bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiative acceleration calculation methods and abundance anomalies in Am stars
Authors: Hui-Bon-Hoa Alain
Published: October 2024

Context. Atomic diffusion with radiative levitation is a major transport process to consider to explain abundance anomalies in Am stars. Radiative accelerations vary from one species to another, yielding different abundance anomalies at the stellar surface.

Aims. Radiative accelerations can be computed using different methods: some evolution codes use an analytical approximation, while others calculate them from monochromatic opacities. We compared the abundance evolutions predicted using these various methods.

Methods. Our models were computed with the Toulouse-Geneva evolution code, in which both an analytical approximation (the single-valued parameter method) and detailed calculations from Opacity Project (OP) atomic data are implemented for the calculation of radiative accelerations. The time evolutions of the surface abundances were computed using macroscopic transport processes that are able to reproduce observed Am star surface abundances in presence of atomic diffusion, namely an ad hoc turbulent model or a global mass loss.

Results. The radiative accelerations obtained with the various methods are globally in agreement for all the models below the helium convective zone, but can be much greater between the bottom of the hydrogen convective zone and that of helium. The time evolutions of the surface abundances mostly agree within the observational error, but the abundance of some elements can exceed this error for the least massive mass-loss model. The gain in computing time from using analytical approximations is significant compared to sequential calculations from monochromatic opacities for the turbulence models and for the least massive wind model; the gain is small otherwise. Test calculations of turbulence models with the tabulated OPAL opacities yield quite similar abundances as OP for most elements but in a much shorter time, meaning that determining Am star parameters can be done using a two-step method.
The persistent Be enigma: The case of HD 212044
Authors: Pereira Alan W. , Janot-Pacheco Eduardo , Andrade Laerte , Emilio Marcelo
Published: October 2024

We present an analysis of the Be star HD 212044 that reveals intriguing correlations between photometric variations, circumstellar disk emission, and frequencies. Our findings, based on data from the Transiting Exoplanet Survey Satellite (TESS) mission, show an unexpectedly strong negative correlation between photometric brightness and Hα equivalent width, challenging the established understanding of the behavior of Be star seen at low inclination angles. Notably, beating episodes precede brightening events. This study suggests that the variability of HD 212044 may be due to additional mechanisms.
Retrospective study on patient comfort and post-operative condition associated with intravenous sedation versus general anesthesia for third molar extraction in ambulatory surgery in a state hospital
Authors: Légroz Eloise , Bratiloveanu Petre Lupu , Varazzani Andrea
Published: October 2024

Objectives: Third molar extraction requires local or general anesthesia. In public hospitals, general anaesthesia is frequently used to perform the most complex extractions and to accommodate patients' wishes. However, the choice of general anesthesia is at the discretion of the care center. Intravenous sedation is also an option. We suggest that comfort and post-operative condition are better in patients undergoing sedation rather than general anesthesia. This study aimed to evaluate the comfort and post-operative condition after third molar extraction in an 18–50-year-old ambulatory surgical population in a state hospital. Method and materials: In the stomatology and maxillofacial surgery department of Roanne Hospital, two anesthetic protocols are used for third-molar extraction. We retrospectively collected 47 patients who underwent third molar extraction between 1st July 2022 and 31st December 2022. Results were collected by questionnaires and data were retrospectively retrieved from medical records. Results: Twenty patients underwent a general anesthesia and twenty-seven underwent intravenous sedation. The study found no difference for the pain level (p < 0.62) between the two anesthesia techniques. The comparison of the approaches indicated that intravenous sedation required a shorter duration of anesthesia (p < 0.0001) and a shorter time in the recovery room (p < 0.0001). Conclusion: This study indicates the feasibility and the effectiveness of intravenous sedation for patients undergoing third molar extraction in a state hospital. As other studies in the literature that have shown greater satisfaction and better recovery in patients undergoing intravenous sedation compared with general anesthesia.
Interdisziplinäre Empfehlungen für die Entwicklung von
Gesundheitskiosken als niedrigschwellige, kommunale
Versorgungsstrukturen
Authors: Kutschke Geraldine , Kutschke Lea , Sauder Lena , James Alice , Woelwer Stefan , Gehr Sinje
Published: October 2024

