bluuebunny/crossref_metadata_2025 huggingface dataset:
Formation, distribution, and IR emission of dust in the clumpy ejecta of Type II-P core-collapse supernovae, in isotropic and anisotropic scenarios
Authors: Sarangi Arkaprabha
Published: October 2022

Large discrepancies are found between observational estimates and theoretical predictions when exploring the characteristics of dust formed in the ejecta of a core-collapse supernovae. We revisit the scenario of dust production in typical supernova ejecta in the first 3000 days after explosion, with an improved understanding of the evolving physical conditions and the distribution of the clumps. The generic, nonuniform distribution of dust within the ejecta was determined and using that, the relevant opacities and fluxes were calculated. The dependence of the emerging fluxes on the viewing angle was estimated for an anisotropic, ellipsoidal geometry of the ejecta that imitate SN 1987A. We model the He core from the center to its outer edge as 450 stratified, clumpy, annular shells, uniquely identified by their distinct velocities and characterized by their variations in abundances, densities, and gas and dust temperatures. We find that the formation of dust starts between day 450 and day 550 post-explosion, and it continues until about day 2800, although the first 1600 days are the most productive. The total dust mass evolves from ~10−5 M⊙ at day 500 to 10−3 M⊙ at day 800, finally saturating at about 0.06 M⊙. The masses of the O-rich dust (silicates, alumina) dominates the C-rich dust (amorphous carbon, silicon carbide) at all times; the formation of carbon dust is delayed beyond 2000 days post-explosion. We show that the opacities are largest between days 800 and 1600, and the characteristic spectral features of O-rich dust species are suppressed at those times. The fluxes emerging along the smallest axes of the ellipsoidal ejecta are found to be the most obscured, while a viewing angle between 16 to 21° with that axis appears to be in best agreement with the fluxes from SN 1987A at days 615 and 775.
Synthesis and properties of pyrrhotite ash based cubical α-Fe2O3 nanoparticles
Authors: Hatimi Badreddine , Mouldar Jihan , Loudiki Abdelwahed , Bensemlali Meryem , El Gaini Layla , Hajjaji Abdelowahed , El Mhammedi Moulay Abderrahim , Bakasse Mina
Published: October 2022

Pyrrhotite ash is a solid waste widely generated from the phosphate industry and has been used in this present research as a source material for α-Fe2O3 nanoparticles synthesis. The iron extraction conditions from pyrrhotite ash using hydrochloric acid were carried out under the optimized conditions. The obtained FeCl3 was deployed in the elaboration of hematite (α-Fe2O3) nanoparticles using the co-precipitation method where green tea extract was deployed as a reducer and capping agent. The prepared α-Fe2O3 nanoparticles were characterized by XRD, SEM, FTIR and BET techniques. The prepared sample consists of cubical or spherical microporous nanoparticles with sizes ranging from 56 to 116 nm and average pore size of 0.78 nm. The elaborated nanoparticles are of high purity having a crystalline size ranged from 18.33 to 24.55 nm. The optical properties were investigated using UV–visible spectroscopy, the maximum visible light absorbance was observed at 350 nm while the corresponding gap band was determined as 2.11 eV. Furthermore, the Vibrating-sample magnetometer was used to examine the magnetic properties of the nanoparticles that appropriate a ferromagnetic behaviour with high Ms, Mr, and Hc values of 14.59 emu/g and 4.72 emu/g −769.35 Oe.
Zur medizinischen Indikation bei ästhetisch-plastischen
Operationen
Authors: Allert Sixtus , Germann Günter
Published: October 2022

Der Begriff der Indikation wird in der Medizin und in der Gesundheitswirtschaft
vielfältig gebraucht. Oft in Verbindung mit
„medizinisch“ und/oder
„ärztlich“ wird zumeist der Weg zwischen Arzt und
Patient beschrieben, nach Abwägung aller vorhandenen Informationen ein
gemeinsames Behandlungsziel zu beschreiben und daraus abgeleitete
Maßnahmen zu definieren. Aus heutiger Sicht spielt allerdings noch ein
dritter Faktor eine Rolle: die Gesundheitswirtschaft, hier insbesondere in Form
der Krankenversicherungen (sowohl GKV als auch PKV), aber neuerdings auch in
Form der Finanzverwaltungen. In der Plastischen Chirurgie zeigt sich das
Dilemma, dass trotz in vielen Fällen aus ärztlicher Sicht
gesicherter Indikation weder die Kostenträger noch Finanzgerichte oder
-ämter bereit sind, der ärztlichen Einschätzung zu
folgen und die Indikationsstellung (zumeist ohne Begründung) ablehnen.
Die Arbeit bietet Hilfestellung zur Definition einer Indikation bei
ästhetisch plastischen Eingriffen.
Improving Tobacco Cessation Rates Using Inline Clinical Decision Support
Authors: Drake Lauren A. , Suresh Krithika , Chrastil Hillary , Lewis Carmen L. , Altman Richard L.
Published: October 2022

Background Tobacco use is a significant cause of morbidity and mortality in the United States. Even brief advice from a clinician can significantly influence cessation rates among tobacco users, but clinicians often miss opportunities to provide this simple intervention.

Objectives The intent of this quality improvement project was to increase tobacco cessation among tobacco users by nudging clinicians using a clinical decision support (CDS) tool.

