bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcranial Direct Current Stimulation Paired With Verb Network Strengthening Treatment Improves Verb Naming in Primary Progressive Aphasia: A Case Series
Authors: Sheppard Shannon M. , Goldberg Emily B. , Sebastian Rajani , Walker Alexandra , Meier Erin L. , Hillis Argye E.
Published: May 2022

Purpose:

There are few evidence-based treatments for language deficits in primary progressive aphasia (PPA). PPA treatments are often adopted from the poststroke aphasia literature. The poststroke aphasia literature has shown promising results using Verb Network Strengthening Treatment (VNeST), a behavioral therapy that focuses on improving naming by producing verbs and their arguments in phrases and sentences. Emerging research in poststroke aphasia and PPA has shown promising results pairing behavioral language therapy with transcranial direct current stimulation (tDCS).

Method:

This study used a double-blind, within-subjects, sham-controlled crossover design to study the effect of anodal tDCS applied to left inferior frontal gyrus (IFG) plus VNeST versus VNeST plus sham stimulation in two individuals with nonfluent variant PPA and one individual with logopenic variant PPA. Participants received two phases of treatment, each with 15 1-hr sessions of VNeST. One phase paired VNeST with tDCS stimulation, and one with sham. For each phase, language testing was conducted at baseline, and at 1 week and 8 weeks posttreatment conclusion. For each participant, treatment efficacy was evaluated for each treatment phase by comparing the mean change in accuracy between baseline and the follow-up time points for naming trained verbs (primary outcome measure), untrained verbs, and nouns on the Object and Action Naming Battery. Mean change from baseline was also directly compared between tDCS and sham phases at each time point.

Results:

Results revealed a different pattern of outcomes for each of the participants. A tDCS advantage was not found for trained verbs for any participant. Two participants with nonfluent variant PPA had a tDCS advantage for generalization to naming of untrained verbs, which was apparent at 1 week and 8 weeks posttreatment. One participant with nonfluent variant also showed evidence of generalization to sentence production in the tDCS phase.

Conclusion:

VNeST plus anodal tDCS stimulation of left IFG shows promising results for improving naming in PPA.
GIS partial discharge pattern recognition via a novel capsule deep graph convolutional network
Authors: Wang Yanxin , Yan Jing , Ye Xinyu , Qi Zhenkang , Wang Jianhua , Geng Yingsan
Published: May 2022

Deep learning (DL) has attracted significant attention in partial discharge (PD) pattern recognition of gas‐insulated switchgear (GIS). However, the existing DL method extracts numerical information and ignores spatial correlation information. In addition, once the sample size is reduced, model performance is severely degraded. To address these issues, a novel capsule deep graph convolutional network (CDGCN) is employed for GIS PD pattern recognition. First, the GIS PD data is transformed to graph data. Then, the CDGCN is established for GIS PD pattern recognition. The introduction of a ChannelSortPooling layer enriches the graph representation information and filters out the feature values with higher information content. In addition, the multi‐view graph representation is converted to a capsule form, and a capsule network with stronger feature extraction capability is introduced to improve the accuracy of the final graph representation. The results reveal that the proposed CDGCN can effectively diagnose the GIS PD and is more accurate than the traditional DL method. The proposed CDGCN can handle small samples pattern recognition problems and provides a reliable reference for GIS PD pattern recognition.
An adaptive TS‐fuzzy model based RBF neural network learning for grid integrated photovoltaic applications
Authors: Priyadarshi Neeraj , Sanjeevikumar P. , Bhaskar MS , Azam Farooque , Taha Ibrahim B. M. , Hussien Mohamed G.
Published: May 2022

In this research work, an adaptive TS‐fuzzy based RBF neural network (ATSFRBFNN) algorithm based maximum power point tracker (MPPT) is employed for grid integrated photovoltaic (PV) system. The novel learning algorithm provides accurate and rapid PV power tracking under fluctuating solar insolation. However, an improved damping circulating current limiting inverter controller is employed to generate gating signal of voltage source inverter and to deliver reduced harmonic constant, less power loss, mitigation of power quality issues regulation of Dc‐link voltage utilization for grid integrated PV system under steady, and transient weather conditions. The experimental results justify the improved system performance under varying operating conditions. The behaviour of novel hybrid PV MPPT structure is compared with TS‐fuzzy, RBFNN, and GA‐RBF for higher tracking efficacy, least tracking deviation, accurate responses, and zero steady‐state power oscillation around MPP region.
Fast multidimensional dictionary learning algorithms and their application in 3D inverse synthetic aperture radar image restoration and noise reduction
Authors: Mehrpooya Ali , Nazari Milad , Abbasi Zahra , Karbasi Seyed M. , Nayebi Mohammad M. , Bastani Mohammad H.
Published: May 2022

