bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toward a flow-dependent phase-stability criterion: Osmotic pressure in sticky flowing suspensions
Authors: Huang Derek E. , Zia Roseanna N. 
Published: October 2021

Equilibrium phase instability of colloids is robustly predicted by the Vliegenthart–Lekkerkerker (VL) critical value of the second virial efficient, but no such general criterion has been established for suspensions undergoing flow. A transition from positive to negative osmotic pressure is one mechanical hallmark of a change in phase stability in suspensions and provides a natural extension of the equilibrium osmotic pressure encoded in the second virial coefficient. Here, we propose to study the non-Newtonian rheology of an attractive colloidal suspension using the active microrheology framework as a model for focusing on the pair trajectories that underlie flow stability. We formulate and solve a Smoluchowski relation to understand the interplay between attractions, hydrodynamics, Brownian motion, and flow on particle microstructure in a semi-dilute suspension and utilize the results to study the viscosity and particle-phase osmotic pressure. We find that an interplay between attractions and hydrodynamics leads to dramatic changes in the nonequilibrium microstructure, which produces a two-stage flow-thinning of viscosity and leads to pronounced flow-induced negative osmotic pressure. We summarize these findings with an osmotic pressure heat map that predicts where hydrodynamic enhancement of attractive bonds encourages flow-induced aggregation or phase separation. We identify a critical isobar—a flow-induced critical pressure consistent with phase instability and a nonequilibrium extension of the VL criterion.
Design and implementation of DC-to-DC converter topology for current regulated lightning generator
Authors: Andraud V. , Sousa Martins R. , Zaepffel C. , Landfried R. , Testé P. 
Published: October 2021

When aircraft are impacted by lightning strikes, structural fuselage and components are stressed by electric and thermo-mechanical constraints which impose a need for reliable experimental test benches to design accurate and enhanced lightning protections. The aim of this work is to investigate, design, and compare different topologies of DC high-current generators in order to experimentally reproduce the continuous lightning current waveform component applied to produce an electric arc up to 1 m long. An electrical model of a standard lightning C*-waveform for a 1 m long arc is set, leading to an equivalent resistor varying from 4 to 8 Ω. This model enables a theoretical comparison between the DC/DC converters’ Buck and Buck-boost topologies to generate such a current-regulated waveform through a load using a capacitor bank and applying a minimum initial stored energy criterion. The experimental implementations of Buck and Buck-boost configurations are designed and tested. Optimizations about the accuracy of the current regulation through the feedback loop and the respect of components’ operating electrical and power parameters are presented. In particular, the implementation of a snubber filter and a frequency control of the switching operations, which are mandatory elements in the operation of DC converters, are described to prevent the circuit from damaging initiated by transient overvoltage peaks. Both Buck and Buck-boost configurations are experimentally implemented to generate a standard C* waveform through a 4 Ω resistor and the Buck configuration proves the ability to generate electric arcs up to 1.5 m respecting the standard aeronautic waveform of lightning.
A 4He vector zero-field optically pumped magnetometer operated in the Earth-field
Authors: Bertrand F. , Jager T. , Boness A. , Fourcault W. , Le Gal G. , Palacios-Laloy A. , Paulet J. , Léger J. M. 
Published: October 2021

Low intrinsic noise, high bandwidth, and high accuracy vector magnetometers are key components for many ground or space geophysical applications. Here, we report the design and the test of a 4He vector optically pumped magnetometer specifically dedicated to these needs. It is based on a parametric resonance magnetometer architecture operated in the Earth magnetic field with closed-loop compensation of the three components of the magnetic field. It provides offset-free vector measurements in a ±70 μT range with a DC to 1 kHz bandwidth. We demonstrate a vector sensitivity up to 130 fT/√Hz, which is about ten times better than the best available fluxgate magnetometers currently available for the same targeted applications.
Capacity of soil bacteria to reach the phyllosphere and convergence of floral communities despite soil microbiota variation
Authors: Massoni Julien , Bortfeld-Miller Miriam , Widmer Alex , Vorholt Julia A. 
Published: October 2021

