bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors associated with difficulty in crossing the culprit lesion of acute myocardial infarction
Authors: Ishibashi Shun , Sakakura Kenichi , Asada Satoshi , Taniguchi Yousuke , Jinnouchi Hiroyuki , Tsukui Takunori , Yamamoto Kei , Seguchi Masaru , Wada Hiroshi , Fujita Hideo
Published: November 2021

In percutaneous coronary intervention (PCI) to the culprit lesion of acute myocardial infarction (AMI), unsuccessful guidewire crossing causes immediate poor outcomes. It is important to determine the factors associated with unsuccessful guidewire crossing in AMI lesions. The purpose of this study was to find factors associated with difficulty in crossing the culprit lesion of AMI. We defined the difficult group when the guidewire used to cross the culprit lesion was a polymer jacket type guidewire or a stiff guidewire. We included 937 patients, and divided those into the non-difficult group (n = 876) and the difficult group (n = 61). Proximal reference diameter was significantly smaller in the difficult group than in the non-difficult group (p < 0.001), and degree of calcification was severer in the difficult group than in the non-difficult group (p < 0.001). In the multivariate stepwise logistic regression analysis, proximal reference diameter [odds ratio (OR) 0.313, 95% confidence interval (CI) 0.185–0.529, p < 0.001)], previous PCI (OR 3.065, 95% CI 1.612–5.830, p = 0.001), moderate-severe calcification (OR 4.322, 95% CI 2.354–7.935, p < 0.001), blunt type obstruction (OR 12.646, 95% CI 6.805–23.503, p < 0.001), and the presence of collateral to the culprit lesion (OR 2.110, 95% CI 1.145–3.888, p = 0.017) were significantly associated with difficulty in crossing the culprit lesion. In conclusion, previous PCI, calcification, blunt type obstruction, and the presence of collateral were associated with difficulty in crossing the culprit lesion, whereas proximal reference diameter was inversely associated with difficulty. Our study provides a reference to recognize the difficulty in crossing the culprit lesions of AMI for PCI operators, especially junior operators.
Wolbachia detection in Aedes aegypti using MALDI-TOF MS coupled to artificial intelligence
Authors: Rakotonirina Antsa , Caruzzo Cédric , Ballan Valentine , Kainiu Malia , Marin Marie , Colot Julien , Richard Vincent , Dupont-Rouzeyrol Myrielle , Selmaoui-Folcher Nazha , Pocquet Nicolas
Published: November 2021

The mosquito Aedes aegypti is the major vector of arboviruses like dengue, Zika and chikungunya viruses. Attempts to reduce arboviruses emergence focusing on Ae. aegypti control has proven challenging due to the increase of insecticide resistances. An emerging strategy which consists of releasing Ae. aegypti artificially infected with Wolbachia in natural mosquito populations is currently being developed. The monitoring of Wolbachia-positive Ae. aegypti in the field is performed in order to ensure the program effectiveness. Here, the reliability of the Matrix‑Assisted Laser Desorption Ionization‑Time Of Flight (MALDI‑TOF) coupled with the machine learning methods like Convolutional Neural Network (CNN) to detect Wolbachia in field Ae. aegypti was assessed for the first time. For this purpose, laboratory reared and field Ae. aegypti were analyzed. The results showed that the CNN recognized Ae. aegypti spectral patterns associated with Wolbachia-infection. The MALDI-TOF coupled with the CNN (sensitivity = 93%, specificity = 99%, accuracy = 97%) was more efficient than the loop-mediated isothermal amplification (LAMP), and as efficient as qPCR for Wolbachia detection. It therefore represents an interesting method to evaluate the prevalence of Wolbachia in field Ae. aegypti mosquitoes.
High molecular weight glutenin gene diversity in Aegilops tauschii demonstrates unique origin of superior wheat quality
Authors: Delorean Emily , Gao Liangliang , Lopez Jose Fausto Cervantes ,   Open Wild Wheat Consortium, Mehrabi Ali , Bentley Alison , Sharon Amir , Keller Beat , Wulff Brande , Steffenson Brian , Steuernagel Burkhard , Sansaloni Carolina Paola , Liu Deng-Cai , Lagudah Evans , Nasyrova Firuza , Brown-Guedira Gina , Sela Hanan , Dvorak Jan , Poland Jesse , Mayer Klaus , Krasileva Ksenia , Gaurav Kumar , Mao Long , Caccamo Mario , Mascher Martin , Luo Mingcheng , Chhuneja Parveen , Davey Rob , Faris Justin , Xu Steven , Nicholson Paul , Chayut Noam , Ambrose Mike , Rawat Nidhi , Tiwari Vijay K. , Wulff Brande B. H. , Ibba Maria Itria , Poland Jesse
Published: November 2021

Central to the diversity of wheat products was the origin of hexaploid bread wheat, which added the D-genome ofAegilops tauschiito tetraploid wheat giving rise to superior dough properties in leavened breads. The polyploidization, however, imposed a genetic bottleneck, with only limited diversity introduced in the wheat D-subgenome. To understand genetic variants for quality, we sequenced 273 accessions spanning the known diversity ofAe. tauschii. We discovered 45 haplotypes inGlu-D1, a major determinant of quality, relative to the two predominant haplotypes in wheat. The wheat allele2 + 12was found inAe. tauschiiLineage 2, the donor of the wheat D-subgenome. Conversely, the superior quality wheat allele5 + 10allele originated in Lineage 3, a recently characterized lineage ofAe. tauschii, showing a unique origin of this important allele. These two wheat alleles were also quite similar relative to the total observed molecular diversity inAe. tauschiiatGlu-D1.Ae. tauschiiis thus a reservoir for uniqueGlu-D1alleles and provides the genomic resource to begin utilizing new alleles for end-use quality improvement in wheat breeding programs.
Design principles and biological applications of red-emissive two-photon carbon dots
Authors: Lesani Pooria , Mohamad Hadi Aina Hazeera , Lu Zufu , Palomba Stefano , New Elizabeth J. , Zreiqat Hala
Published: November 2021

