bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of polarization- and power-dependent excitons and trions in bulk ReS2
Authors: Goo Taewon , Kim Junkyoung , Baek Dongjae , Nam Kiin , Choi Soobong , Park Seung Ryong , Bahk Young-Mi , Hong Sung Ju
Published: August 2022

We demonstrate excitons and trions in bulk ReS2 at low temperatures using polarization-resolved photoluminescence (PL) spectroscopy. At 70 K, two excitons (near 1.543 and 1.576 eV) and trions (near 1.517 and 1.570 eV) with anisotropic polarization features are observed, similar with those of a thin layer. We attribute the emergence of excitons and trions in the bulk ReS2 to its weak interlayer coupling, which is distinct from typical 2D semiconductors. Based on the assignment, we further investigate incident-laser-power dependence, providing power exponents for the quasiparticles. We expect that our basic characterization of bulk ReS2 can contribute to understand various quasiparticles and their optical applications.
Towards merged-element transmons using silicon fins: The FinMET
Authors: Goswami A. , McFadden A. P. , Zhao T. , Inbar H. , Dong J. T. , Zhao R. , McRae C. R. H. , Simmonds R. W. , Palmstrøm C. J. , Pappas D. P.
Published: August 2022

A merged-element transmon (MET) device based on silicon (Si) fins is proposed, and the first steps to form such a “FinMET” are demonstrated. This new application of fin technology capitalizes on the anisotropic etch of Si(111) relative to Si(110) to define atomically flat, high aspect ratio Si tunnel barriers with epitaxial superconductor contacts on parallel sidewall surfaces. This process circumvents the challenges associated with the growth of low-loss insulating barriers on lattice matched superconductors. By implementing low-loss, intrinsic float-zone Si as the barrier material rather than commonly used, potentially lossy AlOx, the FinMET is expected to overcome problems with standard transmons by (1) reducing dielectric losses; (2) minimizing the formation of two-level system spectral features; (3) exhibiting greater control over barrier thickness and qubit frequency spread, especially when combined with commercial fin fabrication and atomic-layer or digital etching; (4) potentially reducing the footprint by several orders of magnitude; and (5) allowing scalable fabrication. Here, as a first step to making such a device, the fabrication of Si fin capacitors on Si(110) substrates with shadow-deposited Al electrodes is demonstrated. These fin capacitors are then fabricated into lumped element resonator circuits and probed using low-temperature microwave measurements. Further thinning of silicon junctions toward the tunneling regime will enable the scalable fabrication of FinMET devices based on existing silicon technology while simultaneously avoiding lossy amorphous dielectrics for the tunnel barriers.
Predicted ferromagnetic monolayer CrSCl with large vertical piezoelectric response: A first-principles study
Authors: Guo San-Dong , Guo Xiao-Shu , Zhu Yu-Tong , Ang Yee-Sin
Published: August 2022

For two-dimensional (2D) materials, piezoelectric ferromagnetism with large out-of-plane piezoresponse is highly desirable for multifunctional ultrathin piezoelectric device application. Here, we predict that Janus monolayer CrSCl is an out-of-plane ferromagnetic semiconductor with large vertical piezoelectric response and high Curie temperature. The predicted out-of-plane piezoelectric strain coefficient d31 is −1.58 pm/V, which is higher than that of most 2D materials (compare absolute values of d31). The large out-of-plane piezoelectricity is robust against electronic correlation and biaxial strain, confirming reliability of large d31. The calculated results show that tensile strain is conducive to high Curie temperature, large magnetic anisotropy energy, and large d31. Finally, by comparing d31 of CrYX (Y = S; X = Cl, Br, I) and CrYX (Y = O; X = F, Cl, Br), we conclude that the size of d31 is positively related to electronegativity difference of X and Y atoms. Such findings can provide valuable guidelines for designing 2D piezoelectric materials with large vertical piezoelectric response.
Temperature- and pressure-dependence of the hydrogen bond network in plastic ice VII
Authors: Toffano Alberto , Russo John , Rescigno Maria , Ranieri Umbertoluca , Bove Livia E. , Martelli Fausto
Published: August 2022

We model, via classical molecular dynamics simulations, the plastic phase of ice VII across a wide range of the phase diagram of interest for planetary investigations. Although structural and dynamical properties of plastic ice VII are mostly independent on the thermodynamic conditions, the hydrogen bond network (HBN) acquires a diverse spectrum of topologies distinctly different from that of liquid water and of ice VII simulated at the same pressure. We observe that the HBN topology of plastic ice carries some degree of similarity with the crystal phase, stronger at thermodynamic conditions proximal to ice VII, and gradually lessening when approaching the liquid state. Our results enrich our understanding of the properties of water at high pressure and high temperature and may help in rationalizing the geology of water-rich planets.
Plasma metabolome and cytokine profile reveal glycylproline modulating antibody fading in convalescent COVID-19 patients
Authors: Yang Zhu , Wu Di , Lu Shanxin , Qiu Yang , Hua Zhengyi , Tan Fancheng , Zhang Cixiong , Zhang Lei , Zhang Ding-Yu , Zhou Xi , Cai Zongwei , Shang You , Lin Shu-Hai
Published: August 2022

