bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of EUS-guided keyhole biopsies in diagnosing subepithelial lesions of the upper gastrointestinal tract
Authors: Verhoeve Sen , Verloop Cynthia , Bruno Marco , Terpstra Valeska , Van Driel Lydi , Perk Lars , Hol Lieke
Published: October 2024

Background and study aims Tissue acquisition is required for diagnosis of subepithelial lesions (SELs). However, obtaining adequate tissue remains challenging. This study investigated an EUS-guided technique using a forceps to create a channel and take multiple biopsies from the center of the lesion, therefore called endoscopic ultrasound-guided keyhole biopsy (EUS-KB).

Patients and methods A retrospective cohort study was conducted in 56 patients with SELs in the upper gastrointestinal tract who were scheduled to undergo EUS-KB. The primary aim was to assess diagnostic yield, defined as the percentage of procedures where EUS-KB resulted in a definitive histopathological diagnosis. Furthermore, factors influencing diagnostic yield were investigated. Additional outcomes included technical success and adverse events.

Results Technical success was achieved in 55 of 60 biopsies (91.7%). EUS-KB provided a diagnosis in 44 of 55 biopsies (80.0%), histology mostly showing gastrointestinal stromal tumor or leiomyoma. The diagnostic yield was not significantly influenced by the size or location of the SEL. Adverse events occurred in one patient (1.7%).

Conclusions EUS-KB is a feasible and safe technique for obtaining a classifying diagnosis for SELs in the upper gastrointestinal tract. It could offer an alternative diagnostic modality, especially in lesions smaller than 20 mm.
Tyrosine Kinase Inhibitor Induced Proteinuria – A
Review
Authors: Gayathri J S. , Krishna S. Swathi , Rakesh M. P.
Published: October 2024

Tyrosine Kinase inhibitor (TKI) is a class of drugs that interfere with protein
kinasesʼ signal transduction pathways through an array of inhibitory mechanisms.
Tyrosine kinases (TK) have an inevitable role in downstream signal transduction
and the proliferation of tumour cells. Hence, tyrosine kinase inhibitors (TKIs)
are frequently employed as anti-neoplastic agents in the treatment of colon,
breast, kidney, and lung cancers. They can be used as single or combination
therapy with other targeted therapies. It is understood that TKIs pose a risk of
developing proteinuria in some patients as it can primarily result in
dysfunction of the split diaphragm, constriction or blockage of capillary lumens
mediated by the basement membrane, acute interstitial nephritis, or acute
tubular necrosis. This paper reviews the mechanism of action of TKIs, the
pathophysiological mechanism of TKI-induced proteinuria, and its management
Fig. 1
Radiographic Diagnosis of Osteoporotic Vertebral Fracture in Older Women and Men Based on Statistical Probability
Authors: Wáng Yì Xiáng J.
Published: October 2024

A radiographic gold standard to distinguish osteoporotic vertebral fractures (VFs) from nonosteoporotic VFs does not exist. Radiographic fracture-shaped vertebral deformity (FSVD) is common among young populations with normal bone strength. FSVD in an older population is called osteoporotic-like vertebral fracture (OLVF) when the FSVD is likely associated with compromised bone strength. For more severe grade deformities or when a vertebra is collapsed, experienced readers can make an osteoporotic VF diagnosis with a high degree of certainty. In milder cases, radiographic osteoporotic VF is often diagnosed based on a high probability rather than an absolute diagnosis. For older women, three nonadjacent minimal grade OLVFs (< 20% height loss), one minimal grade OLVF and one mild OLVF (≥ 20∼25% height loss), or one OLVF with ≥ 25% height loss meets the diagnosis of osteoporosis. For older men, a single OLVF with ≥ 33 to 40% height loss is insufficient to suggest the patient has osteoporosis.
Inflammatory Pseudotumor of the Ulnar Nerve Mimicking a Malignant Peripheral Nerve Sheath Tumor: A Radiologic Puzzle
Authors: Abelkis Eimantas , van Langevelde Kirsten , Doeleman Thom , Groen Justus , Navas Cañete Ana
Published: October 2024

Inflammatory pseudotumor (IPT) of a peripheral nerve is a rare non-neoplastic tumefactive inflammatory condition, often mimicking malignancy. The etiology of this condition is still unknown. Clinically and radiologically, the lesion can mimic a malignant tumor. This case report represents, as far as we know, the first publication describing the ultrasonography findings and the results of advanced dynamic contrast-enhanced magnetic resonance imaging (MRI) and diffusion-weighted MRI of IPT in a peripheral nerve. Suspicion of this entity on imaging can speed up the definitive diagnosis and potentially avoid overly radical treatment.
Bone Marrow and Metabolic Bone Disease
Authors: Aparisi Gómez Maria Pilar , Bazzocchi Alberto
Published: October 2024

The bone marrow represents one of the largest organs in the body, with a relevant metabolic role that continues to be investigated. Numerous studies have focused on marrow adipose tissue (MAT). Evidence indicates that the bone marrow adipocytes do not only work as storage tissue but also consist of endocrine and paracrine cells, with the potential to contribute to local and systemic metabolism. MAT plays a role in bone health through its interaction with the other components of bone. Many metabolic disorders (osteoporosis, obesity, diabetes) have a complex and still not well-established or understood relationship with bone health. This article surveys the literature on the relationship of bone marrow and metabolic disorders, and how it is being studied using imaging techniques, with a special focus on bone health.
Update on Quantitative Computed Tomography
Authors: Cheng Xiaoguang , Wang Ling , Blake Glen M. , Guglielmi Giuseppe
Published: October 2024