Significance
The role of flowers as environmental filters for bacterial communities and the provenance of bacteria in the phyllosphere are currently poorly understood. We experimentally tested the effect of induced variation in soil communities on the microbiota of plant organs. We identified soil-derived bacteria in the phyllosphere and show a strong convergence of floral communities with an enrichment of members of the Burkholderiaceae family. This finding highlights a potential role of the flower in shaping the interaction between plants and a bacterial family known to harbor both plant pathogens and growth-promoting strains. Because the flower involves host–symbiont feedback, the selection of specific bacteria by the reproductive organs of angiosperms could be relevant for the modulation of fruit and seed production.
Phytoplankton exudates and lysates support distinct microbial consortia with specialized metabolic and ecophysiological traits
Authors: Kieft Brandon , Li Zhou , Bryson Samuel , Hettich Robert L. , Pan Chongle , Mayali Xavier , Mueller Ryan S. 
Published: October 2021

Significance
Marine dissolved organic matter, which originates from phytoplankton, holds as much carbon as Earth’s atmosphere; yet, the biological processes governing its fate are primarily studied under idealized laboratory conditions or through indirect measures such as genome sequencing. In this work, we used isotope labeling to directly quantify uptake of complex carbon pools from the two primary sources of marine organic carbon (diatoms and cyanobacteria) by a natural microbial community. Our data show that carbon pools are partitioned into distinct microbial lineages whose physiological properties and resource acquisition strategies match the chemical nature of their preferred substrates. Our results provide ecological and functional insights into the patterns of microbial community structure changes that occur during marine phytoplankton blooms.
Identification of fluoxetine as a direct NLRP3 inhibitor to treat atrophic macular degeneration
Authors: Ambati Meenakshi , Apicella Ivana , Wang Shao-bin , Narendran Siddharth , Leung Hannah , Pereira Felipe , Nagasaka Yosuke , Huang Peirong , Varshney Akhil , Baker Kirstie L. , Marion Kenneth M. , Shadmehr Mehrdad , Stains Cliff I. , Werner Brian C. , Sadda Srinivas R. , Taylor Ethan W. , Sutton S. Scott , Magagnoli Joseph , Gelfand Bradley D. 
Published: October 2021

Significance
Dry age-related macular degeneration (AMD) affects the vision of millions of people worldwide. There is currently no Food and Drug Administration–approved treatment for dry AMD. The inflammasome components NLRP3 and ASC have been implicated in the pathogenesis of dry AMD. We report that fluoxetine, which is approved for the treatment of clinical depression, directly binds the NLRP3 protein and prevents NLRP3-ASC inflammasome assembly and activation. Fluoxetine prevents the degeneration of retinal pigmented epithelium cells in an animal model of dry AMD. We also present evidence from a big data analysis of health insurance databases that fluoxetine use is associated with reduced risk of developing dry AMD. These studies identify a potential repurposing candidate for a prevalent cause of blindness.
Cryo-EM structure determination of small proteins by nanobody-binding scaffolds (Legobodies)
Authors: Wu Xudong , Rapoport Tom A. 
Published: October 2021

Significance
Structure determination by cryo-EM is difficult or impossible to apply to proteins smaller than ∼100 kDa, excluding many membrane proteins and proteins of pharmaceutical importance from the analysis. Here, we report on a general method that allows structure determination of small proteins. The method is based on the availability of a nanobody to a target protein. The nanobody is then rigidly attached to two scaffolds: 1) a Fab fragment of an antibody directed against the nanobody and 2) a nanobody-binding protein A fragment fused to maltose binding protein and Fab-binding domains. We call the overall ensemble Legobody. The method is demonstrated for two small proteins that have sizes of ∼22 kDa.
Manufacturing and assembly of an all-glass OCT microendoscope
Authors: Taege Yanis , González-Cerdas Gerardo , Jund Felix , Zappe Hans , Ataman Çağlar 
Published: October 2021