The COVID-19 pandemic has incurred tremendous costs worldwide and is still threatening public health in the “new normal.” The association between neutralizing antibody levels and metabolic alterations in convalescent patients with COVID-19 is still poorly understood. In the present work, we conducted absolutely quantitative profiling to compare the plasma cytokines and metabolome of ordinary convalescent patients with antibodies (CA), convalescents with rapidly faded antibodies (CO), and healthy subjects. As a result, we identified that cytokines such as M-CSF and IL-12p40 and plasma metabolites such as glycylproline (gly-pro) and long-chain acylcarnitines could be associated with antibody fading in COVID-19 convalescent patients. Following feature selection, we built machine-learning–based classification models using 17 features (six cytokines and 11 metabolites). Overall accuracies of more than 90% were attained in at least six machine-learning models. Of note, the dipeptide gly-pro, a product of enzymatic peptide cleavage catalyzed by dipeptidyl peptidase 4 (DPP4), strongly accumulated in CO individuals compared with the CA group. Furthermore, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination experiments in healthy mice demonstrated that supplementation of gly-pro down-regulates SARS-CoV-2–specific receptor-binding domain antibody levels and suppresses immune responses, whereas the DPP4 inhibitor sitagliptin can counteract the inhibitory effects of gly-pro upon SARS-CoV-2 vaccination. Our findings not only reveal the important role of gly-pro in the immune responses to SARS-CoV-2 infection but also indicate a possible mechanism underlying the beneficial outcomes of treatment with DPP4 inhibitors in convalescent COVID-19 patients, shedding light on therapeutic and vaccination strategies against COVID-19.
Disorder in Ca2+ release unit locations confers
robustness but cuts flexibility of heart pacemaking
Authors: Maltsev Anna V. , Stern Michael D. , Maltsev Victor A.
Published: August 2022

Excitation–contraction coupling kinetics is dictated by the action potential rate of sinoatrial-nodal cells. These cells generate local Ca releases (LCRs) that activate Na/Ca exchanger current, which accelerates diastolic depolarization and determines the pace. LCRs are generated by clusters of ryanodine receptors, Ca release units (CRUs), residing in the sarcoplasmic reticulum. While CRU distribution exhibits substantial heterogeneity, its functional importance remains unknown. Using numerical modeling, here we show that with a square lattice distribution of CRUs, Ca-induced-Ca-release propagation during diastolic depolarization is insufficient for pacemaking within a broad range of realistic ICaL densities. Allowing each CRU to deviate randomly from its lattice position allows sparks to propagate, as observed experimentally. As disorder increases, the CRU distribution exhibits larger empty spaces and simultaneously CRU clusters, as in Poisson clumping. Propagating within the clusters, Ca release becomes synchronized, increasing action potential rate and reviving pacemaker function of dormant/nonfiring cells. However, cells with fully disordered CRU positions could not reach low firing rates and their β-adrenergic–receptor stimulation effect was substantially decreased. Inclusion of Cav1.3, a low-voltage activation L-type Ca channel isoform into ICaL, strongly increases recruitment of CRUs to fire during diastolic depolarization, increasing robustness of pacemaking and complementing effects of CRU distribution. Thus, order/disorder in CRU locations along with Cav1.3 expression regulates pacemaker function via synchronization of CRU firing. Excessive CRU disorder and/or overexpression of Cav1.3 boosts pacemaker function in the basal state, but limits the rate range, which may contribute to heart rate range decline with age and disease.
Establishing significance of gravitational-wave signals from a single observatory in the PyCBC offline search
Authors: Cabourn Davies Gareth S , Harry Ian W
Published: August 2022

Gravitational-wave observations of compact binary coalescences are allowing us to see black holes and neutron stars further into the Universe and recent results represent the most sensitive searches for compact objects ever undertaken. Most searches for gravitational waves from compact binary coalescence currently rely on detecting coincident triggers from multiple detectors. In this paper, we describe a new method for extrapolating significance of single-detector signals beyond the live-time of the analysis. Using this method, we can recover loud signals which only triggered in a single detector. We demonstrate this method in a search of O3 data, and recover seven single-detector events with a false alarm rate less than two per year. These were the same events as discovered in the GWTC-2.1 and GWTC-3 searches in a single detector, and all but one event from 3-OGC and 4-OGC. Through a campaign of injected signals, we estimate that the total time–volume sensitivity increases by a factor of up to 1.20 ± 0.02 at a false alarm rate of one per two years compared to completely ignoring single-detector events.
On the relation between asymptotic charges, the failure of peeling and late-time tails
Authors: Gajic Dejan , Kehrberger Leonhard M A
Published: August 2022

The last few years have seen considerable mathematical progress concerning the asymptotic structure of gravitational radiation in dynamical, astrophysical spacetimes. In this paper, we distil some of the key ideas from recent works and assemble them in a new way in order to make them more accessible to the wider general relativity community. In the process, we also discuss new physical findings. First, we introduce the conserved f(r)-modified Newman–Penrose charges on asymptotically flat spacetimes, and we show that these charges provide a dictionary that relates asymptotics of massless, general spin fields in different regions: asymptotic behaviour near i
+ (‘late-time tails’) can be read off from asymptotic behaviour towards

I

+

, and, similarly, asymptotic behaviour towards

I

+

can be read off from asymptotic behaviour near i
− or

I

−

. Using this dictionary, we then explain how: (I) the quadrupole approximation for a system of N infalling masses from i
− causes the ‘peeling property towards