Carbon dots have been gaining attention in the field of nanobiotechnology due to their superior photostability, high water solubility, ease of synthesis and surface functionalization, chemical inertness, low toxicity, and excellent biocompatibility. They also exhibit good two-photon absorption and unique tunable optical properties across a wide range of wavelengths, from ultraviolet to near infrared endowing them with potential for a variety of biological applications. Recently, there has been a growing interest in the synthesis and development of red-emissive two-photon carbon dots. Here we present recent progress in the design requirements for red-emissive two-photon carbon dots, and review current state-of-the-art systems, covering their applications in bioimaging, biosensing, and photothermal and photodynamic therapy.
Automated QuEChERS for the determination of 482 pesticide residues in Radix codonopsis by GC-Q-TOF/MS and LC-Q-TOF/MS
Authors: Chang Qiaoying , Ge Lijuan , Li Jian , Qiu Guoyu , Wu Fuxiang , Zhang Hongyan , Xu Fenghua , Zhu Renyuan , Qi Pengfei , Bai Ruobin , Ren Fazheng
Published: November 2021

A rapid and automated QuEChERS procedure has been developed for high-throughput screening of 482 pesticide residues in Radix codonopsis by GC-Q-TOFMS and LC-Q-TOFMS.
Two-dimensional porphyrin covalent organic frameworks with tunable catalytic active sites for the oxygen reduction reaction
Authors: Yue Jie-Yu , Wang Yu-Tong , Wu Xin , Yang Peng , Ma Yu , Liu Xuan-He , Tang Bo
Published: November 2021

Four novel two-dimensional porphyrin COFs (M-TP-COF, M = H2, Co, Ni and Mn) with donor–acceptor dyads were fabricated and served as electrocatalysts for the oxygen reduction reaction (ORR).
Ir(iii)-Catalysed electrooxidative intramolecular dehydrogenative C–H/N–H coupling for the synthesis of N–H indoles
Authors: Kim Youyoung , Kim Dongwook , Chang Sukbok
Published: November 2021

Iridium-catalysed electrooxidative cyclisation of 2-alkenyl anilines is developed to obtain unprotected N–H indole products.
Graphene-based nano-devices: high spin Seebeck and pure spin photogalvanic effects
Authors: Dong Yaojun , Tao Xixi , Wang Lihua , Wu Yinzhong , Yu Ning , Bai Long , Wang Xuefeng , Yang Xifeng , Liu Yushen
Published: November 2021

We investigate the magnetic, thermoelectric transport, and photogalvanic effect (PGE) properties of two nano-devices based on sawtooth edged graphene nanoribbons (SGNRs).
Plasmonic MoO2 embedded MoNi4 nanosheets prepared by NiMoO4 transformation for visible-light-enhanced 4-nitrophenol reduction
Authors: Deng Liujun , Zou Yu , Jiang Jiang
Published: November 2021

Plasmonic MoO2 embedded MoNi4 nanosheets have been synthesized by reductive transformation of NiMoO4 and used as a catalyst in the light-enhanced 4-nitrophenol reduction reaction.
Covalent sortase A inhibitor ML346 prevents Staphylococcus aureus infection of Galleria mellonella
Authors: Guan Xiang-Na , Zhang Tao , Yang Teng , Dong Ze , Yang Song , Lan Lefu , Gan Jianhua , Yang Cai-Guang
Published: November 2021

Covalent sortase A inhibitor ML346 prevents Galleria mellonella from Staphylococcus aureus infection by interfering in the transpeptidation activity of sortase A for anchoring surface proteins into staphylococci envelope.
MoS2/cellulose-doped ZnO nanorods for catalytic, antibacterial and molecular docking studies
Authors: Ikram Muhammad , Imran Muhammad , Hayat Shoukat , Shahzadi Anum , Haider Ali , Naz Sadia , Ul-Hamid Anwar , Nabgan Walid , Fazal Iqra , Ali Salamat
Published: November 2021

Cellulose nanocrystals (CNCs) and molybdenum disulphide (MoS2) incorporated into ZnO nanorods (NRs) were synthesized via a chemical precipitation route at room temperature.
Quantifying the effect of PEG architecture on nanoparticle ligand availability using DNA-PAINT
Authors: Andrian Teodora , Pujals Silvia , Albertazzi Lorenzo
Published: November 2021

The importance of PEG architecture on nanoparticle (NP) functionality is known but still difficult to investigate. Here, DNA-PAINT and qPAINT are used to quantify this phenomenon at a single particle and molecular level.
Super-resolution FRET measurements
Authors: Szalai Alan M. , Zaza Cecilia , Stefani Fernando D.
Published: November 2021

