bluuebunny/crossref_metadata_2025 huggingface dataset:
Covid-19-Related Acute Invasive Fungal Sinusitis: Clinical Features and Outcomes
Authors: Abdelsamie Alaa Mohamed , Abdelazim Hossam Mohamed , Elnems Mohamed Goda , Abdelhakam Rehab Bassam , Abdelalim Abdelrahman Ahmed
Published: January 2022

Introduction There is a noticeable increase in the incidence of acute invasive fungal sinusitis which coincides with the ongoing coronavirus pandemic. It is a potentially-lethal fungal infection, with the most common form being the rhino-orbito-cerebral presentation.

Objectives The aim of the present study is to discuss the different epidemiological factors, risk factors, clinical presentations and outcomes of acute invasive fungal sinusitis which is noticeably related to the coronavirus disease 2019 (Covid-19) pandemic.

Methods The present cross-sectional cohort study included 22 adult patients who presented with Covid-19-related acute invasive fungal sinusitis. The diagnosis of acute invasive fungal sinusitis was confirmed by histopathological biopsy. All data, including demographics, risk factors, clinical findings, different lines of treatment and their outcomes, were recorded and analyzed.

Results All patients had diabetes mellitus (100%), and 17 (77.3%) had been submitted to systemic steroids. All patients (100%) had unilateral sinonasal disease. Proptosis was found in 15 patients (68.2%), ophthalmoplegia was observed in 12 patients (54.5%), and intracranial affection occurred in 10 patients (45.5%). A total of 20 patients (90.9%) received liposomal amphotericin B. Surgical debridement was performed in 18 patients (45.5%). Non-septated mycelia was present in 19 biopsies (86.4%), while 3 (13.6%)showed septated mycelia. Total improvement was achieved in 10 patients (45.5%), while the mortality rate was of 27.3% (6 out of 22 participants).

Conclusion Diabetes mellitus is the most common preexisting medical condition associated with Covid-19-related acute invasive fungal sinusitis. Systemic corticosteroid therapy is considered a predisposing factor. It is necessary to raise the level of awareness to diagnose this condition, especially in patients with Covid-19 infection or those who have recently recovered from it.
ENT Manifestations in Patients Suffering from COVID-19: Study from a COVID Hospital in North India
Authors: Srivastava Anitya , Agarwal Ashish Chandra , Alam Syed Zeeshan
Published: January 2022

Introduction COVID-19 has been one of the worst pandemics faced by the human civilization, and otorhinolaryngological manifestations are commonly seen in this disease.

Objective The present study was done to profile the ear, nose, and throat (ENT) manifestations in patients diagnosed with COVID-19. An attempt has also been made to assess whether there was any difference between the symptoms of different strains of COVID-19. A brief review of the current knowledge of the transmission of the disease and its treatment has also been done.

Methods A cross-sectional, record-based study was conducted in a COVID hospital of India between May and July 2020. Descriptive statistics were used and appropriate parametric/nonparametric tests were applied to assess the association between various variables.

Results Out of 250 patients, 80 cases were asymptomatic and 170 were symptomatic. Most of the symptomatic patients had sore throat and nasal congestion.

Conclusion Knowledge of the ENT manifestations of COVID-19 is essential for its early identification and to devise appropriate prevention protocols for the benefit of health care workers (HCWs) and of the general population.
Clinical Characteristics of a Zoonotic Occupational Disease—Brucella endocarditis with Review of Literature
Authors: Anilet Vasanth Kataria , Tammiraju Iragavarapu , Koduri Meena
Published: January 2022

Background Brucellosis is a zoonotic bacterial infection caused by a gram-negative aerobic coccobacillus. It can have varied presentation. Most severe complications include neurological and cardiovascular involvement (most commonly in the form of infective endocarditis). Aortic valve is most commonly involved (75%). Blood culture is highly specific, while serologic tests are more sensitive for diagnosing brucellosis. Transthoracic and transesophageal echocardiography plays a major role in diagnosing infective endocarditis. Treatment of Brucella endocarditis includes combination of antibiotic therapy and surgical valve replacement. We are presenting here a case series of seven cases of B. endocarditis with different presentations and varied underlying cardiac conditions.

Materials and Methods Total seven cases of B. endocarditis were reported. The age group ranges from 22 to 45 years. Majority of them were from agriculture and dairy industry. All have presented with fever and three patients had severe breathlessness. Three cases were rheumatic valve diseases, one was bicuspid aortic valve, and one was congenital heart disease with prosthetic valve. Six patients had native valve endocarditis (four had predisposing cardiac condition with diseased valves, two had normal valves), whereas one had prosthetic valve endocarditis. Four had aortic valve involvement and three had mitral involvement. All cases were diagnosed using blood culture, serology, and echocardiography.

