bluuebunny/crossref_metadata_2025 huggingface dataset:
Light-shift mitigation in a microcell-based atomic clock with symmetric auto-balanced Ramsey spectroscopy
Authors: Abdel Hafiz M. , Carlé C. , Passilly N. , Danet J. M. , Calosso C. E. , Boudot R.
Published: February 2022

The mid-term fractional frequency stability of miniaturized atomic clocks can be limited by light-shift effects. In this Letter, we demonstrate the implementation of a symmetric auto-balanced Ramsey (SABR) interrogation sequence in a microcell-based atomic clock based on coherent population trapping. Using this advanced protocol, the sensitivity of the clock frequency to laser power, microwave power, and laser frequency variations is reduced, at least by one order of magnitude, in comparison with continuous-wave or Ramsey interrogation schemes. Light-shift mitigation obtained with the SABR sequence benefits greatly to the clock Allan deviation for integration times between 102 and 105 s. These results demonstrate that such interrogation techniques are of interest to enhance the timekeeping performance of chip-scale atomic clocks.
Observation and modeling of bound-free transitions to the X1Σ+ and a3Σ+ states of KCs
Authors: Krumins V. , Kruzins A. , Tamanis M. , Ferber R. , Meshkov V. V. , Pazyuk E. A. , Stolyarov A. V. , Pashov A.
Published: February 2022

The oscillation continuum in laser-induced fluorescence spectra of bound-free c3Σ+ → a3Σ+ and (4)1Σ+ → X1Σ+ transitions of the KCs molecule was recorded by a Fourier-transform spectrometer and modeled under the adiabatic approximation. The required interatomic potentials for ground a3Σ+ and X1Σ+ states were reconstructed in an analytical Chebyshev-polynomial-expansion form in the framework of the regularization direct-potential-fit procedure based on the simultaneous consideration of experimental line positions from Ferber et al. [Phys. Rev. A 80, 062501 (2009)] and the present ab initio calculation of short-range repulsive potential data. It was proved that the repulsive part over the dissociation limit of the derived a3Σ+ potential reproduces the experiment better than the potentials reported in the literature. It is also shown that all empirical and semi-empirical potentials available for the X1Σ+ state reproduce the bound-free (4)1Σ+ → X1Σ+ spectrum with equal quality in the range of observations.
Ultrafast vibrational dynamics of aqueous acetate and terephthalate
Authors: Korotkevich Alexander A. , Bakker Huib J.
Published: February 2022

We study the vibrational population relaxation and mutual interaction of the symmetric stretch (νs) and antisymmetric stretch (νas) vibrations of the carboxylate anion groups of acetate and terephthalate ions in aqueous solution by femtosecond two-dimensional infrared spectroscopy. By selectively exciting and probing the νs and νas vibrations, we find that the interaction of the two vibrations involves both the anharmonic coupling of the vibrations and energy exchange between the excited states of the vibrations. We find that both the vibrational population relaxation and the energy exchange are faster for terephthalate than for acetate.
Thermally activated intra-chain charge transport in high charge-carrier mobility copolymers
Authors: Dilmurat Rishat , Prodhan Suryoday , Wang Linjun , Beljonne David
Published: February 2022

Disordered or even seemingly amorphous, donor–acceptor type, conjugated copolymers with high charge-carrier mobility have emerged as a new class of functional materials, where transport along the conjugated backbone is key. Here, we report on non-adiabatic molecular dynamics simulations of charge-carrier transport along chains of poly (indacenodithiophene-co-benzothiadiazole), within a model Hamiltonian parameterized against first-principles calculations. We predict thermally activated charge transport associated with a slightly twisted ground-state conformation, on par with experimental results. Our results also demonstrate that the energy mismatch between the hole on the donor vs the acceptor units of the copolymer drives localization of the charge carriers and limits the intra-chain charge-carrier mobility. We predict that room-temperature mobility values in excess of 10 cm2 V−1 s−1 can be achieved through proper chemical tuning of the component monomer units.
Automated search for optimal surface phases (ASOPs) in grand canonical ensemble powered by machine learning
Authors: Chen Dongxiao , Shang Cheng , Liu Zhi-Pan
Published: February 2022

The surface of a material often undergoes dramatic structure evolution under a chemical environment, which, in turn, helps determine the different properties of the material. Here, we develop a general-purpose method for the automated search of optimal surface phases (ASOPs) in the grand canonical ensemble, which is facilitated by the stochastic surface walking (SSW) global optimization based on global neural network (G-NN) potential. The ASOP simulation starts by enumerating a series of composition grids, then utilizes SSW-NN to explore the configuration and composition spaces of surface phases, and relies on the Monte Carlo scheme to focus on energetically favorable compositions. The method is applied to silver surface oxide formation under the catalytic ethene epoxidation conditions. The known phases of surface oxides on Ag(111) are reproduced, and new phases on Ag(100) are revealed, which exhibit novel structure features that could be critical for understanding ethene epoxidation. Our results demonstrate that the ASOP method provides an automated and efficient way for probing complex surface structures that are beneficial for designing new functional materials under working conditions.
Development and validation of microsatellite markers for kikuyu grass using next generation sequencing technology
Authors: Arango Juliana , López Albeiro , Márquez Edna , Echeverri Julián
Published: February 2022