Quantitative computed tomography (QCT) has important technical advantages for the measurement of bone mineral density, and the technique is well suited for both the diagnosis of osteoporosis and the monitoring of treatment. Its use deserves a wider application than at present. The use of QCT in both research and in the clinic has recently garnered increasing attention. In this review, we update the advances and application of QCT in the study of osteoporosis.
Opportunistic Screening of Bone Fragility Using Computed Tomography
Authors: Acevedo Julian B. Herrera , Lenchik Leon , Weaver Ashley A. , Boutin Robert D. , Wuertzer Scott
Published: October 2024

Opportunistic screening uses existing imaging studies for additional diagnostic insights without imposing further burden on patients. We explore the potential of opportunistic computed tomography (CT) screening for osteoporosis, a condition affecting 500 million people globally and leading to significant health care costs and fragility fractures. Although dual-energy X-ray absorptiometry (DXA) remains the gold standard for diagnosing osteoporosis, > 50% of fractures occur in individuals not screened previously with DXA. With recent advancements in technology, CT has emerged as the most promising tool for opportunistic screening due to its wide use and the ability to provide quantitative measurements of bone attenuation, a surrogate of bone mineral density.

This article discusses the technical considerations, calibration methods, and potential benefits of CT for osteoporosis screening. It also explores the role of automation, supervised and unsupervised, in streamlining the diagnostic process, improving accuracy, and potentially developing new biomarkers of bone health. The potential addition of radiomics and genomics is also highlighted, showcasing the synergy between genetic and imaging data for a more comprehensive understanding of osteoporosis pathophysiology and with it possible novel osteoporosis therapies. The future of opportunistic CT screening holds significant promise, with automation and advanced image processing ultimately enhancing patient care, reducing rates of osteoporotic fractures, and improving patient outcomes.
Role of Advanced Magnetic Resonance Imaging in Differentiating among Glioma Subtypes and Predicting Tumor-Proliferative Behavior
Authors: Ganesan Gunalan , Rangasami Rajeswaran , Chandrasekharan Anupama , Marreddy Sahithi , Ramachandran Rajoo
Published: October 2024

Objective Gliomas are a devastating and heterogeneous group of primary brain tumors. Previously, the source of glioma was undetermined. Recent literature indicates that neural stem cells, or progenitors, are proposed to be the source of glioma. The prognosis of different types of gliomas differs due to their various biological tissue types. Besides the histological grade, the two useful immunohistochemistry markers that show the tumor's biological behavior are isocitrate dehydrogenase (IDH) labeling and the Ki-67 labeling index. We sought to determine the magnetic resonance imaging (MRI) characteristics associated with IDH mutational status and ascertain whether MRI combined with IDH mutational status, can better predict the clinical outcomes of gliomas.

Materials and Methods This period study was conducted in the Department of Radiology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India for 5 years (May 2016–May 2021). The study cohort included 30 patients diagnosed with gliomas who underwent preoperative MRI followed by surgical resection and histopathological examination. Preoperative MRI images were done to assess qualitative tumor characteristics such as location, margin of tumor, extent, cortical involvement, cystic component, mineralization or hemorrhage, and contrast enhancement.

Discussion Differences in MRI features between IDH-mutant (MT) and IDH-wild-type (WT) groups were analyzed using the chi-square test for categorical variables and the Mann–Whitney U test for continuous variables. Statistical analysis was conducted using SPSS software.

Results Among the 30 patients evaluated, 18 had IDH-WT and 12 had IDH-MT type gliomas. Male predominance (73.33%) was noted in our study. Brainstem location, indistinct borders (83.33%), less cortical involvement (72.22%), less cystic changes (88.89%), more area of necrotic component (44.44%), significantly increased choline/creatine (Cho/Cr) ratio, and choline/N-acetyl aspartate (Cho/NAA) ratio favors IDH-WT tumors. Positive T2-fluid-attenuated inversion recovery mismatch sign is more frequently seen in IDH-MT (7/12; 58.33%) tumors than in IDH-WT (4/18; 22.22%) tumors. Whereas well-defined contours (66.67%), more cortical involvement (83.33%), more cystic changes (58.33%), and less area of necrotic component favor IDH-MT type tumors.

