bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facet-Sparing Decompression of Lumbar Spinal Stenosis: The Minimally Invasive Bilateral Crossover Approach
Authors: Klingler Jan Helge , Hubbe Ulrich , Scholz Christoph , Krüger Marie T. 
Published: January 2021

AbstractBackground and Study Objective One risk of established decompression techniques for lumbar spinal stenosis is the resection of facet joints, especially if they are steeply configured, promoting destabilization. Minimally invasive bilateral crossover decompression aims to preserve the facet joints and thus stability of the spine. The purpose of this study is to demonstrate the feasibility and early results of this technique.Methods This retrospective case series includes 10 consecutive patients with lumbar stenosis and steep-angle (<35 degrees) facet joints who were treated with minimally invasive bilateral crossover decompression. Eleven segments were decompressed, most commonly L3/L4 (63.6%), followed by L1/L2 and L2/L3 (18.2% each). The effectiveness of surgical decompression was assessed by self-reporting questionnaires.Results After a follow-up of 10.5 months, the Symptom Severity Scale and Physical Function Scale of the Swiss Spinal Stenosis Questionnaire improved by 0.9 (p < 0.05) and 0.7 points, respectively. The mean Oswestry Disability Index improved from 53.9 to 34.6 (p < 0.05). Local and radiating pain under strain showed statistically significant improvement on the Visual Analog Scale (8.9 vs. 5.0 and 8.4 vs. 4.6, respectively). Maximum walking distance increased from 190 to 1,029 m. Apart from one patient requiring surgical decompression of an adjacent segment, there were no reoperations, neurological deteriorations, or other complications.Conclusion The results of this study indicate that minimally invasive bilateral crossover decompression is a promising technique for the treatment of spinal canal stenosis. With its design to spare facet joints, it can potentially reduce the risk of spinal instability, especially in patients with steep facet joints.
Awake Surgical Mitral Valve Repair after Transcatheter Aortic Valve Replacement
Authors: Hirofuji Aina , Kanda Hirotsugu , Kitani Yuya , Kamiya Hiroyuki 
Published: January 2021

AbstractTranscatheter aortic valve replacement has become a popular choice for cases with severe aortic stenosis. However, when severe mitral regurgitation is comorbid in high-risk patients with severe aortic stenosis, therapeutic options must be weighed for each case. Here we present a very frail 88-year-old patient with severe aortic stenosis and severe mitral valve regurgitation who underwent a successful awake minimally invasive mitral valve repair after transcatheter aortic valve replacement.
Intradiskal Injection of Methylene Blue for Discogenic Back Pain: A Meta-Analysis of Randomized Controlled Trials
Authors: Deng Ming , Huang Hui , Ma Yong-gang , Zhou Yan , Chen Qing , Xie Ping 
Published: January 2021

Abstract
Introduction Intradiskal injection of methylene blue has some potential in alleviating discogenic back pain. This meta-analysis aims to explore the impact of intradiskal injection of methylene blue for discogenic back pain.
Methods Several databases such as PubMed, EMbase, Web of Science, EBSCO, and Cochrane Library databases have been searched through November 2019, and randomized controlled trials (RCTs) assessing the effect of intradiskal injection of methylene blue for discogenic back pain are included.
Results Three RCTs are included in the meta-analysis. Overall, compared with control group for discogenic back pain, intradiskal injection of methylene blue remarkably decreased pain scores at 3 months (mean difference [MD] = –0.71; 95% confidence interval [CI] = –0.96 to –0.46; p < 0.00001) and 6 months (MD = –13.92; 95% CI = –22.31 to –5.54; p = 001) and Oswestry Disability Index (ODI) at 4 to 6 weeks (MD = –10.39; 95% CI = –16.95 to –3.83; p = 0.002) and 3 months (MD = –3.66; 95% CI = –4.85 to –2.48; p < 0.00001), but demonstrated no obvious effect on ODI at 6 months (MD = –11.76; 95% CI = –33.33 to 9.80; p = 0.28).
Conclusions Intradiskal injection of methylene blue can substantially decrease pain scores and improve function for discogenic back pain.
Hemorrhagic Suprasellar Central Nervous System Embryonal Tumor in an Adult: Uncommon Features of an Extremely Rare Neoplasm
Authors: Piloni Martina , Gagliardi Filippo , Bailo Michele , Barzaghi Lina Raffaella , Callea Marcella , Terreni Mariarosa , Falini Andrea , Castellano Antonella , Mortini Pietro 
Published: January 2021

