bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrafast entanglement switching and singlet–triplet transitions control via structured terahertz pulses
Authors: Wätzel Jonas , Berakdar Jamal , Sherman E Ya
Published: March 2022

Terahertz (THz) vector beams with spatially textured polarization are proposed to steer the spin and spatial distributions of two interacting electrons in a quantum dot. We study theoretically the spatiotemporal evolution of the spin and the charge-current densities and quantify the behavior of entanglement by calculating the concurrence. Both aspects are shown to be controllable efficiently and on the picosecond (ps) time scale by the parameters of the driving fields. Analyzing two different materials, GaAs and InGaAs, with different electron g-factors, we study the relationship between the g-factor and type of spin–orbit coupling required to produce efficient interlevel transitions. The results are useful for applications of quantum dots as basic nanoscale hardware elements in quantum information technology and for producing swiftly the appropriate spin and charge currents on demand.
A study on the influence of external magnetic field on Nitrogen RF discharge using Langmuir probe and OES methods
Authors: Mukherjee Atri , Sharma Narayan , Chakraborty M , Saha Pabitra K
Published: March 2022

This paper reports the study of the effects of an externally applied magnetic field (0–300 G), in the mode transition as well as in the radial and axial variation of different plasma parameters such as electron density, temperature, etc, in nitrogen RF discharge with the help of an RF compensated Langmuir probe (LP). Also, Optical Emission Spectroscopy (OES) study is performed in order to have a good understanding of the properties of plasma at different magnetic fields. Data collected from LP shows all three mode transitions (E, H, and W mode) in presence of magnetic fields whereas for no magnetic field only two modes (E and H) are visible. The measured value of electron density by using LP is further verified and compared theoretically using particle and power balance equations. However, the overall density profile attains a higher value for no magnetic field. This rise in overall density at 0 G field is further explained in terms of EEPF plot and OES analysis. The EEPF plot reveals that the number of high energy electrons is reduced with the application of magnetic fields. Also from OES analysis, it is found that the molecular excitations in N2 second positive system [C 3Πu (ν′) → B 3Πg (ν′′)] are increased in the presence of magnetic fields whereas with no magnetic field the ionization peak of N2 first negative system and the molecular dissociation peak at 746.8 nm attains the largest value at a certain power. Plasma density values calculated with the OES method at the different magnetic fields and RF power show a similar trend with respect to the density values obtained from the LP method.
Hierarchical chirality of biofilament induced by its chiral microstructure
Authors: Zhao Hui-Chuan , Bian Li-Chun , Zhang Tao , Tong Guo-Jun , Dai Peng-Shuai
Published: March 2022

Biological filaments with chirality are ubiquitous in biology, but the mechanism behind the chiral growth of these filaments is still unclear. To understand the formation mechanism of these chiral filaments, a hierarchical chiral model for plant tendrils is established in this work based on the Cosserat beam theory and the constitutive equation of chiral materials, which can be used to describe the deformation of chiral biological filaments. Based on this model, the bend–twist coupling chirality is considered, the chirality transfer of plant tendrils from the micro to the macro scale is derived, and the variation in the chirality coefficients with the axial strain is obtained. By introducing a pre-strain and a pre-twist deformation, a theoretical explanation for the swelling and deswelling of plant tendrils is provided as an example. Finally, based on the shooting method, the spatial configuration of plant tendrils under the action of an external force at the end load is obtained. It is found that plant tendrils can achieve regular chiral morphologies or even hierarchical chiral morphologies by adjusting their internal stresses and elastic properties. During this process, the bend–twist coupling is more critical than the stretch–twist coupling. In the presence of external loads, the chiral perversion of plant tendrils can be realized by adjusting the bend–twist coupling coefficient; however, it cannot be realized by adjusting the stretch–twist coupling coefficient. This work is of universal significance and can provide a theoretical guidance for the artificial design and performance optimization of chiral filament materials.
Enhancement in room temperature ammonia sensing performance of the La substituted SnO2 (La:SnO2) thin films developed using spray pyrolysis technique
Authors: Boomashri M , Perumal P , Vinoth S , Shkir Mohd , AlFaify S
Published: March 2022

In this report, pristine SnO2 and La doped SnO2 (La:SnO2) thin films were synthesized using the spray pyrolysis technique and their gas sensing performance operated at room temperature in the presence of ammonia (50 to 250 ppm) were analyzed. The La:SnO2 thin films were developed in four different La concentration like 0, 1, 3 & 5% in SnO2. All the prepared thin film samples were characterized using different analytical techniques for analyzing their properties. The XRD result shows the prepared La:SnO2(0, 1, 3 & 5%) thin films exhibits a tetragonal rutile structure of SnO2 without any secondary impurities according the JCPDS data (41–1445). Also, the crystallite size increases with the La doping concentration at 1% and decreases with further increase in La concentration (3 & 5%) could due to the deterioration of the grain growth of the Sn-O lattice. The scanning electron microscope (SEM) results shows the La:SnO2 thin films possess a tetragonal structures with different nano size particles and the energy dispersive x-ray analysis (EDX) confirms the presence of Sn, O & La elements. The optical results suggest that the transparency increases with the introduction of the La dopants slightly shifted towards the blue region. The bandgap of the samples increases with the increase in La concentration which is according to the Moss- Burstein effect. The photoluminescence (PL) studies confirms the 1% La:SnO2 thin films has higher defect sites due to the presence of oxygen vacancies. Finally, the gas sensing properties of the samples shows that the 1% La:SnO2 exhibits high response of 128% for 250 ppm of ammonia gas at room temperature. Also, 1% La:SnO2 possess stable current value for the fixed concentration of ammonia (250 ppm) during five cycles. This results suggests that the fabricated 1% La:SnO2 thin film sensor can be better suited for the commercial gas sensing application.
Mechanical regulation of tissues that reproduces wrinkle patterns of gastrointestinal tracts
Authors: Kai Yuto
Published: March 2022