Context The kikuyu grass (Cenchrus clandestinus) is native to Africa and is one of the most widely used grasses for forage feeding in dairy regions around the world. Aims To obtain the first set of microsatellite markers for the population genetics study of kikuyu grass, using nextgeneration sequencing technology (Illumina MiSeq). Methods Sixty loci were evaluated, in which a subset of 12 loci were selected to be used for a complete population analysis in 108 samples of kikuyu, and were grouped in to three zones of Colombia. The three approaches with which the genetic structure was evaluated. Key results Obtained same tendency of grouping reflects a low genetic differentiation, specifically evidencing differences between the northern zone of Antioquia and the zones that comprise the other territories of Colombia. Conclusions These reads of microsatellite loci help to complement the information on the genetic structure of the populations of the kikuyu, and will be useful for the characterisation and evaluation of the diversity of germplasm in other parts of the world. Implications The set of microsatellite markers developed has a species-specific reproducibility and could be used for studies in other Cenchrus individuals and particularly in future investigations with Kikuyu grass. Likewise, this research presents findings in a broad context and relates them to other pasture species.
Non-invasive monitoring and reintroduction biology of the brush-tailed rock-wallaby (
Authors: Kleemann S. , Sandow D. , Stevens M. , Schultz D. J. , Taggart D. A. , Croxford A.
Published: February 2022

Thirty-nine endangered brush-tailed rock-wallabies (Petrogale penicillata) were reintroduced to Grampians National Park, western Victoria, between 2008 and 2012. Subsequent high mortality, low breeding, and no recruitment were linked to fox predation and physical disturbance during monitoring. From 2014 to 2017, the colony was left undisturbed and monitored only by remote camera. Five adult animals were identified across this period (1 ♂ and 3 ♀s – all tagged; and one untagged female), and an average of 0.7 pouch young were birthed per tagged female per year. In 2019, camera-monitoring and non-invasive genetic monitoring (faecal) were used to identify colony members, genetic diversity, and breeding. Camera monitoring in 2019 identified the same five individuals, whereas genetic monitoring using 12 microsatellites identified eight individuals (two male and six female genotypes). Genetic diversity within the colony was moderate (expected heterozygosity (He) = 0.655, observed heterozygosity (Ho) = 0.854). Leaving the colony undisturbed after 2013 correlated with improved adult survival, increased breeding, and successful recruitment of young to the population. Recommendations for the Grampians colony include continuation of regular camera- and scat monitoring to improve our understanding of the reintroduction biology of P. penicillata and other marsupials in open, unfenced landscapes.
Recently constructed hydropower dams were associated with reduced economic production, population, and greenness in nearby areas
Authors: Fan Peilei , Cho Myung Sik , Lin Zihan , Ouyang Zutao , Qi Jiaguo , Chen Jiquan , Moran Emilio F.
Published: February 2022

Significance

This research provides a global-scale evaluation of the impact of dam construction by using a variety of global spatial databases. In particular, it provides insight into the impacts on economy, population, and greenness of 631 recently built hydropower dams by region and dam size. We discovered that 631 recently built hydropower dams were associated with reduced local economy, population, and greenness in areas within 50 km of the dam sites, particularly in the Global South. This is contrary to claims that dams improve the livelihoods of people as well as ecosystem services. The research highlights that policy interventions are needed to address impacts on populations and urban land near small and medium dams.
The influence of iodine on the Antarctic stratospheric ozone hole
Authors: Cuevas Carlos A. , Fernandez Rafael P. , Kinnison Douglas E. , Li Qinyi , Lamarque Jean-François , Trabelsi Tarek , Francisco Joseph S. , Solomon Susan , Saiz-Lopez Alfonso
Published: February 2022

Significance

The role of chlorine and bromine in Antarctic stratospheric ozone depletion is well known. However, the contribution of iodine to the ozone hole chemistry has not been assessed, mainly due to the negligible amounts of iodine previously reported to enter the stratosphere. New measurements demonstrate that the injection of iodine to the lower stratosphere is higher than previously assumed. Based on these observations, our modeling work shows that iodine chemistry can enhance spring ozone loss at the lower part of the Antarctic ozone hole, and even dominate the halogen-mediated ozone loss during summer. Iodine can also alter, by several days, the timing of the seasonal formation and closure of the ozone hole.
Differential interferon-α subtype induced immune signatures are associated with suppression of SARS-CoV-2 infection
Authors: Schuhenn Jonas , Meister Toni Luise , Todt Daniel , Bracht Thilo , Schork Karin , Billaud Jean-Noel , Elsner Carina , Heinen Natalie , Karakoese Zehra , Haid Sibylle , Kumar Sriram , Brunotte Linda , Eisenacher Martin , Di Yunyun , Lew Jocelyne , Falzarano Darryl , Chen Jieliang , Yuan Zhenghong , Pietschmann Thomas , Wiegmann Bettina , Uebner Hendrik , Taube Christian , Le-Trilling Vu Thuy Khanh , Trilling Mirko , Krawczyk Adalbert , Ludwig Stephan , Sitek Barbara , Steinmann Eike , Dittmer Ulf , Lavender Kerry J. , Sutter Kathrin , Pfaender Stephanie
Published: February 2022

