bluuebunny/crossref_metadata_2025 huggingface dataset:
Virtual unrolling of spirally-wound lithium-ion cells for correlative degradation studies and predictive fault detection
Authors: Kok Matt D. R. , Robinson James B. , Weaving Julia S. , Jnawali Anmol , Pham Martin , Iacoviello Francesco , Brett Daniel J. L. , Shearing Paul R.
Published: August 2019

This method for virtually unrolling the jelly roll of a lithium ion cell using X-ray CT highlights the predictability of macro deformations formed while cycling. The failure is shown to propagate from nucleation points present since production.
Hydrogen evolution activity tuning via two-dimensional electron accumulation at buried interfaces
Authors: Xue Yudong , Fishman Zachary S. , Wang Yunting , Pan Zhenhua , Shen Xin , Yanagi Rito , Hutchings Gregory S. , Liu Mingzhao , Zheng Shili , Zhang Yi , Altman Eric I. , Hu Shu
Published: August 2019

The buried electrocatalytic interfaces between bimetallic sulfide nanosheets and ALD TiO2 coatings achieved remarkable HER activity improvement, offering a general strategy for improving the charge-transfer kinetics of an electrocatalytic system.
Correction: Consolidating the grain boundary of the garnet electrolyte LLZTO with Li3BO3 for high-performance LiNi0.8Co0.1Mn0.1O2/LiFePO4 hybrid solid batteries
Authors: Xie Huilin , Li Chunli , Kan Wang Hay , Avdeev Maxim , Zhu Chenyou , Zhao Zhikun , Chu Xiaorong , Mu Daobin , Wu Feng
Published: August 2019

Correction for ‘Consolidating the grain boundary of the garnet electrolyte LLZTO with Li3BO3 for high-performance LiNi0.8Co0.1Mn0.1O2/LiFePO4 hybrid solid batteries’ by Huilin Xie et al., J. Mater. Chem. A, 2019, DOI: 10.1039/c9ta03263k.
Effective surface diffusion of nickel on single crystal β-Ga2O3for Schottky barrier modulation and high thermal stability
Authors: Kim Hojoong , Kyoung Sinsu , Kang Taiyoung , Kwon Jang-Yeon , Kim Kyung Hwan , Rim You Seung
Published: August 2019

β-Ga2O3Schottky barrier diodes (SBDs) were demonstrated with Ni Schottky contact deposited by the confined magnetic field-based sputtering (CMFS) method.
Planar transition metal oxides SERS chips: a general strategy
Authors: Hou Xiangyu , Fan Xingce , Wei Penghua , Qiu Teng
Published: August 2019

Group IVB, VB and VIB transition metal oxides planar SERS chips can achieve a low limit of detection below 10−9 M.
Uncovering the microscopic mechanism of incorporating Mn2+ ions into CsPbCl3 crystal lattice
Authors: Xia Jienan , Lu Song , Lei Lei , Hua Youjie , Xu Shiqing
Published: August 2019

Based on a four-precursor synthetic strategy and DFT calculation, we verify that excessive chloride ion concentration benefits the formation of bond [Pb⋯Cl] vacancy pair as well as the subsequent incorporation of [Mn⋯Cl] ion pair.
HPO-Shuffle: an associated gene prioritization strategy and its application in drug repurposing for the treatment of canine epilepsy
Authors: Wang Shuguang , Meng Xiangyu , Wang Yuxing , Liu Yemao , Xia Jingbo
Published: August 2019

Epilepsy is a common neurological disorder that affects mammalian species including human beings and dogs. In order to discover novel drugs for the treatment of canine epilepsy, multiomics data were analyzed to identify epilepsy associated genes. In this research, the original ranking of associated genes was obtained by two high-throughput bioinformatics experiments: Genome Wide Association Study (GWAS) and microarray analysis. The association ranking of genes was enhanced by a re-ranking system, HPO-Shuffle, which integrated information from GWAS, microarray analysis and Human Phenotype Ontology database for further downstream analysis. After applying HPO-Shuffle, the association ranking of epilepsy genes were improved. Afterward, a weighted gene coexpression network analysis (WGCNA) led to a set of gene modules, which hinted a clear relevance between the high ranked genes and the target disease. Finally, WGCNA and connectivity map (CMap) analysis were performed on the integrated dataset to discover a potential drug list, in which a well-known anticonvulsant phensuximide was included.
Subjective Communication Difficulties in Very Mild Aphasia
Authors: Cavanaugh Robert , Haley Katarina L.
Published: August 2019

Purpose

In comparison to the large literature on moderate to severe aphasia, very little is known about aphasia of the mildest severity and whether intervention may be warranted. The purpose of this pilot study was to characterize challenges experienced by people who have recovered to the point that they score normally on aphasia batteries yet report they continue to have aphasia.

Method

Five people with aphasia who scored above the Western Aphasia Battery–Aphasia Quotient (
Kertesz, 2007
) cutoff for aphasia participated in a semistructured interview. A descriptive qualitative design was used to analyze subjective descriptions of difficulties in everyday communication situations within a framework for living with aphasia.

Results

Participants reported salient communication difficulties, reduced social participation, difficulties returning to work, a continual need to concentrate when engaging in language tasks, and a keen awareness of persisting impairments.