Gastrointestinal tracts exhibit a number of surface morphologies including zigzags, labyrinths, protrusions, and invaginations that are associated with digestive functions and are suggested to be formed by mechanical mechanisms. In this study, we investigate loading conditions and mechanical properties of tissues that reproduce different wrinkle patterning of gastrointestinal tracts on cell culture platforms. Numerical simulations of wrinkling dynamics are performed for a layered model consisting of an anisotropic epithelial layer resting on a bimodular soft substrate, which in turn adheres to a rigid foundation. Motivated by the patterning of intestinal villi of chicks and mice, we examine two-step compression, where the epithelial layer is subjected to uniaxial compression followed by biaxial compression, and one-step compression, where the epithelial layer is compressed in biaxial directions. Under different mechanical conditions of tissues, a wide variety of surface patterns are displayed that reproduce luminal patterns of digestive tracts. These results suggest possible conditions for mechanical regulation of tissues to duplicate gastrointestinal surface patterns in vitro and provide insight into mechanistic understandings of biological tissues.
Investigation on multiphoton absorption in MAPbBr3 and MAPbCl3 single-crystals under excitation wavelength up to mid-infrared
Authors: Wei K H , Chen B J , Zhang L B , Zhu H R , Fan S H
Published: March 2022

The multiphoton absorption (MPA) in MAPbBr3 and MAPbCl3 single-crystals (SCs) is experimentally investigated at the excitation wavelength from near-infrared to mid-infrared. A five-photon absorption (5PA) in MAPbBr3 is demonstrated at an excitation wavelength of 2400 nm for the first time, while that in MAPbCl3 demonstrated at 2100 nm via observing fluorescence as well as using Z-scan measurement. Meanwhile, a 5PA coefficient obtained is 8.4 × 10−13 cm7 GW−4 at 2400 nm for MAPbBr3, while that of MAPbCl3 is 8.7 × 10−11 cm7 GW−4 at 2100 nm. Our results reveal that mid-infrared is available wavelength for generating high-order MPA effect in MAPbBr3 and MAPbCl3 SCs.
Probing component contributions and internal polarization in silicon-graphite composite anode for lithium-ion batteries with an electrochemical-mechanical model
Authors: Chen Yue , Guo Fuliang , Yang Lufeng , Lu Jiaze , Liu Danna , Wang Huayu , Zheng Jieyun , Yu Xiqian , Li Hong
Published: March 2022

Silicon–graphite (Si–Gr) composite anodes are attractive alternatives to replace Gr anodes for lithium-ion batteries (LIBs) owing to their relatively high capacity and mild volume change. However, it is difficult to understand electrochemical interactions of Si and Gr in Si–Gr composite anodes and internal polarization of LIBs with regular experiment methods. Herein, we establish an electrochemical-mechanical coupled model to study the effect of rate and Si content on the electrochemical and stress behavior in a Si–Gr composite anode. The results show that the composites of Si and Gr not only improve the lithiation kinetics of Gr but also alleviate the voltage hysteresis of Si and decrease the risk of lithium plating in the negative electrode. What’s more, the Si content is a tradeoff between electrode capacity and electrode volume variation. Further, various internal polarization contributions of cells using Si–Gr composite anodes are quantified by the voltage decomposition method. The results indicate that the electrochemical polarization of electrode materials and the electrolyte ohmic over-potential are dominant factors in the rate performance of cells, which provides theoretical guidance for improving the rate performance of LIBs using Si–Gr composite anodes.
Finite-key analysis of practical time-bin high-dimensional quantum key distribution with afterpulse effect
Authors: Zhou Yu , Zhou Chun , Wang Yang , Lu Yi-Fei , Jiang Mu-Sheng , Zhang Xiao-Xu , Bao Wan-Su
Published: March 2022

High-dimensional quantum resources provide the ability to encode several bits of information on a single photon, which can particularly increase the secret key rate rate of quantum key distribution (QKD) systems. Recently, a practical four-dimensional QKD scheme based on time-bin quantum photonic state, only with two single-photon avalanche detectors as measurement setup, has been proven to have a superior performance than the qubit-based one. In this paper, we extend the results to our proposed eight-dimensional scheme. Then, we consider two main practical factors to improve its secret key bound. Concretely, we take the afterpulse effect into account and apply a finite-key analysis with the intensity fluctuations. Our secret bounds give consideration to both the intensity fluctuations and the afterpulse effect for the high-dimensional QKD systems. Numerical simulations show the bound of eight-dimensional QKD scheme is more robust to the intensity fluctuations but more sensitive to the afterpulse effect than the four-dimensional one.
Radiative decays of charmed mesons in a modified relativistic quark model *
Authors: Li Jie-Lin , Chen Dian-Yong
Published: March 2022