Abstract
We present a forward-looking, fiber-scanning endomicroscope designed for optical coherence tomography (OCT) and OCT-Angiography (OCT-A) imaging through the working channel of commercial gastrointestinal endoscopes and cystoscopes. 3.4 mm in outer diameter and 11.9 mm in length, the probe is capable of high-resolution volumetric imaging with a field-of-view of up to 2.6 mm and an imaging depth of up to 1.5 mm at a lateral resolution of 19 µm. A high-precision lens mount fabricated in fused silica using selective laser-induced etching (SLE) allows the tailoring of the optical performance for different imaging requirements. A glass structure fabricated by the same method encapsulates the optical and mechanical components, providing ease of assembly and alignment accuracy. The concept can be adapted to high resolution OCT/-A imaging of various organs, particularly in the gastrointestinal tract and bladder.
Spin-orbital entangled state and realization of Kitaev physics in 3d cobalt compounds: a progress report
Authors: Kim Chaebin , Kim Heung-Sik , Park Je-Geun 
Published: October 2021

Abstract
The realization of Kitaev’s honeycomb magnetic model in real materials has become one of the most pursued topics in condensed matter physics and materials science. If found, it is expected to host exotic quantum phases of matter and offers potential realizations of fault-tolerant quantum computations. Over the past years, much effort has been made on 4d- or 5d-heavy transition metal compounds because of their intrinsic strong spin–orbit coupling. But more recently, there have been growing shreds of evidence that the Kitaev model could also be realized in 3d-transition metal systems with much weaker spin–orbit coupling. This review intends to serve as a guide to this fast-developing field focusing on systems with d
7 transition metal occupation. It overviews the current theoretical and experimental progress on realizing the Kitaev model in those systems. We examine the recent experimental observations of candidate materials with Co2+ ions: e.g., CoPS3, Na3Co2SbO6, and Na2Co2TeO6, followed by a brief review of theoretical backgrounds. We conclude this article by comparing experimental observations with density functional theory calculations. We stress the importance of inter-t
2g hopping channels and Hund’s coupling in the realization of Kitaev interactions in Co-based compounds, which has been overlooked in previous studies. This review suggests future directions in the search for Kitaev physics in 3d cobalt compounds and beyond.
Coupled electronic and magnetic relaxation in Fe1+y
Te: direct evidence for the interaction between itinerant carriers and local moments
Authors: Qian B , Liu J Y , Zhang F M , Kong F J , Zhou W , Gu Q C , Fang Y , Han Z D , Jiang X F , Zhu Y L , Wang Y , Hu J , Mao Z Q 
Published: October 2021

Abstract
Iron chalcogenides are of particular interests among iron-based superconductors due to their distinct properties such as high-T
c on FeSe monolayer and competing magnetic correlations in Fe1+y
Te. Here we report unusual transport properties observed near the critical composition of Fe1+y
Te (y ∼ 0.09) where competing magnetic correlations exist. The resistivity exhibits surprising temperature-dependent relaxation behavior below T
N, resulting in the increase of resistivity with time for 35 K < T < T
N, but the decrease of resistivity with time for 10 K < T < 35 K. Such resistivity relaxation is intimately coupled to the magnetization relaxation and can be attributed to the glassy magnetic states induced by the competing magnetic orders. These findings demonstrate strong coupling between itinerant carriers and local ordered moments in Fe1+y
Te.
Study on a new manner of the magnetization switching actuated by a unidirectional pulse current
Authors: Li K , Feng J , Yuan X , Gan L , Lu Z , Xiong R 
Published: October 2021

Abstract
A new writing scheme with a unidirectional pulse current is proposed for spin transfer torque (STT) based magnetic random-access memory (MRAM). To investigate the feasibility of the writing scheme, bilayered nano-pillars composed of a soft layer with small in-plane shape anisotropy and a hard layer with either large perpendicular anisotropy (PMA) or in-plane anisotropy (IMA) are designed and their switching behaviors are studied. It is found that in either type of bilayered nano-pillars, with the aid of the attached hard layer, the magnetization of the soft layer can be switched back and forth under a unidirectional pulse current. In an IMA/IMA nano-pillar, the magnetization of the free layer (FL) can achieve excellent alignment, which is in contrast to the IMA/PMA nano-pillar. By optimizing the dimensions and magnetic parameters of the IMA/IMA nano-pillar, a decently low switching current density (4.3 × 1011 A m−2) and ultrashort switching time (<1 ns) can be reached. Based on these results, the unidirectional writing scheme is practical if an IMA/IMA bilayer is used to replace the FL in a magnetic tunnel junction. Considering that a unidirectional writing scheme can enable the application of materials with high spin polarization such as half metals, and avoid the injection of writing current into junction using a special design, it may be very promising for STT-MRAM.
Fabrication of chitosan–alginate nanospheres for controlled release of cartap hydrochloride
Authors: Kaur Ishtpreet , Agnihotri Shekhar , Goyal Dinesh 
Published: October 2021