Methods We developed a CDS tool using principles of user-centered design and the CDS Five Rights to dynamically insert actionable information about current tobacco users into the Assessment and Plan section of clinicians' notes. We conducted a retrospective analysis of patients at four primary care practices in the Denver Metro area evaluating the impact of the CDS tool on time to tobacco cessation. A multivariable Cox proportional-hazards model was used in this determination. Kaplan–Meier curves were used to estimate tobacco cessation probabilities at 90, 180, and 365 days.

Results We analyzed 5,644 patients with a median age of 45 years, most of whom lived in an urban location (99.5%) and the majority of whom were males (60%). The median follow-up time for patients was 16 months. After adjustment for age, gender, practice site, and patient location (rural, urban), the intervention group had significantly greater risk of tobacco cessation compared to those in the control group (hazard ratio: 1.22, 95% confidence interval: 1.08–1.36; p = 0.001).

Conclusion This study suggests a CDS intervention which respects the CDS Five Rights and incorporates user-centered design can affect tobacco use rates. Future work should expand the target population of this CDS tool and continue a user-centered, iterative design process.
Oblique Angled Retractor for Lumboperitoneal Shunt Implantation via Lateral Abdominal Laparotomy
Authors: Yokoya Shigeomi , Oka Hideki
Published: October 2022

Background A normal retractor often interferes with the ribs and/or thighs of the ipsilateral side when the skin and abdominal muscles are towed while performing the lumboperitoneal shunt (LPS) procedure in the lateral position. To overcome this, we developed an obtuse-angled retractor.

Methods We modified the traditional retractors into oblique-angled retractors. The blade of the new retractors was bent to 60 degrees, the entire blade was thinned, and the tip of the blade was tapered.

Results To date, we have performed approximately 30 LPS procedures in the lateral position using the new oblique-angled retractor and confirmed its usefulness.

Conclusion An oblique-angled retractor helps confirm the accurate placement of the tip of the retractor blades, even in obese patients in whom the retractor often interferes with the ribs and/or thighs.
The Comprehensive Complication Index (CCI) as a Measure of Postoperative Morbidity and Neurological Outcome after Elective Intracranial Surgery
Authors: Drexler Richard , Ricklefs Franz Lennard , Pantel Tobias Fabian , Göttsche Jennifer , Westphal Manfred , Dührsen L
Published: October 2022

Background:
The Comprehensive Complication Index (CCI) is a numerical scale based on the Clavien-Dindo classification (CDC) and both are widely used to assess outcome. However, the CCI had not been described for neurosurgical procedures.

Objective:
We aimed to investigate the value of the CCI to predict outcome in patients who underwent elective intracranial surgery.

Methods:
Prospective cohort study including patients who underwent elective intracranial surgery. Complications were graded using CDC, and the CCI was calculated daily. Neurological outcome was assessed using mRS, NANO, NIHSS, and KPS.

Results:
Of 294 patients who underwent an elective intracranial procedure, 211 (71.8%) patients underwent a craniotomy, while 28 (9.5%) patients had a burr hole procedure and 55 (18.7%) patients a transsphenoidal approach. A higher blood loss was the only significant predictor for a higher CCI (OR 1.09, 95% CI 1.00-1.12, P < 0.01). Patients with a higher CCI had a longer LOS (mean: 5.4 versus 10.9 days, P < 0.01) and ICU stay (mean: 0.8 versus 2.4 days, P < 0.01). Daily CCI revealed a risk for complications after craniotomies until postoperative day (POD) 7. In patients who underwent brain tumor surgery, the resection of meningiomas and metastasis showed a similar developmental course of CCI. A significantly higher CCI was observed in patients who had a neurological deterioration at discharge ( P < 0.01).

Conclusion:
CCI is a valid scale to measure outcome after intracranial procedures and correlates with neurological outcome. Risk for adverse events after craniotomy is at highest until postoperative day 7.
Piezoelectric Actuator-Driven Pulsed Water Jet for Neurosurgery: Laboratory Evaluation with the Swine Model and Implications of Mechanical Properties
Authors: Nakagawa Atsuhiro , Endo Toshiki , Kawaguchi Tomohiro , Yamada Masato , Sato Chiaki , Kumabe Toshihiro , Iwasaki Masaki , Niizuma Kuniyasu , Kanamori Masayuki , Nakanishi Chikashi , Yamashita Shinichi , Nakano Toru , Tominaga Teiji
Published: October 2022

Background Pulsed water jet is an emerging surgical instrumentation intended to achieve both maximal lesion resection and functional maintenance through preservation of fine vessels and minimal damage to the surrounding tissue. The piezoelectric actuator-driven pulsed water jet (ADPJ) is a new technology that can deliver a precisely controlled uniform and efficient pulsed water jet with minimum water flow. The present study evaluated the ADPJ system in preclinical animal studies in the swine brain, and investigated breaking strength, one of the parameters for mechanical properties, to elucidate the mechanism of tissue selectivity for tissue dissection by the water jet.

Methods This system consisted of a pump chamber driven by a piezoelectric actuator, a stainless steel tube, and a nozzle (internal diameter: 0.15 mm). Water was supplied at 6 ml/min. The relationship between input voltage (3–25 V at 400 Hz) and peak pressure was measured using a pressure sensor through a sensing hole. The temporal profile of dissection depth during moving application was evaluated using gelatin brain phantom and swine brain. The dissected specimens were evaluated histologically. The mechanical property (breaking strength) of the swine brain was measured by a compact table-top universal tester.