Das Bundesministerium für Gesundheit hat in einem Eckpunktepapier vom 31. August
2022 den Aufbau von 1.000 Gesundheitskiosken bundesweit ausgerufen [1]. Das Ziel
dieser Initiative ist es, den Zugang zur gesundheitlichen Versorgung
insbesondere für Menschen mit besonderem Unterstützungsbedarf in sozial
benachteiligten Regionen sicherzustellen und gezielt zu koordinieren. Das
Initiativrecht zur Errichtung und Trägerschaft derartiger Gesundheitskioske
obliegt den Kommunen, die Finanzierung soll jedoch mehrheitlich von den
gesetzlichen und privaten Krankenkassen übernommen werden. Offen ist jedoch, wie
diese Gesundheitskioske konkret regional ausgestaltet werden sollen. Das hier
vorgestellte interdisziplinäre Mixed-Methods-Forschungsprojekt aus der
gesundheitsbezogenen Sozialen Arbeit und den Designwissenschaften geht der
Forschungsfrage nach, wie ein Gesundheitskiosk unter den derzeitigen
Voraussetzungen ausgestaltet werden kann. Es liefert den Kommunen im
Ergebnisteil einen Methodenkatalog zur Förderung interdisziplinärer
Zusammenarbeit sowie praktische Empfehlungen und prototypische
Gestaltungsvorschläge im Sinne einer Blaupause für die eigenständige Entwicklung
und Einführung von regional angepassten Gesundheitskiosken.
Gender- and personality-specific differences in academic qualifications, research motivation, and attractiveness of leadership positions: a survey among radiologists from Germany
Authors: Molwitz Isabel , Kemper Christoph , Stahlmann Katharina , Yamamura Jin , Adam Gerhard , Langenbach Marcel Christian , Reim Martin , Wegner Franz , Bannas Peter , Lotz Joachim , Can Elif , Zagrosek-Regitz Vera , Hamm Bernd , Keller-Yamamura Sarah
Published: October 2024

This study investigated gender- and personality-specific differences in academic qualifications, research motivation, and options to increase the attractiveness of leadership positions in radiology.

A validated questionnaire with 66 questions was distributed via the German Roentgen Society and individually sent to 4,500 radiologists in Germany. Participants were asked about their gender. Personality dimensions were assessed using the OCEAN (Big Five) model. Multivariable regression analyses were employed.

Of 510 included participants (women 237 (46.5%)), men were four times more likely to have acquired an associated professorship (AP, Habilitation Privatdozent) ((odds ratio (OR) 4.39 (2.22–8.67)). Also, they planned to achieve an AP more frequently (OR 2.87 (1.47–5.61)). The only gender-specific motivator for an AP was the option to become eligible for the position of chief physician (men OR 2.56 (1.07–6.15)). Mentors increased the probability of acquiring an AP (OR 2.07 (1.13–3.80)) or striving for an AP (4.82 (2.39–9.73)). Female mentees were likelier to have female mentors (OR 4.62 (1.68–12.73)). To increase the attractiveness of leadership positions, female radiologists perceived gender balance at the management level (OR 3.32 (2.28–4.82)), top sharing (OR 2.22 (1.48–3.32)), and better work-life balance (OR 2.02 (1.19–3.43)) as more relevant than male radiologists. More pronounced openness (OR 1.62 (1.10–2.38)) and extroversion (OR 1.45 (1.07–1.97)) were positively associated with planning an AP. More pronounced agreeableness (OR 0.67 (0.50–0.91)) was negatively associated.

Research motivation is mainly independent of gender. Academic qualification varies with gender and personality dimensions. Mentoring, female role models, top sharing, and better work-family compatibility could motivate women to pursue academic leadership.
Duty of Candour legislation in post-colonoscopy colorectal cancer: a prospective cohort study
Authors: Saunsbury Emma , Burr Nicholas E. , Beaton David , McSweeney Kate , Mason-Higgins Jo , Trudgill Nigel , Morris Eva J. A. , Valori Roland
Published: October 2024

Background This study investigated the application of Duty of Candour (DoC) legislation in the context of post-colonoscopy colorectal cancers (PCCRCs). DoC mandates transparent disclosure of notifiable safety incidents to patients in the English National Health Service, including incidences leading to severe or moderate harm. This study aimed to analyze the application of DoC in PCCRCs, improve understanding of the legislation, and identify challenges in DoC implementation.

Methods A national audit of PCCRCs was conducted between September 2021 and May 2022. PCCRCs were identified using linked administrative datasets, and root-cause analyses were performed using structured templates. “Avoidability” and harm were categorized into specific levels, and guidance was provided on improving consistency in judgments.

Results 16% of 1724 PCCRCs resulted in major harm or death, of which 27% (75) were probably or definitely avoidable. Hospitals deemed DoC discharge necessary in only 53% of these cases. When including moderate harm, 11% of all PCCRCs would trigger DoC discharge, yet this was deemed necessary in only 45% of such cases.

Conclusions There is inconsistent application of DoC in PCCRC cases. Challenges include determining “avoidability” and harm, particularly when diagnosis is delayed. Clearer guidance and definitions of harm are needed to improve adherence to regulations.
Rare-Earth-Metal-Catalyzed Regioselective Hydrosilylation of Internal Alkenes and Alkynes
Authors: Dong Shunxi , Zhu Chenhao , Mao Tao , Feng Xiaoming
Published: October 2024

A highly regioselective hydrosilylation reaction of internal alkenes was achieved by using commercially available lanthanum hexamethyldisilazane (La(HMDS)3). Notably, the Z- or E-configuration of internal alkenes has negligible influence on either the reactivity or regioselectivity. Internal alkynes could also be used, affording the mono di-hydrosilylation product in the presence of La(HMDS)3 or mono-hydrosilylation product with Y(HMDS)3 as the promoter.
Asymmetric Synthesis of 3,3′-Pyrrolidonyl Spirooxindole-5′-Carboxylic Ester from l-Tryptophan
Authors: Hajra Saumen , Hazra Atanu , Maity Dhananjoy , Bhosale Suhas S.
Published: October 2024

