bluuebunny/crossref_metadata_2025 huggingface dataset:
Ionised gas kinematics in MaNGA AGN
Authors: Deconto-Machado A. , Riffel R. A. , Ilha G. S. , Rembold S. B. , Storchi-Bergmann T. , Riffel R. , Schimoia J. S. , Schneider D. P. , Bizyaev D. , Feng S. , Wylezalek D. , da Costa L. N. , do Nascimento J. C. , Maia M. A. G.
Published: January 2022

Context.Feedback from active galactic nuclei (AGNs) in general seems to play an important role in the evolution of galaxies, although the impact of AGN winds on their host galaxies is still unknown in the absence of a detailed analysis.

Aims.We aim to analyse the kinematics of a sample of 170 AGN host galaxies as compared to those of a matched control sample of non-active galaxies from the MaNGA survey in order to characterise and estimate the extents of the narrow-line region (NLR) and of the kinematically disturbed region (KDR) by the AGN.

Methods.We defined the observed NLR radius (rNLR, o) as the farthest distance from the nucleus within which both [O III]/Hβand [N II]/Hαratios fall in the AGN region of the BPT diagram, and the Hαequivalent width was required to be larger than 3.0 Å. The extent of the KDR (rKDR, o) is defined as the distance from the nucleus within which the AGN host galaxies show a more disturbed gas kinematics than the control galaxies.

Results.The AGN [O III]λ5007 luminosity ranges from 1039to 1041erg s−1, and the kinematics derived from the [O III] line profiles reveal that, on average, the most luminous AGNs (L[O III] > 3.8 × 1040erg s−1) possess higher residual differences between the gaseous and stellar velocities and velocitie dispersions than their control galaxies in all the radial bins. Spatially resolved NLRs and KDRs were found in 55 and 46 AGN host galaxies, with corrected radii 0.2 < rKDR, c < 2.3 kpc and 0.4 < rNLR, c < 10.1 kpc and a relation between the two given by logrKDR, c = (0.53 ± 0.12) logrNLR, c + (1.07 ± 0.22), respectively. On average, the extension of the KDR corresponds to about 30% of that of the NLR. Assuming that the KDR is due to an AGN outflow, we have estimated ionised gas mass outflow rates that range between 10−5and ∼1M⊙yr−1, and kinetic powers that range from 1034to 1040erg s−1.

Conclusions.Comparing the power of the AGN ionised outflows with the AGN luminosities, they are always below the 0.05LAGNmodel threshold for having an important feedback effect on their respective host galaxies. The mass outflow rates (and power) of our AGN sample correlate with their luminosities, populating the lowest AGN luminosity range of the correlations previously found for more powerful sources.
CaRM: Exploring the chromatic Rossiter-McLaughlin effect
Authors: Cristo E. , Santos N. C. , Demangeon O. , Martins J. H. C. , Figueira P. , Casasayas-Barris N. , Zapatero Osorio M. R. , Borsa F. , Sousa S. G. , Oshagh M. , Micela G. , Tabernero H. M. , Seidel J. V. , Cristiani S. , Pepe F. , Rebolo R. , Adibekyan V. , Allart R. , Alibert Y. , Azevedo Silva T. , Bourrier V. , Cabral A. , Esparza-Borges E. , González Hernández J. I. , Lillo-Box J. , Lo Curto G. , Lovis C. , Manescau A. , Di Marcantonio P. , Martins C. J. A. P. , Mégevand D. , Mehner A. , Nunes N. J. , Palle E. , Sozzetti A. , Suárez Mascareño A. , Udry S.
Published: January 2022

Aims.In this paper we introduceCaRM, a semi-automatic code for the retrieval of broadband transmission spectra of transiting planets through the chromatic Rossiter-McLaughlin method. We applied it to HARPS and ESPRESSO observations of two exoplanets to retrieve the transmission spectrum and we analyze its fitting transmission models.

Methods.We used the strong radius dependence of the Rossiter-McLaughlin (RM) effect amplitude, caused by planetary companions, to measure the apparent radius change caused by the exoplanet atmosphere. In order to retrieve the transmission spectrum, the radial velocities, which were computed over wavelength bins that encompass several spectral orders, were used to simultaneously fit the Keplerian motion and the RM effect. From this, the radius ratio was computed as a function of the wavelength, which allows one to retrieve the low-resolution broadband transmission spectrum of a given exoplanet.CaRMoffers the possibility to use two Rossiter-McLaughlin models taken fromARoMEandPyAstronomy, associated with a Keplerian function to fit radial velocities during transit observations automatically. Furthermore it offers the possibility to use some methods that could, in theory, mitigate the effect of perturbation in the radial velocities during transits.

Results.We appliedCaRMto recover the transmission spectrum of HD 189733b and WASP-127b, with HARPS and ESPRESSO data, respectively. Our results for HD 189733b suggest that the blue part of the spectrum is dominated by Rayleigh scattering, which is compatible with former studies. The analysis of WASP-127b shows a flat transmission spectrum.

