bluuebunny/crossref_metadata_2025 huggingface dataset:
Negative Surface Chlorophyll Concentration Anomalies in the Southeast Arabian Sea During Summer in 2015 and 2019
Authors: Huang Huaming , Huang Ke , Yang Lei , Liang Zhanlin , Song Wei , Wang Dongxiao
Published: October 2024

Satellite observations revealed two extremely low surface chlorophyll concentration (SCC) events with a warm sea surface temperature anomaly in the southeastern Arabian Sea (SEAS, 6°–15°N, 72°–77°E) during the summer (July–August–September) in 2015 and 2019. We find that the physical processes leading to these two similar low SCC events are remarkably different. The low SCC in the SEAS during summer 2019 is mainly related to the weakened upwelling and deepening of the thermocline depth due to the combined effects of the local wind anomalies and the arrival of westward‐propagating downwelling coastal Kelvin wave driven by easterly anomalies near the eastern Sri Lanka during an extreme positive Indian Ocean Dipole (IOD) event. In summer 2015, a weaker positive IOD‐induced easterly anomalies in the southern Bay of Bengal also drives downwelling coastal Kelvin waves westward, deepening the thermocline in the SEAS. But unlike that in summer 2019, the local wind stress curl anomalies in the SEAS during summer 2015 favors upwelling, which counteracts the downward motion of the coastal Kelvin waves, leading to weaker downward transport (one‐third of that in 2019). Meanwhile, the upper ocean layer in the SEAS experiences extreme warming during summer owing to the development of 2015/2016 super El Niño. This substantial warming enhances upper oceanic stratification, which results in weaker vertical mixing and reduces the SCC to an extremely low level despite the much weaker IOD strength in 2015.
Kilometer‐Scale Assessment of the Adriatic Dense Water Multi‐Decadal Dynamics
Authors: Pranić Petra , Denamiel Cléa , Vilibić Ivica
Published: October 2024

The North Adriatic Dense Water (NAddW)—the densest Mediterranean water generated by extreme cooling during wintertime hurricane‐strength winds—drives the thermohaline circulation, ventilates the deep layers, and changes the biogeochemical properties of the Adriatic Sea. However, modeling the dynamical properties of such dense water at the climate scale has been a challenge for decades due to the complex coastal geomorphology of the Adriatic basin not properly reproduced by existing climate models. To overcome these deficiencies, a 31‐year‐long simulation (1987–2017) of the Adriatic Sea and Coast (AdriSC) kilometer‐scale atmosphere‐ocean model is used to analyze the main NAddW dynamical phases (i.e., generation, spreading and accumulation). The study highlights four key results. First, during winter, the NAddW densities are higher in the shallow northern Adriatic shelf than in the deeper Kvarner Bay—where 25%–35% of the overall NAddW are found to be generated—due to a median bottom temperature difference of 2°C between the two generation sites. Second, the NAddW mass transported across most of the Adriatic peaks between February and May, except along the western side of the Otranto Strait. Third, for the accumulation sites, the bottom layer of the Kvarner Bay is found to be renewed annually while the renewal occurs every 1–3 years in the Jabuka Pit and every 5–10 years in the deep Southern Adriatic Pit. Fourth, the NAddW cascading and accumulation is more pronounced during basin‐wide high‐salinity conditions driven by circulation changes in the northern Ionian Sea.
TMCO1 is upregulated in breast cancer and regulates the response to pro-apoptotic agents in breast cancer cells
Authors: Bong Alice H. L. , Robitaille Mélanie , Lin Sichun , McCart-Reed Amy , Milevskiy Michael , Angers Stéphane , Roberts-Thomson Sarah J. , Monteith Gregory R.
Published: October 2024

The release of Ca2+ ions from endoplasmic reticulum calcium stores is a key event in a variety of cellular processes, including gene transcription, migration and proliferation. This release of Ca2+ often occurs through inositol 1,4,5-triphosphate receptors and the activity of these channels and the levels of stored Ca2+ in the endoplasmic reticulum are important regulators of cell death in cancer cells. A recently identified Ca2+ channel of the endoplasmic reticulum is transmembrane and coiled-coil domains 1 (TMCO1). In this study, we link the overexpression of TMCO1 with prognosis in node-positive basal breast cancer patients. We also identify interacting proteins of TMCO1, which include endoplasmic reticulum-resident proteins involved in Ca2+ regulation and proteins directly involved in nucleocytoplasmic transport. Interacting proteins included nuclear transport proteins and TMCO1 was shown to have both nuclear and endoplasmic reticulum localisation in MDA-MB-231 basal breast cancer cells. These studies also define a role for TMCO1 in the regulation of breast cancer cells in their sensitivity to BCL-2/MCL-1 inhibitors, analogous to the role of inositol 1,4,5-triphosphate receptors in the regulation of cell death pathways activated by these agents.
An architectural role of specific RNA–RNA interactions in oskar granules
Authors: Bose Mainak , Rankovic Branislava , Mahamid Julia , Ephrussi Anne
Published: October 2024

