bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on drying performance of high voltage cable buffer layer material
Authors: Zhang Jing , Liu Jinghua , Luo Chuanxian , He Liang , Cheng Lifeng , Cai Yuru
Published: March 2022

In order to study the failure mechanism of high-voltage cable buffer layer caused by moisture and the performance of the material after immersion and drying, according to the structure and size of 110 kV XLPE cable, the requirements for the separation distance between corrugated aluminum sheath and insulating outer shield before and after the change of buffer layer resistivity caused by moisture were calculated, the influence of moisture on ablation failure was analyzed. The test platform of buffer layer material was built, the properties of two kinds of materials without water immersion and after water immersion drying were tested, including semi-conductive buffer water-blocking tape and semi-conductive buffer tape. The results show that when the moisture content was large, the resistivity of the buffer layer increases, which reduces the requirements of the allowable separation distance of the cable, and was more likely to cause the discharge and ablation of the buffer layer. The water in the buffer layer was removed by drying at 70 °C, with thickness, weight, the water content, elongation at break, breaking strength and volume resistivity can be recovered, which verifies that the heating drying method is feasible for the removal of water from the buffer layer.
Research on application of “double-carbon power index” system based on delphi method
Authors: Wang Jiayu , Ding Han , Hu Xiao , Hua Liang , Xu Zhongping , Zhang Chengping , Hu Dongliang
Published: March 2022

Double carbon-power index is an important index to measure regional carbon dioxide emission, regional economic development and carbon emission reduction implementation.It can determine whether carbon dioxide has reached a peak in a region or industry, so that the government can take targeted measures to guide enterprises to reduce carbon dioxide.Through build wuxi double carbon power index system, based on the Delphi method to carry out the comprehensive evaluation, explore their short-term carbon emissions to peak, the path of the development of long-term carbon neutral, assist the government in a timely manner to master carbon, carbon reduction status, so as to promote comprehensive ground application carbon reduction measures, for zero carbon high quality under the restriction of power in wuxi city development.
Application of flexible colloid-fiber compound plugging technology in oil and gas wells with large differential pressure in the East China Sea
Authors: Li Sanxi , Niu Chengcheng , Zhang Yufei , Ge Junrui , He Wei
Published: March 2022

In order to solve the contradiction between the safety requirements of well control in the upper reservoir and the loss of kill fluid in the lower reservoir, the idea of “compound plugging technology” was proposed to solve the abnormal pressure inversion phenomenon of “the co-existence of blowout and lost circulation” with large interlayer pressure difference. Flexible colloidal particle-fiber composite temporary plugging fluid was developed. The plugging layer formed by the temporary plugging fluid of flexible rubber fiber can withstand the positive pressure difference of more than 40 MPa, and there is no overflow and leakage. The advantages of compound temporary plugging fluid under large differential pressure are verified and it has a good application prospect.
Numerical solution of the mix quantum rabi model
Authors: Xia Yifei
Published: March 2022

The mixed quantum rabi model is generated based on the interaction of single photon and two photon. Based on the mix QRM under one-qubit, this paper extended it to two-qubit Hamiltonian and solve it, then analyzed the variation law of different parameter variables and the symmetry of matrix.
Individualized feedback on colonoscopy skills improves group colonoscopy quality in providers with lower adenoma detection rates
Authors: Keswani Rajesh N. , Wood Mariah , Benson Mark , Gawron Andrew J. , Kahi Charles , Kaltenbach Tonya , Yadlapati Rena , Gregory Dyanna , Duloy Anna
Published: March 2022

Background and study aims Colonoscopy inspection quality (CIQ) assesses skills (fold examination, cleaning, and luminal distension) during inspection for polyps and correlates with adenoma detection rate (ADR) and serrated detection rate (SDR). We aimed to determine whether providing individualized CIQ feedback with instructional videos improves quality metrics performance.

Methods We prospectively studied 16 colonoscopists who already received semiannual benchmarked reports of quality metrics (ADR, SDR, and withdrawal time [WT]). We randomly selected seven colonoscopies/colonoscopist for evaluation. Six gastroenterologists graded CIQ using an established scale. We created instructional videos demonstrating optimal and poor inspection techniques. Colonoscopists received the instructional videos and benchmarked CIQ performance. We compared ADR, SDR, and WT in the 12 months preceding (“baseline”) and following CIQ feedback. Colonoscopists were stratified by baseline ADR into lower (≤ 34 %) and higher-performing (> 34 %) groups.

Results Baseline ADR was 38.5 % (range 26.8 %–53.8 %) and SDR was 11.2 % (2.8 %–24.3 %). The proportion of colonoscopies performed by lower-performing colonoscopists was unchanged from baseline to post-CIQ feedback. All colonoscopists reviewed their CIQ report cards. Post-feedback, ADR (40.1 % vs 38.5 %, P = 0.1) and SDR (12.2 % vs. 11.2 %, P = 0.1) did not significantly improve; WT significantly increased (11.4 vs 12.4 min, P < 0.01). Among the eight lower-performing colonoscopists, group ADR (31.1 % vs 34.3 %, P = 0.02) and SDR (7.2 % vs 9.1 %, P = 0.02) significantly increased post-feedback. In higher-performing colonoscopists, ADR and SDR did not change.