Conclusion All were treated initially with antibiotics and valve replacement was done in five cases. Mortality was the outcome in two cases on conservative treatment and before surgery. Other five patients recovered after surgery.
Does the growth of military hard power back up the growth of monetary soft power via data-driven probabilistic optimal relations?
Authors: Chen Ray-Ming
Published: January 2022

The research of how economic growth and military expenses affect each other could be found in the literature, but a comprehensive quantitative study of the degree of interaction between military expenses and money currency is not fully investigated. In this study, we borrow the concepts of hard power and soft power and quantify these concepts by associating military hard power with military expenses over GDP and monetary soft power with growth rate of exchange rate over growth rate of broad money from 1961 to 2019. We study the causal relation between these two powers by mathematical and statistical approaches. We keep track of the time-series of Hausdorff distances between their empirical optimal relations and absolute linear relations and analyse their stability. The absolute linear relations serve as the benchmark for measuring the causality between military hard power and monetary soft power, while the empirical optimal relations reveal their actual interaction. Our result shows there is a clear causal relation that military hard power backs up monetary soft power, but not the other way around. This indicates that proper military spending over GDP would stabilise and promote the currency value of a country.
Phase-resolved visualization of radio-frequency standing waves in superconducting spiral resonator for metamaterial applications
Authors: Leha A. A. , Zhuravel A. P. , Karpov A. , Lukashenko A. V. , Ustinov A. V.
Published: January 2022

Superconducting microcircuits and metamaterials are promising candidates for use in new generation cryogenic electronics. Their functionality is largely justified by the macroscopic distribution of electromagnetic fields in arranged unit cells, rather than by the microscopic properties of composite materials. We present a new method for visualizing the spatial structure of penetrating microwaves with microscopic resolution in planar superconducting macroscopic resonators as the most important circuit-forming elements of modern microelectronics. This method uses a low-temperature laser scanning microscope that examines the phase (i.e., direction) and amplitude of local radio-frequency currents versus the two-dimensional coordinates of the superconducting resonant structure under test. Phase-sensitive contrast is achieved by synchronizing the intensity-modulated laser radiation with the resonant harmonics of the microwave signal passing through the sample. In this case, the laser-beam-induced loss in the illuminated area will strongly depend on the local phase difference between the RF carrier signal and the spatially temporal structure of the focused laser oscillation. This approach eliminates the hardware limitations of the existing technique of radio-frequency microscopy and brings the phase-sensitive demodulation mode to the level necessary for studying the physics of superconducting metamaterials. The advantage of the presented method over the previous method of RF laser scanning micros-copy is demonstrated by the example of the formation of standing waves in a spiral superconducting Archimedean resonator up to the 38th eigenmode resonance.
Second sound resonances in superfluid 3He–4He mixtures
Authors: Vikhtinskaya T. G. , Herashchenko N. O. , Nemchenko K. E.
Published: January 2022

The resonances occurring during oscillations of quartz tuning forks in superfluid helium and its mixtures are studied. Quartz tuning forks are used to study various properties of helium, and also as a precision temperature sensor. Experimental observations of resonance phenomena were carried out in a wide range of temperatures and pressures, but the results of observations have not yet been exhaustively described theoretically. In this work we consider the pressure, entropy, and velocities oscillations in order to determine the conditions under which oscillations of a solid wall excite the first and second sound in superfluid helium and sound in supercritical helium, and to calculate the contributions of these processes to the formation of resonances during oscillations of closed tuning forks. In particular, the experimentally observed excitation of standing waves of pressure and entropy oscillations by an oscillating closed tuning fork, the appearance and properties of resonances depending on the temperature and pressure of helium are considered.
Superconductivity in hole-doped germanium point contacts
Authors: Gamayunova N. V. , Kuzmiak M. , Szabó P. , Samuely P. , Naidyuk Yu. G.
Published: January 2022

We have observed superconductivity in heavy p-doped Ge by measuring of differential resistance dV/dI(V) of Ge–PtIr point contacts. The superconducting features disappear above 6 K or above 1 T, what can be taken as the critical temperature and the critical magnetic field, respectively. The observed dV/dI(V) spectrum with Andreev reflection like features was fitted within one-gap Blonder–Tinkham–Klapwijk model. The extracted superconducting gap demonstrates Bardeen–Cooper–Schrieffer-like behavior with 2Δ/kBTc = 10.5 ± 0.5 ratio, which is much higher than expected for conventional superconductors. Magnetic field suppresses Andreev reflection features, but the superconducting gap moderately decreases in magnetic field similarly as it was observed previously for the type II superconductors, including nickel borocarbide and iron-based superconductors. Curiously, we have not yet observed superconductivity in n-doped Ge with a similar dopant concentration.
A quantum key distribution testbed using a plug&play telecom-wavelength single-photon source
Authors: Gao Timm , Rickert Lucas , Urban Felix , Große Jan , Srocka Nicole , Rodt Sven , Musiał Anna , Żołnacz Kinga , Mergo Paweł , Dybka Kamil , Urbańczyk Wacław , Sȩk Grzegorz , Burger Sven , Reitzenstein Stephan , Heindel Tobias
Published: January 2022