Significance

Type I interferons (IFN-I) exhibit various biological effects during viral infections, and they have been successfully used for clinical treatment of viral diseases. Humans express 12 IFNα subtypes, which strongly differ in their antiviral responses against different viruses. Here we analyzed the antiviral activity of all human IFNα subtypes against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to identify the underlying immune signatures and explore their therapeutic potential. Our data provide a systemic pattern of antiviral host effector responses mediated by high antiviral IFN-I, which could help to identify key cellular effectors targeted in novel therapeutic approaches against SARS-CoV-2 infection.
A complete description of thermodynamic stabilities of molecular crystals
Authors: Kapil Venkat , Engel Edgar A.
Published: February 2022

Significance

Predicting stable polymorphs of molecular crystals remains one of the grand challenges of computational science. Current methods invoke approximations to electronic structure and statistical mechanics and thus fail to consistently reproduce the delicate balance of physical effects determining thermodynamic stability. We compute the rigorous ab initio Gibbs free energies for competing polymorphs of paradigmatic compounds, using machine learning to mitigate costs. The accurate description of electronic structure and full treatment of quantum statistical mechanics allow us to predict the experimentally observed phase behavior. This constitutes a key step toward the first-principles design of functional materials for applications from photovoltaics to pharmaceuticals.
Comparing the reliability and predictive power of child, teacher, and guardian reports of noncognitive skills
Authors: Feng Shuaizhang , Han Yujie , Heckman James J. , Kautz Tim
Published: February 2022

Significance

Recent evidence has shown that noncognitive or socioemotional skills (e.g., persistence and self-control) are predictive of success in life and can be shaped through interventions. Accordingly, policy makers and researchers have increasingly measured children’s noncognitive skills, typically relying on surveys in which children rate their own skills or adults rate the skills of children. Such ratings are often collected from multiple respondent types. This study demonstrates that, compared with child and guardian reports of noncognitive skills, teacher reports are more predictive of children’s cognitive and behavioral outcomes in school. Child and guardian reports add minimal predictive power beyond teacher reports. These findings suggest that policy makers and researchers should prioritize teacher reports above those of children and guardians.
Autoreactive antibodies control blood glucose by regulating insulin homeostasis
Authors: Amendt Timm , Allies Gabriele , Nicolò Antonella , El Ayoubi Omar , Young Marc , Röszer Tamás , Setz Corinna S. , Warnatz Klaus , Jumaa Hassan
Published: February 2022

Significance

The random nature of antibody repertoire generation includes the potential of producing autoantibodies recognizing self-structures. It is believed that establishing immunological tolerance and prevention of autoimmune diseases require the removal of antibody specificities recognizing self. Using insulin as a common and physiologically important autoantigen, we show that anti-insulin antibodies associated with autoimmune diabetes can readily be detected in mice and humans and are involved in the physiological regulation of blood glucose levels. Importantly, human high-affinity, anti-insulin IgM antibodies protect insulin from autoimmune degradation by anti-insulin IgG antibodies. Thus, in contrast to the proposed negative selection, self-recognition and the production of highly autoreactive IgM antibodies are important for tolerance induction.
Metabolomic selection for enhanced fruit flavor
Authors: Colantonio Vincent , Ferrão Luis Felipe V. , Tieman Denise M. , Bliznyuk Nikolay , Sims Charles , Klee Harry J. , Munoz Patricio , Resende Marcio F. R.
Published: February 2022

Significance

Consumers often regard heirloom fruit varieties grown in the garden as more flavorful than commercial varieties purchased at the grocery store. While plant breeders have historically focused on improving producer-orientated traits such as yield, consumer-oriented traits such as flavor have regularly been neglected. This is, in part, due to the difficulty associated with measuring the sensory perceptions of flavor. Here, we combine fruit chemical and consumer sensory panel information to train machine learning models that can predict how flavorful a fruit will be from its chemistry. By increasing the throughput of flavor evaluations, these models will help plant breeders to integrate flavor earlier in the breeding pipeline and aid in the design of varieties with exceptional flavor profiles.
Middle Eastern and North African Americans may not be perceived, nor perceive themselves, to be White
Authors: Maghbouleh Neda , Schachter Ariela , Flores René D.
Published: February 2022

Significance

The US government’s classification of Middle Eastern and North African (MENA) Americans as White means there is no direct way to numerically count members of this group in official statistics. Therefore, any potential disparities and inequalities faced by MENA Americans remain hidden. Nevertheless, we find that MENA Americans may not be perceived, nor perceive themselves, to be White. These findings underscore the minoritized status of MENA Americans and support the inclusion of a new MENA identity category in the US Census. This would allow researchers to examine the social, economic, and health status of this growing population and empower community advocates to ameliorate existing inequalities.
A minimal cage of a diamond twin with chirality
Authors: Fukunaga Toshiya M. , Kato Takahide , Ikemoto Koki , Isobe Hiroyuki
Published: February 2022

Significance

Diamonds enchant people with their beauty, which has also been defined by mathematics. The existence of strong isotropy with maximal symmetry in carbon networks has been mathematically disclosed, which has led to a proposal of a diamond twin. Unlike tetrahedral vertices of the diamond, trigonal vertices of the diamond twin achieve strong isotropy, notably, with chirality. In the diamond twin, 14 trigonal vertices are connected by 15 edges to form a minimal cage. Although the diamond-twin network indeed had a four-decade history in theory, it remained imaginary in reality due to its inevitable instability of the minimal cage. In this paper, the carbonaceous minimal cage of the diamond twin has been synthesized, which reveals unique structural features including helical chirality.
Structural mechanism of allosteric activation of TRPML1 by PI(3,5)P2and rapamycin
Authors: Gan Ninghai , Han Yan , Zeng Weizhong , Wang Yan , Xue Jing , Jiang Youxing
Published: February 2022