Abstract
Background Occurrences of suprasellar central nervous system (CNS) embryonal tumors in adults are extremely rare. Hemorrhagic onset is further uncommon, with only anecdotic cases reported in the literature. The authors describe the case of a 57-year-old man affected by a suprasellar CNS embryonal tumor, with hemorrhagic onset and a unique diffusion pattern along the optic pathways.
Material and Methods A 57-year-old man presenting with acute visual acuity worsening and left homonymous hemianopia was referred to our hospital. Neuroradiologic studies demonstrated an infiltrating, high-grade lesion involving the optic chiasm and right retrochiasmatic pathways with a hemorrhagic area in the ipsilateral pulvinar.
Results The patient underwent microsurgical biopsy. Pathologic assessment confirmed the diagnosis of CNS embryonal tumor, not otherwise specified (NOS) according to the 2016 World Health Organization (WHO) classification of CNS tumors. The patient was referred to a multimodal adjuvant treatment; he eventually died 4 months after surgery. Competent literature has been systematically reviewed in the light of the relevant changes made in the last version of the WHO classification.
Conclusion Embryonal tumors should be considered in the differential diagnosis for sellar and suprasellar space-occupying lesions, despite the rarity of the disease and the uncommon features at time of presentation. As per our knowledge, this is the first case ever described of hemorrhagic suprasellar embryonal tumor with a diffusion pattern along white matter fibers. Histogenesis, biomolecular and neuroradiologic features, and classification of embryonal tumors are an open field of research, with considerable implications for the definition of better diagnostic pitfalls and therapeutic regimens.
Time compression of frequency-modulated pulses in fibres with in-fibre refractive index gratings
Authors: Abramov A.S. , Zolotovskii I.O. , Kamynin V.A. , Lapin V.A. 
Published: January 2021

Abstract
The dynamics of frequency-modulated pulses in fibres with sequentially inscribed refractive-index gratings having a different period is considered. It is shown that the proposed structure of the fibre can be used to generate picosecond and subpicosecond pulses with peak powers on the order of 1 MW.
Experimental technique for studying optical absorption in waveguide layers of semiconductor laser heterostructures
Authors: Bobretsova Yu.K. , Veselov D.A. , Podoskin A.A. , Voronkova N.V. , Slipchenko S.O. , Ladugin M.A. , Bagaev T.A. , Marmalyuk A.A. , Pikhtin N.A. 
Published: January 2021

Abstract
We report a technique for studying the absorption of optical radiation in layers of a semiconductor heterostructure by the method of probe radiation coupling. The studies are carried out using specially made isotype samples based on AlGaAs/GaAs, simulating an n-type doped laser waveguide with a concentration of 1017 – 1018cm−3. The main features of the experimental setup and calculation methods are described. A high (up to 95%) efficiency of light coupling into the waveguide and an error in measuring the absorption coefficient at a level of 0.1 cm−1 are achieved. The possibilities of studying the polarisation and temperature dependences of radiation absorption by free carriers are experimentally demonstrated. It is shown that with an increase in temperature in the range 25 – 85°C, the absorption in the samples increases by 15%.
Simulation on the nonuniform electrical pumping efficiency of THz quantum-cascade lasers
Authors: Dolgov A.K. , Ushakov D.V. , Afonenko A.A. , Dyuzhikov I.N. , Glinskiy I.A. , Ponomarev D.S. , Khabibullin R.A. 
Published: January 2021

Abstract
The efficiency of electric pumping of THz quantum-cascade lasers (QCLs) with strip geometry is studied depending on the number and position of contact pads. The numerical simulation of the electric potential distribution in the THz QCL active region is used to determine the required thicknesses of the upper metallisation layers of the THz QCLs to minimize the voltage drop along the laser structure in the case of nonuniform current supply. It is found that the efficiency of electric pumping in the case of a centrally located contact is significantly higher than when the contact pads are located near the laser structure edges. From the calculated dependence of the THz QCL integral power on the thickness of the upper metal layer, it is shown that for effective current injection, the contact pads must be located at a distance of less than 0.5 mm from each other.
Limiting spectral and angular characteristics of sawtooth dual-relief two-layer diffraction microstructures
Authors: Greisukh G.I. , Ezhov E.G. , Zakharov O.A. , Danilov V.A. , Usievich B.A. 
Published: January 2021