Deterministic solid state quantum light sources are considered key building blocks for future communication networks. While several proof-of-principle experiments of quantum communication using such sources have been realized, most of them required large setups—often involving liquid helium infrastructure or bulky closed-cycle cryotechnology. In this work, we report on the first quantum key distribution (QKD) testbed using a compact benchtop quantum dot single-photon source operating at telecom wavelengths. The plug&play device emits single-photon pulses at O-band wavelengths (1321 nm) and is based on a directly fiber-pigtailed deterministically fabricated quantum dot device integrated into a compact Stirling cryocooler. The Stirling is housed in a 19 in. rack module including all accessories required for stand-alone operation. Implemented in a simple QKD testbed emulating the BB84 protocol with polarization coding, we achieve an multiphoton suppression of g(2)(0)=0.10±0.01 and a raw key rate of up to (4.72 ± 0.13) kHz using an external pump laser. In this setting, we further evaluate the performance of our source in terms of the quantum bit error ratios, secure key rates, and tolerable losses expected in full implementations of QKD while accounting for finite key size effects. Furthermore, we investigate the optimal settings for a two-dimensional temporal acceptance window applied on the receiver side, resulting in predicted tolerable losses up to 23.19 dB. Not least, we compare our results with previous proof-of-concept QKD experiments using quantum dot single-photon sources. Our study represents an important step forward in the development of fiber-based quantum-secured communication networks exploiting sub-Poissonian quantum light sources.
Enhanced laser-energy coupling with small-spot distributed phase plates (SG5-650) in OMEGA DT cryogenic target implosions
Authors: Theobald W. , Cao D. , Shah R. C. , Thomas C. A. , Igumenshchev I. V. , Bauer K. A. , Betti R. , Bonino M. J. , Campbell E. M. , Christopherson A. R. , Churnetski K. , Edgell D. H. , Forrest C. J. , Frenje J. A. , Gatu Johnson M. , Glebov V. Yu. , Goncharov V. N. , Gopalaswamy V. , Harding D. R. , Hu S. X. , Ivancic S. T. , Jacobs-Perkins D. W. , Janezic R. T. , Joshi T. , Knauer J. P. , Lees A. , Luo R. W. , Mannion O. M. , Marshall F. J. , Mohamed Z. L. , Morse S. F. B. , Patel D. , Peebles J. L. , Petrasso R. D. , Radha P. B. , Rinderknecht H. G. , Rosenberg M. J. , Sampat S. , Sangster T. C. , Shmayda W. T. , Shuldberg C. M. , Shvydky A. , Sorce C. , Stoeckl C. , Wittman M. D. , Regan S. P.
Published: January 2022

Cryogenic deuterium–tritium ice target implosions on OMEGA with new small-spot (SG5-650) distributed phase plates (DPPs) achieved an (11±4)% increase in energy coupling compared to implosions with larger-spot SG5-850 DPPs by decreasing the ratio of the laser spot diameter to the target diameter from 0.93 to 0.75. The SG5-650 DPPs provide a focus spot size of 674 μm, which is defined as the diameter that encircles 95% of the measured beam energy compared to 834 μm for the SG5-850, which are the standard DPPs in cryogenic target implosions on OMEGA. The hydrodynamic efficiency, defined as the ratio of the kinetic energy in the imploding shell to the laser energy, increased from 4.5% to 5.0% based on radiation-hydrodynamic calculations benchmarked to shell trajectory and bang-time measurements. The higher coupling came with a trade-off of an increased hot-electron production as well as increased hydrodynamic instabilities seeded by a larger mode-10 amplitude from the beam port geometry, both of which may have reduced the fusion neutron production and areal density.
Accuracy analysis of opacity models from transmission measurements in laser-produced plasmas
Authors: Kurzweil Y. , Polack-Schupper N.
Published: January 2022

The accuracy of opacity models, for warm-dense plasmas, is discussed by a comparison to nine transmission experiments in Al, Fe, FeNaF, Mo, Ho, and Au. The transmission measurements were performed in the NOVA, ASTERIX IV, and Shenguang-II laser facilities during the last three decades, where the achieved temperatures and densities were in the regime of 20–85 eV and 6–30 mg/cc, and the measured energy regimes were relevant to estimate the Rosseland and Planck opacities. A detailed error analysis of the measurements and accuracy analysis of the CRSTA and other models are presented.
The Madrid-2019 force field for electrolytes in water using TIP4P/2005 and scaled charges: Extension to the ions F−, Br−, I−, Rb+, and Cs+
Authors: Blazquez S. , Conde M. M. , Abascal J. L. F. , Vega C.
Published: January 2022

In this work, an extension of the Madrid-2019 force field is presented. We have added the cations Rb+ and Cs+ and the anions F−, Br−, and I−. These ions were the remaining alkaline and halogen ions, not previously considered in the Madrid-2019 force field. The force field, denoted as Madrid-2019-Extended, does not include polarizability and uses the TIP4P/2005 model of water and scaled charges for the ions. A charge of ±0.85e is assigned to monovalent ions. The force field developed provides an accurate description of aqueous solution densities over a wide range of concentrations up to the solubility limit of each salt studied. Good predictions of viscosity and diffusion coefficients are obtained for concentrations below 2 m. Structural properties obtained with this force field are also in reasonable agreement with the experiment. The number of contact ion pairs has been controlled to be low so as to avoid precipitation of the system at concentrations close to the experimental solubility limit. A comprehensive comparison of the performance for aqueous solutions of alkaline halides of force fields of electrolytes using scaled and integer charges is now possible. This comparison will help in the future to learn about the benefits and limitations of the use of scaled charges to describe electrolyte solutions.
Effect of electronegativity on electron surface scattering in thin metal layers
Authors: Jog Atharv , Milosevic Erik , Zheng Pengyuan , Gall Daniel
Published: January 2022

