bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanically robust ultrathin nanofibrous films by using microfluidic-based continuous printing
Authors: Chen Xiao , Su Jiaqing , Cheng Sha , Huang Cheng , Zhao Chunxia , Teng Chao , Zhang Pengchao
Published: August 2024

Free-standing mechanically robust ultrathin nanofibrous films have been fabricated by using microfluidic-based continuous printing owing to the symmetric solvent exchange, showing great potential for practical applications.
A lignin-derived carbon dot-upgraded bacterial cellulose membrane as an all-in-one interfacial evaporator for solar-driven water purification
Authors: Mate Nirmiti , Nabeela Kallayi , Preethikumar Gopika , Pillai Saju , Mobin Shaikh M.
Published: August 2024

Solar-driven interfacial evaporation as an efficient approach for wastewater treatment and seawater desalination.
Tailoring the electrode material and structure of rocking-chair capacitive deionization for high-performance desalination
Authors: Wang Hao , Liu Yong , Li Yuquan , Xu Xingtao , Lu Ting , Pan Likun
Published: August 2024

Rocking-chair capacitive deionization (RCDI) is a rising star in the CDI field, delivering ultrahigh desalination efficiency and excellent cycling stability.
Electrocatalytic oxygen evolution activity of nickel-doped manganese oxide nanorods in acid
Authors: Xin Bowen , Li Yvpei , Wang Dong , Xing Peize , Wang Chao
Published: August 2024

Nickel-doped manganese oxide nanorods are synthesized and exhibit moderate stability towards oxygen evolution reaction in acid.
Combinatorial synthesis of substituted pyrazolo-fused quinazolines by the Rh(iii)-catalyzed [5 + 1] annulation of phenyl-1H-pyrazol-5-amine with alkynoates and alkynamides
Authors: Chiu Wei-Jung , Chu Ting-Yen , Sun Chung-Ming
Published: August 2024

A Rh(iii)-catalyzed C–H activation/cyclization cascade is developed for the first divergent synthesis of pyrazolo[1,5-a]quinazolines through a [5 + 1] annulation reaction exclusively.
Direct hydrogenation of natural oils to fatty alcohols enabled by an alcoholysis/hydrogenation relay strategy and two-phase solvent system
Authors: Chen Ying , Zhou Min-Jie , Hu Yue , Xie Yinjun
Published: August 2024

A relay strategy consisting of alcoholysis and hydrogenation was developed for the direct homogeneous hydrogenation of various natural oils to fatty alcohols. The challenge of catalyst poisoning was resolved by the use of a two-phase solvent system.
TFPN-mediated racemization/epimerization-free amide and peptide bond formation
Authors: Yang Jinhua , Zhang Dou , Chang Yajing , Zhang Bo , Shen Peng , Han Chunyu , Zhao Junfeng
Published: August 2024

A new electron-deficient aromatic-based coupling reagent, tetrafluorophthalonitrile (TFPN), designed according to the concept of dual coupling reagents, is developed to facilitate amide and peptide bond formation in a one-pot, two-step manner.
2H-SnS2 assembled with petaloid 1T@2H-MoS2 nanosheet heterostructures for room temperature NO2 gas sensing
Authors: Hambir Shraddha , Shinde Shashikant , Pathan H. M. , Kaushik Som Datta , Rout Chandra Sekhar , Jagtap Shweta
Published: August 2024

In this study, we explored the gas-sensing capabilities of MoS2 petaloid nanosheets in the metallic 1T phase with the commonly investigated semiconducting 2H phase.
The effects of droplet stabilization by surfactants and nanoparticles on leakage, cross-talk, droplet stability, and cell adhesion
Authors: Waeterschoot Jorik , Kayahan Emine , Breukers Jolien , Lammertyn Jeroen , Casadevall i Solvas Xavier
Published: August 2024

Two popular fluorosurfactants RAN (A) and Krytox (B) were compared with partially fluorinated nanoparticles (C) for their use in droplet microfluidics.
Rethinking nuclear shaping: insights from the nuclear drop model
Authors: Dickinson Richard B. , Abolghasemzade Samere , Lele Tanmay P.
Published: August 2024

The resistance of the liquid drop-like nucleus to deformation is dependent on whether the nuclear lamina is smooth or wrinkled. When it is smooth and taut, the nuclear shape can be calculated from geometric constraints on volume and surface area.
A 3D-printed fully biocompatible supercapacitor
Authors: Mevada Chirag , Tissari Jonne , Parihar Vijay Singh , Tewari Amit , Keskinen Jari , Kellomäki Minna , Mäntysalo Matti
Published: August 2024

A fully biocompatible supercapacitor was fabricated utilizing a dopamine-grafted activated carbon-based (DPBAC) electrode material along with a choline chloride–urea-based eco-friendly Reline deep eutectic solvent electrolyte.
Single atom Cu anchored graphitic-C3N5 for photocatalytic selective oxidation of biomass-derived furfurals to maleic anhydride
Authors: Li Kaihua , Zhou Weihao , Cao Xincheng , Xu Xuran , Lin Yamei , Wang Kui , Jiang Jianchun , Lu Guo-Ping
Published: August 2024