Abstract
Sawtooth two-layer microstructures with internal and external, as well as with two internal reliefs, composed of technological and commercially available optical plastics or an optical plastic and nanocomposite material are investigated. By using the corresponding model microstructures in the frameworks of the rigorous diffraction theory, the limiting spectral and angular characteristics are estimated for sawtooth two-layer dual-relief diffraction microstructures of both types.
Ecological adaptation in European eels is based on phenotypic plasticity
Authors: Enbody Erik D. , Pettersson Mats E. , Sprehn C. Grace , Palm Stefan , Wickström Håkan , Andersson Leif 
Published: January 2021

Significance
Populations within a species may experience genetic adaptation to local environmental conditions while individuals may tolerate variation in environmental conditions due to phenotypic plasticity. European eels reproduce in the Sargasso Sea but spend most of their adult life in highly diverse environmental conditions from northern Europe to North Africa. An unresolved question is whether this species constitutes a single panmictic population or if locally adapted subpopulations occur. Here we conclude, based on whole-genome sequencing, that there is a complete absence of genetic differentiation among eels from different parts of Europe and North Africa. Thus, we postulate that European eels must respond to the extremely diverse ecological conditions they inhabit during the postlarval stages by phenotypic plasticity.
Latent extinction risk of soil fauna in Beijing: a 4-year study from 2013 to 2016
Authors: Wang Wei , Ren Qilin , Zhang Runzhi , Wu Pengxiang 
Published: January 2021

ABSTRACT
Soil ecosystems are far more functionally valuable than previously thought, but soil animals are less visible and often overlooked. Here, we surveyed population sizes of different animal orders in both urban and rural Beijing from 2013 to 2016, to study the impact of increasing urbanization on the ecology of soil fauna. We found 10 orders had less than 1% of soil-animal population in both urban and rural areas. Populations of 6 orders in urban areas were far smaller than those in rural areas. Between 2013 and 2016, both urban and rural areas had experienced a substantial long-term population decrease, and soil animals in Beijing suffered a 52.8% loss of population. Our study indicates 45.5% of orders may be in danger of local extinction, and 27.3% of orders seem highly susceptible to urbanization. Over just four years the soil-animal population in Beijing is shrinking fast thanks largely to increasing urbanization. This raises the worrying prospect of a future soil fauna that may be at risk of local extinction in cities. It is therefore necessary to provide a pragmatic approach to soil-animal diversity conservation. Moreover, the deeper understanding of soil extinction ecology opens up an exciting frontier of opportunities for future research.
Control of double Fano resonances to double optomechanically induced transparencies in a four-mirror cavity set
Authors: uddin Zia , Awais Muhammad , Hussain Ibrar , Ahmad Saeed , Abbas Muqaddar 
Published: January 2021

Abstract
We theoretically demonstrate the characteristics of an output probe field by considering a set of four mirrors that form a cavity system. In a set of four mirrors, two are fixed while two are moveable and each is driven by an external pump field. Each oscillatory mirror has an external plate (mirror) which can generate a Casimir force (CF). The two CFs affect the radiation pressure inside the cavity, influencing the output probe field profile. The double Fano profile is obtained in the presence of CF for different mechanical frequencies as well as for the same mechanical frequencies. Interestingly, we predicted that double Fano resonances occur in the presence of CF, while double optomechanically induced transparency (OMIT) occurs in the absence of CF. The switching between double Fano resonances and double OMIT is also investigated via CF.
Supporting capacity of a ferrofluid ring bearing
Authors: Xie Xingfei , Dai Qingwen , Huang Wei , Wang Xiaolei 
Published: January 2021