In situ transport measurements on 10-nm-thick epitaxial Cu(001), Co(001), and Rh(001) layers exhibit a characteristic increase in the sheet resistance ΔRs/Ro = 43%, 10%, and 4% when adding 4.0, 13.0, and 13.0 monolayers of Ti, respectively. Similarly, exposing these layers to 0.6 Torr O2 results in a 26%, 22%, and <5% increase in Rs. This suggests that adatoms on Cu and Co surfaces considerably disturb the surface potential, leading to diffuse electron scattering and a resulting resistance increase while these effects are negligible for Rh. A similarly small resistivity increase Δρ/ρ < 7% is measured during air exposure of 10-nm-thick epitaxial layers of electronegative metals including Ru, Rh, Ir, W, and Mo, while Δρ/ρ increases to 11%–36% for more electropositive metals including Cu, Ag, Co, Ni, and Nb. The Δρ for Ni, Co, and Nb is larger than what is expected for a complete transition from specular to diffuse surface scattering, indicating a breakdown of the semiclassical Fuchs–Sondheimer model, which needs to be replaced by a two-dimensional conductor description. The measured inverse correlation between electronegativity and Δρ/ρ suggests that the magnitude of the surface potential perturbation is the primary parameter affecting electron surface scattering in thin metal layers. More specifically, the charge transfer from electropositive metal surfaces to adatoms perturbs the surface potential and causes electron surface scattering and a resistance increase. Conversely, electronegative metals facilitate smooth surface potentials with specular electron reflection and a minimized resistance increase. They are, therefore, promising as conductors for highly scaled interconnect lines.
A cost-effective technology to improve power performance of nanoribbons GaN HEMTs
Authors: Soltani A. , Benbakhti B. , Gerbedoen J.-C. , Khediri A. , Maher H. , Salvestrini J.-P. , Ougazzaden A. , Bourzgui N. E. , Barkad H. A.
Published: January 2022

A cost-effective fabrication process is developed to improve the power performance of AlGaN/GaN High Electron Mobility Transistors (HEMTs). This process uses nitrogen ion (N+) implantation to form multiple parallel nanoribbons on AlGaN/GaN heterostructures, with a thin buffer layer (AlGaN/GaN NR-HEMTs). The stopping and range of ions in matter simulations of the N+ implantation combined with measured current-field characteristics reveal a good electrical isolation beneath the two-dimensional electron gas, resulting in substantial increase in the breakdown field of the NR-HEMTs, when compared to conventional AlGaN/GaN HEMTs. The fabricated AlGaN/GaN NR-HEMTs performed (i) an ON/OFF current ratio more than two orders of magnitude larger and (ii) a buffer leakage current more than one order of magnitude weaker than that of the conventional AlGaN/GaN HEMTs. The on-resistance, RON, and series resistance, RS, of AlGaN/GaN NR-HEMTs are both reduced by one order of magnitude when compared to those of the conventional AlGaN/GaN HEMTs. These have boosted the drive current density by up to 435%. Furthermore, we have found that the architecture of the AlGaN/GaN NR-HEMTs reduces the destructive impact of electron traps in the device. An optimized AlGaN/GaN NR-HEMT exhibited a better electrostatic integrity, a subthreshold slope of ∼210 mV/dec instead of 730 mV/dec for a conventional GaN HEMT. A higher linearity in the transconductance, gm, of NR-HEMTs is observed, twice of that of a conventional GaN HEMT. These results demonstrate the great interest of developed process technology of NR-HEMTs for high-power switching applications.
In situ proximity labeling identifies Lewy pathology molecular interactions in the human brain
Authors: Killinger Bryan A. , Marshall Lee L. , Chatterjee Diptaman , Chu Yaping , Bras Jose , Guerreiro Rita , Kordower Jeffrey H.
Published: January 2022

The intracellular misfolding and accumulation of alpha-synuclein into structures collectively called Lewy pathology (LP) is a central phenomenon for the pathogenesis of synucleinopathies, including Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). Understanding the molecular architecture of LP is crucial for understanding synucleinopathy disease origins and progression. Here we used a technique called biotinylation by antibody recognition (BAR) to label total (BAR-SYN1) and pathological alpha-synuclein (BAR-PSER129) in situ for subsequent mass spectrometry analysis. Results showed superior immunohistochemical detection of LP following the BAR-PSER129 protocol, particularly for fibers and punctate pathology within the striatum and cortex. Mass spectrometry analysis of BAR-PSER129–labeled LP identified 261 significantly enriched proteins in the synucleinopathy brain when compared to nonsynucleinopathy brains. In contrast, BAR-SYN1 did not differentiate between disease and nonsynucleinopathy brains. Pathway analysis of BAR-PSER129–enriched proteins revealed enrichment for 718 pathways; notably, the most significant KEGG pathway was PD, and Gene Ontology (GO) cellular compartments were the vesicle, extracellular vesicle, extracellular exosome, and extracellular organelle. Pathway clustering revealed several superpathways, including metabolism, mitochondria, lysosome, and intracellular vesicle transport. Validation of the BAR-PSER129–identified protein hemoglobin beta (HBB) by immunohistochemistry confirmed the interaction of HBB with PSER129 Lewy neurites and Lewy bodies. In summary, BAR can be used to enrich for LP from formalin-fixed human primary tissues, which allowed the determination of molecular signatures of LP. This technique has broad potential to help understand the phenomenon of LP in primary human tissue and animal models.
GABA transmission from mAL interneurons regulates aggression in
Drosophila
males
Authors: Sengupta Saheli , Chan Yick-Bun , Palavicino-Maggio Caroline B. , Kravitz Edward A.
Published: January 2022