A highly efficient, multi-gram scale asymmetric synthesis of 3,3′-pyrrolidonyl spirooxindole-5′-carboxylic ester, which could be a potential precursor for the synthesis of cyanogramide, is accomplished from commercially available l-1-methyltryptophan in two pots. Fluoride-promoted desilylative spiro-cyclization of (semi) in situ generated isocyanate derived from l-1-methyltryptophan is the key reaction. Further, a variety of arene-substituted 3,3′-pyrrolidonyl spirooxindole-5′-carboxylxic acid esters were synthesized by late stage functionalization of easily accessible 3,3′-pyrrolidonyl spirooxindole-5′-carboxylic ester.
Pattern and Predictors of Neurologic Comorbidities Among African Children with Epilepsy
Authors: Uhunmwangho-Courage Aderonke O. , Lagunju Ikeoluwa A. , Ejeliogu Emeka U. , Bode-Thomas Fidelia , Uhunmwangho Courage U. , Ofakunrin Akinyemi O.D.
Published: October 2024

Background Epilepsy is the most common neurologic disorder affecting children in Nigeria. It is often associated with other neurologic comorbidities in addition to epileptic seizures, such as attention deficit hyperactivity disorder (ADHD) and cognitive, visual, and hearing impairments, which can be unrecognized while focusing on the seizures.

Methods This cross-sectional study assessed the prevalence, pattern, and predictors of neurologic comorbidities among 100 children with epilepsy (CWE) attending the pediatric neurology clinic of Jos University Teaching Hospital, Jos, Nigeria, and age- and sex-matched controls selected consecutively. Data were summarized using frequencies and proportions. Chi-squared and Mann–Whitney U tests were used to test the categorical values, while logistic regression was used to determine the predictive factors for neurologic comorbidities.

Results The prevalence of neurologic comorbidities among CWE versus controls was 65 vs. 15% (p < 0.001). Factors associated with neurologic comorbidities in CWE include younger age at onset of epileptic seizures (p < 0.003), severity of seizures (p < 0.001), history of status epilepticus (p < 0.044), background history of intracranial infections (p < 0.029), and the use of combination antiepileptic drugs (p < 0.001). Predictors of comorbidities in CWE were treatment with sodium valproate and polytherapy.

Conclusion Neurologic comorbidities are more frequent among CWE than controls; therefore, screening for neurologic comorbidities should be routine when assessing and managing CWE.
Interventions for Fluid Collections in Acute Pancreatitis: Expanding Horizon
Authors: Kulariya Manit , Gupta Pankaj , Jearth Vaneet , Singh Harjeet , Singh Anupam , Shah Jimil , Samanta Jayanta , Mandavdhare Harshal , Sharma Vishal , Sinha Saroj K. , Dutta Usha
Published: October 2024

Managing pancreatic fluid collections (PFCs) in acute pancreatitis has undergone a paradigm shift. Endoscopic and surgical advancements have led to the development of safer and more effective techniques for draining PFCs and performing necrosectomy. These techniques have been effectively incorporated into the step-up approach. Percutaneous catheter drainage remains the cornerstone for managing PFCs, although its role has changed with the advent of endoscopic ultrasound-guided techniques. PFC management relies heavily on interdisciplinary collaboration. All the techniques must be considered complementary rather than competitive. The preference for one method over the other must consider the patient factors and availability of expertise. This review entails a detailed discussion of the intervention of PFCs with the latest available evidence.
Strong vs. stable: the impact of ESG ratings momentum and their volatility on the cost of equity capital
Authors: Magnani Monia , Guidolin Massimo , Berk Ian
Published: October 2024

We test whether in the cross-section of European stocks, the cost of equity capital is more strongly affected by the (upward) “slope” (identified as momentum over a period of time) of their ESG scores or by their “stability” (identified as the volatility of the scores over a period of time), measured around a given slope. We find that short-term ESG momentum is priced in the cross-section of stock returns but that it may increase or decrease the ex-ante cost of capital depending on the specific sample investigated. While short-term ESG momentum may represent a novel, priced systematic risk factor, there is also strong evidence that a ESG spread strategy that buys (sells) low (high) ESG score volatility stocks leads to a significant alpha and lower the ex-ante cost of capital. This suggests that ESG rating stability may carry a more reliable reward than improvements do, in terms of ex-ante equity cost of capital. These results are robust to the use of different sub-samples (over firms and sub-periods) and to forming the two quantitative ESG signals on the basis of alternative rating data.
Screening participants with inflammatory bowel disease or high colorectal cancer risk in Denmark: a cohort study
Authors: Therkildsen Signe Bülow , Larsen Pernille Thordal , Njor Sisse Helle
Published: October 2024