A copper single-atom catalyst (Cu1@C3N5-1) has been developed for photocatalytic oxidation of biomass-derived furfural and 5-hydroxymethylfurfural to obtain maleic anhydride. 1O2 and ·O2− play a synergetic oxidation role during the reaction.
Flexible near-infrared organic photodetectors based on a high work function anode
Authors: Ma Jun , Wang Jiahui , Hu Junli , Liu Yichun
Published: August 2024

Flexible near-infrared organic photodetectors with an optimized PEDOT:PSS anode present more sensitive detectivity than the control flexible device with the traditional ITO anode and achieve heart rate and blood oxygen saturation monitoring.
Analysis and improvement of the reactive power cascade control strategy for MMC‐HVDC receiving‐end converter connected to weak grid
Authors: Xu Junhua , He Guopeng , Liu Yong , Tang Songqin , Xie Daiyu , Chen Mingyuan
Published: August 2024

The weak AC grid in a modular multilevel converter modular multilevel converter based high voltage direct current (MMC‐HVDC) receiving‐end system requires faster reactive power support from the receiving‐end MMC. However, under the MMC traditional constant AC voltage dual‐loop control strategy, the increase in MMC's reactive power support speed will reduce the system stability. The reactive power cascade control strategy is a novel MMC control strategy. The analysis in this paper demonstrates that it possesses advanced performance under faster reactive power support, which is required by the MMC connected to a weak AC grid, but, some of its control links and operations can cause impacts exceeding that a weak AC grid can undertake. To solve this problem, based on the original control strategy, this paper proposes an improved reactive power cascade control strategy for weak AC grid conditions. The complete framework and the detailed design of primary control links of the improved cascade control strategy are displayed in this paper. Finally, a digital simulation has been conducted to validate the analysis and the proposed improved control strategy in this paper.
Comparison of corona effect prediction criteria on sphere‐plane configuration
Authors: De La Hoz Manuel , Pieterse Petrus Jacobus , Etxegarai Agurtzane , Gonzalez Diego , Mazon Ángel Javier , Uhrlandt Dirk
Published: August 2024

When designing high‐voltage elements, knowing if the corona effect will be present during their life cycle is relevant. Therefore, designers consider several prediction criteria based on physical features related to breakdown discharge principles to predict the corona effect. The introduced practical set‐up consists of a concave cone electrode with a hemispheric tip above a plate to evaluate selected corona prediction criteria. The hemisphere has a fixed diameter of 7 mm, and the electrode separation ranges from 2.5 to 39 cm. Information about the corona mode inception under different voltage sources was extracted using an intensified charge‐coupled device camera and a partial discharge metre. The prediction criteria were connected to a specific corona mode depending on the main discharge structure behind its development. The average deviation between these criteria and experimental results was around eight percent. Underlying assumptions in criteria are also discussed in light of the experimental results.
Low angle estimation in MIMO radar based on unitary ESPRIT under spatial smoothing
Authors: Qin Cong , Zhang Qin , Zheng Guimei , Zheng Yu , Zhang Gangsheng
Published: August 2024

Aiming at the problem that the overlapping of multipath signals seriously affects the radar's performance of the elevation angle estimation for low‐altitude targets, the authors combine the unitary ESPRIT (UESPRIT) and the multi‐input and multi‐output (MIMO) radar system and propose an algorithm based on UESPRIT to estimate the direction of arrival for low‐altitude targets. Firstly, the virtual matrix after generalised matched filtering of MIMO radar multipath received signals is vectorised. Secondly, for the coherence of direct and reflected wave signals, which cannot be directly processed by the UESPRIT algorithm, the signal preprocessing is performed by spatial smoothing of the sampled data matrices. Finally, the low‐altitude target estimation is carried out by using the UESPRIT algorithm. The Cramer–Rao bound (CRB) for arbitrary unbiased estimation of angle estimation is derived. The relationship between the estimation performance of the algorithm and the signal‐to‐noise ratio, the number of snapshots and the number of elements is analysed by simulation and compared with CRB. The simulation results show that the algorithm can still effectively estimate the elevation angle of low‐altitude targets under the mutual weakening of direct and multipath reflection signals, and has better performance for low‐altitude targets than generalised MUSIC.
Short‐term load forecasting facilitated by edge data centres: A coordinated edge‐cloud approach
Authors: Li Junlong , Fang Lurui , Wei Xiangyu , Fang Mengqiu , Xiang Yue , You Peipei , Zhang Chao , Gu Chenghong
Published: August 2024