Results Peak pressure increased linearly with increase in input voltage, which reflected the dissection depth in both the gelatin brain phantom and swine brain. Small arteries were preserved, and minimum damage to surrounding tissues occurred. The breaking strength of the arachnoid membrane (0.12 ± 0.014 MPa) was significantly higher compared with the gray matter (0.030 ± 0.010 MPa) and white matter (0.056 ± 0.009 MPa; p < 0.05). The breaking strength of the gray matter corresponded to that of 3 wt% gelatin, and that of white matter corresponded to a value between 3.5 and 4 wt% gelatin, and the dissection depth seemed to be estimated at 3 to 4 wt% gelatin.

Conclusion The present study suggests that the ADPJ system has the potential to achieve accurate tissue dissection with preservation of blood vessels in neurosurgery. The difference in breaking strength may explain the tissue selectivity between the brain parenchyma and tissue protected by the arachnoid membrane.
Impaired Platelet Function and Thrombus Formation in PDE5A-Deficient Mice
Authors: Gui Xiang , Chu Xiang , Du Yuwei , Wang Yuhan , Zhang Sixuan , Ding Yangyang , Tong Huan , Xu Mengdi , Li Yue , Ju Wen , Sun Zengtian , Li Zhenyu , Zeng Lingyu , Xu Kailin , Qiao Jianlin
Published: October 2022

Intracellular cyclic GMP (cGMP) inhibits platelet function. Platelet cGMP levels are controlled by phosphodiesterase 5A (PDE5A)-mediated degradation. However, the exact role of PDE5A in platelet function and thrombus formation remains poorly understood. In this study, we characterized the role of PDE5A in platelet activation and function. Platelets were isolated from wild type or PDE5A−/− mice to measure platelet aggregation, activation, phosphatidylserine exposure (annexin-V binding), reactive oxygen species (ROS) generation, platelet spreading as well as clot retraction. Cytosolic calcium mobilization was measured using Fluo-4 AM by a microplate reader. Western blot was used to measure the phosphorylation of VASP, ERK1/2, p38, JNK, and AKT. FeCl3-induced arterial thrombosis and venous thrombosis were assessed to evaluate the in vivo hemostatic function and thrombus formation. Additionally, in vitro thrombus formation was assessed in a microfluidic whole-blood perfusion assay. PDE5A-deficient mice presented significantly prolonged tail bleeding time and delayed arterial and venous thrombus formation. PDE5A deficiency significantly inhibited platelet aggregation, ATP release, P-selectin expression, and integrin aIIbb3 activation. In addition, an impaired spreading on collagen or fibrinogen and clot retraction was observed in PDE5A-deficient platelets. Moreover, PDE5A deficiency reduced phosphatidylserine exposure, calcium mobilization, ROS production, and increased intracellular cGMP level along with elevated VASP phosphorylation and reduced phosphorylation of ERK1/2, p38, JNK, and AKT. In conclusion, PDE5A modulates platelet activation and function and thrombus formation, indicating that therapeutically targeting it might be beneficial for the treatment of thrombotic diseases.
Hidden policy conflicts? Administrative strategies to manage depoliticisation
Authors: Skoog Louise , Svensson Petra
Published: October 2022

As a way to manage political disagreements over public policies, political representatives might be tempted to avoid open discussions by depoliticising political issues—hoping that the conflict may eventually disappear. When decision-makers employ such strategies, it is up to the administration to make political priorities and manage unresolved policy conflicts. Earlier studies indicate that there are at least two strategies that administrators can employ to manage such ambiguities: (re)framing and technical depoliticisation. This article reveals that public administrators also employ a third framing strategy: repoliticisation, where administrators seek to endow their policy areas with political power by connecting politicians to the work and implementation of policies. The study is based on 38 interviews from 11 municipalities in Sweden.
Simulating polymer crystallization inside nanodroplets
Authors: Piccone Ashley
Published: October 2022

Crystallization begins near the droplet surface, and nucleation rate per unit volume increases with decreasing droplet size.
Improving urban growth models with fractional calculus
Authors: Piccone Ashley
Published: October 2022

The mathematical tool accounts for complex systems where changes do not occur instantaneously, making it more suitable for studying cities.
Don’t sweat it: laser-induced graphene monitors analytes in sweat
Authors: Piccone Ashley
Published: October 2022

Easy and low-cost fabrication technique via laser-induced pyrolysis improves wearable sensing solutions.
Optimizing vaccination strategies for disease outbreaks
Authors: Thompson Avery
Published: October 2022

When vaccine supply is limited, who should be inoculated first? The answer depends on demographics, rates of contagion, and lethality.
Uniform attractors for nonautonomous 2D MHD equations with partial dissipation
Authors: He Jinfang , Ma Shan , Sun Chunyou , Yang Lu
Published: October 2022

In this article, we study the long-time behavior of solutions of nonautonomous 2D magnetohydrodynamics equations with partial dissipation and time-dependent external forcing, which is weakly normal. We prove that the system possesses strong uniform attractors. Furthermore, the structure of the uniform attractors is obtained, and the fractal dimension is estimated for the kernel sections of the uniform attractors.
Evolution systems and continuity equations for white noise functionals
Authors: Ji Un Cig
Published: October 2022