Significance

Rapamycin is a specific inhibitor of mammalian target of rapamycin (mTOR). Rapamycin can also activate transient receptor potential mucolipin 1 (TRPML1), a phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2]–gated lysosomal cation channel whose loss-of-function mutations directly cause mucolipidosis type IV disease. We determined the high-resolution cryoelectron microscopy structures of TRPML1 in various ligand-bound states, including the open TRPML1 in complex with PI(3,5)P2and a rapamycin analog at 2.1 Å. These structures reveal how rapamycin and PI(3,5)P2bind at two distinct sites and allosterically activate the channel. Considering the high potency of TRPML1 activation by rapamycin and PI(3,5)P2, it is conceivable that some pharmacological effects from the therapeutic use of rapamycin may come from the TRPML1-dependent mechanism rather than mTOR inhibition.
Plant immunity: Rice XA21-mediated resistance to bacterial infection
Authors: Ercoli María Florencia , Luu Dee Dee , Rim Ellen Youngsoo , Shigenaga Alexandra , Teixeira de Araujo Artur , Chern Mawsheng , Jain Rashmi , Ruan Randy , Joe Anna , Stewart Valley , Ronald Pamela
Published: February 2022

Significance

The mechanisms plants employ to resist infection were unknown until just a few decades ago. We now understand that plants utilize diverse classes of immune receptors to recognize and respond to pathogenic microbes and pests. This paper describes the development of the plant immunity field, from early studies on the genetics of disease resistance to our increasing knowledge of how plant receptors interact with their microbial ligands, with an emphasis on the rice immune receptor XA21 and its bacterial ligand.
Multi-Type Solitons in Spin-Orbit Coupled Spin-1 Bose–Einstein Condensates
Authors: He Jun-Tao , Fang Ping-Ping , Lin Ji
Published: February 2022

Recently, research of solitons in Bose–Einstein condensates has become a popular topic. Here, we mainly study exact analytical solutions of Gross–Pitaevskii equations describing spin-orbit coupled spin-1 Bose–Einstein condensates. To begin with, we show the analytical relation between different types of one-dimensional spin-orbit coupling and Zeeman effect. In addition, we find a transformation that can simplify the three-component Gross–Pitaevskii equations with spin-orbit coupling into the nonlinear Schrödinger equation. The abundant stripe phase and dynamic characteristics of the system are investigated.
Evidence for a High-Pressure Isostructural Transition in Nitrogen
Authors: Fan Chunmei , Liu Shan , Liu Jingyi , Wu Binbin , Tang Qiqi , Tao Yu , Pu Meifang , Zhang Feng , Li Jianfu , Wang Xiaoli , He Duanwei , Zhou Chunyin , Lei Li
Published: February 2022

We observed an isostructural phase transition in the solid nitrogen λ-N2 at approximately 50 GPa accompanied by anomalies in lattice parameters, atomic volume and Raman vibron modes. The anomalies are ascribed to a slight reorientation of the nitrogen molecules, which does not seem to affect the monoclinic symmetry (space group P21/c). Our ab initio calculations further confirm the phenomena, and suggest an optimized structure for the λ-N2 phase. In addition, a new high-pressure amorphous phase of η′-N2 was also discovered by a detailed investigation of the pressure-temperature phase diagram of nitrogen with the aim of probing the phase stability of λ-N2. Our result may provide helpful information about the crystallographic nature of dissociation transitions in diatomic molecular crystals (H2, O2, N2, etc).
Electrochemical Role of Transition Metals in Sn–Fe Alloy Revealed by Operando Magnetometry
Authors: Zhang Le-Qing , Xia Qing-Tao , Li Zhao-Hui , Han Yuan-Yuan , Xu Xi-Xiang , Zhao Xin-Long , Wang Xia , Pan Yuan-Yuan , Li Hong-Sen , Li Qiang
Published: February 2022

As promising materials, alloy-type anode materials have been intensively investigated in both academia and industry. To release huge volume expansion during alloying/dealloying process, they are usually doped with transition metals. However, the electrochemical role of transition metals has not been fully understood. Here, pure Sn3Fe films were deposited by sputtering, and the electrochemical mechanism was systematically investigated by operando magnetometry. We confirmed that Fe particles liberated by Li insertion recombine partially with Sn during the delithiation, while the stepwise increase in magnetization with the cycles demonstrates growth of Fe nanoparticles. In addition, we also found an unconventional increase of magnetization in the charging process, which can be attributed to the space charge storage at the interface of Fe/Li
x
Sn. These critical findings pave the way for the mechanism understanding and development of high-performance Sn based alloy electrode materials.
Effects of actuation mode on plasma-induced spanwise flow oscillations
Authors: Hehner Marc T , Gatti Davide , Kotsonis Marios , Kriegseis Jochen
Published: February 2022