Compared to load forecasting at the national level, two challenges arise in providing accurate forecasting for LV and MV networks: (1) customers within LV and MV networks are much less, implying greater volatility within those load profiles; (2) not all customers have smart metres. Particularly, the two challenges would exacerbate forecasting performance under unexpected events, such as extreme weather and COVID‐19 outbreaks. To secure accurate short‐term load forecasting for LV and MV networks, this paper customised a Spatio‐Temporal Edge‐Cloud‐coordinated (STEC) approach on a loop training structure—LV networks to MV networks to LV networks. For each LV network, this approach utilises XGboost to learn the relationship between weather data, substation‐side loads, and a few accessible customer‐side load data to deliver rough forecasting. Then, it adopts the rough forecasting results and accessible data for all LV networks within an MV network to train the convolutional neural networks and gated recurrent unit (CNN‐GRU) network. This step provides load forecasting for MV networks and simultaneously refines load forecasting for LV networks by generating the interacting relationship between LV substations of different locations. Case studies reveal that the STEC approach successfully extrapolates the demand‐varying information from long‐term datasets and improves short‐term forecasting performance under both normal scenarios and newly occurring unexpected scenarios for LV and MV networks. The loop training structure halves the forecasting error, compared to classic methodology by utilising the local data only for MV networks.
Application of the Eddington inversion method to constrain the dark matter halo of galaxies using only observed surface brightness profiles
Authors: Sánchez Almeida Jorge , Plastino Angel R. , Trujillo Ignacio
Published: August 2024

Context. The halos of low-mass galaxies may allow us to constrain the nature of dark matter (DM), but the kinematic measurements needed to diagnose the required properties are technically extremely challenging. However, the photometry of these systems is doable.

Aims. Using only stellar photometry, we wanted to constrain key properties of the DM halos in low-mass galaxies.

Methods. Unphysical pairs of DM gravitational potentials and starlight distributions can be identified if the pair requires a distribution function, f, that is negative somewhere in the phase space. We used the classical Eddington inversion method (EIM) to compute f for a battery of DM gravitational potentials and ∼100 observed low-mass galaxies with M⋆ between 106 and 108 M⊙. The battery includes Navarro, Frenk, and White (NFW) potentials (expected from cold DM) and potentials stemming from cored mass distributions (expected in many alternatives to cold DM). The method assumes spherical symmetry and an isotropic velocity distribution and requires fitting the observed profiles with analytic functions, for which we used polytropes (with zero inner slope, also known as core) and profiles with variable inner and outer slopes. The validity of all these assumptions is analyzed.

Results. In general, the polytropes fit the observed starlight profiles well. If they are the correct fits (which could be the case), then all galaxies are inconsistent with NFW-like potentials. Alternatively, when the inner slope is allowed to vary for fitting, between 40% and 70% of the galaxies are consistent with cores in the stellar mass distribution and thus inconsistent with NFW-like potentials.

Conclusions. Even though the stellar mass of the observed galaxies is still not low enough to constrain the nature of DM, this work shows the practical feasibility of using the EIM technique to infer DM properties only from photometry.
X-Shooting ULLYSES: Massive stars at low metallicity
Authors: Sander A. A. C. , Bouret J.-C. , Bernini-Peron M. , Puls J. , Backs F. , Berlanas S. R. , Bestenlehner J. M. , Brands S. A. , Herrero A. , Martins F. , Maryeva O. , Pauli D. , Ramachandran V. , Crowther P. A. , Gómez-González V. M. A. , Gormaz-Matamala A. C. , Hamann W.-R. , Hillier D. J. , Kuiper R. , Larkin C. J. K. , Lefever R. R. , Mehner A. , Najarro F. , Oskinova L. M. , Schösser E. C. , Shenar T. , Todt H. , ud-Doula A. , Vink J. S.
Published: August 2024

Context.The spectral analysis of hot, massive stars is a fundamental astrophysical method of determining their intrinsic properties and feedback. With their inherent, radiation-driven winds, the quantitative spectroscopy for hot, massive stars requires detailed numerical modeling of the atmosphere and an iterative treatment in order to obtain the best solution within a given framework.

Aims.We present an overview of different techniques for the quantitative spectroscopy of hot stars employed within the X-Shooting ULLYSES collaboration, ranging from grid-based approaches to tailored spectral fits. By performing a blind test for selected targets, we gain an overview of the similarities and differences between the resulting stellar and wind parameters. Our study is not a systematic benchmark between different codes or methods; our aim is to provide an overview of the parameter spread caused by different approaches.

Methods.For three different stars from the XShooting ULLYSES sample (SMC O5 star AzV 377, LMC O7 star Sk -69° 50, and LMC O9 star Sk-66° 171), we employ different stellar atmosphere codes (CMFGEN,Fastwind, PoWR) and different strategies to determine their best-fitting model solutions. For our analyses, UV and optical spectroscopy are used to derive the stellar and wind properties with some methods relying purely on optical data for comparison. To determine the overall spectral energy distribution, we further employ additional photometry from the literature.

Results.The effective temperatures found for each of the three different sample stars agree within 3 kK, while the differences in loggcan be up to 0.2 dex. Luminosity differences of up to 0.1 dex result from different reddening assumptions, which seem to be systematically larger for the methods employing a genetic algorithm. All sample stars are found to be enriched in nitrogen. The terminal wind velocities are surprisingly similar and do not strictly follow theu∞−Teffrelation.