In this paper, by applying the quantum decomposition of white noise functionals, the continuity equations for white noise functionals are reformulated as time inhomogeneous white noise differential equations. We establish a systematic study of the evolution systems whose infinitesimal generators are quadratic quantum white noises and then, as an application, we study the continuity equations for white noise functionals of which the coefficient has up to the first chaos (Gaussian process). The restriction for the coefficient is comparable (not necessarily equivalent) to the integrability condition of the exponential of the coefficient by Ambrosio and Figalli [J. Funct. Anal. 256, 179–214 (2009)] for the well-posedness of the continuity equation in the abstract Wiener space setting.
Comparison of Langmuir probe and optical emission spectroscopy on a volume-cusp filament ion source using helium
Authors: Savard N. , Fubiani G. , Dehnel M.
Published: October 2022

D-Pace has a Penning ion source that runs with helium for studies of α-particle production. We want to study its plasma properties as a function of varying operational parameters, which results in varied output ion beam characteristics. In order to diagnose the ion source plasma, a collisional-radiative code for helium to be used with optical emission spectroscopy measurements is developed. This has the advantage of being non-invasive, which allows for measurements using the emitted light from the plasma. This collisional-radiative code is shown to compare well with the Yacora on the Web model developed at IPP-Garching, and improves upon it with the addition of radiation trapping. Furthermore, the sensitivity of this model to the inclusion of additional excited state populations and non-Maxwellian electron energy distribution functions is investigated. It is shown that non-Maxwellian distributions can significantly affect spectroscopy measurements. This diagnostic is benchmarked to Langmuir probe measurements on the TRIUMF-licensed volume-cusp ion source to determine whether it can replicate the measured electron density and electron temperature as a function of varied operational parameters. The operational parameters are helium gas flow (10–40 SCCM), arc voltage (100–200 V), and arc current (1–5 A). The measured plasma properties, while different in absolute value, have similar trends for each operational parameter except when varying arc voltage. It is shown that this mismatch as a function of arc voltage is likely due to high energy non-Maxwellian electrons from the cathode sheath, which are not included within the collisional-radiative model.
Measurement of re-entry plasma density using microwave reflectometer in laboratory
Authors: Shin Gi Won , Kim Jae Hyeon , Lee Sun Hee , Bang In Young , Kim Ji Hwan , Park Yeon Soo , Kwon Hee Tae , Kim Woo Jae , Kwon Gi-Chung
Published: October 2022

A laboratory-scale experiment was conducted to reproduce plasma with properties similar to re-entry plasma and measure the plasma density using a microwave reflectometer system. To reproduce a similar re-entry plasma, a high-temperature refractory anode vacuum arc plasma method was used among arc plasma discharge methods, and arc plasma having high temperature, high speed, and high-density plasma characteristics was discharged inside a vacuum chamber. A hot refractory anode made of tungsten was used to show high-temperature plasma characteristics, and high-density plasma characteristics were demonstrated using re-evaporation around the anode. In addition, high-speed plasma characteristics were exhibited using a brass cathode. This kind of arc plasma discharge has a high temperature and is characterized by high fluctuation. It was determined that a microwave reflectometer system with good spatial resolution and non-invasiveness would be suitable to measure plasma with these characteristics. The reflection coefficient was measured using a reflector system by comparing the voltage between the traveling wave applied to the plasma and the reflected wave reflected by the plasma, and the technique of analyzing the plasma density using the difference between these reflection coefficients was used. In this study, the plasma density according to the pressure change was typically measured as 1012–1013 cm−3, which showed a similar tendency to the result of measuring the actual re-entry plasma density.
A low phase and amplitude noise microwave source for vapor cell atomic clocks
Authors: Ju Bowen , Yun Peter , Hao Qiang , Nie Shuai , Liu Guobin
Published: October 2022

A low-noise microwave source plays a key role in high-performance passive atomic clocks. Here, we propose and implement a microwave frequency synthesizer featuring a low phase and amplitude noise. With the help of a high-Q factor surface acoustic wave band-pass filter, we generate a microwave with targeted frequency by frequency multiplication of a low noise local oscillator at a radio frequency with the closest integer. At the frequency offset of 1 Hz, 10 Hz, 100 Hz, 1 kHz, and 10 kHz, the absolute phase noise of the output 3.417 GHz signal is −53.0, −83.3, −107.7, −119.2, and −124.0 dBc/Hz, respectively. After the microwave-to-optical conversion, the expected intermodulation effect contribution to the frequency stability of the coherent population trapping (CPT) atomic clock is 5.95 × 10−14 at an averaging time of 1 s. Meanwhile, with a feature of low fluctuation of this chain’s output microwave power at the level of 1.19 × 10−5 W at 1 s, its contribution to the frequency stability of the CPT atomic clock is 7.85 × 10−14 at the 1 s integration time. Our simple and low noise microwave chain is an ideal microwave source for high-performance, compact CPT clocks and could also be applied to cold atom or ion based microwave clocks.
Fiber Bragg grating sensor array for detecting heat flux in vacuum
Authors: Titus J. B. , Griswold M. E. , Granstedt E. M. , Magee R. M. , Charkhesht N. , Schroeder J. H. , Meekins M. , Allfrey I. ,   TAE Team
Published: October 2022

