bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of the thermoelectric power factor in monolayer PbBiI: staggered exchange field effect
Authors: Phuong Le T. T. , Phong Tran C. , Hoi Bui D. , Yarmohammadi Mohsen
Published: July 2022

The thermopower is enhanced 133% through highly dispersive and degenerate energy bands resulting from the staggered exchange field.
Construction of Ru/FeCoP heterointerface to drive dual active site mechanism for efficient overall water splitting
Authors: Wang Yilin , Du Yunmei , Fu Ziqi , Ren Jinhong , Fu Yunlei , Wang Lei
Published: July 2022

The water-splitting efficiency is improved by Ru/FeCoP heterointerface to drive dual-active site mechanism. The η100 of Ru@FeCoP are 0.0741 V for HER and 0.314 V for OER, which is reduced by 63.8% and 55.2% over Pt/C and RuO2, respectively.
Lignin-derived porous graphene for wearable and ultrasensitive strain sensors
Authors: Yang Shuhong , Ling Yun , Wu Qian , Zhang Hanwen , Yan Zheng , Huang Guoliang , Lin Jian , Wan Caixia
Published: July 2022

Synopsis: Lignin transformed into porous graphene via direct laser writing for wearable and ultrasensitive strain sensors for human motion monitoring.
Multi-functional hybrid perovskites with triple-channel switches and optical properties
Authors: Lun Meng-Meng , Zhou Fo-Ling , Fu Da-Wei , Ye Qiong
Published: July 2022

Triple-channel (dielectric/SHG/PL) switches with a one-dimensional perovskite structure are successfully obtained through the halogen substitution strategy. This work might inspire the further exploration of multi-functional switching materials.
Efficient M-shaped blue emitters having a high conjugation extent with improved roll-off efficiency
Authors: Jayabharathi Jayaraman , Thanikachalam Venugopal , Thilagavathy Shanmugam , Anudeebhana Jagathratchagan
Published: July 2022

The BOLEDs/green- Ir(ppy)3)/red-Ir(MDQ)2(acac) device with TPA-2SPPITPA show maximum EQE of 6.13/27.23/19.01%, CE of 5.92/81.87/28.76 cd/A, PE of 5.15/75.23/24.73 lm/W and CIE of (0.15, 0.07)/ (0.33, 0.60)/(0.65,0.33).
Vertically-aligned quasi-2D cesium lead halide perovskite solar cells
Authors: Liu Xuanling , Tai Meiqian , Gu Jingkun , Wu Ziyi , Zhong Han , Wang Xuanyu , Wang Zhiping , Lin Hong
Published: July 2022

Vertically-aligned PEA2Cs3Pb4I13films with improved film coverage and phase purity are achieved by controlling the crystallization kinetics with DMSO and MACl.
Photodetection and scintillation characterizations of novel lead-bismuth double perovskite halides
Authors: Maddalena Francesco , Witkowski Marcin E. , Makowski Michal , Bachiri Abdellah , Arramel  , Yang Ting , Mahyuddin Muhammad Haris , Baravaglio Matilde , Boutchich Mohamed , Drozdowski Winicjusz , Dujardin Christophe , Birowosuto Muhammad Danang , Dang Cuong
Published: July 2022

Double perovskite materials with large effective atomic numbers and high mass densities generate short absorption length for radiation detection. Bromide and iodide variants were characterized for their scintillation and photodetection properties.
Pseudo Janus based on rhombohedral homobilayer transition metal dichalcogenides
Authors: Lin Changqing , Xiang Hui , Xiong Heqi , Ahmad Sohail , Xu Bo , Zhao Puqin , Cheng Yingchun
Published: July 2022

Out-of-plane mirror symmetry breaking has enabled pseudo Janus structures as a platform to explore the coupling between electric polarization, piezoelectricity, spin–orbit coupling, and Rashba splitting in a two-dimensional (2D) system.
Dibenzo heterocyclic-terminated spiro-type hole transporting materials for perovskite solar cells
Authors: Liang Yongpeng , Chen Jianlin , Zhang Xianfu , Han Mingyuan , Ghadari Rahim , Wu Nan , Wang Ying , Zhou Ying , Liu Xuepeng , Dai Songyuan
Published: July 2022

spiro-DBF exhibits higher hole mobility, better morphology and stronger hole extraction ability than spiro-OMeTAD, resulting in a higher PCE.
The molecular basis of cereal grain proteostasis
Authors: Cao Hui , Duncan Owen , Millar A. Harvey
Published: July 2022

Storage proteins deposited in the endosperm of cereal grains are both a nitrogen reserve for seed germination and seedling growth and a primary protein source for human nutrition. Detailed surveys of the patterns of storage protein accumulation in cereal grains during grain development have been undertaken, but an in-depth understanding of the molecular mechanisms that regulate these patterns is still lacking. Accumulation of storage proteins in cereal grains involves a series of subcellular compartments, a set of energy-dependent events that compete with other cellular processes, and a balance of protein synthesis and protein degradation rates at different times during the developmental process. In this review, we focus on the importance of rates in cereal grain storage protein accumulation during grain development and outline the potential implications and applications of this information to accelerate modern agriculture breeding programmes and optimize energy use efficiency in proteostasis.
Identifying Language Disorder in Bilingual Children Using Automatic Speech Recognition
Authors: Albudoor Nahar , Peña Elizabeth D.
Published: July 2022

Purpose:

The differential diagnosis of developmental language disorder (DLD) in bilingual children represents a unique challenge due to their distributed language exposure and knowledge. The current evidence indicates that dual-language testing yields the most accurate classification of DLD among bilinguals, but there are limited personnel and resources to support this practice. The purpose of this study was therefore to determine the feasibility of dual-language automatic speech recognition (ASR) for identifying DLD in bilingual children.