Individuals with inflammatory bowel disease (IBC) and high-risk individuals are advised to discuss participation with their doctor and not to participate in colorectal cancer (CRC) screening. Yet a substantial proportion still participate in the Danish faecal immunochemical test (FIT) screening and have a higher positive FIT rate than the average-risk population. We estimated the risk of false-positive screening among individuals with inflammatory bowel disease and high-risk individuals to improve recommendations regarding screening participation. We included 71,871 FIT-positive participants (2014–2017) who had a subsequent colonoscopy within 3 months. Screening outcome within 180 days was established by using registers. We determined that 26,591 of the included participants had a false-positive screening. Participants with IBC or high CRC risk had a significantly higher risk of getting a false-positive screening than the average risk population, resulting in too many screening-related colonoscopies being performed among these individuals, indicating a need to update the screening protocols.
Evolving techniques for enhanced estimation: A comprehensive survey of stratified sampling and post-stratification methods
Authors: Triveni G. R. V. , Danish Faizan , Tawiah Kassim
Published: October 2024

This comprehensive review delves into the landscape of estimators used in stratified sampling and post-stratification to estimate crucial population parameters, such as mean, median, variance, proportion, and distribution function. This study extensively examines the utilization of single and double auxiliary information, calibration weights, and various classes of estimators in the context of survey sampling, shedding light on their strengths and limitations. While these methods contribute significantly to enhancing estimation accuracy within stratified populations, this Review underscores challenges such as the dependence on accurate auxiliary information for single and double auxiliary methods, the assumption of ignorable nonresponse in calibration weights, and the need for careful consideration of underlying assumptions in a class of estimators. Future work in this field should focus on refining and validating these methodologies, addressing potential biases, and exploring innovative ways to handle nonresponses. Rigorous sensitivity analyses and investigations into the robustness of these techniques under varying conditions will be essential for advancing the precision and reliability of parameter estimation in the complex landscape of stratified sampling and post-stratification. This Review serves as a foundational resource for researchers and practitioners engaged in advancing the field and navigating the nuances of precise parameter estimation in survey sampling.
Semiclassical perturbations of single-degree–of–freedom Hamiltonian systems I: Separatrix splitting
Authors: Ohsawa Tomoki , Yagasaki Kazuyuki
Published: October 2024

We study semiclassical perturbations of single-degree-of-freedom Hamiltonian systems possessing hyperbolic saddles with homoclinic orbits, and provide a sufficient condition for the separatrices to split, using a Melnikov-type approach. The semiclassical systems give approximations of the expectation values of the positions and momenta to the semiclassical Schrödinger equations with Gaussian wave packets as the initial conditions. The occurrence of separatrix splitting explains a mechanism for the existence of trajectories to cross the separatrices on the classical phase plane in the expectation value dynamics. Such separatrix splitting does not occur in standard systems of Hagedorn and Heller for the semiclassical Gaussian wave packet dynamics as well as in the classical systems. We illustrate our theory for the potential of a simple pendulum and give numerical computations for the stable and unstable manifolds in the semiclassical system as well as solutions crossing the separatrices.
Assessing physics-informed neural network performance with sparse noisy velocity data
Authors: Satyadharma Adhika , Chern Ming-Jyh , Kan Heng-Chuan , Harinaldi  , Julian James
Published: October 2024

The utilization of data in physics-informed neural network (PINN) may be considered as a necessity as it allows the simulation of more complex cases with a significantly lower computational cost. However, doing so would also make it prone to any issue with the data quality, including its noise. This study would primarily focus on developing a special loss function in the PINN to allow an effective utilization of noisy data. However, a study regarding the data location and amount was also conducted in order to allow a better data utilization in PINN. This study was conducted on a lid-driven cavity flow at Re = 200, 1000, and 5000 with a dataset of less than 100 velocity data and a maximum noise of 10% of the maximum velocity. The results show that by ensuring the data are distributed in a certain configuration, it has zero noise, and by using as much data as possible, the computational cost of PINN can be significantly reduced compared to without using any data at all. For Re = 200, it is 7.4 faster by using data, and this speedup is potentially higher for higher Re cases. For the noise in particular, it does not only make the PINN more inaccurate but also necessitate the usage of more data as this is the only way to make it more accurate. This issue though is capable to be solved with our new method, which only uses the data as an approximate solution, and the governing equation would figure out the details. This method was also shown to be capable to improve the PINN accuracy with the potential to almost completely eliminating the noise effect.
Epitaxial RuO2 and IrO2 films by pulsed laser deposition on TiO2(110)
Authors: Keßler P. , Waldsauer T. , Jovic V. , Kamp M. , Schmitt M. , Sing M. , Claessen R. , Moser S.
Published: October 2024

We present a systematic growth study of epitaxial RuO2(110) and IrO2(110) on TiO2(110) substrates by pulsed laser deposition. We describe the main challenges encountered in the growth process, such as a deteriorating material flux due to laser-induced target metallization or the delicate balance of under- vs over-oxidation of the “stubborn” Ru and Ir metals. We identify growth temperatures and oxygen partial pressures of 700 K, 1 × 10−3 mbar for RuO2 and 770 K, 5 × 10−4 mbar for IrO2 to optimally balance between metal oxidation and particle mobility during nucleation. In contrast to IrO2, RuO2 exhibits layer-by-layer growth up to 5 unit cells if grown at high deposition rates. At low deposition rates, the large lattice mismatch between film and substrate fosters initial 3D island growth and cluster formation. In analogy to reports for RuO2 based on physical vapor deposition [He et al., J. Phys. Chem. C 119, 2692 (2015)], we find these islands to eventually merge and grow to continue in a step flow mode, resulting in highly crystalline, flat, stoichiometric films of RuO2(110) (up to 30 nm thickness) and IrO2(110) (up to 13 nm thickness) with well-defined line defects.
A dual-stator threaded linear ultrasonic motor with preload mechanism
Authors: Zhang Gaoren , Qin Hongfei , Wang Zhongying , Liu Menghui , Yu Zhengxiang , You Lei , Yang Yuhan
Published: October 2024