Conclusion MRI is a very promising and valuable tool for differentiating among glioma subtypes and predicting tumor-proliferative behavior in glioma cases. The combination of MRI characteristics with IDH mutation status enhances the predictive accuracy for clinical outcomes in glioma patients. This approach could potentially guide treatment planning and improve prognostic assessments.
Hereditary Transthyretin Amyloidosis Polyneuropathy
Authors: Qarni Taha , Moshe-Lilie Orly , Kaku Michelle C. , Karam Chafic
Published: October 2024

In the last decade, we have witnessed dramatic improvements in the diagnosis, workup, management, and monitoring of patients with hereditary transthyretin amyloidosis (ATTRv). Updated imaging techniques (e.g., 99mTc-PYP scan) are increasingly being used in place of tissue biopsies for confirmation of disease. Novel treatments now include antisense oligonucleotide and RNA interference drugs, whereas new applications such as CRISPR and amyloid antibodies are being studied for potential use in the future. These treatments have dramatically improved quality of life and increased survival in patients with ATTRv. Despite these breakthroughs, many challenges remain. Some of these challenges include early recognition and diagnosis of ATTRv, monitoring and initiation of treatment in asymptomatic or paucisymptomatic carriers, adequate treatment in people with mixed phenotype (i.e., cardiac and neurological), and the emergence of new phenotypes in people living longer with the disease (i.e., central nervous system and ocular complications). Research in those areas of deficit is ongoing, and in the future, we may have preventive therapies, better biomarkers, more efficient therapies for organs that we cannot currently target, and enhanced diagnostic techniques with the help of novel imaging techniques and artificial intelligence. In this review, we will summarize the current knowledge about polyneuropathy related to ATTRv and its management, discuss methods to improve early diagnosis and monitoring, and discuss emerging trends.
Less Common Mononeuropathies
Authors: Treidler Simona
Published: October 2024

Uncommon mononeuropathies are challenging to diagnose as they can mimic joint pathology, radiculopathies, or plexopathies. They are less easily diagnosed due to unfamiliarity with their clinical presentation, knowledge of anatomy, and less commonly used diagnostic studies. A careful history, physical examination, and electrodiagnostic evaluation can help identify these neuropathies in a timely manner to administer the best treatment for resolution of symptoms. Recent advances in ultrasound and magnetic resonance techniques are used to confirm clinical suspicion of peripheral neuropathy by clearly depicting the anatomy and pathology as well as describing findings that mimic mononeuropathy. It is important for neurology, orthopedic, rheumatology, emergency, and primary care physicians to be familiar with less common mononeuropathies.
Spurring Innovation in AAC Technology through Collaborative Dreaming and Needs Finding with Individuals with Developmental Disabilities Who Use AAC
Authors: Lorah Elizabeth R. , MacNeil Stephen , Zimmerman Tara , Rackensperger Tracy , Holyfield Christine , Caldwell Nicolette , Dragut Eduard C. , Vucetic Slobodan
Published: October 2024

Millions of individuals who have limited or no functional speech use augmentative and alternative communication (AAC) technology to participate in daily life and exercise the human right to communication. While advances in AAC technology lag significantly behind those in other technology sectors, mainstream technology innovations such as artificial intelligence (AI) present potential for the future of AAC. However, a new future of AAC will only be as effective as it is responsive to the needs and dreams of the people who rely upon it every day. AAC innovation must reflect an iterative, collaborative process with AAC users. To do this, we worked collaboratively with AAC users to complete participatory qualitative research about AAC innovation through AI. We interviewed 13 AAC users regarding (1) their current AAC engagement; (2) the barriers they experience in using AAC; (3) their dreams regarding future AAC development; and (4) reflections on potential AAC innovations. To analyze these data, a rapid research evaluation and appraisal was used. Within this article, the themes that emerged during interviews and their implications for future AAC development will be discussed. Strengths, barriers, and considerations for participatory design will also be described.
The interrelationships between corporate political activity and corporate environmental performance: the role of language diversity
Authors: Shoham Amir , Frynas Jedrzej George , Arslan Ahmad , Bazel-Shoham Ofra , Lee Sang Mook , Khan Zaheer , Tarba Shlomo
Published: October 2024

Language affects almost every aspect of management in multinational enterprises (MNEs) but little is known about the impact of language on environmental performance. Our study investigates how language diversity affects the environmental performance of MNEs worldwide. We show that the grammatical structure of a language – specifically the first pronoun drop – is an important factor explaining the environmental performance of firms. Our analysis of 4454 company-year observations suggests that MNEs operating in societies that permit the first pronoun drop tend to have better environmental performance. Furthermore, we explore the impact of linguistic structure on the relationship between environmental performance and corporate political activity (CPA). We find that using the first pronoun drop of the local language moderates the influence of CPA on firms’ environmental performance. Our study concludes that international managers must pay greater attention to the neglected role of language in implementing environmental initiatives.
Subgrid-scale model considering the inverse energy cascade using an artificial neural network
Authors: Liu Feng , Wu Zhuangzhuang , Lv Pengfei , Yang Wei , Chen Congcong , Xu Junfeng
Published: October 2024

For the closure of the subgrid-scale (SGS) stress tensor, an artificial neural network (ANN)-based SGS model that takes account of the inverse energy cascade in isotropic turbulence is developed. The data required for training this ANN-based SGS model are provided by direct numerical simulation of isotropic turbulence with an inverse energy cascade. Two input features, the root mean square of the rate-of-strain tensor and the product of the eigenvalues of the rate-of-strain tensor, are employed to characterize the inverse energy cascade. An a priori test reveals that the ANN-based model adequately predicts the SGS stress tensor in the backward energy transfer process, and the predictive capability of the gradient model is found to be slightly poorer than that of the ANN-based model, while that of the Smagorinsky model is not satisfactory. In comparison with the gradient model, the ANN-based model even predicts a few backward energy transfer events in the stage of excessive energy dissipation. In addition, the off-diagonal component of the SGS stress tensor, rather than the diagonal component, may be intimately associated with the inverse energy cascade. The ANN-based SGS model presented here is expected to provide inspiration for future investigations of the construction of SGS models that take account of the inverse energy cascade.
An algorithm for multi-target tracking in low-signal-to-clutter-ratio underwater acoustic scenes
Authors: Chen Qiang , Wang Pingbo , Wei Hongkai
Published: October 2024