Recent advances combining FRET and super-resolution techniques are presented. This merger of methods is opening exciting opportunities to study the spatial organization and functional state of (bio)molecules and materials at the nanoscale.
Photoinduced assembly of the 3,4,4a,7a-tetrahydro-1H-cyclopenta[b]pyridine-2,7-dione core on the basis of allomaltol derivatives
Authors: Milyutin Constantine V. , Galimova Renata D. , Komogortsev Andrey N. , Lichitskii Boris V. , Melekhina Valeriya G. , Migulin Vasily A. , Fakhrutdinov Artem N. , Minyaev Mikhail E.
Published: November 2021

A novel photochemical synthetic pathway to various substituted 3,4,4a,7a-tetrahydro-1H-cyclopenta[b]pyridine-2,7-diones based on readily available allomaltol derivatives containing an amide group was developed.
Targetable nano-delivery vehicles to deliver anti-bacterial small acid-soluble spore protein (SASP) genes
Authors: Barnard Anne M. L. , Cass James A.
Published: November 2021

Interest in phage-based therapeutics is increasing, at least in part due to the need for new treatment options for infections caused by antibiotic-resistant bacteria. It is possible to use wild-type (WT) phages to treat bacterial infections, but it is also possible to modify WT phages to generate therapeutics with improved features. Here, we will discuss features of Phico Therapeutics’ SASPject technology, which modifies phages for use as targetable nano-delivery vehicles (NDV), to introduce antibacterial Small Acid Soluble Spore Protein (SASP) genes into specific target bacteria.
Error Refactor loss based on error analysis in image classification
Authors: Yu Xiaoyu , Chen Yinglu , Zhou Guofu , Liu Yan , Li Fuchao , Wang Zhifei
Published: November 2021

The loss function is a criterion to evaluate the learning quality of a deep convolutional neural network, which represents the gap between prediction and ground truth. However, as the most commonly used loss function in image classification tasks, Cross‐Entropy loss does not encourage the model to distinguish the similarity between features. In this work, the authors investigate inter‐class separability of similar features learnt by convolutional networks and propose a loss function called Error Refactor Loss (ER‐Loss). ER‐Loss is based on the error caused by convolutional networks; it can improve the inter‐class separability and is simple to implement and can easily replace the Cross‐Entropy loss. Compared with softmax loss, ER‐Loss adds a dynamic penalty item which can help ER‐Loss monitor the actual situation of model training and adjust the value of the penalty item according to model training. The ER‐Loss on CIFAR100 and part of ImageNet ILSVRC 2012 is evaluated and the experimental result showed that the ER‐Loss can improve the accuracy of the model.
Statistical properties of Hα jets in the polar coronal hole and their implications in coronal activities
Authors: Qi Youqian , Huang Zhenghua , Xia Lidong , Fu Hui , Guo Mingzhe , Hou Zhenyong , Liu Weixin , Sun Mingzhe , Liu Dayang
Published: November 2021

Context. Dynamic features such as chromospheric jets, transition region network jets, coronal plumes, and coronal jets are abundant in the network regions of polar coronal holes on the Sun.

Aims. We investigate the relationship between chromospheric jets and coronal activities, such as coronal plumes and jets.

Methods. We analyzed observations of a polar coronal hole including the filtergrams taken by the New Vacuum Solar Telescope at the Hα − 0.6 Å to study the Hα jets, as well as the Atmospheric Imaging Assembly 171 Å images to follow the evolution of coronal activities.

Results. The Hα jets are persistent in the network regions, with only some regions (denoted as R1–R5) rooted in discernible coronal plumes. With an automated method, we identified and tracked 1320 Hα jets in the network regions. We find that the average lifetime, height, and ascending speed of the Hα jets are 75.38 s, 2.67 Mm, 65.60 km s−1, respectively. The Hα jets rooted in R1–R5 are higher and faster than those in the others. We also find that propagating disturbances (PDs) in coronal plumes have a close connection with the Hα jets. The speeds of 28 out of 29 Hα jets associated with PDs are ≳50 km s−1. In the case of a coronal jet, we find that the speeds in both the coronal jet and the Hα jet are over 150 km s−1, suggesting that both cool and hot jets can be coupled.

Conclusions. Based on our analyses, it is evident that more dynamic Hα jets could release their energy to the corona, which might be the result of a Kelvin-Helmholtz instability developing or that of small-scale magnetic activities. We suggest that chromospheric jets, transition region network jets, and ray-like features in the corona are coherent phenomena that serve as important vehicles for cycling energy and mass in the solar atmosphere.
Modeling the Mg I from the NUV to MIR
Authors: Peralta J. I. , Vieytes M. C. , Mendez A. M. P. , Mitnik D. M.
Published: November 2021

Context. Semi-empirical models of the solar atmosphere are used to study the radiative environment of any planet in our Solar System. There is a need for reliable atomic data for neutral atoms and ions in the atmosphere to obtain improved calculated spectra. Atomic parameters are crucial to computing the correct population of elements through the whole stellar atmosphere. Although there is very good agreement between the observed and calculated spectra for the Sun, there is still a mismatch in several spectral ranges due to the lack of atomic data and the inaccuracies thereof, particularly for neutrals such as Mg I.

Aims. To represent many spectral lines of Mg I from the near-ultraviolet to the mid-infrared correctly, it is necessary to add and update the atomic data involved in the atomic processes that drive their formation.

