bluuebunny/crossref_metadata_2025 huggingface dataset:
Giant second harmonic transport under time-reversal symmetry in a trigonal superconductor
Authors: Itahashi Yuki M. , Ideue Toshiya , Hoshino Shintaro , Goto Chihiro , Namiki Hiromasa , Sasagawa Takao , Iwasa Yoshihiro
Published: March 2022

Nonreciprocal or even-order nonlinear responses in symmetry-broken systems are powerful probes of emergent properties in quantum materials, including superconductors, magnets, and topological materials. Recently, vortex matter has been recognized as a key ingredient of giant nonlinear responses in superconductors with broken inversion symmetry. However, nonlinear effects have been probed as excess voltage only under broken time-reversal symmetry. In this study, we report second harmonic transport under time-reversal symmetry in the noncentrosymmetric trigonal superconductor PbTaSe2. The magnitude of anomalous nonlinear transport is two orders of magnitude larger than those in the normal state, and the directional dependence of nonlinear signals are fully consistent with crystal symmetry. The enhanced nonlinearity is semiquantitatively explained by the asymmetric Hall effect of vortex-antivortex string pairs in noncentrosymmetric systems. This study enriches the literature on nonlinear phenomena by elucidating quantum transport in noncentrosymmetric superconductors.
Rho-dependent transcription termination proceeds via three routes
Authors: Song Eunho , Uhm Heesoo , Munasingha Palinda Ruvan , Hwang Seungha , Seo Yeon-Soo , Kang Jin Young , Kang Changwon , Hohng Sungchul
Published: March 2022

Rho is a general transcription termination factor in bacteria, but many aspects of its mechanism of action are unclear. Diverse models have been proposed for the initial interaction between the RNA polymerase (RNAP) and Rho (catch-up and stand-by pre-terminational models); for the terminational release of the RNA transcript (RNA shearing, RNAP hyper-translocation or displacing, and allosteric models); and for the post-terminational outcome (whether the RNAP dissociates or remains bound to the DNA). Here, we use single-molecule fluorescence assays to study those three steps in transcription termination mediated by E. coli Rho. We find that different mechanisms previously proposed for each step co-exist, but apparently occur on various timescales and tend to lead to specific outcomes. Our results indicate that three kinetically distinct routes take place: (1) the catch-up mode leads first to RNA shearing for RNAP recycling on DNA, and (2) later to RNAP displacement for decomposition of the transcriptional complex; (3) the last termination usually follows the stand-by mode with displacing for decomposing. This three-route model would help reconcile current controversies on the mechanisms.
Neural relational inference to learn long-range allosteric interactions in proteins from molecular dynamics simulations
Authors: Zhu Jingxuan , Wang Juexin , Han Weiwei , Xu Dong
Published: March 2022

Protein allostery is a biological process facilitated by spatially long-range intra-protein communication, whereby ligand binding or amino acid change at a distant site affects the active site remotely. Molecular dynamics (MD) simulation provides a powerful computational approach to probe the allosteric effect. However, current MD simulations cannot reach the time scales of whole allosteric processes. The advent of deep learning made it possible to evaluate both spatially short and long-range communications for understanding allostery. For this purpose, we applied a neural relational inference model based on a graph neural network, which adopts an encoder-decoder architecture to simultaneously infer latent interactions for probing protein allosteric processes as dynamic networks of interacting residues. From the MD trajectories, this model successfully learned the long-range interactions and pathways that can mediate the allosteric communications between distant sites in the Pin1, SOD1, and MEK1 systems. Furthermore, the model can discover allostery-related interactions earlier in the MD simulation trajectories and predict relative free energy changes upon mutations more accurately than other methods.
Cube attacks on round-reduced TinyJAMBU
Authors: Teng Wil Liam , Salam Iftekhar , Yau Wei-Chuen , Pieprzyk Josef , Phan Raphaël C.-W.
Published: March 2022