The cylindrical ultrasonic motor, noted for its straightforward design, ease of miniaturization, and high precision, has significant potential in fields such as optics, healthcare, and precision engineering. However, miniaturization presents challenges, including diminished output force and complications in applying preloading stress. To address the reduced output force, this study presents a dual-stator, high-thrust cylindrical linear ultrasonic motor. This innovative motor features two stators, a mover, and a mechanism for applying preloading stress. A key design element is the parallel arrangement of the two stators along a threaded output shaft, separated by elastic components. This setup enables axial preloading via the threads’ engagement. Simulations were conducted to refine the stators’ parameters, assess their operational modes, and evaluate their in-plane paths. A prototype was subsequently built to test its impedance characteristics and mechanical performance. Test results showed that under a 200 Vpp drive, the single-stator motor generated a maximum force of 4.3 N, while the dual-stator configuration produced 6.8 N. After applying preloading stress, the output force of the dual-stator motor increased to 9.4 N.
Cathodic arc deposited tetrahedral amorphous carbon as thin film contact pressure sensing material
Authors: Haikola Juha , Kolehmainen Jukka , Tervakangas Sanna , Tittonen Ilkka
Published: October 2024

Tetrahedral amorphous carbon (ta-C) film was deposited using the filtered pulsed cathodic arc deposition method. The ta-C structures deposited on high velocity oxygen fuel thermally sprayed steel beam substrates were investigated for piezoresistive properties under direct contact pressing. A load of up to 1.4 GPa was applied with point contact, with no detrimental influence on the material. The linear response for the strain applied homogeneously on the whole film surface and on the local portion of the film surface under a cylindrical contact was observed. A high gauge factor of the measured system of 305 was measured, showing the potential of the material as a good candidate for sensing applications on direct contact measurement devices.
Radiative heat transfer to enhance the performance of liquid metal-based phase change heat sink under natural convection condition
Authors: Li Wei , Li Yuqing , Yao Yuchen , Ren Yue , Bao Wendi , Li Yong , Liu Jing , Deng Zhongshan
Published: October 2024

Liquid metal phase change materials have the advantages of high thermal conductivity and high volumetric latent heat, which are expected to address the growing challenges of thermal management of advanced electronics. In previous studies, the effect of radiative heat transfer from fins of a phase change heat sink on thermal management performance has rarely been considered. In this study, radiative coating materials with high emissivity were prepared and coated on the fins of the liquid metal phase change heat sink. The effect of radiative heat transfer on the performance of liquid metal phase change heat sink was investigated. The experimental results of continuous heating under natural convection conditions show that the introduction of the radiative coating with an emissivity of 0.9298 can extend the time for the surface temperature of the heat source to reach 100 °C by 9.4%, while shortening the recovery time of the phase change heat sink by 14.9%. The results of high-power cyclic heating indicate that the high emissivity coating can reduce the peak temperature by 16.6 °C in the tenth working cycle. A simplified numerical model was subsequently developed and validated to determine the specific effects of phase change and radiative heat transfer on the overall thermal control performance. The radiation-enhanced liquid metal phase change heat sink proposed in this study is simple and maintenance-free. It is expected to address the thermal management issues of electronic devices that cannot use active cooling or operate in thin-air environments.
Quasi-monoenergetic ion acceleration and neutron generation from laser-driven transverse collisionless shocks
Authors: Kordell P. , Zulick C. , Hussein A. E. , Arefiev A. V. , Batson T. , Cobble J. , Glebov V. , Haberberger D. , Stoeckl C. , Nilson P. M. , Krushelnick K. , Willingale L.
Published: October 2024

Experiments using the OMEGA EP laser system were performed to study collisionless shock acceleration of ions driven by the interaction of a relativistically intense laser pulse with underdense plasma. The energy spectrum of accelerated ions in the direction transverse to laser propagation is measured to have several narrow-band peaks which are quasi-monoenergetic with a typical energy bandwidth of 3%. In deuterium plasmas, these ions generate a significant number of fast fusion neutrons. Particle-in-cell simulations confirm that these ions were accelerated by the interaction of transverse shocks and that the appearance of quasi-monoenergetic spectral features depends on the growth of an ion-electron two-stream instability during the interaction.
Thermal conductivity in modified sodium silicate glasses is governed by modal phase changes
Authors: Rasmussen Philip , Sørensen Søren S.
Published: October 2024