Ribonucleoprotein (RNP) granules are membraneless condensates that organize the intracellular space by compartmentalization of specific RNAs and proteins. Studies have shown that RNA tunes the phase behaviour of RNA-binding proteins, but the role of intermolecular RNA–RNA interactions in RNP granules in vivo remains less explored. Here we determine the role of a sequence-specific RNA–RNA kissing-loop interaction in assembly of mesoscale oskar RNP granules in the female Drosophila germline. We show that a two-nucleotide mutation that disrupts kissing-loop-mediated oskar messenger RNA dimerization impairs condensate formation in vitro and oskar granule assembly in the developing oocyte, leading to defective posterior localization of the RNA and abrogation of oskar-associated processing bodies upon nutritional stress. This specific trans RNA–RNA interaction acts synergistically with the scaffold RNA-binding protein, Bruno, in driving condensate assembly. Our study highlights the architectural contribution of an mRNA and its specific secondary structure and tertiary interactions to the formation of an RNP granule that is essential for embryonic development.
Electronic structure, global reactivity descriptors and nonlinear optical properties of glycine interacted with ZnO, MgO and CaO for bacterial detection
Authors: Sabry Noha M. , Badry Rania , Abdel-Gawad Fagr Kh. , Elhaes Hanan , Ibrahim Medhat A.
Published: October 2024

Modern laboratory medicine relies on analytical instruments for bacterial detection, focusing on biosensors and optical sensors for early disease diagnosis and treatment. Thus, Density Functional Theory (DFT) was utilized to study the reactivity of glycine interacted with metal oxides (ZnO, MgO, and CaO) for bacterial detection. Total dipole moment (TDM), frontier molecular orbitals (FMOs), FTIR spectroscopic data, electronic transition states, chemical reactivity descriptors, nonlinear optical (NLO) characteristics, and molecular electrostatic potential (MESP) were all investigated at the B3LYP/6–31G(d, p) level using DFT and Time-Dependent DFT (TD-DFT). The Coulomb-attenuating approach (CAM-B3LYP) was utilized to obtain theoretical electronic absorption spectra with the 6-31G(d, p) basis set to be more accurate than alternative quantum chemical calculation approaches, showing good agreement with the experimental data. The TDM and FMO investigation showed that glycine/CaO model has the highest TDM (10.129Debye) and lowest band gap (1.643 eV). The DFT computed IR and the experimental FTIR are consistent. The calculated UV-vis spectra showed a red shift with an increase in polarity following an increase in the absorption wavelength due to the interaction with ZnO, MgO, and CaO. Among the five solvents of water, methanol, ethanol, DMSO and acetone, the water and DMSO enhances the UV-Vis absorption. Glycine/CaO model showed high linear polarizability (14.629 × 10−24esu) and first hyperpolarizability (23.117 × 10−30esu), indicating its potential for nonlinear optical applications. The results showed that all model molecules, particularly glycine/CaO, contribute significantly to the development of materials with potential NLO features for sensor and optoelectronic applications. Additionally, MESP confirmed the increased electronegativity of the studied structures. Additionally, glycine/ZnO nanocomposite was synthesized and characterized using IR and UV-visible spectroscopy to determine their structural and spectroscopic features. It was discovered that there was good agreement between the DFT computed findings and the related experimental data. The antibacterial activity of glycine/ZnO nanocomposites against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa were studied in terms of concentration and time. The results showed that increasing the concentration of glycine/ZnO nanocomposite significantly enhanced its antibacterial efficacy by lowering optical density. Notably, Pseudomonas aeruginosa exhibited lower susceptibility to the nanocomposite compared to S. aureus, requiring higher concentrations for effective bactericidal action. In summary, this study contributes novel insights into the dual functionality of glycine-metal oxide complexes, with significant implications as optical biosensor for microbial detection.
Progression of disease within 24 months (POD24) in multiple myeloma implicates poor prognosis and limitations of current prediction models for POD24
Authors: Cao Yongqin , Gong Yingying , Wang Qingqing , Xia Jun , Zhou Xin , Sun Chao
Published: October 2024

Multiple myeloma (MM) is a common hematological malignancy, and its prognostic factors have been extensively studied. Progression of disease within 24 months (POD24) suggests a poor prognosis in many malignancies, but is rarely mentioned in MM. This study aimed to investigate the prognostic value of POD24 in MM and risk factors of POD24, and to evaluate the predictive value of existing MM prognostic models for POD24. The research retrospectively analyzed the clinical data of MM patients and found that the occurrence of POD24 is an independent prognostic factor affecting overall survival in MM, while non-transplantion and genetic abnormality are independent risk factors for the occurrence of POD24. The existing prognostic models are not effective in predicting POD24. Therefore, it’s still necessary to explore a prognostic model that can predict POD24 more accurately.
Stochastic hexagonal injectors in artificial spin ice
Authors: Puttock Robert , Fondet Anaïs , Andersen Ingrid M. , Rosamond Mark C. , Fernández Scarioni Alexander , Schumacher Hans W. , Snoeck Etienne , Gatel Christophe , Kazakova Olga
Published: October 2024

Artificial spin ice (ASI) systems have emerged as powerful platforms for exploring the fundamental aspects of magnetic frustration and topological phenomena in condensed matter physics. In this study, we investigate the bountiful effects that result from introducing hexagonal magnetic defects into an ASI lattice. The stochastic stabilisation of a plethora of metastable states in the hexagonal defects are explored, as well as harnessing the defect magnetisation state for the selective injection of emergent monopoles of different polarities and proximities within the lattice. We demonstrate a mechanism for tailoring the ASI behaviour using the magnetic state of the defect, which is of interest to applications including magnetic memory devices and spin-based logic.
KMnO4/Pb staining allows uranium free imaging of tissue architectures in low vacuum scanning electron microscopy
Authors: Sawaguchi Akira , Kamimura Takeshi , Kitagawa Kyoko , Nagashima Yoko , Takahashi Nobuyasu
Published: October 2024