Conclusion

People with very mild aphasia experience salient language difficulties, and these difficulties have an adverse effect on multiple domains of living successfully with aphasia. Further investigation toward better methods of assessment and intervention is warranted.
The origin of R CrA variability
Authors: Sissa E. , Gratton R. , Alcalà J. M. , Desidera S. , Messina S. , Mesa D. , D’Orazi V. , Rigliaco E.
Published: August 2019

Context. R CrA is the brightest member of the Coronet star-forming region and is the closest Herbig AeBe star with a spectrum dominated by emission lines. Its luminosity has been monitored since the end of the nineteenth century, but the origin of its variability, which shows a stable period of 65.767 ± 0.007 days, is still unknown.

Aims. We studied photometric and spectroscopic data for this star to investigate the nature of the variability of R CrA.

Methods. We exploited the fact that the near-infrared luminosity of the Herbig AeBe stars is roughly proportional to the total luminosity of the stars to derive the absorption, and then mass and age of R CrA. In addition, we modeled the periodic modulation of the light curve as due to partial attenuation of a central binary by a circumbinary disk. This model reproduces the observations very well.

Results. We found that the central object in R CrA is a very young (1.5 ± 1.5 Myr) highly absorbed (AV = 5.47 ± 0.4 mag) binary; we obtain masses of MA = 3.02 ± 0.43 M⊙ and MB = 2.32 ± 0.35 M⊙ for the two components. We propose that the secular decrease of the apparent luminosity of R CrA is due to a progressive increase of the disk absorption. This might be related to precession of a slightly inclined disk caused by the recently discovered M-dwarf companion. This means that R CrA might be a triple system hosting a disk.
Kindliche Skoliosen
Authors: Bach Christian
Published: August 2019

Bei der Skoliose handelt es sich um eine dreidimensionale Deformität der Wirbelsäule. Bei 80 % der Skoliosen ist die Ursache nicht bekannt und sie werden daher als idiopathisch bezeichnet. Bei den sekundären Skoliosen (20 %) ist die Ursache bekannt. In diese Gruppe fallen auch die kongenitalen und neuromuskulären Skoliosen. Bei Patienten mit idiopathischer Skoliose wird die OP-Indikation üblicherweise ab einem Cobb-Winkel von 45 – 50° gestellt. Die gängigste OP-Technik ist die dorsale Skoliosenkorrektur mit segmentalen Pedikelschrauben zur Maximierung der Stabilität und des Korrekturpotentials, wobei die Techniken der Translation und Derotation angewandt werden. Grundsätzlich sollte bei allen Deformitätenbehandlungen das Spinal Cord Monitoring eingesetzt werden (sensibel und motorisch evozierte Potenziale), um neurologische Störungen bereits frühzeitig intraoperativ erkennen zu können. Eine besondere Herausforderung stellen die Patienten mit early onset Skoliosen dar, da bei diesen Patienten keine definitive Fusion erfolgen darf. Bei dieser Patientengruppe geht es darum zu korrigieren, aber nicht zu fusionieren und lediglich das Wachstum zu lenken (inneres Mieder). Der Einsatz von magnetischen Wachstumsstäben ermöglicht ein weiteres Längenwachstum der Patienten wobei die Nachstellungen ambulant, perkutan und schmerzlos ohne Narkose durchgeführt werden können. Bei Patienten mit kongenitalen Skoliosen ist die Behandlung oft schon sehr früh im Wachstum nötig, wobei man versucht die kongenitale Deformität direkt zu entfernen. Bei Patienten mit starkem Progress der Skoliose (insbesondere bei unsegmented bar) muss die korrigierende Operation schon sehr früh, ab einem Alter von 2 Jahren durchgeführt werden. Diese Operationen sind deutlich anspruchsvoller als die Behandlung von adoleszenten Skoliosen, da Lagerung, Narkoseführung und Instrumentation aufgrund der geringen Größe und des geringen Gewichtes der Patienten schwieriger sind. Bei neuromuskulären Skoliosen besteht das Ziel, die Wirbelsäule wieder ins Lot zu bekommen, wobei das C7-Lot über die Mitte des Sakrums gebracht wird und ein eventueller Beckenschiefstand ausgeglichen werden sollte. Das Ziel der Operation ist die Verbesserung der Lebensqualität und der Sitzfähigkeit.
Perceived Benefits and Barriers Regarding CSII Treatment: Development and Psychometric Evaluation of the Insulin Pump Attitudes Questionnaire (IPA-Questionnaire)
Authors: Bergis Dominik , Roos Timm , Ehrmann Dominic , Schmitt Andreas , Schipfer Melanie , Haak Thomas , Kulzer Bernhard , Hermanns Norbert
Published: August 2019

Background Continuous subcutaneous insulin infusion is the most advanced and demanding form of insulin therapy. Various positive and negative expectations, attitudes and experiences can occur, influencing adherence to and efficacy of continuous subcutaneous insulin infusion therapy. A new questionnaire was developed to systematically assess perceived benefits, perceived barriers and handling of continuous subcutaneous insulin infusion therapy.

Methods The Insulin Pump Attitude Questionnaire was tested in two samples (n=265/452) comprising pump users and non-pump users. Reliability was assessed using Cronbach’s Alpha estimation. Exploratory and confirmatory factor analyses were conducted to establish the factorial structure. Correlations with other questionnaires as well as group differences between pump users and non-pump users were used to assess validity.