Method:

Eighty-four Spanish–English bilingual second graders with (
n
= 25) and without (
n
= 59) confirmed diagnoses of DLD completed the Bilingual English-Spanish Assessment–Middle Extension Morphosyntax in both languages. Their responses on a subset of items were scored manually by human examiners and programmatically by a researcher-developed ASR application employing a commercial speech-to-text algorithm.

Results:

Results demonstrated moderate overall item-by-item scoring agreement (
k
= .54) and similar classification accuracy values (human = 92%, ASR = 88%) between the two methods using the best-language score. Classification accuracy of the ASR method increased to 94% of cases correctly classified when test items with poorer discrimination in the ASR condition were eliminated.

Conclusion:

This study provides preliminary support for the technical feasibility of ASR as a bilingual expressive language assessment tool.

Supplemental Material:

https://doi.org/10.23641/asha.20249994
DMA‐Net: Dual multi‐instance attention network for X‐ray image classification
Authors: Liu Shuoyan , Yang Enze , Liu Yuxin , Zhao Shitao
Published: July 2022

Security inspection has been playing a critical role in protecting public space from safety threats. As object detection is a fundamental and mature research filed, it still suffers from numerous challenges such as scale, viewpoint and intra‐class variance of X‐ray images. The main reasons are, mis‐modeling of actual security inspection as well as insufficient effective X‐ray samples. To this end, the X‐ray inspection task is reconsidered by predicting the dangerous attributes without boxes and categories, a Dual Multi‐instance Attention network (DMA‐Net) is proposed in this paper to mine the key‐instance from both patch and proposal branch. In patch‐level multi‐instance attention pooling, Recursive Attention Pyramid (RAP) and Spatial‐Channel Attention (SCA) are proposed to effectively learn discriminative representation from hierarchical features. Meanwhile, the proposal‐level multi‐instance attention pooling selectively emphasizes interdependent of crucial regions. The features of dual pooling layers are fused to predict dangerous attributes of X‐ray inspection images directly. Further, this paper contributes a large‐scale and high‐quality X‐ray image dataset from railway stations, named Railway Station X‐ray (RSXray). Enormous experiments on RSXray, GDXray and SIXray demonstrate that the proposed DMA‐Net achieves surprising performance with dual multi instance learning diagrams and attention mechanism. The superiority of the employed framework for applications in real world scenarios are also verified.
Quasars as high-redshift standard candles
Authors: Sacchi A. , Risaliti G. , Signorini M. , Lusso E. , Nardini E. , Bargiacchi G. , Bisogni S. , Civano F. , Elvis M. , Fabbiano G. , Gilli R. , Trefoloni B. , Vignali C.
Published: July 2022

The non-linear relation between the X-ray and ultraviolet (UV) luminosity in quasars has been used to derive quasar distances and to build a Hubble diagram at redshifts up to z ∼ 7. This cosmological application is based on the assumption of independence of the relation on redshift and luminosity. We want to test the reliability of this hypothesis by studying the spectroscopic properties of high-redshift quasars in the X-ray and UV bands. We performed a one-by-one analysis of a sample of 130 quasars at z > 2.5 with high-quality X-ray and UV spectroscopic observations. We found that not only does the X-ray to UV correlation still hold at these redshifts, but its intrinsic dispersion is as low as 0.12 dex (previous works reached 0.20–0.22 dex). For a sample of quasars at z ∼ 3 with particularly high-quality observations, the dispersion further drops to 0.09 dex, a value entirely accountable for by intrinsic variability and source geometry effects. The composite spectra of these quasars, in both the X-rays and the UV, do not show any difference with respect to the average spectra of quasars at lower redshifts. The absence of any spectral difference between high- and low-z quasars and the tightness of the X-ray to UV relation suggests that no evolutionary effects are present in the relation. Therefore, it can be safely employed to derive quasar distances. Under this assumption, we obtain a measurement for the luminosity distance at z ∼ 3 with 15% uncertainty, and in a 4σ tension with the concordance model.
Effects of Resistance Priming Exercise on Within-day Jumping
Performance and its Relationship with Strength Level
Authors: González-García Jaime , Latella Christopher , Aguilar-Navarro Millán , Romero-Moraleda Blanca
Published: July 2022

