bluuebunny/crossref_metadata_2025 huggingface dataset:
Sustainable Waste Management in Urban Areas using Data Envelopment Analysis
Authors: Kurakova Oksana , Dhyani Manoj , Ganesh Chennakeshi , Thakur Rahul , Al-Fatlawy Ramy Riad , Gupta Gaurav , Choudhary Sunila , Kumar Sunil , Vybhavi Gummagatta Yajaman
Published: October 2024

Utilizing mechanical characteristics, recycling efficiency, and environmental effect as its focal points, this work explores the creation of waste utilizing recycled materials and nanofillers. The green nanocomposite has a tensile strength of 55 MPa, a Young’s modulus of 3.0 GPa, and an impact strength of 6 kJ/m^2, according to the experimental findings, which show that mechanical characteristics are greatly improved when nanofillers are added to recycled plastic matrix materials. After 9 months, tensile strength drops 10%, Young’s modulus drops 20%, and impact strength drops 25%, suggesting that mechanical qualities may deteriorate with time. An evaluation of the green nanocomposite’s recycling efficiency found that it was 90% efficient, meaning that it made good use of waste materials throughout its production. Analyses of environmental impacts show that waste have the ability to be a sustainable alternative to virgin plastic by significantly reducing their carbon footprint, water use, and land use. Green nanocomposite manufacturing with recycled materials and nanofilllers is feasible and environmentally beneficial, according to these results. This research contributes to the conservation of resource es and the concepts of the circular economy in materials science and engineering.
Emotions during elite sport competitions: a descriptive study of the nature, frequency and duration of emotions, and their effects on performance
Authors: Macquet Anne-Claire , Loup Adrien
Published: October 2024

This study presents a descriptive analysis of the emotions experienced by elite fencers during World Cup competitions. It hypothesised that: (a) elite athletes (EAs) would experience a wide panel of emotions corresponding to the valences (positive, negative and surprise), and that these would differ by gender; (b) the duration of emotions would vary; (c) EAs would experience several emotions simultaneously; and (d) experiencing emotions would impact performance. Twelve self-confrontation interviews were conducted with EAs, who were asked to describe their emotions in relation to events observed on a video. Qualitative analysis of interview data explored the nature of the emotions experienced during matches. Quantitative analysis provided results about the frequency of emotions, their duration, co-occurrence, and relationships with performance. Results demonstrated that: (a) there is a large panel of emotions in elite sports, and that gender did not affect emotional valence, (b) the duration of emotions experienced varied, (c) EAs experienced several basis emotions during hit-building sequences, (d) emotions did not appear to influence performance in elite fencing. This research offers preliminary insights into how EAs experienced emotions, and associates this with performance in competitions. It could enrich the emotional approach of coaches and psychologists.
Synergien statt Rivalitäten – die missverstandenen
Rollen von kontinuierlicher intrajejunaler Levodopatherapie und Tiefer
Hirnstimulation in der Behandlung des Morbus Parkinson – eine
Expertenmeinung
Authors: Schröter Nils , Jost Wolfgang H. , Rijntjes Michel , Coenen Volker , Groppa Sergiu , Sajonz Bastian
Published: October 2024

In der Therapie des Morbus Parkinson kommen sowohl die intrajejunale Applikation
von Levodopa/Carbidopa Intenstinalgel (LCIG) und seit kurzem
Levodpoa/Carbidopa/Entacapon Intestinalgel (LECIG) als auch die
Tiefe Hirnstimulation (THS) zum Einsatz. Obwohl diese Verfahren sich in Ihren
Wirkungs- und Nebenwirkungsprofilen sowie dem Zeitpunkt des Einsatzes deutlich
unterscheiden, wird die Therapieeinleitung beider Verfahren häufig
simultan erst bei Erreichen eines fortgeschrittenen Erkrankungsstadiums
geprüft. Aus Sicht der Autoren erreichen Patienten aber mitunter zu
unterschiedlichen Zeitpunkten ihrer Erkrankung die Meilensteine für die
Indikationsstellung eines der jeweiligen Verfahren. Hierbei spielt die
individuelle Krankheitsentwicklung eine tragende Rolle. Die Idee, dass alle
Patienten zu einem bestimmten und definierten Zeitpunkt nahezu gleichzeitig
Kandidat für ein bestimmtes Verfahren werden, erscheint den Autoren als
falsch. Im Rahmen dieser Übersichtsarbeit werden darum die
Therapieformen hinsichtlich ihrer Wirksamkeit für verschiedene
Ziel-Symptome vorgestellt, die simultane Abwägung über den
Zeitpunkt des Einsatzes hinterfragt und eine individualisierte
Therapieevaluation – mit Augenmerk auf Lebensqualität und
gesellschaftliche Teilhabe – abgeleitet mit dem Ziel das Konzept des
„Entweder – Oder“ aufzuweichen und in ein
patientenzentriertes „Welches – Wann“ zu
überführen.
Die Flexionsfraktur des distalen Radius bei Extensionsmechanismus im
Handgelenk
Authors: Selle Christopher , Latz David , Friesen Denis , Schädel-Höpfner Michael
Published: October 2024

Hintergrund Die Einteilung der distalen Radiusfraktur erfolgt in der
klinischen Praxis häufig anhand der vermuteten Unfallmechanismen in
„Extensionsfrakturen“ nach Colles oder „Flexionsfrakturen“ nach Smith. Häufig
liegt nach radiologischen Kriterien eine Flexionsfraktur vor, obwohl die
Patienten eindeutig einen Extensionsmechanismus beschreiben. Auch biomechanische
Untersuchungen lassen vermuten, dass ein Unfall in Extension des Handgelenkes
eine „Flexionsfraktur“ bedingen kann. Das Verständnis zu Entstehung dieser
Fraktur ist unzureichend.