Results Exploratory factor analysis revealed 26 items comprising six subscales: “Glycaemic Control”, “Flexibility”, “Impaired Body Image”, “Technology Dependency”, “Ease Of Use” and “Functionality”. Confirmatory factor analysis confirmed this factor structure. The IPA sum score correlated significantly with diabetes distress (r=−0.30), self-efficacy (r=0.22), diabetes empowerment (r=0.36), psychological well-being (r=0.16) and treatment dissatisfaction (r=−0.24), supporting criterion validity with small to medium effect sizes. Furthermore, the IPA was able to differentiate between pump users and non-pump users with higher scores for pump users regarding “Glycaemic Control”, “Flexibility”, “Ease of use” and “Functionality” and lower scores for pump users regarding “Impaired Body Image” and “Technology Dependency”.

Conclusions The Insulin Pump Attitude Questionnaire is a reliable and valid new instrument to assess attitudes towards continuous subcutaneous insulin infusion. With six scales, the Insulin Pump Attitude Questionnaire provides a comprehensive analysis of possible benefits, barriers, and handling problems of continuous subcutaneous insulin infusion therapy. In clinical practice, the Insulin Pump Attitude Questionnaire might be used to address the different attitudes in pump users but also in people considering continuous subcutaneous insulin infusion therapy.
Diagnostic accuracy of Bilateral Inferior Petrosal Sinus Sampling: The Experience of a Tertiary Centre
Authors: Pereira Catarina A. , Ferreira Lia , Amaral Cláudia , Alves Viriato , Xavier João , Ribeiro Isabel , Cardoso Helena
Published: August 2019

Purpose To assess the accuracy of bilateral inferior petrosal sinus sampling both in the differential diagnosis of adrenocorticotrophic hormone dependent Cushing’s syndrome and predicting the localization on the pituitary.

Methods The authors evaluated all patients that undergone bilateral inferior petrosal sinus sampling in a tertiary centre, between January 1995 and March 2018. The probable diagnosis of Cushing’s disease was made when the basal central/peripheral gradient was>2 and/or>3 after stimulation with corticotrophin releasing hormone. The localization was suggested when the inter-sinus gradient was>1.4. The results obtained were compared with the post operatory results: compatible histology and positive immunohistochemistry to adrenocorticotrophic hormone and/or the presence of criteria of cure. Sensitivity, specificity and predictive positive value were calculated.

Results A total of 49 patients were evaluated (75.5% female; mean age 45.4±16.3 years old). Bilateral inferior petrosal sinus sampling was compatible with Cushing’s disease in 27 out of 28 confirmed cases in histology or by criteria of cure, and was compatible with ectopic secretion in the 2 cases confirmed as ectopic secretion of adrenocorticotrophic hormone (sensitivity 96.4%; specificity 100%). The lateralization calculated was concordant with the results after surgery in 17 out of 27 patients with Cushing’s disease – predictive positive value of 63%. Magnetic resonance had a higher predictive value to lateralization – 70.0%.

Conclusions Bilateral inferior petrosal sinus sampling is a safe and reliable procedure to diagnose Cushing’s disease, with great sensitivity and specificity. Nevertheless, the capacity of this procedure to lateralize the lesion inside the pituitary is limited.
Minimally Invasive Stabilization Using Screws and Cement for Pelvic Metastases: Technical Considerations for the Pelvic “Screw and Glue” Technique
Authors: Lea William B. , Neilson John C. , King David M. , Tutton Sean M.
Published: August 2019

Metastatic disease involving the pelvis is common, often resulting in significant pain and disability. Several percutaneous interventions for unstable pelvic metastatic disease have been described, including osteoplasty, ablation, and screw fixation, that when used alone or in combination can significantly reduce pain and disability from metastatic bone disease. While it is possible to make a significant impact in patient care with basic principles and techniques, certain advanced techniques can extend the application of percutaneous interventions while minimizing morbidity.
Necrotizing Enterocolitis: State of the Art in Translating Experimental Research to the Bedside
Authors: Ganji Niloofar , Li Bo , Lee Carol , Filler Rachel , Pierro Agostino
Published: August 2019

Necrotizing enterocolitis (NEC) is a devastating intestinal disease that continues to have high morbidity and mortality among preterm neonates, despite medical advancements in neonatology and neonatal care. To investigate the pathogenesis of the disease and explore novel form of treatment, a variety of experimental models of NEC have been developed and used by various investigators. These experimental models range from in vitro evaluation of intestinal epithelial cells and intestinal organoids to in vivo models of the disease in neonatal mice, rats, and piglets. Most recently, human-derived intestinal organoids have also been developed and investigated. In this review, we will briefly discuss these experimental models and the contributions that they have made to our understanding of NEC. We will also point to the ischemia/reperfusion (I/R) model of intestinal injury which has been used as an indirect model of NEC by some investigators. Advancements in laboratory research into this devastating disease have continued to expand our knowledge on the pathogenesis and prevention of NEC as well as the effectiveness of therapeutic options for management of this severe disease.
Anorectal Malformation: State of the Art in Translating Experimental Research to the Bedside
Authors: Martins José Luiz , Macedo Maurício , Montero Edna Frasson de Souza
Published: August 2019