This study aimed to identify the effects of same-day resistance priming exercise
on countermovement jump parameters and subjective readiness, and to identify
whether baseline strength level influenced these outcomes. Fourteen participants
performed two separate conditions (Priming [2 sets high-load parallel squats
with a 20% velocity loss cut-off] and Control) in a randomized,
counterbalanced crossover design. Countermovement jump was assessed at pre, post
and 6 h while readiness was assessed at pre and at 6 h only. All
countermovement jump force-time metrics were similar between conditions
(p>0.05), but different individual responses were noted
6 h after priming. Jump height was increased for 4/14, decreased
for another 4/14, and maintained for 6/14 participants at
6 h. Higher perceived physical performance capability
(p<0.001) and activation balance (p=0.005) were
observed after priming only. Positive relationships were observed between
strength and the percentage change in jump height (r=0.47–0.50;
p=0.033–0.042), concentric peak velocity
(r=0.48–0.51; p=0.030–0.041) and
impulse (r=0.47; p=0.030–0.045) at
post and 6 h after priming exercise. These findings suggest that
velocity-based high-load low-volume priming exercise has potential to positively
impact jump performance and subjective readiness later that day in certain
individuals. Participant absolute strength level may influence this response but
should be confirmed in subsequent studies.
Arcade Sutures to Minimize Ear Displacement in Rhytidectomy
Authors: Abraham Manoj T. , Klimczak Jaclyn A. , Hart Hannah , Hu Shirley , Abraham-Aggarwal Minali
Published: July 2022

Ear deformities after rhytidectomy are not uncommon and have a significant impact on cosmetic success. We postulate the use of horizontal mattress suspension sutures in the anterior face anchored to the deep temporalis fascia (DTF) during rhytidectomy allows for a vertical lift while minimizing the risk to the frontal branch of the facial nerve and decreasing forward rotation of the ear. To compare auricular displacement during rhytidectomy using an arcade of horizontal mattress suspension sutures anchored to the DTF instead of the preauricular pre-parotid fascia, and evaluate outcomes with this modification at 1 year. This was a proof of concept prospective cohort study of 20 patients (40 sides) undergoing rhytidectomy by a single plastic surgeon (level of evidence 4). Intraoperative measurements were taken to determine the amount of auricular displacement with suspension sutures placed in the preauricular fascia compared with the DTF. To confirm longevity, we compared ear position preoperatively and at 1 year after rhytidectomy with our technique. There was significantly less auricular displacement when superficial musculoaponeurotic system (SMAS) suspension sutures were placed in the DTF 0.75 ± 0.69 mm compared with the preauricular fascia 9.71 ± 2.57 mm (p < 0.00001). With our technique at an average follow-up of 370.3 days, there was no significant change in auricular rotation compared with preoperative photos (p = 0.125).Our simple rhytidectomy modification allows for vertical resuspension of the SMAS in the anterior face in a safe manner while minimizing displacement of the auricle.
Inhibiting Interleukin-6/Signal Transducers and Activators of Transduction-3/Hypoxia-Inducible Factor-1α Signaling Pathway Suppressed the Growth of Infantile Hemangioma
Authors: Maimaiti Aziguli , Aierken Yeerfan , Zhou Ling , He Jun , Abudureyimu Abudusaimi , Li Shui-Xue
Published: July 2022

Objective This study aims to evaluate the expression of interleukin 6 (IL-6) in patients with infantile hemangioma (IH) and investigate the role of the IL-6/signal transducers and activators of transduction-3 (STAT3)/hypoxia-inducible factor-1α (HIF-1α) pathways in the progression of IH.

Methods Serum samples were obtained from the patients with IH and normal infants to measure IL-6 expression. Hemangioma-derived stem cells (HemSCs) were transfected with small interfering RNA (siRNA) targeting IL-6, HIF-1α, or STAT3. Then, cell viability and wound healing assays were conducted. After that, the HemSC tumor mouse model was established. The in vivo anticancer effect of the IL-6 inhibitor was investigated.

Results The patients with IH had much higher IL-6 levels compared with the healthy controls (p = 0.005). HemSCs transfected with IL-6 siRNA had significantly lower viability and migration rates than normal HemSCs. HemSCs transfected with STAT3 siRNA or HIF-1α siRNA had similar tendencies. On tumor-bearing mice, the IL-6 inhibitor treatment significantly delayed tumor growth. Compared with the control group, caspase-3 was significantly increased in the IL-6 inhibitor group (p < 0.05), whereas Ki-67 was decreased in the IL-6 inhibitor group (p < 0.05). In the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, the IL-6 inhibitor group had much higher apoptosis rates than the controls (p < 0.05).