Conclusions.TheCaRMcode allows one to retrieve the transmission spectrum of a given exoplanet using minimal user interaction. We demonstrate that it allows one to compute the low-resolution broadband transmission spectra of exoplanets observed using high-resolution spectrographs such as HARPS and ESPRESSO.
Management einer persistierenden Kolitis nach erfolgreicher Immuntherapie eines nicht-kleinzelligen Karzinoms der Lunge
Authors: Zellweger Matthias , Rogler Gerhard , Komminoth Paul , Werth Lucas , Breidert Matthias
Published: January 2022

Zusammenfasssung

Immuncheckpoint-Inhibitoren haben als neue Generation von Medikamenten in der Anti-Tumortherapie bemerkenswerte Wirksamkeit gezeigt. Die unspezifische Aktivierung des Immunsystems führt jedoch zu einer Reihe von unerwünschten Nebenwirkungen, sog. immune-related adverse events (irAEs), inklusive des Auftretens von Diarrhoe und Kolitis bei etwa einem Drittel der behandelten Patienten.

Endoskopisch und histologisch gibt es weitreichende Überlappungen der immunvermittelten Kolitis mit der klassischen CED, was eine Unterscheidung erschwert.

Therapeutisch kommen bei Grad-3- (schwere) bis Grad-4-Kolitiden (lebensbedrohlich) neben dem Abbruch der ICI-Therapie hochdosiert Glukokortikoide zum Einsatz. Steroidrefraktäre Fälle (bis 42%) profitieren vom TNF-Hemmer Infliximab. Vedolizumab stellt, analog bei chronisch entzündlichen Darmerkrankungen, die Zweitlinientherapie bei Infliximab-refraktären Fällen dar. Zur Wirksamkeit von Tofacitinib bei therapierefraktären Fällen existieren bislang nur wenige Daten.

Wir beschreiben den Fall und das Therapiemanagement einer schweren und andauernden immunvermittelten Kolitis nach erfolgreicher Immunochemotherapie mit Pembrolizumab bei einem 80-jährigen Mann mit einem metastasierten, nicht kleinzelligen Karzinom der Lunge und vorbestehender Colitis indeterminata (colitis unclassified) sowie weiteren Komorbiditäten.
Contrast-enhanced ultrasonography (CEUS) reveals active bleeding into an abdominal hematoma in a patient with ongoing subcutaneous injections
Authors: Klenk Christopher , Clevert Dirk-André
Published: January 2022

A 95-year-old woman with metastasizing bronchial carcinoma presents with left inguinal pain. The referring physician would like to exclude an inguinal hernia and a deep vein thrombosis due to her precondition of essential thrombocythemia. Conventional ultrasound excluded the presence of a deep vein thrombosis yet showed a 6 cm × 5 cm hematoma distal of the left m. rectus abdominis. The subsequently performed color Doppler examination excluded a pseudoaneurysm but could not preclude active bleeding. Eventually, CEUS showed contrast-pooling within the hematoma as a sign of active extravasation, suggesting ongoing bleeding.
Anticoagulation in Pediatric Patients
Authors: Male Christoph
Published: January 2022

Special aspects of anticoagulation in children include the different epidemiology of thrombosis, developmental changes in the coagulation system, age-dependent pharmacokinetics of anticoagulants, risk of bleeding, and practical hurdles to anticoagulation. The classical anticoagulants so far used in children have several limitations, resulting in the need for regular monitoring. The pharmacological properties of direct oral anticoagulants (DOACs) and the special challenges of anticoagulation in children make the DOACs particularly attractive for children. All DOACs have pediatric development programs, targeting various indications for prevention and treatment of thrombosis. Child-appropriate formulations have been developed, age-specific dosing information generated, and safety and efficacy evaluated in ongoing phase 3 trials. Rivaroxaban and dabigatran have already been authorized for children for treatment of acute venous thrombosis and for extended secondary prevention. Their safety and efficacy have been demonstrated comparable to that of standard-of-care anticoagulants, without need for monitoring. Further studies are ongoing, which are expected to lead to pediatric authorizations of DOACs for primary venous thromboembolic event prevention in some high-risk settings. More real-life data will be necessary from postmarketing studies and registries to complement the evidence base for DOAC use in children, particularly in the youngest age groups and special disease populations.
In silico
Investigation of Lon Protease as a Promising
Therapeutic Target
Authors: Asadollahi Parisa , Pakzad Iraj , Ghafourian Sobhan , Kazemian Hossein , Fatahi Roohollah , Sadeghifard Nourkhoda , Kalani Behrooz Sadeghi
Published: January 2022

Considering the widespread occurrence of antibiotic resistance, the need for new
therapeutic strategies is inevitable. Bacterial proteases are a broad set of
enzymes that play a vital role in cell survival, stress response, and
pathogenicity. This in silico study was aimed to focus on the crucial
role of Lon protease in the regulation of toxin-antitoxin systems in E.
coli and to design inhibitory peptides against the action of this
protease. With the help of relevant servers and softwares, the communication
network, the evolutionary history, and the interaction of Lon with the
corresponding antitoxins were examined, following which the inhibitory peptides
were designed against these interactions. The results showed that Lon protease
plays a central role in the control of these systems and is a conserved protein,
especially among the Enterobacteriaceae family. The docking results of the
designed peptides with the Lon protease were significant. This study showed that
Lon protease may have the characteristics of a new therapeutic target.
Evaluation of the Genotoxic Potential of the Selective COX-2
Inhibitor Enflicoxib in a Battery of in vitro and in vivo
Genotoxicity Assays
Authors: Guzmán Antonio , Homedes Josep , Salichs Marta
Published: January 2022

Aim Enflicoxib, a selective COX-2 inhibitor approved for the treatment of
pain and inflammation associated with osteoarthritis in dogs
(Daxocox® [Ecuphar/Animalcare Group]) was
assessed for its genotoxic potential in a battery of in vitro and in
vivo genotoxicity assays. These comprised a bacterial reverse mutation
assay (Ames test), an in vitro human lymphocyte chromosome aberration
assay and an in vivo mouse bone marrow micronucleus assay.