Methods. The improvements made to the Mg I atomic model are as follows: i) 127 strong lines, including their broadening data, were added. ii) To obtain these new lines, we increased the number of energy levels from 26 to 85. iii) Photoionization cross-section parameters were added and updated. iv) Effective collision strength (ϒij) parameters were updated for the first 25 levels using the existing data from the convergent close-coupling calculations. One of the most significant changes in our model is given by the new ϒij parameters for transitions involving levels between 26 and 54, which were computed with a multiconfiguration Breit–Pauli distorted-wave (DW) method. For transitions involving superlevels, we calculated the ϒij parameters with the usual semi-empirical formulas.

Results. More than 100 transitions were added to our calculations, increasing our capability of reproducing important features observed in the solar spectra. We found a remarkable improvement in matching the solar spectra for wavelengths higher than 30 000 Å when our new DW ϒij data were used in the model.
Modeling and measurement of precision reducers' efficiency curve
Authors: Xu Hang , Gao Jinfeng , He Yuanchun , Xie Guiping , Wu Yaoting
Published: November 2021

Transmission efficiency is the key index when concerning characterizing the performance of precision reducers, and it is usually required to be measured and evaluated. Apart from that, the efficiency value at the rated torque in the efficiency curve is taken as the evaluation value of the efficiency characteristics of precision reducers. However, at present, the research on the efficiency characteristics of precision reducers mainly focuses on theoretical analysis, the development of measurement devices and the measurement methods, while the analysis model of the efficiency curve has not yet been established. In this context, from the perspective of transmission efficiency measurement and evaluation of precision reducers, the efficiency calculation model of precision reducers is established in this paper. Besides, based on the essential change law of the efficiency curve, the efficiency curve analysis model is also set up. To be specific, taking a certain type of RV (rotate vector) reducer as an example, the actual measurement experiments are carried out, and the efficiency curves at different speeds are obtained. The results show that the efficiency of the precision reducer is affected by the measured speed and load torque, and has a positive correlation with the load torque and a negative correlation with the speed. Then, it is proved that the efficiency curve model proposed in this paper can accurately describe the change law followed by the efficiency curve of precision reducers, thus laying a theoretical foundation for the efficiency measurement and evaluation of precision reducers.
Soil contamination by Echinococcus multilocularis in rural and urban vegetable gardens in relation to fox, cat and dog faecal deposits
Authors: Da Silva Abdou Malik , Bastien Matthieu , Umhang Gérald , Boué Franck , Bastid Vanessa , Boucher Jean-Marc , Caillot Christophe , de Garam Carine Peytavin , Renault Camille , Faisse Marine , Courquet Sandra , Scalabrino Vincent , Millon Laurence , Knapp Jenny , Poulle Marie-Lazarine
Published: November 2021

Echinococcus multilocularis eggs are deposited on the ground with the faeces of the carnivore definitive hosts. A reliable assessment of the spatial distribution of E. multilocularis eggs in environments used by humans is crucial for the prevention of alveolar echinococcosis (AE). This study was conducted in 192 rural and 71 urban vegetable gardens in AE endemic areas of north-eastern France. Its objective was to explore the relationship between the spatial distribution of E. multilocularis estimated from the collection and molecular analysis of two types of samples: faeces and soil. A total of 1024 carnivore faeces and 463 soil samples were collected and analysed by real-time PCR. No fox droppings and no positive soil samples were collected from the urban gardens. Positive soil samples, positive carnivore faeces, or both, were found in 42%, 24% and 6% of the sampled rural gardens, respectively. No significant association was found between the detection of E. multilocularis in soil samples collected from 50 gardens during a single sampling session and the extent and frequency of deposits of fox and cat faeces collected during repeated sampling sessions conducted in the previous months. In 19/50 gardens, E. multilocularis was detected in the soil while no positive faeces had been collected in the previous 12 months. Conversely, in 8/50 gardens, no soil samples were positive although positive faeces had been collected in the previous months. Collecting and analysing faeces provide information on soil contamination at a given time, while analysing soil samples provides an overview of long-term contamination.
Evaluation of valence band offset and its non-commutativity at all oxide α-Cr2O3/β-Ga2O3 heterojunction from photoelectron spectroscopy
Authors: Ghosh Sahadeb , Baral Madhusmita , Bhattacharjee Jayanta , Kamparath Rajiv , Singh S. D. , Ganguli Tapas
Published: November 2021

We have investigated the non-commutativity of the band offset in RF magnetron sputter deposited all oxide epitaxial α-Cr2O3/β-Ga2O3 heterojunction (HJ). The core-level x-ray photoelectron spectroscopy technique has been employed to probe the electronic structure of the interface formed between α-Cr2O3 and β-Ga2O3. Valence and conduction band offsets of 2.6 ± 0.2 and 0.9 ± 0.2 eV, respectively, for α-Cr2O3/β-Ga2O3 HJ have been determined from Kraut's method. These values are different from those reported for β-Ga2O3/α-Cr2O3 HJ, thus indicating that the α-Cr2O3/β-Ga2O3 HJ does not follow the band commutativity with respect to the growth sequence of the constituting layers forming the HJ. Furthermore, the band alignment at α-Cr2O3/β-Ga2O3 HJ is still type-II like β-Ga2O3/α-Cr2O3 HJ but with lower band offset values. Therefore, this HJ would also be able to confine the electrons and holes in β-Ga2O3 and α-Cr2O3 layers, respectively, with lower turn on voltage.
Wireless power transfer in attenuating media
Authors: Chu S. , Stevens C. J. , Shamonina E.
Published: November 2021