Conclusions.We find reasonable agreement in terms of the derived stellar and wind parameters between the different methods. Tailored fitting methods tend to be able to minimize or avoid discrepancies obtained with coarser or increasingly automatized treatments. The inclusion of UV spectral data is essential for the determination of realistic wind parameters. For one target (Sk -69° 50), we find clear indications of an evolved status.
Different behaviour of the gas-phase and stellar metallicity in the central part of MaNGA galaxies
Authors: Zinchenko I. A. , Vílchez J. M.
Published: August 2024

We quantified the disparity between gas-phase and stellar metallicity in a large galaxy sample obtained from the MaNGA DR17 survey. We found that the gas metallicity is on average closely aligned with the stellar metallicity in the centers of intermediate-mass galaxies. Conversely, the difference is notably larger within the center of massive galaxies. It reaches about −0.18 dex on average for the most massive galaxies, while for low-mass galaxies, the gas metallicity exhibits a slightly lower value than the stellar metallicity. Moreover, the most prominent instances of a reduced gas-phase metallicity in relation to stellar metallicity were observed within the centers of massive red galaxies with low specific star formation rates. Because of the absence of a correlation between the integral mass fraction of neutral gas and the disparity between gas and stellar metallicity, we suggest that the diminished gas-phase metallicity in the centers of massive galaxies might be attributed to the replenishment of gas-depleted central regions through processes such as radial gas flows or accretion from the circumgalactic medium rather than gas infall from the intergalactic medium.
Relation between the geometric shape and rotation of Galactic globular clusters
Authors: Cruz Reyes Mauricio , Anderson Richard I.
Published: August 2024

We homogeneously measured the elliptical shapes of 163 globular clusters (GCs) using the on-sky distribution of their cluster members and the third data release of the ESA mission Gaia (DR3). The astrometry enables the differentiation of stars within clusters from those in the field. This feature is particularly valuable for clusters located in densely populated areas of the sky, where conventional methods for measuring the geometry of the GCs are not applicable. The median axial ratio of our full sample is 〈b/a〉 = 0.935−0.090+0.033 and 0.986−0.004+0.009 for the subset of 11 GCs previously studied based on Hubble Space Telescope imaging. We investigated whether the minor axis of the ellipses can be interpreted as a pseudo-rotation axis by comparing it to measurements of cluster rotation. Using the radial velocities from Gaia, we detected rotation for three clusters, NGC 5139, NGC 104, and NGC 6341, and observed an alignment between the pseudo-rotation axis and the 2D projection of the real rotation axis. To expand the set of clusters for which rotation has been detected, we analyzed multiple literature references. Depending on the reference used for comparison, we observed an alignment in between 76% to 100% of the clusters. The lack of an alignment observed in some clusters may be linked to different scales analyzed in various studies. Several studies have demonstrated that the orientation of rotation varies with the distance from the center. We estimate that the next Gaia release will increase the number of stars with radial velocities in GCs from ~10 000 in Gaia DR3 to ~55 000 in Gaia DR4. This will enable the measurement of rotation and ellipticities at identical angular scales for additional clusters, which will help us to clarify whether the previously mentioned alignment occurs in all clusters.
Data – driven neuronal dynamics: Model identification and spiking analysis
Authors: Mao Yicheng , Liu Xianbin
Published: August 2024

Neurons serve as the fundamental unit in the structure and functionality of the nervous system, and the large cluster network formed by their interconnection determines the perception, learning, emotion, memory and other behaviors of the organism. While prior studies of neurons primarily focused on costly experiments and feature-based modeling, recent advancements in computing power and algorithms have made it possible to identify and analyze system with data-driven approaches. This study introduces a data-driven method for the identification of neuronal systems, and the result shows that the method is of great precision for further study. In addition, in order to investigate the mechanisms underlying the transition between resting and active states, a finite difference scheme is developed to calculate the mean first exit time and spiking frequency of neuronal systems. Notably, we propose the concept of noise coupling effect in our study, which elaborates that the spiking of a neuronal dynamical system can occur more rapidly under less stringent conditions when driven by the potential fluctuation of both Gaussian white noise and Lévy noise.
Non-decreasing martingale couplings
Authors: Jourdain Benjamin , Shao Kexin
Published: August 2024

For many examples of couples (μ, ν) of probability measures on the real line in the convex order, we observe numerically that the Hobson and Neuberger martingale coupling, which maximizes for ρ = 1 the integral of |y − x|ρ with respect to any martingale coupling between μ and ν, is still very close to maximize this integral for ρ ∈ (0, 2) and minimize it for ρ > 2. We investigate theoretically when it is an optimizer for ρ ≠ 1 and exhibit rather restrictive sufficient conditions. We also exhibit couples (μ, ν) such that it is not an optimizer. The support of the Hobson and Neuberger coupling is known to satisfy some monotonicity property which we call non-decreasing. We check that the non-decreasing property is preserved for maximizers when ρ ∈ (0, 1]. In general, there exist distinct non-decreasing martingale couplings, and we find some decomposition of ν which is in one-to-one correspondence with martingale couplings non-decreasing in a generalized sense.
Surgical Management of Ipsilateral Internal Carotid Artery Stenosis and Unruptured Intracranial Aneurysm: Case Review and Treatment Considerations
Authors: Gautam Diwas , Findlay Matthew C. , Cole Kyril L. , Couldwell William T. , Rennert Robert C.
Published: August 2024

Introduction The coexistence of carotid artery stenosis and a concomitant downstream ipsilateral unruptured intracranial aneurysm requires unique treatment considerations to balance the risk of thromboembolic complications from carotid artery stenosis and the risk of subarachnoid hemorrhage from intracranial aneurysm rupture. These considerations include the selection of optimal treatment modalities, the order and timing of interventions, and potential management of antiplatelet agents with endovascular approaches. We present strategies to optimize treatment in such a case.