Conclusions CIQ feedback modestly improves ADR and SDR among colonoscopists with lower baseline ADR but has no effect on higher-performing colonoscopists. Individualized feedback on colonoscopy skills could be used to improve polyp detection by lower-performing colonoscopists.
Postoperatives Monitoring freier Muskellappenplastiken mittels perforatorbasierten adipokutanen Monitorinseln: Ökonomie, Versorgungsqualität und Ästhetik
Authors: Nagel Sarah Sopie , Thomas Benjamin , Bigdeli Amir K. , Hirche Christoph , Kneser Ulrich , Radu Christian Andreas
Published: March 2022

Hintergrund Freie Muskellappenplastiken zur Rekonstruktion großer Weichteildefekte sind neben fasziokutanen Lappenplastiken etablierte mikrochirurgische Standardverfahren. Diese werden häufig mit adipokutanen Monitorinseln zur Durchblutungskontrolle geplant. In unserer Klinik werden sowohl konventionelle, breitbasig aufsitzende adipokutane Monitorinseln (random pattern), als auch perforatorbasierte Monitorinseln verwendet. Während konventionelle Monitorinseln in einer zweiten Operation abgetragen werden müssen und der verbliebene Defekt mit Spalthauttransplantaten versorgt werden muss, können perforatorbasierte Monitorinseln am Patientenbett mittels einfacher Ligatur entfernt werden. In der vorliegenden Studie sollen ökonomische, versorgungsqualitative und ästhetische Aspekte perforatorbasierter versus herkömmlicher adipokutaner Monitorinseln nach freiem Muskellappentransfer verglichen werden.

Patienten und Methoden Im Zeitraum von August 2014 bis Juli 2016 konnten anhand einer retrospektiven Datenanalyse 102 geeignete Patienten identifiziert werden. Patienten mit perforatorbasierter Monitorinsel (Gruppe A) wurden einem Kollektiv von Patienten mit breitbasig aufsitzender Monitorinsel (Gruppe B) gegenübergestellt. Patientencharakteristika, Operationszeiten, ökonomische Daten und ästhetische Ergebnisse wurden zwischen den Gruppen verglichen.

Ergebnisse Bei 72 Patienten wurden perforatorbasierte (Gruppe A, 71 %), bei 30 Patienten konventionelle (Gruppe B, 29 %) Monitorinseln gehoben. Patienten-, Defekt- und Lappencharakteristika waren in beiden Gruppen vergleichbar. Operations- und Säulenzeit waren in Gruppe B tendenziell kürzer, jedoch ohne statistische Signifikanz zu erreichen (p = 0,35; p = 0,28). Die Entfernung der Monitorinsel in Gruppe A erfolgte signifikant früher (p < 0,01). Sowohl die gesamtstationäre als auch die postrekonstruktive Verweildauer waren in Gruppe A signifikant kürzer (p = 0,03; p < 0,01). Personelle und materielle Ressourcen konnten in Gruppe A geschont und ein ästhetisch ansprechenderes Ergebnis erzielt werden.

Schlussfolgerung Mit perforatorbasierten Monitorinseln kann eine zweite Operation zur Monitorinselabtragung und Hauttransplantation vermieden werden. Hierdurch kann eine Reduktion der stationären Verweildauern mit Schonung der materiellen und personellen Ressourcen erreicht werden.
Kontrastmittelinduziertes Nierenversagen
Authors: Gohlisch Christopher
Published: March 2022

Ein akutes Nierenschädigungsereignis bedeutet für Patienten ein erhöhtes Mortalitätsrisiko, Morbiditätsrisiko sowie ein erhöhtes Risiko für eine chronische Nierenerkrankung. Daher stellt sich im klinischen Alltag stets die Frage, wie eine akute Nierenschädigung nicht nur behandelt, sondern v. a. auch präventiv vermieden werden kann. In erster Linie gilt es, Patienten durch diagnostische und therapeutische Maßnahmen nicht mehr zu schaden als zu helfen. Die wahrscheinlich am häufigsten genutzte Diagnostik im medizinischen Alltag stellt sicher die Bildgebung und die damit häufig verbundene Gabe von Kontrastmittel (KM) dar, dessen Einfluss auf die Nierenfunktion durchaus kontrovers ist. Dieser Artikel gibt einen Überblick über die aktuelle Datenlage und den wissenschaftlichen Diskurs bzgl. des kontrastmittelinduzierten Nierenversagens (KIN).
PET-CT-Diagnostik in der Nephrologie für nichtonkologische Indikationen
Authors: Babic Milen , van der Giet Markus
Published: March 2022

Die PET-CT kombiniert ein nuklearmedizinisches Verfahren (PET: Positronen-Emissions-Tomografie) mit einem topografischen, bildgebenden Verfahren (CT: Computertomografie), um stoffwechselaktive Prozesse darstellen zu können und diese möglichst präzise anatomischen Strukturen zuzuordnen. Die PET-CT-Diagnostik hat mittlerweile vor allem für onkologische Indikationen einen festen Stellenwert. Darüber hinaus gibt es einige interessante Anwendungen in der Differenzialdiagnostik bzw. Diagnosesicherung bei renalen Fragestellungen nichtonkologischer Erkrankungen. In der vorliegenden Übersicht werden einige Beispiele genannt, bei welchen die PET-CT-Diagnostik sehr hilfreich sein kann, um eine renale Krankheit besser zu charakterisieren oder deren Lokalisation zu spezifizieren.
Ältere Patienten in der Psychosomatischen Klinik – Gesundheit, Bindung und Mentalisierung
Authors: Peters Meinolf
Published: March 2022