I

+

’ to be violated, and (II) this failure of peeling results in deviations from the usual predictions for tails in the late-time behaviour of gravitational radiation: instead of the Price’s law rate

r

Ψ

[

4

]

|

I

+

∼

u

−
6

as u → ∞, we predict that

r

Ψ

[

4

]

|

I

+

∼

u

−
4

, with the coefficient of this latter decay rate being a multiple of the monopole and quadrupole moments of the matter distribution in the infinite past.
Sequential versus concurrent gradient-based optimal algorithms for the robust control of quantum systems
Authors: Dionis E , Sugny D
Published: August 2022

We investigate two different formulations of gradient-based algorithms for the robust control of quantum systems. We consider the simultaneous control of an ensemble of systems which differ by the value of a constant Hamiltonian parameter. The two versions of the iterative algorithm, called concurrent and sequential, correspond respectively to a joint update of the control at each iteration for all the elements of the ensemble or to a successive correction of the control in which the control law is different for each system. We analyze the relative efficiency of the two optimization procedures on two benchmark examples, namely the control of two-level quantum systems and Bose–Einstein condensates in a one-dimensional optical lattice. Intensive numerical simulations show the superiority of the sequential-update formulation with respect to the concurrent one for a similar numerical cost.
Laser-induced enhancement of vertical polarization in ferroelectric bilayer WTe2
Authors: Yang Qing , Song Chenchen , Meng Sheng
Published: August 2022

Light–matter interaction is one of the key means to manipulate the structural and electronic properties of materials, especially in two-dimensional (2D) layered materials, which are optically accessible due to their atomic thickness. We propose that an ultrashort laser pulse could drastically enhance the ferroelectric polarization of bilayer WTe2 by our real-time time-dependent density functional theory simulations. It is noted that bilayer WTe2 is a 2D sliding ferroelectric material recently discovered whose vertical polarization can be controlled by a slight horizontal displacement. We demonstrate that interlayer sliding and compression are simultaneously achieved upon illumination of linearly polarized near-infrared laser pulse, leading to an ultrafast electric polarization enhancement by ∼230% within hundreds of femtosecond. Two major contributions have been identified: (a) the piezoelectric effect due to laser-induced interlayer compression, caused by interlayer charge transfer and dipole-dipole interaction; (b) the interlayer sliding along the opposite direction of ferroelectric switching, induced by inhomogeneous excited carrier distribution and specific electron-phonon couplings. This work provides new insights on controlling ferroelectricity of layered materials, which may extend to other van der Waals bilayers and even bulk materials.
Nanoscale mapping of shifts in dark plasmon modes in sub 10 nm aluminum nanoantennas
Authors: Elibol Kenan , Downing Clive , Hobbs Richard G
Published: August 2022

In this work, we report the fabrication and spectroscopic characterization of subwavelength aluminum nanocavities—consisting of hexamer or tetramer clusters of sub 10 nm width Al nanorods—with tunable localized surface plasmon resonance (LSPR) energies on suspended SiN
x
membranes. Here the volume plasmon (VP) and LSPR modes of lithographically-fabricated Al nanocavities are revealed by low-loss electron energy-loss spectroscopy (EELS) in an aberration corrected scanning transmission electron microscope (STEM). We show that the existence of grain boundaries (GBs) in these nanocavities results in shifts in the VP energy and a reduction in the VP lifetime. We map the VP energy and lifetime across GBs and we observe a decrease in VP energy and lifetime at GBs that is consistent with a reduction in free carrier density and increased plasmon scattering at these locations. Dipolar LSPR modes resonant in the UV and blue regions of the electromagnetic spectrum as well as higher-energy optically dark quadrupolar and hexapolar LSPR modes are also observed and mapped by STEM and EELS. All LSPR modes are confirmed via electromagnetic simulations based on the boundary element method. Both tetramer and hexamer structures support the excitation of dipolar bright and dipolar dark modes. Finally, we find that asymmetries in fabricated nanorod hexamer and tetramer nanocavities result in a mode mixing leading to a shift in dipolar dark LSPR modes.
Measurement of the Newton’s cooling law time-constant by Arduino: an idea for STEM education in high schools
Authors: Casaburo Fausto
Published: August 2022

Commercial electronic measuring devices used in physics usually have high costs. In recent years, thanks to its low cost and the high number of available sensors, the Arduino board has been used for many educational purposes in physics education. In this paper a method to measure the Newton’s cooling law time-constant by the Arduino board is presented.
Applications of a patient-specific whole-body CT-mesh hybrid computational phantom in second cancer risk prediction
Authors: Kollitz Erika , Roew Moritz , Han Haegin , Pinto Marco , Kamp Florian , Kim Chan Hyeong , Schwarz Marco , Belka Claus , Newhauser Wayne , Parodi Katia , Dedes George
Published: August 2022