Lightweight cryptography has recently gained importance as the number of Internet of things (IoT) devices connected to Internet grows. Its main goal is to provide cryptographic algorithms that can be run efficiently in resource-limited environments such as IoT. To meet the challenge, the National Institute of Standards and Technology (NIST) announced the Lightweight Cryptography (LWC) project. One of the finalists of the project is the TinyJAMBU cipher. This work evaluates the security of the cipher. The tool used for the evaluation is the cube attack. We present five distinguishing attacks DA1–DA5 and two key recovery attacks KRA1–KRA2. The first two distinguishing attacks (DA1 and DA2) are launched against the initialisation phase of the cipher. The best result achieved for the attacks is a distinguisher for an 18-bit cube, where the cipher variant consists of the full initialisation phase together with 438 rounds of the encryption phase. The key recovery attacks (KRA1 and KRA2) are also launched against the initialisation phase of the cipher. The best key recovery attack can be applied for a cipher variant that consists of the full initialisation phase together with 428 rounds of the encryption phase. The attacks DA3–DA5 present a collection of distinguishers up to 437 encryption rounds, whose 32-bit cubes are chosen from the plaintext, nonce, or associated data bits. The results are confirmed experimentally. A conclusion from the work is that TinyJAMBU has a better security margin against cube attacks than claimed by the designers.
Detection of subclinical keratoconus using a novel combined tomographic and biomechanical model based on an automated decision tree
Authors: Song Peng , Ren Shengwei , Liu Yu , Li Pei , Zeng Qingyan
Published: March 2022

Early detection of keratoconus is a crucial factor in monitoring its progression and making the decision to perform refractive surgery. The aim of this study was to use the decision tree technique in the classification and prediction of subclinical keratoconus (SKC). A total of 194 eyes (including 105 normal eyes and 89 with SKC) were included in the double-center retrospective study. Data were separately used for training and validation databases. The baseline variables were derived from tomography and biomechanical imaging. The decision tree models were generated using Chi-square automatic interaction detection (CHAID) and classification and regression tree (CART) algorithms based on the training database. The discriminating rules of the CART model selected metrics of the Belin/Ambrósio deviation (BAD-D), stiffness parameter at first applanation (SPA1), back eccentricity (Becc), and maximum pachymetric progression index in that order; On the other hand, the CHAID model selected BAD-D, deformation amplitude ratio, SPA1, and Becc. Further, the CART model allowed for discrimination between normal and SKC eyes with 92.2% accuracy, which was higher than that of the CHAID model (88.3%), BAD-D (82.0%), Corvis biomechanical index (CBI, 77.3%), and tomographic and biomechanical index (TBI, 78.1%). The discriminating performance of the CART model was validated with 92.4% accuracy, while the CHAID model was validated with 86.4% accuracy in the validation database. Thus, the CART model using tomography and biomechanical imaging was an excellent model for SKC screening and provided easy-to-understand discriminating rules.
Acute pancreatitis or severe increase in pancreatic enzyme levels following remdesivir administration in COVID-19 patients: an observational study
Authors: Miyazaki Kazuhito , Yoshimura Yukihiro , Miyata Nobuyuki , Sasaki Hiroaki , Shiba Aya , Aga Masaharu , Hamakawa Yusuke , Taniguchi Yuri , Misumi Yuki , Agemi Yoko , Shimokawa Tsuneo , Okamoto Hiroaki , Tachikawa Natsuo
Published: March 2022

Remdesivir has been shown to reduce recovery time and mortality among patients with coronavirus disease 2019 (COVID-19). However, data regarding the efficacy and safety of remdesivir use are limited in Japan. We conducted a single-center retrospective cohort study at Yokohama Municipal Citizen’s Hospital, Kanagawa, Japan. Patients with COVID-19 pneumonia treated with remdesivir were included. The onset of acute pancreatitis and increased pancreatic enzyme levels and clinical, laboratory, treatment, and outcome data were collected and analyzed. A total of 201 patients were included. Among the 201 patients treated with remdesivir, 177 recovered from COVID-19. Increased pancreatic enzyme levels of grade 3 or higher or acute pancreatitis developed in 23 of the 201 patients. The potential etiopathogenetic effects of remdesivir on increased pancreatic enzyme levels of grade 3 or higher or acute pancreatitis were ascertained by reviewing the characteristics of patients hospitalized for COVID-19 who did not receive remdesivir treatment. Only 3 of 159 patients had increased pancreatic enzyme levels of grade 3 or higher during the treatment course. Multivariate analysis indicated remdesivir administration and severe COVID-19 infection by National Institute of Health standards as independent risk factors. Acute pancreatitis and severe increases in pancreatic enzyme levels were observed among patients with COVID-19 treated with remdesivir.
Optical biosensors using plasmonic and photonic crystal band-gap structures for the detection of basal cell cancer
Authors: Khani Shiva , Hayati Mohsen
Published: March 2022