Bislang ist wenig bekannt über ältere Menschen, die in Psychosomatischen Kliniken behandelt werden, obwohl die Behandlungszahlen dieser Altersgruppe zunehmen. In der hier vorgestellten Untersuchung wurde eine Stichprobe über 60jähriger Patienten dreier Psychosomatischer Kliniken (N=83) und eine Stichprobe klinisch nicht auffälliger Probanden (N=89) gleichen Alters untersucht. Neben gesundheitlichen Variablen, in denen sich die älteren Patienten von den klinisch nicht-auffälligen Probanden sowie von jüngeren Patienten unterschieden, wurde der Zusammenhang von Bindung und Mentalisierung im Rahmen zweier Regressionsanalysen genauer untersucht. Dabei zeigte sich, dass bindungsbezogene Angst und bindungsbezogene Vermeidung in der klinischen Gruppe signifikant stärker ausgeprägt sind, jedoch mit jeweils unterschiedlichen Mentalisierungsaspekten einhergehen. Abschließend werden einige Schlussfolgerungen im Hinblick auf die Behandlung älterer Patienten in Psychosomatischen Kliniken gezogen. Schlüsselwörter: Psychosomatische Klinik, ältere Patienten, Gesundheit, Bindung, Mentalisierung
Physiologie des Gehens und der Haltungskontrolle
Authors: Jahn Klaus
Published: March 2022

Aufrechtes Stehen und Gehen sind bei Gesundheit so selbstverständliche Fähigkeiten, dass sie nebenbei gelingen. Im Fall von Erkrankungen verdeutlicht sich die Komplexität der Haltungskontrolle. Dieser Beitrag zeigt, welche Aspekte für Gleichgewicht und Gang wichtig sind. Das Verständnis dafür, was im Einzelfall gestört ist, ist die Voraussetzung für eine gezielte und erfolgreiche Therapie.
Kurse der Nephrologischen WBS-Ulm
Authors: Bundschu Marion
Published: March 2022

Der neue Schulungsort ist das Bantleon Forum (Blaubeurer Straße 32, 89077 Ulm). Informationen zu den Veranstaltungen finden Sie auf
www.wbs-ulm.de

.
Umgang ambulanter Psychotherapeut*innen mit traumatischen Erfahrungen von Patient*innen unter Berücksichtigung einer traumatherapeutischen Zusatzqualifikation
Authors: Lüders Juliane , Sander Christian , Leonhard Anya , Schäfer Ingo , Speerforck Sven , Schomerus Georg
Published: March 2022

Ziel der Studie Untersuchung der Unterschiede im Umgang mit traumatischen Erfahrungen von Patient*innen zwischen Psychotherapeut*innen mit und ohne traumatherapeutischer Weiterbildung (tWB) beziehungsweise Teilqualifikation.

Methodik Onlinebefragung von ambulanten Psychotherapeut*innen (N = 148) zu möglichen Hindernissen in der Thematisierung traumatischer Erfahrungen von Patient*innen sowie dem selbstberichteten berufspraktischen Handeln.

Ergebnisse Das Vorliegen einer tWB ist assoziiert mit einem höheren Kompetenzerleben im berufspraktischen Handeln und weniger Hindernisse in der Thematisierung traumatischer Erfahrungen.

Schlussfolgerung Ein geringeres Kompetenzerleben von Psychotherapeut*innen ohne tWB spricht für den Bedarf obligatorischer Weiterbildungsmaßnahmen. Der Ausbau von niederschwelligen Behandlungsangeboten für Betroffene von traumatischen Erfahrungen und der Abbau von Zugangsbarrieren sind dringend notwendig.
Epoxydibenzo[b,f][1,5]diazocines: From a Hidden Structural Motif to an Efficient Solvent-Free Synthetic Protocol
Authors: Michalak Michał , Depa Wojciech , Bisek Bartosz , Górecki Marcin
Published: March 2022

Epoxydiazocines belong to the rare class of small V-shaped molecules, closely related to Tröger’s base. Due to their intriguing, unique structure, they could serve as molecular building blocks for supramolecular chemistry. An extensive review on their synthesis is contained in this article. Moreover, our recent findings devoted to efficient and easily scalable synthesis of fluorinated epoxy[1,5][b,f]diazocines through solvent-free base-catalyzed condensation of ortho-aminophenones is provided. The unique V-shaped structure was confirmed by X-ray crystal structure analysis. Furthermore, the rigidity of the epoxy­diazocine skeleton allowed for racemate separation and the configuration of enantiomers was established by combining quantum chemical calculations and chiroptical methods.

1 Introduction

2 Synthetic Efforts Towards Epoxydibenzo[b,f][1,5]diazocines

3 Synthetic Efforts Towards Fluorinated Epoxydibenzo[b,f][1,5]diazocines

4 Conclusion
Approaching the legitimacy of self-appointed representatives: from responsiveness to reflexivity
Authors: Nuske Jessica
Published: March 2022

The paper offers an extensive theoretical discussion of and a contribution to the highly relevant, controversial, and normatively charged debate on the legitimacy of interest groups as non-elected, self-appointed representatives. The contribution of this paper is twofold. First, the paper juxtaposes two diverging approaches on legitimacy of interest groups, namely responsiveness as a means to achieve a congruence of interests and reflexivity as the structural facilitation of evaluative judgements conducted by the constituency. Second, the paper proposes a framework on institutional instruments generating reflexivity suitable for empirical research. To corroborate this concept-specification of reflexivity, this paper debates several empirical studies on and theoretical approaches to institutional mobilisation mechanisms enabling a structural facilitation of contestation. Eventually, three distinct attributes of the concept of interest group reflexivity are established. An interest group’s forums for exchange and education, its decision-making system and its grassroots involvement ought to ensure internal structural reflexivity towards its constituency. When combined, they can mitigate the potential for undemocratic representation due to a lack of or skewed mobilisation and empowerment.
Investigating the role of health, education, energy and pollution for explaining total factor productivity in emerging economies
Authors: Yu Yanliang , Alvi Shahzad , Tufail Saira , Nawaz Shahzada M. Naeem , Peng Michael Yao-Ping , Ahmad Nauman
Published: March 2022