The thermal conductivity of glasses is well-known to be significantly harder to theoretically describe compared to crystalline materials. Because of this fact, the fundamental understanding of thermal conductivity in glasses remain extremely poor when moving beyond the case of simple glasses, e.g., glassy SiO2, and into so-called “modified” oxide glasses, that is, glasses where other oxides (e.g., alkali oxides) have been added to break up the network and alter, e.g., elastic and thermal properties. This lack of knowledge is apparent despite how modified glasses comprise the far majority of known glasses. In the present work, we study an archetypical series of sodium silicate [xNa2O–(100 − x)SiO2] glasses. Analyses of modal contributions reveal how increasing Na2O content induces increasing vibrational localization with a change of vibrations to be less ordered and a related general decrease in modal contributions to thermal conductivity. We find the vibrational phases (acoustic vs optical) of sodium vibrations to be relatively disordered compared to the network-forming silicon and oxygen species, explaining how increasing Na2O content decreases thermal conductivity. Our work sheds new light on the fundamentals of glassy heat transfer as well as the interplay between thermal conduction and modal characteristics in glasses.
A perspective on guided electrophoretic transport of particles in liquid crystals
Authors: Sahu Dinesh Kumar , Venkuzhy Sudhakaran Devika , Dhara Surajit
Published: October 2024

Nonlinear electrophoresis in complex fluids like nematic liquid crystals provides new pathways toward achieving precisely controlled motion and assembly of microscopic objects. The nematic host introduces a paradigm shift in the mechanism of electrophoretic transport by generating unbalanced electro-osmotic flows around the colloidal particle due to symmetry breaking of the medium caused by the induced topological defects. Rationally designed particles, which induce various types of defects and asymmetries, provide new opportunities in this regard. In this Perspective article, we discuss how the asymmetry in the shape and interfacial properties help in piloting the particles using an AC electric field. Finally, we propose some feasible strategies to achieve navigational control using magnetic and photo-responsive particles, guided by orthogonal electric, magnetic fields, and light, respectively.
An introduction to the collection ‘Environmental flows in northern Murray–Darling Basin: what we know about the science and management after a decade of practice’
Authors: Southwell M. R. , Frazier P. F. , Peat M. , Banks S. A. , Shrubb J. B. , Kermode T. C. , Thurtell L. A. , Bowen S. , Prior A. E.
Published: October 2024

This paper is the foreword to a collection on monitoring and research outcomes related to water management in the northern Murray–Darling Basin (MDB), Australia. It provides background on the northern MDB, along with a summary of papers presented in the collection. This article belongs to the collection Environmental flows in northern Murray–Darling Basin: what we know about the science and management after a decade of practice.
Phosphatidylserine phospholipase A1 enables GPR34-dependent immune cell accumulation in the peritoneal cavity
Authors: Tam Hanson , Xu Ying , An Jinping , Schöneberg Torsten , Schulz Angela , Muppidi Jagan R. , Cyster Jason G.
Published: October 2024

The peritoneal cavity (PerC) is an important site for immune responses to infection and cancer metastasis. Yet few ligand–receptor axes are known to preferentially govern immune cell accumulation in this compartment. GPR34 is a lysophosphatidylserine (lysoPS)-responsive receptor that frequently harbors gain-of-function mutations in mucosa-associated B cell lymphoma. Here, we set out to test the impact of a GPR34 knock-in (KI) allele in the B-lineage. We report that GPR34 KI promotes the PerC accumulation of plasma cells (PC) and memory B cells (MemB). These KI cells migrate robustly to lysoPS ex vivo, and the KI allele synergizes with a Bcl2 transgene to promote MemB but not PC accumulation. Gene expression and labeling studies reveal that GPR34 KI enhances PerC MemB proliferation. Both KI PC and MemB are specifically enriched at the omentum, a visceral adipose tissue containing fibroblasts that express the lysoPS-generating PLA1A enzyme. Adoptive transfer and chimera experiments revealed that KI PC and MemB maintenance in the PerC is dependent on stromal PLA1A. These findings provide in vivo evidence that PLA1A produces lysoPS that can regulate GPR34-mediated immune cell accumulation at the omentum.
Cyclotron resonance imaging at cryogenic temperatures enabled by electric field modification in a microwave cavity
Authors: Akimoto Ikuko , Suzuki Takayuki , Naka Nobuko , Matsuoka Hideto
Published: October 2024

Cyclotron resonance (CR) is a standard but emerging technique for investigating carrier properties of semiconductors. We have succeeded in CR measurements by employing a microwave cavity designed for electron paramagnetic resonance (EPR). Here, we demonstrate CR imaging to visualize the spatial distribution of carriers at cryogenic temperatures for the first time. To realize CR imaging, it is necessary to account for the electric field modification in the microwave cavity of a cylindrical TM110 mode, which is designed for EPR imaging and is inherently unsuitable for CR measurements. CR detection requires the oscillating electric field perpendicular to the external static magnetic field (B
0) at the sample position, which is not designed for the unloaded cavity. It has been challenging to verify the electric field distribution inside the cavity experimentally, but we show that the observation of the CR signals provides evidence of modification in the electric field. Analysis of the electromagnetic field explains the results, revealing a field distribution whose strength and direction are perturbed due to the lensing effect by the inserted dielectric materials.
Gate-driven transition temperatures of electron hopping behaviors in Hubbard bands formed by dopant-induced QD array in silicon nanowire
Authors: Shang Zimeng , Wang Bowei , Han Weihua
Published: October 2024