Significance

Aggression is dependent on the sex of the conspecific in almost all animal species. But the neuronal basis of how sex-specific chemosensory signals regulate aggression is poorly understood. Using the fruit fly model of
Drosophila melanogaster
, we demonstrate that activation of a group of GABAergic central brain neurons, known to respond to sex-specific pheromonal stimuli, enhances aggression in dyadic male encounters. Inactivation of this neuronal group decreases aggression and increases the reciprocal social behavior of courtship. Our results can help trace the neural circuit from pheromone processing in the sensory neurons to behavior integration in the central brain and ultimately help understand how neurons encode the behavior of aggression.
Immunomagnetic microscopy of tumor tissues using quantum sensors in diamond
Authors: Chen Sanyou , Li Wanhe , Zheng Xiaohu , Yu Pei , Wang Pengfei , Sun Ziting , Xu Yao , Jiao Defeng , Ye Xiangyu , Cai Mingcheng , Shen Mengze , Wang Mengqi , Zhang Qi , Kong Fei , Wang Ya , He Jie , Wei Haiming , Shi Fazhan , Du Jiangfeng
Published: January 2022

Significance

Understanding cancer’s biomarker, microenvironment, and heterogeneity at the tissue level promises to improve cancer biology and clinical diagnosis and treatment. Many histological imaging techniques have been developed for this purpose. In this study, benefiting from the development of quantum sensing with nitrogen-vacancy (NV) centers in diamond, we proposed and experimentally realized micrometer-resolution magnetic imaging of tumor tissues in an NV-diamond magnetic microscope, magnetically imaging and quantifying cancer biomarkers. Moreover, we achieved the correlated magnetic and optical imaging in the same tissue section. The histological magnetometry exhibits excellent signal stability, negligible magnetic background, and accurate magnetic quantification. Our method thus opens the door to micrometer-resolution magnetic imaging of biological tissues and has the potential to influence research and histopathology of cancer.
Treatment of two infants with PIK3CA-related overgrowth spectrum by alpelisib
Authors: Morin Gabriel , Degrugillier-Chopinet Caroline , Vincent Marie , Fraissenon Antoine , Aubert Hélène , Chapelle Célia , Hoguin Clément , Dubos François , Catteau Benoit , Petit Florence , Mezel Aurélie , Domanski Olivia , Herbreteau Guillaume , Alesandrini Marie , Boddaert Nathalie , Boutry Nathalie , Broissand Christine , Han Tianxiang Kevin , Branle Fabrice , Sarnacki Sabine , Blanc Thomas , Guibaud Laurent , Canaud Guillaume
Published: January 2022

PIK3CA-related overgrowth spectrum (PROS) includes rare genetic conditions due to gain-of-function mutations in the PIK3CA gene. There is no approved medical therapy for patients with PROS, and alpelisib, an approved PIK3CA inhibitor in oncology, showed promising results in preclinical models and in patients. Here, we report for the first time the outcome of two infants with PROS having life-threatening conditions treated with alpelisib (25 mg) and monitored with pharmacokinetics. Patient 1 was an 8-mo-old girl with voluminous vascular malformation. Patient 2 was a 9-mo-old boy presenting with asymmetrical body overgrowth and right hemimegalencephaly with West syndrome. After 12 mo of follow-up, alpelisib treatment was associated with improvement in signs and symptoms, morphological lesions and vascular anomalies in the two patients. No adverse events were reported during the study. In this case series, pharmacological inhibition of PIK3CA with low-dose alpelisib was feasible and associated with clinical improvements, including a smaller size of associated complex tissue malformations and good tolerability.
Introduction to spectral line shape theory
Authors: Gomez T A , Nagayama T , Cho P B , Kilcrease D P , Fontes C J , Zammit M C
Published: January 2022

Spectral line-shape models are an important part of understanding high-energy-density (HED) plasmas. Models are needed for calculating opacity of materials and can serve as diagnostics for astrophysical and laboratory plasmas. However, much of the literature on line shapes is directed toward specialists. This perspective makes it difficult for non-specialists to enter the field. We have two broad goals with this topical review. First, we aim to give information so that others in HED physics may better understand the current field. This first goal may help guide future experiments to test different aspects of the theory. Second, we provide an introduction for those who might be interested in line-shape theory, and enough materials to be able to navigate the field and the literature. We give a high-level overview of line broadening process, as well as dive into the formalism, available methods, and approximations.
Mixed stochastic-deterministic time-dependent density functional theory: application to stopping power of warm dense carbon
Authors: White Alexander J , Collins Lee A , Nichols Katarina , Hu S X
Published: January 2022