Abstract
Insecticide cartap hydrochloride (C) was fabricated as nanospheres by a two-step method of ionic gelification and polyelectrolyte complexation of alginate (ALG) and chitosan (CS) to undermine its adverse effects on environment. Nanospheres were characterized by field emission scanning electron microscope, Fourier transform infrared spectra and x-ray diffraction. The size of cartap hydrochloride entrapped chitosan alginate nanospheres (C-CS-ALG nps) was in range of 107.58–173.07 nm. Cartap hydrochloride nanospheres showed encapsulation efficiency of 76.19% and were stable for 30 d at ambient temperature. Release of cartap from nanospheres fitted best with first order linear kinetics followed by Hixson and Higuchi model suggesting super case II transport release. With the application of such control release nanoformulations, it is possible to reduce the frequency of field application of insecticide due to its slow release to the target organism, which is economical as well as environmentally safe.
Graphene mitigated fracture and interfacial delamination of silicon film anodes through modulating the stress generation and development
Authors: Ye Cong , Liu Bowen , Shao Jiaojing , Song Zhiwei , Zhao Weimin , Yu Zhongliang , Wang Bin 
Published: October 2021

Abstract
Silicon film is an attractive anode candidate in lithium ion batteries due to its two-dimensional (2D) morphology that is beneficial to buffer the large volume expansion of traditional silicon anodes. Even so, the generation of stress during the lithiation/delithiation process can still lead to the cracking and delamination of the silicon film from the current collector, ultimately resulting in the fast failure of the electrode. Laying a graphene layer between the silicon film and the current collector has been demonstrated to alleviate the stress generated during the battery cycling, but its universal application in commercial silicon structures with other dimensionalities remains technically challenging. Putting graphene on top of a 2D silicon film is more feasible and has also been shown with enhanced cycling stability, but the underneath mechanical mechanisms remain unclear. Herein, using the combination of 2D graphene and 2D silicon films as a model material, we investigate the stress generation and diffusion mode during the battery cycling to disclose the mechanical and electrochemical optimization of a silicon anode experimentally and theoretically. As a result, the optimum thickness of the silicon film and the coated graphene layers are obtained, and it is found the in-plane cracking and out-of-plane delamination of the silicon film could be mitigated by coating graphene due to the slow transfer of the normal and shear stresses. This work provides some understanding of the electrochemically derived mechanical behaviors of the graphene-coated battery materials and guidelines for developing stable high-energy-density batteries.
Edge harmonic oscillations in plasmas with a separatrix and the effect of edge magnetic shear
Authors: Bustos Ramirez G , Graves J P , Brunetti D 
Published: October 2021

Abstract
This work presents an extension of exfernal mode theory, where the effects of edge magnetic shear and plasma separatrix are investigated and applied to edge harmonic oscillations (EHOs). Linear analytical modelling is performed on a large aspect ratio tokamak with circular cross section, from which a set of three coupled differential equations describing the dispersion relation are derived. To correctly assess the effect of edge shear on exfernal modes, higher order corrections need to be retained in the expansion of the safety factor around the rational surface. The equations are solved numerically for equilibrium pressure and safety factor profiles containing the key features for the excitation of exfernal modes, including a model of a plasma separatrix. The current-driven branch of the instability is significantly reduced by the inclusion of the separatrix, but the mode remains unstable through coupling with the pressure-driven infernal drive. The obtained parameter space for the instability without the effect of the separatrix is compared with the growth rates calculated using the KINX code, and with the nonlinear plasma displacement calculated using the VMEC free-boundary code. From the comparison it was found that the edge shear can be of order unity and still excite exfernal modes, implying that EHOs can be excited even with weak flattening of the local safety factor at the edge, which is in line with some current experimental observations, but contrary to previous simpler analytic theory.
Laser photo-detachment combined with Langmuir probe in magnetized electronegative plasma: how the probe size affects the plasma dynamic?
Authors: Oudini N , Bendib A , Agnello R , Furno I , Taccogna F 
Published: October 2021