Case Report We discuss the case of a 69-year-old woman with 90% stenosis of the right internal carotid artery and an ipsilateral, wide-necked, 4.8-mm, irregular-appearing right A1–2 junction aneurysm with an associated daughter sac. Open, endovascular, and mixed treatment strategies were considered. The patient selected and underwent a staged, open treatment approach with a carotid endarterectomy followed by a right craniotomy for microsurgical clipping of the aneurysm 5 days later. Both procedures were performed on daily full-dose aspirin without complications. On follow-up, the right carotid artery was widely patent, the aneurysm was secured, and the patient remained at her neurologic baseline.

Discussion The presented strategy for ipsilateral carotid artery stenosis and an unruptured intracranial aneurysm initially optimized cerebral perfusion to mitigate ischemic risks while permitting timely aneurysm intervention without a need for dual antiplatelet therapy or to traverse an earlier procedure site.
Reaction under Ball-Milling: Solvent- and Metal-Free One-Pot Diastereoselective Synthesis of Tetrahydroquinoline Derivatives as Potential Antibacterial and Anticancer Agents
Authors: Adak Laksmikanta , Roy Keya , Saha Anay , Sahoo Suprakash , Banerjee Subhrajyoti , Mukhopadhyay Chitrangada Das , Banerjee Subhash
Published: August 2024

A mild and efficient one-pot, three-component ball-mill-assisted reaction of aldehydes, anilines, and dihydrofuran (or dihydropyran and cyclohexenone) has been described for the first time in the presence of the catalytic amount of aqueous perchloric acid (8 mol%) at room temperature under organic solvent- and metal-free conditions. The reactions are fast (1 h), providing the products with excellent yields and high diastereoselectivity. This procedure endows a simple, efficient, and cost-effective method for the diastereoselective synthesis of furano- and pyrano-tetrahydroquinolines and phenanthridinone derivatives, which are important biological compounds. The diastereomers with cis configuration were isolated as major products. The H–H COSY, NOESY experiments and X-ray crystallographic analysis of selected compounds were performed to confirm the cis isomer. The synthesized tetrahydroquinolines have been evaluated in vitro for their antibacterial and anticancer activities, and it was found that both the prepared compounds showed significant antibacterial and anticancer properties.
Solvent-Controlled Divergent Synthesis of Thiocyanated Carbazoles and Di/Triphenylamines
Authors: Tang You-Hui , Chen Peng , Jiang Yi-Jun , Yin Jin , Shi Jianghuan
Published: August 2024

A solvent-controlled divergent thiocyanation of carbazoles and di/triphenylamines has been developed. Using either CH3CN/H2O (3:1) or DMSO as the solvent, a facile and efficient protocol for the solvent-controlled divergent synthesis of mono- and di-thiocyanation of carbazoles and di/triphenylamines was achieved. The salient features of this transformation include simple and mild reaction conditions, easily available substrates, and broad substrate scope.
Comparison of Full-Field Digital Mammography with Synthesized Mammography from Tomosynthesis in a Diagnostic population: Prospective Study
Authors: Dhamija Ekta , Mohan Supraja Laguduva , Anand Roshni , Khan Maroof Ahmad , Deo Sankaravamsam Venkata Suryanarayana , Hari Smriti
Published: August 2024

Background Synthesized mammography (SM) refers to two-dimensional (2D) images derived from the digital breast tomosynthesis (DBT) data. It can reduce the radiation dose and scan duration when compared with conventional full-field digital mammography (FFDM) plus tomosynthesis.

Purpose To compare the diagnostic performance of 2D FFDM with synthetic mammograms obtained from DBT in a diagnostic population.

Materials and Methods A total of 1,468 mammograms with both FFDM and SM + DBT images were obtained and analyzed over 2 years, after obtaining approval from the institute ethics committee. The images were reported and compared as per the 2013 American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) lexicon in terms of breast density, morphological features of mass, calcifications, and presence of asymmetry or architectural distortion followed by the BI-RADS category. The agreement between the two modalities was studied using the Kappa value, and the radiation exposure dose was recorded in both groups.

Results FFDM and SM + DBT showed strong agreement for breast density, mass characteristics, and detection of calcifications (kappa > 0.8). Downstaging of breast density and mass density were seen by SM + DBT without any statistically significant difference. The nipple–areola complex visualization was poor in SM (50.34 vs. 76.29% in FFDM), and there were SM-specific artifacts mainly related to the reconstruction algorithm. The radiation dose was higher with SM.

Conclusion FFDM has comparable performance to SM + DBT in diagnostic setup. The latter may be particularly helpful in patients with dense breasts.
Optimal Magnetic Resonance Sequence for Assessment of Central Cartilage Tumor Scalloping
Authors: Shirodkar Kapil K. , Jenko Nathan , Azzopardi Christine , Murphy Jennifer , Patel Anish , James Steven L. , Davies Arthur Mark , Botchu Rajesh
Published: August 2024

Background Magnetic resonance imaging (MRI) is key in evaluating central cartilage tumors. The BACTIP (Birmingham Atypical Cartilaginous Tumour Imaging Protocol) protocol assesses central cartilage tumor risk based on the tumor size and degree of endosteal scalloping on MRI. It provides a management protocol for assessment, follow-up, or referral of central cartilage tumors.