Abstract
In this paper, the supporting capacity of a ferrofluids (FFs) ring bearing is investigated experimentally and numerically. The bearing consists of a floating plate, a substrate, and a FFs ring sandwiched between them. The FFs ring is formed and restrained by applying a ring magnet below the substrate. For a FFs ring with a thickness of 0.25 mm, the maximum supporting force is about 1.78 N. Numerical analysis reveals that, compared with the Laplace force, the magnetic force plays a dominating role in the total supporting force. Such a liquid ring support may give underlying applications for frictionless bearings or precision positioning systems.
Compositionally graded III-nitride alloys: building blocks for efficient ultraviolet optoelectronics and power electronics
Authors: Zhang Haochen , Huang Chen , Song Kang , Yu Huabin , Xing Chong , Wang Danhao , Liu Zhongling , Sun Haiding 
Published: January 2021

Abstract
Wide bandgap aluminum gallium nitride (AlGaN) semiconductor alloys have established themselves as the key materials for building ultraviolet (UV) optoelectronic and power electronic devices. However, further improvements to device performance are lagging, largely due to the difficulties in precisely controlling carrier behavior, both carrier generation and carrier transport, within AlGaN-based devices. Fortunately, it has been discovered that instead of using AlGaN layers with fixed Al compositions, by grading the Al composition along the growth direction, it is possible to (1) generate high-density electrons and holes via polarization-induced doping; (2) manipulate carrier transport behavior via energy band modulation, also known as ‘band engineering’. Consequently, such compositionally graded AlGaN alloys have attracted extensive interest as promising building blocks for efficient AlGaN-based UV light emitters and power electronic devices. In this review, we focus on the unique physical properties of graded AlGaN alloys and highlight the key roles that such graded structures play in device exploration. Firstly, we elaborate on the underlying mechanisms of efficient carrier generation and transport manipulation enabled by graded AlGaN alloys. Thereafter, we comprehensively summarize and discuss the recent progress in UV light emitters and power electronic devices incorporating graded AlGaN structures. Finally, we outline the prospects associated with the implementation of graded AlGaN alloys in the pursuit of high-performance optoelectronic and power electronic devices.
Rotating squares auxetic metamaterials with improved strain tolerance
Authors: Sorrentino A , Castagnetti D , Mizzi L , Spaggiari A 
Published: January 2021

Abstract
Rotating squares auxetic metamaterials have the peculiar feature of a negative Poisson’s ratio. This work proposes and examines how an innovative variable arcs fillet solution, at the interconnection regions between the rotating units, improves the structural response of a titanium alloy-based rotating squares metamaterial. Through a 2D finite element (FE) model of the auxetic structure, we investigated and optimized two fillet configurations: first, a double circular arcs profile; second, a combined elliptical and circular arc fillet. According to the FE results, the optimal configuration of the combined elliptical and circular arc fillet allows an overall 3% elastic strain of the metamaterial, with a Poisson’s ratio (PR) equal to ca. −1. In order to assess the deformation behavior of the proposed metamaterial, we performed a tensile test on a prototype of the optimal solution, 3D printed in Onyx material. The experimental displacement field of the specimen, measured through digital image correlation, exhibited excellent agreement with the FE predictions, with a PR equal to ca. −1 up to a 3% overall strain.
A new hyperchaotic complex system and its synchronization realization
Authors: Li Zhengfeng , Zhang Fangfang , Zhang Xue , Zhao Yang 
Published: January 2021

Abstract
In this paper, we propose a new hyperchaotic complex system and systematically study its basic dynamic characteristics such as dissipation, Lyapunov exponent, attractor, parameter changes, and

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cross-section. The system is based on the complex Lorenz chaotic system, and the chaotic system has higher dimensionality and more parameters than complex Lorenz system. We provide a general method for constructing complex chaotic systems. We use the state linear feedback method to realize the synchronization control of the chaotic system as the driving system and the response system and simulate all of the systems by Simulink. The chaotic system and its synchronization simulation are simulated by Simulink to verify their hardware feasibility.
Tunable unidirectional reflectionless propagation in non-Hermitian graphene plasmonic waveguide system
Authors: Ding Jian , Wang Yueke 
Published: January 2021