Methods Relevant vehicle and positive control cultures and animals were
included in all assays. In the Ames test, enflicoxib was tested at
concentrations of up to 5000 μg/plate. Signs of
cytotoxicity were observed at the highest tested concentrations for several of
the bacterial strains, both in absence and presence of S9. In human lymphocytes,
enflicoxib was assessed for the induction of chromosomal aberrations when
exposed at concentrations of up to 62.5 (3 hours) and
29.6 µg/mL (20 hours) in the absence of S9, and
up to 66.7 µg/mL (3 hours) in presence of S9.
Signs of cell toxicity, evidenced as a decrease in the mitotic index, were
observed at these concentrations. In the mouse micronucleus assay, enflicoxib
dose levels of up to 2000 mg/kg were administered (single dose)
to male and female animals, and bone marrow samples were taken 24 and
48 hours (high-dose animals only) after administration.

Results Enflicoxib was shown to lack genotoxic activity in the conducted
assays.

Conclusions The administration of enflicoxib as a therapeutic analgesic
agent would not pose a genotoxic risk to animals or humans.
Mechanochemical Synthesis of 2,5-Disubstituted 1,3,4-Oxadiazoles Mediated by PPh3-TCCA
Authors: Pattarawarapan Mookda , Yamano Dolnapa , Wiriya Nittaya , Phakhodee Wong , Wet-osot Sirawit
Published: January 2022

Mechanochemical synthesis of 2,5-disubstituted 1,3,4-oxadiazoles was developed as an environmentally benign alternative to conventional solvent-based methods. In the presence of triphenylphosphine and trichloroisocyanuric acid, N-acylbenzotriazoles condense with acylhydrazides leading to oxadiazoles derivatives in good to excellent yields within minutes. The approach circumvents the need for strictly anhydrous conditions, external heating, long reaction times, as well as tedious multistep procedures. A range of substrates with reactive functionalities was also well tolerated.
New Insights into the Prevention of Hospital-Acquired Pneumonia/Ventilator-Associated Pneumonia Caused by Viruses
Authors: Klompas Michael
Published: January 2022

A fifth or more of hospital-acquired pneumonias may be attributable to respiratory viruses. The SARS-CoV-2 pandemic has clearly demonstrated the potential morbidity and mortality of respiratory viruses and the constant threat of nosocomial transmission and hospital-based clusters. Data from before the pandemic suggest the same can be true of influenza, respiratory syncytial virus, and other respiratory viruses. The pandemic has also helped clarify the primary mechanisms and risk factors for viral transmission. Respiratory viruses are primarily transmitted by respiratory aerosols that are routinely emitted when people exhale, talk, and cough. Labored breathing and coughing increase aerosol generation to a much greater extent than intubation, extubation, positive pressure ventilation, and other so-called aerosol-generating procedures. Transmission risk is proportional to the amount of viral exposure. Most transmissions take place over short distances because respiratory emissions are densest immediately adjacent to the source but then rapidly dilute and diffuse with distance leading to less viral exposure. The primary risk factors for transmission then are high viral loads, proximity, sustained exposure, and poor ventilation as these all increase net viral exposure. Poor ventilation increases the risk of long-distance transmission by allowing aerosol-borne viruses to accumulate over time leading to higher levels of exposure throughout an enclosed space. Surgical and procedural masks reduce viral exposure but do not eradicate it and thus lower but do not eliminate transmission risk. Most hospital-based clusters have been attributed to delayed diagnoses, transmission between roommates, and staff-to-patient infections. Strategies to prevent nosocomial respiratory viral infections include testing all patients upon admission, preventing healthcare providers from working while sick, assuring adequate ventilation, universal masking, and vaccinating both patients and healthcare workers.
Combined EUS LAMS and Percutaneous Fully Covered SEMS-Guided Direct Endoscopic Necrosectomy (e-DEN + p-DEN) for Walled-Off Pancreatic Necrosis with Paracolic Extension
Authors: Gandhi Ashish , Borkar Mangesh , Bapaye Harsh , Pujari Rajendra , Bapaye Amol
Published: January 2022

Management of infected lesser sac walled-off pancreatic necrosis (WOPN) is technically challenging and involves endoscopic ultrasound (EUS)-guided transmural drainage using either lumen-apposing metal stent (LAMS) or multiple plastic stents as the standard approach. A step-up approach—drainage followed by additional direct endoscopic necrosectomy (DEN) whenever required—has been a standard recommendation. Collections extending to the paracolic gutter are difficult to manage endoscopically and often require additional surgical intervention. In this video case, we describe a combined approach using EUS-guided LAMS and percutaneous fully covered self-expandable metal stent-guided DEN (e-DEN + p-DEN) for successful management of an infected lesser sac WOPN with paracolic extension.
Composition of Piperine with Enteric-Coated Chitosan Microspheres Enhances the Transepithelial Permeation of Curcumin in Sheep Intestinal Mucosa and Caco-2 Cells
Authors: Thomas Githa , Koland Marina
Published: January 2022

Objectives The purpose of this study was to investigate the efficacy of enteric-coated chitosan microspheres with herbal bioenhancer, piperine, as a suitable composition for improving the permeation of curcumin through biological membranes using suitable ex vivo models.