To simplify the computational complexity of the Joint Probabilistic Data Association (JPDA) algorithm for multi-target tracking in low-signal-to-clutter-ratio underwater acoustic scenes, and to solve the problem of unstable tracking caused by poor measurement accuracy of active sonar, a trajectory information-based JPDA optimization algorithm (TJPDA) is designed to meet the real-time and stability requirements of practical engineering. The false alarm rate is reduced by accumulating correlated target trajectories in multiple frames, and the influence factor is introduced to modify the correlation probability and simplify the confirmation matrix splitting process. This effectively solves the problem of information combination explosion and trajectory divergence caused by adjacent target interference in low signal-to-clutter-ratio underwater acoustic scenes. The simulation results show that compared with the JPDA algorithm, the TJPDA algorithm not only improves target-tracking accuracy but also reduces computation time, making it more suitable for practical engineering applications.
Coexistence of linear and non-linear thermoelectricity in graphene-superconductor tunnel junctions
Authors: Bianco Federica , Zhang Ding , Paolucci Federico
Published: October 2024

We theoretically analyze the electronic transport properties of a monolayer graphene/insulator/superconductor (GIS) tunnel junction subject to a temperature gradient. For intrinsic graphene, the system shows always dissipative charge transport even in the presence of an electronic temperature difference between the two leads. Differently, the GIS produces a thermoelectric response when the graphene electrochemical potential is lifted to energies comparable to the zero-temperature gap of the superconductor, i.e., the system is particle–hole asymmetric. Indeed, the thermally biased GIS system is able to produce both a short-circuit Peltier current and an open-circuit Seebeck voltage. This thermoelectric effect is made of a linear conventional component, due to the intrinsic particle–hole asymmetry of the system, and a non-linear contribution, due to a further spontaneous particle–hole symmetry breaking. In most of the thermal and charge configurations of the GIS system, the linear component prevails. Concluding, the GIS system could be employed in the design of thermometers, electromagnetic radiation sensors, and heat engines with profound influence in superconducting quantum technologies.
Insights into the phase behavior at interfaces using vibrational sum frequency generation spectroscopy
Authors: Ghorai Anaranya , Dutta Chayan
Published: October 2024

Phase separation is ubiquitous at the interface between two distinct phases. Physical transformation during phase separation often plays a crucial role in many important mechanisms, such as lipid phase separation, which is fundamental for transport through biological membranes. Phase separation can be complex, involving changes in the physical state and the reorganization of molecular structures, influencing the behavior and function of materials and biological systems. Surface-sensitive vibrational sum frequency generation (VSFG) spectroscopy provides a powerful tool for investigating these interfacial processes. As a non-linear optical technique, VSFG spectroscopy is sensitive to changes in molecular orientation and interactions at interfaces, making it an ideal method for studying phase separation processes. Here, we review the molecular interaction mechanisms underlying phase separation. We also explore the application of VSFG spectroscopy in studying phase separation processes at different interfaces. In particular, we focus on oil–water interfaces, which are relevant in environmental and industrial contexts; polymer and lipid surfaces, important for materials science and biological membranes; and intrinsically disordered protein systems, which play key roles in cellular function and disease.
Turbulence characteristics of non-spherical isolated particles with different flatness on a rough bed surface
Authors: Zhang Rangang , Yang Shengfa , Zhang Peng
Published: October 2024

The transport of non-spherical particles on bed is significantly influenced by flow dynamics and particle shape. To study the impact of changes in the flatness of isolated bed particles on the surrounding flow characteristics, we prefabricated three isovolumetric particles with varying levels of flatness and analyzed the flow field around them using two-dimensional particle image velocimetry measurement methods. The results show that the presence of the particles significantly alters the turbulence parameters of the surrounding flow. Specifically, the influence extends up to 1D upstream of the particles, 0.5D above the particle tops, and throughout most of the downstream region, where D represents the equivalent particle diameter. The particles cause a reduction in Reynolds stress and turbulent kinetic energy in the near-bed upstream region, with a more pronounced effect observed for particles with lower flatness. Increased particle flatness is associated with a smaller difference in the longitudinal time-averaged velocity between upstream and downstream regions. In the wake region, particle flatness shows a negative correlation with Reynolds stress, longitudinal turbulence intensity, and turbulent kinetic energy, with this effect being more pronounced closer to the particles. Quadrant analysis indicates that ejection (Q2) and sweep (Q4) quadrant events remain dominant in the presence of particles, while particle flatness positively correlates with the frequency of outward (Q1) and inward (Q3) events in the wake region and negatively correlates with the frequency of Q2 and Q4 events. This study enhances our understanding of particle-fluid interactions, particularly the response relationship between non-spherical particles and turbulent mechanisms.
Enhanced electrocatalytic OER activity following electrochemical pre-cathodic treatment of Mn-substituted nickel ferrite
Authors: Singh Anchal Kishore , Kumar Naresh
Published: October 2024