The embryology of anorectal malformation (ARM) is a controversial issue. The study in humans is difficult due to the scarcity of fetuses with this anomaly. Therefore, ARM animal models, naturally obtained or induced by drugs, have been employed to understand physiopathology and possible treatments. Pigs, rabbits, rats, and mice have been employed as animal models. Additionally, many drugs have been used with this purpose: Etretinate, Ethylenethiourea, and Adriamycin. The animal more frequently used is the rat because of good reproducibility, low cost, and easy handling. Pig is a good model, but it is expensive, and difficult to handling and lodging. Concerning the drugs, Adriamycin promotes a more severe ARM compared with Ethylenethiourea. The models of ARM are of value in the understanding of the embryologic development. Nowadays, researches are aimed at identifying the molecular mechanism of this process, providing the basis for the application of tissue engineering in future experiments with ARM.
Moving Beyond Traditional Understandings of Evidence-Based Practice: A Total Evidence and Knowledge Approach (TEKA) to Treatment Evaluation and Clinical Decision Making in Speech-Language Pathology
Authors: McCurtin Arlene , Murphy Carol-Anne , Roddam Hazel
Published: August 2019

Evidence-based practice (EBP) is a well-established framework for supporting clinical decision making in the discipline of speech-language pathology. The benefits of using evidence to inform clinical practice are acknowledged by clinicians and researchers alike. Even so, after over two decades of EBP advocacy, much clinical uncertainty remains and models supporting the evaluation of interventions require review and reconsideration. The EBP model, while promoting positive principles, can be argued to be conceptually flawed because it suffers from a lack of attention to and explicit valuing of other forms of knowledge crucial to the formation of realistic and judiciously informed decisions. We propose that the evaluation of interventions would be better supported by an explicit knowledge management approach reflecting a range of evidence and knowledge. One worked example is presented to demonstrate what using such an approach can produce in terms of intervention information.
High-responsivity photodetectors made of graphene nanowalls grown on Si
Authors: Li Longfei , Dong Yibo , Guo Weiling , Qian Fengsong , Xiong Fangzhu , Fu Yafei , Du Zaifa , Xu Chen , Sun Jie
Published: August 2019

Graphene nanowalls (GNWs) are wall-like graphene nanosheets that are oriented vertically on a substrate. GNWs have a unique structure and special optoelectronic properties, which enables their use in photodetectors. In this paper, we use plasma-enhanced chemical vapor deposition to directly grow GNWs onto the surface of an n-type lightly doped Si substrate and to optimize the quality of the GNWs by adjusting the growth time and temperature. Furthermore, after the GNWs are lithographically patterned, we use a GNW-Si Schottky structure to develop photodetector arrays which are capable of detecting light from the visible to infrared light spectral range. Throughout the process, GNWs are directly synthesized on a Si substrate without using a catalyst or a transfer step. The process is simple and efficient. Under laser illumination at a wavelength of 792 nm, the highest on/off ratio at zero bias is approximately 105, and the specific detectivity is 7.85 × 106 cm Hz1/2/W. Under a reverse bias of 4 V, the measured responsivity of the detector reaches 1 A/W at room temperature. The device can also produce a light response in the near-infrared band. Upon laser illumination at a wavelength of 1550 nm, the detector shows a responsivity of 12 mA/W at room temperature.
Group-invariant solutions for one dimensional, inviscid hydrodynamics
Authors: McHardy J. D. , Albright E. J. , Ramsey S. D. , Schmidt J. H.
Published: August 2019

In this paper, the results of the Lie group method carried out by Ovsiannikov are utilized to study the one-dimensional hydrodynamic equations governing compressible, inviscid fluid flow in the absence of heat conduction. One-parameter subgroups of the admissible R-parameter Lie group of point transformations of the system are applied to reduce the first-order, non-linear system of partial differential equations (PDE)s to a first-order system of ordinary differential equations (ODE)s. Closed-form solutions to the reduced ODE systems are subsequently determined using a linear velocity profile ansatz. These solutions are valid in one-dimensional (1D) planar, cylindrical and spherical geometries and are connected to solutions of the governing system of PDEs through an inverse map. The linear velocity type solutions were first considered by Sedov in 1953 and constitute a subclass of all possible similarity solutions of the compressible hydrodynamics equations. They further serve as illustrative examples of using solutions obtained for the reduced ODEs to find solutions of the associated system of PDEs. Consequently, the reduced systems of ODEs are provided in their entirety inviting additional solutions to be determined via alternative explicit or numerical solution techniques.
Angular alignment and fidelity of neutron phase-gratings for improved interferometer fringe visibility
Authors: Heacock B. , Sarenac D. , Cory D. G. , Huber M. G. , Hussey D. S. , Kapahi C. , Miao H. , Wen H. , Pushin D. A.
Published: August 2019

The recent development of phase-grating moiré neutron interferometry promises a wide range of impactful experiments from dark-field imaging of material microstructure to precise measurements of fundamental constants. However, the contrast of 3% obtained using this moiré interferometer was well below the theoretical prediction of 30% using ideal gratings. It is suspected that non-ideal aspects of the phase-gratings was a leading contributor to this deficiency and that phase-gratings needed to be quantitatively assessed and optimized. Here we characterize neutron diffraction from phase-gratings using Bragg diffraction crystals to determine the optimal phase-grating orientations. We show well-defined diffraction peaks and explore perturbations to the diffraction peaks and the effects on interferometer contrast as a function of grating alignment. This technique promises to improve the contrast of the grating interferometers by providing in-situ aides to grating alignment.
Design of selector-based insulator-metal transition model for TiO2 bipolar resistive random access memory
Authors: Dai Yuehua , Tao Fei , Qi Min
Published: August 2019