Objective. CT-mesh hybrid phantoms (or ‘hybrid(s)’) made from integrated patient CT data and mesh-type reference computational phantoms (MRCPs) can be beneficial for patient-specific whole-body dose evaluation, but this benefit has yet to be evaluated for second cancer risk prediction. The purpose of this study is to compare the hybrid’s ability to predict risk throughout the body with a patient-scaled MRCP against ground truth whole-body CTs (WBCTs). Approach. Head and neck active scanning proton treatment plans were created for and simulated on seven hybrids and the corresponding scaled MRCPs and WBCTs. Equivalent dose throughout the body was calculated and input into five second cancer risk models for both excess absolute and excess relative risk (EAR and ERR). The hybrid phantom was evaluated by comparing equivalent dose and risk predictions against the WBCT. Main results. The hybrid most frequently provides whole-body second cancer risk predictions which are closer to the ground truth when compared to a scaled MRCP alone. The performance of the hybrid relative to the scaled MRCP was consistent across ERR, EAR, and all risk models. For all in-field organs, where the hybrid shares the WBCT anatomy, the hybrid was better than or equal to the scaled MRCP for both equivalent dose and risk prediction. For out-of-field organs across all patients, the hybrid’s equivalent dose prediction was superior than the scaled MRCP in 48% of all comparisons, equivalent for 34%, and inferior for 18%. For risk assessment in the same organs, the hybrid’s prediction was superior than the scaled MRCP in 51.8% of all comparisons, equivalent in 28.6%, and inferior in 19.6%. Significance. Whole-body risk predictions from the CT-mesh hybrid have shown to be more accurate than those from a reference phantom alone. These hybrids could aid in risk-optimized treatment planning and individual risk assessment to minimize second cancer incidence.
Electron heating mode transition induced by the magnetic confinement of secondary electrons in capacitively coupled radio frequency discharges
Authors: Sun Jing-Yu , Wen Hui , Zhang Quan-Zhi , Schulze Julian , Liu Yong-Xin , Wang You-Nian
Published: August 2022

Based on particle-in-cell and test-particle simulations, an α- to γ-mode transition of the electron power absorption dynamics is found to be induced as a function of an externally applied transverse magnetic field in low pressure capacitively coupled radio frequency discharges operated in argon. This transition is caused by the increased magnetic confinement of energetic ion-induced secondary electrons (γ-electrons) at higher magnetic fields. If a transverse magnetic field is applied, γ-electrons, that are accelerated to high energies by the sheath electric field, are confined in the vicinity of the sheath. Due to their gyromotions they are returned periodically to the adjacent sheath and interact repetitively with the sheath electric field. Such confined γ-electrons are, thus, effectively multiplied by ionization collisions in the vicinity of the sheath, thereby resulting in a significant enhancement of the local ionization rate and the plasma density. In such cases, the energy coupling efficiency of γ-electrons is greatly enhanced, implying that the discharge operates in a magnetized γ-mode. Moreover, the effects of the magnetic field on ion properties and ionization dynamics at different driving frequencies and operating pressures are studied.
Parametric studies of stream instability-induced higher harmonics in plasma ionization breakdown near an emissive dielectric surface
Authors: Wen De-Qi , Zhang Peng , Krek Janez , Yangyang Fu , Verboncoeur John P
Published: August 2022

In this work, we comprehensively investigate the generation of higher harmonic (HH) electric fields normal to the applied rf electric field in multipactor-coexisting plasma breakdown by fully kinetic particle-in-cell (PIC) simulations and a theoretical model. Firstly, a base case at driving frequency 1 GHz, transverse rf electric field amplitude 3 MV m−1, and background gas pressure 0.2 Torr, is studied in detail. The enhanced harmonic frequency observed is around ten times the fundamental rf frequency, significantly lower than the Langmuir frequency. A theoretical model reveals that the fundamental mechanism of HHs generation is stream–plasma instability, which originates from stream-like secondary electron emission interacting with plasma. The resulting HH frequency and the growth rate of its oscillating amplitude from the theoretical model, agree well with the PIC simulations. With increasing pressure, the HH oscillations are found to be significantly reduced. This is because at higher pressure the gas ionization rate is higher, which causes a more rapidly increasing plasma density, leaving less time for the growth of instability. Furthermore, the parameter space in terms of background gas pressure and rf field amplitude within which the HHs appear is revealed. Finally, the effect of the driving rf frequency on HHs is also investigated, and it is found that the instability-induced oscillating HHs field remains when the driving frequency is increased to 2 GHz, however, it is highly reduced at higher driving frequency of 5 GHz, as oscillations at the fundamental frequency start playing a more important role.
Vibrational relaxation and triggering of the non-equilibrium vibrational decomposition of CO2 in gas discharges
Authors: Kotov Vladislav
Published: August 2022

Non-equilibrium vibrational dissociation CO2 → CO + O at translational–rotational temperatures T ⩽ 1200 K is investigated with semi-empiric and computational models. The governing parameter

Q
/

n

0

2

has been introduced, where Q is the specific volumetric power coupled into vibrational states and n
0 is the initial number density of CO2. It has been shown that the non-equilibrium vibrational process can only be triggered when

Q
/

n

0

2

exceeds some critical value determined by the speed of vibrational relaxation. Simple semi-empiric calculations are backed by the state-to-state simulations of the CO2 vibrational kinetics in two-modes approximation performed for conditions of microwave sustained gas discharges. The vibrational kinetics model is benchmarked against the experimental vibrational relaxation times as well as the shock tube data on the rate of the process CO2 + M → CO + O + M for M = Ar and literature data for M = CO2. At T = 300 K the estimated