Material and Methods Chitosan microspheres of curcumin and piperine were prepared by an emulsion cross-linking method using glutaraldehydes the cross-linking agent and characterized for size, shape, entrapment efficiency, mucoadhesion, and in vitro release. The effect of piperine on the permeation of curcumin through excised sheep intestinal mucosa and Caco-2-cell monolayer was investigated.

Statistical Analysis The data from permeation studies were analyzed by Student's t-test using Statistical Package for the Social Sciences (SPSS) software (SPSS, Chicago, IL, United States) with p-values <0.05 indicating statistical significance.

Results The formulations showed mucoadhesion for a period of more than 6 hours which was influenced by the chitosan content. The rate of drug release of uncoated formulation followed first-order kinetics, and the mechanism of release was non-Fickian transport. Optimized formulation was coated with a pH-sensitive polymer, Eudragit S-100, by a solvent evaporation technique in different concentrations and evaluated for ex vivo permeation through sheep intestinal mucosa and Caco-2-cell monolayer. Scanning electron microscopy images of the optimized coated formulation showed spherical particles with smooth surfaces. The calculated permeation flux and permeability coefficient of curcumin from microspheres were at least 20% greater in the presence of piperine through the intestinal mucosa and 30% through the Caco-2-cell monolayer model. The permeability coefficient of curcumin from microspheres with piperine was 1.93 × 10 to 5 cm/sec and significantly greater (p < 0.05) than that of microspheres devoid of piperine and from aqueous dispersion (p < 0.005).

Conclusion The study confirmed the contribution of piperine and mucoadhesive microspheres toward improved permeation of curcumin through biological membranes, thereby providing an approach that has the potential of increasing transport through intestinal epithelial cells and possibly enhancing the oral bioavailability of this drug.
Psychological Impact Assessment in Patients with Noncommunicable Diseases during COVID-19 Pandemic through Validated Fear of COVID-19 scale: A Cross-Sectional Online Survey
Authors: Ponnam Hima B. , Akondi Butchi R. , Jagadabhi Santosh K. , Koppula Divya T. , Konduru Shanmukha P.
Published: January 2022

Background The novel coronavirus disease 2019 (COVID-19) pandemic has created immense panic globally with its advent in December 2019 and now showing readvent with its camouflage of different dangerous mutant strains. Its psychological repercussions on the community are very disastrous and immeasurable. At this juncture, the most vulnerable group are the patients of Noncommunicable diseases (NCDs) who are the most sufferers due to the impact caused by the anxiety and fear of COVID-19 apart from its high rate of infectivity. In this context, an online survey to assess the levels of anxiety and fear of COVID-19 in patients with lifestyle diseases has been taken up.

Methods This was an online cross-sectional survey using the Fear of COVID-19 Scale (FCV-19S) to assess the levels of anxiety and fear in patients with NCDs. The survey was made available for both genders and an age group of 30 years and above in India.

Results and Discussion A total of 627 participants participated in this online survey. The Indian residents with NCDS )Noncommunicable diseases) were found to suffer from significantly increased levels of anxiety and fear of COVID-19 and almost 60.4% of the participants were found to acquire these lifestyle diseases as diabetes and hypertension during this recent COVID-19 times.

Conclusion This survey shows the real-time psychological impact of COVID-19 which has a disastrous effect upon the community especially on the patients with NCDs who are the most vulnerable group. The study findings corroborate with the recent studies conducted on NCDs.
A Study of Clinical and Serological Correlation of Positive Direct Antiglobulin Test in Blood Bank at a Tertiary Care Center
Authors: Kerkar Alisha Suresh , Bhagwat Swarupa Nikhil , Sharma Jayashree Harihara
Published: January 2022

Objectives Detection of red cell bound immunoglobulins and/or complement by direct antiglobulin test (DAT) is a crucial serological assay in the diagnosis of autoimmune hemolytic anemia (AIHA). However, DAT may be positive in a variety of clinical conditions with or without hemolysis. We aimed at evaluating the clinical and serological correlation of positive DAT by categorizing the clinical conditions associated with positive DAT, estimating the presence of in vivo hemolysis in case of positive DAT with polyspecific and monospecific antisera and correlating the strength of positive DAT with the presence of hemolysis.

Materials and Methods The prospective observational study was performed on 200 samples that were positive for DAT with polyspecific antiglobulin reagent as the baseline investigation. These samples were further tested with anti-immunoglobulin G and anti-C3 monospecific DAT reagents to evaluate the type of protein responsible for positive DAT. The antiglobulin tests were performed by tube technique. DAT positivity was graded (1+ to 4 + ) in each patient. Autocontrol test was included. The patients with positive polyspecific DAT were categorized into different clinical conditions. The presence or absence of in vivo hemolysis was evaluated in all clinical categories and also for each grade of positivity with polyspecific and monospecific antiglobulin reagents.

Statistical Analysis Binomial logistic regression and Mann–Whitney U test were applied to between the group analyses. For categorical variables, Fisher's exact test and relative risk were used. The qualitative data were expressed in numbers and percentages.

Results The highest number of patients (75/200, 37.5%) belonged to the autoimmune diseases group. Tuberculosis and hepatitis C were the main infectious diseases associated with positive DAT. Out of 200 DAT-positive patients, 98 (49%) had in vivo hemolysis and 102 (51%) did not have hemolysis. AIHA (22) and systemic lupus erythematosus (18) were the commonest clinical conditions associated with in vivo hemolysis. All the 11 samples that showed positivity with only anti-C3 reagent did not show any hemolysis. There was statistically significant increase in the incidence of in vivo hemolysis with increasing grades of DAT positivity with all the three antihuman globulin reagents.