This study aims to analyze the role of health, education, energy and pollution in affecting productivity in selected emerging economies. Industrial share to GDP, trade openness and Information Communication and Technology (ICT) are used as control variables. Various dimensions of health and education are explored that include malnutrition, access to clean water, HIV, life expectancy and years of schooling at several levels. A set of Fixed Effect models provide evidence that all of the variables of health and education are critical for productivity. Further, the negative effect of trade openness calls for attention of the policy makers to work out the possibility of technology transfer through integration of economies so that productivity may be enhanced. Another dimension is to revisit the energy mix because the positive effect of energy use is offset by an increase in pollution. Public policy makers should understand the importance of public investment in necessary provisions for improving productivity, economic growth and ultimately the welfare of society, then it can make a difference.
Vibration damping platform for cavity quantum-electrodynamics experiments
Authors: Sauerwein N. , Cantat-Moltrecht T. , Grigoras I. T. , Brantut J.-P.
Published: March 2022

We present a mechanical platform with enhanced vibration damping properties for cavity quantum-electrodynamics experiments. It is based on a composite design that combines a soft, vibration damping core with a rigid shell maintaining optical alignment. It passively damps the vibrations generated by piezoelectric actuators controlling the mirror positions. The mechanical resonances of the platform, which lead to a length change of the cavity, are efficiently suppressed up to 100 kHz. Our platform is ultra-high vacuum compatible and can be used in most applications, in particular, where long cavities and optical access to the cavity center are required.
Electromechanical properties in CaTiO3 modified Na0.5Bi0.5TiO3-BaTiO3 solid solutions above morphotropic phase boundary
Authors: Jurjans M. , Bikse L. , Birks E. , Svirskas Š. , Antonova M. , Kundzins M. , Sternberg A.
Published: March 2022

The structural, electromechanical, and dielectric properties of (1 − x)(0.8Na0.5Bi0.5TiO3-0.2BaTiO3)-xCaTiO3 [(1 − x) (0.8NBT-0.2BT)-xCT] ceramics are studied as candidates for room temperature actuators with high field-induced strain. The choice of 0.8NBT-0.2BT as a starting composition is motivated by the large tetragonality in this concentration range, even though it is located far away from the morphotropic phase boundary. CaTiO3 was chosen as a third component to decrease the depolarization temperature and achieve a high field-induced strain at room temperature. The measured strains at the field-induced phase transition are remarkably lower than might be expected from the jump in unit cell parameters at the phase transition. This inconsistency could be related to an incomplete field-induced phase transition from the ferroelectric phase to the nonpolar phase. Among all of the manufactured samples, the phase transition is close to room temperature in the composition with x = 0.100, which allows obtaining unipolar strains up to 0.23% at E = 65 kV/cm. Electrostrictive-like strain was observed not only above the depolarization temperature but also in the region of field-induced phase transition.
Sparsity-driven synchronization in oscillator networks
Authors: Mihara Antonio , Medeiros Everton S. , Zakharova Anna , Medrano-T Rene O.
Published: March 2022

The emergence of synchronized behavior is a direct consequence of networking dynamical systems. Naturally, strict instances of this phenomenon, such as the states of complete synchronization, are favored or even ensured in networks with a high density of connections. Conversely, in sparse networks, the system state-space is often shared by a variety of coexistent solutions. Consequently, the convergence to complete synchronized states is far from being certain. In this scenario, we report the surprising phenomenon in which completely synchronized states are made the sole attractor of sparse networks by removing network links, the sparsity-driven synchronization. This phenomenon is observed numerically for nonlocally coupled Kuramoto networks and verified analytically for locally coupled ones. In addition, we unravel the bifurcation scenario underlying the network transition to completely synchronized behavior. Furthermore, we present a simple procedure, based on the bifurcations in the thermodynamic limit, that determines the minimum number of links to be removed in order to ensure complete synchronization. Finally, we propose an application of the reported phenomenon as a control scheme to drive complete synchronization in high connectivity networks.
First principles study of 2D half-metallic ferromagnetism in Janus Mn2XSb (X = As, P) monolayers
Authors: Ma Qiuyue , Wan Wenhui , Li Yingmei , Liu Yong
Published: March 2022

Two-dimensional (2D) intrinsic magnetic materials have attracted much attention because of their fascinating physical properties. However, low Curie temperature TC and small magnetic anisotropy energy (MAE) limit their application prospects. Based on the density functional theory, we predict that Janus Mn2AsSb and Mn2PSb monolayers are 2D intrinsic ferromagnetic half-metals. Monte Carlo simulations suggest that the TC values of these monolayers are about 385 and 334 K, respectively. The Mn2AsSb and Mn2PSb monolayers exhibit large MAEs of 415.2 and 450.6 μeV per Mn, respectively. Their ferromagnetism is robust against biaxial strain in the range from −10% to 10%. An energy band calculation with the Heyd–Scuseria–Ernzerhof (HES06) functional indicates that the half-metallic spin bandgaps are about 1.00 and 0.81 eV and the bandgaps on the spin-down channel are 2.67 and 2.53 eV for Mn2AsSb and Mn2PSb monolayers, respectively. These exciting electronic and magnetic properties make Janus Mn2XSb (X = As, P) monolayers promising candidate materials for 2D spintronic devices.
Recrystallization and interdiffusion processes in laser-annealed strain-relaxed metastable Ge0.89Sn0.11
Authors: Abdi S. , Assali S. , Atalla M. R. M. , Koelling S. , Warrender J. M. , Moutanabbir O.
Published: March 2022