Dissipative media (underground/underwater, biological materials and tissues, etc.) pose a challenge to inductive wireless power transfer systems as they generally attenuate the near fields that enable mutual coupling. Apart from this, the impact of the environment on electromagnetic fields can also be seen in the self-impedance of coils, resulting in significant eddy current losses and detuning effects. In this article, we study, theoretically, the mechanism of wireless power transfer via a pair of magnetic resonators inside an infinite homogeneous medium with a comprehensive circuit model that takes into account all the electromagnetic effects of the background medium. This analytical approach can offer deep insights into the design and operation of wireless charging systems in non-ideal environments.
Comparison of algorithms for predicting plasma physical parameters of SF6–Cu mixtures at local thermodynamic equilibrium state via machine learning
Authors: Ding Can , Ding Qingchang , Wang Zhenyi , Zhou Yiyuan , Chen Chen
Published: November 2021

In order to study the arc process of the SF6 circuit breaker during the current breaking process, it is necessary to calculate the physical parameters of the arc discharge plasma. However, the calculation of plasma physical parameters is very difficult and complicated and generally requires solving dozens of differential equations. Based on the machine learning method, this paper constructs a learning prediction model of physical property parameters in a local thermodynamic equilibrium state without solving a large number of differential equations so as to perform a rapid prediction of physical property parameters in other scenarios based on the existing physical parameter database. This paper uses the support vector machine, K-nearest neighbor algorithm, gradient boosting regression, decision tree, and random forest algorithm to predict and calculate the thermodynamic parameters and transport characteristics of SF6 at different pressures and temperatures. At the same time, this paper also predicts and calculates the parameters of the SF6–Cu mixed gas at different mixed concentrations. The results show that the machine learning algorithm can predict and generate consistent gas property parameter data, indicating that the model has good generalization performance. Finally, by comparing the error measures of the prediction results of various algorithms, the algorithm suitable for predicting the physical parameters is found to improve the prediction accuracy.
A simplified rapid-quench multi-anvil technique
Authors: Bondar Dmitry , Fei Hongzhan , Withers Anthony C. , Ishii Takayuki , Chanyshev Artem , Katsura Tomoo
Published: November 2021

We report a new rapid-quench technique for the Kawai-type multi-anvil press: several important improvements were made to our previous design. As a result, we are able to routinely quench melts with low glass-forming ability and form glasses. Owing to the use of 3D-printed parts to supply the coolant, the new design is easier to assemble and demonstrates better temperature stability and cooling rate. It was also found that the cooling rate is both pressure- and temperature-dependent. The cooling rate increases with increasing pressure from 6700 °C/s at 1 GPa to 8200 °C/s at 5.5 GPa and decreases with increasing temperature at a rate of 550 °C s−1/100 °C. Taking these dependencies into account, the new rapid-quench design produces more than 15% higher cooling rate compared to the previous design. Moreover, enhancing coolant circulation, which was achieved by using tapered inner anvils with holes, additionally increases the cooling rate by about 4%. As the structure of the rapid-quench assembly differs dramatically from other existing designs, pressure calibration and temperature distribution in the experimental cell and sample capsule were determined for the first time. It was found that the first 0.6 MN of press load is not used to generate pressure due to the hard tungsten components in the assembly. At the current state-of-the-art, it is possible to routinely reach a pressure of 9 GPa and a temperature of 2200 K with the temperature variation not exceeding 70 K within the sample capsule.
Identification and correction of miscalibration artifacts based on force noise for optical tweezers experiments
Authors: Freitag Marvin , Kamp Dieter , Synakewicz Marie , Stigler Johannes
Published: November 2021

Single-molecule force spectroscopy using optical tweezers continues to provide detailed insights into the behavior of nanoscale systems. Obtaining precise measurements of their mechanical properties is highly dependent on accurate instrument calibration. Therefore, instrumental drift or inaccurate calibration may prevent reaching an accuracy at the theoretical limit and may lead to incorrect conclusions. Commonly encountered sources of error include inaccuracies in the detector sensitivity and trap stiffness and neglecting the non-harmonicity of an optical trap at higher forces. Here, we first quantify the impact of these artifacts on force-extension data and find that a small deviation of the calibration parameters can already have a significant downstream effect. We then develop a method to identify and remove said artifacts based on differences in the theoretical and measured noise of bead fluctuations. By applying our procedure to both simulated and experimental data, we can show how effects due to miscalibration and trap non-linearities can be successfully removed. Most importantly, this correction can be performed post-measurement and could be adapted for data acquired using any force spectroscopy technique.
Living up to its potential—Direct-write nanofabrication with focused electron beams
Authors: Huth Michael , Porrati Fabrizio , Barth Sven
Published: November 2021

Over its rather long history, focused electron beam induced deposition (FEBID) has mostly been used as an auxiliary process in passivating surfaces in sample preparation for transmission electron microscopy. This has changed over the last one and a half decades. On the one hand, FEBID has been established as the leading technical approach to lithography mask repair on the industrial scale. On the other hand, FEBID-related technical and methodological developments, FEBID-derived materials, and FEBID-based device fabrication have had a significant impact in various areas of basic and applied research, such as nanomagnetism and superconductivity, plasmonics, and sensing. Despite this dynamic development, the FEBID user base does still form a rather exclusive club of enthusiasts. In this Perspective, our aim is to provide sufficient insight into the basics of FEBID, its potential, as well as its challenges, to scientists working in the broader fields of materials science, nanotechnology, and device development. It is our hope to spark growing interest and even excitement into FEBID which, as we believe, still has to live up to its full potential.
Jumping and hysteresis effect in 1–1-typed magnetoelectric resonators
Authors: Chu Zhaoqiang , Gao Junqi , Sun Zechen , Mao Zhineng , Zhang Shuangjie , Shen Ying , Dong Shuxiang
Published: November 2021