Dopant atoms confined in silicon nanoscale channel can be ionized to form quantum dots (QDs). Several dopant atoms couple with each other forming energy bands, where the electron hopping behavior can be described by the Hubbard model. This characteristic renders dopant-induced QDs particularly appealing for applications in nanoelectronic and quantum devices. Herein we study the gate-driven transition temperatures of electron hopping behavior in the upper Hubbard bands (UHBs) and lower Hubbard bands (LHBs) formed by dopant-induced QD array in junctionless silicon nanowire transistors. The gate-dependent transition temperatures are calculated for three stages of electron hopping behaviors including Efros–Shklovskii Variable Range Hopping (ES-VRH), Mott VRH and Nearest Neighbor Hopping (NNH). Our experimental results indicate that the ES-VRH in arrays of dopant atoms occurs in the domination of a long-range Coulomb interaction, in which the hopping distance relies on the Coulomb gap. Furthermore, the localization length of ES-VRH can be modulated by gate voltages. Those factors lead to the significant difference of transition temperatures between the UHBs and LHBs. In addition, we find that the source–drain bias voltage can effectively modulate the transition temperatures between VRH and NNH by thermal activation energies under different bias voltages Vds.
Current signal analysis using SW-GAT networks for fault diagnosis of electromechanical drive systems under extreme data imbalance
Authors: Wang Chaoge , Tian Xinyu , Zhou Funa , Wang Ran , Wang Lijun , Tang Xiaojing
Published: October 2024

In complex industrial environments, ensuring the safe operation and effective maintenance of electromechanical equipment is of paramount importance. Intelligent fault diagnosis based on deep learning is currently the most popular data-driven method. However, conventional intelligent fault diagnosis techniques face several challenges: (1) Most diagnostic models rely heavily on analyzing vibration signals. However, vibration sensors are difficult to deploy in space-constrained environments, and vibration signals are frequently contaminated by strong noise. (2) The prevalence of class imbalance between normal and fault data in equipment condition monitoring can lead to model over-reliance on information from a few classes. (3) Traditional diagnostic models presuppose data independence, neglecting the coupling relationships between data. To address the aforementioned issue, this paper proposes a self-weighted graph attention networks based on motor stator current signal analysis, aimed at solving the fault diagnosis problem of critical transmission components in electromechanical systems under severely imbalanced data scenarios. Firstly, the raw current data is preprocessed using stacked autoencoders, and then the decoded current frequency-domain data is utilized to construct graphical data, thereby enhancing the non-common features and weak fault information in the current signals. Secondly, by introducing the graph pooling attention mechanism into GAT, the model can more effectively focus on useful fault feature information within the graph data. Finally, a novel interclass adjustment loss function is designed to adaptively adjust and balance class weights, enabling the model to pay greater attention to minority class samples and thereby improving the recognition accuracy for minority class faults. Validating the proposed method on two cases and comparing it with other advanced approaches, our method achieved the highest accuracy among the compared methods.
MFHARFNet: multi-branch feature hybrid and adaptive receptive field network for image segmentation
Authors: Li Meng , Yun Juntong , Jiang Du , Tao Bo , Liu Rong , Li Gongfa
Published: October 2024

Accurate segmentation of medical images is crucial for disease diagnosis and understanding disease changes. Deep learning methods, utilizing encoder-decoder structures, have demonstrated cutting-edge performance in various medical image segmentation tasks. However, the pooling operation in the encoding stage results in feature loss, which makes the network lack the ability to fuse multi-scale information at different levels, hinders its effective perception of multi-scale information, and leads to poor segmentation performance. Drawing inspiration from the U-shaped network, this study introduces a multi-branch feature hybrid attention and adaptive receptive field network (MFHARFNet) for medical image segmentation. Building upon the encoder-decoder framework, we initially devise a multi-branch feature hybrid attention module (MFHAM) to seamlessly integrate feature maps of varying scales, capturing both fine-grained features and coarse-grained semantics across the entire scale. Furthermore, we redesign the skip connection to amalgamate feature information from different branches in the encoder stage and efficiently transmit it to the decoder, providing the decoder with global context feature maps at different levels. Finally, the adaptive receptive field (ARF) module is introduced in the decoder feature reconstruction stage to adapt and focus on related fields, ensuring the model’s adaptation to different segmentation target features, and achieving different weights for the output of different convolution kernels to improve segmentation performance. We comprehensively evaluate our method on medical image segmentation tasks, by using four public datasets across CT and MRI. Remarkably, MFHARFNet method consistently outperforms other state-of-the-art methods, exceeding UNet by 2.1%, 0.9%, 6.6% and 1.0% on Dice on ATLAS, LiTs, BraTs2019 and Spine and intervertebral disc datasets, respectively. In addition, MFHARFNet minimizes network parameters and computational complexity as much as possible. The source codes are in https://github.com/OneHundred99/MFHARFNet.
Maximum Fourier spectrum cyclostationarity blind deconvolution and its application in structural health monitoring of power transformers
Authors: He Wen , Qin Limu , Lu Yazhong
Published: October 2024