Material und Methoden Zur Beantwortung der Frage, inwieweit
„Flexionsfrakturen“ in Extensionsstellung des Handgelenks entstehen können,
wurden vorhandene Daten von experimentell erzeugten Frakturen ausgewertet. Zur
Verfügung standen Parameter von nicht formalinfixierten, unbehandelten
Humanpräparaten, die im Zeitraum 01.01.2016–31.12.2021 für Osteosynthesekurse
frakturiert wurden. Sowohl die physikalischen Parameter der Frakturerzeugung,
als auch die biologische Beschreibung der verwendeten Präparate wurden mit den
radiologischen Kriterien anhand von Röntgen und Computertomographie
korreliert.

Ergebnisse 122 Präparate mit vollständigem Datensatz wurden ausgewertet,
hierunter fanden sich radiologisch 17 Flexionsfrakturen (13,9%). 10/17 wurden
unter einem Extensionsmechanismus erzeugt, bei einem mittleren Extensionswinkel
von 86,3° (im Vergleich zu 90,5° in der Gruppe der Extensionsfrakturen). Bezogen
auf die 10 Fälle von radiologischen Flexionsfrakturen unter
Extensionsmechanismus lag häufiger eine Pronationsstellung im Handgelenk (6/10)
vor als eine Supinationsstellung (1/10). Flexionsfrakturen zeigten im Mittel
eine niedrigere potentielle Energie im Moment der Frakturerzeugung mit 168,0
Joule, gegenüber 185,2 Joule bei Nicht-Flexionsfrakturen.

Schlussfolgerungen Die Hypothese, dass eine als „Flexionsfraktur“ nach
Smith beschriebene Fraktur auch im Rahmen eines Unfalls mit
Extensionsmechanismus entstehen kann, konnte durch die Analyse vorhandener
Frakturpräparate bestätigt werden. Dieser Erkenntnis sollte durch gezielte
biomechanische Untersuchungen mit fokussierter Fragestellung weiter nachgegangen
werden.
Lung ultrasound score for the assessment of lung aeration in ARDS patients: comparison of two approaches
Authors: Mongodi Silvia , Chiumello Davide , Mojoli Francesco
Published: October 2024

Purpose A 4-step lung ultrasound (LUS) score has been previously used to quantify lung density. We compared 2 versions of this scoring system for distinguishing severe from moderate loss of aeration in ARDS: coalescence-based score (cLUS) vs. quantitative-based score (qLUS – >50% pleura occupied by artefacts).

Materials and Methods  We compared qLUS and cLUS to lung density measured by quantitative CT scan in 12 standard thoracic regions. A simplified approach (1 scan per region) was compared to an extensive one (regional score computed as the mean of all relevant intercostal space scores).

Results  We examined 13 conditions in 7 ARDS patients (7 at PEEP 5, 6 at PEEP 15 cmH2O-156 regions, 398 clips). Switching from cLUS to qLUS resulted in a change in interpretation in 117 clips (29.4%, 1-point reduction) and in 41.7% of the regions (64 decreases (range 0.2–1), 1 increase (0.2 points)). Regional qLUS showed very strong correlation with lung density (rs=0.85), higher than cLUS (rs=0.79; p=0.010). The agreement with CT classification in well aerated, poorly aerated, and not aerated tissue was moderate for cLUS (agreement 65.4%; Cohen’s K coefficient 0.475 (95%CI 0.391–0.547); p<0.0001) and substantial for qLUS (agreement 81.4%; Cohen’s K coefficient 0.701 (95%CI 0.653–0.765), p<0.0001). The agreement between single spot and extensive approaches was almost perfect (cLUS: agreement 89.1%, Cohen’s kappa coefficient 0.840 (95%CI 0.811–0.911), p<0.0001; qLUS: agreement 86.5%, Cohen’s kappa coefficient 0.819 (95%CI 0.761–0.848),
p<0.0001).

Conclusion  A LUS score based on the percentage of occupied pleura performs better than a coalescence-based approach for quantifying lung density. A simplified approach performs as well as an extensive one.
Prähospitale Sonografie – eine Evaluation der Anwendung in der Luftrettung
Authors: Rudolph Marcus , Kies Leopold , Braun Joerg , Heinz Wolfgang , Reifferscheid Florian
Published: October 2024

Die Notfallsonografie hat sich als bettseitig durchführbares und schnelles Diagnostikum etabliert, auch in der Präklinik nimmt der Gebrauch dieser Technik zu. Die DRF Luftrettung nutzt diese Technik seit mehr als 20 Jahren. Die vorliegende Arbeit zeigt die Anwendung in der Luftrettung und die Konsequenzen der Untersuchung. Weiterhin werden mögliche Optimierungen aufgezeigt.
Reductive Dehalogenation towards Olefins Mediated by Phase-Transfer Electrocatalysis
Authors: Hiscock Jennifer R. , Clark Ewan R. , Egambaram Orielia P. , Murray Alex T.
Published: October 2024