Conclusion Our findings indicate that inhibiting the IL-6/STAT3/HIF-1α signaling pathways could suppress IH growth.
Differential equation for partition functions and a duality pseudo-forest
Authors: Vanchurin Vitaly
Published: July 2022

We consider finite quantum systems defined by a mixed set of commutation and anti-commutation relations between components of the Hamiltonian operator. These relations are represented by an anti-commutativity graph that contains necessary and sufficient information for computing the full quantum partition function. We derive a second-order differential equation for an extended partition function z[β, β′, J] that describes a transformation from a “parent” partition function z[0, β′, J] (or anti-commutativity graph) to a “child” partition function z[β, 0, J] (or anti-commutativity graph). The procedure can be iterated, and then one forms a pseudo-forest of duality transformations between quantum systems, i.e., a directed graph in which every vertex (or quantum system) has at most one incoming edge (from its parent system). The pseudo-forest has a single tree connected to a constant partition function, many pseudo-trees connected to self-dual systems, and all other pseudo-trees connected to closed cycles of transformations between mutually dual systems. We also show how the differential equation for the extended partition function can be used to study disordered systems.
Game-theoretical approach for opinion dynamics on social networks
Authors: Li Zhifang , Chen Xiaojie , Yang Han-Xin , Szolnoki Attila
Published: July 2022

Opinion dynamics on social networks have received considerable attentions in recent years. Nevertheless, just a few works have theoretically analyzed the condition in which a certain opinion can spread in the whole structured population. In this article, we propose an evolutionary game approach for a binary opinion model to explore the conditions for an opinion’s spreading. Inspired by real-life observations, we assume that an agent’s choice to select an opinion is not random but is based on a score rooted from both public knowledge and the interactions with neighbors. By means of coalescing random walks, we obtain a condition in which opinion A can be favored to spread on social networks in the weak selection limit. We find that the successfully spreading condition of opinion A is closely related to the basic scores of binary opinions, the feedback scores on opinion interactions, and the structural parameters including the edge weights, the weighted degrees of vertices, and the average degree of the network. In particular, when individuals adjust their opinions based solely on the public information, the vitality of opinion A depends exclusively on the difference of basic scores of A and B. When there are no negative (positive) feedback interactions between connected individuals, we find that the success of opinion A depends on the ratio of the obtained positive (negative) feedback scores of competing opinions. To complete our study, we perform computer simulations on fully connected, small-world, and scale-free networks, respectively, which support and confirm our theoretical findings.
Frequency-segmented power amplification using multi-band radio frequency amplifiers to produce a high-voltage pulse
Authors: Togawa Kazuaki , Maesaka Hirokazu , Kobana Reichiro , Tanaka Hitoshi
Published: July 2022

A method of frequency-segmented power amplification using multiband radio frequency (RF) amplifiers was proposed to generate stable and arbitrary high-voltage pulses. The concept behind this method is that an arbitrary pulse with a specified duration and sharp edges can be reconstructed using only several frequencies, and most of the power is concentrated on the fundamental frequency. The high-voltage pulse can, therefore, be obtained by amplifying each segmented frequency and then combining it with the RF power combiners. To correct the frequency-dependent group delays and gain of the amplifier circuit and to perform fine-tuning of the pulse structure, a seed pulse is divided into several lines that have bandpass filters, variable delay lines, variable power attenuators, and main RF amplifiers. A prototype pulse amplifier was designed and fabricated based on this method to generate rectangular pulses for the electron beam chopper of an x-ray free-electron laser injector. Flat and stable pulses with a 2 ns width of 0.2 kV height, peak-to-peak flat top of 0.8%, and route-mean-squared peak jitter of less than 0.2% were successively generated in both single- and multi-bunch structures. In the future, this type of pulse generator will play an important role in accelerators that require complicated and precise beam handling at high repetition rates of kHz or MHz.
Negative Schottky barrier height and surface inhomogeneity in n-silicon M–I–S structures
Authors: Harisha C. P. , Liao M.-H. , Kei C.-C. , Joshi S.
Published: July 2022

The alleviation effect on the Schottky barrier height (SBH) (ΦB) using ultrathin titanium dioxide and hafnium dioxide dielectrics in a single layer and a bilayer stack was demonstrated. ΦB in the Pt/n-Si contact was reduced from 0.53 to −0.058, 0.3, and −0.12 eV using 3 nm TiO2, 1 nm HfO2, and high-k/high-k bilayer insertion, respectively. A maximum of 122% reduction in ΦB was obtained using bilayer dielectric insertion, which is the highest ever reduction reported so far in a Schottky diode. This was achieved by effectively passivating the semiconductor surface states by HF cleaning followed by inserting an ultrathin film produced from the novel Atomic Layer Deposition (ALD) technique. The Gaussian distribution (GD) of barrier heights all over the interface has been investigated for both Metal–Semiconductor (M–S) and Metal–Insulator–Semiconductor (M–I–S) contacts. The nonlinear behavior in a conventional Richardson plot was observed with lower values of the Richardson constant (A*). We have reported the surface inhomogeneity in both M–S and M–I–S contacts through temperature dependency of diode characteristics. The standard deviation (σ) as evidence for the Gaussian distribution of barrier heights was determined using the ln(Is/T2) vs q/2kT plot. The results were validated by a modified Richardson plot where the values of A* obtained were found to be in close agreement with the known values. As the ALD technique is known for conformity and uniformity of thin films, the dielectric insertion has proved effective in mitigating the SBH. However, the inhomogeneity in both M–S and M–I–S points to the role of dipole formation at the interface.
The chemical Langevin equation for biochemical systems in dynamic environments
Authors: Ham Lucy , Coomer Megan A. , Stumpf Michael P. H.
Published: July 2022