Scanning electron microscopy under low-vacuum conditions allows high-resolution imaging of complex cell/tissue architectures in nonconductive specimens. However, the conventional methods for metal staining of biological specimens require harmful uranium compounds, which hampers the applications of electron microscopy. Here, we introduce a uranium-free KMnO4/Pb metal staining protocol that allows multiscale imaging of extensive cell/tissue architectures to intensive subcellular ultrastructures. The obtained image contrast was equivalent to that of Ur/Pb staining and sufficient for ultrastructural observation, showing the fine processes of podocytes in the glomerulus, which were invisible by light microscopy. The stainability in the elastic tissue indicated that the distinct histochemical properties of KMnO4 oxidation led to Pb deposition and BSE signal enhancement superior to Ur staining. Elemental analysis clarified that the determinant of the backscattered electron signal intensity was the amount of Pb deposition enhanced by KMnO4 oxidation. This user-friendly method is anticipated to create a new approach for biomedical electron microscopy.
Recent progress in spin-orbit torque magnetic random-access memory
Authors: Nguyen V. D. , Rao S. , Wostyn K. , Couet S.
Published: October 2024

Spin-orbit torque magnetic random-access memory (SOT-MRAM) offers promise for fast operation and high endurance but faces challenges such as low switching current, reliable field free switching, and back-end of line manufacturing processes. We review recent advancements in perpendicular SOT-MRAM devices, emphasizing on material developments to enhance charge-spin conversion efficiency and large-scale device integration strategies. We also discuss the remaining challenges in achieving a single device with low switching current, reliable field free switching to unlock the full potential of SOT-MRAM technology.
Temporal signal processing with nonlocal optical metasurfaces
Authors: Cotrufo Michele , Esfahani Sedigheh , Korobkin Dmitriy , Alù Andrea
Published: October 2024

Nonlocal metasurfaces have recently enabled an ultra-compact, low-power and high-speed platform to perform analog image processing. While several computational tasks have been demonstrated based on this platform, most of the previous studies have focused only on spatial operations, such as spatial differentiation and edge detection. Here, we demonstrate that metasurfaces with temporal nonlocalities – that is, with a tailored dispersive response – can be used to implement time-domain signal processing in deeply subwavelength footprints. In particular, we experimentally demonstrate a passive metasurface performing first-order differentiation of input signals with high-fidelity and high-efficiency. We also show that this approach is prone to scalability and cascaded computation. Our work paves the way to a new generation of ultra-compact, passive devices for all-optical computation, with applications in neural networks and neuromorphic computing.
Photocatalytic CO2 reduction to CO catalysed by lanthanide complexes
Authors: Zhao Yingzhe , Zhang Jianling , Wang Haoxiang , Zhang Renjie , Teng Yunan , Li Meiling , Song Yi , Tan Zhonghao
Published: October 2024

CO2 can be efficiently converted into CO under light irradiation with water as a sacrificial reagent, using a lanthanide complex as a photocatalyst.
Europium doping promoted intermolecular charge transfer in UiO-67-CDC for ultrasensitive turn-on colorimetric detection of an anthrax biomarker
Authors: Liu Ming-Cheng , Du Jia-Qi , Sun Qian , Gao En-qing
Published: October 2024

We have synthesised a lanthanide MOF, Eu@UiO-67-CDC, for the sensitive detection of DPA, offering a practical, instrument-free sensing solution.
Electrofluorochromism based on the valence change of europium complexes in electrochemical devices with Prussian blue as the counter electrode
Authors: Yabuta Ryoto , Kobayashi Norihisa , Nakamura Kazuki
Published: October 2024

Electrochemical luminescence control of Eu complexes was improved using electrochromic Prussian blue films.
Comprehensive untargeted lipidomic profiling of third generation lentiviral vectors and packaging cells
Authors: Roberts Joshua A. , Godbout Elena , Menard Jocelyn A. , Boddy Christopher N. , Diallo Jean-Simon , Smith Jeffrey C.
Published: October 2024

A novel LCMS workflow to elucidate the lipid composition of lentiviral vectors and measure the lipidomic impact of their production.
A stochastic photo-responsive memristive neuron for an in-sensor visual system based on a restricted Boltzmann machine
Authors: Kim Jin Hong , Kim Hyun Wook , Chung Min Jung , Shin Dong Hoon , Kim Yeong Rok , Kim Jaehyun , Jang Yoon Ho , Cheong Sun Woo , Lee Soo Hyung , Han Janguk , Park Hyung Jun , Han Joon-Kyu , Hwang Cheol Seong
Published: October 2024

This work implements a photo-responsive stochastic neuron as an input neuron in an in-sensor restricted Boltzmann machine (RBM).
Discovery of Schiff bases as potent antibacterial and antifungal agents
Authors: Obradović Radojko , Joksimović Nenad , Janković Nenad , Kosanić Marijana , Matić Jovana , Milović Emilija , Bogdanović Goran A. , Petronijević Jelena
Published: October 2024

Schiff bases as potent inhibitors of microorganisms growth.
Mesoscopic spiral nanoplates formed by porphyrin-spaced coordination frameworks for enhanced H2O2 photosynthesis
Authors: He Liang , Chen Er-Xia , Xiang Ju-Qiang , Guo Yu-Jun , Zhang Jian , Lin Qipu
Published: October 2024