Mild biphasic conditions enable dibutylviologen salts to act as both phase-transfer catalysts and electrocatalysts for the electroreduction of vicinal dibromides. Optimized experimental reaction conditions permit the production of the corresponding alkenes in competitive yields for a wide range of activated and nonactivated substrates, demonstrating good functional-group tolerance.
Effect of Nucleophile Deprotonation on SuFEx: Synthesis of Sulfonamides
Authors: Barbasiewicz Michał , Dudziński Jan , Bochra Jacek
Published: October 2024

In a quest for efficient SuFEx-type transformations we studied reactions of amines with 4-fluorobenzenesulfonyl fluoride. The substrate may react by fluoride substitution at the aromatic ring (SNAr) and at the sulfonyl group (SuFEx). Analysis of the reaction course revealed that deprotonation of the N-nucleophile controls the reaction course: neutral amines in DMF attack at the aromatic ring, whereas amine anions, generated in equilibrium with LiHMDS in toluene, favor sulfonyl substitution. Using the base-promoted conditions we synthesized a set of substituted sulfonamides in high yields.
Enhanced Synthesis of Sulfonyl Fluorides and Sulfamoyl Fluorides Using Fluorosulfonyl-Containing Radical Reagents
Authors: Weng Jiang , Xiong Ting , Hu Zi-Jun , Wang Ya-Qi
Published: October 2024

Sulfonyl fluorides and sulfamoyl fluorides, as the most significant species among sulfur(VI) fluorides, have garnered considerable attention in various fields, including organic synthesis, materials science, chemical biology, and drug discovery. Fluorosulfonyl-containing radical reagents have unique reactivity and exhibit notable advantages in constructing complex organic molecules, achieving selective functional group transformations. This short review provides a detailed introduction to the diverse applications of fluorosulfonyl-containing radical reagents in organic synthesis, such as C–H bond functionalizations, difunctionalization of olefins, and tandem reactions, highlighting their crucial roles in synthesizing complex organic molecules

1 Introduction

2 Sulfuryl Chlorofluoride (FSO2Cl) as a Radical Reagent for the Synthesis of Sulfonyl Fluorides

3 FABI/IMSF as Solid-State Radical Reagents for the Synthesis of Sulfonyl Fluorides

4 Difunctionalization Reagents for the Synthesis of Bifunctional Sulfonyl Fluorides

5 Fluorosulfonamidation Reagents for the Synthesis of Sulfamoyl Fluorides

6 Conclusion
Applications of Sulfonyl Fluorides in Organic Transformations
Authors: Ke Congyu , Huang Shenlin , Wang Sichang , Zhou Chengxiang , Han Yunzi , Li Miao
Published: October 2024

Sulfonyl fluorides, due to their balanced potential reactivity and stability as well as their compatibility with biological systems, have become important synthetic intermediates and building blocks in the fields of organic synthesis, drug discovery, and materials science. Especially after the report of sulfur(VI) fluoride exchange (SuFEx) chemistry by Sharpless and others, research on sulfonyl fluoride compounds and related compounds has increased significantly. This review summarizes application of sulfonyl fluorides in organic synthesis in the period 2014–2024, discussing different types of organic reactions, including C–X bond formation (including C–C, C–N, and C–F bond formation etc.), S–C bond formation, S–N bond formation, S–O bond formation, multicomponent ‘one-pot’ synthesis, and cyclization.

1 Introduction

2 Sulfonyl Fluorides Applied in C–X (C, N, F) Bond Formation

3 Sulfonyl Fluorides Applied in S–C Bond Formation

4 Sulfonyl Fluorides Applied in S–N Bond Formation

5 Sulfonyl Fluorides Applied in S–O Bond Formation

6 Sulfonyl Fluorides Applied in Multicomponent Reactions

7 Sulfonyl Fluorides Applied in Cyclizations

8 Conclusion and Perspective
Recent Advances in Chlorination: Novel Reagents and Methods from the Last Decade
Authors: Vogel Iago C. , Pinto Diana C. G. A. , Candeias Nuno R.
Published: October 2024

Chlorinated compounds are vital in organic synthesis, impacting nucleophilic substitutions, β-elimination, and C–H acidity. Herein, recent advances in (hetero)arene chlorination, focusing on novel reagents and methods developed in the past decade, are showcased. Traditional electrophilic agents such as Cl2 and PCl5 have been expanded with new chlorinating agents such as Palau’chlor, as well as with electrochemical and photochemical techniques. Biocatalyzed chlorination using FAD-dependent halogenases has also been explored. Key trends include green chemistry with eco-friendly chlorine sources like NaCl and HCl. Although nucleophilic chlorination remains rare, electrochemical methods show promise, despite equipment limitations. This graphical review highlights significant progress in the last decade towards more sustainable and efficient chlorination strategies.
Effectiveness of Dynamic Neuromuscular Stabilization Technique in Neurological Conditions: An Updated Review
Authors: Kaushik Himani , Choudhary Avi , Sharma Mitushi
Published: October 2024

Objective This updated review aims to identify the effectiveness of dynamic neuromuscular stabilization (DNS) techniques in neurological conditions.

Method A literature search was carried out from 2013 to 2024 on PubMed, Google Scholar, Research Gate, and Scopus databases. Following keywords were used to identify the relevant articles such as dynamic neuromuscular stabilization, reflex-mediated DNS, neurological conditions, DNS, cerebral palsy, stroke, Parkinson's disease, multiple sclerosis, neurodegenerative conditions, ataxia, Alzheimer's disease, and multiple sclerosis with Boolean operators. All the full-text, English-written articles based on inclusion and exclusion criteria were included in the review irrespective of their experiment study design, only the review article was excluded.