The prospect of GeSn semiconductors for silicon-integrated infrared optoelectronics brings new challenges related to the metastability of this class of materials. As a matter of fact, maintaining a reduced thermal budget throughout all processing steps of GeSn devices is essential to avoid possible material degradation. This constraint is exacerbated by the need for higher Sn contents exceeding 8 at. % along with an enhanced strain relaxation to achieve efficient mid-infrared devices. Herein, as a low thermal budget solution for post-epitaxy processing, we elucidate the effects of laser thermal annealing (LTA) on strain-relaxed Ge0.89Sn0.11 layers and Ni-Ge0.89Sn0.11 contacts. Key diffusion and recrystallization processes are proposed and discussed in the light of systematic microstructural studies. LTA treatment at a fluence of 0.40 J/cm2 results in a 200–300 nm-thick layer where Sn atoms segregate toward the surface and in the formation of Sn-rich columnar structures in the LTA-affected region. These structures are reminiscent of those observed in the dislocation-assisted pipe-diffusion mechanism, while the buried GeSn layers remain intact. Moreover, by tailoring the LTA fluence, the contact resistance can be reduced without triggering phase separation across the whole GeSn multi-layer stacking. Indeed, a one order of magnitude decrease in the Ni-based specific contact resistance was obtained at the highest LTA fluence, thus confirming the potential of this method for the functionalization of direct bandgap GeSn materials.
Eulerian peridynamic modeling of microjetting from a grooved aluminum sample under shock loading
Authors: Jin Dingyi , Deng Xiaoliang , Liu Wenyang
Published: March 2022

The micro jetting from a grooved aluminum surface under impact loading is investigated by using Eulerian peridynamics (PD). The simulation results are compared with the published experimental data and the spike velocity model, exhibiting qualitative agreement. The governing mechanism accounting for the formation of micro jetting is elucidated from the perspective of the shock wave interaction with the surface groove. The PD simulation results indicate that the incident shock wave induces progressive groove collapse along the direction of shock wave propagation. The rarefaction waves reflected from the groove edges cause the variation of the velocity vector of PD material points, leading to the material points above and below the symmetric axis of the groove converging toward the symmetric axis and colliding with each other. Then, those collided material points are driven by the incident shock wave propagating along the horizontal symmetric axis and eventually ejected from the groove. The effects of the groove dimensions and the impact velocity on the spike velocity and the ejected mass are discussed. The results show that spike velocity decreases with an increasing groove angle but increases with increasing impact velocity. Furthermore, the ejected mass increases with increasing impact velocity. However, when the depth of the surface groove is fixed and the groove angle increases, the ejected mass first increases and then decreases with the turning point at ∼120°. As the depth of the surface groove increases, the ejected mass increases. The simulation results provide a mechanistic understanding of the micro jetting phenomena and instructive guidance for developing better ejecta models.
Microwave vortex-beam generator based on corrugated metal–insulator–metal ground supported spoof surface plasmon polaritons
Authors: Gu Dezhen , Yang Xiaoqing , Su Piqiang , Peng Huajiang , Jiang Guangming , Wang Jun , Zhou Xin , Li Tingting
Published: March 2022

The vortex beam is an electromagnetic wave that carries orbital angular momentum (OAM). It has an infinite variety of orthogonal modes and provides a new method for increasing wireless communication channels and improving the resolution of radar imaging, therefore it has attracted more attention in recent years. In this paper, a vortex-beam generator is proposed, whose overall structure is made up of a series of circular radiation patches placed on a dielectric substrate and a ground plane, and the ground is composed of corrugated metal–insulator–metal (CMIM). The circular patches are radiating units that can also generate the phase shifts needed for the vortex beam, they are placed in different layers with the spoof surface plasmon polaritons (SSPPs) waveguide to enhance the coupled electric field. The CMIM structure functions both as a waveguide of SSPPs and as the ground plane. Reasonable design, numerical simulation, and experimental measurement show that the generator can generate left and right circularly polarized vortex beams with different OAM modes at different frequencies without changing the structure. And, the generator has many advantages, such as single feed, unidirectional, multi-mode, and small size, and it can be integrated into the system and integrated circuits more easily.
Effect of the odd and even number of blades on the hydrodynamic performance of a pre-swirl pumpjet propulsor
Authors: Qin Denghui , Huang Qiaogao , Pan Guang , Chao Liming , Luo Yang , Han Peng
Published: March 2022

A numerical study based on detached eddy simulations is conducted to investigate the effects of the odd and even number of rotor/stator blades, that is, nr/ns, on the hydrodynamic performance of a pre-swirl pumpjet propulsor (PJP). In this paper, six PJPs, the PJP 6-4 (ns–nr), 8-6, 10-8, 7-5, 9-7, and 11-9, are created. The hydrodynamic performance, the unsteady force of blades, and the wake structure of the PJPs are compared. The results show that the frequency of the fluctuating force of the whole rotor highly depends on the number or, more specifically, the parity of nr. When the parameter nr is the even number, it can be found that the total unsteady force of the rotor blades will be strengthened at the k-order stator-blades-passing frequency (k=1/2nr). Moreover, it indicates that the superposition-enhancement coefficient (is defined as A*) at k=1/2nr equals to nr, at least from the present tests. In terms of both the rotor and stator numbers are even, a phenomenon of the rotor–stator resonance occurs at f=1/2nsnrfn, where fn represents the hub rotational frequency. This work is expected to give some insight in the design of a PJP.
Van der Waals shock polars with multiple or supersonic critical points
Authors: Elling Volker W.
Published: March 2022