Two-dimensional chiral bismuth–porphyrin metal–organic frameworks featuring mesoscopic square spiral terrace morphology significantly enhance H2O2 photosynthesis.
Electrochemical diversification of cysteine derivatives and cysteine-containing peptides to phosphorothioates and sulfinates
Authors: Xiao Longyu , Li Yifan , Huang Jun , Pan Li , Wu Pan , Weng Yue
Published: October 2024

This study explores the application of modified cysteine in oligopeptides to overcome challenges in amino acid residue modification, with a focus on cysteine.
Introducing co-review to RSC Advances
Authors: Fisher Laura , Cox Russell J. , Faulds Karen
Published: October 2024

RSC Advances now offers the option of co-review for our reviewers. Editors-in-Chief Russell J. Cox and Karen Faulds, and Executive Editor Laura Fisher, offer more detail on how this will work.
Yeast bio-batteries
Authors: Crespilho Frank N. , Brito-Pereira Ricardo , Policia Rita , Pereira Nelson , Sedenho Graziela C. , Costa Carlos M. , Lanceros-Méndez Senentxu
Published: October 2024

We present a fully rechargeable, eco-friendly bio-battery powered by Saccharomyces cerevisiae on recyclable PET electrodes, with high cyclability and promising applications in sustainable energy solutions for low-power devices.
Small‐signal stability criterion of the PMSG‐based wind power delivery system via VSC‐HVDC
Authors: Li Qiao , Wu Linlin , Wang Xiao , Wang Haifeng
Published: October 2024

This paper presents an analytical examination of the small‐single stability (SSS) criterion of the permanent magnet synchronous generator (PMSG)‐based wind power delivery system via voltage source converter‐based high voltage direct current (VSC‐HVDC). First, a small‐signal model of the PMSG‐based WPDS is developed. Then, the SSS criterion, driven by the phase‐locked loop of the PMSG in the sub‐synchronous timescale, is derived. The derived SSS criterion provides analytical insights into why and how the loading condition, the grid connection, and the control parameters affect the system’s SSS. It is unambiguously revealed that increasing loading conditions of the PMSG or/and the grid connection of the WPDS to VSC‐HVDC shall bring about a higher risk of oscillatory instability. Hence, analytical derivation of the SSS criterion helps better understand the instability mechanism in the PMSG‐based WPDS via VSC‐HVDC. In addition, while the derivation of the SSS criterion presupposes identical dynamics among PMSGs, this derived criterion can still be approximately utilized to assess the SSS of the PMSG‐based WPDS via VSC‐HVDC, irrespective of whether the dynamics of the PMSGs are similar or different. Finally, the SSS criterion is demonstrated and evaluated through three examples of the PMSG‐based WPDS via VSC‐HVDC.
Image quality and radiation dose from pediatric abdomen-pelvis CT scans
Authors: Keshtkar M. , Sadeghi Moghadam M.
Published: October 2024

Introduction: The aim of this study is to assess the organ doses, effective dose, image quality, and the potential risk of developing radiation-related cancer in children undergoing computed tomography (CT) scans of the abdomen-pelvis.
Methods: The research involved 219 pediatric patients (129 males and 90 females) who underwent an abdomen-pelvic CT examination. The patients were categorized into four age groups: <1, 1-4, 5-9, and 10-14 years old. The NCICT software version 3.0 was utilized to estimate the organ doses and effective dose. Estimation of cancer incidence risks were conducted according to the Biological Effects of Ionizing Radiation (BEIR) VII report. The image quality was evaluated by measuring the level of noise, as well as the signal-to-noise ratio, and contrast-to-noise ratio.
Results: The colon received the highest organ dose in all age groups. The risk of all cancers was 75.38 per 100,000 for the <1 age group, and it decreased to 56.10 for the 10-14 age group. The cancer risks were statistically higher for females (p < 0.05). The mean noise values for the liver, aorta, and paraspinal muscle were found to be 9.08, 11.04, and 8.21, respectively.
Conclusion: The findings of present study indicate that pediatric abdomen-pelvis CT examinations carry a potential risk of cancer that should not be disregarded. Consequently, it is crucial to prioritize radiation protection measures in children compared to adults.
Triangular Fibrocartilage Complex (TFCC) – Anatomy, Imaging, and Classifications with Special Focus on the CUP Classification
Authors: Schmitt Rainer , Kunz Andreas Steven , Reidler Paul , Huflage Henner , Hesse Nina
Published: October 2024

The TFCC consists of several components whose functional significance has been recognized in detail in recent years. Existing classifications are partly incomplete. In addition, the TFCC requires specific and dedicated imaging techniques.

This review describes the anatomy and pathoanatomy of the TFCC. The different types of TFCC lesions on MRI as well as MR and CT arthrography are explained and compared with the current literature. In addition, the novel CUP classification is presented and illustrated with image examples.