In TAE Technologies’ current experimental device, C-2W (also called “Norman”), record-breaking, advanced beam-driven field-reversed configuration plasmas are produced and sustained in steady state utilizing variable energy neutral beams, advanced divertors, edge-biasing electrodes, and an active plasma control system [Gota et al., Nucl. Fusion 61, 106039 (2021)]. A novel diagnostic has been developed by TAE Technologies to leverage an industrial fiber Bragg grating (FBG) sensor array to detect heat flux along the wall of the vacuum vessel from a plasma discharge. The system consists of an optical fiber with FBG sensors distributed along its length, housed in a pressurized steel sheath. Each FBG sensor is constructed to reflect a different wavelength, the exact value of which is sensitive to the strain and temperature at the location of the grating in the fiber. The fiber is illuminated with broadband light, and the data acquisition system analyzes the spectrum of reflected light to determine the temperature at the location of each FBG. We have installed four of these vacuum-rated FBG sensor arrays on the C-2W experiment, each with 30 individual FBG sensors spaced at 0.15 m intervals along the 5 m fiber, with a 100 Hz acquisition rate. The measurement of temperature change due to a plasma discharge provides a single data point at each sensor location, creating a 120-point heat map of the vacuum vessel.
Design of a new charge exchange recombination spectroscopy diagnostic for impurity transport experiments at Wendelstein 7-X
Authors: Swee Colin , Geiger Benedikt , Albosta Ryan , Ford Oliver , Loch Stuart , Nornberg M. D. , Schellpheffer Jacob , Wegner Thomas ,   W7-X Team
Published: October 2022

In this study, we present the design of a new charge exchange recombination spectroscopy (CXRS) system for Wendelstein 7-X (W7-X), which aims at measuring line radiation from highly ionized iron impurities after laser blow off injections over transport timescales. New fiber bundles with a core diameter of 600 µm have been added to one of the existing optical systems at W7-X used for CXRS. The fibers direct collected light to five newly developed single channel high frame rate F/2.8 spectrometers. The new custom-made spectrometers are built using entirely off-the-shelf and 3D printed components, and employ a round-to-linear fiber bundle, instead of an entrance slit, to maximize light throughput. The detector is an ultra-low readout noise EM-CCD camera capable of frame rates of up to 10 000 fps for about 500 consecutive frames when operated using a single readout channel. Such high frame rates will enable the study of inward convection of injected impurities. An initial sensitivity study is performed using a newly developed Markov chain Monte Carlo approach based on the pySTRAHL impurity transport code. This study indicates that, with the addition of the new CX diagnostic, impurity convection velocities can be inferred.
Remote surface optical phonon scattering in ferroelectric Ba0.6Sr0.4TiO3 gated graphene
Authors: Chen Hanying , Li Tianlin , Hao Yifei , Rajapitamahuni Anil , Xiao Zhiyong , Schoeche Stefan , Schubert Mathias , Hong Xia
Published: October 2022

We report the effect of remote surface optical (RSO) phonon scattering on carrier mobility in monolayer graphene gated by ferroelectric oxide. We fabricate monolayer graphene transistors back-gated by epitaxial (001) Ba0.6Sr0.4TiO3 films, with field effect mobility up to 23 000 cm2 V−1 s−1 achieved. Switching ferroelectric polarization induces nonvolatile modulation of resistance and quantum Hall effect in graphene at low temperatures. Ellipsometry spectroscopy studies reveal four pairs of optical phonon modes in Ba0.6Sr0.4TiO3, from which we extract RSO phonon frequencies. The temperature dependence of resistivity in graphene can be well accounted for by considering the scattering from the intrinsic longitudinal acoustic phonon and the RSO phonon, with the latter dominated by the mode at 35.8 meV. Our study reveals the room temperature mobility limit of ferroelectric-gated graphene transistors imposed by RSO phonon scattering.
Nonlinear dielectric properties of polyimide in high AC electric field
Authors: Diaham Sombel , Lambkin Paul , Chen Baoxing
Published: October 2022

The nonlinear dielectric properties of polyimide (PI) films, excited by high-intensity, AC electric fields, have been measured. This work highlights that nonlinear DC conduction is a component of the AC conductivity and dielectric loss response when surpassing a certain threshold field strength. An additional Poole–Frenkel polarization, induced by high-intensity, high-frequency fields, also contributes to the nonlinearity. This increases the dielectric losses through a charge de-trapping process, the so-called “jacking-up” effect. A novel expression that captures the large signal behavior of the complex permittivity is introduced using the Cole–Cole format. Finally, it is shown that the dielectric properties and power dissipation density in PI films remain fully linear and frequency-independent up to an AC electric field of EPF ∼100 Vrms/μm and more conservatively below a threshold field of EX ∼ 45 V/μm (i.e., end of the ohmic region). Consequently, polyimide-based insulated electronic devices that are designed to continuously operate below this threshold field (including both uniform and fringe fields) will remain immune to a frequency-dependent electrical aging. Their lifetime should not be affected in any way.
Dual exponential coupled cluster theory: Unitary adaptation, implementation in the variational quantum eigensolver framework and pilot applications
Authors: Halder Dipanjali , Prasannaa V. S. , Maitra Rahul
Published: October 2022