Results This updated review included 10 articles related to neurological conditions including, stroke, multiple sclerosis, Alzheimer's disease, Parkinson's disease, and cerebral palsy. The results show significant differences in various outcome measures of the included studies.

Conclusion The findings suggest that DNS is an effective approach to use in the rehabilitation protocol of neurologically impaired patients and is beneficial in improving their health outcomes and overall quality of life. This review concludes that more evidence is required in this area of research with good quality research and long follow-up periods.
A Practical Approach to Diagnosing Peripheral Neuropathies
Authors: Jacoby Nuri , Anziska Yaacov
Published: October 2024

Polyneuropathies are common, with the incidence increasing with older age. The causes of polyneuropathies are diverse and numerous, and it can be challenging for clinicians to determine the etiology of a particular patient's neuropathy. In this article, we systematically detail a practical approach to polyneuropathies, beginning with the most important aspects of the workup, the history and physical. We then discuss the limited diagnostic approach required for patients who present with a distal symmetric polyneuropathy and the more comprehensive approach for patients who present with other neuropathy subtypes.
The Evolving Landscape of Small Fiber Neuropathy
Authors: Devigili Grazia , Lombardi Raffaella , Lauria Giuseppe , Cazzato Daniele
Published: October 2024

Small fiber neuropathy (SFN) belongs to a heterogeneous group of disorders in which thinly myelinated Aδ and unmyelinated C-fibers are primarily affected, leading to neuropathic pain and autonomic symptoms. SFN can be associated with systemic conditions such as diabetes, autoimmune diseases, exposure to drugs and toxins, and infection, with the list of associated diseases continuing to expand. Variants in the SCN9A, SCN10A, and SCN11A genes encoding Nav 1.7, Nav 1.8, and Nav 1.9 sodium channel subunits, as well as in the TRPA1 gene, have been found in SFN patients, expanding the spectrum of underlying conditions and enhancing our understanding of pathophysiological mechanisms. There is also growing interest in immune-mediated forms that could help identify potentially treatable subgroups. According to international criteria, diagnosis is established through clinical examination, the assessment of intraepidermal nerve fiber density, and/or quantitative sensory testing. Autonomic functional tests allow for a better characterization of dysautonomia in SFN, which can be subclinical. Other tests can support the diagnosis. Currently, the management of SFN prioritizes treating the underlying condition, if identified, within a multidisciplinary approach that combines symptomatic pain therapy, lifestyle changes, and biopsychological interventions. Emerging insights from the molecular characterization of SFN channelopathies hold promise for improving diagnosis, potentially leading to the discovery of new drugs and refining trial designs in the future. This article reviews the clinical presentation, diagnostic workup, and advancing knowledge of associated conditions and interventional management of SFN.
Locoregional Therapies and Interventional Radiology in Managing Hepatocellular Carcinoma: A Comprehensive Approach to Bridging, Downstaging, and Liver Transplantation
Authors: Barrera Juana V. , Dallag Leonard , Akram Rubeel , Salsamendi Jason , Barragan Camilo , Wehrle Chase J. , Benjamin Jamaal , Molano Maria del Pilar Bayona
Published: October 2024

Hepatocellular carcinoma (HCC) remains a significant global health challenge, particularly for patients awaiting liver transplants (LTs) due to the scarcity of donor organs. During the waiting period, a multidisciplinary approach becomes crucial to optimize tumor treatment and preserve liver function. In recent years, interventional radiology has emerged as an integral part of treatment strategies. It has played a pivotal role in bridging and downstaging patients on the path to transplantation. Interventional radiologists administer minimally invasive locoregional therapies to HCC patients on LT waiting lists. Additionally, they address complications such as portal hypertension and portal vein thrombosis, which can lead to clinical deterioration and jeopardize transplant candidacy. This article examines the pivotal role of interventional radiology in the management of HCC, highlighting recent studies and advancements within the field. Additionally, it provides a concise review of the eligibility criteria for LT in patients with HCC, alongside a discussion of the surgical techniques employed in LT for these patients.
Hysteresis compensation and decoupling control of an XYΘ-type flexure-based mechanism via inverse hysteresis-coupling hybrid modeling
Authors: Qin Yanding , Yuan Jie , Zhang Yunpeng , Tang Hui , Han Jianda
Published: October 2024

Planar positioning systems are widely utilized in micro and nano applications. The challenges in modeling and control of XYΘ flexure-based mechanisms include hysteresis of the piezoelectric actuators, couplings among the input axes, and coupled linear and angular motions of the end effector. This paper presents an inverse hysteresis-coupling hybrid model to account for such hysteresis and couplings. First, a specially designed kinematic chain is adopted to transfer the pose of the end effector into the linear motions at three prismatic joints. Second, an inverse hysteresis-coupling hybrid model is developed to linearize and decouple the system via a multilayer feedforward neural network. A fractional-order PID controller is also integrated to improve the motion accuracy of the overall system. Experimental results demonstrate that the proposed method can accurately control the motion of the end effector with improved accuracy and robustness.
On higher deformed Calogero–Sutherland Hamiltonians
Authors: Zhang Fu-Hao , Liu Fan , Li Yue , Zhang Chun-Hong
Published: October 2024

In terms of the nested commutators, we present the higher deformed Calogero–Sutherland Hamiltonians. Based on these higher Hamiltonians, we construct the partition functions through W-representations and present the character expansions. Furthermore, we construct the extended operators of deformed Calogero–Sutherland model and give the eigenfunctions.
2D layered halide perovskite for field-effect transistors
Authors: Paul Tufan , Colella Silvia , Orgiu Emanuele
Published: October 2024