By generalising dictionary learning (DL) algorithms to multidimensional (MD) mode and using them in applications where signals are inherently multidimensional, such as in three‐dimensional (3D) inverse synthetic aperture radar (ISAR) imaging, it is possible to achieve much higher speed and less computational complexity. In this study, the formulation of the multidimensional dictionary learning (MDDL) problem is expressed and two algorithms are proposed to solve it. The first one is based on the method of optimum directions (MOD) algorithm for 1D dictionary learning (1DDL), which uses alternating minimisation and gradient projection approach. As the MDDL problem is non‐convex, the second algorithm approximates the non‐convex objective with a new jointly convex function and efficiently solves it. As an application, we use the proposed methods to restore and denoise the ISAR image. Numerical experiments highlight that the proposed algorithms, in addition to reducing the computational complexity and the amount of required memory, also entail less training data for learning the dictionary, and enjoy higher convergence speed in comparison to their one‐dimensional (1D) counterparts. Specifically, convergence speed of MD algorithms, depending on the size of the training data, is up to at least 10.7 times faster than the equivalent 1DDL algorithm. According to the simulation results, the SNR value achieved by the proposed algorithms is higher than the case where we use the 3D‐IFFT for image reconstruction and the case of fixed dictionaries, by approximately 12 and 4 dB, respectively.
Possible detection of coronal mass ejections on late-type main-sequence stars in LAMOST medium-resolution spectra
Authors: Lu Hong-peng , Tian Hui , Zhang Li-yun , Karoff Christoffer , Chen He-chao , Shi Jian-rong , Hou Zhen-yong , Chen Ya-jie , Xu Yu , Wu Yu-chuan , Cao Dong-tao , Wang Jiang-tao
Published: May 2022

Context. Stellar coronal mass ejections (CMEs) are the primary driver of exoplanetary space weather and may affect the habitability of exoplanets. However, detections of possible stellar CME signatures are extremely rare.

Aims. This work aims to detect stellar CMEs from time-domain spectra observed through the LAMOST Medium-Resolution Spec-troscopic Survey (LAMOST-MRS). Our sample includes 1 379 408 LAMOST-MRS spectra of 226 194 late-type main-sequence stars (Teff < 6000 K, log[g/(cm s−2)] > 4.0).

Methods. We first identified stellar CME candidates by examining the asymmetries of Hα line profiles and then performed double Gaussian fitting for Hα contrast profiles (differences between the CME spectra and reference spectra) of the CME candidates to analyse the temporal variation in the asymmetric components.

Results. Three stellar CME candidates were detected on three M dwarfs. The Hα and Mg I triplet lines (at 5168.94 Å, 5174.13 Å, and 5185.10 Å) of candidate 1 all exhibit a blue-wing enhancement, and the corresponding Doppler shift of this enhancement shows a gradually increasing trend. The Hα line also shows an obvious blue-wing enhancement in candidate 2. In candidate 3, the Hα line shows an obvious red-wing enhancement, and the corresponding projected maximum velocity exceeds the surface escape velocity of the host star. The lower limit of the CME mass is estimated to be ~8 × 1017 g to 4 × 1018 g for these three candidates.
Analysis of the spatio-temporal propagation of drought over Eastern China using complex networks
Authors: Xu Yiran , Lu Fan , Ruan Benqing , Dai Yanyu , Wang Kangming
Published: May 2022

Understanding of the spatio-temporal propagation of drought is a challenging issue as the hydro-climatic processes are inter-connected. Recent developments in network theory offer new avenues to study the propagation of drought. Three metrics that quantify the strength, dominant orientation and distance of droughts are employed to investigate the spatio-temporal propagation. The results show that (1) the network approach based on the event synchronization is a useful tool to study the propagation of drought; (2) The drought events occurring in the south of the study area are more likely to spread outward, and the drought events occurring in the midwestern regions are more likely to be affected by drought events in other regions; (3) The dominant position of drought transmission in the study area has obvious regional characteristics. The midwestern regions are more susceptible to the influence of drought events in the western regions, while other regions are more likely to spread drought events to the inside world. The findings of this paper could help researchers to initially understand the propagation of spatio-temporal droughts over Eastern China.
Water resources carrying capacity model and prediction in Shandong Province based on social and economic factors
Authors: Du Juan , Wang JingTao , Zhang Tao , Wang Shuang
Published: May 2022

In this paper, considering the influence of economic, social, resource and environmental factors on water resources in Shandong Province, a fuzzy comprehensive evaluation model of water resources carrying capacity is established based on DPSIR index system, to evaluate the annual change of water resources carrying capacity in Shandong Province. Then the main influencing factors of total social water consumption are obtained by grey correlation, and the functional relation of total social water consumption is established on regression model. Finally, the development trend of social total water consumption is predicted by time series. The results show that: the development and utilization of water resources in Shandong Province has reached a very high level, water resources are in the stage of scarcity, and the shortage of water resources will continue to intensify in the future. Therefore, it is suggested that comprehensive water resources management policies should be formulated to save and use water resources intensively, in order to ensure the optimal allocation and scientific sustainable utilization of water resources in Shandong Province.
Research on the decision support system for optimal operation of large reservoir power generation
Authors: Li Delong , Wen Tianfu , Xu Xiaohua , Liu Yangyang , Yan Xiaoyu , Jiang Shunxi , Huang Ping
Published: May 2022

In order to give full play to the efficiency of power generation and improve the utilization rate of water resources, the optimal operation of reservoir power generation has become one of the hot researches by the experts and scholars. Luntan Key Water-Control Project is taken as an example, which gives consideration to the comprehensive benefits of flood control and power generation. Based on building both the mathematical models of flood pre-release control and the medium-long term power generation, a decision support system with fast online optimization is developed by using SOA architecture and J2EE technology. The results show the system can improve the operation level of the reservoir power generation, reduce effectively the water abandoning rate, realize the scientific optimal operation, provide scientific basis for the management decision, and create more comprehensive benefits.
Research on the regulation of Three Gorges Reservoir in response to saltwater intrusion in the Yangtze River Estuary
Authors: Cheng Xiaodong , Xu Tao
Published: May 2022

