bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigation of partial and cloud cavitation control on a hydrofoil using bio-inspired riblets
Authors: Lin Yuxing , Kadivar Ebrahim , el Moctar Ould , Schellin Thomas E.
Published: May 2024

We experimentally investigated a passive cavitation control approach to control partial and cloud cavitation on a National Advisory Committee for Aeronautics 0015 hydrofoil. For this approach, we implemented two different kinds of mesoscale bio-inspired riblets, known as scalloped riblets and sawtooth riblets, on the suction side of the hydrofoil near its leading edge. We studied the dynamics of partial and cloud cavitation on the hydrofoil with and without two kinds of riblets using a high-speed camera. In addition, we performed hydro-acoustic measurements to analyze the effects of this passive control on the cavitation induced noise in the wake of the hydrofoils. We considered flows at Reynolds numbers 0.5 × 106 and 0.6 × 106 with the hydrofoils at angles of attack of 8° and 10°. Results revealed that the cloud cavitation shedding on the hydrofoil suction surface was mitigated significantly due to the reduction in the re-entrant jet momentum. Also, the influence of tip vortex cavitation was reduced on the modified hydrofoils. Furthermore, the large-scale cavitation induced noise for the unmodified hydrofoil was located mostly at lower frequency in the range of 30 Hz, which was similar to the cavity shedding frequency. The small-scale vortex-induced noise concentrated at relative higher frequency between 100 and 120 Hz. The noise reduction in this study was achieved by scalloped and sawtooth riblets at low frequency domain and for some cases at higher frequency range by manipulating of the cavitation oscillation mechanism and elimination of a large-scale cavitation structure. This study provided new insight into controlling the destructive effects of cavitation using bio-inspired riblets, which should be relevant for various engineering applications.
A local scour model for single pile on silty seabed considering soil cohesion (SedCohFOAM): Model and validation
Authors: Qin Chenxi , Duan Lunliang , Wang Duoyin , Duan Bingchuan , Liu Wei
Published: May 2024

In this study, the sediment transport two-phase flow model named SedFOAM is expanded to include soil cohesion, creating a new model named SedCohFOAM within OpenFOAM. The local scouring flume experiment involving a pile on silty seabed and sandy seabed is conducted in a curved flume. Due to the influence of cohesion, the scouring depth at different locations on sandy seabed is 15%–18% greater than that on silty seabed. Observations from this experiment informed the analysis of force balance, wherein the agglomerated silt particles are modeled as large singular entities and the cohesive force is treated as a downward influence that keeps the aggregated particles stationary. Meanwhile, the experimental outcomes are utilized to validate the accuracy of the SedCohFOAM model. The numerical findings demonstrated that SedCohFOAM can simulate the flow field distribution around the pile, variations in seabed shear stress, and alterations in seabed surface morphology. Compared with the SedFOAM model, the SedCohFOAM model has a significantly reduced simulation error in simulating scour on silty seabed. When comparing the cross-sectional profiles of the scour holes derived from the flume experiments with those simulated by SedCohFOAM, it was observed that the ultimate-equilibrium scour depth predicted by the model is consistently lower, but the scour radius in the numerical simulations is larger. The deviation from the experimental results is nearly within 8%, while when the flow velocity is high, the simulation error of the simulated scouring depth behind the pile and the scouring radius in front of pile is amplified.
Characterization of pure organic NTI crystals for direct x-ray detection
Authors: Shang Rongjin , Xu Lingyan , Wang Yingming , Liang Lu , Qin Zhentao , Jiang Kai , Jie Wanqi
Published: May 2024

Accurate detection of x-ray radiation is essential for tissue equivalence detection and safety control during medical radiotherapy. Here, a promising radiation detector based on organic 1,8-naphthalimide (C12H7NO2, NTI) single crystals is proposed. NTI single crystals with dimensions of 8 × 2 × 1 mm3 were synthesized by an optimized solvent-cooling method, and the crystal structure was characterized to elucidate the anisotropy mechanism. The coplanar detector made by NTI has a leakage current of less than 0.1 pA at an electric field strength of 1 kV cm−1 and provides excellent detection of 5.49 MeV α-particles (241Am) with a full-energy peak resolution of up to 32.3%. The calculated electron mobility (μe) and electron mobility-lifetime product (μτ)e were 7.9 cm2 V−1s−1 and 1.56 × 10−6 cm2 V−1, respectively. Additionally, the detection limit of the NTI detector was 0.35 µGy s−1 in the electric field strength range of 0.2–1.0 kV cm−1 under a 20 kV x-ray beam with a high sensitivity of 56.2 μC Gy−1cm−2. Consequently, the NTI detector achieves an excellent spatial resolution of 0.8–0.9 lp mm−1 in terms of x-ray imaging capability.
Characterizing unstructured data with the nearest neighbor permutation entropy
Authors: Voltarelli Leonardo G. J. M. , Pessa Arthur A. B. , Zunino Luciano , Zola Rafael S. , Lenzi Ervin K. , Perc Matjaž , Ribeiro Haroldo V.
Published: May 2024