Multiferroic magnetoelectric (ME) composites have been continually attracting researchers' attention because of the significant potential for building functional devices. Unlike conventional ME devices under quasi-static or low-power excitation, e.g., sensors, energy harvesters, and random memories, high-power ME devices like recently proposed ME antennas will perform complex dynamic behavior. The voltage-driven nonlinearity in 1–1-typed ME resonators was reported from the perspective of frequency-response curve in our last work. Here, we described both theoretically and experimentally a previously unobserved jumping and hysteresis effect in its magnetic bias characteristic. A direct link between the bias-response and the frequency-response characteristics was also experimentally provided to analyze the origin of the nonlinear behavior in the bias-response curve. In addition, the cubic spring constant k3 was theoretically calculated and compared to qualitatively explain the difference of our obtained threshold voltage that generated the first and second jumping resonances in the dual-peak bias-response curve. In contrast to our previous research, this work reveals the loading direction of the applied magnetic bias field, which plays a significant role when we consider the selection of an optimized bias field for high-power ME devices. Moreover, the sharp jumping in the bias-response curve is also a potential for opening dimensions for ME community.
Influence of compressibility on the development of streamwise supersonic corner flow
Authors: Yang Run-ze , Yang Rui , Zhao Yu-xin
Published: November 2021

The effect of compressibility on supersonic corner flow is numerically investigated by the Reynolds-averaged Navier–Stokes equations with a full Reynolds stress model. A grid sensitivity analysis is conducted in this paper to ensure the reliability of our conclusions. Then, a parametric study by changing the Mach number in the range of M∞=0.6−3.0 is carried out to investigate the effect of compressibility. The corner angle is also changed in the range of θ=45°−135° for each M∞ to see the effect of the corner angle. As a result, the Mach number was found to have a negligible effect on the propagation of vortex cores in this study. However, it has a positive effect on both the friction coefficient and the total pressure loss. The geometrical transformation for the position of the vortex center proposed in our recent paper has been proved to be valid in over wide range. Moreover, we further find that a unified formula can describe the distribution of the total pressure loss under different Mach numbers and corner angles. In engineering terms, these laws will play an important role in the initial design and evaluation of the project with streamwise corners.
Floating of dia-, para-, and superparamagnetic bodies in magnetic fluids: Analysis of wall effects in the framework of inductive approach
Authors: Ivanov Aleksey S. , Pshenichnikov Alexandr F. , Khokhryakova Christina A. , Somov Sergey A. , Koskov Mikhail A.
Published: November 2021

Laboratory experiments and numerical simulations were carried out to investigate physical patterns and main characteristics of the magnetic ponderomotive buoyancy force acting on solid dia-, para-, and superparamagnetic bodies immersed in cylindrical containers filled with magnetic fluids and magnetized by a uniform magnetic field. The experimental measurements of the magnetic buoyancy force validated with numerical simulations are reliable enough for use in the benchmark testing of various applications (ferrofluid sensors, measuring devices, separators, etc.). It is shown that the superparamagnetic bodies have one (stable) equilibrium position in the center of the container in virtue of the fact that the ponderomotive force is monotonous. The non-magnetic bodies have an unstable equilibrium position in the center of the container and the force is non-monotonous with two extrema due to the competition between two mechanisms: the inhomogeneous demagnetizing field inside the cylindrical container, and the interaction of the non-magnetic body dipole with its own mirror image. Due to this competition, the force can change its direction depending on the geometry of the container, the applied magnetic field, and the nonlinear ferrofluid magnetization law. The results demonstrate that the non-magnetic bodies may be in stable equilibrium near the container walls only if two independent conditions are met: the gradient demagnetizing field is weak (the container is wide or quasi-ellipsoidal), and the applied field is weak (the ferrofluid magnetization curve is quasi-linear). If any of these conditions is abandoned, then the non-magnetic body is unable to levitate and falls on the container wall.
A simple imaging solution for chip-scale laser cooling
Authors: Bregazzi A. , Griffin P. F. , Arnold A. S. , Burt D. P. , Martinez G. , Boudot R. , Kitching J. , Riis E. , McGilligan J. P.
Published: November 2021

We demonstrate a simple stacked scheme that enables absorption imaging through a hole in the surface of a grating magneto-optical trap (GMOT) chip, placed immediately below a micro-fabricated vacuum cell. The imaging scheme is capable of overcoming the reduced optical access and surface scatter that is associated with this chip-scale platform while further permitting both trapping and imaging of the atoms from a single incident laser beam. The through-hole imaging is used to characterize the impact of the reduced optical overlap volume of the GMOT in the chip-scale cell, with an outlook to an optimized atom number in low volume systems.
Optomechanical temporal sampling of terahertz signals
Authors: Chomet Baptiste , Gacemi Djamal , Vasanelli Angela , Sirtori Carlo , Todorov Yanko
Published: November 2021