With the changes of economic society and human activities to the natural environment, the impact of saltwater intrusion becomes more frequent and the degree of harm becomes more serious. The Yangtze River Estuary is a densely populated and economically developed area in China, but in terms of water resources utilization, the Yangtze River Estuary is often suffering from saltwater intrustion in dry season. As the backbone of the cascade reservoirs in the Yangtze River Basin, the scientific operation of the Three Gorges Reservoir plays an active role in reducing the saltwater intrusion in the Yangtze River Estuary. Therefore, based on the analysis of the characteristics of Yangtze River Estuary, this paper sums up the variations of saltwater intrusion and discusses the main dynamic factors of saltwater intrusion. In addition, it explores the internal relationship between the upstream water volume and the saltwater intrusion. It takes the allocation of the fresh water resources by the water resources regulation of the Three Gorges Reservoir as a main discussing point. In the end, this paper focuses on the countermeasures and effect of emergency water replenishment on the saltwater intrusion in the Yangtze River Estuary.
Dez Dam Rehabilitation Project Role in Flood Damage Reduction
Authors: Amini Roohollah
Published: May 2022

As a result of climate change, extreme precipitation events from mid-March to April 2019 in southwest Iran generated catastrophic floods taken 78 lives and left $4.1 billion financial damages. The extent of damages could have been even worse without the existence of upstream flood control dams including Dez dam. Dez Dam is the only large dam in its basin which play a significant role in flood control. A multi-purpose rehabilitation project including new power intakes, flushing tunnels and dam heightening with required investment of $350 million is defined in this dam to compensate reservoir live volume losses through 57 years of sedimentation. In this paper, the effect of dam heightening and the flushing tunnels will be evaluated by their roles in flood damage reduction. Assuming that the actual magnitude of a flood cannot be predicted beforehand, a flexible multi-stage routing method considering operator judgment during flood operations is proposed to produce an optimized flood routing policy. The related operation rule is derived for existing and rehabilitated dam and the expected annual damage (EAD) compared in both conditions. The results show that the dam heightening could be considered as an effective way to improve the dam role in flood damage reduction.
Quels barrages pour l’Afrique sahélienne ?
Authors: Lino Michel , de Bonviller Arnaud , Deroo Luc
Published: May 2022

La production hydroélectrique et le développement hydroagricole sont les motivations les plus fréquentes des projets récents en Afrique subsaharienne. En zone sahélienne où la topographie est généralement peu marquée, l’hydroélectricité est pénalisée par le fait que la chute est le plus souvent assurée par le barrage lui-même faute de chute naturelle à valoriser. Le régime hydrologique se caractérise par une saison sèche et une saison humide, imposant une cuvette de régulation importante et donc de forts impacts environnementaux et socioéconomiques (perte de cultures traditionnelles sur les terres fertiles de la plaine inondable, réduction des zones humides et des services qu’elles rendent à l’ensemble des activités, déplacement de population importants, forte évaporation…). La synergie avec le développement agricole et la sauvegarde des cultures traditionnelles est problématique car le planning des lâchures agricoles entre en conflit avec l’optimisation énergétique. Or ces régions possèdent un important potentiel solaire et le coût du kWh solaire est aujourd’hui inférieur à celui de l’hydroélectricité dans le contexte sahélien. L’association d’une centrale solaire (flottante ou à terre) et d’un barrage hydroélectrique permet d’optimiser la performance socioéconomique et environnementale. À travers des exemples, l’article montre l’intérêt de revisiter les projets pour les adapter aux conditions actuelles où les impacts socioéconomiques des retenues sont désormais au coeur des préoccupations et où l’énergie solaire s’impose comme une composante majeure du mix énergétique.
Cochlea-Implantation: Konzept, Therapieergebnisse und Lebensqualität
Authors: Lenarz T. , Büchner A. , Illg A.
Published: May 2022

Cochlea-Implantate stellen heute eine unverzichtbare Methode zur auditiven Rehabilitation hochgradig hörgeschädigter Patienten dar. Durch die rasante Entwicklung der Implantat-technologie haben sich die Hörergebnisse erheblich verbessert, ca 80% der Patienten können telefonieren und Kinder erreichen eine nahezu normale Hör- und Sprachentwicklung. Das hat zu einer Indikationsausweitung hin zu Patienten mit Hochtontaubheit und einseitiger Taubheit geführt. Zur Zeit sind aber nur etwa 60 000 der ca 1 Million CI-Kandidaten implantiert. Zukünftig werden multimodale universelle Hörimplantate für die kombinierte elektro-mechanische Stimulation zur Verfügung stehen, die fortlaufend eine Anpassung der Stimulationsstrategie an den jeweiligen Funktionszustand von Haarzellen und Hörnerven auch bei progredienter Schwerhörigkeit ermöglichen. Brain-Computer-Interfaces erlauben die automatisierte Anpassung an die Hörsituation und eine Optimierung der Signalverarbeitung zur Erzielung eines bestmöglichen Hörvermögens. Binaurale Hörsysteme erlauben eine Verbesserung von Richtungshören und Hören im Störgeräusch. Advanced Implants besitzen additiv gefertigte individualisierte Elektroden, die sich nach atraumatischer robotisch assistierter Insertion aktiv der Anatomie der Cochlea anpassen. Sie sind in Abhängigkeit von der Pathophysiologie mit integrierten biologischen Komponenten ausgestattet, unterstützen die Erhaltung des Restgehörs und ermöglichen die Regeneration neuraler Elemente zur Verbesserung der Elektroden-Nerven-Schnittstelle. Dadurch lassen sich die heutigen grundsätzlichen Grenzen der CI-Technologie überwinden und in Richtung des physiologischen Gehörs verschieben. Das Bionische Ohr ist somit in Reichweite. Durch konsequente Weiterentwicklung mit Vereinfachung der Versorgung, hörerhaltender Implantation unter Lokal-Anästhesie und Anwendung robotischer Systeme werden zukünftig mehr Patienten von dem neuen physiologischen Hören profitieren.
Risk of Periprosthetic Joint Infection after Posttraumatic Hip Arthroplasty following Acetabular Fractures
Authors: Schmidutz Florian , Schreiner Anna Janine , Ahrend Marc-Daniel , Stöckle Ulrich , Maier Sven , Histing Tina , Hemmann Philipp
Published: May 2022