Permutation entropy and its associated frameworks are remarkable examples of physics-inspired techniques adept at processing complex and extensive datasets. Despite substantial progress in developing and applying these tools, their use has been predominantly limited to structured datasets such as time series or images. Here, we introduce the k-nearest neighbor permutation entropy, an innovative extension of the permutation entropy tailored for unstructured data, irrespective of their spatial or temporal configuration and dimensionality. Our approach builds upon nearest neighbor graphs to establish neighborhood relations and uses random walks to extract ordinal patterns and their distribution, thereby defining the k-nearest neighbor permutation entropy. This tool not only adeptly identifies variations in patterns of unstructured data but also does so with a precision that significantly surpasses conventional measures such as spatial autocorrelation. Additionally, it provides a natural approach for incorporating amplitude information and time gaps when analyzing time series or images, thus significantly enhancing its noise resilience and predictive capabilities compared to the usual permutation entropy. Our research substantially expands the applicability of ordinal methods to more general data types, opening promising research avenues for extending the permutation entropy toolkit for unstructured data.
Finite element modeling of ultrasonic attenuation and dispersion in graded multilayer polymer composites
Authors: Zhou Bo , Yin Guanchao , Geng Xiangwei , Zhang Ruizhi , Luo Guoqiang , Shen Qiang , Zhang Jian
Published: May 2024

In this paper, finite element models of ultrasonic wave propagation in Cu–PMMA composites are established. The effects of second-phase particles, ultrasonic properties, and graded interfaces on the ultrasonic propagation behavior are investigated, and the contributions of particle-independent scattering, particle interactions, and matrix viscoelasticity to the ultrasonic attenuation are quantitatively evaluated. The results show that there is no obvious coupling between particle scattering and matrix viscoelasticity in Cu–PMMA composites, and the longitudinal wave speed has little effect with the variation of particle size, ultrasonic frequency, and graded interface, while the variation of the acoustic attenuation coefficient is related to the disorder of ultrasonic energy propagation direction. In the intra-layer uniform model, with the increase in Cu particle size and ultrasonic frequency, the scattering effect of Cu particles on the ultrasonic waves is enhanced, resulting in a significant increase in the acoustic attenuation coefficient. In the inter-layer graded multilayer model, there is a strong reverse energy propagation between the layers, causing the acoustic attenuation coefficient to increase significantly.
Orifice section velocity fitting method and its application in flash spray research
Authors: Zheng Lei , Chen Hua , Fu Hao , Cheng Wen-Long
Published: May 2024

Although spray technology is widely used, research on spray flow is limited by the complexity of its flow field. To simplify the spray simulation, this work proposed an orifice section velocity fitting method, which can simplify the calculation of the flow field inside the nozzle by using a set of special velocity fitting equations as boundary conditions. For the application and verification of the method, the characteristics of methyl nonafluorobutyl ether (HFE7100) flash spray under temperature influence were experimentally studied in this paper using phase Doppler particle analyzer equipment and compared the results of simulation and experiment. The comparison results show that the simulation and experimental results of the spray axial velocity distribution have good consistency at different temperatures. The simulation results show that the swirling flow in the orifice is stronger when the temperature is lower than the boiling point and the spray velocity isosurface is conical. The swirling flow in the nozzle is attenuated by flash evaporation when the temperature increases above the boiling point, while the spray velocity isosurface changes to a bell shape. The experimental results show that the spray velocity increases with increasing evaporation caused by increasing temperature and that the spray axial velocity distribution also changes from a saddle shape to a single peak shape. The spray droplet size increased significantly under the influence of flash evaporation, but the spatial distribution maintained a saddle shape. This study can provide a reference for spray simulation analysis and the study of flash spray characteristics.
Strain-driven high energy storage in BaTiO3-based lead-free epitaxial thin films
Authors: Liang Zhongshuai , Wang Jiawei , Liu Xin , Li Chao , Du Xianfeng
Published: May 2024

In this work, the epitaxial 0.85BaTiO3-0.15Bi(Mg1/2Ti1/2)O3 (BT-BMT) films with large compressive strain were fabricated on SrTiO3 (001). The expansion of the unit cell volume and out-of-plane lattice parameter and the large built-in electric field (Ebi) in BT-BMT films indicate the existence of defect dipoles. It was found that the polarization and the breakdown strength can be optimized by the strain and the defects, respectively. Ultimately, a desirable energy density of 90.3 J/cm3 with efficiency of 62.3% was achieved. It suggests that strain can serve as a practical means to modulate the energy storage performance of ferroelectric epitaxial film capacitors.
871 nm single-frequency fiber laser for Yb+ ion optical clock
Authors: AlYahyaei Khawlah , Zhu Xiushan , Norwood Robert A. , Peyghambarian Nasser
Published: May 2024

In recent years, there has been a dramatically increasing demand for high-performance narrow-linewidth lasers for optical atomic clock and quantum applications. In this paper, we report on a single-frequency distributed Bragg reflector fiber laser operating at 871 nm that can be used to produce a 435.5 nm narrow-linewidth laser for a Yb+ clock via second-harmonic generation. Linearly polarized single-longitudinal-mode laser output with a power of 6.7 mW and a polarization extinction ratio of 29 dB was obtained by using a 3-cm long 1 wt. % neodymium (Nd3+)-doped phosphate fiber as the gain fiber.
Dark-soliton asymptotics for a repulsive nonlinear system in a baroclinic flow
Authors: Wu Xi-Hu , Gao Yi-Tian , Yu Xin
Published: May 2024