In this study, a NbO2-based selector was designed that can change high resistance states to low resistance states due to the insulator–metal transition (IMT). A one-selector-one-resistor cell for a 3D crossbar array composed of this selector and a TiN/TiO2/TiN bipolar resistive random access memory (RRAM) in series was modeled using the COMSOL finite element multiphysics software package. First, the temperature dependencies of the electrical conductivity (σ), thermal conductivity (kth), and mass specific heat (CP) were used to compare two IMT selectors, which showed that the NbO2-based selector better matched the RRAM due to its appropriate hysteresis width (hw), threshold voltage (Vth), and low off-state current (Ioff). Second, the effect of size variations for the NbO2 on the electrical performance of the IMT selector was investigated. Vth, hold voltage (Vhold), threshold current (Ith), Ioff, and Ith/Ioff ratio of the IMT selector were sensitive to thickness (L) and filament radius (r) of NbO2. L and r were designed by comparing the electrical characteristics of the NbO2 selectors of different sizes to make a connection with the TiO2-based bipolar RRAM. Finally, a TiN/NbO2/TiN/TiO2/TiN stack structure was simulated, and the results show a significantly reduced leakage current (1 μA), high read window (15.8), and improved readout margin (>27 word lines), which are suitable for next-generation high-density memory devices. This study provides guidance for the design of selectors connected to the RRAM, which is beneficial for circuit designs and process manufacturing.
Challenges for reliable internal quantum efficiency determination in AlGaN-based multi-quantum-well structures posed by carrier transport effects and morphology issues
Authors: Frankerl Christian , Hoffmann Marc P. , Nippert Felix , Wang Heng , Brandl Christian , Tillner Nadine , Lugauer Hans-Jürgen , Zeisel Roland , Hoffmann Axel , Davies Matthew J.
Published: August 2019

We report on a systematic study of the determination of the internal quantum efficiency (IQE) in AlGaN-based multiple-quantum-well (MQW) structures using different optical evaluation methodologies and experimental conditions, in order to derive a standard set of measurement conditions for reliable IQE determination. Several potential sources of error that may distort the IQE obtained by optical measurements are discussed, such as carrier transport effects, excitation conditions failing to fulfill ideal resonance conditions, and morphology issues. A series of nominally identical AlGaN-based MQW structures is grown on an AlGaN layer separated by an AlN interlayer of varying thickness. The MQW structures are studied both by resonant and quasiresonant photoluminescence spectroscopy, and IQEs are determined via different commonly employed methods. The obtained values are shown to be significantly affected by the employed excitation conditions, as well as the evaluation techniques. In addition, growth morphology issues and carrier transport effects need to be considered in the interpretation of the measured data, with the latter being investigated in greater detail. The results emphasize the need for an appropriate choice of both experimental conditions and evaluation methodology in order to extract reliable and comparable IQE values.
Data driven nonlinear dynamical systems identification using multi-step CLDNN
Authors: Teng Qi , Zhang Lei
Published: August 2019

In many cases, the equations that dynamical systems are based on are unknown and hard to model and predict. On the other hand, machine learning algorithms are based on the data of a solution as it evolves and do not need equations. In the era of abundant data, using machine learning technology to discover accurate mathematical models of dynamical systems directly from time series data becomes increasingly important. Recently, a multi-step deep neural networks (multi-step DNN) model without need of direct access to temporal gradients is proposed, which can accurately learn the evolution from a given set of observed data, identify nonlinear dynamical systems, and forecast future states. However, the architecture lacks the capability to capture long term temporal dependencies from dynamical time-series data. In the paper, based on the multi-step time-stepping schemes, we proposed a new CLDNN model which combine convolutional layer, long short-term memory layer and fully connected layer, to address the aforementioned weakness. The effectiveness of our model is tested for several benchmark problems involving the identification and prediction of complex, nonlinear and chaotic dynamics. The experiment results show that the multi-step CLDNN has better identification and prediction performance than the multi-step DNN. The research provides possible corroboration for developing new deep learning based algorithms for nonlinear system identification.
Simulation of the two-dimensional Rayleigh-Taylor instability problem by using diffuse-interface model
Authors: Khan Saher Akmal , Shah Abdullah
Published: August 2019

The purpose of this paper is to simulate a two-dimensional Rayleigh-Taylor instability problem using the diffuse-interface formulation of the incompressible Navier-Stokes equations. The governing equations consist of a system of coupled nonlinear partial differential equations for conservation of mass, momentum and phase transport. The Boussinesq approximation is introduced in the momentum equation to relax the complexity of variable density formulation. Due to the simplicity, this approximation can be used for small density variations in simulating two-phase flows. The numerical scheme is based on an artificial compressibility formulation with a finite difference scheme for the space discretization. To validate the method, the penetration of a heavier fluid into the lighter one is computed and illustrated graphically.
Enhanced polarization sensitivity by plasmonic-cavity in graphene phototransistors
Authors: Zhang Donghai , Zhou Jing , Liu Changlong , Guo Shangkun , Deng Jianan , Cai Qingyuan , Li Zhifeng , Zhang Yafeng , Zhang Wenqing , Chen Xiaoshuang
Published: August 2019