In this study, we perform systematic estimations of the radiative decays of the charmed mesons in a modified relativistic quark model. Our estimations indicate that the branching ratios of the processes of

,

,

,

, and

are of the order of

, which are sizable to be detected experimentally. Moreover, the branching ratios of some channels, for example,

,

, and

, are estimated to be of the order of

, which may be accessible with the accumulation of data in future experiments.
Evaluation of multiple perceptual qualities of transcutaneous electrical nerve stimulation for evoked tactile sensation in forearm amputees
Authors: Zhang Jie , Hao Manzhao , Yang Fei , Liang Wenyuan , Sun Aiping , Chou Chi-Hong , Lan Ning
Published: March 2022

Objective. Evoked tactile sensation (ETS) elicited by transcutaneous electrical nerve stimulation (TENS) is promising to convey digit-specific sensory information to amputees naturally and non-invasively. Fitting ETS-based sensory feedback to amputees entails customizing coding of multiple sensory information for each stimulation site. This study was to elucidate the consistency of percepts and qualities by TENS at multiple stimulation sites in amputees retaining ETS. Approach. Five transradial amputees with ETS and fourteen able-bodied subjects participated in this study. Surface electrodes with small size (10 mm in diameter) were adopted to fit the restricted projected finger map on the forearm stump of amputees. Effects of stimulus frequency on sensory types were assessed, and the map of perceptual threshold for each sensation was characterized. Sensitivity for vibration and buzz sensations was measured using distinguishable difference in stimulus pulse width. Rapid assessments for modulation ranges of pulse width at fixed amplitude and frequency were developed for coding sensory information. Buzz sensation was demonstrated for location discrimination relating to prosthetic fingers. Main results. Vibration and buzz sensations were consistently evoked at 20 Hz and 50 Hz as dominant sensation types in all amputees and able-bodied subjects. Perceptual thresholds of different sensations followed a similar strength-duration curve relating stimulus amplitude to pulse width. The averaged distinguishable difference in pulse width was 12.84 ± 7.23 μs for vibration and 15.21 ± 6.47 μs for buzz in able-bodied subjects, and 14.91 ± 10.54 μs for vibration and 11.30 ± 3.42 μs for buzz in amputees. Buzz coding strategy enabled five amputees to discriminate contact of individual fingers with an overall accuracy of 77.85%. Significance. The consistency in perceptual qualities of dominant sensations can be exploited for coding multi-modality sensory feedback. A fast protocol of sensory coding is possible for fitting ETS-based, non-invasive sensory feedback to amputees.
Epileptic seizure prediction using spectral width of the covariance matrix
Authors: EPMoghaddam Dorsa , Sheth Sameer A , Haneef Zulfi , Gavvala Jay , Aazhang Behnaam
Published: March 2022

Objective.Epilepsy is a common neurological disorder in which patients suffer from sudden and unpredictable seizures. Seizures are caused by excessive and abnormal neuronal activity. Different methods have been employed to investigate electroencephalogram (EEG) data in patients with epilepsy. This paper introduces a simple yet accurate array-based method to study and predict seizures.Approach.We use the CHB-MIT dataset (all 24 cases), which includes scalp EEG recordings. The proposed method is based on the random matrix theory. After applying wavelet decomposition to denoise the data, we analyze the spatial coherence of the epileptic recordings by looking at the width of the covariance matrix eigenvalue distribution at different time and frequency bins.Main results.We train patient-specific support vector machine classifiers to distinguish between interictal and preictal data with high performance and a false prediction rate as low as 0.09 h−1. The proposed technique achieves an average accuracy, specificity, sensitivity, and area under the curve of 99.05%, 93.56%, 99.09%, and 0.99, respectively.Significance.Our proposed method outperforms state-of-the-art works in terms of sensitivity while maintaining a low false prediction rate. Also, in contrast to neural networks, which may achieve high performance, this work provides high sensitivity without compromising interpretability.
Resistance distance distribution in large sparse random graphs
Authors: Akara-pipattana Pawat , Chotibut Thiparat , Evnin Oleg
Published: March 2022

We consider an Erdős–Rényi random graph consisting of N vertices connected by randomly and independently drawing an edge between every pair of them with probability c/N so that at N → ∞ one obtains a graph of finite mean degree c. In this regime, we study the distribution of resistance distances between the vertices of this graph and develop an auxiliary field representation for this quantity in the spirit of statistical field theory. Using this representation, a saddle point evaluation of the resistance distance distribution is possible at N → ∞ in terms of an 1/c expansion. The leading order of this expansion captures the results of numerical simulations very well down to rather small values of c; for example, it recovers the empirical distribution at c = 4 or 6 with an overlap of around 90%. At large values of c, the distribution tends to a Gaussian of mean 2/c and standard deviation

2
/

c

3

. At small values of c, the distribution is skewed toward larger values, as captured by our saddle point analysis, and many fine features appear in addition to the main peak, including subleading peaks that can be traced back to resistance distances between vertices of specific low degrees and the rest of the graph. We develop a more refined saddle point scheme that extracts the corresponding degree-differentiated resistance distance distributions. We then use this approach to recover analytically the most apparent of the subleading peaks that originates from vertices of degree 1. Rather intuitively, this subleading peak turns out to be a copy of the main peak, shifted by one unit of resistance distance and scaled down by the probability for a vertex to have degree 1. We comment on a possible lack of smoothness in the true N → ∞ distribution suggested by the numerics.
Hydrodynamics and transport in the long-range-interacting φ
4 chain
Authors: Iubini Stefano , Lepri Stefano , Ruffo Stefano
Published: March 2022