In geophysical hydrodynamics, baroclinic instability denotes the process in which the perturbations draw the energy from the mean flow potential power. Researchers focus their attention on the baroclinic instability in the Earth's atmosphere and oceans for the meteorological diagnosis and prediction. Under investigation in this paper is a repulsive nonlinear system modeling the marginally unstable baroclinic wave packets in a baroclinic flow. With respect to the amplitude of the baroclinic wave packet and correction to the mean flow resulting from the self-rectification of the baroclinic wave, we present a Lax pair with the changeable parameters and then derive the N-dark-dark soliton solutions, where N is a positive integer. Asymptotic analysis on the N-dark-dark solitons is processed to obtain the algebraic expressions of the N-dark-dark soliton components. We find that the obtained phase shift of each dark-dark soliton component is relevant with the N − 1 spectral parameters. Furthermore, we take N = 3 as an example and graphically illustrate the 3-dark-dark solitons, which are consistent with our asymptotic-analysis results. Our analysis may provide the explanations of the complex and variable natural mechanisms of the baroclinic instability.
IL-33 controls IL-22-dependent antibacterial defense by modulating the microbiota
Authors: Röwekamp Ivo , Maschirow Laura , Rabes Anne , Fiocca Vernengo Facundo , Hamann Lutz , Heinz Gitta Anne , Mashreghi Mir-Farzin , Caesar Sandra , Milek Miha , Fagundes Fonseca Anna Carolina , Wienhold Sandra-Maria , Nouailles Geraldine , Yao Ling , Mousavi Soraya , Bruder Dunja , Boehme Julia D. , Puzianowska-Kuznicka Monika , Beule Dieter , Witzenrath Martin ,   CAPNETZ Study Group, Löhning Max , Klose Christoph S. N. , Heimesaat Markus M. , Diefenbach Andreas , Opitz Bastian , Fuchs André , Engelmann Maximilian , Paul Gregor , Ayoub Mousa , Groehl Katharina , Riedl Katrin , Stolz Daiana , Bauer Wolfgang , Diehl-Wiesenecker Eva Corinna , von Wunsch-Rolshoven Terue Iris , Galtung Noah , Suttorp Norbert , Witzenrath Martin , Wildberg Christian , Pley Caitlin , Zessin Enrico , Schmager Sibylle , Schaaf Bernhard , Kremling Julius , Nickoleit-Bitzenberger Daniela , Azzaui Harun , Hower Martin , Hempel Frederik , Prebeg Katharina , Popkirova Kalina , Kolditz Martin , Schulte-Hubbert Bernhard , Langner Simona , Rohde Gernot , Bellinghausen Carla , Grϋnewaldt Achim , Endres Adrian , Frigerio Carlo , Fiedler Benno , Panning Marcus , Welte Tobias , Pink Isabell , Drick Nora , Fϋhner Thomas , van’t Klooster Mariet , Steinberg Tabea , Barten-Neiner Grit , Kröner Waldemar , Unruh Olesya , Adaskina Nina , Eberhardt Frank , Julius Christina , Illig Thomas , Klopp Norman , Pletz Mathias , Schleenvoigt Benjamin T. , Bahrs Christina , Moeser Anne , Ankert Juliane , Sommerwerck Urte , Wintermantel Tobias , Drömann Daniel , Parschke Patrick , Franzen Klaas , Rupp Jan , Waldeck Frederike , Käding Nadja , Spinner Christoph , Erber Johanna , Voit Florian , Schneider Jochen , Falcone Marco , Tiseo Giusy , Heigener David , Hering Iris , Albrich Werner , Rassouli Frank , Wirth Benjamin , Neurohr Claus , Essig Andreas , Stenger Steffen , Wallner Michael , Burgmann Heinz , Traby Ludwig , Schubert Lorenz ,   and all study nurses
Published: May 2024

IL-22 plays a critical role in defending against mucosal infections, but how IL-22 production is regulated is incompletely understood. Here, we show that mice lacking IL-33 or its receptor ST2 (IL-1RL1) were more resistant to
Streptococcus pneumoniae
lung infection than wild-type animals and that single-nucleotide polymorphisms in
IL33
and
IL1RL1
were associated with pneumococcal pneumonia in humans. The effect of IL-33 on
S. pneumoniae
infection was mediated by negative regulation of IL-22 production in innate lymphoid cells (ILCs) but independent of ILC2s as well as IL-4 and IL-13 signaling. Moreover, IL-33’s influence on IL-22-dependent antibacterial defense was dependent on housing conditions of the mice and mediated by IL-33’s modulatory effect on the gut microbiota. Collectively, we provide insight into the bidirectional crosstalk between the innate immune system and the microbiota. We conclude that both genetic and environmental factors influence the gut microbiota, thereby impacting the efficacy of antibacterial immune defense and susceptibility to pneumonia.
ZmPILS6 is an auxin efflux carrier required for maize root morphogenesis
Authors: Cowling Craig L. , Homayouni Arielle L. , Callwood Jodi B. , McReynolds Maxwell R. , Khor Jasper , Ke Haiyan , Draves Melissa A. , Dehesh Katayoon , Walley Justin W. , Strader Lucia C. , Kelley Dior R.
Published: May 2024