Abstract
Laser photo-detachment combined with a Langmuir probe (LP) is used to diagnose negative ion properties in electronegative plasmas. The technique relies on the combined use of a laser pulse and an LP. The laser pulse converts negative ions into electron–atom pairs, while the LP tracks the temporal evolution of electron current (laser photo-detachment signal) that is analyzed to retrieve the negative ion density. Although an external magnetic field is frequently used to enhance the negative ion production and extraction, the data analysis often neglects the effects of the magnetic field on the probe current. This work investigates the response of an electronegative plasma to a laser pulse in the presence of an external magnetic field through a two-dimensional particle-in-cell/Monte Carlo collision model. The results show that a low electron density region surrounding the probe, called a flux-tube, can form for a probe size comparable with or larger than the electron Larmor radius. The formation of the flux-tube strongly affects the components of the laser photo-detachment signal, leading to an important oscillation of probe current during the plateau phase, i.e. the amplitude of the AC component of the probe current is in the same magnitude order of the DC component of this current, and an important overshoot in comparison to the current rise. Numerical results are qualitatively compared to measurements obtained from the RAID negative ion source.
Challenges toward improvement of deuterium-injection power in the Large Helical Device negative-ion-based NBIs
Authors: Tsumori K. , Ikeda K. , Kisaki M. , Nakano H. , Nagaoka K. , Fujiwara Y. , Kamio S. , Osakabe M. 
Published: October 2021

Abstract
Improvement of deuterium injection power in the negative-ion-based NBIs (n-NBIs) for the Large Helical Device (LHD) are reported. Co-extracted electron current at acceleration of deuterium negative ions (D− ions) limits the injection power. The electron current is reduced by decreasing the extraction gap, and the injected D− current evaluated from the injection power increased from 46 to 55 A. Greater electron reduction was achieved by installing a structure named an ‘electron fence’ (EF), with which D− beam power was successfully improved from 2.0 MW to 3.0 MW. The injection power in three configurations − without EF, with EF of 5 mm and 7 mm distance from the plasma grid (PG) surface − have been compared in both cases of hydrogen and deuterium operations, and it was found that the configuration with the EF of 5 mm distance was the best to satisfy the performance for both of hydrogen and deuterium injections. Although the co-extracted electron current is reduced in the negative ion sources applied for JT-60SA and ITER by utilizing the PG filter, it is possible to achieve more effective electron reduction by combining the PG filter and the EF.
A geometric approximation of δ-interactions by Neumann Laplacians
Authors: Khrabustovskyi Andrii , Post Olaf 
Published: October 2021

Abstract
We demonstrate how to approximate one-dimensional Schrödinger operators with δ-interaction by a Neumann Laplacian on a narrow waveguide-like domain. Namely, we consider a domain consisting of a straight strip and a small protuberance with ‘room-and-passage’ geometry. We show that in the limit when the perpendicular size of the strip tends to zero, and the room and the passage are appropriately scaled, the Neumann Laplacian on this domain converges in generalised norm resolvent sense to the above singular Schrödinger operator. Also we prove Hausdorff convergence of the spectra. In both cases estimates on the rate of convergence are derived.
Strict Liability and Negligence with Search for Precautionary Measures
Authors: Baumann Florian , Friehe Tim 
Published: October 2021

Abstract
This article explores the performance of strict liability and negligence when agents initially have imperfect information about what care options exist to influence expected accidental harm. A technology that establishes a basic level of care is commonly known in our framework, but whether a superior one exists is uncertain. Injurers and/or victims can engage in a costly search to find out. For this setup, we show that strict liability can induce lower social costs than negligence when the superior care technology’s existence is moderately likely and agents’ search costs are high, a combination likely to apply to new and complex activities. Instead, negligence is socially preferred when the superior care technology’s existence is either very likely or very unlikely, or when search costs are low, configurations likely to apply to well-established activities.