We present a simulation study of the one-dimensional φ
4 lattice theory with long-range interactions decaying as an inverse power r
−(1+σ) of the intersite distance r, σ > 0. We consider the cases of single and double-well local potentials with both attractive and repulsive couplings. The double-well, attractive case displays a phase transition for 0 < σ ⩽ 1 analogous to the Ising model with long-range ferromagnetic interactions. A dynamical scaling analysis of both energy structure factors and excess energy correlations shows that the effective hydrodynamics is diffusive for σ > 1 and anomalous for 0 < σ < 1, where fluctuations propagate superdiffusively. We argue that this is accounted for by a fractional diffusion process and we compare the results with an effective model of energy transport based on Lévy flights. Remarkably, this result is fairly insensitive on the phase transition. Nonequilibrium simulations with an applied thermal gradient are in quantitative agreement with the above scenario.
The Microstrip Silicon Detector (MSD) data acquisition system architecture for the FOOT experiment
Authors: Kanxheri K. , Barbanera M. , Ambrosi G. , Silvestre G. , Biondi S. , Ridolfi R. , Villa M. , Aisa D. , Caprai M. , Ionica M. , Placidi P. , Servoli L.
Published: March 2022

The FOOT (FragmentatiOn Of Target) multi-detector experiment aims at improving the accuracy of oncological hadrontherapy for tumor treatment. It studies the nuclear fragmentation due to the interactions of charged particle beams with patient tissues employing the inverse kinematic approach to boost the fragments in the laboratory reference system. Hence it is necessary a tracking system in a magnetic field to measure the momentum of the charged fragments. The Microstrip Silicon Detector (MSD) is part of the charged-ions-tracking magnetic spectrometer for the evaluation of the Linear Energy Transfer LET (dE/dx) and the nuclear fragments momentum. Here we describe the MSD architecture and its data acquisition system whose task is to collect and digitize the detectors output, generating a data packet to be sent to the experiment’s central acquisition. This data acquisition system is designed and tested to withstand the trigger rate and detector’s throughput; it has a small size and is easily portable, a necessary feature for an experiment that will move among the available ion beam accelerators and proton therapy treatment rooms.
Recent development of neutron and energetic-particle diagnostics for LHD deuterium discharges
Authors: Isobe M. , Ogawa K. , Sangaroon S. , Kamio S. , Fujiwara Y. , Osakabe M.
Published: March 2022

An integrated set of neutron diagnostics developed for the deuterium operation of the Large Helical Device (LHD) has been revealing behavior of energetic ions in three-dimensional plasmas, together with energetic-particle diagnostics. In order to obtain deeper understanding of physics related to energetic ions in the LHD, development of plasma diagnostics that can provide energy distribution of energetic ions is now being accelerated. Recent advances in development of the D-D neutron energy spectrometer, a neutral particle analyzer based on a single-crystal chemical vapor deposition diamond, and a tangential fast-ion Dα diagnostic for deuterium discharges of the LHD are described.
Prototype of readout electronics for GAEA gamma spectrometer of Back-n facility at CSNS
Authors: Xie L. , Cao P. , Yu T. , Jiang Z. , An Q. , Li J. , Li C. , Wu X. , Wang Z. , Bai H. , Bai J. , Bao J. , Chen Q. , Chen Y. , Chen Z. , Cui Z. , Fan A. , Fan R. , Feng C. , Feng F. , Gao K. , Gu M. , Han C. , Han Z. , He G. , He Y. , Hong Y. , Hu Y. , Huang H. , Jia W. , Jiang H. , Jiang W. , Jin Z. , Kang L. , Li B. , Li G. , Li Q. , Li X. , Li Y. , Liu J. , Liu R. , Liu S. , Luan G. , Ning C. , Qi B. , Ren J. , Ren Z. , Ruan X. , Song Z. , Sun K. , Tan Z. , Tang J. , Tang S. , Wang L. , Wang P. , Wen Z. , Wu X. , Yang Y. , Yi H. , Yu Y. , Zhang G. , Zhang L. , Zhang M. , Zhang Q. , Zhang X. , Zhang Y. , Zhang Y. , Zhang Z. , Zhao M. , Zhou L. , Zhou Z. , Zhu K.
Published: March 2022