Q
/

n

0

2

crit

≂
6
×
1

0

−
40

W m3 or

Q
/

p

2

crit

≂

35 W (m−
3 Pa−
2) (p is the gas pressure).

Q
/

p

2

crit

is found to always increase with increased T.
Effect of an electron beam on a dual-frequency capacitive rf plasma: experiment and simulation
*
Authors: Bogdanova M , Lopaev D , Zotovich A , Proshina O , Rakhimova T , Zyryanov S , Rakhimov A
Published: August 2022

One of the crucial challenges facing modern microelectronics is to provide plasma surface treatment at the single atomic level. To minimize defects in the underlying layers, these processes require ions with very low energies—lower than in conventional radio-frequency (rf) plasma and close to the binding energy of atoms. A conventional rf dual-frequency capacitively coupled plasma (df CCP) discharge with additional ionization by an electron beam is considered as a possible solution to this problem. This paper contains a study on the electron beam effect on 81 & 12 MHz plasma parameters such as electron energy probability function, plasma density, electron temperature and ion energy distribution at an rf-biased electrode. The experimental part of the study includes measurements carried out in an asymmetric rf df CCP discharge in Ar at 100 mTorr pressure using a Langmuir probe, a hairpin-probe, and a retarding field energy analyzer. The behavior of plasma parameters is considered in the different types of plasma: electron beam plasma, when no rf power is applied, as well as rf plasma with and without an electron beam. The 1D PIC MCC simulation is used to analyze the effect of an electron beam on the df rf plasma. The obtained results showed that the electron temperature and, accordingly, the energy of ions coming at the electrode surface can be lowered. The use of an electron beam in a df CCP discharge allows to control the plasma density, electron temperature and ion energy spectrum in the low-energy range, which can be of essential interest for atomic layer etching and atomic layer deposition technologies.
Reduced granularity in BHO-doped YBCO films on RABiTS templates
Authors: Holleis Sigrid , Shipulin Ilya A , Hühne Ruben , Bernardi Johannes , Eisterer Michael
Published: August 2022

REBCO based coated conductors (CCs) are a viable alternative to conventional superconductors for many applications, therefore the optimization of their current carrying capacity is an ongoing process. A promising route for the increase in performance is the introduction of artificial pinning centers such as BaHfO3 (BHO) nanoparticles. However, granularity still imposes a substantial performance limitation, especially in REBCO CCs deposited on RABiTS based templates, as the critical current density is severely reduced by moderate misalignment angles of adjacent grains. A combined study of scanning Hall probe microscopy and electron microscopy of undoped and BHO-doped YBa2Cu3O7-δ
(YBCO) films on technical templates shows that BHO-doping leads to a denser microstructure of the superconducting layer and higher global and local critical current densities. The statistical evaluation of local current maps allows for a quantification of the magnetic granularity where a reduction of granularity with increasing film thickness, doping and increasing temperature is found. In particular, the dependence of granularity on the film thickness and enhanced film growth through BHO-doping shows the potential for further optimization of YBCO films on RABiTS based templates.
Transport through quantum anomalous Hall bilayers with lattice mismatch
Authors: Yu Yan , Zhang Yan-Yang , Wang Si-Si , Guan Ji-Huan , Yang Xiaotian , Xia Yang , Li Shu-Shen
Published: August 2022

We theoretically investigate quantum transport properties of quantum anomalous Hall bilayers, with arbitrary ratio of lattice constants, i.e., with lattice mismatch. In the simplest case of ratio 1 (but with different model parameters in two layers), the inter-layer coupling results in resonant traversing between forward propagating waves in two layers. In the case of generic ratios, there is a quantized conductance plateau originated from two Chern numbers associated with two layers. However, the phase boundary of this quantization plateau consists of a fractal transitional region (instead of a clear transition line) of interpenetrating edge states (with quantized conductance) and bulk states (with unquantized conductance). We attribute these bulk states as mismatch induced in-gap bulk states. Different from in-gap localized states induced by random disorder, these in-gap bulk states are extended in the limit of vanishing random disorder. However, the detailed fine structure of this transitional region is sensitive to disorder, lattice structure, sample size, and even the configuration of leads connecting to it, due to the bulk and topologically trivial nature of these in-gap bulk states.
Small-scale structure in vector dark matter
Authors: Amin Mustafa A. , Jain Mudit , Karur Rohith , Mocz Philip
Published: August 2022

We investigate the differences in the small-scale structure of vector dark matter (VDM) and scalar dark matter (SDM) using 3+1 dimensional simulations of single/mul­ticomponent Schrödinger-Poisson system. We find that the amount of wave interference, core-to-halo mass ratio (and its scatter), spin of the core, as well as the shape of the central regions of dark matter halos can distinguish VDM and SDM. Starting with a collection of idealized halos (self-gravitating solitons) as an initial condition, we show that the system dynamically evolves to an approximately spherically symmetric configuration that has a core surrounded by a halo of interference patterns in the mass density. In the vector case, the central soliton in less dense and has a smoother transition to anr-3tail compared to the scalar case. As compared to SDM, wave interference in VDM is ∼ 1/√3 times smaller, resulting in fewer low and high density regions, and more diffuse granules in the halo. The ratio of VDM core mass to the total halo mass is lower than that in SDM, with a steeper dependence on the total energy of the system and a slightly larger scatter. Finally, we also initiate a study of the evolution of intrinsic spin angular momentum in the VDM case. We see a positive correlation between the total intrinsic spin in the simulation and the spin of the final central core, with significant scatter. We see large intrinsic spin in the core being possible even with vanishing amounts total angular momentum in the initial conditions (at least instantaneously). Our results point towards the possibility of distinguishing VDM from SDM using astrophysical and terrestrial observations.
Optimally-calibrated non-invasive feedback improves amputees’ metabolic consumption, balance and walking confidence
Authors: Chee Lauren , Valle Giacomo , Marazzi Michele , Preatoni Greta , Haufe Florian L , Xiloyannis Michele , Riener Robert , Raspopovic Stanisa
Published: August 2022