Two different plasma actuation strategies for producing near-wall flow oscillations, namely the burst-modulation and beat-frequency mode, are characterized with planar particle image velocimetry in quiescent air. Both concepts are anticipated to work as non-mechanical surrogates of oscillating walls aimed at turbulent flow drag reduction, with the added benefit of no moving parts, as the fluid is purely manipulated by plasma-generated body forces. The current work builds upon established flow-control and proof-of-concept demonstrators, as such, delivering an in-depth characterization of cause and impact of the plasma-induced flow oscillations. Various operational parameter combinations (oscillation frequency, duty cycle and input body force) are investigated. A universal performance diagram that is valid for plasma-based oscillations, independent of the actuation concept is derived. Results show that selected combinations of body force application methods suffice to reproduce oscillating wall dynamics from experimental data. Accordingly, the outcomes of this work can be exploited to create enhanced actuation models for numerical simulations of plasma-induced flow oscillations, by considering the body force as a function of the oscillation phase. Furthermore, as an advantage over physically displaced walls, the exerted body force appears not to be hampered by resonances and therefore remains constant independent of the oscillation frequency. Hence, the effects of individual parameter changes on the plasma actuator performance and fluid response as well as strategies to avoid undesired effects can be determined.
Polarised superlocalization in magnetic nanoparticle hyperthermia
Authors: Iszály Zsofia , Gresits Iván , Márián István Gábor , Thuróczy György , Sági Oliver , Márkus Bence Gábor , Simon Ferenc , Nandori Istvan
Published: February 2022

Magnetic hyperthermia is an adjuvant therapy for cancer where injected magnetic nanoparticles are used to transfer energy from the time-dependent applied magnetic ﬁeld into the surrounding medium. Its main importance is to be able to increase the temperature of the human body locally. This localization can be further increased by using a combination of static and alternating external magnetic ﬁelds. For example, if the static ﬁeld is inhomogeneous and the alternating ﬁeld is oscillating then the energy transfer and consequently, the heat generation is non-vanishing only where the gradient ﬁeld is zero which results in superlocalization. Our goal here is to study theoretically and experimentally whether the perpendicular or parallel combination of static and oscillating ﬁelds produce a better superlocalization. A considerable polarisation eﬀect in superlocalization for small frequencies and large ﬁeld strengths which are of great importance in practice is found.
H2O2 adsorption and dissociation on various CeO2 (111) surface models: a first-principles study
Authors: Brugnoli Luca , Urata Shingo , Pedone Alfonso
Published: February 2022

Periodic density functional theory (DFT) calculations using the hybrid PBE0 functional and atom-centered Gaussian functions as basis sets were carried out to investigate the absorption and the first steps involved in the decomposition of hydrogen peroxide (H2O2) on three different models of the ceria (111) surface. One of the models is a clean surface, and the others are defective and partially hydroxylated ceria surfaces. On the clean surface, we found that the minimum energy path of hydrogen peroxide decomposition involves a three-step process, i.e., adsorption, deprotonation, and formation of the peroxide anion, stabilized through its interaction with the surface at a Ce (IV) site, with activation barriers of less than about 0.5 eV. The subsequent formation of superoxide anions and molecular oxygen species is attributed to electron transfer from the reactants to the Ce (IV) ions underneath. On the defective surface, H2O2 dissociation is an energetically downhill reaction thermodynamically driven by the healing of the O vacancies, after the reduction and decomposition of H2O2 into oxygen and water. On the hydroxylated surface, H2O2 is first adsorbed by forming a favorable H-bond and then undergoes heterolytic dissociation, forming two hydroxyl groups at two vicinal Ce sites.
N, P, O-codoped biochar from phytoremediation residues: a promising cathode material for Li–S batteries
Authors: Zhong Mei’e , Sun Jingchun , Shu Xiaoqing , Guan Jindiao , Tong Gongsong , Ding Hao , Chen Liying , Zhou Nan , Shuai Yi
Published: February 2022

Environment and energy are two key issues in today’s society. In terms of environmental protection, the treatment of phytoremediation residues has become a key problem to be solved urgently, while for energy storage, it tends to utilize low-cost and high specific energy storage materials (i.e. porous carbon). In this study, the phytoremediation residues is applied to the storage materials with low-cost and high specific capacity. Firstly, the phosphorous acid assisted pyrolysis of oilseed rape stems from phytoremediation is effective in the removal of Zn, Cu, Cd and Cr from the derived biochar. Moreover, the derived biochar from phytoremediation residues shows abundant porous structure and polar groups (–O/–P/–N), and it can deliver 650 mAh g−1 with 3.0 mg cm−2
sulfur, and keeps 80% capacity after 200 cycles when employing it as a sulfur host for lithium–sulfur (Li–S) batteries. Hence, phosphorous acid assisted pyrolysis and application in Li–S battery is a promising approach for the disposal of phytoremediation residues, which is contributed to the environmental protection as well as energy storage.
Surface amorphous coating for an economical and high-stability current collector for rechargeable aluminum-ion batteries
Authors: Guo Hanlin , Zhou Rui , Li Xu , Li Zhenhu , Liu Shuangyi
Published: February 2022