Plant root systems play a pivotal role in plant physiology and exhibit diverse phenotypic traits. Understanding the genetic mechanisms governing root growth and development in model plants like maize is crucial for enhancing crop resilience to drought and nutrient limitations. This study focused on identifying and characterizing ZmPILS6, an annotated auxin efflux carrier, as a key regulator of various crown root traits in maize. ZmPILS6-modified roots displayed reduced network area and suppressed lateral root formation, which are desirable traits for the “steep, cheap, and deep” ideotype. The research revealed that ZmPILS6 localizes to the endoplasmic reticulum and plays a vital role in controlling the spatial distribution of indole-3-acetic acid (IAA or “auxin”) in primary roots. The study also demonstrated that ZmPILS6 can actively efflux IAA when expressed in yeast. Furthermore, the loss of ZmPILS6 resulted in significant proteome remodeling in maize roots, particularly affecting hormone signaling pathways. To identify potential interacting partners of ZmPILS6, a weighted gene coexpression analysis was performed. Altogether, this research contributes to the growing knowledge of essential genetic determinants governing maize root morphogenesis, which is crucial for guiding agricultural improvement strategies.
Tau fibrils induce nanoscale membrane damage and nucleate cytosolic tau at lysosomes
Authors: Rose Kevin , Jepson Tyler , Shukla Sankalp , Maya-Romero Alex , Kampmann Martin , Xu Ke , Hurley James H.
Published: May 2024

The prion-like spread of protein aggregates is a leading hypothesis for the propagation of neurofibrillary lesions in the brain, including the spread of tau inclusions associated with Alzheimer’s disease. The mechanisms of cellular uptake of tau seeds and subsequent nucleated polymerization of cytosolic tau are major questions in the field, and the potential for coupling between the entry and nucleation mechanisms has been little explored. We found that in primary astrocytes and neurons, endocytosis of tau seeds leads to their accumulation in lysosomes. This in turn leads to lysosomal swelling, deacidification, and recruitment of ESCRT proteins, but not Galectin-3, to the lysosomal membrane. These observations are consistent with nanoscale damage of the lysosomal membrane. Live cell imaging and STORM superresolution microscopy further show that the nucleation of cytosolic tau occurs primarily at the lysosome membrane under these conditions. These data suggest that tau seeds escape from lysosomes via nanoscale damage rather than wholesale rupture and that nucleation of cytosolic tau commences as soon as tau fibril ends emerge from the lysosomal membrane.
Molecular basis for antibody recognition of multiple drug–peptide/MHC complexes
Authors: Maso Lorenzo , Rajak Epsa , Bang Injin , Koide Akiko , Hattori Takamitsu , Neel Benjamin G. , Koide Shohei
Published: May 2024

The HapImmuneTMplatform exploits covalent inhibitors as haptens for creating major histocompatibility complex (MHC)-presented tumor-specific neoantigens by design, combining targeted therapies with immunotherapy for the treatment of drug-resistant cancers. A HapImmune antibody, R023, recognizes multiple sotorasib-conjugated KRAS(G12C) peptides presented by different human leukocyte antigens (HLAs). This high specificity to sotorasib, coupled with broad HLA-binding capability, enables such antibodies, when reformatted as T cell engagers, to potently and selectively kill sotorasib-resistant KRAS(G12C) cancer cells expressing different HLAs upon sotorasib treatment. The loosening of HLA restriction could increase the patient population that can benefit from this therapeutic approach. To understand the molecular basis for its unconventional binding capability, we used single-particle cryogenic electron microscopy to determine the structures of R023 bound to multiple sotorasib–peptide conjugates presented by different HLAs. R023 forms a pocket for sotorasib between the VHand VLdomains, binds HLAs in an unconventional, angled way, with VLmaking most contacts with them, and makes few contacts with the peptide moieties. This binding mode enables the antibody to accommodate different hapten–peptide conjugates and to adjust its conformation to different HLAs presenting hapten–peptides. Deep mutational scanning validated the structures and revealed distinct levels of mutation tolerance by sotorasib- and HLA-binding residues. Together, our structural information and sequence landscape analysis reveal key features for achieving MHC-restricted recognition of multiple hapten–peptide antigens, which will inform the development of next-generation therapeutic antibodies.
Shadowing textbook and authentic materials in beginning L2 learners’ acquisition of Mandarin Chinese tones in spontaneous speech
Authors: Lu Ai-Ling , Su Danjie
Published: May 2024

Addressing the lack of research examining the use of discourse-level speech input in beginning L2 learners’ Mandarin tone production in spontaneous speech, this study compares the effects of authentic videos and textbook audios as shadowing materials on beginners’ multisyllabic tone production in spontaneous speech and learner attitudes. Fourteen college students, randomly divided into the “authentic” and “textbook” groups, shadowed for four weeks. From the pretest to the posttest, both groups significantly improved tone accuracy in sentence-level spontaneous speech with no significant differences between groups. Quantitative and qualitative analyses of learners’ responses show that (1) both groups had positive attitudes toward the materials, (2) authentic materials generated greater interest, and learners appreciated shadowing authentic conversations or conversations that mimic natural discourse, and (3) the learners primarily cared about whether the materials were comprehensible, interesting, and accessible. The findings shed light on using authentic materials to teach L2 pronunciation.
What can be said?
Authors: Crane Thera Marie , Lubambo Remah , Mabena M Petrus , Nkwinika Cordelia , Sibisi Muhle , Slater Onelisa
Published: May 2024