In this paper, we have developed a unitary variant of a double exponential coupled cluster theory, which is capable of handling molecular strong correlation with arbitrary electronic complexity. With the Hartree–Fock determinant taken as the reference, we introduce a sequential product of parameterized unitary Ansätze. While the first unitary, containing the excitation operators, acts directly on the reference determinant, the second unitary, containing a set of rank-two, vacuum-annihilating scattering operators, has nontrivial action only on certain entangled states. We demonstrate the theoretical bottleneck of such an implementation in a classical computer, whereas the same is implemented in the hybrid quantum–classical variational quantum eigensolver framework with a reasonably shallow quantum circuit without any additional approximation. We have further introduced a number of variants of the proposed Ansatz with different degrees of sophistication by judiciously approximating the scattering operators. With a number of applications on strongly correlated molecules, we have shown that all our schemes can perform uniformly well throughout the molecular potential energy surface without significant additional implementation cost over the conventional unitary coupled cluster approach with single and double excitations.
Mean flow data assimilation based on physics-informed neural networks
Authors: von Saldern Jakob G. R. , Reumschüssel Johann Moritz , Kaiser Thomas L. , Sieber Moritz , Oberleithner Kilian
Published: October 2022

Physics-informed neural networks (PINNs) can be used to solve partial differential equations (PDEs) and identify hidden variables by incorporating the governing equations into neural network training. In this study, we apply PINNs to the assimilation of turbulent mean flow data and investigate the method's ability to identify inaccessible variables and closure terms from sparse data. Using high-fidelity large-eddy simulation data and particle image velocimetry measured mean fields, we show that PINNs are suitable for simultaneously identifying multiple missing quantities in turbulent flows and providing continuous and differentiable mean fields consistent with the provided PDEs. In this way, consistent and complete mean states can be provided, which are essential for linearized mean field methods. The presented method does not require a grid or discretization scheme, is easy to implement, and can be used for a wide range of applications, making it a very promising tool for mean field-based methods in fluid mechanics.
Large- and small-scale characteristics in a temporally developing shearless turbulent mixing layer
Authors: Nakamura K. , Matsushima T. , Zheng Y. , Nagata K. , Watanabe T.
Published: October 2022

Direct numerical simulation of a temporally developing shearless turbulent mixing layer is performed. Two quasi-homogeneous isotropic turbulent (HIT) regions with different turbulent kinetic energies (TKEs) and a mixing-layer region temporally develop. The small-scale properties are analyzed with the velocity gradient tensor. The statistics on the velocity variances show that the development of the mixing layer is divided into two stages. In the first stage, grid turbulence in the large-TKE region has not fully developed, and the center of the mixing layer hardly moves. Large-scale intermittency grows in the mixing-layer region at this stage. In the second stage, grid turbulence in the large-TKE region has fully developed, and the center of the mixing layer moves toward the small-TKE region. The small-scale intermittency is most significant in the mixing-layer region in both stages. The statistics on the velocity gradient tensor show that stronger vortex compression occurs more frequently in the mixing-layer region than in the quasi-HIT regions at late times. In addition, the extensive and compressive eigenvalues of the rate-of-strain tensor exhibit the strongest intermittency in the mixing-layer region at late times.
Local order parameter that distinguishes crystalline and amorphous portions in polymer crystal lamellae
Authors: Takano F. , Hiratsuka M. , Aoyagi T. , Takahashi K. Z.
Published: October 2022

The degradation of microplastics in relation to marine pollution has been receiving increasing attention. Because the spherulites that comprise microplastics have a highly ordered lamellar structure, their decomposition is thought to involve a lamellar structure collapse process. However, even in the simplest case of an order–disorder transition between lamellae and melt upon heating, the microscopic details of the transition have yet to be elucidated. In particular, it is unclear whether nucleation occurs at defects in the crystalline portion or at the interface between the crystalline and amorphous portions. To observe the transition in molecular simulations, an approach that distinguishes between the crystalline and amorphous structures that make up the lamella is needed. Local order parameters (LOPs) are an attempt to define the degree of order on a particle-by-particle basis and have demonstrated the ability to precisely render complex order structure transitions during phase transitions. In this study, 274 LOPs were considered to classify the crystalline and amorphous structures of polymers. Supervised machine learning was used to automatically and systematically search for the parameters. The identified optimal LOP does not require macroscopic information such as the overall orientation direction of the lamella layers but can precisely distinguish the crystalline and amorphous portions of the lamella layers using only a small amount of neighboring particle information.
The local energy flux surrogate in turbulent open-channel flows
Authors: Servidio S. , Coscarella F. , Penna N. , Gaudio R.
Published: October 2022

We present a local analysis of turbulence in open-channel flows, using time-series velocity measurements. The method is based on a local form of the Kolmogorov “4/3-law” of homogeneous turbulence for the third-order moment of velocity increments. Following the Duchon and Robert [“Inertial energy dissipation for weak solutions of incompressible Euler and Navier–Stokes equations,” Nonlinearity 13, 249 (2000)] idea, which envisions turbulence dissipation as a lack of smoothness of the Navier–Stokes solutions, we estimate the local energy flux in a laboratory experiment with natural bed flows. Taking advantage of one-dimensional filtering techniques, under reasonable hypothesis, simple expressions of a surrogate of the energy flux are provided. The local energy flux surrogate reveals that, independently of the geometry, turbulence dissipation is highly intermittent. Among a variety of eddies that populate turbulence, dissipative singularities appear in sheet-like, tube, and filament structures, with large amplitude variations and rotations. This simplified technique can be applied to any measurement of hydrodynamic turbulence.
Relational diversity in social portfolios predicts well-being
Authors: Collins Hanne K. , Hagerty Serena F. , Quoidbach Jordi , Norton Michael I. , Brooks Alison Wood
Published: October 2022