Background Raised complication rates have been reported for total hip arthroplasty (THA) in posttraumatic hip joints after acetabular fractures with prior open reduction and internal
fixation (ORIF). The present study evaluated (I) postoperative surgical site infection and the risk of early infection following THA in posttraumatic hip joints after acetabular fractures
and (II) the discriminatory ability of preoperative C-reactive protein (CRP) blood levels for periprosthetic joint infection (PJI).

Materials and Methods Patients were included who had undergone THA (2014–2019) after prior ORIF, and nonsurgically treated acetabular fractures. Patients’ demographics and the
duration between fracture and THA implantation were assessed. Preoperative diagnostic testing (laboratory results, hip aspirations) as well as the results of intraoperative microbiological
swabs and sonication were also evaluated. Postoperative complications were recorded.

Results Sixty-seven patients (51 men/16 women) were included, with a mean age of 54.7 ± 14.0 years (range: 18.0–82.9). The mean time between acetabular fracture and THA was
13.5 ± 14.9 years (0.2–53.5). Four subgroups were classified: subgroup I (nonsurgical, n = 15), subgroup II (complete removal of osteosynthesis, n = 8), subgroup III (partial removal of
osteosynthesis, n = 15), and subgroup IV (remaining osteosynthesis, n = 29). Preoperative CRP blood levels were normal. CRP levels had no discriminatory ability to predict PJI (AUC: 0.43).
Positive microbiological swabs were assessed in subgroups III (n = 1) and IV (n = 2). Complications during follow-up occurred in subgroups I (one aseptic loosening [6.7%]), III (one wound
revision [6.7%], two low-grade infections [13.3%]), and IV (three low-grade infections [10.3%]).

Conclusion High infection rates were found in patients with THA after acetabular fracture with remaining implants or partial implant removal. Serum CRP alone seems to be a poor
predictor. Therefore, an extensive diagnostic algorithm can help to detect an occult infection, including preoperative hip aspiration (microbiological samples and measurements of synovial
CRP, WBC, and alpha-defensin levels). Intraoperative tissue samples and sonication results should be obtained during THA implantation.
Recognizable Pattern of Arthrogryposis and Congenital Myopathy Caused by the Recurrent TTN Metatranscript-only c.39974-11T > G Splice Variant
Authors: Averdunk Luisa , Donkervoort Sandra , Horn Denise , Waldmüller Stephan , Syeda Safoora , Neuhaus Sarah B. , Chao Katherine R. , van Riesen Anne , Gauck Darja , Haack Tobias , Japp Anna S. , Lee Unaa , Bönnemann Carsten G. , Mayatepek Ertan , Distelmaier Felix
Published: May 2022

Introduction Arthrogryposis is characterized by the presence of multiple contractures at birth and can be caused by pathogenic variants in TTN (Titin). Exons and variants that are not expressed in one of the three major isoforms of titin are referred to as “metatranscript-only” and have been considered to be only expressed during fetal development. Recently, the metatranscript-only variant (c.39974–11T > G) in TTN with a second truncating TTN variant has been linked to arthrogryposis multiplex congenita and myopathy.

Methods Via exome sequencing we identified the TTN c.39974–11T > G splice variant in trans with one of three truncating variants (p.Arg8922*, p.Lys32998Asnfs*63, p.Tyr10345*) in five individuals from three families. Clinical presentation and muscle ultrasound as well as MRI images were analyzed.

Results All five patients presented with generalized muscular hypotonia, reduced muscle bulk, and congenital contractures most prominently affecting the upper limbs and distal joints. Muscular hypotonia persisted and contractures improved over time. One individual, the recipient twin in the setting of twin-to-twin transfusion syndrome, died from severe cardiac hypertrophy 1 day after birth. Ultrasound and MRI imaging studies revealed a recognizable pattern of muscle involvement with striking fibrofatty involvement of the hamstrings and calves, and relative sparing of the femoral adductors and anterior segment of the thighs.