Field-effect transistors are crucial components for modern electronics, generating significant research and profitable interest. Metal halide perovskites have recently emerged as a pioneering active material in solar cells, generating interest in their potential use in other electronic and (opto)electronic devices, including field-effect transistors and phototransistors. However, before they can be commercialized, they still face significant challenges owing to their immanent instabilities with respect to heat, moisture, and light. In contrast, due to their exceptional environmental stability, the newly emerging two-dimensional Ruddlesden–Popper type perovskites have garnered significant recognition. The current state of the field is covered in this review article, as are the problems, and a perspective for the scenarios of perovskite field-effect transistors. The effects of temperature, light, and measurement conditions are taken into account, as well as the physics of the device and the fundamental mechanisms that drive these devices, such as ion migration and ionic defects. Subsequently, the performance of perovskite transistors and phototransistors described so far is analyzed and critically evaluated. Finally, the major roadblocks to perovskite transistor advancement are identified and explored. The lessons learned from other perovskite optoelectronic devices are investigated in order to address these obstacles and bring these devices closer to industrial implementation.
Bulk proton conduction in films from a truncated reflectin variant
Authors: Pratakshya Preeta , Kwansa Albert L. , Kovačič Matic , Kaimal Nikhil , Panteleev Arsenii , Chatterjee Atrouli , Tolouei Nadia E. , Kautz Rylan , Naughton Kyle L. , Sartori Barbara , Marmiroli Benedetta , Dao MyAnh K. , Bernstorff Sigrid , Plavec Janez , Yingling Yaroslava G. , Gorodetsky Alon A.
Published: October 2024

Protein- and peptide-based proton-conducting biomaterials have been touted as particularly promising for bioelectronics applications because of their advantageous chemical and physical characteristics, typically excellent biocompatibilities, and readily understood electrical properties. Within this context, our laboratory has previously discovered and systematically investigated bulk proton conduction for a unique family of cephalopod structural proteins called reflectins. Herein, we leverage a combination of experimental and computational methodologies to investigate the bulk electrical properties of hierarchically nanostructured films self-assembled from a previously reported truncated reflectin variant. Our findings indicate that the truncated reflectin variant exhibits protonic conductivities and associated figures of merit on par with those reported for both full-length reflectins and other proteinaceous proton-conducting materials. The combined studies enhance current understanding of reflectins’ functional properties within the framework of bioengineering and bioelectronics applications and may ultimately facilitate the development of other protein- and peptide-based conductive biomaterials.
Analysis and control of Hall effect thruster using optical emission spectroscopy and artificial neural network
Authors: Ben Slimane Tarek , Leduc Alexandre , Schiesko Loïc , Bourdon Anne , Chabert Pascal
Published: October 2024

This study presents a proof-of-principle for using optical emission spectroscopy and artificial neural networks for real-time monitoring and control of the operational parameters of a Hall effect thruster: the anode voltage, the anode xenon injection, the discharge current, and the coil current. In that regard, we build an optical database of 26 spectral lines across 6469 operating conditions to train and test the neural network. We then reduced the learning lines from 26 to 15 based on their statistical correlation with the target parameters. After tuning the hyperparameters of the network, the network predicted the thruster’s parameters with notable accuracies: 95% for the anode voltage, 84% for the coil current, and 99% for both the anode flow rate and the discharge current. The estimated uncertainty of predictions, at 3σ, is ±51V for voltage, ±1A for coil current, ±0.15A for discharge current, and ±0.15mgs−1 for anode flow rate. The prediction calculations were within milliseconds and enabled real-time monitoring of the thruster parameters. Therefore, a proportional-integrator-derivative controller (PID) controller was implemented to regulate the anode voltage and flow rate based on the optical emission of the plume. The PID showcased short settling times from 0.1 to 0.4 s and overshoot levels up to 3% of the target value for the voltage and 10% of the target value for the flow rate. These results were for a fixed coil current at 4A. The study showed that changing the coil current may necessitate more sophisticated prediction models and control strategies. Future work will expand the model’s generalizability to different thruster types, propellants, and magnetic field configurations.
Frequency linearization of voltage controlled oscillator (VCO) for 2 µs frequency modulated continuous wave (FMCW) reflectometer
Authors: Seo Seong-Heon
Published: October 2024

Frequency modulated continuous wave reflectometers have been widely used to measure plasma density profiles in many magnetic fusion devices. The frequency modulation (FM) time of the KSTAR reflectometer was 20 µs, that is, the FM rate was 50 kHz. However, the edge density of the KSTAR tokamak fluctuates typically over the frequency range of 20–50 kHz in the ELMy H-mode plasmas. Therefore, the density profile changes significantly during the FM time, causing significant distortion in the density profile measurements. The FM rate must be increased at least ten times faster than the density fluctuation frequency. A new voltage controlled oscillator (VCO) driver is designed based on the AD8067 operational amplifier to achieve a FM time of 2 µs. The VCO output frequency is linearly modulated by predistorting the tuning voltage of VCO using a 400 MSamples/s arbitrary waveform generator. The resulting output frequency of the VCO is measured by mixing the VCO output with a fixed frequency synthesizer signal and measuring the mixer intermediate frequency using a 2.5 GSamples/s digitizer. The tuning voltage is adjusted to minimize the amount by which the measured frequency deviates from the linearly modulated frequency. A simple linear adjustment proportional to the deviation does not effectively suppress the nonlinearity in FM. The response time of the VCO driver and the VCO input interface should be taken into account by solving the entire circuit equation. In this paper, the developed VCO driver circuit and the frequency linearization method are described.
Structural stability of transonic shocks for the full compressible Euler system in a two-dimensional general nozzle with an external force
Authors: Yang Wengang
Published: October 2024