Various detection schemes are currently investigated in the terahertz frequency range (<2 THz), as an alternative to the widespread bolometers and Golay cells that feature very high sensitivity but low modulation frequencies (<10 kHz). In this work, we report an alternative concept based on an optomechanical detector able to read out an arbitrary periodic modulation imprinted on a terahertz beam. The detector is a based on a combination of a split-ring resonator, acting as a terahertz antenna, and a high-quality mechanical resonator with typical resonant frequency ω0/2π = 1 MHz. We demonstrate two methods for Fourier sampling the envelope of the terahertz signal, in which the mechanical resonator is used as a reference oscillator. With our methods, signals with an arbitrary period T can be sampled, even those that are much faster than the oscillation period of the mechanical resonator, 1/T ≫ ω0.
Reshaping plasmonic resonances using epsilon-near-zero materials for enhanced infrared vibrational spectroscopy
Authors: Smaali Rafik , Taliercio Thierry , Moreau Antoine , Centeno Emmanuel
Published: November 2021

Surface-enhanced infrared absorption (SEIRA) spectroscopy is a powerful technique for a label-free identification of molecular species. The low infrared absorption cross sections of molecules are made up for the huge electromagnetic field enhancement provided by the resonant excitation of collective electron oscillations in metallic nanoantennas. Since these surface plasmons are localized at the nanometer scale, a minute amount of materials is detected leading to a weak SEIRA signal. The design of actual plasmonics detectors is a trade-off between the detection of very small volumes of molecules and the signal to noise ratio level. We demonstrate that an epsilon-near-zero (ENZ) material combined with nano-slits lifts this constraint and provides both extreme enhancement factor up to 107 and highly contrasted SEIRA signal for an extremely low amount of material of interest. These results are explained by the modification of the electromagnetic field of the gap plasmon mode sustained by the slits in the presence of the ENZ material. We propose to implement this concept with a semiconductor whose doping level engineering provides a versatile way to scan the whole molecules' fingerprint frequency range.
Two-stage energy auction model and strategy among multiple microgrids for trading incentives and default management
Authors: Jiang Aihua , Wang Haojie , Pan Xiaowu
Published: November 2021

The lack of trust caused by rigid pricing strategies, third-party participation, and transaction default may lead to a decline in transaction willingness and misgivings about the availability of resources among microgrids (MGs). In particular, if large-scale transaction default occurs, it may endanger the safe and stable operation of the power grid. In this paper, a two-stage energy auction model based on blockchain and smart contracts to solve the problem of lack of trust and transaction default, and to increase flexibility in energy transactions among microgrids is proposed. The novelty of the proposed method lies in the transaction incentives and management of payment defaults through smart contracts and the partition management of buyer MGs' energy demands. Partitioning energy demands in the first stage of the auction can increase the diversity of sellers' bidding in the second stage. A credit management model based on the completion of historical transactions is designed to manage defaults. The priority factor affecting transaction order and energy allocation is designed to incentivize transactions. The introduction of blockchain can reduce dependence on trusted third parties and solve the security and privacy issues of transactions. Smart contracts are used to host the entire process of the auction and record, calculate the priority of each microgrid before the auction starts, and allocate energy fairly. In the energy delivery stage, the smart contract determines whether there is a default and automatically realizes the transfer of transaction funds, avoiding any selfish behavior in the transaction. Finally, we verify the effectiveness of the above-mentioned trading method through numerical analysis.
Nonadiabatic geometric quantum computation with shortened path on superconducting circuits
Authors: Ding Cheng-Yun , Liang Yan , Yu Kai-Zhi , Xue Zheng-Yuan
Published: November 2021

Recently, nonadiabatic geometric quantum computation has received much attention due to its fast manipulation and intrinsic error-resilience characteristics. However, to obtain universal geometric quantum control, only limited and special evolution paths have been proposed, which usually require longer gate-time and more operational steps, and thus lead to lower quality of the implemented quantum gates. Here, we present an effective scheme to find the shortest geometric path under conventional conditions of geometric quantum computation, where high-fidelity and robust geometric gates can be realized by only single-loop evolution, and the gate performances are better than the corresponding dynamical ones. Furthermore, we can optimize the pulse shapes in our scheme to further shorten the gate-time, which is determined by how fast the path is traveled. In addition, we also present its physical implementation on superconducting circuits, consisting of capacitively coupled transmon qubits, where fidelities of geometric single- and two-qubit gates can be higher than 99.95% and 99.80% within the current state-of-the-art experimental technologies, respectively. These results indicate that our scheme is promising for large-scale fault-tolerant quantum computation.
Interactions between Görtler vortices and the second mode in hypersonic boundary layer
Authors: Huang Ganglei
Published: November 2021

The interaction between Görtler vortices and the second mode is experimentally investigated in a Mach 6.5 quiet wind tunnel by using the CO2-enhanced filtered Rayleigh-scattering technique combined with fast-response pressure sensors. The results show that, for an appropriate amplitude of Görtler vortices (i.e., sufficiently low to avoid triggering a secondary instability), they stabilize the second mode. To the best of the author's knowledge, this is the first time that the stabilization of the second mode by Görtler vortices is detected experimentally in the hypersonic flow.
A sprinkling of scientists prioritizes behaviors to counter climate change
Authors: Feder Toni
Published: November 2021

Can steps like less travel and more talk advance science and serve as an example to the public?
Idaho project tests the limits of DOE aid to advanced reactors
Authors: Kramer David
Published: November 2021

The department says the Versatile Test Reactor is vital to the future of the US nuclear industry. Critics say it is duplicative and that industry should help pay for it.
The demons haunting thermodynamics
Authors: Robertson Katie
Published: November 2021

The contradictory implications of statistical mechanics have worried physicists and philosophers for centuries. Does our present-day knowledge allow us to exorcize those philosophical demons?
Aerodynamic heating in hypersonic flows
Authors: Smith Charles R.
Published: November 2021