Conclusion The recurrent TTN c.39974–11T > G variant consistently causes congenital arthrogryposis and persisting myopathy providing evidence that the metatranscript-only 213 to 217 exons impact muscle elasticity during early development and beyond. There is a recognizable pattern of muscle involvement, which is distinct from other myopathies and provides valuable clues for diagnostic work-up.
Palladium-Catalyzed Ligand-Free ortho-Deuteration of Aromatic Carboxylic Acids with D2O
Authors: Zhang Ziyin , Jiang Zhi-Jiang , Chen Jia , Cao Yiwei , Gao Zhanghua
Published: May 2022

A ligand-free, palladium-catalyzed ortho-deuteration of aromatic carboxylic acids was developed using D2O as the deuterium source. Compared to their meta-substituted analogues, an unusually lower reactivity in para- and ortho-substituted benzoic acids toward hydrogen isotope exchange was observed. Further investigation revealed that the reaction temperature is a critical parameter for the reactivity, and the modified conditions can afford deuterated products with good to excellent deuterium incorporation.
Magnification in Periodontics: An Overview
Authors: Durgapal Surabhi , Shetty Mamatha
Published: May 2022

A plethora of changes in the concept and the techniques in dental sciences and an increase in patient awareness have spawned demand in advanced dental treatment encompassing elimination of disease with more precision and less discomfort. The use of magnification systems like microscopes is widespread in the medical field, and now it has successfully spread its wings in dentistry. Visual enhancement by using loupes or surgical microscopes can render refinement in the basic surgical procedures. Magnification periodontics refers to the wide range of procedures performed by the use of magnification systems like loupes and microscopes that allow convergence of ideas and efforts, which can make a huge impact on patients. Periodontal procedures are being increasingly performed nowadays that have enabled enhanced outcomes, which were difficult to achieve with the macrosurgery procedures when wound healing and tissue trauma are in consideration. The surgical operating microscope works within the microsurgical triad that includes illumination increased precision and magnification. The incorporation of smaller instruments and sutures and better visualization of the operating site enhance the surgical skills of the clinician. In the past decade, various periodontal procedures from the removal of calculus to the placement of dental implants have been performed using the surgical microscope, which have invariably provided favorable results. It is a topic of interest in the future of periodontal therapy.
Salp-like swimmers inflate, deflate to jet along
Authors: Piccone Ashley
Published: May 2022

Salps fill with fluid to expand, then release it to propel forward, presenting a feasible solution for aquatic soft-body robots.
The design of a high-voltage, long-pulse width, flat-top compensation pulse generator based on metal oxide varistors
Authors: Lu Hao , Zhang Motao , Yang Hanwu , Zhang Huibo , Zhang Zicheng , Gao Jingming
Published: May 2022

In recent years, the pulse forming technology based on metal oxide varistors (MOVs) has been verified to be an effective way to generate high-voltage quasi-square pulses. Due to the limited varistor voltage of a single MOV brick, multiple MOV bricks connected in series are required to stabilize a pulse with high amplitude (larger than hundreds of kV), which leads to the rise of the series inductance of the MOV branch and the flat-top droop in the output waveform. This paper provides two solutions to reduce the influence of the MOV branch inductance on output waveforms. One is that a coaxial evolute structure of the MOV bricks connected in series is designed, which can not only improve the insulation capacity but also reduce the branch inductance. Another is that a flat-top compensation scheme named “PFN-MOV” (Pulse Forming Network) is proposed, which adds an LC filtering branch to shape the signal into a flat-top rising wave with ripple and then offsets the flat-top droop caused by the inductance of the MOV branch. Based on the above ideas, a high-voltage, long-pulse width, flat-top compensation pulse generator is designed and tested, and a quasi-square pulse with voltage amplitude of more than 500 kV, pulse width greater than 800 ns, rise time of less than 50 ns, and flat top of about 600 ns is obtained experimentally. This MOV based generator has the advantage of simple design, compact construction, and better flat top, which is promising to be used as a compact long-pulse driver in many fields, such as high-current accelerator, industrial dedusting, medical sterilization, and cancer treatment.
Correlation between emission and relative intensity noise spectral profiles of an Er-doped fiber superfluorescent source
Authors: Guo Xuanchen , Chai Quan , Zhao Xueying , Ma Shaonian , Xiao Gui , Zhang Jianzhong , Lewis Elfed , Peng Gang-Ding
Published: May 2022

The spectral characteristics of the relative intensity noise (RIN) of two amplified spontaneous emission (ASE) sources are experimentally measured. An Er-doped fiber superfluorescent source (EDF-SFS) is investigated and compared with a super-luminescent diode (SLD) source, using a simple tunable fiber Bragg grating filter-based system. Experimental results based on normal ASE operation conditions showed that the RIN distribution of the EDF-SFS is correlated with its emission spectral profile, which is different from the results observed using the SLD source. This finding shows for the first time that an EDF-SFS based ASE has fundamentally different RIN characteristics from other known existing spontaneous emission broadband sources. The amplifying process of the EDF-SFS is discussed and confirmed using a rate equation-based simulation.
A method to improve multi-node power transmission efficiency of inductively coupled mooring cable
Authors: Zheng Yu , Zhang Shijiang , Fei Chen , Ren Yuanhong , Liu Yingjie
Published: May 2022

The inductively coupled mooring cable is an important tool for monitoring the ocean hydrological data. The mooring cable is an open-loop structure that uses a section of seawater as the transmission medium. The power transmission efficiency of this structure is very low due to the large power loss of the seawater medium, and it is rarely studied. In this paper, a contactless power transmission circuit with seawater loss is analyzed, and the theoretical model of multi-node power transmission of the inductively coupled mooring system is established. In this model, the improvement of the output power and transmission efficiency is only related to the frequency selection and the properties of the magnetic core itself, such as the magnetic core material. Moreover, the optimal scheme is selected according to the output power requirements. The experimental results show that when the input current (Irms) is 2 A, the output power of a single node is 12 W, the total output power is 120 W, and the total transmission efficiency reaches 50%.
Polarization-pinning in substrate emission multi-mode vertical-cavity surface-emitting lasers using deep trenches
Authors: Lei Danqi , Kim Dae-Hyun , Babazadeh Nasser , Childs David T. D. , Hogg Richard A.
Published: May 2022