Warm dense matter (WDM) describes an intermediate phase, between condensed matter and classical plasmas, found in natural and man-made systems. In a laboratory setting, WDM is often created dynamically. It is typically laser or pulse-power generated and can be difficult to characterize experimentally. Measuring the energy loss of high energy ions, caused by a WDM target, is both a promising diagnostic and of fundamental importance to inertial confinement fusion research. However, electron coupling, degeneracy, and quantum effects limit the accuracy of easily calculable kinetic models for stopping power, while high temperatures make the traditional tools of condensed matter, e.g. time-dependent density functional theory (TD-DFT), often intractable. We have developed a mixed stochastic-deterministic approach to TD-DFT which provides more efficient computation while maintaining the required precision for model discrimination. Recently, this approach showed significant improvement compared to models when compared to experimental energy loss measurements in WDM carbon. Here, we describe this approach and demonstrate its application to warm dense carbon stopping across a range of projectile velocities. We compare direct stopping-power calculation to approaches based on combining homogeneous electron gas response with bound electrons, with parameters extracted from our TD-DFT calculations.
Quantum transport and potential of topological states for thermoelectricity in Bi2Te3 thin films
Authors: Ngabonziza Prosper
Published: January 2022

This paper reviews recent developments in quantum transport and it presents current efforts to explore the contribution of topological insulator boundary states to thermoelectricity in Bi2Te3 thin films. Although Bi2Te3 has been used as a thermoelectric material for many years, it is only recently that thin films of this material have been synthesized as 3D topological insulators with interesting physics and potential applications related to topologically protected surface states. A major bottleneck in Bi2Te3 thin films has been eliminating its bulk conductivity while increasing its crystal quality. The ability to grow epitaxial films with high crystal quality and to fabricate sophisticated Bi2Te3-based devices is attractive for implementing a variety of topological quantum devices and exploring the potential of topological states to improve thermoelectric properties. Special emphasis is laid on preparing low-defect-density Bi2Te3 epitaxial films, gate-tuning of normal-state transport and Josephson supercurrent in topological insulator/superconductor hybrid devices. Prospective quantum transport experiments on Bi2Te3 thin-film devices are discussed as well. Finally, an overview of current progress on the contribution of topological insulator boundary states to thermoelectricity is presented. Future explorations to reveal the potential of topological states for improving thermoelectric properties of Bi2Te3 films and realizing high-performance thermoelectric devices are discussed.
First-principles study on CO oxidation on CuO(111) surface prefers the Eley−Rideal or Langmuir−Hinshelwood pathway
Authors: Lin Long , Shi Pei , Yao Linwei , Xie Kun , Tao Hualong , Zhang Zhanying , Wang Yanfang
Published: January 2022

Using the first-principles approach, we investigated the electronic and chemical properties of cupric oxide CuO (110) and CuO (111) and substantiated their catalytic activity toward CO oxidation. It is found that CuO (111) surface is more stable than the CuO (110) surface. We firstly study that adsorption of CO and O2 on perfect, oxygen vacancies and Cu-anchored CuO (111) surface. It is found that adsorption of CO and O2 molecules are chemical. Then we selected the most stable adsorption structure of CO/O2 to investigated the CO oxidation mechanism on different surface, here we choose to study the Langmuir–Hinshelwood (LH) mechanism and Eley–Rideal (ER) mechanism. The results show that perfect and Ovacancy CuO (111) surface is more inclined to LH mechanism, while the Cu-anchored CuO (111) surface is more inclined to ER mechanism. The results show that CuO catalyst is very effective for CO oxidation. Our work provides a deep understanding for the search of economical and reasonable CO oxidation catalysts.
Appearance of Keplerian discs orbiting on both sides of reflection-symmetric wormholes
Authors: Schee Jan , Stuchlík Zdeněk
Published: January 2022

We construct optical appearance and profiled spectral lines of Keplerian discs with inner edge at the innermost circular geodesic located on both sides of reflection-symmetric Simpson-Visser wormholes, in dependence on their parameter and inclination angle of distant observers. We demonstrate significant differences in appearance of the discs on the our side and the other side of the Simpson-Visser wormholes. Large part of the other-side disc is always in dark region of the image of the disc orbiting on the our side, enabling thus a simple distinguishing in observations. The profiled spectral lines generated by the disc on the other side (our side) demonstrate strong (weak) dependence on the spacetime parameter, and weak (strong) dependence on the inclination angle; they have also different shape, giving thus other clues to clearly distinguish in observations reflection-symmetric wormholes as alternatives to black holes.
Neurological state changes indicative of ADHD in children learned via EEG-based LSTM networks
Authors: Chang Yang , Stevenson Cory , Chen I-Chun , Lin Dar-Shong , Ko Li-Wei
Published: January 2022