We employ a cluster approach to explore the comparative semantic maps of several markers of modal possibility –
the “potential” prefix nga‑ and expressions meaning, roughly, ‘know how to’ and ‘be able to’ – in four South
African Nguni languages: isiNdebele, isiZulu, isiXhosa, Siswati. We also compare the Nguni results with results from Xitsonga, a
closely related language outside of the Nguni clade. The languages exhibit cross-linguistic differences in the expansion of core
meanings, some of which do not appear to follow the cross-linguistically common diachronic pattern in which goal-oriented modality
precedes deontic modality. In addition, the distinction between inherent and learned ability is salient in several of these
languages. Semantic maps of the markers’ functional distributions further show the diversity of modal systems that can be found
even in closely related languages in significant contact with one another.
Anxiety in task-based language teaching
Authors: An Hyejin , Li Shaofeng
Published: May 2024

This chapter provides a comprehensive review of the methods and findings of the research examining
anxiety in learners’ task performance and language development. Based on a thorough search of multiple databases and a
set of selection criteria, 35 studies were included in the review. The investigation of the methodological designs
shows that most studies examined adult, L2 English, and intermediate learners; adopted a within-subjects design; used
dialogic tasks; and measured L2 anxiety by means of the FLCAS. The studies examined the role of anxiety in TBLT from
four perspectives: (1) the role of anxiety in task-based corrective feedback, (2) the influence of L2 anxiety on task
performance in simple and complex tasks, (3) the associations between anxiety and task engagement, and (4) the impact
of task modality on the level of L2 anxiety. Corresponding to the four perspectives, the following findings are
obtained. First, high-anxiety learners tend to benefit more from implicit than explicit feedback and prefer to receive
implicit feedback, and the amount of anxiety caused by feedback can be mitigated by positive delivery of feedback.
Second, the role of anxiety is more evident in complex tasks than simple tasks, and less anxious learners benefit more
from complex tasks while more anxious learners benefit more from simple tasks. Third, more anxious learners show less
task engagement. Fourth, computer-mediated communication causes less anxiety than face-to-face communication, with the
caveat that anxiety about new technology may increase anxiety.
Task-based language learning and teaching
Authors: Oliver Rhonda , Bogachenko Tatiana
Published: May 2024

Different theoretical perspectives have informed task-based research exploring variables related to
individual differences. Whilst the majority of studies have been undertaken with adult learners, there is a small and
growing body of work investigating what younger learners do when they use tasks. Informed by the literature and
database search, this review extends our previous paper (Oliver & Bogachenko,
2019), addressing the specific individual difference of age. It outlines differences in
the way younger and older learners approach tasks, how they negotiate for meaning, whether or not and how they use
input and different types of feedback (e.g., recasts), and how and to what extent they modify their output. The
findings show that other factors, such as type of tasks and task modality, learner proficiency, context of learning
(e.g., teacher-fronted, types of peer pairings) combine with age to impact the type of task-based interactions that
occur. It also suggests teachers may be more or less effective using task-based teaching according to the age of their
learners, for example, either by scaffolding pre-task (for younger learners) or providing support during task (for
older learners). Pedagogically, however, the research shows that regardless of age, learners benefit from task-based
interaction and in a range of instructional settings. Even so, there are clear age differences, and it is vital that
the age of learners is taken into account. Much more research is needed to further develop age-appropriate task
guidelines for teachers.
Conclusion
Authors: Ellis Rod
Published: May 2024

This chapter begins by raising a number of general issues concerning the investigation of
individual differences in task-based language teaching (TBLT) – the importance of investigating IDs in task-based
language lessons as well as in individual tasks, including the study of input-based as well as output-based tasks, the
selection of IDs to be investigated, and the need to make a clear distinction between IDs and engagement/emotion. The
chapter then outlines a framework that can guide the study of IDs in TBLT where IDs along with teacher factors and
situational context mediate task outcomes via how participants engage with a task. Finally, the chapter comments on
pedagogical issues by considering what IDs should teachers consider in designing, implementing, or adapting tasks, how
they can find out how their learners differ, and how they can accommodate learner IDs in TBLT.
Mitochondria–ER–PM contacts regulate mitochondrial division and PI(4)P distribution
Authors: Casler Jason C. , Harper Clare S. , White Antoineen J. , Anderson Heidi L. , Lackner Laura L.
Published: May 2024

The mitochondria–ER–cortex anchor (MECA) forms a tripartite membrane contact site between mitochondria, the endoplasmic reticulum (ER), and the plasma membrane (PM). The core component of MECA, Num1, interacts with the PM and mitochondria via two distinct lipid-binding domains; however, the molecular mechanism by which Num1 interacts with the ER is unclear. Here, we demonstrate that Num1 contains a FFAT motif in its C-terminus that interacts with the integral ER membrane protein Scs2. While dispensable for Num1’s functions in mitochondrial tethering and dynein anchoring, the FFAT motif is required for Num1’s role in promoting mitochondrial division. Unexpectedly, we also reveal a novel function of MECA in regulating the distribution of phosphatidylinositol-4-phosphate (PI(4)P). Breaking Num1 association with any of the three membranes it tethers results in an accumulation of PI(4)P on the PM, likely via disrupting Sac1-mediated PI(4)P turnover. This work establishes MECA as an important regulatory hub that spatially organizes mitochondria, ER, and PM to coordinate crucial cellular functions.
Necessity of quantizable geometry for quantum gravity
Authors: Mehta A K
Published: May 2024