A newly discovered mechanism can help keep the world’s fastest jets from overheating.
Preventing translational inhibition from ribosomal protein insufficiency by a herpes simplex virus–encoded ribosome-associated protein
Authors: Vink Elizabeth I. , Andrews John , Duffy Carol , Mohr Ian
Published: November 2021

In addition to being required for protein synthesis, ribosomes and ribosomal proteins (RPs) also regulate messenger RNA translation in uninfected and virus-infected cells. By individually depleting 85 RPs using RNA interference, we found that overall protein synthesis in uninfected primary fibroblasts was more sensitive to RP depletion than those infected with herpes simplex virus-1 (HSV-1). Although representative RP depletion (uL3, uS4, uL5) inhibited protein synthesis in cells infected with two different DNA viruses (human cytomegalovirus, vaccinia virus), HSV-1–infected cell protein synthesis unexpectedly endured and required a single virus-encoded gene product, VP22. During individual RP insufficiency, VP22-expressing HSV-1 replicated better than a VP22-deficient variant. Furthermore, VP22 promotes polysome accumulation in virus-infected cells when uL3 or ribosome availability is limiting and cosediments with initiating and elongating ribosomes in infected and uninfected cells. This identifies VP22 as a virus-encoded, ribosome-associated protein that compensates for RP insufficiency to support viral protein synthesis and replication. Moreover, it reveals an unanticipated class of virus-encoded, ribosome-associated effectors that reduce the dependence of protein synthesis upon host RPs and broadly support translation during physiological stress such as infection.
Cryo-EM structures of PI3Kα reveal conformational changes during inhibition and activation
Authors: Liu Xiao , Yang Su , Hart Jonathan R. , Xu Yingna , Zou Xinyu , Zhang Huibing , Zhou Qingtong , Xia Tian , Zhang Yan , Yang Dehua , Wang Ming-Wei , Vogt Peter K.
Published: November 2021

Significance

Phosphoinositide 3-kinases (PI3Ks) are of critical importance in cell signaling and can function as drivers of disease. Information on the PI3K structure is essential for an understanding of the function of these proteins and for the identification of specific and effective small-molecule inhibitors. Here we present a single-particle cryo-electron microscopy (cryo-EM) analysis of PI3Kα, the dimer consisting of the p110α catalytic subunit bound to the p85α regulatory subunit. We investigated three conformational states of PI3Kα: the unbound dimer, the dimer bound to the isoform-specific inhibitor BYL-719, and the dimer associated with an activating phosphopeptide. Each of these conformations reveals specific structural features that provide insights into conformation-associated functions.
Thermochronologic perspectives on the deep-time evolution of the deep biosphere
Authors: Drake Henrik , Reiners Peter W.
Published: November 2021

Significance

The Earth’s deep biosphere is one of the least explored and understood environments. It hosts microbial lineages that are of interest for understanding the origin and evolution of life on our planet. Understanding the history of these microbial communities requires assessing the complex evolution of habitable conditions. This study presents the first thermochronological perspective on the habitability of Earth’s Precambrian cratons through time and suggests that the longest record of continuous habitability to the present does not stretch much beyond 1 billion years. This thermochronologic approach provides context for prospecting and interpreting the little-explored geologic record of the deep biosphere of Earth’s cratons and points to candidate areas for the oldest records of subsurface microorganisms.
Quantifying contributions of natural variability and anthropogenic forcings on increased fire weather risk over the western United States
Authors: Zhuang Yizhou , Fu Rong , Santer Benjamin D. , Dickinson Robert E. , Hall Alex
Published: November 2021

Significance

The western United States (WUS) has experienced a rapid increase of fire weather (as indicated by vapor pressure deficit, VPD) in recent decades, especially in the warm season. However, the extent to which an increase of VPD is due to natural variability or anthropogenic warming has been unclear. Our observation-based estimate suggests ∼one-third of the VPD trend is attributable to natural variability of atmospheric circulation, whereas ∼two-thirds is explained by anthropogenic warming. In addition, climate models attribute ∼90% of the VPD trend to anthropogenic warming. Both estimates suggest that anthropogenic warming is the main cause for increasing fire weather and provide a likely range for the true anthropogenic contribution to the WUS trend in VPD.
Gate-tunable magnetoresistance in six-septuple-layer MnBi2Te4
Authors: Li Yaoxin , Liu Chang , Wang Yongchao , Li Hao , Wu Yang , Zhang Jinsong , Wang Yayu
Published: November 2021

The recently discovered antiferromagnetic topological insulator MnBi2Te4 hosts many exotic topological quantum phases such as the axion insulator and the Chern insulator. Here we report on systematic gate-voltage-dependent magneto-transport studies in six-septuple-layer MnBi2Te4. In the p-type carrier regime, we observe positive linear magnetoresistance (MR) when MnBi2Te4 is polarized in the ferromagnetic state by an out-of-plane magnetic field. Whereas in the n-type regime, distinct negative MR behaviors are observed. The behaviors of magnetoresistance in both regimes are highly robust against temperature up to the Néel temperature. Within the antiferromagnetic regime, the behavior of MR exhibits a transition from negative to positive under the control of gate voltage. The boundaries of the MR phase diagram can be explicitly marked by the gate-voltage-independent magnetic fields that characterize the processes of the spin-flop transition. The rich transport phenomena demonstrate the intricate interplay between topology, magnetism and dimensionality in MnBi2Te4.