Power transformer is the most important equipment that affects whether the electric power system can be operated safely and normally, whose condition assessment problem has attracted considerable attention. Background noise frequently affects the effectiveness of nonintrusive techniques based on vibro-acoustic signals for structural health monitoring in power transformers. In this scenario, the Fourier spectrum cyclostationarity index (FSC) is designed based on the cyclostationarity index used for rotating machinery fault diagnosis to construct a maximum FSC blind deconvolution method (MFSCBD) for transformer fault detection in this paper. Firstly, the limitations of the traditional blind deconvolution (BD) in transformer fault detection are discussed in the mathematical principle. Then, a new BD framework based on Kepler optimization algorithm is proposed according to the principle of convex optimization to address the problems of difficulty in solving the complex blind objective function in the traditional differential BD framework and the ill-condition problem in the Rayleigh quotient BD framework. Subsequently, a synthetic nonstationary and nonlinear simulation signal is constructed for numerical verification, and a six-microphone array is designed to obtain the practical signals from the operating transformer to verify the performance of MFSCBD. Finally, the applications on the simulated and experimental signals of power transformers demonstrate that MFSCBD outperforms complete ensemble empirical mode decomposition with adaptive noise and successive variational mode decomposition to some extent for structural health monitoring.
Precision and uncertainty in natural gas calorific value estimation: advanced combinatorial predictive models for complex pipeline systems
Authors: Zhou Jun , Fu Wenqi , Liang Guangchuan , Zhang Daixing , Ma Junjie
Published: October 2024

In recent years, natural gas pipelines have been characterized by multiple intake points, the mixing of different gas sources, and significant variations in gas quality. The existing volumetric measurement system is no longer suitable for the development and operation of natural gas pipelines in China. To ensure accurate and equitable implementation of natural gas measurement, there is a gradual shift towards energy measurement. However, due to numerous measurement interfaces, installing chromatographs at all measurement stations would lead to substantial investment costs. Therefore, predicting the calorific value of natural gas is a key technology for energy measurement. In view of the issues existing in the current methods of obtaining natural gas calorific value, different prediction models of natural gas calorific value are constructed. According to the influencing factors of natural gas calorific value, the uncertainty evaluation is carried out, and the accuracy of different calorific value prediction models is analyzed by case data. The maximum error of regression equation, response surface analysis, BP neural network and genetic algorithm prediction model is 2.29%, 0.43%, 0.59% and 0.45% respectively. However, the combined calorific value (CCV) prediction model is 0.41%. The results indicate that the predicted value calculated by the CCV prediction model is closer to the actual value and has higher prediction performance, which provides a new method for the calorific value prediction and measurement management of natural gas.
Potential for suprathermal chain reactions in degenerate deuterium plasmas at high densities
Authors: Robinson A P L
Published: October 2024

It is argued that fusion chain reactions in the D-D system are feasible with supra-thermal deuterons in the MeV regime, with new generations of deuterons being generated either via neutron-deuteron and proton-deuteron collisions, provided that fuel densities in excess of 1000 gcm−3 are reached. The propagation of supra-thermal deuterons in an infinite, dense deuterium target was studied using a Monte Carlo method that includes multiple nuclear reactions, electron and ion stopping, along with neutron and proton knock-ons. Prior studies into this system are extended and it is shown that : (a)dense pure deuterium may be more supportive of chain reactions via refinements to the ion-ion stopping number, (b) such chain reactions can be supported even when the target is electron degenerate, and (c) the D-T reaction plays a critical role in sustaining these chain reactions.
Critical current characteristics and ampere force distribution of a novel HTS cable with different transposition lengths
Authors: Zhang Heng , Chang Shaonan , Yang Jingyi , Pi Wei
Published: October 2024

Distribution characteristics of the current, ampere force and magnetic flux density (B [T]) of a novel high temperature superconducting (HTS) cable woven by transposed REBCO tapes under different transposition lengths are proposed, and these characteristics of the cable stacked with 3 REBCO tapes are also carried out in this paper for comparison. The objective is to enhance the current density and the compactness of the HTS tapes combination, and uniform the current, ampere force and magnetic flux density (B [T]) distributions. A three-dimensional (3D) finite element model, based on Maxwell’s equations without consideration of the displacement current, is established to describe the state of the system in the liquid nitrogen condition. The distributions characteristics, maximum and minimum values of current, ampere force and magnetic flux density (B [T]) show significant differences in the simulation results between the novel HTS cable woven by 3 transposed REBCO tapes and the cable stacked with 3 REBCO tapes. The simulated results show that the distribution characteristics are improved, with a more uniform distribution characteristic than that of the cable stacked with REBCO tapes. This is due to fully transposed REBCO tapes. In addition, the experimental E–I curve was also reached. The experimental results show that using a shorter transposition length in the cable can improve the critical current. However, a too small transposition length can cause significant damage to the HTS tape, resulting in deformation of the HTS tape and a reduction in the electromagnetic properties of the HTS tape. This affects the critical current of the HTS tape and, ultimately, the critical current of the cable. From the point of view of whether the production process is convenient, meets the requirements of economy and reduces costs, we need to find a suitable transposition length. The measured optimal transposition length is 95 mm for the cable woven by 3 REBCO tapes.