It is shown that the γ-van der Waals equation of state (eos) permits shock polars with supersonic critical points, corresponding to critical or strong-type shock reflections that are supersonic, which is not possible for ideal gas. It is also shown that general van der Waals eos permits polars with multiple critical points, corresponding to four or more reflected shocks for the same deflection angle. Of these reflected shocks, at least two are weak-type, i.e., deflection angle increasing with increasing shock strength, so that standard literature has no criteria to select one of the two. Both phenomena can be found with Hugoniot curves entirely in the region of convex and thermodynamically stable eos, avoiding the coexistence region and satisfying various shock stability criteria.
Fluxons in high-impedance long Josephson junctions
Authors: Wildermuth Micha , Powalla Lukas , Voss Jan Nicolas , Schön Yannick , Schneider Andre , Fistul Mikhail V. , Rotzinger Hannes , Ustinov Alexey V.
Published: March 2022

The dynamics of fluxons in long Josephson junctions is a well-known example of soliton physics and allows for studying highly nonlinear relativistic electrodynamics on a microscopic scale. Such fluxons are supercurrent vortices that can be accelerated by bias current up to the Swihart velocity, which is the characteristic velocity of electromagnetic waves in the junction. We experimentally demonstrate slowing down relativistic fluxons in Josephson junctions whose bulk superconducting electrodes are replaced by thin films of a high kinetic inductance superconductor. Here, the amount of magnetic flux carried by each supercurrent vortex is significantly smaller than the magnetic flux quantum Φ0. Our data show that the Swihart velocity is reduced by about one order of magnitude compared to conventional long Josephson junctions. At the same time, the characteristic impedance is increased by an order of magnitude, which makes these junctions suitable for a variety of applications in superconducting electronics.
A 2D Lévy-flight model for the complex dynamics of real-life financial markets
Authors: Yarahmadi Hediye , Saberi Abbas Ali
Published: March 2022

We report on the emergence of scaling laws in the temporal evolution of the daily closing values of the S&P 500 index prices and its modeling based on the Lévy flights in two dimensions (2D). The efficacy of our proposed model is verified and validated by using the extreme value statistics in the random matrix theory. We find that the random evolution of each pair of stocks in a 2D price space is a scale-invariant complex trajectory whose tortuosity is governed by a 2/3 geometric law between the gyration radius Rg(t) and the total length ℓ(t) of the path, i.e., Rg(t)∼ℓ(t)2/3. We construct a Wishart matrix containing all stocks up to a specific variable period and look at its spectral properties for over 30 years. In contrast to the standard random matrix theory, we find that the distribution of eigenvalues has a power-law tail with a decreasing exponent over time—a quantitative indicator of the temporal correlations. We find that the time evolution of the distance of 2D Lévy flights with index α=3/2 from origin generates the same empirical spectral properties. The statistics of the largest eigenvalues of the model and the observations are in perfect agreement.
Hybrid functionals with local range separation: Accurate atomization energies and reaction barrier heights
Authors: Brütting Moritz , Bahmann Hilke , Kümmel Stephan
Published: March 2022

Range-separated hybrid approximations to the exchange–correlation density functional mix exact and semi-local exchange in a position-dependent manner. In their conventional form, the range separation is controlled by a constant parameter. Turning this constant into a density functional leads to a locally space-dependent range-separation function and thus a more powerful and flexible range-separation approach. In this work, we explore the self-consistent implementation of a local range-separated hybrid, taking into account a one-electron self-interaction correction and the behavior under uniform density scaling. We discuss different forms of the local range-separation function that depend on the electron density, its gradient, and the kinetic energy density. For test sets of atomization energies, reaction barrier heights, and total energies of atoms, we demonstrate that our best model is a clear improvement over common global range-separated hybrid functionals and can compete with density functionals that contain multiple empirical parameters. Promising results for equilibrium bond lengths, harmonic vibrational frequencies, and vertical ionization potentials further underline the potential and flexibility of our approach.
Hysteresis-free and μs-switching of D/E-modes Ga2O3 hetero-junction FETs with the BV2/Ron,sp of 0.74/0.28 GW/cm2
Authors: Wang Chenlu , Zhou Hong , Zhang Jincheng , Mu Wenxiang , Wei Jie , Jia Zhitai , Zheng Xuefeng , Luo Xiaorong , Tao Xutang , Hao Yue
Published: March 2022

In this Letter, we report on establishing high performance hysteresis-free and μs-switching depletion/enhancement-mode (D/E-mode) β-Ga2O3 heterojunction (HJ) field effect transistors (FETs) with the state-of-art power figure-of-merit (P-FOM). By optimizing the p-NiOx/n-Ga2O3 interface and n-Ga2O3 recess technology, a positive threshold voltage (VT) as well as a low subthreshold slope can be substantially achieved. The trade-off between the on-resistance (Ron,sp) and breakdown voltage (BV) is improved by incorporation of T-shaped NiOx, resulting in the Ron,sp of 6.24/13.75 mΩ cm2 and the breakdown voltage (BV) of 2145/1977 V for D/E-mode devices and yielding the P-FOM = BV2/Ron,sp to be 0.74/0.28 GW/cm2. To the best of all the authors' knowledge, those P-FOMs are the highest ones among all published lateral Ga2O3 FETs. Benefited from the high-quality interface, a negligible hysteresis of 4 mV and μs-switching can be essentially achieved, showing the great promise of Ga2O3 HJ-FETs for future high-power, high-efficiency, and high-speed power electronics.
Impact of surface roughness on conduction in molecular semiconductors
Authors: Riederer P. , Bouraoui M. , Kersting R.
Published: March 2022