In this study, the electronic engineering of a high-valent active site for enhanced oxygen evolution reaction (OER) was achieved through the electrochemical pre-cathodic treatment method (EPCTM). This method involves applying a cathodic potential to the drop-cast working electrode of Mn-substituted nickel ferrite (Ni1−xMnxFe2O4; where x = 0.0, 0.2, and 0.4) electrocatalysts. X-ray photoelectron spectroscopy analysis revealed an increase in the ratios of Ni3+/Ni2+ and Mn3+/Mn2+ in Ni1−xMnxFe2O4 after EPCTM followed by OER, leading to an enhancement in electrochemical OER current density at 600 mV overpotential by 3.65 times for x = 0.0, 5.56 times for x = 0.20, and 4.72 times for x = 0.40. This enhancement was further supported by a decrease in the slope of the anodic Tafel equation after EPCTM, indicating improved efficiency of the interaction between the working electrode and electrolyte, as a lower Tafel slope suggests better charge exchange at the electrode–electrolyte interface. The positive slope in the Mott–Schottky (MS) plot for all Ni1−xMnxFe2O4 samples confirmed the p-type nature of the electrocatalysts. Additionally, the significant decrease in the slope of the linear portion of the MS plot indicated an increase in carrier concentration after electrochemical pre-cathodic treatment in all Ni1−xMnxFe2O4 samples. This increase in p-type carrier concentration supports the observed increase in the Ni3+/Ni2+ ratio for OER after EPCTM.
Coarse-grained modeling of high-enthalpy air flows based on the updated vibrational state-to-state kinetics
Authors: Huang Yifeng , Hong Qizhen , Gu Sangdi , Wang Xiaoyong , Sun Quanhua
Published: October 2024

The state-to-state (StS) model can accurately describe high-temperature thermochemical nonequilibrium flows. For the five-species air gas mixture, we develop a comprehensive database for the state-specific rate coefficients for temperatures 300–25 000 K in this paper. The database incorporates recent molecular dynamics simulations (based on the ab initio potential energy surfaces) in the literature, and theoretical methods, including the forced harmonic oscillator model and the Marrone–Treanor model, are employed to complement the rate coefficients that are unavailable from molecular dynamics calculations. The post-shock StS simulations using the present database agree with the experimental NO infrared radiation. Based on this updated StS kinetics database, we investigate the post-shock high-enthalpy air flows by employing both the StS and coarse-grained models (CGM). The CGM, which lumps molecular vibrational states into groups, shows results that align with the StS model, even utilizing only two groups for each molecule. However, the CGM-1G model, with only one group per molecule and belonging to the multi-temperature model (but uses StS kinetics), fails to reproduce the StS results. Analysis of vibrational energy source terms for different kinetic processes and fractions of vibrational groups reveals that the deficiency of the CGM-1G model stems from the overestimation of high-lying vibrational states, leading to higher dissociation rates and increased consumption of vibrational energy in dissociation. Furthermore, the presence of the Zeldovich-exchange processes indirectly facilitates energy transfer in N2 and O2, a phenomenon not observed in binary gas systems. These findings have important implications for developing the reduced-order model based on coarse-grained treatment.
Exploring the soft pinning effect in the dynamics and the structure–dynamics correlation in multicomponent supercooled liquids
Authors: Anwar Ehtesham , Patel Palak , Sharma Mohit , Maitra Bhattacharyya Sarika
Published: October 2024

We study multicomponent liquids by increasing the mass of 15% of the particles in a binary Kob–Andersen model. We find that the heavy particles have dual effects on the lighter particles. At higher temperatures, there is a significant decoupling of the dynamics between heavier and lighter particles, with the former resembling a pinned particle to the latter. The dynamics of the lighter particles slow down due to the excluded volume around the nearly immobile heavier particles. Conversely, at lower temperatures, there is a coupling between the dynamics of the heavier and lighter particles. The heavier particles’ mass slows down the dynamics of both types of particles. This makes the soft pinning effect of the heavy particles questionable in this regime. We demonstrate that as the mass of the heavy particles increases, the coupling of the dynamics between the lighter and heavier particles weakens. Consequently, the heavier the mass of the heavy particles, the more effectively they act as soft pinning centers in both high and low-temperature regimes. A key finding is that akin to the pinned system, the self-dynamics and collective dynamics of the lighter particles decouple from each other as the mass of the heavy particles has a more pronounced impact on the latter. We analyze the structure–dynamics correlation by considering the system under the binary and modified quaternary framework, the latter describing the pinned system. Our findings indicate that whenever the heavy mass particles function as soft pinning centers, the modified quaternary framework predicts a higher correlation.
Mitigation mechanism of porous media hood for the sonic boom emitted from maglev tunnel portals
Authors: Wang Kai-Wen , Chen Guang , Wen Chih-Yung , Xiong Xiao-Hui , Liang Xi-Feng , Zhang Lei
Published: October 2024