Rechargeable aluminum-ion batteries (AIBs) are regarded as the next-generation energy storage devices due to their low flammability, low cost and high power density as well as abundant aluminum (Al) reserves. However, these popular ionic liquid electrolytes contain highly corrosive acid, which always corrodes the most used positive current collector, thus hindering the commercialization of AIBs. This study proposes an efficient and economical method of coating amorphous Ni3S2 compound on a nickel metal current collector (Ni-S/Ni). The conductivity and the onset oxidation potential of amorphous Ni3S2 coating can be up to 2.3 × 106 S m−1 and 2.7 V respectively. A Ni-S/Ni current collector can provide excellent cycling stability with no electrochemical corrosion in the AIBs. The AIBs fabricated using a Ni-S/Ni current collector exhibits a specific capacity of 65 mAh/g at 1 A g−1, high coulombic efficiency of 99% and cyclability of at least 2000 cycles. Moreover, the total cost of the Ni-S/Ni current collector can be limited to less than 3.3 USD/m2. The comprehensive performances of these AIBs are better than most reported results so far, which indicates that this method can advance the commercialization of AIBs.
Long-range medical image registration through generalized mutual information (GMI): towards a fully automatic volumetric alignment
Authors: Vianna Vinicius Pavanelli , Murta Luiz Otavio
Published: February 2022

Objective. Mutual information (MI) is consolidated as a robust similarity metric often used for medical image registration. Although MI provides a robust registration, it usually fails when the transform needed to register an image is too large due to MI local minima traps. This paper proposes and evaluates Generalized MI (GMI), using Tsallis entropy, to improve affine registration. Approach. We assessed the GMI metric output space using separable affine transforms to seek a better gradient space. The range used was 150 mm for translations, 360° for rotations, [0.5, 2] for scaling, and [−1, 1] for skewness. The data were evaluated using 3D visualization of gradient and contour curves. A simulated gradient descent algorithm was also used to calculate the registration capability. The improvements detected were then tested through Monte Carlo simulation of actual registrations with brain T1 and T2 MRI from the HCP dataset. Main results. Results show significantly prolonged registration ranges, without local minima in the metric space, with a registration capability of 100% for translations, 88.2% for rotations, 100% for scaling and 100% for skewness. Tsallis entropy obtained 99.75% success in the Monte Carlo simulation of 2000 translation registrations with 1113 double randomized subjects T1 and T2 brain MRI against 56.5% success for the Shannon entropy. Significance. Tsallis entropy can improve brain MRI MI affine registration with long-range translation registration, lower-cost interpolation, and faster registrations through a better gradient space.
Quantum corrected polymer black hole thermodynamics: mass relations and logarithmic entropy correction
Authors: Mele Fabio M. , Münch Johannes , Pateloudis Stratos
Published: February 2022

In this paper, we continue the analysis of the effective model of quantum Schwarz­schild black holes recently proposed by some of the authors in [1,2]. In the resulting quantum-corrected spacetime the central singularity is resolved by a black-to-white hole bounce, quantum effects become relevant at a unique mass-independent curvature scale, while they become negligible in the low curvature region near the horizon and classical Schwarzschild geometry is approached asymptotically. This is the case independently of the relation between the black and white hole masses, which are thus freely specifiable independent observables. A natural question then arises about the phenomenological implications of the resulting non-singular effective spacetime and whether some specific relation between the masses can be singled out from a phenomenological perspective. Here we focus on the thermodynamic properties of the effective polymer black hole and analyze the corresponding quantum corrections as functions of black and white hole masses. The study of the relevant thermodynamic quantities such as temperature, specific heat, and horizon entropy reveals that the effective spacetime generically admits an extremal minimal-sized configuration of quantum-gravitational nature characterized by vanishing temperature and entropy. For large masses, the classically expected results are recovered at leading order and quantum corrections are negligible, thus providing us with a further consistency check of the model. The explicit form of the corrections depends on the specific relationship among the masses. In particular, a first-order logarithmic correction to the black hole entropy is obtained for a quadratic mass relation. The latter corresponds to the case of proper finite-length effects which turn out to be compatible with a minimal length generalized uncertainty principle associated with an extremal Planck-sized black hole.
Representation of the coherent state for a beam splitter operator and its applications
Authors: Zhan Mingxia , Jia Fang , Huang Jiali , Zhang Huan , Hu Liyun
Published: February 2022

A beam splitter operator is a very important linear device in the field of quantum optics and quantum information. It can not only be used to prepare complete representations of quantum mechanics, entangled state representation, but it can also be used to simulate the dissipative environment of quantum systems. In this paper, by combining the transform relation of the beam splitter operator and the technique of integration within the product of the operator, we present the coherent state representation of the operator and the corresponding normal ordering form. Based on this, we consider the applications of the coherent state representation of the beam splitter operator, such as deriving some operator identities and entangled state representation preparation with continuous-discrete variables. Furthermore, we extend our investigation to two single and two-mode cascaded beam splitter operators, giving the corresponding coherent state representation and its normal ordering form. In addition, the application of a beam splitter to prepare entangled states in quantum teleportation is further investigated, and the fidelity is discussed. The above results provide good theoretical value in the fields of quantum optics and quantum information.
Kinetic theory of Jeans’ gravitational instability in millicharged dark matter system
Authors: Chen Hui , Yang Wei-Heng , Xiong Yu-Zhen , Liu San-Qiu
Published: February 2022