Modeling and simulation of complex biochemical reaction networks form cornerstones of modern biophysics. Many of the approaches developed so far capture temporal fluctuations due to the inherent stochasticity of the biophysical processes, referred to as intrinsic noise. Stochastic fluctuations, however, predominantly stem from the interplay of the network with many other—and mostly unknown—fluctuating processes, as well as with various random signals arising from the extracellular world; these sources contribute extrinsic noise. Here, we provide a computational simulation method to probe the stochastic dynamics of biochemical systems subject to both intrinsic and extrinsic noise. We develop an extrinsic chemical Langevin equation (CLE)—a physically motivated extension of the CLE—to model intrinsically noisy reaction networks embedded in a stochastically fluctuating environment. The extrinsic CLE is a continuous approximation to the chemical master equation (CME) with time-varying propensities. In our approach, noise is incorporated at the level of the CME, and it can account for the full dynamics of the exogenous noise process, irrespective of timescales and their mismatches. We show that our method accurately captures the first two moments of the stationary probability density when compared with exact stochastic simulation methods while reducing the computational runtime by several orders of magnitude. Our approach provides a method that is practical, computationally efficient, and physically accurate to study systems that are simultaneously subject to a variety of noise sources.
Melnikov-type method for a class of hybrid piecewise-smooth systems with impulsive effect and noise excitation: Homoclinic orbits
Authors: Li Yuxi , Wei Zhouchao , Zhang Wei , Yi Ming
Published: July 2022

The Melnikov method is extended to a class of hybrid piecewise-smooth systems with impulsive effect and noise excitation when an unperturbed system is a piecewise Hamiltonian system with a homoclinic orbit. The homoclinic orbit continuously crosses the first switching manifold and transversally jumps across the second switching manifold by the impulsive effect. The trajectory of the corresponding perturbed system crosses the first switching manifold by applying the reset map describing the impact rule instantaneously. Then, the random Melnikov process of such systems is derived and the criteria for the onset of chaos with or without noise excitation are established. In addition, the complicated dynamics of concrete piecewise-smooth systems with or without noise excitation under the reset maps, impulsive effect, and non-autonomous periodic and damping perturbations are investigated by this extended method and numerical simulations.
Multiscale modeling of semimetal contact to two-dimensional transition metal dichalcogenide semiconductor
Authors: Wu Tong , Guo Jing
Published: July 2022

A multiscale simulation approach is developed to simulate the contact transport properties between semimetal and a monolayer two-dimensional transition metal dichalcogenide (TMDC) semiconductor. The results elucidate the mechanisms for low contact resistance between semimetal and TMDC semiconductor contacts from a quantum transport perspective. The simulation results compare favorably with recent experiments. Furthermore, the results show that the contact resistance of a bismuth-MoS2 contact can be further reduced by engineering the dielectric environment and doping the TMDC material to <100 Ω·μm. The quantum transport simulation indicates the possibility to achieve an ultrashort contact transfer length of ∼1 nm, which can allow aggressive scaling of the contact size.
Liquid-cooled modular gas cell system for high-order harmonic generation using high average power laser systems
Authors: Filus Zoltán , Ye Peng , Csizmadia Tamás , Grósz Tímea , Gulyás Oldal Lénárd , De Marco Massimo , Füle Miklós , Kahaly Subhendu , Varjú Katalin , Major Balázs
Published: July 2022

We present the design and implementation of a new, modular gas target suitable for high-order harmonic generation using high average power lasers. To ensure thermal stability in this high heat load environment, we implement an appropriate liquid cooling system. The system can be used in multiple-cell configurations, allowing us to control the cell length and aperture size. The cell design was optimized with heat and flow simulations for thermal characteristics, vacuum compatibility, and generation medium properties. Finally, the cell system was experimentally validated by conducting high-order harmonic generation measurements using the 100 kHz high average power HR-1 laser system at the Extreme Light Infrastructure Attosecond Light Pulse Source (ELI ALPS) facility. Such a robust, versatile, and stackable gas cell arrangement can easily be adapted to different experimental geometries in both table-top laboratory systems and user-oriented facilities, such as ELI ALPS.
Molecular dynamics of linear molecules in strong magnetic fields
Authors: Monzel Laurenz , Pausch Ansgar , Peters Laurens D. M. , Tellgren Erik I. , Helgaker Trygve , Klopper Wim
Published: July 2022

Molecular rotations and vibrations have been extensively studied by chemists for decades, both experimentally using spectroscopic methods and theoretically with the help of quantum chemistry. However, the theoretical investigation of molecular rotations and vibrations in strong magnetic fields requires computationally more demanding tools. As such, proper calculations of rotational and vibrational spectra were not feasible up until very recently. In this work, we present rotational and vibrational spectra for two small linear molecules, H2 and LiH, in strong magnetic fields. By treating the nuclei as classical particles, trajectories for rotations and vibrations are simulated from ab initio molecular dynamics. Born–Oppenheimer potential energy surfaces are calculated at the Hartree–Fock and MP2 levels of theory using London atomic orbitals to ensure gauge origin invariance. For the calculation of nuclear trajectories, a highly efficient Tajima propagator is introduced, incorporating the Berry curvature tensor accounting for the screening of nuclear charges.
Phononic crystal-induced standing Lamb wave for the translation of subwavelength microparticles
Authors: Huang Laixin , Li Fei , Cai Feiyan , Meng Long , Zhou Wei , Kong Deqing , Zheng Hairong
Published: July 2022