Abstract
In this paper, a non-Hermitian graphene plasmonic waveguide system is proposed in the mid-infrared region. The proposed structure consists of two resonators and a graphene waveguide, which are attached to the SiO2 substrate. Based on the far-field coupling between the two stub plasmonic resonators, the single-band unidirectional reflectionless phenomenon of fundamental edge plasmonic mode in the non-Hermitian waveguide system has been theoretically studied. It can be found that when plasmonic mode is incident from one side, the reflection is 0, but from the other side, the reflection is 26.212%, so an exceptional point (EP) appears. Furthermore, the EP blueshifts with increasing Fermi level, and is unchanged under different relaxation times. All the simulation results are conducted by finite element method. Therefore, our findings pave a new way for the development of terahertz sensors, diodes, and so on.
Asymmetric defects in one-dimensional photonic lattices
Authors: Jovanović Slavica , Krasić Marija Stojanović 
Published: January 2021

Abstract
The influence of linear and nonlinear asymmetric defects on light beam propagation in a one-dimensional photonic lattice has been numerically analysed. Defects are located in a uniform or composite lattice and can be linear or nonlinear in both cases. The results obtained for the uniform lattice were compared with those obtained for the composite lattice. The asymmetric defect width was varied. It was found that the width of asymmetric defects plays a significant role in light beam propagation. A comparison with the corresponding symmetric defects was also performed. Various types of strongly localized defect modes were found at the defect position as well as in the cavities between the asymmetric defects or an asymmetric defect and the interface. In addition to localized modes, we found reflection and transmission of light.
On the new exact traveling wave solutions of the time-space fractional strain wave equation in microstructured solids via the variational method
Authors: Wang Kang-Jia 
Published: January 2021

Abstract
In this paper, we mainly study the time-space fractional strain wave equation in microstructured solids. He’s variational method, combined with the two-scale transform are implemented to seek the solitary and periodic wave solutions of the time-space strain wave equation. The main advantage of the variational method is that it can reduce the order of the differential equation, thus simplifying the equation, making the solving process more intuitive and avoiding the tedious solving process. Finally, the numerical results are shown in the form of 3D and 2D graphs to prove the applicability and effectiveness of the method. The obtained results in this work are expected to shed a bright light on the study of fractional nonlinear partial differential equations in physics.
Vector NLS solitons interacting with a boundary*
Authors: Zhang Cheng , Zhang Da-jun 
Published: January 2021

Abstract
We construct multi-soliton solutions of the n-component vector nonlinear Schrödinger equation on the half-line subject to two classes of integrable boundary conditions (BCs): the homogeneous Robin BCs and the mixed Neumann/Dirichlet BCs. The construction is based on the so-called dressing the boundary, which generates soliton solutions by preserving the integrable BCs at each step of the Darboux-dressing process. Under the Robin BCs, examples, including boundary-bound solitons, are explicitly derived; under the mixed Neumann/Dirichlet BCs, the boundary can act as a polarizer that tunes different components of the vector solitons. Connection of our construction to the inverse scattering transform is also provided.
Non-line-of-sight transparent object detection and reconstruction based on passive single-pixel imaging
Authors: Li Mengdi , Mathai Anumol , Xu Xiping , Wang Xin , Pan Yue , Gao Xuefeng 
Published: January 2021

Abstract
Single-pixel imaging (SPI) uses point detectors instead of expensive array sensors to capture images under low light conditions. It therefore provides a solution in detecting objects with weak signals. In this research, we propose a non-line-of-sight (NLOS) 2D transparent object inspection system based on SPI technique. The 2D shape of the transparent object is reconstructed using Total Variation Augmented Lagrangian and Alternating Direction Algorithm (TVAL3) approach by collecting indirect light reflected from the object surface. Theoretical analysis shows that 300 illumination patterns are required to reconstruct a

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pixel image, and those patterns are streamed to the digital micromirror device at high speed. Compared to TVAL3 with other methods, better image quality can be obtained with only one-third of illumination patterns. Also, experimental results confirm that this system can obtain transparent object information from reflected light even at a sampling rate of 24%. Furthermore, adjusting the laser wavelength and laser power can improve image quality. The proposed SPI detection system for NLOS transparent objects is an effective method that requires fewer illumination patterns and provides new insights for the detection and reconstruction of NLOS transparent object.