Conclusion There are different disease conditions which show positive DAT with or without hemolysis. So, it is important to clinically and serologically correlate positive DAT results.
On Wasserstein-1 distance in the central limit theorem for elephant random walk
Authors: Ma Xiaohui , El Machkouri Mohamed , Fan Xiequan
Published: January 2022

Recently, the elephant random walk has attracted much attention. A wide range of literature studies are available for the asymptotic behavior of the process, such as central limit theorems, functional limit theorems, and the law of the iterated logarithm. However, there is no result concerning the Wasserstein-1 distance for normal approximations. In this paper, we show that the Wasserstein-1 distance in the central limit theorem is totally different when a memory parameter p belongs to one of the three cases 0 < p < 1/2, 1/2 < p < 3/4, and p = 3/4.
On the Heisenberg algebra associated with the rational R-matrix
Authors: Butorac Marijana , Kožić Slaven
Published: January 2022

We associate a deformation of the Heisenberg algebra with the suitably normalized Yang R-matrix, and we investigate its properties. Moreover, we construct new examples of quantum vertex algebras, which possess the same representation theory as the aforementioned deformed Heisenberg algebra.
Passive near-field imaging via grating-based spectroscopy
Authors: Sakuma R. , Lin K.-T. , Kim S. , Kimura F. , Kajihara Y.
Published: January 2022

Passive scattering-type scanning near-field optical microscopy (s-SNOM) has recently been developed for studying long-wavelength infrared (LWIR) waves. It detects surface-localized waves without any external illumination or heating and enables the imaging of hot-electron energy dissipation and nanoscale Joule heating. However, the lack of a wavelength selection mechanism in the passive LWIR s-SNOM makes it difficult to perform a thorough analysis of the surface-localized waves. Here, we develop a novel passive scanning near-field optical spectroscopy with a diffraction grating. The spectroscopic optics are designed to exhibit a high signal efficiency and mechanical performance at the temperature of liquid helium (4.2 K). Using the developed passive LWIR near-field spectroscopy, the spectral information of thermally excited evanescent waves can be directly obtained without any influence from the external environment factors, including environmental heat. We have detected the thermally excited evanescent waves on a SiC/Au micropatterned sample at room temperature with a spatial resolution of 200 nm and a wavelength resolution of 500 nm at several wavelengths in the range of 14–15 µm. The obtained spectra are consistent with the electromagnetic local density of states calculated based on the fluctuation–dissipation theorem. The developed passive LWIR near-field spectroscopy enables the spectral analysis of ultrasmall surface-localized waves, making it a high-performance surface analysis tool.
Differential effects of vascular endothelial growth factor on glycocalyx of endothelial and tumor cells and potential targets for tumor metastasis
Authors: Xia Yifan , Li Yunfei , Fu Bingmei M.
Published: January 2022

On the surface of every mammalian cell, there is a matrix-like glycocalyx (GCX) consisting of proteoglycans and glycosaminoglycans (GAGs). Disruption of endothelial cell (EC) GCX by a vascular endothelial growth factor (VEGF, VEGF-A165), a tumor secretion, was found to be an early event in tumor cell (TC) metastasis across vascular barriers. However, how the TC secretion VEGF affects its own GCX is unknown. To investigate the VEGF effect on TC GCX and to elucidate the ultrastructural organization of EC and TC GCX and their alteration by VEGF, we employed super-resolution stochastic optical reconstruction microscopy to observe the spatio-chemical organizations of the heparan sulfate (HS) and hyaluronic acid (HA), two representative GAGs of GCX, on human cerebral microvascular endothelial cells (hCMEC) and malignant breast cancer cells MDA-MB-231 (MB231). We found that HS and HA have distinct organizations on hCMEC and MB231. Only HS of hCMEC is perpendicular to the cell surface, while HA of hCMEC as well as HS and HA of MB231 all lie in the same plane as the cell surface where they appear to weave into a 2D network covering the cell. We also found that VEGF significantly reduces the length and coverage of HS on hCMEC but does not change the thickness and coverage of HA on hCMEC. On the contrary, VEGF significantly enhances the coverage of HS and HA on MB231 although it does not alter the thickness. The differential effects of VEGF on the GCX of TC and that of EC may favor TC adhesion and transmigration across EC barriers for their metastasis.
Design and fabrication of a large-range graphene/hexagonal boron nitride heterostructure based pressure sensor with poly(methyl methacrylate) substrate
Authors: Zhang Guodong , Zhao Yulong , Sun Jing
Published: January 2022

Aiming at overpressure measurement, this paper presents a large-range graphene/hexagonal boron nitride (h-BN) heterostructure-based pressure sensor with a poly(methyl methacrylate) (PMMA) substrate. Graphene and h-BN are chosen as sensitive materials because they both have large Young’s modulus, high intrinsic strength, high natural frequency, and atomic thickness at the same time. These characteristics provide favorable conditions for the application of the sensor in the high pressure and high frequency dynamic environment. Moreover, the photoresist-assisted transfer technology is proposed for transferring graphene from the growth substrate to the PMMA substrate and the lift-off method with exposure and development is developed to achieve metal patterning on the PMMA substrate. The sensor characterization results suggest that the graphene and h-BN films have good transfer qualities and the heterojunction possesses excellent electrical performance. The static pressure loading experiments confirm that the sensor has a pressure range of up to 85 MPa and its piezoresistive coefficient is 0.7 GPa−1, which indicates that the designed sensor is suitable for overpressure fields. This study provides a novel method for determining overpressure and lays a foundation for the fabrication of graphene-based electronic devices with an organic substrate.
Impact of low-frequency oscillations on ion energy in a high-power magnetically shielded Hall thruster
Authors: Roberts Parker J. , Chaplin Vernon H. , Lopez Ortega Alejandro , Mikellides Ioannis G.
Published: January 2022