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that pervasively interferes with the lives of individuals starting in childhood. Objective. To address the subjectivity of current diagnostic approaches, many studies have been dedicated to efforts to identify the differences between ADHD and neurotypical (NT) individuals using electroencephalography (EEG) and continuous performance tests (CPT). Approach. In this study, we proposed EEG-based long short-term memory (LSTM) networks that utilize deep learning techniques with learning the cognitive state transition to discriminate between ADHD and NT children via EEG signal processing. A total of 30 neurotypical children and 30 ADHD children participated in CPT tests while being monitored with EEG. Several architectures of deep and machine learning were applied to three EEG data segments including resting state, cognitive execution, and a period containing a fusion of those. Main results. The experimental results indicated that EEG-based LSTM networks produced the best performance with an average accuracy of 90.50 ± 0.81% in comparison with the deep neural networks, the convolutional neural networks, and the support vector machines with learning the cognitive state transition of EEG data. Novel observations of individual neural markers showed that the beta power activity of the O1 and O2 sites contributed the most to the classifications, subjects exhibited decreased beta power in the ADHD group, and had larger decreases during cognitive execution. Significance. These findings showed that the proposed EEG-based LSTM networks are capable of extracting the varied temporal characteristics of high-resolution electrophysiological signals to differentiate between ADHD and NT children, and brought a new insight to facilitate the diagnosis of ADHD. The registration numbers of the institutional review boards are 16MMHIS021 and EC1070401-F.
Light outputs of yttrium doped BaF_2 crystals irradiated with neutrons
Authors: Baranov V. , Davydov Yu.I. , Vasilyev I.I.
Published: January 2022

The fast luminescence component of barium fluoride (BaF_2)
crystals with a subnanosecond decay time can find wide application
in particle physics and nuclear physics. However, the slow
luminescence component with the 630 ns decay time could cause
pile-up signals at a high rate environment. Doping of BaF2
crystals with rare earth elements suppresses the slow emission
component, but at the same time the radiation hardness of the
crystals deteriorates. This work presents the results of studying
crystal samples, both pure BaF2 and those doped with yttrium in a
proportion of 1 at.%Y, 3 at.%Y and 5 at.%Y, irradiated with a
fast neutron fluence of about 2.3×1014 n/cm2. Their
light output and decay kinetics were measured before and after
irradiation. It is found that the light output loss of a pure
BaF2 crystal after irradiation is about 7%, and the light output
loss of yttrium doped samples after irradiation is about two times
higher. The measurement results demonstrate that after irradiation
the fast component of each sample has a relative light output loss
2–3% larger than the slow one.
Bibliometric survey and network analysis of biomimetics and nature inspiration in engineering science
Authors: Gerbaud Vincent , Leiser Hugues , Beaugrand Johnny , Cathala Bernard , Molina-Jouve Carole , Gue Anne Marie
Published: January 2022

The field encompassing biomimetics, bioinspiration and nature inspiration in engineering science is growing steadily, pushed by exogenous factors like the search for potentially sustainable engineering solutions that might already exist in nature. With the help of information provided by a bibliometric database and further processed with a dynamic network and semantic analysis tool, we provide insight at two scales into the corpus of nature-inspired engineering field and its dynamics. At the macroscale, the Web of Science® (WoS) categories, countries and institutions are ranked and ordered by thematic clusters and country networks, highlighting the leading countries and institutions and how they focus on specific topics. Such an insight provides an overview at the macroscale that can be valuable to orient scientific strategy at the country level. At the mesoscale, where science is incarnated by collaborative networks of authors and institutions that run across countries, we identify six semantic clusters and subclusters within them, and their dynamics. We also pinpoint leading academic collaborative networks and their activity in relation to the six semantic clusters. Trends and prospective are also discussed. Typically, one observes that the field is becoming mature since, starting by imitating nature, it proceeded with mimicking more complex natural structures and functions and now it investigates ways used in nature in response to changes in the environment and implements them in innovative and adaptive artefacts. The sophistication of devices, methods and tools has been increasing over the years as well as their functionalities and adaptability, whereas the size of devices has decreased at the same time.
Systematic investigation of spectral characteristics and sensing characteristics of microfiber knot resonator
Authors: Xia Feng , Liu Bo , Ying Yu
Published: January 2022

In this work, we systematically study the transmission spectral characteristics of the microfiber knot resonator (MKR) both in simulation and in an experiment. The transmission spectrum shows several possible phenomena, including dominating resonance, dominating interference, the coexistence of resonance and interference with different intensity ratios, and resonance with Vernier effect. The transmission spectra with various shapes are obtained in simulation by adjusting parameters like fractional coupling intensity loss, intensity coupling ratio, and propagation constants of different modes. The relationship between the transmission spectrum and the size of the resonant ring is studied by reducing the diameter of the resonant ring and analyzing the corresponding transmission spectrum. The performance of a polydimethylsiloxane-coated MKR in refractive index and temperature measurement is also investigated, and the responses of the transmission spectrum, the extracted interference spectrum, the extracted resonance spectrum, the extracted envelope spectrum of Vernier effect are all analyzed, indicating that these spectra have similar responses to the variation of refractive index or temperature. Linear fit indicates that the sensitivities of the transmission spectrum to refractive index and temperature are about 1264.09 nm RIU−1 and −2.60 nm/°C, respectively. This systematic and comprehensive study will provide a helpful guideline for understanding, analyzing and designing MKR-based devices with desired spectral characteristics to meet different application requirements.
Bottom-up approach for traceable calibration of tip geometry of stylus profilometer
Authors: Dai Gaoliang , Hu Xiukun , Degenhardt Johannes
Published: January 2022