The possibility of baryons cooled by a millicharged dark matter (mDM) via mDM-baryons scattering has recently been proposed to explain the observation discrepancy from the experiment to detect the global epoch of reionization signature (EDGES). In this sense, we analyze the Jeans instability of self-gravitational systems in the background of mDM under kinetic regime that the collisionless Boltzmann equation and Poisson equation have been combined to obtain the modified dispersion relation. It is shown that the effect of mDM is significant on the dynamics of gravitational collapse, i.e., the presence of mDM makes the self-gravitational systems more difficult to collapse relatively.
Quantum algorithm for neighborhood preserving embedding
Authors: Pan Shi-Jie , Wan Lin-Chun , Liu Hai-Ling , Wu Yu-Sen , Qin Su-Juan , Wen Qiao-Yan , Gao Fei
Published: February 2022

Neighborhood preserving embedding (NPE) is an important linear dimensionality reduction technique that aims at preserving the local manifold structure. NPE contains three steps, i.e., finding the nearest neighbors of each data point, constructing the weight matrix, and obtaining the transformation matrix. Liang et al. proposed a variational quantum algorithm (VQA) for NPE [Phys. Rev. A
101 032323 (2020)]. The algorithm consists of three quantum sub-algorithms, corresponding to the three steps of NPE, and was expected to have an exponential speedup on the dimensionality n. However, the algorithm has two disadvantages: (i) It is not known how to efficiently obtain the input of the third sub-algorithm from the output of the second one. (ii) Its complexity cannot be rigorously analyzed because the third sub-algorithm in it is a VQA. In this paper, we propose a complete quantum algorithm for NPE, in which we redesign the three sub-algorithms and give a rigorous complexity analysis. It is shown that our algorithm can achieve a polynomial speedup on the number of data points m and an exponential speedup on the dimensionality n under certain conditions over the classical NPE algorithm, and achieve a significant speedup compared to Liang et al.’s algorithm even without considering the complexity of the VQA.
Mg-doped layered oxide cathode for Na-ion batteries
Authors: Ding Yuejun , Ding Feixiang , Rong Xiaohui , Lu Yaxiang , Hu Yong-Sheng
Published: February 2022

Na-ion batteries (NIBs) are regarding as the optimum complement for Li-ion batteries along with the rapid development of stationary energy storage systems. In order to meet the commercial demands of cathodes for NIBs, O3-type Cu containing layered oxide Na0.90Cu0.22Fe0.30Mn0.48O2 with good comprehensive performance and low-cost element components is very promising for the practical use. However, only part of the Cu3+/Cu2+ redox couple participated in the redox reaction, thus impairing the specific capacity of the cathode materials. Herein, Mg2+-doped O3-Na0.90Mg0.08Cu0.22Fe0.30Mn0.40O2 layered oxide without Mn3+ was synthesized successfully, which exhibited improved reversible specific capacity of 118 mAh/g in the voltage range of 2.4–4.0 V at 0.2 C, corresponding to the intercalation/deintercalation of 0.47 Na+ (0.1 more than that of Na0.90Cu0.22Fe0.30Mn0.48O2). This work demonstrates an important strategy to obtain advanced layered oxide cathodes for NIBs.
Strain-mediated magnetoelectric control of tunneling magnetoresistance in magnetic tunneling junction/ferroelectric hybrid structures
Authors: Huang Wenyu , Wang Cangmin , Liu Yichao , Wang Shaoting , Ge Weifeng , Qiu Huaili , Yang Yuanjun , Zhang Ting , Zhang Hui , Gao Chen
Published: February 2022

Because of the wide selectivity of ferromagnetic and ferroelectric (FE) components, electric-field (E-field) control of magnetism via strain mediation can be easily realized through composite multiferroic heterostructures. Here, an MgO-based magnetic tunnel junction (MTJ) is chosen rationally as the ferromagnetic constitution and a high-activity (001)-Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (PMN-0.3PT) single crystal is selected as the FE component to create a multiferroic MTJ/FE hybrid structure. The shape of tunneling magnetoresistance (TMR) versus in situ E-fields imprints the butterfly loop of the piezo-strain of the FE without magnetic-field bias. The E-field-controlled change in the TMR ratio is up to –0.27% without magnetic-field bias. Moreover, when a typical magnetic field (∼ ±10 Oe) is applied along the minor axis of the MTJ, the butterfly loop is changed significantly by the E-fields relative to that without magnetic-field bias. This suggests that the E-field-controlled junction resistance is spin-dependent and correlated with magnetization switching in the free layer of the MTJ. In addition, based on such a multiferroic heterostructure, a strain-gauge factor up to approximately 40 is achieved, which decreases further with a sign change from positive to negative with increasing magnetic fields. This multiferroic hybrid structure is a promising avenue to control TMR through E-fields in low-power-consumption spintronic and straintronic devices at room temperature.
Electromagnetic wave absorption properties of Ba(CoTi)
x
Fe12–2x
O19@BiFeO3 in hundreds of megahertz band
Authors: Xu Zhi-Biao , Qi Zhao-Hui , Wang Guo-Wu , Liu Chang , Cui Jing-Hao , Li Wen-Liang , Wang Tao
Published: February 2022