The micro-pressure waves (MPW) released from maglev tunnel portals can generate audible sonic booms and cause structural resonance in surrounding buildings, posing challenges to developing high-speed maglev trains. This paper proposes a novel porous media hood (PMH) and investigates its mechanism for mitigating the sonic booms emitted from tunnels. The numerical model employs the improved delayed detached eddy simulation turbulence model and overset grid technology, validated against data from moving-model experiments. The influences of the PMH's inherent properties and geometric parameters on MPW, flow field evolution, and aerodynamic loads on the train body were comprehensively discussed. The research demonstrates that PMH effectively dampens the initial wavefront gradient at the entrance and reduces the MPW amplitude by intensifying radiation within its exit vicinity. The porosity of 0.2 facilitates a seamless transition for the streamlined head from the ventilated PMH to the airtight tunnel. Lengthening the PMH enhances its MPW mitigation effect, whereas the impact of PMH thickness is minor. The PMH effectively diminishes the reflection intensity of compression and expansion waves at the tunnel ends, leading to a reduction in the magnitude and changing rate of train aerodynamic loads. This underscores the PMH's potential to enhance passengers' auditory comfort and alleviate issues related to train sway.
Melting of binary mixtures
Authors: Liu Yang , Block Dietmar
Published: October 2024

The melting process of two-dimensional binary mixtures is studied using the Langevin simulation method. The melting point of each component in a binary mixture is determined by the local relative interparticle distance fluctuation method. The results show that, compared with the monodisperse system, the components of the binary mixture exhibit a multi-step melting characteristic. Further, the melting process of binary mixtures is found to depend on the mixing ratio and charge ratio. It is shown that particle hopping motion plays a key role in understanding melting in binary mixtures.
Macrotransport of active particles in periodic channels and fields: Rectification and dispersion
Authors: Peng Zhiwei
Published: October 2024

Transport and dispersion of active particles in structured environments, such as corrugated channels and porous media, are important for the understanding of both natural and engineered active systems. Owing to their continuous self-propulsion, active particles exhibit rectified transport under spatially asymmetric confinement. While progress has been made in experiments and particle-based simulations, a theoretical understanding of the effective long-time transport dynamics in spatially periodic geometries remains less developed. In this paper, we apply generalized Taylor dispersion theory to analyze the long-time effective transport dynamics of active Brownian particles (ABPs) in periodic channels and fields. We show that the long-time transport behavior is governed by an effective advection–diffusion equation. The derived macrotransport equations allow us to characterize the average drift and effective dispersion coefficient. For the case of ABPs subject to a no-flux boundary condition at the channel wall, we show that regardless of activity, the average drift is given by the net diffusive flux along the channel. For ABPs, their activity is the driving mechanism that sustains a density gradient, which ultimately leads to rectified motion along the channel. Our continuum theory is validated against direct Brownian dynamics simulations of the Langevin equations governing the motion of each ABP.
Early time wetting kinetics in surface-directed spinodal decomposition for off-critical quenches: A molecular dynamics study
Authors: Zaidi Syed Shuja Hasan , Suvarna Saumya , Priya Madhu , Puri Sanjay , Jaiswal Prabhat K.
Published: October 2024

We present results from the molecular dynamics simulation of surface-directed spinodal decomposition in binary fluid mixtures (A + B) with off-critical compositions. The aim is to elucidate the role of composition ratio in the early time wetting kinetics under the influence of long-range surface potential. In our simulations, the attractive part of surface potential varies as V(z) = −ϵa/zn, with ϵa being the surface-potential strength. The surface prefers the “A” species to form the wetting layer. Its thickness [R1(t)] for the majority wetting (number of A-type particles [NA] > number of B-type particles [NB]) grows as a power-law with an exponent of 1/(n + 2). This is consistent with the early time kinetics in the form of potential-dependent growth present in the Puri–Binder model. However, for minority wetting (NA < NB), the growth exponent in R1(t) is less than 1/(n + 2). Furthermore, on decreasing the field strength ϵa, we recover 1/(n + 2) for a minority wetting case. We provide phenomenological arguments to explain the early time wetting kinetics for both cases.
Probing ferroelectric phase transitions in barium titanate single crystals via in situ second harmonic generation microscopy
Authors: Kirbus Benjamin , Seddon Samuel D. , Kiseleva Iuliia , Beyreuther Elke , Rüsing Michael , Eng Lukas M.
Published: October 2024

Ferroelectric materials play a crucial role in a broad range of technologies due to their unique properties that are deeply connected to the pattern and behavior of their ferroelectric (FE) domains. Chief among them, barium titanate (BaTiO3; BTO) sees widespread applications such as in electronics but equally is a ferroelectric model system for fundamental research, e.g., to study the interplay of such FE domains, the domain walls (DWs), and their macroscopic properties, owed to BTO’s multiple and experimentally accessible phase transitions. Here, we employ Second Harmonic Generation Microscopy (SHGM) to in situ investigate the cubic-to-tetragonal (at ∼126°C) and the tetragonal-to-orthorhombic (at ∼5°C) phase transition in single-crystalline BTO via three-dimensional (3D) DW mapping. We demonstrate that SHGM imaging provides the direct visualization of FE domain switching as well as the domain dynamics in 3D, shedding light on the interplay of the domain structure and phase transition. These results allow us to extract the different transition temperatures locally, to unveil the hysteresis behavior, and to determine the type of phase transition at play (first/second order) from the recorded SHGM data. The capabilities of SHGM in uncovering these crucial phenomena can easily be applied to other ferroelectrics to provide new possibilities for in situ engineering of advanced ferroic devices.
Folds from fold: Exploring topological isoforms of a single-domain protein
Authors: Qu Zhiyu , Xu Lianjie , Jiang Fengyi , Liu Yuan , Zhang Wen-Bin
Published: October 2024