A novel approach for accurate and traceable calibration of stylus tip geometry is introduced in the paper. The approach consists of several steps. Firstly, the geometry of an AFM tip is calibrated to a kind of line width standard whose geometry is traceably calibrated to the lattice constant of crystal silicon. Then, the stylus tip to be calibrated is measured by the calibrated AFM tip in an AFM, thus its tip geometry can be accurately determined after the contribution of the AFM tip geometry being corrected from the measured AFM image. After being calibrated, the stylus tip can be applied in measurements of vast microstructures and surfaces, where the measurement results can be in turn corrected using the characterized stylus tip geometry. In such a way, the stylus tip geometry and its measurement results can be finally traceable to the lattice constant of silicon, using this bottom-up approach. Detailed experimental examples are illustrated. For a stylus type RFTHB-50 studied in this paper, its tip radius is measured as 1.727 μm with a standard deviation of 0.007 μm. It is significantly smaller than its nominal value of 2 μm, indicating the need of the calibration. The application of calibrated stylus tip in measurements of microspheres is demonstrated. Compared to conventional tip characterization methods based on tip characterizers the proposed method has advantages of (i) no risk of damaging sharp edges of tip characterizers, (ii) capable of directly characterizing the 3D geometry of stylus tip, (iii) high accuracy.
Optimization of Burnishing process by Taguchi method for surface enhancement of EN31 steel
Authors: Varpe Nitin Jalindar , Gurnani Umesh , Hamilton Anurag
Published: January 2022

Surface finish plays important role in service characteristics of an element, such as corrosion resistance, wear resistance and fatigue life. This leads to investigate surface finishing processes like polishing, buffing, lapping, burnishing etc. Burnishing is well known, effective and efficient super finishing technique which involves surface layers plastic deformation by cold working to refine surface texture and improve service life of component. Current work focuses on investigation of ball burnishing process and optimization of it on EN31 steel. Taguchi method is implemented for determination of best possible process parameters combination to decrease surface roughness and increase hardness of EN31 steel specimens. After burnishing surface roughness decreases from 0.446 to 0.089 μm and hardness increases from 179.5 to 266.5 Hv. Burnishing speed and feed are remarkable factors for decreasing surface roughness, whereas no. of tool passes and applied force are crucial for increasing hardness, according to optimization results. Validation tests are carried out with ideal levels of process parameters, confirming that the process of ball burnishing has improved the surface finish and hardness of EN31 steel.
Microstructure, mechanical and wear behavior of LM24/SiC/MoS2 hybrid composites produced via liquid metallurgy process
Authors: Hariharan S R , Mahendran S , Meignanamoorthy M , Ravichandran M
Published: January 2022

Silicon carbide (SiC) and Molybdenum disulphide (MoS2) has been expected broad contemplation is a potential strengthening particulate for metal matrix composites (MMCs) to enhance the mechanical and wear behaviors. The purpose of this study is to process and investigate the mechanical characteristics of LM 24/SiC/MoS2 composites. These composites were fabricated via the stir casting process from the prepared arrangements of LM 24/SiC/MoS2 with various weight proportions. The following proportions are pure LM 24, LM24-3wt%SiC-1wt%MoS2, LM24-6wt%SiC-1wt%MoS2 and LM24-9wtSiC-1wt%MoS2. The scanning electron microscope (SEM) utilized to inspect the micrographs on processed composites. The SEM micrographs interpret identical dispersion of SiC with LM 24. The influence of SiC weight percentage on the physical properties like density, relative density & porosity and mechanical properties like tensile, compression, hardness, impact and flexural strength and tribological behavior were investigated. The processed LM24-9wt%SiC-1wt%MoS2 composites compose the enhanced mechanical properties. The wear performance was studied throughout the pin on disc device with various wear process parameters. These parameters are load, Sliding velocity and distance. Finally, these parameters are framed via the L16 orthogonal array and to attain the minimum wear rate and coefficient of friction from the optimal process parameters by Grey Relational Analysis (GRA). The optimal parameters for wear rate and coefficient of friction are LM24-9wt%SiC-1wt%MoS2 and followed by the wear parameters namely load 15N, sliding velocity 2 m s−1 and sliding distance 1600 m, respectively. The ANOVA outcomes uncovers that the load is the most significant parameter for wear rate and coefficient of friction.
Binder-free fabricated CuFeS2 electrodes for supercapacitor applications
Authors: Nsude Hope Ebere , Obodo Raphael M , Nsude Kingsley U , Ikhioya Lucky I , Asogwa Paul U , Osuji R U , Maaza M , Ezema Fabian I
Published: January 2022

Copper iron sulfide (CFS) (chalcopyrite) thin-film electrodes have been synthesized for energy storage applications using the SILAR method without the use of a binder. The film’s structural as well as the morphological and electrochemical characteristics were studied to check the effect of varying deposition cycles. The x-ray diffraction (XRD) test reveals a crystalline tetragonal CuFeS2 (chalcopyrite) with a decreasing peak as the deposition cycle progresses. The micrographs of the films reveal a spherical but fleecy-like shape with particle aggregation at higher deposition cycles. The bandgap increased slightly towards higher cycles and is in the range of 1.15 to 1.22 eV. The CFS electrodes were evaluated in a three-electrode arrangement for supercapacitive application in a 2.0 M KOH electrolyte. The CFS electrodes function admirably. The greatest specific capacitance recorded was 537 F g−1 at 10 mV s−1 with capacitance retention of 93.5%. This is for CFS electrode deposited at 10 cycles; hence it has the greatest performance. This paper describes a simple, inexpensive, and repeatable method for fabricating electrodes for supercapacitors.