In this paper, we investigate the transonic shock solutions to the full compressible Euler system in a general two-dimensional nozzle with an external force. In their book, Courant and Friedrichs [Supersonic Flow and Shock Waves (Interscience Publishers, Inc., New York, 1948)] described the transonic shock phenomena in a de Laval nozzle: given the appropriate receiver pressure, if the upcoming flow is still supersonic after passing through the throat of the nozzle, then a shock front intervenes at some place in the diverging part of the nozzle, and the gas is compressed and slowed down to subsonic speed. We first establish the existence and uniqueness of one-dimensional transonic shock solutions to the steady full Euler system with an external force by prescribing suitable pressure at the exit of the nozzle when the upstream flow is a uniform supersonic flow. With the help of external forces, both existence and uniqueness are established by solving a nonlinear free boundary value problem in a weighted Hölder space.
Controlling and optimizing the transport (search) efficiency with local information on a class of scale-free trees
Authors: Gao Long , Peng Junhao , Tang Chunming , Xu Qiuxia
Published: October 2024

The scale-free trees are fundamental dynamics networks with extensive applications in material and engineering fields owing to their high reliability and low power consumption characteristics. Controlling and optimizing transport (search) efficiency on scale-free trees has attracted much attention. In this paper, we first introduce degree-dependent weighted tree by assigning each edge (x,y) a weight wxy=(dxdy)θ, with dx and dy being the degree of nodes x and y, and θ being a controllable parameter. Then, we design a parameterized biased random walk strategy with the transition probability depending on the local information (the degree of neighboring nodes) and a parameter θ. Finally, we evaluate analytically the global mean first-passage time, which is an important indicator for measuring the transport (search) efficiency on the underlying networks, and find the interval for parameter θ where transport (search) efficiency can be improved on a class of scale-free trees. We also analyze the (transfinite) walk dimension for our biased random walk on the scale-free trees and find one can obtain arbitrary transfinite walk dimension in an interval by properly tuning the biased parameter θ. The results obtained here would shed light on controlling and optimizing transport (search) efficiency on objects with scale-free tree structures.
ATP-induced reconfiguration of the micro-viscoelasticity of cardiac and skeletal myosin solutions
Authors: Domínguez-García Pablo , Pinto Jose R. , Akrap Ana , Jeney Sylvia
Published: October 2024

We study the high-frequency, micro-mechanical response of suspensions composed of cardiac and skeletal muscle myosin by optical trapping interferometry. We observe that in low ionic strength solutions, upon the addition of magnesium adenosine triphosphate (MgATP2−), myosin suspensions radically change their micro-mechanics properties, generating a viscoelastic fluid characterized by a complex modulus similar to a suspension of worm-like micelles. This transduction of energy, from chemical to mechanical, may be related to the relaxed states of myosin, which regulate muscle contractility and can be involved in the etiology of many myopathies. Within an analogous generic mechanical response, cardiac and skeletal myosin suspensions provide different stress relaxation times, elastic modulus values, and characteristic lengths. These discrepancies probably rely on the dissimilar physiological functions of cardiac and skeletal muscle, on the different MgATPase hydrolysis rates of cardiac and skeletal myosins, and on the observed distinct cooperative behavior of their myosin heads in the super-relaxed state. In vitro studies like these allow us to understand the foundations of muscle cell mechanics on the micro-scale, and may contribute to the engineering of biological materials whose micro-mechanics can be activated by energy regulators.
Generation of partially coherent full Poincaré beam arrays and their Stokes scintillations in turbulent media
Authors: Wang Yakun , Gu Kexin , Dong Zhen , Wang Fei , Chen Yahong , Cai Yangjian , Liu Yonglei
Published: October 2024

A type of vector beam arrays, called partially coherent full Poincaré (PCFP) beam arrays, is introduced and experimentally synthesized using modal-vector-decomposition method. Our experimental system involves a digital micro-mirror device, which can generate such beam arrays with controllable spatial coherence and array structure in almost real-time, enabling to test the impact of atmospheric turbulence on them. Furthermore, we experimentally examine the scintillations of four Stokes parameters (denoted as S0, S1, S2, and S3) of PCFP beam arrays propagating through lab-simulated turbulence. The results indicate that the Stokes scintillations decrease as the number of beamlets increase or spatial coherence decreases. In contrast to S0 scintillation (intensity scintillation), S1, S2, or S3 scintillation is less affected by the turbulence under the same conditions. Our experimental results show that S2 and S3 scintillations could reduce by 67.2% and 52.4% compared to the intensity scintillation in strong turbulence. Our findings have potential applications in free-space optical communication when the Stokes parameter S2 or S3 is served as an information carrier.
Enhanced optical nonlinearity in suspensions of dual-resonance gold–copper chalcogenide core–shell nanoparticles
Authors: Ning Dongling , Lin Xinyu , Ren Yu-Xuan , Liang Yi , Lin Tao
Published: October 2024