Expanding the protein fold space beyond linear chains is of fundamental significance, yet remains largely unexplored. Herein, we report the creation of seven topological isoforms (i.e., linear, cyclic, knot, lasso, pseudorotaxane, and catenane) from a single protein fold precursor by rewiring the connectivity of secondary structure elements of the SpyTag-SpyCatcher complex and mutating the reactive residue on SpyTag to abolish the isopeptide bonding. These topological isoforms can be directly expressed in cells. Their topologies were confirmed by combined techniques of proteolytic digestion, fluorescence correlation spectroscopy (FCS), size-exclusion chromatography (SEC), and topological transformation. To study the effects of topology on their structures and properties, their biophysical properties were characterized by differential scanning calorimetry (DSC), heteronuclear single quantum coherence nuclear magnetic resonance spectroscopy (HSQC-NMR), and circular dichroism (CD) spectroscopy. Molecular dynamics (MD) simulations were further performed to reveal the atomic details of structural changes upon unfolding. Both experimental and simulation results suggest that they share a similar, well-folded hydrophobic core but exhibit distinct folding/unfolding dynamic behaviors. These results shed light onto the folding landscape of topological isoforms derived from the same protein fold. As a model system, this work improves our understanding of protein structure and dynamics beyond linear chains and suggests that protein folds are highly amenable to topological variation.
Uniting education, research, healthcare, and society to advance women’s heart health
Authors: Schakelaar Michael Y. , Maas Annemieke , van Ommen Anne-Mar L.N. , Spiering Anna E. , de Jonge Roos , Wijchers Patrick , van Rossum Gerda , Heesters Balthasar A. , de Jong Olivier G. , Zandveld Jelle , Rebel Heggert G. , Meeldijk Jan , Pijnappel Emma W. , van Dijk Suzanne , Di Maggio Alessia , Nijssen Olaf , Sanders Jorine G.F. , Hoogerwerf Lies , van Spaandonk Mike , Crnko Sandra , Koorman Thijs , Jenniskens Kevin , Onland-Moret N. Charlotte , van Geelen Stefan M. , ten Broeke Toine , van Royen-Kerkhof Annet , Dilaver Gönül , Oliveira Sabrina , Kok Robbert J. , van Laake Linda W. , van der Harst Pim , Spiering Wilko , Rutten Frans H. , van Brussel Marco , den Ruijter Hester M. , Bovenschen Niels
Published: October 2024

Complex health challenges require professionals to operate across disciplines and to better connect with society. Here, we showcase a community-engaged and challenge-based educational model in which undergraduate students conduct transdisciplinary research on authentic complex biomedical problems. This concept reinforces translational medicine, human capital, and exemplifies synergy between education, research, healthcare, and society.
The universal thermodynamic properties of extremely compact objects
Authors: Mathur Samir D , Mehta Madhur
Published: October 2024

An extremely compact object (ECO) is defined as a quantum object without horizon, whose radius is just a small distancesoutside its Schwarzschild radius. We show that any ECO of massMind + 1 dimensions withs≪(M/mp)2/(d−2)(d+1)lpmust have (at leading order) the same thermodynamic properties—temperature, entropy and radiation rates—as the corresponding semiclassical black hole of massM. An essential aspect of the argument involves showing that the Tolman–Oppenheimer–Volkoff equation has no consistent solution in the region just outside the ECO surface, unless this region is filled with radiation at the (appropriately blueshifted) Hawking temperature. In string theory it has been found that black hole microstates are fuzzballs—objects with no horizon—which are expected to have a radius that is only a little larger than the horizon radius. Thus the arguments of this paper provide a nice closure to the fuzzball paradigm: the absence of a horizon removes the information paradox, and the thermodynamic properties of the semiclassical hole are nonetheless recovered to an excellent approximation.
LES-YOLO: efficient object detection algorithm used on UAV for traffic monitoring
Authors: Zhang Hongyu , Deng Lixia , Lin Shoujun , Zhang Honglu , Dong Jinshun , Wan Dapeng , Bi Lingyun , Liu Haiying
Published: October 2024