We document a link between the relational diversity of one’s social portfolio—the richness and evenness of relationship types across one’s social interactions—and well-being. Across four distinct samples, respondents from the United States who completed a preregistered survey (
n
= 578), respondents to the American Time Use Survey (
n
= 19,197), respondents to the World Health Organization’s Study on Global Aging and Adult Health (
n
= 10,447), and users of a French mobile application (
n
= 21,644), specification curve analyses show that the positive relationship between social portfolio diversity and well-being is robust across different metrics of well-being, different categorizations of relationship types, and the inclusion of a wide range of covariates. Over and above people’s total amount of social interaction and the diversity of activities they engage in, the relational diversity of their social portfolio is a unique predictor of well-being, both between individuals and within individuals over time.
Deterministic programming of human pluripotent stem cells into microglia facilitates studying their role in health and disease
Authors: Speicher Anna M. , Korn Lisanne , Csatári Júlia , Gonzalez-Cano Laura , Heming Michael , Thomas Christian , Schroeter Christina B. , Schafflick David , Li Xiaolin , Gola Lukas , Engler Alexander , Kaehne Thilo , Vallier Ludovic , Meuth Sven G. , Meyer zu Hörste Gerd , Kovac Stjepana , Wiendl Heinz , Schöler Hans R. , Pawlowski Matthias
Published: October 2022

Microglia, the resident immune cells of the central nervous system (CNS), are derived from yolk-sac macrophages that populate the developing CNS during early embryonic development. Once established, the microglia population is self-maintained throughout life by local proliferation. As a scalable source of microglia-like cells (MGLs), we here present a forward programming protocol for their generation from human pluripotent stem cells (hPSCs). The transient overexpression of PU.1 and C/EBPβ in hPSCs led to a homogenous population of mature microglia within 16 d. MGLs met microglia characteristics on a morphological, transcriptional, and functional level. MGLs facilitated the investigation of a human tauopathy model in cortical neuron–microglia cocultures, revealing a secondary dystrophic microglia phenotype. Single-cell RNA sequencing of microglia integrated into hPSC-derived cortical brain organoids demonstrated a shift of microglia signatures toward a more-developmental in vivo–like phenotype, inducing intercellular interactions promoting neurogenesis and arborization. Taken together, our microglia forward programming platform represents a tool for both reductionist studies in monocultures and complex coculture systems, including 3D brain organoids for the study of cellular interactions in healthy or diseased environments.
Paradoxical self-sustained dynamics emerge from orchestrated excitatory and inhibitory homeostatic plasticity rules
Authors: Soldado-Magraner Saray , Seay Michael J. , Laje Rodrigo , Buonomano Dean V.
Published: October 2022

Self-sustained neural activity maintained through local recurrent connections is of fundamental importance to cortical function. Converging theoretical and experimental evidence indicates that cortical circuits generating self-sustained dynamics operate in an inhibition-stabilized regime. Theoretical work has established that four sets of weights (

W
E←E

,

W
E←I

,

W
I←E

, and

W
I←I

) must obey specific relationships to produce inhibition-stabilized dynamics, but it is not known how the brain can appropriately set the values of all four weight classes in an unsupervised manner to be in the inhibition-stabilized regime. We prove that standard homeostatic plasticity rules are generally unable to generate inhibition-stabilized dynamics and that their instability is caused by a signature property of inhibition-stabilized networks: the paradoxical effect. In contrast, we show that a family of “cross-homeostatic” rules overcome the paradoxical effect and robustly lead to the emergence of stable dynamics. This work provides a model of how—beginning from a silent network—self-sustained inhibition-stabilized dynamics can emerge from learning rules governing all four synaptic weight classes in an orchestrated manner.
Aesthetic experience enhances first-person spatial representation
Authors: Babo-Rebelo Mariana , Chatel Marie , Tabacchi Serena , Namiq Allen , Travers Eoin , James Kadine , Haggard Patrick
Published: October 2022

Episodic autobiographical memories are characterized by a spatial context and an affective component. But how do affective and spatial aspects interact? Does affect modulate the way we encode the spatial context of events? We investigated how one element of affect, namely aesthetic liking, modulates memory for location, in three online experiments (
n
= 124, 79, and 80). Participants visited a professionally curated virtual art exhibition. They then relocated previously viewed artworks on the museum map and reported how much they liked them. Across all experiments, liking an artwork was associated with increased ability to recall the wall on which it was hung. The effect was not explained by viewing time and appeared to modulate recognition speed. The liking-wall memory effect remained when participants attended to abstractness, rather than liking, and when testing occurred 24 h after the museum visit. Liking also modulated memory for the room where a work of art was hung, but this effect primarily involved reduced room memory for disliked artworks. Further, the liking-wall memory effect remained after controlling for effects of room memory. Recalling the wall requires recalling one’s facing direction, so our findings suggest that positive aesthetic experiences enhance first-person spatial representations. More generally, a first-person component of positive affect transfers to wider spatial representation and facilitates the encoding of locations in a subject-centered reference frame. Affect and spatial representations are therefore important, and linked, elements of sentience and subjectivity. Memories of aesthetic experiences are also spatial memories of how we encountered a work of art. This linkage may have implications for museum design.
Oxidation state-specific fluorescent copper sensors reveal oncogene-driven redox changes that regulate labile copper(II) pools
Authors: Pezacki Aidan T. , Matier Carson D. , Gu Xingxing , Kummelstedt Eric , Bond Sarah E. , Torrente Laura , Jordan-Sciutto Kelly L. , DeNicola Gina M. , Su Timothy A. , Brady Donita C. , Chang Christopher J.
Published: October 2022