The high-performance electromagnetic (EM) wave absorption material Ba(CoTi)
x
Fe12–2x
O19@BiFeO3 was prepared by solid-state reaction, and its EM wave absorption properties were deeply studied. The results revealed that Ba(CoTi)
x
Fe12–2x
O19@BiFeO3 could obtain excellent absorption properties in hundreds of megahertz by adjusting the Co2+–Ti4+ content. The best comprehensive property was obtained for x = 1.2, where the optimal reflection loss (RL) value reaches –30.42 dB at about 600 MHz with thickness of 3.5 mm, and the corresponding effective absorption band covers the frequency range of 437 MHz–1 GHz. Moreover, the EM wave absorption mechanism was studied based on the simulation methods. The simulated results showed that the excellent EM wave absorption properties of Ba(CoTi)
x
Fe12–2x
O19@BiFeO3 mainly originated from the internal loss caused by natural resonance, and the interface cancelation further improved the absorption properties and resulted in RL peaks.
THz wave generation by repeated and continuous frequency conversions from pump wave to high-order Stokes waves
Authors: Li Zhongyang , Yan Qianze , Liu Pengxiang , Jiao Binzhe , Zhang Gege , Chen Zhiliang , Bing Pibin , Yuan Sheng , Zhong Kai , Yao Jianquan
Published: February 2022

We propose a novel scheme for THz wave generation by repeated and continuous frequency conversions from pump wave to high-order Stokes waves (HSWs). The repeated frequency conversions are accomplished by oscillations of Stoke waves in resonant cavity (RC) where low-order Stokes waves (LSWs) are converted to high-order Stokes waves again and again. The continuous frequency conversions are accomplished by optimized cascaded difference frequency generation (OCDFG) where the poling periods of the optical crystal are aperiodic leading to the frequency conversions from low-order Stokes waves to high-order Stokes waves uninterruptedly and unidirectionally. Combined with the repeated and continuous frequency conversions, the optical-to-THz energy conversion efficiency (OTECE) exceeds 26% at 300 K and 43% at 100 K with pump intensities of 300 MW/cm2.
Resolving challenges of monitoring PV systems: a case study for three 1.5 kW generators in Lima, Peru
Authors: Berastain A E , Conde L A , Angulo J , Carhuavilca A M , García M , Sevillano-Bendezú M A , Montes-Romero J , De la Casa J , Chirinos L , Töfflinger J A
Published: February 2022

This paper addresses challenges from monitoring three grid-connected PV systems with different module technologies in Lima, Peru, following the International Electrotechnical Commission (IEC) standards. Missing and erroneous data due to sensor malfunction or partial shadowing can negatively impact the measured data quality. We developed a program to automatically detect erroneous measurements, enhance the data quality, and calculate PV performance parameters following the IEC-61724 standard to resolve these challenges. The program includes mathematical methods to replace faulty or missing measurements. Finally, we present the impact of the algorithms for erroneous data detection, deletion, and correction on performance calculations.
Global solar radiation time series forecasting using different architectures of the multilayer perceptron model
Authors: Peñalva J J , Lozano D A , Murillo J C , Ortega F M
Published: February 2022

In this work, the multilayer perceptron model was used to forecast the time series of global solar radiation for a near future about a week. Different architectures of this model were built through varying its different hyperparameters such as optimizers, activation functions, number of neurons and neuron dropout in which their performance was evaluated using error metrics. It was found that the architectures (60, SGD, Sigmoid), (10, Adam, Relu) and (60, SGD, Sigmoid) presented an R2 around 0.877, 0.873 and 0.872, respectively. The architecture with neuron dropout (150, SGD, Sigmoid, 0.2) presented a higher performance among all the architectures evaluated and its R2 value was 0.884. Architectures with higher performance are used to predict future values of solar radiation.
Application of machine learning and deep learning in mask detection
Authors: Wang Zihan , Xu Xuefei
Published: February 2022

The world witnessed the outbreak of coronavirus disease (COVID-19) at the end of 2019. Even in the 2021, this disease still caused difficulties and inconvenience to millions of people. COVID-19 pandemic has made it a necessity for almost everyone to wear a facial mask as a protective measure. There are several methods to detect masked face, including deep learning and machine learning, which constitutes an integral part on people’s normal life. In order to find a faster and more convenient way to detect whether people wearing masks, this paper compared advantages and disadvantages between deep learning and machine learning based on existing literature, and proposed the most suitable method for detecting masks under different practical conditions. Therefore, we can monitor whether people wear masks correctly and give them timely guidance.
Research on path planning algorithm of intelligent inspection robot
Authors: Wang Yuechao , Mai Ying , Wen Weijian
Published: February 2022

With the development of intelligent inspection robot technology, inspection robots are widely used in substations to complete the inspection work of substations and move toward intelligent inspection. At present, substations begin to reduce the number of inspection personnel, reduce labor costs, and improve inspection efficiency and ensure the safe operation of electrical equipment in substations by using inspection robots to conduct intelligent inspection of substation equipment. The algorithm is used to realize the path planning of the inspection robot and model the substation environment.
RGBD salient object detection based on depth feature enhancement
Authors: Shi Yue , Yu Wanjun , Guan Qianxun
Published: February 2022

The depth map contains spatial location information, which has been proven to be beneficial for RGBD salient object detection. However, the quality of the depth map will directly affect the accuracy of RGBD saliency detection. In order to solve the problem of different quality of depth maps, a detection model based on depth enhancement is designed to enhance the available depth information and filter low-quality depth maps. By comparing four evaluation indicators with five advanced models, the experimental results show that the model in this paper is advanced.