The back-streaming neutrons (Back-n) facility at China
Spallation Neutron Source (CSNS) provides an excellent white neutron
source for accurate nuclear data measurements. At Back-n, the GAmma
spectrometer with GErmanium Array (GAEA) in planning is designed to
measure neutron-induced cross-sections, nuclear structure, and
in-beam nuclear spectroscopy. As GAEA consists of various detectors,
developing and maintaining the readout electronics for this
spectrometer is challenging. A prototype of readout electronics
based on the universal digital readout platform is proposed in this
paper. The digitizer in the platform consists of a data processing
carrier and a signal acquire mezzanine. Different mezzanines are
designed to accommodate various detectors in GAEA. The carrier's
firmware also has a universal part for data readout and a
reconfigurable module for real-time data processing. In order to
synchronize all digitizers, a time synchronization module is
designed, based upon which a global synchronous network is
constructed with PXIe chassis. Critical signals as the clock,
trigger, and control can be synchronously distributed over this
network with high precision, significantly simplifying the whole
readout electronics. Several tests were carried out to evaluate the
prototype. The measured FWHM of the 22Na characteristic peak at
1274.5 keV is better than 0.15% for the HPGe detector. The
measured time resolution of the readout electronics is
34.7 ps. Test results show that the performance of the readout
electronics can meet GAEA requirements.
Hybrid fabrication of photo-clickable vascular hydrogels with additive manufactured titanium implants for enhanced osseointegration and vascularized bone formation
Authors: Li Jun , Cui Xiaolin , Lindberg Gabriella C J , Alcala-Orozco Cesar R , Hooper Gary J , Lim Khoon S , Woodfield Tim B F
Published: March 2022

Bone regeneration of critical-sized bone defects, bone fractures or joint replacements remains a significant clinical challenge. Although there has been rapid advancement in both the fields of bone tissue engineering and additive manufacturing, functional bone implants with rapid vascularization capacity to ensure osseointegration and long-term biological fixation in large bone defects remains limited in clinics. In this study, we developed an in vitro vascularized bone implant by combining cell-laden hydrogels with direct metal printed (DMP) porous titanium alloys (Ti–6Al–4V). A 5 wt% allylated gelatin (GelAGE), was utilized to co-encapsulate human mesenchymal stromal cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) to investigate concurrent osteogenic and vasculogenic performance. DMP macro-porous Ti–6Al–4V scaffolds were subsequently infused/enriched with cell-laden GelAGE to examine the feasibility to deliver cells and engineer vascular-like networks in the hybrid implant. Furthermore, as a proof of concept, a full-scale porous Ti–6Al–4V acetabular cup was impregnated with cell-laden hydrogel to validate the clinical potential of this strategy. The vasculogenic potential was evaluated by examining micro-capillary formation coupled with capillary network maturation and stabilization. Osteogenic differentiation was assessed via alkaline phosphatase activity as well as osteocalcin and osteopontin expression. Our results suggested that GelAGE supported HUVECs spreading and vascular-like network formation, along with osteogenesis of hMSCs. Titanium hybrid constructs with cell-laden hydrogel demonstrated enhanced osteogenesis with similar vasculogenic capability compared to the cell-laden hydrogel alone constructs. The full-scale implant with cell-laden hydrogel coating similarly showed cell distribution and spreading, implying the potential for further clinical application. Our study presents the feasibility of integrating bio-functional hydrogels with porous titanium implants to fabricate a vascularized hybrid construct with both mechanical support and preferable biological functionality (osteogenesis/vasculogenesis), which paves the way for improved strategies to enhance bone regeneration in complex large bone defects achieving long-term bone-implant fixation.
Investigation of the mechanical and thermal stability of ultra-high molecular weight polyethylene by using amide-multi-walled carbon nanotubes as a reinforcement material
Authors: Makableh Yahia , Bozeya Ayat , Rawashdeh Tariq , Alnasra Ibrahim , Hammam Haneen Abu
Published: March 2022

In this research, an investigation of the thermal and mechanical properties of ultra-high molecular weight polyethylene (UHMWPE) reinforced with pristine and modified multi- walled carbon nanotubes (Amide-MWCNTs)-MWCNTs nanocomposite was conducted. The nanocomposites were prepared by ultra-sonication mixing and hot press moulding methods. The MWCNTs surface was functionalised with amide group. The prepared nanocomposites were characterised based on structure, thermal, and mechanical properties by x-ray diffraction (XRD), differential scanning calorimeter (DSC), and universal testing machine, respectively. The crystallinity, crystal size, space between atomic lattice and lattice constant were calculated from the XRD patterns. Results showed the decrease in UHMWPE crystallinity without affecting the crystal structure of UHMWPE when adding pristine MWCNTs and Amide-MWCNTs (1−5 wt%). Tensile test results showed an increase in the composites stiffness for all percentages in the range of 19%–65%, while the elongation at break for the 3 wt% Amide-MWCNT nanocomposite increased up to 71%. This indicates that the interfacial adhesion was enhanced by the amide group.
Synergistic effects of Piper longum mediated MgO nanoparticles for bacterial and fungal inhibition
Authors: Bakri Marwah
Published: March 2022

A simple, cost-efficient green synthesis has been reported in the present study to synthesise and study the antimicrobial activity of the Piper longum assisted magnesium oxide nanoparticles (MgO-NPs). The MgO nanoparticles were prepared by co-precipitation method and characterised by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and ultraviolet visible absorption spectroscopy (UV-vis), energy dispersive x-ray (EDX) and transmission electron microscopy (TEM) analysis. The XRD study represents the FCC lattice of MgO- NPs. The adsorption of polyphenols and proteins in the P.longum extract on the surface of the prepared MgO-NPs was identified by FTIR. HR-TEM shows spherical particles with average size 22.67 nm due to the sufficient amount of capping. The energy band gap for MgO-NPs was found to be 5.1 eV. The optical studies indicate the quantum confinement effect of magnesium oxide NPs prepared with increasing concentration of Piper longum. The results indicated that small particle sized MgO-NPs have improved antimicrobial activity towards Pseudomonas aeruginosa, Staphylococcus aureus and Aspergillus flavus. The functional activities of the Piper longum assisted magnesium oxide NPs were influenced largely by the particle size. The obtained results revealed that the green synthesised MgO-NPs demonstrated assuring biomedical potentials.
Harmonization of technical image quality in computed tomography: comparison between different reconstruction algorithms and kernels from six scanners
Authors: Juntunen Mikael A K , Rautiainen Jari , Hänninen Nina E , Kotiaho Antti O
Published: March 2022