Copper is an essential metal nutrient for life that often relies on redox cycling between Cu(I) and Cu(II) oxidation states to fulfill its physiological roles, but alterations in cellular redox status can lead to imbalances in copper homeostasis that contribute to cancer and other metalloplasias with metal-dependent disease vulnerabilities. Copper-responsive fluorescent probes offer powerful tools to study labile copper pools, but most of these reagents target Cu(I), with limited methods for monitoring Cu(II) owing to its potent fluorescence quenching properties. Here, we report an activity-based sensing strategy for turn-on, oxidation state-specific detection of Cu(II) through metal-directed acyl imidazole chemistry. Cu(II) binding to a metal and oxidation state-specific receptor that accommodates the harder Lewis acidity of Cu(II) relative to Cu(I) activates the pendant dye for reaction with proximal biological nucleophiles and concomitant metal ion release, thus avoiding fluorescence quenching. Copper-directed acyl imidazole 649 for Cu(II) (CD649.2) provides foundational information on the existence and regulation of labile Cu(II) pools, including identifying divalent metal transporter 1 (DMT1) as a Cu(II) importer, labile Cu(II) increases in response to oxidative stress induced by depleting total glutathione levels, and reciprocal increases in labile Cu(II) accompanied by decreases in labile Cu(I) induced by oncogenic mutations that promote oxidative stress.
Site-to-site cross-talk in OST-B glycosylation of hCEACAM1-IgV
Authors: Williams Robert V. , Huang Chin , McDermott Connor , Ahmed Tanvir , Columbus Linda , Moremen Kelley W. , Prestegard James H. , Amster I. Jonathan
Published: October 2022

N
-glycosylation is a common posttranslational modification of secreted proteins in eukaryotes. This modification targets asparagine residues within the consensus sequence, N–X–S/T. While this sequence is required for glycosylation, the initial transfer of a high-mannose glycan by oligosaccharyl transferases A or B (OST-A or OST-B) can lead to incomplete occupancy at a given site. Factors that determine the extent of transfer are not well understood, and understanding them may provide insight into the function of these important enzymes. Here, we use mass spectrometry (MS) to simultaneously measure relative occupancies for three
N
-glycosylation sites on the N-terminal IgV domain of the recombinant glycoprotein, hCEACAM1. We demonstrate that addition is primarily by the OST-B enzyme and propose a kinetic model of OST-B
N
-glycosylation. Fitting the kinetic model to the MS data yields distinct rates for glycan addition at most sites and suggests a largely stochastic initial order of glycan addition. The model also suggests that glycosylation at one site influences the efficiency of subsequent modifications at the other sites, and glycosylation at the central or N-terminal site leads to dead-end products that seldom lead to full glycosylation of all three sites. Only one path of progressive glycosylation, one initiated by glycosylation at the C-terminal site, can efficiently lead to full occupancy for all three sites. Thus, the hCEACAM1 domain provides an effective model system to study site-specific recognition of glycosylation sequons by OST-B and suggests that the order and efficiency of posttranslational glycosylation is influenced by steric cross-talk between adjoining acceptor sites.
Inhibition of RAS-driven signaling and tumorigenesis with a pan-RAS monobody targeting the Switch I/II pocket
Authors: Wallon Lauren , Khan Imran , Teng Kai Wen , Koide Akiko , Zuberi Mariyam , Li Jianping , Ketavarapu Gayatri , Traaseth Nathaniel J. , O’Bryan John P. , Koide Shohei
Published: October 2022

RAS mutants are major therapeutic targets in oncology with few efficacious direct inhibitors available. The identification of a shallow pocket near the Switch II region on RAS has led to the development of small-molecule drugs that target this site and inhibit KRAS(G12C) and KRAS(G12D). To discover other regions on RAS that may be targeted for inhibition, we have employed small synthetic binding proteins termed monobodies that have a strong propensity to bind to functional sites on a target protein. Here, we report a pan-RAS monobody, termed JAM20, that bound to all RAS isoforms with nanomolar affinity and demonstrated limited nucleotide-state specificity. Upon intracellular expression, JAM20 potently inhibited signaling mediated by all RAS isoforms and reduced oncogenic RAS-mediated tumorigenesis in vivo. NMR and mutation analysis determined that JAM20 bound to a pocket between Switch I and II, which is similarly targeted by low-affinity, small-molecule inhibitors, such as BI-2852, whose in vivo efficacy has not been demonstrated. Furthermore, JAM20 directly competed with both the RAF(RBD) and BI-2852. These results provide direct validation of targeting the Switch I/II pocket for inhibiting RAS-driven tumorigenesis. More generally, these results demonstrate the utility of tool biologics as probes for discovering and validating druggable sites on challenging targets.