Objective. Lower-limb amputees suffer from a variety of health problems, including higher metabolic consumption and low mobility. These conditions are linked to the lack of a natural sensory feedback (SF) from their prosthetic device, which forces them to adopt compensatory walking strategies that increase fatigue. Recently, both invasive (i.e. requiring a surgery) and non-invasive approaches have been able to provide artificial sensations via neurostimulation, inducing multiple functional and cognitive benefits. Implants helped to improve patient mobility and significantly reduce their metabolic consumption. A wearable, non-invasive alterative that provides similar useful health benefits, would eliminate the surgery related risks and costs thereby increasing the accessibility and the spreading of such neurotechnologies. Approach. Here, we present a non-invasive SF system exploiting an optimally-calibrated (just noticeable difference-based) electro-cutaneous stimulation to encode intensity-modulated foot-ground and knee angle information personalized to the user’s just noticeable perceptual threshold. This device was holistically evaluated in three transfemoral amputees by examination of metabolic consumption while walking outdoors, walking over different inclinations on a treadmill indoors, and balance maintenance in reaction to unexpected perturbation on a treadmill indoors. We then collected spatio-temporal parameters (i.e. gait dynamic and kinematics), and self-reported prosthesis confidence while the patients were walking with and without the SF. Main results. This non-invasive SF system, encoding different distinctly perceived levels of tactile and knee flexion information, successfully enabled subjects to decrease metabolic consumption while walking and increase prosthesis confidence. Remarkably, more physiological walking strategies and increased stability in response to external perturbations were observed while walking with the SF. Significance. The health benefits observed with the use of this non-invasive device, previously only observed exploiting invasive technologies, takes an important step towards the development of a practical, non-invasive alternative to restoring SF in leg amputees.
Synchronization in phase-coupled oscillator with attractive–repulsive frequencies
Authors: Yasmine Benmesbah , Jia Wantao , Xu Yong
Published: August 2022

We investigate the synchronization behavior of a simple but quite useful mode of emergent collective behavior in ensembles of interacting dynamical elements, the Kuramoto model with attractive–repulsive frequencies features. Here, we derive a series of phase-locked (PL) states and identify the significant synchronization transition points analytically with exact boundary conditions. A detailed stability study of the model is also presented, as well as the bifurcation of the PL states set. Extremely, we show that these frequencies do not influence the stability of the system model, while the synchronization ability is considerably changed.
The second production of RSD (AC-LGAD) at FBK
Authors: Mandurrino M. , Arcidiacono R. , Bisht A. , Borghi G. , Boscardin M. , Cartiglia N. , Centis Vignali M. , Dalla Betta G.-F. , Ferrero M. , Ficorella F. , Hammad Alì O. , Martinez Rojas A.D. , Menzio L. , Pancheri L. , Paternoster G. , Siviero F. , Sola V. , Tornago M.
Published: August 2022

In this contribution we describe the second run of RSD (Resistive AC-Coupled Silicon Detectors) designed at INFN Torino and produced by Fondazione Bruno Kessler (FBK), Trento. RSD are n-in-p detectors intended for 4D particle tracking based on the LGAD technology that get rid of any segmentation implant in order to achieve the 100% fill-factor. They are characterized by three key-elements, (i) a continuous gain implant, (ii) a resistive n-cathode and (iii) a dielectric coupling layer deposited on top, guaranteeing a good spatial reconstruction of the hit position while benefiting from the good timing properties of LGADs. We will start from the very promising results of our RSD1 batch in terms of tracking performances and then we will move to the description of the design of the RSD2 run. In particular, the principles driving the sensor design and the specific AC-electrode layout adopted to optimize the signal confinement will be addressed.
Deformation and mechanics of a pulvinus-inspired material
Authors: Tadrist Loïc , Mammadi Younes , Diperi Julien , Linares Jean-Marc
Published: August 2022

Mimosa pudica rapidly folds leaves when touched. Motion is created by pulvini, ‘the plant muscles’ that allow plants to produce various complex motions. Plants rely on local control of the turgor pressure to create on-demand motion. In this paper, the mechanics of a cellular material inspired from pulvinus of M. pudica is studied. First, the manufacturing process of a cell-controllable material is described. Its deformation behaviour when pressured is tested, focusing on three pressure patterns of reference. The deformations are modelled based on the minimisation of elastic energy framework. Depending on pressurisation pattern and magnitude, reversible buckling-induced motion may occur.
Restoring habitat for fire-impacted species’ across degraded Australian landscapes
Authors: Ward Michelle , Tulloch Ayesha , Stewart Romola , Possingham Hugh P , Legge Sarah , Gallagher Rachael V , Graham Erin M , Southwell Darren , Keith David , Dixon Kingsley , Yong Chuanji , Carwardine Josie , Cronin Tim , Reside April E , Watson James E M
Published: August 2022