Polarization detection is a powerful tool to enhance the information recognition of objects. Although the photodetectors based on graphene with distinguished features have been considered promising for high-performance light perception applications, they are typically polarization insensitive. We proposed and experimentally achieved a plasmonic-cavity integrated graphene phototransistor for polarization detection. The plasmonic cavity enhances the photoresponse of transverse magnetic waves and restrains that of transverse electric waves, leading to a remarkable polarization extinction ratio as high as 30, surpassing those of all previously reported two-dimensional material-based polarization sensitive photodetectors by 3–10 times. In addition, for the selected polarization, the photoresponse is enhanced by more than one order of magnitude due to the enhanced localized field. We chose near-infrared for demonstration, while the principle is applicable to other wavelength ranges.
Optical spectra in the condensed phase: Capturing anharmonic and vibronic features using dynamic and static approaches
Authors: Zuehlsdorff Tim J. , Montoya-Castillo Andrés , Napoli Joseph A. , Markland Thomas E. , Isborn Christine M.
Published: August 2019

Simulating optical spectra in the condensed phase remains a challenge for theory due to the need to capture spectral signatures arising from anharmonicity and dynamical effects, such as vibronic progressions and asymmetry. As such, numerous simulation methods have been developed that invoke different approximations and vary in their ability to capture different physical regimes. Here, we use several models of chromophores in the condensed phase and ab initio molecular dynamics simulations to rigorously assess the applicability of methods to simulate optical absorption spectra. Specifically, we focus on the ensemble scheme, which can address anharmonic potential energy surfaces but relies on the applicability of extreme nuclear-electronic time scale separation; the Franck-Condon method, which includes dynamical effects but generally only at the harmonic level; and the recently introduced ensemble zero-temperature Franck-Condon approach, which straddles these limits. We also devote particular attention to the performance of methods derived from a cumulant expansion of the energy gap fluctuations and test the ability to approximate the requisite time correlation functions using classical dynamics with quantum correction factors. These results provide insights as to when these methods are applicable and able to capture the features of condensed phase spectra qualitatively and, in some cases, quantitatively across a range of regimes.
Formation of quasi-periodic slow magnetoacoustic wave trains by the heating/cooling misbalance
Authors: Zavershinskii D. I. , Kolotkov D. Y. , Nakariakov V. M. , Molevich N. E. , Ryashchikov D. S.
Published: August 2019

Slow magnetoacoustic waves are omnipresent in both natural and laboratory plasma systems. The wave-induced misbalance between plasma cooling and heating processes causes the amplification or attenuation, and also dispersion, of slow magnetoacoustic waves. The wave dispersion could be attributed to the presence of characteristic time scales in the system, connected with the plasma heating or cooling due to the competition of the heating and cooling processes in the vicinity of thermal equilibrium. We analyzed linear slow magnetoacoustic waves in a plasma in thermal equilibrium formed by a balance of optically thin radiative losses, field-align thermal conduction, and an unspecified heating process. The dispersion is manifested by the dependence of the effective adiabatic index of the wave on the wave frequency, making the phase and group speeds frequency-dependent. The mutual effect of the wave amplification and dispersion is shown to result in the occurrence of an oscillatory pattern in an initially broadband slow wave, with the characteristic period determined by the thermal misbalance time scales, i.e., by the derivatives of the combined radiation loss and heating function with respect to the density and temperature, evaluated at the equilibrium. This effect is illustrated by estimating the characteristic period of the oscillatory pattern, appearing because of thermal misbalance in the plasma of the solar corona. It is found that by an order of magnitude, the period is about the typical periods of slow magnetoacoustic oscillations detected in the corona.
Ohmic loss analysis for coaxial cavities of high-power high-frequency gyrotrons
Authors: Zhang Shan , Xue Qianzhong , Wang Xuewei , Wang Kai , Zhao Ding
Published: August 2019

Coaxial cavities are the main interaction structures of high-power high-frequency gyrotrons at present. With the increase of operating frequency and output power, ohmic loss becomes to be a vital issue needed to be analyzed compulsorily for coaxial-cavity gyrotron. It would lead to operating frequency shift and efficiency decline. In addition, the long pulse operation would be deteriorated to a large extent as a consequence of rather severe ohmic losses. Therefore, it is of great meaning to analyze the ohmic losses of coaxial cavity more accurately. In this paper, a new method is introduced to analyze the influence of the ohmic losses on coaxial cavities and TE34,11 mode operating at 170 GHz is taken as an example to compare this method with other two methods. The results show that this method can be used to analyze the coaxial cavity with higher accuracy and fewer restrictions.
Self-assembled interface monolayers for organic and hybrid electronics
Authors: Sizov Alexey S. , Agina Elena V. , Ponomarenko Sergey A.
Published: August 2019

The state of the art in the field of self-assembled organic interface monolayers widely used in organic and hybrid electronics is analyzed and the results obtained are summarized. Recent advances in full and local substrate modification using interface layers are considered in detail. Examples of the most successful applications of interface monolayers as monolayer dielectrics, modifiers of the work function and adhesion promoters are given. The advantages of utilizing interface monolayers at semiconductor/dielectric interfaces and for modifying the semiconductor surface are demonstrated. Specific features of formation of nanostructured surfaces including those used in biosensoric applications are outlined.

The bibliography includes 139 references.
Antisymmetric paramodular forms of weight 3
Authors: Gritsenko V. A. , Wang H.
Published: August 2019

The problem of the construction of antisymmetric paramodular forms of canonical weight

has been open since 1996. Any cusp form of this type determines a canonical differential form on any smooth compactification of the moduli space of Kummer surfaces associated to

-polarised abelian surfaces. In this paper, we construct the first infinite family of antisymmetric paramodular forms of weight

as automorphic Borcherds products whose first Fourier-Jacobi coefficient is a theta block.