In this paper, Dirac Quantization of 3D gravity in the first-order formalism is attempted where instead of quantizing the connection and triad fields, the connection and the triad 1-forms themselves are quantized. The exterior derivative operator on the space of differential forms is treated as the ‘time’ derivative to compute the momenta conjugate to these 1-forms. This manner of quantization allows one to compute the transition amplitude in 3D gravity which has a close, but not exact, match with the transition amplitude computed via LQG techniques. This inconsistency is interpreted as being due to the non-quantizable nature of differential geometry.
Calculation of electron scattering lengths on Ar, Kr, Xe, Rn and Og atoms
Authors: Syty Paweł , Piłat Michał P , Sienkiewicz Józef E
Published: May 2024

Focusing on the noble gases, we calculate the scattering potential using the Dirac–Coulomb Hamiltonian supplemented with a model polarization potential. We determine the scattering lengths using two methods, namely phase shifts for very small scattering energies and the shape of the wave function for zero scattering energy. We compare our theoretical electron scattering length results on Ar, Kr and Xe atoms with existing experimental and theoretical data. In turn, the results obtained for the first time for Rn and Og atoms require independent confirmation. The analysis conducted indicates that the source of the greatest uncertainty in the obtained results is the literature values of dipole polarizability. The study used the GRASP2018 computational package for bound states and the modified COWF code for continuum states.
Cooper minima in high-Z atoms: effects of correlation and relativity on np photoionization
Authors: Baral S , Jose J , Deshmukh P C , Manson S T
Published: May 2024

Photoionization dipole transition matrix elements pass through a zero or attain a minimum that leaves imprints on photoionization parameters like the cross-section, angular distribution asymmetry parameter, phase shift, and photoionization time delay. This minimum is commonly known as the ‘Cooper minimum’ (CM). The CM, in general, is strongly affected by relativistic and correlation effects. Previous works investigated CM in the 6p and 5p subshell photoionization up to Z = 100 using the single-particle Dirac-Slater (DS) method. The present work extends the earlier work to Z up to 120 using more accurate methods; Dirac–Hartree–Fock (DHF) which includes the relativistic effects and exchange correlations, and the relativistic random phase approximation (RRPA) which includes both initial and final state electron-electron correlations along with relativistic effects. In addition to the study of photoionization from the 6p and 5p subshells, the 4p subshell has also been investigated in the present work. To demonstrate the prominent effects in the high-Z atoms, Rn (Z = 86), Ra (Z = 88), No (Z = 102), Cn (Z = 112), Og (Z = 118), and Ubn (Z = 120) are investigated.
Strain and piezoelectric control of electronic and photonic properties of p − n diodes
Authors: Barettin Daniele , Willatzen Morten
Published: May 2024

Piezoelectricity is a well-known effect in a vast number of technologically important insulators and semiconductors and exists in 20 out of the 32 three-dimensional crystal classes. The piezoelectric effect is the driving mechanism behind several classical sensors and transmitters, and also most recently, in many nanodevices. Zhong Lin Wang coined the fields piezotronics and piezo-phototronics where the piezoelectric effect plays a dominant role. Piezoelectricity couples in a linear fashion mechanical strain to electrical fields and vice versa. In solids, there is another linear coupling between strain and the electric potential, known as the deformation potential effect. While linear in its coupling nature, this effect does not require the solid to be non-centrosymmetric in contrast to the piezoelectric effect. Moreover, the deformation potential effect is quantitatively huge and leads to changes in the conduction and valence band edges of III–V and II–VI materials of, typically, 50–100 meV in the presence of 1 % strain. Therefore, the deformation potential effect is essential to determine the electronic and photonic properties of bulk and nanostructure semiconductors in the presence of strain. In this work, we compute the relative importance of piezoelectricity and the deformation potential effect in the presence of lattice mismatch and external strain. We choose p − n junctions of ZnO/GaN structures but anticipate that the general conclusions can be carried over to other material structures. The main result of the present work is that both the inclusion of the deformation potential effect and piezoelectricity is crucial to correctly compute the effect of strain on p − n junction current–voltage curves and photonic properties. In our analysis of wurtzite heterostructures, the spontaneous polarization effect is also included but this effect appears to play a minor role for electronic and photonic properties.
Electron scattering cross sections of 1,1,1,2-tetrafluoroethane (R134a)
Authors: Metting van Rijn Marnik , Biagi Stephen F , Franck Christian M
Published: May 2024

A revised set of electron-molecule-scattering cross section for the refrigerant R134a (

CF
3

CH
2

F

) is presented. Swarm studies acquired on a Pulsed Townsend apparatus experimentally verified the electron-transport-coefficient simulations. Increasing the cross sections’ quality enhances the accuracy in modelling particle detectors operating with R134a, as the cross sections serve as input for the simulations.
Electric dipole polarizability of low-lying excited states in atomic nuclei
Authors: Orce José Nicolás , Ngwetsheni Cebo
Published: May 2024

New equations for the electric dipole polarizability α
E1 of low-lying excited states in atomic nuclei—and the related (−2) moment of the total photo-absorption cross section, σ
−2—are inferred in terms of electric dipole and quadrupole matrix elements. These equations are valid for arbitrary angular momenta of the initial/ground and final/excited states and have been exploited in fully converged 1ℏ
ω shell-model (SM) calculations of selected p- and sd-shell nuclei that consider configuration mixing; advancing previous knowledge from 17O to 36Ar, where thousands of electric dipole matrix elements are computed from isovector excitations which include the giant dipole resonance (GDR) region. Our results are in reasonable agreement with previous SM calculations and follow—except for 6,7Li and 17,18O—Migdal’s global trend provided by the combination of the hydrodynamic model and second-order non-degenerate perturbation theory. Discrepancies in 6,7Li and 17O arise as a result of the presence of α-cluster configurations in odd-mass nuclei, whereas the disagreement in 18O comes from the mixing of intruder states, which is lacking in the SM interactions. More advanced ab initio calculations of the dipole polarizability for low-lying excited states covering all the isovector states within the GDR region are missing and could be very valuable to benchmark the results presented here and shed further light on how atomic nuclei polarize away from the ground state
Probing electroweak phase transition in extended singlet scalar model with resonant HH production in bbZZ channel using parameterized machine learning
Authors: Palit Pritam , Shil Sujay
Published: May 2024