In the summer of 2019–2020, southern Australia experienced the largest fires on record, detrimentally impacting the habitat of native species, many of which were already threatened by past and current anthropogenic land use. A large-scale restoration effort to improve degraded species habitat would provide fire-affected species with the chance to recover and persist in burnt and unburnt habitat. To facilitate this, decision-makers require information on priority species needs for restoration intervention, the suite of potential restoration interventions, and the priority locations for applying these interventions. We prioritize actions in areas where restoration would most likely provide cost-effective benefits to priority species (defined by each species proportion of habitat burned, threat status, and vulnerability to fires), by integrating current and future species habitat suitability maps with spatially modelled costs of restoration interventions such as replanting, removing invasive species, and implementing ecologically appropriate fire management. We show that restoring the top ∼69% (112 million hectares) of the study region (current and future distributions of priority species) accounts for, on average, 95% of current and future habitat for every priority species and costs ∼AUD$73 billion yr−1 (AUD$650 hectare−1 yr−1) annualized over 30 years. This effort would include restoration actions over 6 million hectares of fire-impacted habitat, costing ∼AUD$8.8 billion/year. Large scale restoration efforts are often costly but can have significant societal co-benefits beyond biodiversity conservation. We also show that up to 291 MtCO2 (∼150 Mt DM) of carbon could be sequestered by restoration efforts, resulting in approximately AUD$253 million yr−1 in carbon market revenue if all carbon was remunerated. Our approach highlights the scale, costs, and benefits of targeted restoration activities both inside and outside of the immediate bushfire footprint over vast areas of different land tenures.
Enhanced confinement of infrared surface plasmon polaritons in borophene waveguides
Authors: Zhou Hong , Liu Guidong , Wang Lingling , Lin Qi
Published: August 2022

In this paper, a sub-wavelength terahertz plasmonic waveguide based on a borophene–insulator–metal (BIM) structure is investigated by using the 2D finite-difference time-domain method. It is proved there is a plasmonic mode of high confinement and low propagation loss in an optimized wavelength range. A dynamically adjustable filter, formed by introducing a borophene nanoribbon into the BIM waveguide, is computationally and theoretically explored, which can achieve tailoring terahertz surface plasmon polaritons in deep-subwavelength scale. These results can further provide a broader path for dynamic regulation of light transmission in the borophene-based waveguide and the development of adjustable borophene-based optoelectronic filtering.
Interface energetics make devices
Authors: Duhm Steffen
Published: August 2022

The energy-level alignment at the ubiquitous interfaces of optoelectronic devices is decisive for their performance and almost all pertinent publications include energy-level diagrams (ELDs). However, in most of these ELDs vacuum-level alignment across the complete heterojunction is assumed, which is oversimplified. On the contrary, the functioning of virtually all optoelectronic devices relies on interface phenomena like band bending, interface dipoles or potential drops. Consequently, such oversimplified ELDs do not help to understand the working mechanism of devices and have limited meaning. In this focus article, we give best practice rules for drawing ELDs: (1) give references for all the values of an ELD. (2) Mention the methods which have been used to obtain these values. (3) Add a disclaimer about the limitations of the ELD. (4) Measure as many energy levels as possible.
Development of electrochemical reactors for CO2 electroreduction—the viability of an electrochemical CO2 plant in Brazil
Authors: Nogueira Jéssica Alves , Pereira Igor Franca , Amaral Paulo Henrique Ribeiro , Miranda Caetano Rodrigues , Meneghini Júlio Romano , Lopes Thiago
Published: August 2022

Our global economy based on burning fossil fuels reached a turning point in the 2020s as problems arising from climate change are becoming increasingly evident. An important strategy to decrease anthropogenic CO2 emission relies on carbon capture and storage (CCS). However, the challenges associated with long-term storage of CO2 in the gas phase highlight the need for a viable Chemical Fixation of CO2. In this scenario, electrochemistry gains prominence since electricity from renewable sources can provide the electrons needed for CO2 electroreduction. The main drawback is the high stability of CO2, the most oxidized form of carbon. Our intention in this Perspective is to give a concise overview of CO2 electroreduction, focusing on why working in the gas phase may help overcome mass transport limitations due to the low solubility of CO2 and how the chemical environment can affect selectivity and activity. We also explore a carbon-emission analysis applied to a CO2 electrochemical system. To do so, we assumed a Brazilian scenario, that is, the carbon footprint associated with electricity generation in the country. Since Brazil relies on more renewable energy sources, an electrochemical reactor that converts CO2 to oxalate with a conversion efficiency (CE) of 20% is enough to result in CO2 abatement, that is, an oxalate production with a negative carbon footprint. Compared with the United States of America, such a system would need to operate at higher CE, 50%, to produce similar results. These results evidence how intricate the implementation of an electrochemical plant is with the carbon footprint of the electricity source.
Remote Dispensing of Emergency Release Red Blood Cells
Authors: Whiteneck Stephanie A , Lueckel Stephanie , Valente Jonathan H , King Karen A , Sweeney Joseph D
Published: August 2022

Objectives

Patients with acute bleeding are frequently transfused with emergency release (ER) group O RBCs. This practice has been reported to be safe with a low rate of acute hemolytic transfusion reactions (AHRs).

