bands, controllable by light intensity and its polarity. In gated WSe2 bilayers, where inversion symmetry is also broken, we observe a sign reversal in Berry curvature within the conduction bands, the extent of which depends on the relative strengths of the electric gating and light intensity. Overall, under finite bias and light intensity, the 2H bilayers of WSe2 exhibits finite spin Hall, valley Hall, and anomalous Hall conductivities, which depend on the strengths of the applied perturbations.
Effect of addition of Ce and accumulative roll bonding on structure-property of the Mg-Ce-Al hybrid composite and its prediction and comparison using artificial neural network (ANN) approach
Authors: Anne Gajanan , Bhat Nagaraj , H M Vishwanatha , S Ramesh , B H Maruthi Prashanth , Sharma Priyaranjan , S Aditya Kudva , Jagadeesh C , Nanjappa Yashwanth
Published: August 2024

Light alloys play a crucial role in realizing the national strategy for energy conservation and emission reduction, as well as promoting the upgrading of manufacturing industries. Mg/Al composite laminates combine the corrosion resistance and ductility of aluminium alloy with the lightweight characteristics of magnesium alloy. The addition of Ce (rare earth elements) can improve the mechanical properties of magnesium via grain refinement and improve the ductility of the hybrid composites. In the present work, an investigation on addition of Ce into the Mg/Al matrix through Accumulative Roll Bonding (ARB) has been presented. The Mg/Ce/Al hybrid composite consists of Mg-4%Zn alloy and Al 1100 alloy with 0.2% Ce particles added between the dissimilar layers. The changes occurred in the evaluation of microstructure, corrosion and mechanical properties of the Mg/Ce/Al hybrid composite as a result of deformation process and also the addition of Ce have been explicated. The ARB parameters: temperature, rolling speed, percentage reduction, and aging time, have been studied. An increase of about 2.36 times in strength and hardness of the hybrid composite, has been reported. Further, the structure–property relations in the Mg/Ce/Al hybrid composites were aslo predict and compare using machine learning models: Decision Tree and Multi-Layer Perceptron (MLP) models.
A CMOS front-end circuit for capacitive sensors with zero adjustment
Authors: Sun Fangxia , Tang Shoulong
Published: August 2024

A front-end circuit with measurement zero adjustment was designed using 180nm CMOS technology for capacitive sensors. A series-switched capacitor composed of capacitor under test and MOSFETs is controlled by a clock signal to convert capacitance to current. The minimum output current at fixed capacitance can be adjusted by applying different voltage to realize zero adjustment. The test shows that the output current has a monotonic linear relationship with the measured capacitance, with capacitance detection range reaches 50pF-3000pF and an output current range of 0.59mA-22.2mA. The maximum span of multiple measurements was lower than 8.37uA. The stable time is less than 23ms and sensitivity is 19.8uA/pF. This circuit is suitable for long-distance and wide-range capacitance detections.
Fitness-based growth of directed networks with hierarchy
Authors: Rodgers Niall , Tiňo Peter , Johnson Samuel
Published: August 2024

Growing attention has been brought to the fact that many real directed networks exhibit hierarchy and directionality as measured through techniques like trophic analysis and non-normality. We propose a simple growing network model where the probability of connecting to a node is defined by a preferential attachment mechanism based on degree and the difference in fitness between nodes. In particular, we show how mechanisms such as degree-based preferential attachment and node fitness interactions can lead to the emergence of the spectrum of hierarchy and directionality observed in real networks. In this work, we study various features of this model relating to network hierarchy, as measured by trophic analysis. This includes (I) how preferential attachment can lead to network hierarchy, (II) how scale-free degree distributions and network hierarchy can coexist, (III) the correlation between node fitness and trophic level, (IV) how the fitness parameters can predict trophic incoherence and how the trophic level difference distribution compares to the fitness difference distribution, (V) the relationship between trophic level and degree imbalance and the unique role of nodes at the ends of the fitness hierarchy and (VI) how fitness interactions and degree-based preferential attachment can interplay to generate networks of varying coherence and degree distribution. We also provide an example of the intuition this work enables in the analysis of a real historical network. This work provides insight into simple mechanisms which can give rise to hierarchy in directed networks and quantifies the usefulness and limitations of using trophic analysis as an analysis tool for real networks.
Transforming the bootstrap: using transformers to compute scattering amplitudes in planar

N

=
4

super Yang–Mills theory
Authors: Cai Tianji , Merz Garrett W , Charton François , Nolte Niklas , Wilhelm Matthias , Cranmer Kyle , Dixon Lance J
Published: August 2024

We pursue the use of deep learning methods to improve state-of-the-art computations in theoretical high-energy physics. Planar

N

=
4

Super Yang–Mills theory is a close cousin to the theory that describes Higgs boson production at the Large Hadron Collider; its scattering amplitudes are large mathematical expressions containing integer coefficients. In this paper, we apply transformers to predict these coefficients. The problem can be formulated in a language-like representation amenable to standard cross-entropy training objectives. We design two related experiments and show that the model achieves high accuracy (

>

98
%

)

on both tasks. Our work shows that transformers can be applied successfully to problems in theoretical physics that require exact solutions.
An instanton take on some knot detection results
Authors: Baldwin John , Sivek Steven
Published: August 2024