We investigated the stable polarization-pinning properties of substrate emission InGaAs-based 980 nm multi-mode vertical-cavity surface-emitting lasers (VCSELs). For the multi-mode 40 um diameter aperture VCSELs, we introduced 30 μm wide, 9 μm depth deep trenches that are 15 μm away from the cavity aperture. The VCSELs with trench structure produced higher transverse-electric (TE) polarized light output power, as compared with transverse-magnetic (TM) polarized light output power, namely, the effective TM polarization suppression was realized. These trench-etched VCSELs exhibited a 7.5 dB orthogonal polarization suppression ratio with 16.8 mW of light output power at 60 mA of current injection. The dominant TE polarization distribution was observed in polarization-resolved near-field images of spontaneous and stimulated emission due to the induced strain by the etched trenches.
Computational study of runaway electrons in MST tokamak discharges with applied resonant magnetic perturbation
Authors: Cornille B. S. , Beidler M. T. , Munaretto S. , Chapman B. E. , Del-Castillo-Negrete D. , Hurst N. C. , Sarff J. S. , Sovinec C. R.
Published: May 2022

A numerical study of magnetohydrodynamics (MHD) and tracer-particle evolution investigates the effects of resonant magnetic perturbations (RMPs) on the confinement of runaway electrons (REs) in tokamak discharges conducted in the Madison Symmetric Torus. In computational results of applying RMPs having a broad toroidal spectrum but a single poloidal harmonic, m = 1 RMP does not suppress REs, whereas m = 3 RMP achieves significant deconfinement but not the complete suppression obtained in the experiment [Munaretto et al., Nuclear Fusion 60, 046024 (2020)]. MHD simulations with the NIMROD code produce sawtooth oscillations, and the associated magnetic reconnection can affect the trajectory of REs starting in the core region. Simulations with m = 3 RMP produce chaotic magnetic topology over the outer region, but the m = 1 RMP produces negligible changes in field topology, relative to applying no RMP. Using snapshots of the MHD simulation fields, full-orbit relativistic electron test particle computations with KORC show ≈50% loss from the m = 3 RMP compared to the 10%–15% loss from the m = 1 RMP. Test particle computations of the m = 3 RMP in the time-evolving MHD simulation fields show correlation between MHD activity and late-time particle losses, but total electron confinement is similar to computations using magnetic-field snapshots.
Development of a fully coupled diabatic spin–orbit model for the photodissociation of phenyl iodide
Authors: Weike Nicole , Chanut Emma , Hoppe Hannes , Eisfeld Wolfgang
Published: May 2022

The theoretical treatment of the quantum dynamics of the phenyl iodide photodissociation requires an accurate analytical potential energy surface (PES) model. This model must also account for spin–orbit (SO) coupling. This study is the first step to construct accurate SO coupled PESs, namely, for the C–I dissociation coordinate. The model is based on the Effective Relativistic Coupling by Asymptotic Representation (ERCAR) method developed over the past ten years. The SO-free Hamiltonian is represented in an asymptotic diabatic basis and then combined with an atomic effective relativistic coupling operator determined analytically. In contrast to the previously studied cases (HI, CH3I), the diabatic basis states are due to excitations in the phenyl fragment rather than the iodine atom. An accurate analytical model of the ab initio reference data is determined in two steps. The first step is a simple reference model describing the data qualitatively. This reference model is corrected through a trained artificial neural-network to achieve high accuracy. The SO-free and the fine structure states resulting from this ERCAR model are discussed extensively in the context of the photodissociation.
Novel methodology for systematically constructing global effective models from ab initio-based surfaces: A new insight into high-resolution molecular spectra analysis
Authors: Rey Michael
Published: May 2022

In this paper, a novel methodology is presented for the construction of ab initio effective rotation–vibration spectroscopic models from potential energy and dipole moment surfaces. Non-empirical effective Hamiltonians are obtained via the block-diagonalization of selected variationally computed eigenvector matrices. For the first time, the derivation of an effective dipole moment is carried out in a systematic way. This general approach can be implemented quite easily in most of the variational computer codes and turns out to be a clear alternative to the rather involved Van Vleck perturbation method. Symmetry is exploited at all stages to translate first-principles calculations into a set of spectroscopic parameters to be further refined on experiment. We demonstrate on H2CO, PH3, CH4, C2H4, and SF6 that the proposed effective model can provide crucial information to spectroscopists within a very short time compared to empirical spectroscopic models. This approach brings a new insight into high-resolution spectrum analysis of polyatomic molecules and will be also of great help in the modeling of hot atmospheres where completeness is important.
Improved cross polarized wave generation with an aperture
Authors: Zhao Baozhen , Zhang Xiaohua , Lv Chong , Liu Qiushi , Zhang Ji , Ma Mingjiang , Yang Guoqing
Published: May 2022