Phononic crystals (PCs) can modulate an incident acoustic wave to provide subwavelength microparticles with stable and flexible manipulation. However, fixed artificial structures of the PCs usually result in a steady acoustic field profile, thus limiting the dynamic manipulation of microparticles. This study proposes the construction of a phononic crystal plate (PCP) using a pair of periodic oppositely arranged gratings on a plate. Under the PCP's resonance frequency, a pair of nonleaky A0 mode traveling Lamb waves that intrinsically exist in a thin plate were excited and propagated. The pair of waves formed a highly localized standing Lamb wave field between the pair of periodic gratings. By adjusting the phase of the incident acoustic wave, the positions of pressure nodes of the PCP-induced standing Lamb wave were changed in a quantitatively tunable manner. Thus, polystyrene microparticles trapped and aligned at the pressure nodes via the acoustic radiation force could be moved to achieve the translation motion with a resolution of 2.2 μm, approximately 1/160 wavelength in water. The proposed methodology will lead to the fabrication of a disposable and easily operated tool for dynamically manipulating microparticles in subwavelength regions by engineering acoustic fields using acoustic metamaterials in microfluidic devices for cell sorting and drug delivery.
Strain-induced irreversible change of the conductive network in a rubber/carbon-black composite revealed by polarization-resolved terahertz dielectric spectroscopy
Authors: Mizuta Keisuke , Okano Makoto , Morimoto Takahiro , Ata Seisuke , Watanabe Shinichi
Published: July 2022

The dielectric response during the deformation of a rubber composite filled with carbon black (CB) was studied by polarization-resolved terahertz spectroscopy, because the characterization of such responses can be used to reveal strain-induced irreversible changes in the electrical properties of a CB-filled rubber. During the first stretching-and-relaxation cycle, two characteristic behaviors were observed: strain-induced anisotropy and an irreversible reduction of the dielectric constants in the measured frequency range. To understand the origin of this result, we tried to reproduce the strain dependence of the dielectric function with a modified effective medium theory that accounts for the orientational distribution of the CB aggregates. From the dependence of the fitting parameters on the deformation condition, it was found that the reduction of the dielectric constants in the terahertz frequency range is mainly caused by the breakdown of the CB-based conductive network due to a dissociation of CB agglomerates. This finding indicates that polarization-resolved terahertz spectroscopy is a promising technique for the assessment of changes in the internal structure of CB fillers on the nanometer scale.
Excellent temperature stability of energy storage performance by weak dipolar interaction strategy
Authors: Ji Xiaoli , Li Feng , Long Mingsheng , Wang Chunchang , Shan Lei
Published: July 2022

High-performance dielectric materials are widely used in energy storage applications, and temperature stability at extreme conditions is rarely considered yet. In this work, the Bi0.5Na0.5TiO3–Sr0.7Bi0.2□0.1TiO3–xNaNbO3 (x = 0, 0.05, and 0.15) system is designed with a room-temperature ergodic relaxor character to explore energy storage evolution with temperature. The addition of NaNbO3 increases tetragonal (P4bm) phase content and relaxor disorders and leads to a downshift of transition temperature, as verified by Rietveld refinement, dielectric analysis, and in situ Raman spectra. Superior temperature stability of recoverable energy storage density (WRec, change rate: δ ≤ 14%) and efficiency (η = 0.79–0.98) is found in x = 0.15 composition in a wide temperature range of 243–373 K, in contrast to a significant variation for x = 0 (δ ≤ 85%, η = 0.08–0.88) and 0.05 (δ ≤ 36%, η = 0.60–0.96) compositions. The dielectric relaxation speed is faster in x = 0.15, as characterized by on–off-electric field dielectric curves. This work demonstrates that the weak-dipolar-interaction system retards dipolar coalescence under cryogenic temperature and, thus, maintains high energy storage efficiency, which predicts their suitability in energy storage applications at an extreme condition.
Efficient computational methods for rovibrational transition rates in molecular collisions
Authors: Selim Taha , van der Avoird Ad , Groenenboom Gerrit C.
Published: July 2022

Astrophysical modeling of processes in environments that are not in local thermal equilibrium requires the knowledge of state-to-state rate coefficients of rovibrational transitions in molecular collisions. These rate coefficients can be obtained from coupled-channel (CC) quantum scattering calculations, which are very demanding, however. Here, we present various approximate but more efficient methods based on the coupled-states approximation (CSA), which neglects the off-diagonal Coriolis coupling in the scattering Hamiltonian in body-fixed coordinates. In particular, we investigated a method called NNCC (nearest-neighbor Coriolis coupling) [Yang et al., J. Chem. Phys. 148, 084101 (2018)] that includes Coriolis coupling to first order. The NNCC method is more demanding than the common CSA method but still much more efficient than full CC calculations, and it is substantially more accurate than CSA. All of this is illustrated by showing state-to-state cross sections and rate coefficients of rovibrational transitions induced in CO2 by collisions with He atoms. It is also shown that a further reduction of CPU time, practically without loss of accuracy, can be obtained by combining the NNCC method with the multi-channel distorted-wave Born approximation that we applied in full CC calculations in a previous paper.
IL-24 intrinsically regulates Th17 cell pathogenicity in mice
Authors: Sie Christopher , Kant Ravi , Peter Christian , Muschaweckh Andreas , Pfaller Monika , Nirschl Lucy , Moreno Helena Domínguez , Chadimová Tereza , Lepennetier Gildas , Kuhlmann Tanja , Öllinger Rupert , Engleitner Thomas , Rad Roland , Korn Thomas
Published: July 2022