We give new proofs that Khovanov homology detects the figure eight knot and the cinquefoils, and that HOMFLY homology detects

5
2

5_2

and each of the

P
(
−
3
,
3
,
2
n
+
1
)

P(-3,3,2n+1)

pretzel knots. For all but the figure eight these mostly follow the same lines as in previous work. The key difference is that in honor of Tom Mrowka’s 60th birthday, the arguments here use instanton Floer homology rather than knot Floer homology.
Redemption, 1880–1900
Authors: Wiecek William M
Published: August 2024

This chapter looks into the history of Redemption, which is the aftermath of Reconstruction. It explains that at some point between the political demise of Reconstruction and the Great War, the experience of African Americans in the United States sunk to its lowest point, worse in some ways than during slavery times. Moreover, the Fuller Court consistently struck down federal and state efforts to secure Blacks’ rights. The chapter provides an overview of the ratification of Jim Crow following several cases, such as the Plessy v. Ferguson case. It explores the themes of reconciliation, reunion, white supremacy, and emancipation that emerged from the haze of historical memory after the war.
The Nadir and the Blue Hour, 1900–1920
Authors: Wiecek William M
Published: August 2024

This chapter explains that the blue hour for African Americans came in the years between the Nadir and the 1920s. The Thirteenth Amendment’s ban on involuntary servitude signaled an approaching turnaround in the Court’s thinking. In the decade of the Nadir, the Supreme Court closed the federal courts to African Americans struggling against the disfranchisement inaugurated by the Mississippi Plan. The chapter cites that peonage cases were the first sign that the edifice of Jim Crow was not as sturdy as its supporters thought. The peonage cases began invoking the protections of the Reconstruction Amendments and treated African Americans as rights-bearing citizens.
Tipping Points to Transitions: PEA and NEA (Principles 2 and 3)
Authors: Boyatzis Richard E
Published: August 2024

Chapter 3 discusses the Positive Emotional Attractor (PEA) and Negative Emotional Attractor (NEA), which are tipping points to transitions in sustained, desired change consisting of three axes. The PEA invites openness to new ideas and is energizing and restorative. The NEA act as brakes, slowing or stopping awareness, and is draining and deflating.

One axis is stress (SNS) to renewal (PNS). Another is the DMNto TPN. The third is positive to negative emotions. Together, the PEA enables openness to new ideas, emotions, better immune system functioning, neurogenesis, better cognitive functioning, vagal tone and flourishing. The NEA enables analysis, solving problems, making decisions and focusing attention. These two states suppress each other. Unless the PEA is reinforced over time, a deterioration will cause a tipping point into the NEA state. Emotional and social contagion via swarming play a major role in spreading PEA or NEA in social movements and human collectives.

Sustained, desired change in humans and human systems is most often discontinuous and nonlinear, and is better described as a power curve. Power curves are ubiquitous among humans because one’s actions are connected, not independent. In addition, humans will also seek to defend and protect themselves and their tribes. In addition, people want to be included and typically seek social approval. Lastly, humans will attempt to reduce uncertainty. Emotional and social contagion affects actions in dyads, teams, organizations, communities, and countries in a similar way.
Resonant Relationships Are the Context for Change (Principle 7)
Authors: Boyatzis Richard E
Published: August 2024

Chapter 7 focuses on resonant relationships. Relationships are the context for sustained, desired change. They are the agar agar in the petri dish of life. Resonant relationships are different in that they permeate and modify experiences in each of the other phases along the process of sustained, desired change. Resonant relationships have three qualities: shared vision, shared compassion, and shared energy. Through shared mindfulness, one can achieve a degree of centeredness and joy through playfulness. With a shared vision in the relationship, people can act independently within their own situation but still move together. Shared compassion is caring for others in need and for others who wish to grow, learn, and change. The degree of shared energy in a relationship is probably a more direct measure of the emotional contagion and being in tune with each other than any other quality of resonant relationships.
Photodynamic therapy reduces the burden of small ultraviolet-induced epidermal clones in human and mouse skin
Authors: Wei Lei , Fitzgerald Megan E , Yan Li , Murakami Mitsuko , Grant Sydney R , Hu Qiang , Fan Serena , Okai Bernard , Goyal Divya , Singh Prashant K , Shafirstein Gal , Remenyik Eva , Gellen Emese , Foster Barbara A , Huss Wendy J , Paragh Gyorgy
Published: August 2024

Actinic keratoses (AKs) and keratinocyte carcinomas (KCs) arise from prolonged UV exposure, with precursor UV-induced clonal mutations (CMs) appearing in sun-damaged skin. Photodynamic therapy (PDT) is a common field treatment for AKs and early KCs, but its impact on subclinical CMs is unknown. This study examines CMs using targeted ultra-deep sequencing on epidermal samples. By comparing skin before and after PDT in five patients and a mouse model of chronic UV carcinogenesis, a significant reduction in low-frequency mutations post-treatment was revealed. These findings highlight PDT’s potential in modifying subclinical damage and propose low-variant allele frequency CMs as biomarkers for field treatment efficacy.