Objectives Our study compared four MRI sequences: T1-weighted (T1-w), fluid sensitive (Short Tau Inversion Recovery (STIR)- weighted, STIR-w), and grayscale inversions (T1-w GSI and short tau inversion recovery [STIR] GSI) to see how reliably endosteal scalloping was detected.

Materials and Methods Two senior consultant musculoskeletal radiologists with experience reviewed randomly selected 60 representative central cartilage tumor cases with varying degree of endosteal scalloping to reflect a spectrum of BACTIP pathologies. The endosteal scalloping was graded as per the definition of BACTIP A, B, and C. They agreed on a consensus BACTIP grade for each of the 240 key images (60 cases × 4 sequences), which was considered the final “consensus” BACTIP grade. These 240 images were then randomized into a test set and given to two fellowship-trained consultant musculoskeletal radiologists for analysis. They assigned a BACTIP grade to each of the 240 selected images while being blinded to the final “consensus” BACTIP grade. The training set was further subdivided into three groups based on the MR image quality (good quality, average quality, and poor quality) to ascertain if the quality of the acquired images influenced intraobserver and interobserver agreements on the BACTIP grading. The two observers were blinded to the grade assigned to the image quality.

Results Linearly weighted kappa analysis was performed to measure the agreement between the BACTIP grading answers by two observers and the “consensus” BACTIP grading answers, as well as the BACTIP grading agreement between the two observers themselves. The analysis revealed that T1-w and STIR-w sequences demonstrated more consistent and higher agreement across different image qualities. However, the T1-w GSI and STIR-w GSI sequences exhibited lower agreement, particularly for poor-quality images. T1-w imaging demonstrated substantial agreement between BACTIP gradings for poor-quality images, suggesting potential resilience of T1-w sequence in challenging imaging conditions.

Conclusion T1-w imaging is the best sequence for BACTIP grading of endosteal scalloping, followed by fluid-sensitive STIR sequences.
Evaluation of the Articular Disc Using the Magnetic Resonance Cartigram in Asymptomatic and Symptomatic Temporomandibular Disorders
Authors: Sivakumar Aparna , Ganesan Anuradha , Lakshmi Krithika Chandrasekar , Aniyan Yesoda , Kannan Saravanan
Published: August 2024

Objectives The study is aimed to perform magnetic resonance (MR) cartigram of the articular disc in patients with asymptomatic and symptomatic temporomandibular disorders (TMD).

Materials and Methods Thirty-nine volunteers were divided into three groups: 16 symptomatic TMD, 16 asymptomatic TMD, and 7 controls. The articular disc was divided into three segments (anterior, middle, and posterior) and analyzed using morphological magnetic resonance imaging (MRI) and T2 mapping sequences. T2 relaxation values were measured and assessed by an experienced radiologist and two observers. The T2 values in the discs were compared between the control, asymptomatic, and symptomatic groups using the Kruskal–Wallis test. The right and left discs were compared using the Wilcoxon signed rank test. Inter-examiner reliability among different examiners was evaluated.

Results The controls had the highest T2 values compared with the other groups. The comparison among the right and left sides of all the groups revealed statistically significant results in the anterior portion in the asymptomatic group and the middle portion in the symptomatic group (p < 0.05). The inter-examiner reliability coefficients among the three examiners were consistently high, with values of 0.921, 0.920, and 0.930.

Conclusion Our study found the T2 relaxation time span was shorter than that reported in previous studies, which could be attributed to the early stage of cartilage deterioration in the individuals with TMD inferring treatment at this phase may be eventually effective with a good prognosis.
Granular Cell Tumor of the Anal Canal: Case Report and Literature Review
Authors: Prats Jorge Arche , Prado Diego García , Villegas Gonzalo Campaña , Mardónez Mónica Martínez
Published: August 2024

Granular cell tumors (GCTs) are rare benign neoplasms that can occur anywhere in the body but are most commonly found in the head and neck region. These tumors are often asymptomatic and are incidentally discovered during routine rectal examination. In some cases, symptoms may include bleeding, pain, and a palpable mass. Imaging studies such as colonoscopy, ultrasound, magnetic resonance imaging (MRI), or computed tomography can be used to characterize and measure the tumor. Treatment typically involves local resection, with or without adjuvant radiotherapy, depending on the size, location, and pathological characteristics of the tumor. The prognosis for GCTs of the anal canal is generally good, with few cases of recurrence or metastasis reported, but long-term follow-up is recommended due to the potential for late recurrence or malignant transformation. The present study reports a 39-year-old female patient who presented with anal itching associated with protrusion of a perianal mass and who underwent treatment between November 2022 and December 2023. The MRI scan revealed a nodular image in its caudal aspect with involvement of the internal sphincter between 12 and 5 o'clock, which was successfully resected. Histopathology was compatible with GCT, and the patient had a satisfactory recovery and was discharged. In conclusion, GCTs of the anal canal are rare and extremely unusual tumors that can be difficult to diagnose and manage, requiring a multidisciplinary approach for optimal management.
Refractive channeling of heating wave driven by laser beam interaction with plasma of subcritical density
Authors: Gus'kov S. Yu. , Kuchugov P. A. , Demchenko N. N.
Published: August 2024