Plasma oscillations below 100 kHz in a high-power, magnetically shielded Hall-effect thruster are characterized experimentally. A time-resolved laser-induced fluorescence diagnostic was used to measure the evolution of the axial ion velocity distribution along the discharge channel centerline. A method was developed to correct for artificial broadening of the distribution due to finite spatial resolution, enabling accurate ion temperature measurements in the acceleration region. Time-dependent ion heating behavior is revealed, which varies with axial location. Electrostatic, collisionless particle-pushing calculations were employed to simulate the effects of a shifting acceleration front on ion motion. It is found that ions exchange energy with these oscillations, which accounts for a portion of the ion velocity fluctuations observed in the thruster plume. Phasing relationships between ion dynamics and discharge current oscillations are discussed in the context of prior Hall thruster experiments.
Modeling of shock-induced force on an isolated particle in water and air
Authors: Behrendt Jacob , Balachandar S. , Garno Joshua , McGrath Thomas P.
Published: January 2022

The prediction of force on an isolated particle, while a shock is passing over it, is an important problem in many natural and industrial applications. Although the flow monotonically changes from the pre-shock to the post-shock state, the particle's force has been observed to behave nonmonotonically with a sharp peak when the shock is located halfway across the particle. This nonmonotonic behavior is due to the unsteady nature of the compression and rarefaction waves that radiate as the shock diffracts around the particle and, therefore, cannot be predicted by a quasi-steady model. An accurate force model must account for the unsteady nature of the flow and the sharp discontinues in the flow properties across the shock. In this work, we test four different inviscid models and observe that the compressible Maxey–Riley–Gatignol (C-MRG) model is the most accurate based on comparison with results from particle-resolved inviscid simulations at two different Mach numbers for both water and air as the medium. The C-MRG model is first demonstrated to predict the force on a stationary particle accurately and then extended to capture the force on a moving particle. Numerical complexities regarding the implementation of the C-MRG model are also discussed.
Time-modulated active frequency selective surface absorber/reflector for spectrum conversion
Authors: Zhao Feng , Wang Junjie , Feng Dejun , Wu Qihua , Liu Xiaobin
Published: January 2022

Spectrum conversion involves the movement of a signal from one frequency to another, and it is well-studied in materials interacting with electromagnetic waves from microwave to optical frequencies. In this paper, a time-modulated active frequency selective surface (AFSS) absorber/reflector is proposed to manipulate the spectral distribution of the echo signal. The discrete harmonics based on the period modulation and the continuous spectrum based on the random coding modulation are analyzed in detail. In addition, a simple digital-coding control network based on field programmable gate array (FPGA) in the time-modulated AFSS absorber/reflector (TMAAR) is used to switch between absorbing and reflecting states flexibly. By coding “0” and “1” elements with the controlled sequences, the TMAAR is able to achieve the predefined modulation function for spectrum conversion. On this basis, a prototype of the designed TMAAR is manufactured. The linear frequency modulation radar echo experiments are performed to verify the required function of spectrum conversion.
Photovoltaic sensing of a memristor based in LSMO/BTO/ITO ferroionic tunnel junctions
Authors: Tenreiro Isabel , Rouco Víctor , Sánchez-Santolino Gabriel , Gallego Fernando , Leon Carlos , Rivera-Calzada Alberto , Schuller Ivan K. , Santamaria Jacobo
Published: January 2022

Memristors based on oxide tunnel junctions are promising candidates for energy efficient neuromorphic computing. However, the low power sensing of the nonvolatile resistive state is an important challenge. We report the optically induced sensing of the resistive state of a memristor based on a La0.7Sr0.3MnO3/BaTiO3/In2O3:SnO2 (90:10) heterostructure with a 3 nm thick BaTiO3 ferroelectric barrier. The nonvolatile memristive response originates from the modulation of an interfacial Schottky barrier at the La0.7Sr0.3MnO3/BaTiO3 interface, yielding robust intermediate memristive states. The Schottky barrier produces a photovoltaic response when illuminated with a 3.3 eV UV LED, which depends on the state. The open circuit voltage Voc correlates linearly with the resistance of each state, enabling active sensing of the memristive state at light power densities as low as 20 mW/cm2 and temperatures up to 100 K. This opens up avenues for the efficient and minimally invasive readout of the memory states in hybrid devices.
Understanding how minority relativistic electron populations may dominate charge state balance and radiative cooling of a post-thermal quench tokamak plasma
Authors: Garland Nathan A. , Chung Hyun-Kyung , Zammit Mark C. , McDevitt Christopher J. , Colgan James , Fontes Christopher J. , Tang Xian-Zhu
Published: January 2022