The interface roughness between gate insulator and semiconductor is expected to reduce the conductance of molecular field-effect transistors. This study merges atomic force microscopy data of layer topographies with self-consistent calculations of charge carrier densities and conductances within the channel region. It is found that a roughness equivalent to one monolayer reduces the conductance by nearly 50%. Currents flow mainly within the first monolayer of the semiconductor and along percolation pathways, where charges rarely undergo transfers between adjacent monolayers.
Growth and characterization of high-quality single-crystalline SnTe retaining cubic symmetry down to the lowest temperature studied
Authors: Maiti Ayanesh , Singh Ankita , Iyer Kartik K. , Thamizhavel Arumugam
Published: March 2022

SnTe, an archetypical topological crystalline insulator, often shows a transition from a highly symmetric cubic phase to a rhombohedral structure at low temperatures. In order to achieve the cubic phase at low temperatures, we have grown SnTe employing the modified Bridgman method and studied its properties in detail. Analysis of the crystal structure using Laue diffraction and rocking curve measurements shows a high degree of single crystallinity and mosaicity of the sample. The magnetic susceptibility shows diamagnetic behavior, and the specific heat data match phonon contributions typical of a bulk insulator. Resistivity data exhibit metallic conduction similar to two-dimensional systems, and the signature of the structural transition has not been observed down to the lowest temperature studied. Detailed powder x-ray diffraction measurements show a cubic structure in the entire temperature range studied. This is supported by the angle-resolved photoemission data at low temperatures exhibiting a Dirac cone typical of a topological material. These results demonstrate that the ground state structure of SnTe can be stabilized in the cubic phase, providing a promising platform for quantum applications.
Combining a fractional diffusion equation and a fractional viscosity-based magneto dynamic model to simulate the ferromagnetic hysteresis losses
Authors: Ducharne B. , Sebald G.
Published: March 2022

Magnetic losses in a laminated ferromagnetic core have been studied for years. However, magnetization mechanisms are complex, and the ideal model is still lacking. Classic resolution in the time domain combines a 1D magnetic diffusion equation with a viscosity-based magneto dynamic material law (first-order differential equation). This simultaneous resolution has already been solved by matrix inversion: the diffusion equation temporal term is replaced by its differential equation expression. It leads to a fast solution but overestimates the excess losses linked to the dynamic of the magnetic domains wall motions. Improved material laws using power operators have alternatively been tested. However, it is impossible to regroup the magnetic field terms on the same side of the final equation, and the resolution can only go through complex iterative methods (fixed point, Newton-Raphson). In this study, we propose to combine a fractional diffusion equation and a fractional viscosity-based magneto dynamic differential equation. Matrix resolution is possible, such as an accurate simulation of the dynamic behavior by adjusting the fractional order. The space term of the diffusion equation being solved by space discretization, the combined resolution leads to local information (excitation and induction fields). The number of dynamic parameters is limited but large enough for excellent simulation results.
Apparent permeability of ordered magnetically soft nanowire arrays
Authors: Ripka Pavel , Hrakova Diana , Mirzaei Mehran , Kaman Ondrej
Published: March 2022

Using the equivalent 2D model for finite element method (FEM) we calculated apparent permeability µa and demagnetization factor D for permalloy nanowire and microwire arrays. The simulation results were verified by 3D FEM for arrays up to 3000 wires and experimentally for very large arrays containing up to 40 million wires. We achieved µa = 3 to 33 and coercivities Hc = 1 to 9 kA/m, which are low values for wire arrays. The µa depends mainly on the array geometry; it can be increased by increasing the distance between wires (pitch) and the wire length-to-diameter ratio L/d.
On the anhysteretic magnetization of soft magnetic materials
Authors: Silveyra Josefina María , Conde Garrido Juan Manuel
Published: March 2022

Electrical steels are still the materials of choice for large-scale transformers and most electric motors. Yet, they may present a nonhomogeneous magnetic nature which prevents describing accurately their anhysteretic magnetization with the Langevin-Weiss model. Although interpolation and extrapolation methods may be used to model any anhysteretic curve, a simple and physically-based model would be of great value for fundamental and applied research. Inspired in the law of partial volumes for gas mixtures, we proposed a law of partial magnetizations for magnetic mixtures. In a two-component system, the model leads to the double Langevin-Weiss function. We also introduced a graphical method and a fitting approach to analyze and model anhysteretic magnetization curves. A semi-log magnetization derivative plot is central to this end. We validated our strategy through well-motivated examples using published data on soft magnets. The single Langevin-Weiss function provided an accurate description of the magnetization of isotropic and anisotropic magnetically homogeneous materials: a soft ferrite and a nanocrystalline alloy, respectively. For modelling a magnetization transverse to the material’s preferred direction, the key is to allow a negative molecular field constant. The double Langevin-Weiss function was suitable for less homogeneous materials, such as a grain-oriented electrical steel magnetized along the rolling direction and a non-oriented electrical steel. Moreover, a highly-grain-oriented electrical steel magnetized transverse to the rolling direction, which exhibits a constricted hysteresis loop, could be modeled in excellent agreement with data. The key for the latter, has been to allow an antiparallel arrangement of the mean magnetization of both components.
FORC analysis of nanopatterned vs unpatterned films: Coercivity and switching mechanisms
Authors: Mshar Alecsander D. , Owen Allen G. , Arnold Daniel D. , Visscher Pieter B. , Dumas Randy K. , Gupta Subhadra
Published: March 2022