The phenomenon of laser-driven heating wave propagation in a plasma with a density less than the critical density is considered for the case of a finite radius of the laser beam. Based on computational and theoretical studies, the effect of channeling the heating wave propagation in the central axial region of plasma due to the reflection of laser radiation on density gradient, formed by plasma motion, at the tuning point was found. Unlike the self-focusing phenomenon, where the laser flux is concentrated without ray intersection, in refractive channeling, this occurs due to ray intersection. This is similar to the creation of a high flux density during multi-beam irradiation of the laser target. It is shown that the longitudinal velocity of heating wave in the channeling region is significantly larger compared with that in the peripheral plasma regions located at a distance of about laser beam radius.
Investigation of the solar cell materials Cu(In,Ga)Se2 and Cu2ZnSnS4 with muon spin spectroscopy and density-functional calculations
Authors: Vilão R. C. , Marinopoulos A. G. , Santos D. G. , Alberto H. V. , Gil J. M. , Mengyan P. W. , Kauk-Kuusik M. , Lord J. S. , Weidinger A.
Published: August 2024

Cu(In,Ga)Se2 (CIGS) and Cu2ZnSnS4 (CZTS) are potential absorber materials for solar cell applications. We report an investigation of these materials using muon spin spectroscopy. In these experiments, positive muons produced at accelerator facilities (here the ISIS Facility, Rutherford Appleton Laboratory, U.K.) are implanted into the material and come to rest at interstitial sites in the host lattice. The muon is a sensitive local probe to study materials properties on an atomistic level. An advantage of the method is that interface properties can be studied by placing the probe particles at different depths in the sample. Muonium, the positive muon with an electron, can be considered as a light isotope of hydrogen (mass ratio 1/9) with almost identical electronic properties to hydrogen. Thus, muon spectroscopy provides also information about hydrogen in the host material. The aim of the present experiment is to obtain information about the muonium/hydrogen states formed in CIGS and CZTS solar cell materials. A major goal of the experiment is to obtain information about the physical embedding process of the implanted particle into the host lattice. The present study combines experimental measurements with total energy calculations in the framework of density functional theory. We obtain the final configurations of muonium in CZTS, that we discuss in parallel to those in CIGS. This allows us to deepen our understanding of the influence of the hydrogen impurity on the properties of these materials. We also discuss the final steps in the process of muon implantation in these materials.
Evolution of liquid phase during homogenous non-equilibrium melting of Ta at superheating temperature
Authors: Wang Yihan , Shao Tianmin
Published: August 2024

Homogenous melting at superheating temperature is commonly described by classical nucleation theory (CNT), but the atomic mechanism of the formation and development of critical liquid nuclei is still unclear. Molecular dynamics simulations were conducted to analyze the melting process of Ta. It is found that the process of subcritical liquid clusters evolving into critical liquid nucleus occupies most of the melting time, and merging between neighboring liquid clusters is the main path for subcritical liquid clusters to grow in size. Total melting time is strongly affected by the distribution of formation sites of subcritical liquid clusters, which has been considered random in homogenous melting. This work depicts a clear picture of the formation and development of liquid phase during the homogeneous melting process at superheating temperature and suggests an internal factor of melting mechanism.
Erythrocyte membrane-camouflaged magnetic and up/downconverting nanoparticles for photothermal therapy and luminescent nanothermometry
Authors: Vinícius-Araújo Marcus , Sousa Lucas Ribeiro de , Santana Ricardo Costa de , Mendanha Sebastião Antonio , Bakuzis Andris Figueiroa
Published: August 2024

Cell-membrane-coated nanoparticles (NPs) have important applications in the prevention, diagnosis, and treatment of diseases. Here, we demonstrate the preparation of a multifunctional membrane camouflage system consisting of Zn-Mn ferrite and rare-earth (Nd, Yb, and Ho)-doped fluoride NPs encapsulated into the red blood cell membrane (RBCm). Energy-dispersive spectroscopy and transmission electron microscopy of the RBCm showed the encapsulation of the magnetic and fluorescent fluoride NPs. The magnetic properties of the nanocarrier showed superparamagnetic behavior as a result of the ferrite NP and diamagnetic contribution as a result of the membrane constituents. Magnetic nanoparticle hyperthermia was found to have a lower efficiency compared to photothermal therapy (PTT) under the conditions evaluated. The photothermal conversion efficiency is found to be around 13% (excitation at 808 nm). MNH and PTT properties arise from the magnetic NPs, while the luminescent properties arise from the rare-earth-doped fluoride NPs. The Nd ions in the fluoride NP are excited at 808 nm, avoiding nonspecific tissue heating. Down-conversion peaks are related to Nd/Yb emissions, whereas upconversion peaks arise from Ho states as a result of energy transfer processes. Potential multiparametric luminescence thermometry based on the emission of Yb3+/Nd3+ intensity ratio (980/1060 nm) provides encouraging results for real-time monitoring of thermal therapy in the second biological window. The thermal sensitivity ranged from 0.58 to 0.62%K−1 at the range of 45–60 °C.
Purcell effect for high-Q plasmon lattice modes in the coupled dipole approximation
Authors: Vurgaftman I. , Tsoi S.
Published: August 2024