In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.
Dendritic spine morphology regulates calcium-dependent synaptic weight change
Authors: Bell Miriam K. , Holst Maven V. , Lee Christopher T. , Rangamani Padmini
Published: July 2022

Dendritic spines act as biochemical computational units and must adapt their responses according to their activation history. Calcium influx acts as the first signaling step during postsynaptic activation and is a determinant of synaptic weight change. Dendritic spines also come in a variety of sizes and shapes. To probe the relationship between calcium dynamics and spine morphology, we used a stochastic reaction-diffusion model of calcium dynamics in idealized and realistic geometries. We show that despite the stochastic nature of the various calcium channels, receptors, and pumps, spine size and shape can modulate calcium dynamics and subsequently synaptic weight updates in a deterministic manner. Through a series of exhaustive simulations and analyses, we found that the calcium dynamics and synaptic weight change depend on the volume-to-surface area of the spine. The relationships between calcium dynamics and spine morphology identified in idealized geometries also hold in realistic geometries, suggesting that there are geometrically determined deterministic relationships that may modulate synaptic weight change.
Highly dispersed platinum deposited on nitrogen-doped vertical graphene array for efficient electrochemical hydrogen evolution
Authors: Yang Hongzhou , Yang Zhaojun , Han Zhaojun , Chu Dewei , Chen Chaoqiu , Xie Xiaoying , Shang Lu , Zhang Tierui
Published: July 2022

The electrochemical hydrogen evolution is a key technology for future renewable energy conversion and storage. Platinum is the most efficient catalyst for hydrogen evolution reaction (HER), but its mass activity should be boosted further. Herein, we deposited platinum on nitrogen-doped vertical graphene through an atomic layer deposition method. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy confirmed that the platinum was highly dispersed on the array substrate. On account of the array structure and high dispersion of platinum, the synthesized catalyst exhibited high HER performance with a low overpotential of 42 mV at 10 mA cm−2 and a low Tafel slope of 52.2 mV dec−1. Significantly, the synthesized catalyst exhibited a high mass activity of 4.45 A mg−1
Pt, which was ∼13 times higher than that of commercial Pt/C.
Effect of rare earth on microstructure and properties of niobiumizing layer on GCr15 steel for pin shaft
Authors: Meng Lingyao , Shang Jian , Zhang Mengjiu , Xie Aijun
Published: July 2022

The powder pack cementation was used for niobiumizing treatment of GCr15 pin steel, and the effects of different rare earth types and contents on microstructure and properties of niobiumizing layer were investigated. Optical microscope, x-ray diffractometer, scanning electron microscope, electrochemical workstation and ball-disk friction wear machine were used to observe the structure and evaluate the properties of the niobiumizing layer. And the kinetics and mechanism of niobiumizing layer with rare earths was explored. The results show that a dense and continuous niobiumizing layer formed under different rare earth types and contents condition. The layer is 3 μm-15 μm in average thickness, 1800 HV0.2-2500 HV0.2 in average microhardness and is composed of NbCx compound and α-Fe. Comprehensive comparison, La2O3 can significantly improve the wear and corrosion resistance of the niobiumizing layer. The self-corrosion potential of niobiumizing layer is −0.5759 V, the corrosion current density is 5.2365 × 10−7 A cm−2, and the average friction coefficient is 0.385 when La2O3 is added at 2%.
An evaluation of the loading direction sensitivity of 3D woven composite with novel web-shaped Z-binder architecture
Authors: Panwar Arpit , Neelakrishnan S
Published: July 2022

3D orthogonal (ORT) through-thickness woven composites have excellent out-of-plane properties but exhibit inferior in-plane properties and are loading sensitive. This study proposes a novel web-shaped orientation of z-binder architecture in 3D orthogonal through-thickness model with in-plane uniform elastic moduli to address this drawback. On-axis tensile, Off-axis tensile and In-plane Shear tests were performed on the four macroscale models (ORTon, WEBon, ORToff, WEBoff). The ORT model, validated by data from the literature, was used as a reference for the proposed WEB model. The overall fibre volume fraction of the WEBon, and WEBoff models were 7.07% and 8.67% lower than the ORTon, and ORToff models. In the on-axis tensile test, the Ex and Ey were lower by 16.89% and 2.66% for WEBon model, but in the off-axis tensile test, they were higher by 13.75% and 13.77% for WEBoff models. The Gxy was 10.96% lower for WEBon model. The difference between the Ex and Ey under on-axis loading conditions was 14.81% for ORT model, whereas 0.22% for WEB model. Thus, the proposed WEB shaped z-binder architecture model outperforms the ORT model under the off-axis and is comparable in transverse loading conditions. It also possesses loading direction insensitivity, unlike the ORT model.
Effect of the microstructure on the corrosion behavior of dissimilar friction stir-welded 304 austenitic stainless steel and Q235 low-carbon steel joints
Authors: Wang Hongduo , Zhang Chengwen , Zhou Zhiyong , Zhang Yunzi , Wang Kuaishe , Wang Wen , Han Peng , Lu Yongxin , Li Xiao , Liu Yanming , Zhang Xiaoyong , Zhou Yong , Xu Xueli
Published: July 2022