Methods

Records of patients who received ER RBCs over a 30-month period were examined at our hospitals. During this period, satellite refrigerators were on site in the emergency department (ED), which were electronically connected to the blood bank (electronically connected satellite refrigerator [ECSR]). Nurses accessing the refrigerator were required to give patient identification information, when known, prior to removal of the ER RBCs, allowing technologists the opportunity to check for previous serologic records and communicate directly with the ED if a serologic incompatibility was potentially present.

Results

In total, 935 patients were transfused with 1,847 units of ER RBCs. Thirty of these patients had a current (22/30) or historic (8/30) antibody. In 15 cases, incompatible RBCs were interdicted. In six cases, the transfusion was considered urgent, and an AHR occurred in four of these six (overall 0.4%), including one fatal AHR due to anti-KEL1.

Conclusions

Use of KEL1-negative RBCs and ECSR merits consideration as approaches to mitigate the occurrence of ER RBC-associated AHRs.
Frequency of Abnormally Low Neuropsychological Scores in Post-COVID-19 Syndrome: the Geneva COVID-COG Cohort
Authors: Voruz P , Jacot de Alcântara I , Nuber-Champier A , Cionca A , Allali G , Benzakour L , Lalive P H , Lövblad K-O , Braillard O , Nehme M , Coen M , Serratrice J , Reny J-L , Pugin J , Guessous I , Ptak R , Landis B N , Assal F , Péron J A
Published: August 2022

Objective

Several studies have reported poor long-term neuropsychological performances in patients following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but none has yet considered the effect of administering multiple intercorrelated neuropsychological tests and assessed the frequency of cognitive deficits in a normative population. Our aim was therefore to assess the presence of cumulative neuropsychological deficits in an actual post-coronavirus disease of 2019 (COVID-19) comparison group versus one simulated using Monte-Carlo methods.

Method

Validated neuropsychological Monte-Carlo simulation methods were applied to scores from a battery of neuropsychological tests (memory, executive, attentional, perceptual, logical reasoning, language, and ideomotor praxis) administered to 121 patients who had had mild, moderate, or severe COVID-19 (mean age: 56.70 years; 32% women), 222 ± 43 days post-infection. The cumulative percentages of the three severity subgroups were compared with the results of a false discovery rate-corrected probability analysis based on normative data.

Results

The cumulative percentages of deficits in memory and executive functions among the severe and moderate patients were significantly higher than those estimated for the normative population. Moderate patients also had significantly more deficits in perception and logical reasoning. In contrast, the mild group did not have significantly more cumulative deficits.

Conclusions

Moderate and severe forms of COVID-19 cause greater long-term neuropsychological deficits than those that would be found in a normative population, reinforcing the hypothesis of long-term effects of SARS-CoV-2 on cognitive function, independent of the severity of the initial infection.
Initiating Intramuscular Depot Medroxyprogesterone Acetate Increases Frequencies of Th17-like Human Immunodeficiency Virus Target Cells in the Genital Tract of Women in South Africa: A Randomized Trial
Authors: Bunjun Rubina , Ramla Tanko F , Jaumdally Shameem Z , Noël-Romas Laura , Ayele Hossaena , Brown Bryan P , Gamieldien Hoyam , Harryparsad Rushil , Dabee Smritee , Nair Gonasagrie , Onono Maricianah , Palanee-Phillips Thesla , Scoville Catilin W , Heller Kate B , Baeten Jared M , Bosinger Steven E , Burgener Adam , Passmore Jo-Ann S , Jaspan Heather , Heffron Renee
Published: August 2022

Background

Cervicovaginal CD4+ T cells are preferential targets for human immunodeficiency virus (HIV) infection and have consequently been used as a proxy measure for HIV susceptibility. The ECHO randomized trial offered a unique opportunity to consider the association between contraceptives and Th17-like cells within a trial designed to evaluate HIV risk. In a mucosal substudy of the ECHO trial, we compared the impact of initiating intramuscular depot medroxyprogesterone acetate (DMPA-IM), copper-IUD, and the levonorgestrel (LNG) implant on cervical T cells.

Methods

Cervical cytobrushes from 58 women enrolled in the ECHO trial were collected at baseline and 1 month after contraceptive initiation. We phenotyped cervical T cells using multiparameter flow cytometry, characterized the vaginal microbiome using 16s sequencing, and determined proteomic signatures associated with Th17-like cells using mass spectrometry.

Results

Unlike the LNG implant or copper-IUD, DMPA-IM was associated with higher frequencies of cervical Th17-like cells within 1 month of initiation (P = .012), including a highly susceptible, activated population co-expressing CD38, CCR5, and α4β7 (P = .003). After 1 month, women using DMPA-IM also had more Th17-like cells than women using the Cu-IUD (P = .0002) or LNG implant (P = .04). Importantly, in women using DMPA-IM, proteomic signatures signifying enhanced mucosal barrier function were associated with the increased abundance of Th17-like cells. We also found that a non–Lactobacillus-dominant microbiome at baseline was associated with more Th17-like cells post–DMPA-IM (P = .03), although this did not influence barrier function.

Conclusions

Our data suggest that DMPA-IM–driven accumulation of HIV-susceptible Th17-like cells might be counteracted by their role in maintaining mucosal barrier integrity.

Clinical Trials Registration

NCT02550067.