Plasmonic copper chalcogenide (Cu2−xE, E = S, Se, Te) nanoparticles (NPs) possess high potentials in photothermal therapy and photoacoustic tomography for their unique localized surface plasmon resonant absorption in the second near-infrared biologically transparent window. In this study, strong thermal-induced nonlinear negative-lens effect in aqueous suspensions containing Cu2−xSe NPs was observed. Furthermore, the nonlinear absorption was notably enhanced in aqueous suspensions containing Au@Cu2−xSe core–shell NPs, as the positive nonlinear absorption coefficient increased by 20-fold, attributed to the strong plasmonic coupling in Au@Cu2−xSe core–shell NPs. This finding underscores the importance of the nonlinear optical behaviors of plasmonic NPs in biomedical applications, as they offer extra strategy for optimizing systems and incorporating additional functionalities.
Shortest path counting in complex networks based on powers of the adjacency matrix
Authors: Tan Dingrong , Deng Ye , Xiao Yu , Wu Jun
Published: October 2024

Complex networks describe a broad range of systems in nature and society. As a fundamental concept of graph theory, the path connecting nodes and edges plays a crucial role in network science, where the computation of shortest path lengths and numbers has garnered substantial focus. It is well known that powers of the adjacency matrix can calculate the number of walks, specifying their corresponding lengths. However, developing methodologies to quantify both the number and length of shortest paths through the adjacency matrix remains a challenge. Here, we extend powers of the adjacency matrix from walks to shortest paths. We address the all-pairs shortest path count problem and propose a fast algorithm based on powers of the adjacency matrix that counts both the number and the length of all shortest paths. Numerous experiments on synthetic and real-world networks demonstrate that our algorithm is significantly faster than the classical algorithms across various network types and sizes. Moreover, we verified that the time complexity of our proposed algorithm significantly surpasses that of the current state-of-the-art algorithms. The superior property of the algorithm allows for rapid calculation of all shortest paths within large-scale networks, offering significant potential applications in traffic flow optimization and social network analysis.
Using an electrically charged mist to visualize the potential wells in “sonomaglev,” a combined diamagnetic-acoustic levitator
Authors: Hunter-Brown George , Sampara Naresh , Scase Matthew M. , Hill Richard J. A.
Published: October 2024

We use a water mist to experimentally visualize the wells in the potential energy of material levitated by a combined diamagnetic-acoustic levitator. The levitator consists of an 18.5 T superconducting magnet, which can levitate diamagnetic material, such as water, plastics, and organic materials, by applying a magnetic body force counteracting the force of gravity. Low-power ultrasound transducers operated at 37.5 kHz generate an acoustic field that spatially modulates the net force acting on the diamagnetically levitated material, making “sonomaglev” capable of levitating multiple objects in stable equilibrium. In these experiments, we levitate a mist of water droplets that are electrically charged so that they repel each other, preventing them from coalescing as a single drop in each of the local potential minima. The shapes of the potential wells are revealed by the shapes of clusters of droplets, which conform to the isosurfaces of the sum of the magnetic, gravitational, and acoustic potentials. The spacing of the droplets in a cluster is shown to depend on their charge, volume, and the force constant of the well in a simple model. Compared to acoustic levitation alone, the combination of diamagnetic and acoustic levitation allows more scope for the manipulation of levitated objects, since the acoustic field is not constrained by the requirement to balance the force of gravity. The method demonstrated here allows the influence on the potential energy of switching on the acoustic field to be observed directly.
On the propagation of dynamical waves in complex cometary plasma environments with thermal heavy ions and non-extensive light species
Authors: Abdelwahed H. G. , Mahmoud Abeer A.
Published: October 2024

A variety of dust acoustic (DA) waves like solitons, shock waves, and double-layer structures can generate and propagate in dusty plasma systems depending on the plasma composition and their particle distributions. In this paper, a refined fluid model is proposed to provide a general description of all possible DA waves that may propagate in complex dusty plasmas with thermally distributed heavy ions and non-extensive light species. The DA waves are characterized using the Further-Burger equation with three newly induced arbitrary parameters, enabling the identification of the different plasma waves. The DA wave's structures are found to be highly sensitive to the thermal parameter σ of the heavy ions and the non-extensive parameter “q” of the light species. Moreover, these two parameters act as key factors that control the polarity of the waves around their critical values, i.e., around σ  = 0.11 and “q = 1.146.” The potential relevance of our results in space and astrophysics plasma setups is briefly discussed.
Multi-function vortex array radar
Authors: Li Xiaofei , Bashiri Sajjad , Ponomarenko Vasilisa , Wang Yu , Cai Yangjian , Ponomarenko Sergey A.
Published: October 2024

In the realm of automation systems, multi-function radars serve as essential sensory components for self-driving vehicles and airbornes. Effective resource allocation management is crucial, requiring a high level of versatility to accomplish multiple tasks, especially, for increasingly miniaturized hardware. Here, we advance a balanced protocol for detecting, positioning, and tracking moving targets in real-time. Our protocol integrates efficient data processing methods with robust hardware. Specifically, detection signals are modulated by optical vortices for imaging, and real time processing of the image field facilitates target positioning and tracking. Moreover, the protocol extends its utility to serve as a topographic laser profiling system for natural landscapes, highlighting its adaptability. This adaptability and versatility well position the proposed protocol to support a wide range of applications, spanning self-driving vehicles and aerial systems, underscoring its potential significance across multiple platforms.
Optical and electrical degradation behavior of GaN-based UV-A laser diodes
Authors: Huang Yujie , Yang Jing , Zhao Degang , Liu Zongshun , Liang Feng , Chen Ping
Published: October 2024