To investigate the effect of the microstructure on the corrosion behavior of the dissimilar friction stir welded (FSW) joint between 304 stainless steel (SS304) and Q235 low-carbon steel, the microstructure of the joint in this work was characterized by optical microscopy, scanning electron microscopy (SEM), and electron backscatter diffraction. The corrosion behavior in different zones of the joint was evaluated by the electrochemical tests, and the corresponding corrosion morphologies were illustrated via SEM and laser confocal scanning microscopy. According to the results, plenty of low-angle grain boundaries (LAGBs) and a low proportion of twin boundaries (TBs) deteriorated the corrosion resistance on the SS304 side of the joint. The corrosion products of the SS304 side mainly included γ-Fe2O3, FeCrO4, and Cr2O3, while those of the Q235 steel side were α-Fe2O3 and α-FeOOH. The corrosion mechanism in the stir zone (SZ) was galvanic corrosion between proeutectoid ferrite and pearlite on the Q235 steel side, during which the austenite remained uncorroded, whereas the proeutectoid ferrite, pearlite, and bainite were severely corroded. The above results indicated that the uniform distribution of mixed structures and a small area proportion of austenite (cathode) would improve the corrosion resistance in the SZ.
Mesoporous silica dispersed Co3O4-CuO nanocomposite and its catalytic reduction of 4-nitrophenol
Authors: Ma Yunlei , Zhu Yunjing , Yue Haopeng , Jiang Guojian , Wu Dandan
Published: July 2022

Herein, a catalyst Co3O4-CuO nanocomposite uniformly dispersed on mesoporous silica nanospheres (MSN) has been successfully synthesized through hydrothermal method. The synthesis method is simple and convenient, the prepared Co3O4-CuO nanocomposites have high dispersibility, and the support SiO2 maintains the structure of mesoporous nanospheres. What’s more, the porous structure enables the obtained composite to have a high specific surface area (128.89 m2 g−1), which is easier to be contacted by catalytic substrates. The catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) was investigated. The results show that the nanocomposite catalyst Co3O4-CuO@MSN present good catalytic performance, which can completely convert 4-NP to 4-AP in 200 s and the reaction rate constant k is up to 0.149 s−1. More important, the possible degradation mechanism was also proposed in the paper.
Does the metric matter? Climate change impacts of light-duty vehicle electrification in the US
Authors: Milovanoff Alexandre , MacLean Heather L , Abdul-Manan Amir F N , Posen I Daniel
Published: July 2022

Vehicle electrification is one of the most promising climate change mitigation strategies for light-duty vehicles (LDVs). But vehicle electrification shifts the greenhouse gas (GHG) emission profiles of conventional LDVs with emissions moving upstream from vehicle use to electricity generation and vehicle production. Electric vehicle (EV) deployment needs to be examined with life cycle assessment (LCA), both at vehicle and fleet levels. Climate change assessments of EVs are usually conducted using global warming potential (GWP), a normalized metric that aggregates GHG emissions. GWP suffers from some limitations as it ignores the emission timing over the product life cycle. In this study, we examine climate change impacts of four vehicle technologies (conventional, hybrid, plug-in hybrid, and battery electric vehicles) in the US at vehicle and fleet levels using four climate change metrics (GWP, dynamic global warming impact, radiative forcing impact and global temperature change impact). One of our key findings is that while the choices of the metric, the analytical time period, and some other key parameters, such as methane leakage rate, may have substantial influences on the results, partial and full electrification remain effective solutions to reduce climate change impacts of the US LDVs. However, the transient effects that exist between GHG emissions, radiative forcing, and global temperature changes imply that climate change impact reductions of vehicle electrification take time to materialize and are overestimated with GWP. It is therefore critical to evaluate large-scale implications of climate change mitigation strategies with multiple metrics to fully capture and assess the expected benefits. We nonetheless found that GWP is a robust metric for climate change mitigation targets of vehicle electrification and remains a good choice for most analysis.
Approximating viscosity solutions of the Euler system
Authors: Feireisl Eduard , Lukáčová-Medvid’ová Mária , Schneider Simon , She Bangwei
Published: July 2022

Applying the concept of S-convergence, based on averaging in the spirit of Strong Law of Large Numbers, the vanishing viscosity solutions of the Euler system are studied. We show how to efficiently compute a viscosity solution of the Euler system as the S-limit of numerical solutions obtained by the viscosity finite volume method. Theoretical results are illustrated by numerical simulations of the Kelvin–Helmholtz instability problem.