Purpose. The radiology department faces a large number of reconstruction algorithms and kernels during their computed tomography (CT) optimization process. These reconstruction methods are proprietary and ensuring consistent image quality between scanners is becoming increasingly difficult. This study contributes to solving this challenge in CT image quality harmonization by modifying and evaluating a reconstruction algorithm and kernel matching scheme. Methods. The Catphan 600 phantom was scanned with six different CT scanners from four vendors. The phantom was scanned with volumetric CT dose indices (CTDIvols) of 10 mGy and 40 mGy, and the data were reconstructed using 1 mm and 5 mm slices with each combination of reconstruction algorithm, body region kernel, and iterative and deep learning reconstruction strength. A matching scheme developed in previous research, which utilizes the noise power spectrum (NPS) and modulation transfer function (MTF), was modified based on our organization’s needs and used to identify the matching reconstruction algorithms and kernels between different scanners. Results. The matching paradigm produced good matching results, and the mean ± standard deviation (median) matching function values for the different acquisition settings were (a value of 1 indicates a perfect match): CTDIvol 10 mGy, 1 mm slice: 0.78 ± 0.31 (0.94); CTDIvol 10 mGy, 5 mm slice: 0.75 ± 0.33 (0.93); CTDIvol 40 mGy, 1 mm slice: 0.81 ± 0.28 (0.95); CTDIvol 40 mGy, 5 mm slice: 0.75 ± 0.33 (0.93). In general, soft reconstruction kernels, i.e., noise-reducing kernels that reduce sharpness, of one vendor were matched with the soft kernels of another vendor, and vice versa for sharper kernels. Conclusions. Combined quantitative assessment of NPS and MTF allows effective strategy for harmonization of technical image quality between different CT scanners. A software was also shared to support CT image quality harmonization in other institutions.
Reentry in cardiac ventricular epicardial tissue due to SCN5A L812Q gene mutation: a computational study
Authors: Satish Helan , Reddy M Ramasubba
Published: March 2022

Cardiovascular diseases are the major cause of sudden death. Brugada syndrome is an inherited rare disease, that leads to death due to ventricular fibrillation (VF). Brugada Syndrome is related to mutations in the genes that encode SCN5A, a subunit of sodium ion channel (NaV). This computational study investigates the mechanism of loss of function gene mutation (SCN5A L812Q) in sodium ion channel that leads to spiral wave and further develops into VF in an epicardial tissue with homozygous condition. Study was made on wild type, L812Q heterozygous mutated and homozygous mutated ventricular tissues. Ten Tusscher human ventricular cell model (TP06) was used for the simulation study. VF is developed when a spiral wave that causes ventricular arrhythmia breaks. This leads to the formation of multiple spiral waves that are activated on different regions of the ventricles called wave break. This is observed in the epicardial tissue with homozygous condition as the effect of SCN5A L812Q gene mutation. This indicates that VF occurs in the SCN5A L812Q gene mutated homozygous ventricular epicardial tissue that may further lead to Brugada syndrome.
Simulation studies of tungsten impurity behaviors during neon impurity seeding with tungsten bundled charge state model using SOLPS-ITER on EAST
Authors: GAO Shanlu , LIU Xiaoju , DENG Guozhong , MING Tingfeng , LI Guoqiang , ZHANG Xuexi , WU Xiaodong , WU Xiaohe , LI Bang , FAN Haochen , GAO Xiang
Published: March 2022

An investigation into tungsten (W) impurity behaviors with the update of the EAST lower W divertor for H-mode has been carried out using SOLPS-ITER. This work aims to study the effect of external neon (Ne) impurity seeding on W impurity sputtering with the bundled charge state model. As the Ne seeding rate increases, plasma parameters, W concentration (

C

W

), and eroded W flux (

Γ

W

Ero

) at both targets are compared and analyzed between the highly resolved bundled model ‘jett’ and the full W charge state model. The results indicate that ‘jett’ can produce divertor behaviors essentially in agreement with the full W charge state model. The bundled scheme with high resolution in low W charge states (<W20+) has no obvious effect on the Ne impurity distribution and thus little effect on W sputtering by Ne. Meanwhile, parametric scans of radial particle and thermal transport diffusivities (

D

⊥

and

χ

e
,
i

) in the SOL are simulated using the ‘jett’ bundled model. The results indicate that the transport diffusivity variations have significant influences on the divertor parameters, especially for W impurity sputtering.
Thermal release tape-assisted semiconductor membrane transfer process for hybrid photonic devices embedding quantum emitters
Authors: Haws Cori , Guha Biswarup , Perez Edgar , Davanco Marcelo , Song Jin Dong , Srinivasan Kartik , Sapienza Luca
Published: March 2022