We present a semi-analytical treatment of the spontaneous emission enhancement for collective lattice resonances of a linear 1D array of metallic nanoparticles in order to improve the physical understanding of these resonances, previously explored numerically. The treatment is based on the coupled-dipole approximation and Green's function formalism. We calculate the Purcell factor of the surface lattice resonance for localized emitters as a function of emitter position and compare it to the resonant enhancement for a localized plasmonic resonance of an isolated single nanoparticle. We find that the Purcell factor for a single emitter (or an incoherent ensemble of emitters) near the nanoparticle is typically smaller for the surface lattice resonance, although it can be higher for emitters nearly halfway between the particles. Nevertheless, in agreement with previous models, the lattice resonances display stronger emission in certain regions as well as a much narrower range of emission angles, which can lead to improved collection efficiency. Finally, we show that the “slow-propagating” modes of square 2D lattices of nanoparticles are capable of significantly stronger Purcell-enhanced emission.
Transport properties and kinetic coefficients of copper thermal plasmas
Authors: Krivtsun I. V. , Momot A. I. , Denysenko I. B. , Mokrov O. , Sharma R. , Reisgen U.
Published: August 2024

The transport and kinetic coefficients of copper plasma are studied. The temperature dependences of momentum transfer cross sections, collision frequencies (electron–atom, ion–atom), ionization and recombination rates, thermal diffusion, and thermal and electrical conductivity coefficients are calculated. Formulas are proposed that approximate the results of calculations with high accuracy. The temperature dependence of electrical and thermal conductivity is studied and compared with literature data. The obtained coefficients are necessary for the description of transfer processes in a copper non-equilibrium plasma.
Water structures in tip-charged carbon nanotubes
Authors: Ono Yûi , Yamamoto Eiji , Yasuoka Kenji
Published: August 2024

Carbon nanotubes (CNTs) have potential applications in separation membranes and nanofluidic devices. It is well known that the behavior of water molecules confined in CNTs is affected by surface functional groups and external electric fields, leading to structural changes. The understanding of these structural changes of water within various CNTs is crucial, particularly in the context of material separation. While there have been many investigations into the effects of individual specific functional groups, a comprehensive understanding of the effect of these functional groups and the electric fields they generate on water molecules remains elusive. In this study, we investigate the properties of water molecules in tip-charged CNTs of (8,8), (10,10), and (12,12) chiral vectors with positive charges at one tip and negative charges at the other tip. Abstraction of ionized functional groups as tip charges enables a comprehensive understanding that is independent of individual functional groups. The symmetrically arranged tip-charges spontaneously generate a strong and symmetric electric field in the CNTs. However, the strength and directionality of the electric field are non-uniform and complex. In the interiors of (8,8) and (10,10) tip-charged CNTs, helical and square structures, which have disturbances caused by the non-uniformity of the electric field, are observed. The properties of the water molecules differed significantly in the center of the CNTs and near positive and negative charges, despite the electric field symmetry. In (12,12) tip-charged CNTs with 12 charges, a local ring structure is observed in the vicinity of negative charges but not in the vicinity of positive charges. It is concluded that the water structures in tip-charged CNTs have different characteristics from those in plain CNTs under a uniform electric field.
Insights into optical absorption and dark currents of the 6.1 Å type-II superlattice absorbers for MWIR and SWIR applications
Authors: Singh Anuja , Muralidharan Bhaskaran
Published: August 2024

A holistic computational analysis is developed to calculate the quantum efficiency of InAs/GaSb superlattice-based photodetectors. Starting with the electronic band characteristics computed by taking InSb/GaAs at the interface using the 8-band k.p approach, we demonstrate the impact of InAs and GaSb widths on the bandgap, carrier concentration, and the oscillator strength for type-II superlattice absorbers. Subsequently, the alteration of these characteristics due to the extra AlSb layer in the M superlattice absorber is investigated. Extending our models for determining TE- and TM-polarized optical absorption, our calculations reveal that the TE-polarized absorption shows a substantial influence near the conduction-heavy hole band transition energy, which eventually diminishes, owing to the dominant TM contribution due to the conduction-light hole band transition. Extending our analysis to the dark currents, we focus mainly on Schokley–Read–Hall recombination and radiative recombination at lower temperatures and show that Schokley–Read–Hall dominates at low-level injection. We show that short-wavelength and mid-wavelength M superlattice structures exhibit higher quantum efficiency than the corresponding same bandgap type-II superlattice with the lower diffusion dark current. Furthermore, we analyze the density of states blocked by the barrier, crucial for XBp photodetector after absorber examination. Our work, thus, sets a stage for a holistic and predictive theory aided analysis of the type-II superlattice absorbers, from the atomistic interfacial details all the way to the dark currents and absorption spectra.