Bibliography: 32 titles.
Relationship between high angle grain boundaries and hardness after γ→α transformation
Authors: Wu B. B. , Wang Z. Q. , Wang X. L. , Zhao J. X. , Shang C. J. , Misra R. D. K.
Published: August 2019

This study is devoted to establish the relationship between high angle grain boundaries (HAGBs) and hardness from crystallography and provide reference for improving the hardenability of high strength ultra-heavy plate steel. The starting temperature during γ→α phase transformation was significantly decreased with the addition of boron (B). Electron backscattered diffraction and grain boundary density statistical results showed that the hardness follows a near linear relationship with the density of HAGBs. The variants of closed-packed (CP) grouping produces higher density of HAGBs and corresponding hardness than Bain grouping, such that a qualitative description that combines Jominy curves with transformation mode is proposed to evaluate hardenability.
GTP-tubulin loves microtubule plus ends but marries the minus ends
Authors: Wordeman Linda
Published: August 2019

Microtubule minus ends are inherently more stable than plus ends despite the fact that free tubulin associates more avidly to the plus end. In this issue, Strothman et al. (2019. J. Cell Biol. https://doi.org/10.1083/jcb.201905019) measure, for the first time, the off-rate for GTP-tubulin and find that it is different for the two ends, suggesting that this parameter may control the transition to disassembly at microtubule ends.
KCNMA1-linked channelopathy
Authors: Bailey Cole S. , Moldenhauer Hans J. , Park Su Mi , Keros Sotirios , Meredith Andrea L.
Published: August 2019

KCNMA1 encodes the pore-forming α subunit of the “Big K+” (BK) large conductance calcium and voltage-activated K+ channel. BK channels are widely distributed across tissues, including both excitable and nonexcitable cells. Expression levels are highest in brain and muscle, where BK channels are critical regulators of neuronal excitability and muscle contractility. A global deletion in mouse (KCNMA1−/−) is viable but exhibits pathophysiology in many organ systems. Yet despite the important roles in animal models, the consequences of dysfunctional BK channels in humans are not well characterized. Here, we summarize 16 rare KCNMA1 mutations identified in 37 patients dating back to 2005, with an array of clinically defined pathological phenotypes collectively referred to as “KCNMA1-linked channelopathy.” These mutations encompass gain-of-function (GOF) and loss-of-function (LOF) alterations in BK channel activity, as well as several variants of unknown significance (VUS). Human KCNMA1 mutations are primarily associated with neurological conditions, including seizures, movement disorders, developmental delay, and intellectual disability. Due to the recent identification of additional patients, the spectrum of symptoms associated with KCNMA1 mutations has expanded but remains primarily defined by brain and muscle dysfunction. Emerging evidence suggests the functional BK channel alterations produced by different KCNMA1 alleles may associate with semi-distinct patient symptoms, such as paroxysmal nonkinesigenic dyskinesia (PNKD) with GOF and ataxia with LOF. However, due to the de novo origins for the majority of KCNMA1 mutations identified to date and the phenotypic variability exhibited by patients, additional evidence is required to establish causality in most cases. The symptomatic picture developing from patients with KCNMA1-linked channelopathy highlights the importance of better understanding the roles BK channels play in regulating cell excitability. Establishing causality between KCNMA1-linked BK channel dysfunction and specific patient symptoms may reveal new treatment approaches with the potential to increase therapeutic efficacy over current standard regimens.
Optimizing robot motion for robotic ultrasound-guided radiation therapy
Authors: Schlüter Matthias , Fürweger Christoph , Schlaefer Alexander
Published: August 2019

An important aspect of robotic radiation therapy is active compensation of target motion. Recently, ultrasound has been proposed to obtain real-time volumetric images of abdominal organ motion. One approach to realize flexible probe placement throughout the treatment fraction is based on a robotic arm holding the ultrasound probe. However, the probe and the robot holding it may obstruct some of the beams with a potentially adverse effect on the plan quality. This can be mitigated by using a kinematically redundant robot, which allows maintaining a steady pose of the ultrasound probe while moving its elbow in order to minimize beam blocking. Ultimately, the motion of both the beam source carrying and the ultrasound probe holding robot contributes to the overall treatment time, i.e. beam delivery and robot motion. We propose an approach to optimize the motion and coordination of both robots based on a generalized traveling salesman problem. Furthermore, we study an application of the model to a prostate treatment scenario. Because the underlying optimization problem is hard, we compare results from a state-of-the-art heuristic solver and an approximation scheme with low computational effort. Our results show that integration of the robot holding the ultrasound probe is feasible with acceptable overhead in overall treatment time. For clinically realistic velocities of the robots, the overhead is less than 4% which is a small cost for the added benefit of continuous, volumetric, and non-ionizing tracking of organ motion over periodic x-ray-based tracking.
Memory cost of temporal correlations
Authors: Budroni Costantino , Fagundes Gabriel , Kleinmann Matthias
Published: August 2019