The ability to combine different materials enables a combination of complementary properties and device engineering that cannot be found or exploited within a single material system. In the realm of quantum nanophotonics, one might want to increase device functionality by, for instance, combining efficient classical and quantum light emission available in III–V semiconductors, low-loss light propagation accessible in silicon-based materials, fast electro-optical properties of lithium niobate, and broadband reflectors and/or buried metallic contacts for local electric field application or electrical injection of emitters. However, combining different materials on a single wafer is challenging and may result in low reproducibility and/or low yield. For instance, direct epitaxial growth requires crystal lattice matching for producing of defect-free films, and wafer bonding requires considerable and costly process development for high bond strength and yield. We propose a transfer printing technique based on the removal of arrays of free-standing membranes and their deposition onto a host material using a thermal release adhesive tape-assisted process. This approach is versatile, in that it poses limited restrictions on the transferred and host materials. In particular, we transfer 190 nm-thick GaAs membranes that contain InAs quantum dots and which have dimensions up to about 260 μm × 80 μm onto a gold-coated silicon substrate. We show that the presence of a back reflector combined with the etching of micropillars significantly increases the extraction efficiency of quantum light from a single quantum dot line, reaching photon fluxes exceeding 8 × 105 photons per second. This flux is four times higher than the highest count rates measured from emitters outside the pillars on the same chip. Given its versatility and ease of processing, this technique provides a path to realising hybrid quantum nanophotonic devices that combine virtually any material in which free-standing membranes can be made onto any host substrate, without specific compatibility issues and/or requirements.
Homological invariants of the arrow removal operation
Authors: Erdmann Karin , Psaroudakis Chrysostomos , Solberg Øyvind
Published: March 2022

In this paper we show that Gorensteinness, singularity categories and the finite generation condition Fg for the Hochschild cohomology are invariants under the arrow removal operation for a finite dimensional algebra.
Toric eigenvalue methods for solving sparse polynomial systems
Authors: Bender Matías , Telen Simon
Published: March 2022

We consider the problem of computing homogeneous coordinates of points in a zero-dimensional subscheme of a compact, complex toric variety

X
X

. Our starting point is a homogeneous ideal

I
I

in the Cox ring of

X
X

, which in practice might arise from homogenizing a sparse polynomial system. We prove a new eigenvalue theorem in the toric compact setting, which leads to a novel, robust numerical approach for solving this problem. Our method works in particular for systems having isolated solutions with arbitrary multiplicities. It depends on the multigraded regularity properties of

I
I

. We study these properties and provide bounds on the size of the matrices in our approach when

I
I

is a complete intersection.
Time integrators for dispersive equations in the long wave regime
Authors: Cabrera Calvo María , Rousset Frédéric , Schratz Katharina
Published: March 2022

We introduce a novel class of time integrators for dispersive equations which allow us to reproduce the dynamics of the solution from the classical

ε
=
1

\varepsilon = 1

up to long wave limit regime

ε
≪
1

\varepsilon \ll 1

on the natural time scale of the PDE

t
=

O

(

1
ε

)

t= \mathcal {O}(\frac {1}{\varepsilon })

. Most notably the global error of our new schemes is of order

τ
ε

\tau \varepsilon

(for the first-order scheme) and

τ
2

ε

\tau ^2 \varepsilon

(for the second-order scheme) on time intervals of length

O

(

1
ε

)

\mathcal {O}\left ( \frac {1}{\varepsilon }\right )

.
On the 𝑞-analogue of the Pair Correlation Conjecture via Fourier optimization
Authors: Quesada-Herrera Oscar
Published: March 2022

We study the

q
q

-analogue of the average of Montgomery’s function

F
(
α
,

T
)

F(\alpha ,\, T)

over bounded intervals. Assuming the Generalized Riemann Hypothesis for Dirichlet

L
L

-functions, we obtain upper and lower bounds for this average over an interval that are quite close to the pointwise conjectured value of

1
1

. To compute our bounds, we extend a Fourier analysis approach by Carneiro, Chandee, Chirre, and Milinovich, and apply computational methods of non-smooth programming.
Toric promotion
Authors: Defant Colin
Published: March 2022

This article introduces toric promotion as a cyclic analogue of Schützenberger’s promotion operator. Toric promotion acts on the set of labelings of a graph

G
G

. We discuss connections between toric promotion and previously-studied notions such as toric posets and friends-and-strangers graphs. Our main theorem provides a surprisingly simple description of the orbit structure of toric promotion when

G
G

is a forest.
Extension complexity of low-dimensional polytopes
Authors: Kwan Matthew , Sauermann Lisa , Zhao Yufei
Published: March 2022

Sometimes, it is possible to represent a complicated polytope as a projection of a much simpler polytope. To quantify this phenomenon, the extension complexity of a polytope

P
P

is defined to be the minimum number of facets of a (possibly higher-dimensional) polytope from which

P
P

can be obtained as a (linear) projection. This notion is motivated by its relevance to combinatorial optimisation, and has been studied intensively for various specific polytopes associated with important optimisation problems. In this paper we study extension complexity as a parameter of general polytopes, more specifically considering various families of low-dimensional polytopes.