Minority relativistic electron populations can occur in a range of complex plasmas. Of specific interest is when runaway electrons form among the presence of high-atomic-number ion species in a tokamak plasma discharge. It has been recently demonstrated that ion charge state distributions and radiation losses at low bulk electron temperatures can be dominated by relativistic electrons, even though their density is orders of magnitude lower. This was attributed to the relativistic enhancement of electron impact inelastic cross sections. In this work, we provide a closer inspection of the atomic physics underpinning this effect. We also demonstrate the consequences of runaway enhanced scattering on post-disruption tokamak fusion discharges with neon and argon impurities present. Effects on charge state distributions, radiation and spectral characteristics, and reduced-order modeling considerations are discussed.
Correlation between the relative blob fraction and plasma parameters in NSTX
Authors: Zweben S. J. , Banerjee S. , Bisai N. , Diallo A. , Lampert M. , LeBlanc B. , Myra J. R. , Russell D. A.
Published: January 2022

This paper presents a simple analysis of the fraction of blobs observed in the scrape-off layer of NSTX and calculates the correlation between this blob fraction and various plasma parameters. The measurements were made using the gas puff imaging (GPI) diagnostic on a database of 103 shots from 2010 with neutral beam power PNBI = 0–6 MW. The blob fraction ranged from fb = 0.1% to 4.8%, where fb is defined as the fraction of time the GPI signal was larger than three times its average value within 0–7.5 cm outside the separatrix. The blob fraction generally decreased with increasing neutral beam injection power and was lower on average in H-mode plasmas than Ohmic and L-mode plasmas. The blob fraction had its highest correlation with the measured poloidal turbulence velocity and its radial gradient just inside the separatrix. This is in part consistent with a model in which the blob generation rate increases with the poloidal velocity shear.
Domain structures induced by tensile thermal strain in epitaxial PbTiO3 films on silicon substrates
Authors: Sato Tomoya , Kodera Masanori , Ichinose Daichi , Mimura Takanori , Shimizu Takao , Yamada Tomoaki , Funakubo Hiroshi
Published: January 2022

The fabrication of epitaxial ferroelectric materials on Si substrates is key to the design of superior ferroelectric devices for applications involving microelectromechanical systems (MEMS). The domain structures of epitaxial PbTiO3 films grown on Si substrates with an epitaxial SrTiO3 buffer layer were investigated, especially in terms of film thickness dependence. The low thermal expansion coefficient of Si was found to affect the volume fraction of (001)-oriented domains not only in relatively thick film regions but also in the thinner ones. Compared with the PbTiO3 films deposited on SrTiO3 substrates, (100)-oriented domains were observed in films as thin as 18 nm, notwithstanding the strong misfit strain induced by the substrate. Moreover, the saturated volume fraction of the (001)-oriented domain was smaller than that of PbTiO3 on SrTiO3. Thermal strain plays a critical role in determining domain structures and is, therefore, expected to govern the electric properties of films useful in MEMS devices.
Non-Newtonian and viscoplastic models of a vertically aligned thick liquid film draining due to gravity
Authors: Alahmadi Hani Nami , Naire Shailesh
Published: January 2022

We consider theoretically the two-dimensional flow in a vertically aligned thick liquid film supported at the top and bottom by wire frames. The film gradually thins as the liquid drains due to gravity. We focus on investigating the influence of non-Newtonian and viscoplastic effects, such as shear thinning and yield stress, on the draining and thinning of the liquid film, important in metallic and polymeric melt films. Lubrication theory is employed to derive coupled equations for a generalized Newtonian liquid describing the evolution of the film's thickness and the extensional flow speed. We use the non-Newtonian (power-law and Carreau) and viscoplastic (Bingham and Herschel–Bulkley) constitutive laws to describe the flow rheology. Numerical solutions combined with asymptotic solutions predict the late-time power-law thinning rate of the middle section of the film. For a Newtonian liquid, a new power law thinning rate of t−2.25 is identified. This is in comparison with a thinning rate of t−2 predicted for a thin Newtonian liquid film neglecting gravity, suggesting a weak dependence on gravity for the drainage of thicker films. For a non-Newtonian and viscoplastic liquid, varying the power law index and the yield stress influences the timescale of the thinning, but has weak dependence on the late-time thinning rate relative to the Newtonian thinning rate. The shortcomings of the power-law model are exposed when the shear rate is low and these are resolved using the Carreau model.
Mimicking gravitational lens on a thin elastic plate
Authors: Xu Shaohang , Su Guangyuan , Zhang Yunhao , Liu Yongquan
Published: January 2022

Metamaterials, together with transformation optics, have been exploited to study the effects of curved spacetime predicted by Einstein's general theory of relativity in the laboratory. However, the stringent requirements in metamaterial fabrications and the narrow operating frequency make their realistic implementations challenging. In this work, we propose and demonstrate experimentally a paradigm to mimic the gravitational lensing effect using flexural waves in an elastic plate without using metamaterials. The needed refractive index field is fulfilled just by slightly varying the local thickness of plates. The generated focusing effect has a broad band from 5 to 100 kHz and shows robustness against changes on structural shapes and thicknesses of the lens. This work provides insight to study nontrivial gravitational phenomena analogically using conventional solid structures and may suggest a possible route to regulate elastic waves arbitrarily.
Ultrafast optical control over spin and momentum in solids
Authors: Shallcross S. , Li Q. Z. , Dewhurst J. K. , Sharma S. , Elliott P.
Published: January 2022