The degradation mechanism of GaN-based ultraviolet (UV-A) laser diodes (LDs) is analyzed by studying the changes of their electrical and optical properties after aging process with the operation current below the threshold current (Ith). After aging treatment, Ith increases, the slope efficiency decreases, and the leakage current increases. In particular, the emission spectra of aged LD show significant broadening, with additional peaks on the shorter wavelength side. Both cathodoluminescence and deep level transient spectrum results indicate defects can develop around the active region of the LD, even when the operation current is below Ith. This leads to an increase in trap-assisted tunneling current and non-radiative recombination. The observed defects may result from the diffusion of water molecule in the environment from the cavity facet into the active region and formation of ON–CN and VGaON complex defects. These defects not only reduce the effective carrier concentration injected into the quantum well but also increase non-radiative recombination. These results will contribute to our understanding of the degradation mechanism of UV LDs and the preparation of long lifetime UV LDs.
Impact of liquid crossflow on the discharge coefficient of a gas jet hole on a flat plate
Authors: Wang Wenjun , Wang Guilin , Hou Dongbo , Lu Jiaxing , Wei Yingjie
Published: October 2024

This study combines the experimental and numerical simulation methods to deeply analyze the impact of liquid crossflow on the discharge coefficient of a gas jet hole on a flat plate. Experiments were conducted to examine the influence of momentum flux ratio and theoretical momentum flux ratio on the discharge coefficient under various crossflow Reynolds numbers. It was found that the variation of the discharge coefficient with the theoretical momentum flux ratio clearly reflects the impact of the crossflow boundary layer velocity profile on the discharge coefficient. The rapid growth of velocity in the boundary layer near the wall in the direction normal to the wall surface, or the decrease in the thickness of the boundary layer, both enhance the shearing effect of the crossflow, leading to a decrease in the discharge coefficient. Analysis of the cavity morphology at the hole exit captured by high-speed camera revealed that the averaged profile of the gas–liquid boundary on the symmetrical plane of the jet below the hole can be approximated as a straight line within the scale of the hole diameter, and the sine of the angle between this line and the upper wall surface is roughly equivalent to the normalized discharge coefficient. This relationship was physically interpreted through the analysis of effective and equivalent flow cross-sectional shapes derived from numerical simulation at different crossflow Reynolds numbers and theoretical momentum flux ratios. Additionally, this paper introduces an innovative method for predicting jet flow rate based on image processing technology. A notable feature of this method is that it does not require the measurement of the pressure inside the gas chamber.
Boltzmann optical thermometry for cryogenics
Authors: Zeman Marek , Camus Philippe , Chanelière Thierry
Published: October 2024

We propose and implement an optical technique to access the local temperature of an erbium doped crystal by probing the electron spin population under magnetic field. We reliably extract the sample temperature in the range 2–7 K. We additionally discuss the suitability of our method as a primary standard for cryogenic thermometry. By adding an auxiliary heating laser, we are able to measure the interface conductance between the dielectric crystal and the cold plate of the cryostat by exploring different cooling configurations.
Broadband and widely tunable second harmonic generation in suspended thin-film LiNbO3 rib waveguides
Authors: Zinaoui Aiman , Grosjean Lucas , De Sousa Lopes Moreira Arthur , Suarez Miguel Angel , Queste Samuel , Robert Laurent , Gauthier-Manuel Ludovic , Chauvet Mathieu , Courjal Nadège
Published: October 2024

Our study demonstrates second harmonic generation (SHG) in a high confinement LiNbO3 rib waveguide through type-I birefringence phase matching of fundamental modes. The combination of micro-waveguide dispersion and material birefringence reveals unique SHG characteristics that complement the performance of standard LiNbO3 on insulator (LNOI) components. Dual-pump wavelength phase matching in the near-infrared and mid-infrared regions is shown in a given waveguide. These two wavelengths can be positioned in the 1.1–3.5 μm range or converge near 1.5 μm by adjusting the core waveguide size or through temperature tuning. A 25 °C temperature change enables a broad pump tunability band of 300 nm, ranging from 1350 to 1650 nm, with a conversion efficiency exceeding 40 %/W/cm2 within a single waveguide. A temperature tuning range of up to 900 nm is foreseen by tailoring the waveguide core size. In addition, a broadband response of 150 nm within the telecom window is demonstrated experimentally. The nonlinear waveguide, etched in a thin film membrane, is combined with titanium-indiffused waveguides to form a monolithic LiNbO3 component. This configuration provides low coupling losses of 0.8 dB and single-mode operation. It paves the way for a new generation of versatile and cost-effective frequency conversion components with wide-band spectral responses suitable for optical communications, environmental sensing, and quantum information processing.
Application of conductive graphene films for high-performance hemispherical resonator gyroscopes
Authors: Wang Fei , Wang Jian , Yi Zhuqing , Ye Chuanren , Zhu Yanwu
Published: October 2024

Hemispherical resonator gyroscope is a type of solid-state gyroscope, in which the fused silica hemispherical resonator with a high-quality factor (Q factor) is the key for the fabrication of high-performance devices. However, the metal film coated on the silica as the electrode for trigging the resonance often leads to the largely deteriorated Q factor. In this work, high-quality graphene films with controllable number of layers are uniformly coated on silica utilizing C2H4 as precursor in chemical vapor deposition. Replacing the metal film as the electrode, the hemispherical resonator coated with graphene demonstrates a Q factor of 3.38 × 106, with a high retention of 77.17%. At an optimized preparation temperature of 1130 °C, the graphene film shows a good adhesion with the silica hemisphere, providing an excellent candidate as the electrode for high-performance hemispherical resonators.