Anatomically and functionally, the articular disc and radioulnar ligaments with their ulnar insertions and the inhomogeneously structured TFCC periphery must be differentiated. For accurate imaging, thin slices with high in-plane resolution and techniques to optimize contrast are required. Plain MRI is exclusively dependent on T2 contrast, while gadolinium-enhanced MRI offers the additional benefit of focal contrast enhancement, e.g., of fibrovascular repair tissue at the lesion site. However, the reference standard continues to be MR and CT arthrography, which should be used for focused indications. The CUP classification, which allows a comprehensive description and categorization of TFCC lesions, is presented and illustrated.
Design of a gamma threshold detector based on the bubble chamber for high-flux gamma beams
Authors: Yu Yong , Zhu Wenjun , Ouyang Xiaoping
Published: October 2024

The detection of high-flux gamma beams from laser plasma interactions is always hampered by signal pileup. In this study, a gamma threshold detector based on the bubble chamber is designed to detect high-flux gamma beams. Through simulations, it has been demonstrated that this detector can detect gamma rays with energies above 5 MeV through photonuclear reactions, even at fluences as high as 1011 photons/cm2. In addition, by setting the detection threshold at 0.1 MeV/μm, a yield of up to 10−2 bubbles per gamma interaction can be achieved. Finally, the bubble chamber in the detection of a gamma ray from the inverse Compton scattering process is also discussed.
Skyrmion dynamics in attractive and repulsive local magnetic fields
Authors: Reimers Leo , Schäffer Alexander F. , Vedmedenko Elena Y. , Lo Conte Roberto
Published: October 2024

The study of the behavior of magnetic skyrmions in local magnetic fields’ nanometric length-scale has gained increasing interest in recent years due to the theoretical proposal of magnetic skyrmion–superconducting vortex pairs as potential hosts for topologically protected bound states, which hold high promise for applications in quantum computing. From a magnetic interaction point-of-view, the key interest lies in understanding the skyrmion dynamics triggered by the magnetic energy landscape generated by the superconducting vortex. Here, we present a micromagnetic study of the dynamics of nanometric skyrmions inside a Gaussian magnetic field profile, which is used as a simplified version of the vortex magnetic flux. On the one hand, our calculations show that local non-linear magnetic fields can be very effective in controlling the dynamics of magnetic skyrmions; in particular, they offer the appealing possibility to manipulate skyrmions in a two dimensional space. On the other hand, they also show that the dynamics of a skyrmion in a local magnetic field can be manipulated via a uniform external magnetic field without any change in the magnetic field gradient. An analytical expression for the skyrmion velocity is given, and the corresponding microscopic dynamics are confirmed by the micromagnetic simulations. This work is expected to motivate more theoretical and experimental studies of the behavior of magnetic skyrmions in proximity to superconducting vortices.
Evidence and engineering of x-ray luminescence in lead free perovskite Cs2AgInCl6 with Bi substitutions
Authors: Siddique Hassan
Published: October 2024

Cs2AgInCl6 belongs to the family of lead-free halide double perovskites. Lead-free halide double perovskite appears as a viable contender for scintillator applications due to its inexpensive production costs, low intrinsic trap density, and nanosecond quick reaction. Perovskite crystals have a substantially lower trap density than lead halide and traditional oxide scintillator materials, according to thermo-luminescence measurements. Cs2AgInCl6 structure and dimensionality were engineered by Bi doping. Bi substitution reduces the bandgap, making it suited for scintillation applications. Bi substitution allows for easy tuning of Cs2AgIn(1−x)BixCl6 (0 ≤ x ≤ 50) due to its wide versatility in scintillation properties. For Cs2AgIn(1−x)BixCl6 (0 ≤ x ≤ 50), x-ray power dependent luminescence increases with increasing power. Because of their nontoxicity, sensitivity, reaction time, and stability, Cs2AgIn(1−x)BixCl6 (0 ≤ x ≤ 50) double perovskite crystals are promising for x-ray scintillation.
Soft x-ray tomography on the high field spherical tokamak ST40
Authors: Colgan C. , Bohlin H. , Buxton P. F. , Harryman D. M. , Jones O. , Lowe H. F. , Naylor G. , O’Gorman T. , Pyragius T. , Sertoli M. , Sladkomedova A. , Sridhar S. , Thwaites R.
Published: October 2024

As part of its roadmap to developing commercial fusion plants, Tokamak Energy Ltd. operates the high field spherical tokamak ST40. Studies on this device will help to expand the high field spherical tokamak physics basis by characterizing confinement and the fusion triple product. In support of this, bolometers and broadband and x-ray sensitive diodes can provide information on key energy loss mechanisms of the plasma. These mechanisms include core magnetohydrodynamic activity that deteriorates confinement, such as sawtooth crashes that can be used to characterize relaxations in the q-profile. In addition, combinations of these diagnostics can be used to infer the total radiated power losses and plasma composition. Here, we present results from a new, midplane, tangential, Be-filtered diode with 16 channels spanning the radial extent of the plasma. The system is shown to resolve magnetohydrodynamic instabilities (up to 100 kHz) and be able to provide radiation profiles through tomography. The tomographic inversion routine is compared against other diagnostics on ST40 and provides emissivity measurements across a variety of operating scenarios. Finally, we look ahead to implementing multiple soft x-ray cameras on ST40 and the improvements this will have on the diagnostic capabilities.
Identifying extreme events in the stock market: A topological data analysis
Authors: Rai Anish , Nath Sharma Buddha , Rabindrajit Luwang Salam , Nurujjaman Md. , Majhi Sushovan
Published: October 2024