In this paper, a collider signature of a heavy Higgs boson at 14 TeV HL-LHC is studied, where the heavy Higgs boson decays into a pair of standard model (SM) Higgs boson, which further decays to bbZZ state and subsequently to bb
ℓ
+
ℓ
−
ν

ℓ

ν

ℓ
final state. To study this, we consider singlet scalar extension of the SM and select the parameter space and mass of the heavy Higgs boson such that it prefers a strong first-order electroweak phase transition (EWPT). The study is done following the bbZZ analysis of CMS Collaboration and further using parameterized machine learning for final discrimination which simplifies the training process along with an improved discrimination between signal and background over the range of benchmark points. Despite the lower branching fraction, this channel can be a potential probe of the EWPT with the data sets collected by the CMS and ATLAS experiments at the 14 TeV HL-LHC with 3 ab−1 of integrated luminosity and a production of resonant di-Higgs signal can be potentially discovered up to 490 GeV of resonance mass.
Research on bearing remaining useful life anti-noise prediction based on fusion of color-grayscale time-frequency features
Authors: Jia Wenchao , An Aimin , Du Xianjun , Shi Yaoke , Gong Bin
Published: May 2024

In contemporary industrial processes, vibration signals collected from bearings often contain significant noise, challenging the efficacy of conventional predictive models in extracting critical degradation features and accurately predicting the remaining useful life (RUL) of bearings. Addressing these challenges, this paper introduces a novel method for predicting bearing RUL under noisy conditions, leveraging a dual-branch multi-scale convolutional attention network (DMCSA) integrated with a dense residual feature fusion network (DRF). Initially, the method applies continuous wavelet transform (CWT) to vibration signals to extract color time-frequency image data, followed by grayscale processing to construct a comprehensive color-grayscale time-frequency image dataset, thereby augmenting the model’s input features. Enhanced channel and spatial attention mechanisms, combined with multi-scale convolutions, facilitate superior feature extraction and selection. The model’s resilience to noise is fortified by incorporating noise into the training dataset. Subsequently, selected color-gray time-frequency features undergo fusion and relearning through the DRF framework at the model’s backend. The crayfish optimization algorithm (COA) is deployed for the astute determination of the model’s critical hyperparameters. The proposed DMCSA-DRF model is then applied to predict the health indicator (MSCA-DRF-HI) of the test dataset, culminating in the accurate prediction of the bearings’ RUL. Validation experiments demonstrate that our method surpasses comparative models in prediction accuracy under diverse noise interferences, signifying a substantial advancement in predictive performance.
Iterative feature mode decomposition: a novel adaptive denoising method for mechanical fault diagnosis
Authors: Ruan Xiaolong , Yuan Rui , Dang Zhang , Lv Yong , Jing Xiaolong
Published: May 2024

Remaining useful life prediction of rolling bearings highly relies on feature extraction of signals. The use of denoising algorithms helps to better eliminate noise and extract features, thereby constructing health indicators to predict remaining useful life. This paper proposes a novel adaptive denoising method based on iterative feature mode decomposition (IFMD) to accurately and efficiently extract fault features. The feature mode decomposition (FMD) employs correlation kurtosis (CK) as the objective function for iterative filter bank updates, enabling rapid identification of fault features. To achieve IFMD, the sparrow search algorithm combines sine-cosine algorithm and cauchy variation (SCSSA) to optimize two key parameters in FMD. During the continuous iteration process of the SCSSA algorithm, filter length and number of modes were determined. IFMD does not require empirical setting of initial parameters. During iterative process, the signal is accurately decomposed and the noise is eliminated. Compared with other optimization algorithms, SCSSA has obvious advantages in iterative rate and global optimization. The envelope spectrum feature energy ratio (ES-FER) is used to select decomposed modes, and the mode with the largest ES-FER is chosen as the optimal mode. Bearing fault diagnosis is realized by envelope spectrum analysis of the optimal mode. The numerical simulations and experimental verifications both validate the effectiveness and superiority of the proposed IFMD in mechanical fault diagnosis.
Versatile simplistic correction of T-higrow sensors for improved soil moisture measurement accuracy
Authors: Abdelal Qasem , Al-Kilani Muhammad Rasool
Published: May 2024