Employing state-of-the-art first principles calculations, we show that hybrid laser pulses combining linearly and circularly polarized light allow for the excitation of free carriers of chosen spin at the arbitrary k-vector with the Brillouin zone of WSe2. The linear terahertz linear component of the pulse induces adiabatic intra-band evolution, serving to link an arbitrary point k0 to one of the high symmetry K points over a single pulse cycle. The circularly polarized component induces interband transitions at one of the two inequivalent K points that, due to the linear pulse, results at full cycle in laser excited charges at the desired k-vector k0 and not at the high symmetry K point. We, thus, theoretically predict a generalized form of the spin-valley locking in dichalcogenides, opening the way to the preparation of arbitrary momenta and spin specified excited states at ultrafast time scales.
Leakage mechanism in ion implantation isolated AlGaN/GaN heterostructures
Authors: Yu Hao , Putcha Vamsi , Peralagu Uthayasankaran , Zhao Ming , Yadav Sachin , Alian Alireza , Parvais Bertrand , Collaert Nadine
Published: January 2022

We report a comprehensive analysis of the leakage current mechanism in ion implantation isolation (I/I/I) regions of GaN high electron mobility transistors. We applied a three-step high-energy low-dose N I/I/I to AlGaN/AlN/GaN heterostructures. High-quality isolation is achieved with isolation sheet resistances Rsh in the range of 1013–1015 Ω/sq. The analysis of isolated heterostructures with varied AlGaN or AlN thicknesses indicates common electron leakage paths at the surface of GaN. The electrostatics of the leakage path is determined by an interplay between the high densities of defects created by I/I/I, the net sheet polarization charges between III-nitrides, and the AlGaN surface states. We find that the activation energy of Rsh positively correlates with the energy level of the leakage path. The energy band diagram of the isolation region is constructed by correlating the activation energies of Rsh with the heteerostructure electrostatics. Moreover, our study makes a novel method to estimate the net active defect density caused by I/I/I: net active defect densities of ∼2 × 1019 and ∼2 × 1018 cm−3 are extracted in the GaN and AlGaN layers, respectively.
Cough/X-ray/CT (CXC) website for testing COVID-19 and auto-informing results
Authors: Mahmood Ahlam Fadhil , Mahmood Saja Waleed
Published: January 2022

Despite the development of vaccines and the emergence of various treatments for COVID-19, the number of confirmed cases of the coronavirus disease (COVID-19) is increasing worldwide, and it is unlikely that the disease will ever disappear completely. Having a non-contact remote testing system can improve the workload of health-care centers and contribute to reducing the infection by recommending early self-isolation for those who suffer from a cough. In the proposed system, patients can upload an audio cough recording via mobile phones through the suggested Cough/X-ray/CT website and then receive the diagnosis within seconds on the same phone. Moreover, in the case of infection, the health center and the community are informed in addition to automatically calling the mobile phones of the injured cases. The higher proposed accuracy with deep cough training was achieved on the ResNet152v2 model after converting the cough signal into an image using the Mel-spectrogram, where the accuracy was 99.95%, the sensitivity was 100%, and the specificity was 99%.
State-resolved ultrafast charge and spin dynamics in [Co/Pd] multilayers
Authors: Le Guyader Loïc , Higley Daniel J. , Pancaldi Matteo , Liu Tianmin , Chen Zhao , Chase Tyler , Granitzka Patrick W. , Coslovich Giacomo , Lutman Alberto A. , Dakovski Georgi L. , Schlotter William F. , Shafer Padraic , Arenholz Elke , Hellwig Olav , Lalieu Mark L. M. , Koopmans Bert , Reid Alexander H. , Bonetti Stefano , Stöhr Joachim , Dürr Hermann A.
Published: January 2022

We use transient absorption spectroscopy with circularly polarized x rays to detect laser-excited hole states below the Fermi level and compare their dynamics with that of unoccupied states above the Fermi level in ferromagnetic [Co/Pd] multilayers. While below the Fermi level, an instantaneous and significantly stronger demagnetization is observed, above the Fermi level, the demagnetization is delayed by 35 ± 10 fs. This provides a direct visualization of how ultrafast demagnetization proceeds via initial spin-flip scattering of laser-excited holes to the subsequent formation of spin waves.
Perspective on thermal conductance across heterogeneously integrated interfaces for wide and ultrawide bandgap electronics
Authors: Cheng Zhe , Graham Samuel , Amano Hiroshi , Cahill David G.
Published: January 2022

Heterogeneous integration is important to create multi-functionality in future electronic devices. However, few thermal studies of the interfaces formed in these integrated devices have been reported before. Recently, integrated interfaces by surface-activated bonding were found to have high thermal boundary conductance, which provides a solution for heat dissipation of GaN and β-Ga2O3-based power electronics. Here, we review the recent progress on the interfacial thermal transport across heterogeneously integrated interfaces, including transferred van der Waals force bonded interfaces, surface-activated bonded interfaces, plasma bonded interfaces, and hydrophilic bonded interfaces. This Perspective specifically focuses on applications of thermal management strategies of electronics, especially power electronics. Finally, the challenges, such as high-throughput thermal measurements of buried interfaces, thermal property-structure relations of interfaces bonded under different conditions, theoretical understanding of interfacial thermal transport, and device demonstrations, are pointed out.
Terahertz plasma edge engineering in semiconductor membranes with a two-dimensional electron layer
Authors: Astrakhantseva A. S. , Shuvaev A. , Gusikhin P. A. , Pimenov A. , Kukushkin I. V. , Muravev V. M.
Published: January 2022

We have studied the terahertz response of a dielectric membrane with a high-mobility two-dimensional electron system (2DES) on one side. The developed device exhibits electromagnetic transparency above the plasma frequency that is found to be determined by the 2DES density and membrane thickness. Significantly, we demonstrate the opaque low-frequency region to be highly tunable. Our results can find applications in the area of active terahertz devices.