This paper employs Topological Data Analysis (TDA) to detect extreme events (EEs) in the stock market at a continental level. Previous approaches, which analyzed stock indices separately, could not detect EEs for multiple time series in one go. TDA provides a robust framework for such analysis and identifies the EEs during the crashes for different indices. The TDA analysis shows that L1, L2 norms and Wasserstein distance (WD) of the world leading indices rise abruptly during the crashes, surpassing a threshold of μ+4∗σ, where μ and σ are the mean and the standard deviation of norm or WD, respectively. Our study identified the stock index crashes of the 2008 financial crisis and the COVID-19 pandemic across continents as EEs. Given that different sectors in an index behave differently, a sector-wise analysis was conducted during the COVID-19 pandemic for the Indian stock market. The sector-wise results show that after the occurrence of EE, we have observed strong crashes surpassing μ+2∗σ for an extended period for the banking, automobile, IT, realty, energy, and metal sectors. While for the pharmaceutical and FMCG sectors, no significant spikes were noted. Hence, TDA also proves successful in identifying the duration of shocks after the occurrence of EEs. This also indicates that the banking sector continued to face stress and remained volatile even after the crash. This study gives us the applicability of TDA as a powerful analytical tool to study EEs in various fields.
Experimental study on vortex-induced vibrations of double-hanger cable: Upstream wake flow induces downstream vibrations
Authors: Lang Tianyi , Wang Hao , Gao Hui , Xu Zidong
Published: October 2024

This study is inspired by an experimental observation for vortex-induced vibrations (VIVs) of a double-hanger cable system, in which a smaller vibration of the downwind hanger cable is re-excited over a narrow range of wind speeds beyond the “lock-in” range. This phenomenon is known as the wake vortex-induced vibrations (WVIVs), where the upstream wake flow induces downstream vibrations. To further investigate the characteristics and reasons for WVIVs, a refined wind tunnel test of double-hanger cable was conducted to consider the influence of aerodynamic interaction. The double-hanger cable was modeled by the tandem-arranged spring-mounted cylinders vibrating in two dimensions. The vibration responses of hanger cables were obtained under various wind speeds to reproduce the lock-in phenomenon. In addition, the vibration trajectory, phase relationship, damping ratio, inter-cable correlation, and the wind pressure on the surface of cables were analyzed. Finally, the Stockbridge dampers were designed to suppress the vibrations. The results show that under the aerodynamic interaction of the cables, the onset wind speed of VIVs in the double cables increases, and the downstream cable WVIVs closely follow the VIVs. During the WVIV phase, the downstream cable behavior is characterized by increased negative aerodynamic damping and an inverse displacement correlation between the cables. The phase relationships between the cables are time-varying due to the aerodynamic interaction. The first proper orthogonal decomposition mode of wind pressure dominates the cross-wind of motions and is crucial in vibrations. Stockbridge dampers can effectively reduce the amplitude of VIVs and eliminate WVIVs in cables.
Enhancement of OH spectra in atmospheric pressure plasma jet by femtosecond laser
Authors: Lee Wonwook , Tran Tuyen Ngoc , Hwang Juil , Lee Kwang-Geol , Kim Hyungsik , Jung Woohyun , Lee Kisang , Oh Cha-Hwan
Published: October 2024

A helium (He) atmospheric pressure plasma jet (APPJ) system with a single electrode was configured. A pulsed light of femtosecond (fs) laser was irradiated at the guided streamer of He APPJ through an objective lens to generate the laser induced plasma (LIP) inside the He APPJ. The optical emission spectra of LIP were measured as the light energy of the fs laser increased. The spectra of hydroxyl molecules and atomic oxygen were enhanced when the fs laser energy exceeded 114 μJ. The plasma parameters of LIP inside the APPJ were determined using He collisional-radiative model. Electron temperature and density increased to ∼7.2 eV and 1.7×1014 cm−3, respectively. The dominant processes underlying the enhancement were discussed in the interaction of fs laser and He APPJ.
Inertial migration of cylindrical micelles formed by comb-like copolymer in Poiseuille flow
Authors: Lin Mingtao , Shi Qingfeng , Yang Xiang , Ding Mingming
Published: October 2024

By combining the lattice Boltzmann model of fluid flow with the molecular dynamics model of copolymers, we investigate the inertial migration of cylindrical micelles, which is obtained by controlling the length ratios of hydrophilic and hydrophobic segments in a comb-like copolymer. Our results demonstrate that cylindrical micelles gradually deviate from the center of the nanochannel with increasing Reynolds number (Re). For the same Re, the larger the cylindrical micelle is, the closer it is to the center of the nanochannel. Importantly, we find that the change in the equilibrium position is particularly pronounced at Re less than 0.1, while the trend becomes smoother at Re greater than 0.1, which is because of the transition of micelles from cylindrical to disk-like shapes when Re is smaller than 0.1, and does not change as Re further increases. This work provides an understanding of cylindrical micelles' inertial migration, particularly in identifying the effect of morphological changes on the equilibrium position, which could lead to significant advancements in the inertial migration of polymer micelles.
Prediction of blastocyst formation based on fusion of morphokinetic and morphological features
Authors: Du Yue , Wang Ruipeng , Liu Yaowei , Zhao Qili , Sun Mingzhu , Zhao Xin , Shi Junsong
Published: October 2024