A cross polarized wave (XPW) generation experiment with double BaF2 crystals in air was demonstrated with 120 µJ input pulse. A circular aperture was used to truncate the near field profile of the input beam and remove the outer part of the beam, and circularly symmetric beam profiles were generated at the BaF2 crystal positions. The measured focal spot size was close to the diffraction limit, and the energy stability of XPW was improved from ∼1.89% (without the aperture) to ∼0.67% (with the aperture).
High-mobility 2D electron gas in carbon-face 3C-SiC/4H-SiC heterostructure with single-domain 3C-SiC layer
Authors: Sazawa Hiroyuki , Yamaguchi Hirotaka
Published: May 2022

We epitaxially grew a single-domain 3C layer on a step-controlled C-face 4H-SiC substrate to create a 3C/4H-SiC heterostructure. The effectiveness of using such a substrate to grow a thin highly crystalline single-domain 3C layer was demonstrated. The heterostructure exhibited an electron Hall mobility of 7224 cm2/V s at 32 K, which is more than one order of magnitude higher than the best value reported for this structure. From a comparison with the value of 134 m2/V s for a structure with a multi-domain 3C layer, we attribute the high mobility to single-domain formation. The nearly constant sheet carrier density of ∼1.5 × 1013 cm−2 in the temperature range from 34 to 573 K and the high mobility suggest that conduction occurred in a two-dimensional electron gas. Thus, the high potential of C-face 3C/4H heterostructures for high electron mobility transistor applications is displayed.
Optical and electronic effects of rapid thermal annealing at Ir–Ga2O3 interfaces
Authors: Ramdin Daram N. , Haseman Micah S. , Huang Hsien-Lien , Leedy Kevin D. , Hwang Jinwoo , Brillson Leonard J.
Published: May 2022

Ir is a common impurity in the edge-defined film-fed growth method used to produce high-power Ga2O3 device structures and growth substrates; yet, the effects of this deep level defect on carrier transport and recombination, particularly at high device processing and operating temperatures and at metal interfaces, have yet to be explored. The optical and electronic nature of Ir in Ga2O3 and at Ir/ Ga2O3 interfaces change on a near-nanometer to micrometer scale after nitrogen rapid thermal annealing; the understanding and control of which could lower defect-assisted tunneling, improve diode rectification, and preserve critical electric field strength. Depth-resolved cathodoluminescence spectroscopy, interface electronic current, and capacitance–voltage measurements reveal how this dominant impurity in bulk, edge-fed crystal growth diffuses, evolves with temperature, and impacts defect formation and Schottky barrier formation.
Simulating the non-monotonic strain response of nanoporous multiferroic composites under electric field control
Authors: Huang Shu , Karaba Christopher T. , Patel Shreya K. , Neal Amirr , Tolbert Sarah H. , Marian Jaime
Published: May 2022

In this work, we simulate and analyze the mechanical response of a class of multiferroic materials consisting of a templated porous nanostructure made out of cobalt ferrite (CFO) partially filled by atomic layer deposition (ALD) with a ferroelectric phase of lead zirconate titanate (PZT). The strain in the device is measured when an electric field is applied for varying ALD thicknesses, displaying a non-monotonic dependence with a maximum strain achieved for a coating thickness of 3 nm. To understand this behavior, we apply finite element modeling to the smallest repeatable unit of the nanoporous template and simulate the mechanical response as a function of PZT coating thickness. We find that this non-monotonic response is caused by the interplay between two driving forces opposing one another. First, increased porosity works toward increasing the strain due to a reduced system stiffness. Second, decreased porosity involves a larger mass fraction of PZT, which drives the electro-mechanical response of the structure, thus leading to a larger strain. The balance between these two driving forces is controlled by the shear coupling at the CFO/PZT interface and the effective PZT cross section along the direction of the applied electric field. Our numerical results show that considering a nonlinear piezoelectric response for PZT leads to an improved agreement with the experimental data, consistent with ex situ poling of the nanostructure prior to magnetic measurements.
Direct calculation of the functional inverse of realistic interatomic potentials in field-theoretic simulations
Authors: Weyman Alexander , Mavrantzas Vlasis G. , Öttinger Hans Christian
Published: May 2022

We discuss the functional inverse problem in field-theoretic simulations for realistic pairwise potentials such as the Morse potential (widely used in particle simulations as an alternative to the 12-6 Lennard-Jones one), and we propose the following two solutions: (a) a numerical one based on direct inversion on a regular grid or deconvolution and (b) an analytical one by expressing attractive and repulsive contributions to the Morse potential as higher-order derivatives of the Dirac delta function; the resulting system of ordinary differential equations in the saddle-point approximation is solved numerically with appropriate model-consistent boundary conditions using a Newton-Raphson method. For the first time, exponential-like, physically realistic pair interactions are analytically treated and incorporated into a field-theoretic framework. The advantages and disadvantages of the two approaches are discussed in detail in connection with numerical findings from test simulations for the radial distribution function of a monatomic fluid at realistic densities providing direct evidence for the capability of the analytical method to resolve structural features down to the Angstrom scale.
Controlled strained layer epitaxial growth of EuTiO3 on buffered silicon
Authors: Jung F. , Karl H.
Published: May 2022