We have studied the use of self-assembled block copolymers to pattern multilayers of Co and Pd on silicon wafers. Stacks ranging from four to twelve bilayers of Co (0.3 nm)/Pd (0.8 nm) were sputtered onto Ta/Pd seed layers and capped with 3 nm of Ta and were found to have perpendicular magnetic anisotropy as-deposited. The block copolymer polystyrene-block-poly(ferrocenyl dimethylsilane) (PS-b-PFS) was dissolved in toluene and spun onto the wafers. The polymers were phase-separated by heat treatment, leaving self-assembled PFS spheres embedded in PS, which was removed by oxygen-plasma ashing. The PFS spheres were then used as masks to ion-mill the Co/Pd multilayers into nanopillars. To study the effect of etch time and etch angle on the coercivity distribution, we synthesized samples in a Design of Experiments-(DoE)- in these two factors. Scanning electron micrographs showed nanopillars ranging from 15 to 30 nm in diameter, depending primarily on etch time. M-H loops measured on both patterned and unpatterned wafers showed an increase of up to 130% in overall coercivity upon patterning. First Order Reversal Curves (FORC) were measured, and the resulting FORC distributions displayed using a smoothing program (FORCinel) and one that can display the raw data without smoothing (FORC+). We find that FORC+ reveals information about fine-scale structure and switching mechanism that cannot be seen in the smoothed display.
Lysosomal inhibition sensitizes TMEM16A-expressing cancer cells to chemotherapy
Authors: Vyas Avani , Gomez-Casal Roberto , Cruz-Rangel Silvia , Villanueva Hugo , Sikora Andrew G. , Rajagopalan Pavithra , Basu Devraj , Pacheco Jonathan , Hammond Gerald R. V. , Kiselyov Kirill , Duvvuri Umamaheswar
Published: March 2022

Significance

Cisplatin is the first line therapy for patients with head and neck cancer. However, resistance to cisplatin remains a major concern. High expression of the calcium-activated chloride channel TMEM16A in tumors portends poor survival in these patients, possibly because of drug resistance. Here, we show that TMEM16A drives the sequestration of cisplatin into lysosomes. Subsequently, cisplatin is expelled via the delivery of lysosomes to the cell surface. We show that TMEM16A enhances this process, thereby promoting cisplatin resistance. We also show that lysosomal inhibition synergizes with cisplatin to induce tumor cell death. Our data uncovers a new fundamental feature of both lysosomal physiology and cancer cell biology that can potentially impact the treatment of patients with head and neck cancer.
Twenty-first century hydroclimate: A continually changing baseline, with more frequent extremes
Authors: Stevenson Samantha , Coats Sloan , Touma Danielle , Cole Julia , Lehner Flavio , Fasullo John , Otto-Bliesner Bette
Published: March 2022

Significance

Twenty-first century trends in hydroclimate are so large that future average conditions will, in most cases, fall into the range of what we would today consider extreme drought or pluvial states. Using large climate model ensembles, we remove the background trend and find that the risk of droughts and pluvials relative to that (changing) baseline is fairly similar to the 20th century risk. By continually adapting to long-term background changes, these risks could therefore perhaps be minimized. However, increases in the frequency of extremely wet and dry years are still present even after removing the trend, indicating that sustainably managing hydroclimate-driven risks in a warmer world will face increasingly difficult challenges.
Semaphorin 1a-mediated dendritic wiring of the
Drosophila
mushroom body extrinsic neurons
Authors: Lin Chen-Han , Senapati Bhagyashree , Chen Wen-Jie , Bansal Sonia , Lin Suewei
Published: March 2022

Significance

The adult
Drosophila
mushroom body (MB) is one of the most extensively studied neural circuits. However, how its circuit organization is established during development is unclear. In this study, we provide an initial characterization of the assembly process of the extrinsic neurons (dopaminergic neurons and MB output neurons) that target the vertical MB lobes. We probe the cellular mechanisms guiding the neurite targeting of these extrinsic neurons and demonstrate that Semaphorin 1a is required in several MB output neurons for their dendritic innervations to three specific MB lobe zones. Our study reveals several intriguing molecular and cellular principles governing assembly of the MB circuit.
Prevention of antimicrobial prescribing among infants following maternal vaccination against respiratory syncytial virus
Authors: Lewnard Joseph A. , Fries Louis F. , Cho Iksung , Chen Janice , Laxminarayan Ramanan
Published: March 2022

Significance

Strategies to reduce consumption of antimicrobial drugs are needed to contain the growing burden of antimicrobial resistance. Respiratory syncytial virus (RSV) is a prominent cause of upper and lower respiratory tract infections, as a single agent and in conjunction with bacterial pathogens, and may thus contribute to the burden of both inappropriately treated viral infections and appropriately treated polymicrobial infections involving bacteria. In a double-blind, randomized, placebo-controlled trial, administering an RSV vaccine to pregnant mothers reduced antimicrobial prescribing among their infants by 12.9% over the first 3 mo of life. Our findings implicate RSV as an important contributor to antimicrobial exposure among infants and demonstrate that this exposure is preventable by use of effective maternal vaccines against RSV.