The transition from a highly subjective morphological assessment to time-lapse imaging improves the accuracy of predicting embryonic developmental potential. In actual operations, embryos are cultured for 2–3 days in a time-lapse monitoring system before being transferred to recipients. However, most existing prediction models require videos or images spanning a five-day period. Therefore, it is necessary to develop a method that accurately predicts blastocyst formation given input data spanning only 2–3 days. In this study, we propose a method for predicting blastocyst formation using early morphokinetic and morphological parameters prior to the five-cell stage. We employed a YOLOv5 pretrained deep-learning network to recognize the first four-cell stages for the accurate extraction of morphokinetic parameters and used these parameters as inputs to construct four long short-term memory-based morphokinetic models for blastocyst formation prediction, obtaining the best area-under-the-curve (AUC) value of 0.7297 [0.669–0.884]. We then extracted the three frames before and after the t1–t4 time points and calculated the image entropy and gray-level co-occurrence matrix entropy as morphological features to build a prediction model. This model was subsequently fused with the morphokinetic model, and an AUC of 0.8325 [0.7601–0.9067] was achieved. Our results have implications for automatic embryo screening given information on early embryonic development.
Accurate nuclear quantum statistics on machine-learned classical effective potentials
Authors: Zaporozhets Iryna , Musil Félix , Kapil Venkat , Clementi Cecilia
Published: October 2024

The contribution of nuclear quantum effects (NQEs) to the properties of various hydrogen-bound systems, including biomolecules, is increasingly recognized. Despite the development of many acceleration techniques, the computational overhead of incorporating NQEs in complex systems is sizable, particularly at low temperatures. In this work, we leverage deep learning and multiscale coarse-graining techniques to mitigate the computational burden of path integral molecular dynamics (PIMD). In particular, we employ a machine-learned potential to accurately represent corrections to classical potentials, thereby significantly reducing the computational cost of simulating NQEs. We validate our approach using four distinct systems: Morse potential, Zundel cation, single water molecule, and bulk water. Our framework allows us to accurately compute position-dependent static properties, as demonstrated by the excellent agreement obtained between the machine-learned potential and computationally intensive PIMD calculations, even in the presence of strong NQEs. This approach opens the way to the development of transferable machine-learned potentials capable of accurately reproducing NQEs in a wide range of molecular systems.
Effects of wind barriers on the aerodynamic forces and driving safety of vehicles on a wide bridge girder at various angles of attack
Authors: Li Ming , Lin Zhongyu , Dai Rui , Wang Yuxia , Li Mingshui
Published: October 2024

This paper presents the effects of angles of attack (AOA) on the windproof effect of wind barriers and the driving safety of highway vehicles on a wide bridge girder. The aerodynamic force coefficients of the vehicles were obtained using the force measurement technique. Computational fluid dynamics simulations were employed to investigate the mean wind velocity field on the upper surface of the girder. A comparison was made between the aerodynamic forces on a vehicle at various AOA on a bridge deck with guardrails and a deck with wind barriers. The windproof effect of wind barriers at various AOA was accessed by the safety factor of a vehicle. The results showed that the maximum of the aerodynamic forces of vehicles was not typically observed at a 0° AOA. The windproof effect of wind barriers became more pronounced as the magnitude of the AOA increased. As AOA increases, the height of the low wind velocity zone above the deck shows an upward trend. Compared to the deck with the guardrails, the height of the low wind velocity zone was much higher in the presence of wind barriers. The increase in the height of the low wind velocity zone will result in a decrease in the aerodynamic side force and an increase in the rolling moment acting on vehicles. It is also noteworthy that the installation of wind barriers can cause a reduction of overturning and side-slip safety factors of vehicles at specific AOA. This suggests that the wind barrier may potentially compromise driving safety at specific AOA.
A finite-temperature study of the degeneracy of the crystal phases in systems of soft aspherical particles
Authors: Pini Davide , Weißenhofer Markus , Kahl Gerhard
Published: October 2024

We employ classical density-functional theory to investigate the phase diagram of an assembly of mutually penetrable, parallel ellipsoids interacting via the generalized exponential model of index four (GEM-4) pair potential. We show that the crystal phases of the system are obtained from those of the spherically symmetric GEM-4 model by rescaling the lattice vectors. Performing this rescaling in combination with an arbitrary rotation of the lattice leads to infinitely many different structures with the same free energy, thereby implying their infinite degeneracy. These findings generalize to non-zero temperature the results formerly obtained by us [Pini et al., J. Chem. Phys. 153, 164901 (2020)] for the ground state of a similar system of ellipsoids interacting via a Gaussian potential. According to the mean-field free-energy functional used here, our conclusions apply to soft-core potentials both when they form cluster crystals as the GEM-4 and when they form single-occupancy crystals as the Gaussian itself.
Deflection and drag on flexible marine structures in steady currents and internal solitary waves
Authors: Sun Hongwei , You Yunxiang , Lei Jiarui
Published: October 2024

This study investigates the deflection and drag on flexible marine structures under steady-flow conditions and internal solitary waves (ISWs) using free-hanging risers as a representative example. We examine the relationship between the Cauchy number (Ca), buoyancy parameter (B), deflected height (hd), and effective length (le). Our findings reveal that flow fields influenced by ISWs closely resemble steady flow. This similarity enables the use of steady-flow analyses as a proxy in extreme motion studies of flexible marine structures. We also discover that an inclined configuration of flexible marine structures, such as free-hanging risers, diminishes the horizontal forces exerted by both steady currents and ISWs. Additionally, for both scenarios, increasing the weight of longer flexible marine structures is more effective than increasing stiffness in reducing deflection. The proposed method accurately predicts the deformation of flexible marine structures caused by ship motion in deep-sea mining and the movements of ocean risers with floating platforms. This finding is important for the design and optimization of these structures.
Aerodynamic characteristics of tall building with wind turbines at corners
Authors: Wang Zhuoran , Chen Wenliang , Hong Hao , Hu Gang
Published: October 2024