The use of UAVs for traffic monitoring greatly facilitates people’s lives. Classical object detection algorithms struggle to balance high speed and accuracy when processing UAV images on edge devices. To solve the problem, the paper introduces an efficient and slim YOLO with low computational overhead, named LES-YOLO. In order to enrich the feature representation of small and medium objects in UAV images, a redesigned backbone is introduced. And C2f combined with Coordinate Attention is used to focus on key features. In order to enrich cross-scale information and reduce feature loss during network transmission, a novel structure called EMS-PAN (Enhanced Multi-Scale PAN) is designed. At the same time, to alleviate the problem of class imbalance, Focal EIoU is used to optimize network loss calculation instead of CIoU. To minimize redundancy and ensure a slim architecture, the P5 layer has been eliminated from the model. And verification experiments show that LES-YOLO without P5 is more efficient and slimmer. LES-YOLO is trained and tested on the VisDrone2019 dataset. Compared with YOLOv8n-p2, mAP@0.5 and Recall has increased by 7.4% and 7%. The number of parameters is reduced by over 50%, from 2.9 M to 1.4 M, but there is a certain degree of increase in FLOPS, reaching 18.8 GFLOPS. However, the overall computational overhead is still small enough. Moreover, compared with YOLOv8s-p2, both the number of parameters and FLOPS are significantly reduced
, while the performance is similar
. As for real-time, LES-YOLO reaches 138 fps on GPU and a maximum of 78 fps on edge devices of UAV.
Simulation case study of precise orbit determination for IGSO satellites using onboard Ka/GNSS observations
Authors: Jiang Kecai , Mu Renhai , Li Min , Li Wenwen , Wang Yubin , Xie Xin , Chang Chuntao , Yang Jie , Zhao Qile
Published: October 2024

Inter-satellite links (ISLs) can provide a more accurate spatial reference for inclined geosynchronous orbit satellite (IGSO) satellites than onboard global navigation satellite system (GNSS) side-lobe signals. In this study, precise orbit determination (POD) quality is analyzed based on onboard Ka/GNSS observations using a simulated IGSO satellite orbit. Considering the similar orbit altitude, we first select three IGSO satellites from BeiDou Navigation Satellite System (BDS-3) as target satellites, which have real Ka-band measurements available, along with other BDS-3 satellites and ground anchor stations, enabling us to evaluate POD performance. For the POD results using real Ka-band measurements, the root mean square of the residuals can reach 10.9 cm, and the orbit consistency in the 3D direction is better than 0.35 m. Additionally, simulations are conducted for onboard GNSS, ISL, and ground anchor-satellite link (GSL), considering the different constraints on the Ka-band resources. When only GNSS measurements are used, the 3D orbit accuracy estimated by the simulated theoretical orbit is approximately 1.5 m, and when only ISL measurements are used, the 3D orbit accuracy can reach approximately 0.35 m. However, when additional ISL and GSL measurements are included, the POD accuracy can exceed 0.28 m. These results demonstrate that incorporating Ka-band measurements can effectively enhance the POD accuracy for high-orbit satellites.
Shock-induced twinning/detwinning and spall failure in Cu–Ta nanolaminates at atomic scales
Authors: Echeverria M J , Fensin S J , Dongare A M
Published: October 2024

This study provides new insights into the role of interfaces on the deformation and failure mechanisms in shock-loaded Cu–Ta–Cu trilayer system. The thickness of the Ta layer, piston velocities, and shock pulse durations were varied to explore the impact of impedance mismatch and loading conditions on spallation behavior and twin formation. It was found that the interfaces play a crucial role in the dynamic response of these multilayered systems since secondary reflection waves generated at the interfaces significantly affected the peak stress and pressure profiles, influencing void nucleation and failure modes. In the trilayer systems, failure predominantly occurred at interfaces and within the Ta layer, with void nucleation sites and twinning behavior being markedly different compared to single-crystal Cu and Ta. Increasing the Ta layer thickness modified the wave interactions, leading to different failure locations. Higher piston velocities were associated with increased spall strength by enhancing wave interactions and void formation, particularly at the interfaces and within the Ta layer, under specific configurations. Additionally, shorter shock pulse durations facilitated earlier initiation of the release fan, reducing twin formation and altering the failure dynamics by accelerating twin annihilation and pressure release.
Fabrication of a uniform quantum dot film with a high quantum yield
Authors: Oh Min Woo , Son Byung Hee , Yoon Jee Sang , Yoo Yonghwan , Kim Yongduk , Choi Soo Bong , Ahn Yeong Hwan , Cho Won Bae , Park Doo Jae
Published: October 2024

We present a method that uses viscosity-lowering materials to fabricate flexible polydimethylsiloxane-based quantum dot (QD) films with high quantum yield (QY) and improved uniformity. We found that the aggregation of individual QDs was prevented, and the QY improved simultaneously in films that contained surfactants. These films showed an improved absorption of approximately 27% in the near-UV and blue light regions, along with an improved photoluminescence of approximately 18%, indicating improved light conversion from the UV to the visible frequency region.
A study of the coupled dynamics of asymmetric absorbing clusters in a photophoretic trap
Authors: Pahi Anita , Paul Shuvojit , Banerjee Ayan
Published: October 2024

We report a study on the dynamics of absorbing asymmetric carbon clusters trapped by a loosely focused Gaussian beam using photophoretic force. At high laser powers, all the trapped clusters display rotation coupled with oscillation along the axial direction, with a majority spinning about a body fixed axis, while the rest display dual spin as well as orbital motion about a fixed point in space. The spinning and orbiting frequency is inversely proportional to the amplitude of the axial oscillation–with one growing at the expense of the other. Further, the frequencies of these rotations are not proportional to the laser power, but to the trap stiffnesses inferred from the corresponding natural frequencies. The clusters also stop rotating below a certain laser power, and execute random thermal fluctuations. Our work suggests that the dynamics of clusters trapped with photophoretic force are largely dependent on the cluster size and morphology, which could, in principle, be tuned to obtain various motional responses, and help in the design of rotating micromachines in air.