In this work, we show the epitaxial growth of (111)-oriented EuTiO3 thin films on (001)-oriented silicon with an in situ grown yttria-stabilized zirconia (YSZ) buffer layer by pulsed laser deposition. X-ray diffraction measurements revealed a homogeneously strained EuTiO3 thin film with a strain dependency on the laser fluence during the film growth. From magnetization vs temperature measurements, we confirmed that the strained EuTiO3 films have an antiferromagnetic to ferromagnetic transition at 3.7 K, which disappeared for unstrained films. Furthermore, we used electron backscatter diffraction to analyze the columnar growth of EuTiO3 on YSZ, which showed four in-plane orientations.
High-operating temperature far-infrared Si:Ga blocked-impurity-band detectors
Authors: Deng Ke , Zhang Kun , Li Qing , He Ting , Xiao Yunlong , Guo Jiaxiang , Zhang Tao , Zhu He , Wang Peng , Li Ning , Hu Weida
Published: May 2022

Silicon-based blocked impurity band (BIB) detectors have become the preferred candidate for the astronomical observation field because of their excellent ability for far-infrared detection, easy integration with the readout circuit, and potential for large-scale preparation. We fabricate Si:Ga BIB far-infrared detectors by a molecular beam epitaxy technique with an impressive blackbody specific detectivity of 4.21 × 1011 cm Hz1/2 W−1 at 10 K and nearly uniform broadband response between 2.5 and 20 μm. A response mechanism with variable temperature is described minutely by the varying temperature optoelectronic characterization and theoretical calculation as well as energy band diagram. The substantial results indicate that the responsivity of the detector can steadily maintain up to 26 K for far-infrared. This paper not only increases the accessibility of BIB detectors' fabrication tools but also provides an approach of high-operating temperature far-infrared detectors for astronomy explorations.
Oxygen in antimony triselenide: An IR absorption study
Authors: Herklotz F. , Lavrov E. V. , Hobson T. D. C. , Major J. D. , Durose K.
Published: May 2022

Oxygen in single crystalline antimony triselenide (Sb2Se3) is addressed by infrared (IR) absorption spectroscopy. Measurements conducted on Sb2Se3 samples doped—during growth, post-growth annealing in the O2 ambient, or by O ion implantation—with 16O reveal an IR absorption line at 527 cm−1 (10 K). Substitution of 16O by 18O “red”-shifts the signal down to 500 cm−1 based on which the line is assigned to a local vibrational mode of an isolated oxygen defect. Annealing of O-enriched samples in hydrogen atmosphere at temperatures above 380 °C results in the suppression of the 527-cm−1 line and concurrent appearance of the signals due to hydroxyl groups, suggesting formation of oxygen-hydrogen complexes. The configuration of the 527-cm−1 oxygen center is discussed.
Translation initiation site of mRNA is selected through dynamic interaction with the ribosome
Authors: Chen Yi-Lan , Wen Jin-Der
Published: May 2022

Significance

Ribosomes translate the genetic codes of messenger RNA (mRNA) to make proteins. Translation must begin at the correct initiation site; otherwise, abnormal proteins will be produced. Here, we show that a short ribosome-specific sequence in the upstream followed by an unstructured downstream sequence is a favorable initiation site. Those mRNAs lacking either of these two characteristics do not associate tightly with the ribosome. Initiator transfer RNA (tRNA) and initiation factors facilitate the binding. However, when the downstream site forms structures, initiation factor 3 triggers the dissociation of the accommodated initiator tRNA and the subsequent disassembly of the ribosome–mRNA complex. Thus, initiation factors help the ribosome distinguish unfavorable structured sequences that may not act as the mRNA translation initiation site.
Dynamic transformation between bilayer islands and dinuclear clusters of Cr oxide on Au(111) through environment and interface effects
Authors: Yi Zhiyu , Lin Le , Chang Yuan , Luo Xuda , Gao Junfeng , Mu Rentao , Ning Yanxiao , Fu Qiang , Bao Xinhe
Published: May 2022

Significance

For oxide catalysts, it is important to elucidate and further control their atomic structures. In this work, well-defined CrO
2
bilayer islands and Cr
2
O
7
dinuclear clusters have been grown on Au(111) and unambiguously identified by scanning tunneling microscopy and theoretical calculations. Upon cycled redox treatments, the two kinds of oxide nanostructures can be reversibly transformed. It is interesting to note that both Cr oxides do not exist in bulk but need to be stabilized by the metal surface and the specific environment. Our results suggest that both redox atmosphere and interface confinement effects can be used to construct an oxide nanostructure with the specific chemical state and structure.
Realigning the LIGHT signaling network to control dysregulated inflammation
Authors: Ware Carl F. , Croft Michael , Neil Garry A.
Published: May 2022

Advances in understanding the physiologic functions of the tumor necrosis factor superfamily (TNFSF) of ligands, receptors, and signaling networks are providing deeper insight into pathogenesis of infectious and autoimmune diseases and cancer. LIGHT (TNFSF14) has emerged as an important modulator of critical innate and adaptive immune responses. LIGHT and its signaling receptors, herpesvirus entry mediator (TNFRSF14), and lymphotoxin β receptor, form an immune regulatory network with two co-receptors of herpesvirus entry mediator, checkpoint inhibitor B and T lymphocyte attenuator, and CD160. Deciphering the fundamental features of this network reveals new understanding to guide therapeutic development. Accumulating evidence from infectious diseases points to the dysregulation of the LIGHT network as a disease-driving mechanism in autoimmune and inflammatory reactions in barrier organs, including coronavirus disease 2019 pneumonia and inflammatory bowel diseases. Recent clinical results warrant further investigation of the LIGHT regulatory network and application of target-modifying therapeutics for disease intervention.