A possible notion of nonclassicality for single systems can be defined on the basis of the notion of memory cost of classically simulating probabilities observed in a temporal sequence of measurements. We further explore this idea in a theory-independent framework, namely, from the perspective of general probability theories (GPTs), which includes classical and quantum theory as special examples. Under the assumption that each system has a finite memory capacity, identified with the maximal number of states perfectly distinguishable with a single measurement, we investigate what are the temporal correlations achievable with different theories, namely, classical, quantum, and GPTs beyond quantum mechanics. Already for the simplest nontrivial scenario, we derive inequalities able to distinguish temporal correlations where the underlying system is classical, quantum, or more general.
Evaluation of methodologies for computing the deep brain stimulation volume of tissue activated
Authors: Duffley Gordon , Anderson Daria Nesterovich , Vorwerk Johannes , Dorval Alan D , Butson Christopher R
Published: August 2019

Objective. Computational models are a popular tool for predicting the effects of deep brain stimulation (DBS) on neural tissue. One commonly used model, the volume of tissue activated (VTA), is computed using multiple methodologies. We quantified differences in the VTAs generated by five methodologies: the traditional axon model method, the electric field norm, and three activating function based approaches—the activating function at each grid point in the tangential direction (AF-Tan) or in the maximally activating direction (AF-3D), and the maximum activating function along the entire length of a tangential fiber (AF-Max). Approach. We computed the VTA using each method across multiple stimulation settings. The resulting volumes were compared for similarity, and the methodologies were analyzed for their differences in behavior. Main results. Activation threshold values for both the electric field norm and the activating function varied with regards to electrode configuration, pulse width, and frequency. All methods produced highly similar volumes for monopolar stimulation. For bipolar electrode configurations, only the maximum activating function along the tangential axon method, AF-Max, produced similar volumes to those produced by the axon model method. Further analysis revealed that both of these methods are biased by their exclusive use of tangential fiber orientations. In contrast, the activating function in the maximally activating direction method, AF-3D, produces a VTA that is free of axon orientation and projection bias. Significance. Simulating tangentially oriented axons, the standard approach of computing the VTA, is too computationally expensive for widespread implementation and yields results biased by the assumption of tangential fiber orientation. In this work, we show that a computationally efficient method based on the activating function, AF-Max, reliably reproduces the VTAs generated by direct axon modeling. Further, we propose another method, AF-3D as a potentially superior model for representing generic neural tissue activation.
Selected laser-induced plasma spectroscopy: From medical to astrophysical applications
Authors: Parigger C G , Sherbini A M EL , Splinter R
Published: August 2019

This work discusses laboratory experiments using atomic and molecular spectroscopy for diagnosis of laser-induced phenomena of interest in the field of medicine, and in astronomy for the understanding of recorded spectra from selected stars. Photo-acoustic spectroscopy utilizes femtosecond laser-pulse trains for diagnostic and therapeutic applications. Optical emission spectroscopy explores nominal nanosecond laser-induced, nano-particle plasma and its detection sensitivity. The study of laboratory plasma generated in selected gas-mixtures reveals insights for the interpretation of white dwarf spectra.
Phase transition induced by CW-laser in a finite silver selenide (Ag2 Se) according to (HHCE) model
Authors: El-Adawi M K , Shalaby S A
Published: August 2019

Thermal effects induced in a finite silver selenide slab by CW laser source are studied. The hyperbolic heat conduction equation (HHCE) in dimensionless form is solved using Laplace integral transform technique. Different laser power densities are considered. Expression for the temperature field within the target is obtained. As an illustrative example, the critical time required to initiate phase transition and that required to initiate melting are computed for different pulses.
Magnetically charged black hole
Authors: Khaled Nada , Elashri Mohamed
Published: August 2019

In this study, the concept of magnetically charged black hole is discussed through calculating the angular momentum (L) of its interaction with an electric test charge. Results confirm that the angular momentum form will agree with the prediction of no-hair theorem and we will show that L will depend on the distance between the charge and the black hole.
J-matrix calculation of Tsallis entropy for Hellmann potential
Authors: Nasser Ibraheem
Published: August 2019

Abstract The Tsallis entropy for a system that interrelates with the Hellmann potential is calculated and discussed. The calculation is done in the position and momentum spaces using the J-matrix method. Most of our outcomes are reported for the first time. The results are compared with the available literature results.
Positron annihilation apectroscopy on colloidal CuIn1-xGaxSe2 semiconductor sanocrystals
Authors: Elsaka B.A. , Eissa A. , Ghali M. , Sharshar T.
Published: August 2019

Simple and low-cost hot-injection method was used to synthesize three samples of colloidal nanocrystals with general chemical formula CuIn1-xGaxSe2 (x=0.0, 0.6 and 0.82). X-ray diffraction (XRD) and transmittance electron microscopy (TEM) have been used to investigate the structural properties of the synthesized nanocrystals and proved their high crystallinity. Positron annihilation lifetime (PAL) and Doppler broadening (DB) techniques were used to give more insights on the structural defects of the grown samples. The results of the positron lifetime measurements indicate that the shortest lifetime component (τ
1) with intensity ≳ 97% is greater than the calculated positron bulk lifetime, 235-240 ps. This indicates that the concentrations of the vacancy-type defects for the as-synthesized CuIn1-xGaxSe2 samples are greater than the saturation trapping limit (1018 cm-3). Moreover, results of the PAL measurements and the theoretically calculated positron lifetimes indicate that Cu-Se, In-Se and/or Ga-Se are the dominant vacancy-type defect for all studied range of Ga. Also, the results show that the vacancy-type defect concentrations of samples with Ga content of 0.6 and 0.82 are reduced compared with that for zero-Ga content sample.