This study experimentally investigates the impact of a pair of vertical-axis wind turbines at the leading corners of a tall building on its aerodynamic characteristics. These wind turbines have the potential to serve dual purposes: harnessing wind energy under normal wind conditions and mitigating wind loading of the building under strong wind conditions. The wind tunnel testing results in this study indicate when the tip speed ratio of the turbines is 0.34, with the wind turbines rotating toward downstream, the standard deviation of lift coefficient of the building decreases by 30.9%. Meanwhile, the mean pressure coefficient and the standard deviation of pressure coefficient on both the side face and leeward face of the building also exhibit a certain degree of reduction. The peak value of the power spectral density of lift coefficient of the building is also significantly decreased. This study clearly demonstrates that the wind turbines at the leading corners of tall buildings have the potential to effectively reduce wind loading of the buildings.
Investigation of combustion mode conversion driven by fuel flow variation in a cavity-based scramjet
Authors: Li Le , Wan Minggang , Sun Mingbo , Tian Yifu , Zhu Jiajian
Published: October 2024

This work aimed to investigate combustion mode conversions by rapid variation of the fuel flow rate in a cavity-based scramjet combustor. The experiments were carried out on a direct-connected facility with an inflow condition of Mach number 2.52, a total pressure of 1.35 MPa, and a total temperature of 1650 K. The fuel injector consisted of two injection ports: fuel was continuously injected from one port while the other controlled the fuel flow for mode conversions by switching it on or off. Simultaneous schlieren and CH* imaging techniques were used to characterize the dynamics of combustion mode conversions. It was recognized that the combustion modes characterized by different flow field structures and heat release distributions can be classified into three types: the shear-layer mode, the transition mode, and the jet-wake mode. During the combustion mode conversion, the mixing region of the transverse jet and air became thicker with the increase in fuel flow rate, and the gradient of the flow field density and the flame area increased, making the flame more likely to propagate upstream. The combustion suppression induced by rapid fuel addition was observed at low equivalence ratios. It was speculated that the weak heat supply was insufficient to provide adequate heat for the rapid ignition of the added fuel. Furthermore, it was found that the flame-flow matching process with frequent flame propagation upstream occurred during the combustion mode conversion. This process was attributed to the mismatch between the increasing heat release and the original flow field structure.
An improved two-phase rate transient analysis method for multiple communicating multi-fractured horizontal wells in shale gas reservoirs: Field cases study
Authors: Bai Wenpeng , Cheng Shiqing , Wang Qingkai , Guo Qiao , Guo Xinyang , Wang Yang
Published: October 2024

The reduction in well spacing for multi-fractured horizontal wells (MFHWs) and the increase in infill drilling exacerbate the risk of fracture communication. This presents substantial challenges for the rate transient analysis of the parent–child well system. This study proposes an improved two-phase straight-line analysis method to evaluate the linear flow parameters of multiple communicating MFHWs in shale gas reservoirs. Considering shale gas adsorption–desorption mechanisms, nonuniform length of fractures, stress-dependent effects, and matrix shrinkage effects, two-phase productivity equation is established within the dynamic drainage area (DDA). Subsequently, we develop a three-well square root of time plot based on DDA correction and propose a rigorous workflow for evaluating linear flow parameters in single-well, two-well, and three-well systems. The straight lines on the parent well's square root of the time plot exhibit varying degrees of jumps, depending on the frequency of fracture communication. After communication, it is necessary to adjust the cumulative production and production time of the parent well to accurately recalculate the average pressure within the drainage area. Numerical simulations are employed to generate a series of cases under different reservoir conditions to validate the accuracy of the proposed model. The results show that the model estimates fracture half-lengths with errors within 8%, meeting the precision requirements for field applications. Additionally, the method exceeds numerical simulations in computational speed. Two field case studies in the WY Basin, China, further illustrate the effectiveness and practicality of the proposed method, providing theoretical support for hydraulic fracturing construction design and development planning.
Investigation of the double layer structure of 1-butyl-3-methylimidazolium thiocyanate at the air–water interface using sum-frequency generation vibrational spectroscopy
Authors: Wang Baihui , Duan Yiyi , Bai Yimin , Zhang Weiting , Peng Jiahui , Bian Hongtao
Published: October 2024

The interfacial structure and adsorption behavior of 1-butyl-3-methylimidazolium thiocyanate ionic liquids (ILs) aqueous solutions were investigated using sum-frequency generation vibrational spectroscopy (SFG-VS) and surface tension measurements. Polarization-dependent measurements revealed a dramatic increase in the SFG signal for both CH and CN stretching modes with increasing ILs concentration, reaching a maximum at a mole fraction of 0.01. This concentration dependence was accompanied by a dramatic drop in surface tension. Upon further increasing the concentration, surface tension varied slightly and reached a constant value, while the SFG signal decreased significantly. Quantitative polarization analysis showed that as the bulk concentration increased, the apparent molecular orientation of the SCN− transition dipole at the interface changed from 51° to 46°, and the tilt angle of CH3 group of the butyl chain attached to the imidazole cationic ring changed from 18° to 32°. The decrease in the SFG signal can be explained by the formation of a double layer adsorption structure at the air/water interface. It was also demonstrated that the anions were adsorbed at the interface simultaneously with the cationic group, rather than by successive adsorption as proposed in a previous study. Using the Shereshefsky model, the thermodynamic Gibbs free energy of adsorption deduced from surface tension data was compared with SFG results.