The use of soil moisture sensors for irrigation can help reduce water and energy consumption and risks of groundwater contamination, which are essential aspects for pursuing sustainable development goals. However, increased adoption of this technology is limited by calibration requirements, technical complexities, and sensor costs. In this work, a simplified method for reducing the measurement error of a recently released low-cost soil sensor (T-Higrow) is presented. The method only requires measurements of a dry sample from the target soil, which are inputted into a simple correction formula to reduce the measurement error at higher moisture levels. The requirements of the proposed method are simple enough for most labs or extension services. This method was compared to the commonly used linear, polynomial, and logarithmic regression models based on repeated bench-scale experiments within 0%–35% moisture range in silt and sandy loam soils and in silica sand. Uncorrected sensor readings correlated well with soil moisture (r: 0.94–0.98), but with significant overestimation (25%–60% error). The simplified correction method showed comparable error reduction to regression models across all soil types. All methods reduced error down to 2%–10% (0.02–0.1 cm3 cm−3) and maintained high correlations (r > 0.94), except for logarithmic regression which reduced correlation by around 3%. Variability amongst sensor measurements was generally low (Standard Deviation: 0.01–0.03) particularly at moisture ranges below 20%, this was also the case for sensor-to-sensor variability (Standard Deviation: 0.01–0.03). Sensor evaluation and calibration works are needed to increase the accessibility to this technology for improved water and energy conservation.
Analysis of fracture damage mechanical properties of particle reinforced polymer composite film based on micro-macro finite element method
Authors: Kong Fangyun , Xu Zhen , Yang Yuqi , Wang Zhenqing
Published: May 2024

The particle reinforcement and related effect on fracture damage mechanical properties of polymers have been studied in this paper. Based on the uniaxial tensile test result of SiO2 particle reinforced polyvinylidene fluoride (PVDF) composites, the parameters of macro elastic-plastic finite element model and micro particle reinforced model are obtained. The effects of boundary conditions, shape and size of damage notch on fracture damage mechanical properties of PVDF composites are studied from macroscopic view. The uniaxial tensile mechanical properties and elastic modulus are increased with notch angle (0°, 30°, 60°, 120°). The damage analysis of the micro model shows that the mechanical properties of SiO2/PVDF composites are best when the content of SiO2 is 6%. Debonding between particles and matrix indicates have great effect on crack propagation. The micro-macro finite element model is effective tool to study the damage mechanical properties of particle reinforced polymers.
Tailoring the extension-bending-twisting coupling in composite laminates using carbon nanotube hybridization
Authors: Bedi Harpreet Singh , Padhee Srikant S , Agnihotri Prabhat K
Published: May 2024

The existence of extension-bend-twist coupling of deformations in composites is a complex problem. Ability to tailor the coupling response as per the requirement is desirable to harness the high strength-to-weight ratio of composites in many structural applications. Here we report a feasible design strategy to tune the extent of deformation coupling in composite laminates. To this end, carbon nanotube (CNT) grafted lamina is incorporated in the lay-up of conventional composites. Classical laminate theory (CLT) and finite element analysis show that the coupling extent of extension-twist, extension-bending and extension- bending-twist can be suitably designed by varying the number, location and distribution of CNT grafted lamina in a laminate configuration. Theoretical and computational results reveal maximum extension-twist coupling when a single CNT grafted lamina is placed closer to the mid-plane in a 16 ply antisymmetric laminate. Symmetrical placement of CNT grafted lamina avoids the extension-bend coupling. Finite element analysis shows that the lateral bending of composite cantilever beam under combined axial and bending loads can be designed by suitably choosing the configuration of the modified laminate. These findings will significantly contribute in designing structural composites for advanced applications.
Impurity characterization in diamond for quantum and electronic applications: advances with time-resolved cathodoluminescence
Authors: Arnold C , Temgoua S , Barjon J
Published: May 2024

The ultimate purity of synthetic diamond crystals is currently limited by traces of boron and nitrogen. Here we study diamond crystals grown at high-pressure high-temperature, which are made of 3D growth sectors with variable residual impurity contents. The boron concentration is found in the 0.5–6.4 ppb range thanks to continuous cathodoluminescence analysis. Time-resolved cathodoluminescence experiments complete the impurity analysis with measurements of free exciton lifetimes. From them, we deduced an estimate of the nitrogen concentration at the ppb level, from 0.6 to 30 ppb depending on the growth sectors. We identified n-type, p-type and highly compensated regions, which illustrates the potential of cathodoluminescence as a local characterization tool for qualifying diamond for electronic and quantum applications.
Asymptotic behaviour for solutions to reaction–diffusion equations on a root-like metric graph
*
Authors: Lou Bendong , Morita Yoshihisa
Published: May 2024

In this paper we consider symmetric solutions of reaction–diffusion equations on an unbounded root-like metric graph. We first prove a version of the zero number diminishing properties on the graph, and then use them to show a convergence result for bounded and symmetric solution of general equations. As application, we provide a complete spreading-transition-vanishing trichotomy result on the asymptotic behaviour for solutions of the bistable reaction–diffusion equation on the graph.
Stability and exponential decay for the compressible viscous non-resistive MHD system
Authors: Dong Boqing , Wu Jiahong , Zhai Xiaoping
Published: May 2024

How to construct global solutions of the compressible viscous magnetohydrodynamic (MHD) equations without magnetic diffusion even with small initial data in

R

3

or

T

3

is still an extremely challenging open problem. The difficulty comes from the lack of magnetic diffusion and the fact that solutions to inviscid equations generally grow in time. Motivated by this open problem, the present paper focuses on a special case of this MHD system in

T

3

when the magnetic field is vertical. We establish the global existence and uniqueness of smooth solutions to this system near a steady-state solution. In addition, the solution is shown to be stable and decay exponentially in time. The proof discovers and makes use of the smoothing and stabilizing effect of the steady magnetic field on the perturbations.