First, we prove that for a fixed dimension

d
d

, the extension complexity of a random

d
d

-dimensional polytope (obtained as the convex hull of random points in a ball or on a sphere) is typically on the order of the square root of its number of vertices. Second, we prove that any cyclic

n
n

-vertex polygon (whose vertices lie on a circle) has extension complexity at most

24

n

24\sqrt n

. This bound is tight up to the constant factor

24
24

. Finally, we show that there exists an

n

o
(
1
)

n^{o(1)}

-dimensional polytope with at most

n
n

vertices and extension complexity

n

1
−
o
(
1
)

n^{1-o(1)}

. Our theorems are proved with a range of different techniques, which we hope will be of further interest.
Remarks on the Bernstein inequality for higher order operators and related results
Authors: Li Dong , Sire Yannick
Published: March 2022

This note is devoted to several results about frequency localized functions and associated Bernstein inequalities for higher order operators. In particular, we construct some counterexamples for the frequency-localized Bernstein inequalities for higher order Laplacians. We show also that the heat semi-group associated to powers larger than one of the laplacian does not satisfy the strict maximum principle in general. Finally, in a suitable range we provide several positive results.
The value of qualitative data in Quality Improvement Projects in the care of older adults: the case of frailty scores in the emergency department
Authors: Pascall Jones Paul , Tomkow Louise
Published: March 2022

This commentary discusses the role and value of qualitative data when undertaking quality improvement (QI) focussing on the care of older adults. To illustrate this, we reflect on our own experiences of planning a QI project to improve the documentation of Clinical Frailty Scale (CFS) scores in the emergency department (ED) during the coronavirus disease of 2019 (COVID-19) pandemic. National clinical guidance for COVID-19 states that all adults over the age of 65 should be given a CFS at the first point of contact during hospital admission. Therefore, there is a need to improve CFS documentation, specifically in acute care settings.

We describe how qualitative methods facilitated an understanding of the barriers to CFS documentation in ED. Staff see the CFS as a useful tool for inter-professional communication, though there are tensions between clinical guidance and their beliefs. Staff had moral concerns about how an ED-allocated CFS might limit available treatment options for older adults. Our findings demonstrate how qualitative methods can illuminate the important social and moral dimensions of why improvement does or does not occur.
Primary Central Nervous System Anaplastic Large Cell Lymphoma, ALK Positive
Authors: Ahrendsen Jared T , Ta Robert , Li Jingwei , Weinberg Olga K , Ferry Judith A , Hasserjian Robert P , Meredith David M , Varma Hemant , Sadigh Sam , Michaels Phillip D
Published: March 2022

Objectives

Primary central nervous system anaplastic large cell lymphoma, anaplastic lymphoma kinase positive (primary CNS ALCL, ALK+) is a rare CNS lymphoma whose description is limited to case reports. These tumors have a variable clinical course, and prognosis is primarily determined by age. We present the largest case series to date of primary CNS ALCL, ALK+, with observational data.

Methods

A retrospective search of multiple academic centers was performed to identify cases of primary CNS ALCL, ALK+. We also performed a review of published cases of primary CNS ALCL, ALK+. Clinical history, radiography, pathology, and genetic testing data were obtained to determine the prognostic implications in the context of clinical course.

Results

We identified three cases of primary CNS ALCL, ALK+ from our databases. A literature review identified 30 published reports of 31 individual cases. Clinical features for the combined 34 cases included a median age of 18.5 years, with a male to female ratio of 4.7:1, and the most common symptom was headache. Genetic studies demonstrated an ALK rearrangement by fluorescence in situ hybridization, and a gene fusion assay confirmed an NPM1-ALK gene fusion in one case.

Conclusions

We present the largest case series to date of a rare primary CNS lymphoma with additional diagnostic and clinical information.
Leaf surface traits contributing to wettability, water interception and uptake of above-ground water sources in shrubs of Patagonian arid ecosystems
Authors: Cavallaro Agustín , Carbonell-Silletta Luisina , Burek Antonella , Goldstein Guillermo , Scholz Fabián G , Bucci Sandra J
Published: March 2022

Background and Aims

The ecohydrological significance of leaf wetting due to atmospheric water in arid and semiarid ecosystems is not well understood. In these environments, the inputs of precipitation or dew formation resulting in leaf wetting have positive effects on plant functioning. However, its impact on plant water relations may depend on the degree of leaf surface wettability. In this study we evaluated leaf wettability and other leaf traits and its effects on foliar water uptake and canopy interception in plant species of a Patagonian steppe. We also studied how leaf traits affecting wettability vary seasonally from growing to dry season.

Methods

Contact angle of a water droplet with the leaf surface, water adhesion, droplet retention angle, stomatal density, cuticular conductance, canopy interception and maximum foliar water uptake were determined in six dominant shrub species.

Key results

All species increased leaf wettability during the dry season and most species were considered highly wettable. The leaf surface had very high capacity to store and retain water. We found a negative correlation between foliar water uptake and leaf hydrophilia.

Conclusions

Despite the diversity of life forms, including cushion shrubs and tall shrubs, as well as phenological variability, all species converged in similar seasonal changes in leaf traits that favour wettability. Intercepted water by crowns and the extremely high capacity of retention of droplets on leaf surfaces can have a significant impact on eco-hydrological process in water limited ecosystems where most of water sources during the growing and the dry season may be small rainfall events or dew, which do not always increase soil water availability.