One of the most interesting topics in bio-optics is measuring the refractive index of tissues. Accordingly, two novel optical biosensor configurations for cancer cell detections have been proposed in this paper. These structures are composed of one-dimensional photonic crystal (PC) lattices coupled to two metal–insulator–metal (MIM) plasmonic waveguides. Also, the tapering method is used to improve the matching between the MIM plasmonic waveguides and PC structure in the second proposed topology. The PC lattices at the central part of the structures generate photonic bandgaps (PBGs) with sharp edges in the transmission spectra of the biosensors. These sharp edges are suitable candidates for sensing applications. On the other hand, the long distance between two PBG edges causes that when the low PBG edge is used for sensing mechanism, it does not have an overlapping with the high PBG edge by changing the refractive index of the analyte. Therefore, the proposed biosensors can be used for a wide wavelength range. The maximum obtained sensitivities and FOM values of the designed biosensors are equal to 718.6, 714.3 nm/RIU, and 156.217, 60.1 RIU−1, respectively. The metal and insulator materials which are used in the designed structures are silver, air, and GaAs, respectively. The finite-difference time-domain (FDTD) method is used for the numerical investigation of the proposed structures. Furthermore, the initial structure of the proposed biosensors is analyzed using the transmission line method to verify the FDTD simulations. The attractive and simple topologies of the proposed biosensors and their high sensitivities make them suitable candidates for biosensing applications.
The association between diabetes and hypertension with the number and extent of weight cycles determined from 6 million participants
Authors: Kim Su Hwan , Kwak Jin-Seul , Kim Seong Pyo , Choi Sung Hyouk , Yoon Hyung-Jin
Published: March 2022

The purpose of this study was to elucidate the association between weight cycling and clinical outcomes such as type 2 diabetes and hypertension with differential effects of baseline age and obesity. Nationwide data from 6,132,569 healthy adults who underwent five or more health screenings between 2002 and 2011 were analyzed and followed until December 2019 for type 2 diabetes and hypertension. Weight cycling was defined as a change in body weight followed by another change in the opposite direction. Through the Cox proportional hazards model, the number and degree of weight cycles were positively associated with increased risk of type 2 diabetes and hypertension. The hazard ratios (HRs) of weight cycling for type 2 diabetes and hypertension were as high as 1.263 (1.213–1.315) and 1.175 (1.144–1.207) at two or more weight cycles of 10% of body weight (BW), respectively. The association was stronger for females, individuals with normal body weight/BMI, and older individuals. Weight cycling was significantly associated with an increased risk of adverse health outcomes and was stronger in individuals with normal BMI and females, indicating that these people should be informed about the potential risk of weight cycling.
Automatic MRI segmentation of pectoralis major muscle using deep learning
Authors: Godoy Ivan Rodrigues Barros , Silva Raian Portela , Rodrigues Tatiane Cantarelli , Skaf Abdalla Youssef , de Castro Pochini Alberto , Yamada André Fukunishi
Published: March 2022

To develop and validate a deep convolutional neural network (CNN) method capable of selecting the greatest Pectoralis Major Cross-Sectional Area (PMM-CSA) and automatically segmenting PMM on an axial Magnetic Resonance Imaging (MRI). We hypothesized a CNN technique can accurately perform both tasks compared with manual reference standards. Our method is based on two steps: (A) segmentation model, (B) PMM-CSA selection. In step A, we manually segmented the PMM on 134 axial T1-weighted PM MRIs. The segmentation model was trained from scratch (MONAI/Pytorch SegResNet, 4 mini-batch, 1000 epochs, dropout 0.20, Adam, learning rate 0.0005, cosine annealing, softmax). Mean-dice score determined the segmentation score on 8 internal axial T1-weighted PM MRIs. In step B, we used the OpenCV2 (version 4.5.1,https://opencv.org) framework to calculate the PMM-CSA of the model predictions and ground truth. Then, we selected the top-3 slices with the largest cross-sectional area and compared them with the ground truth. If one of the selected was in the top-3 from the ground truth, then we considered it to be a success. A top-3 accuracy evaluated this method on 8 axial T1-weighted PM MRIs internal test cases. The segmentation model (Step A) produced an accurate pectoralis muscle segmentation with a Mean Dice score of 0.94 ± 0.01. The results of Step B showed top-3 accuracy > 98% to select an appropriate axial image with the greatest PMM-CSA. Our results show an overall accurate selection of PMM-CSA and automated PM muscle segmentation using a combination of deep CNN algorithms.
Parental education related to their children’s health in late childhood and early adolescence for Pacific families within New Zealand
Authors: Schluter Philip J. , Kokaua Jesse , Tautolo El-Shadan , Iusitini Leon , Richards Rosalina , Ruhe Troy
Published: March 2022

Pacific people continue to carry a disproportionately heavy social and health burden relative to their non-Pacific peers in New Zealand, and those with less formal education are experiencing social and health declines. Improving education and educational needs is seen as being central to decreasing these health inequities. While expansive, the empirical evidence-base supporting this stance is relatively weak and increasingly conflicting. Using a large birth cohort of 1,368 eligible Pacific children, together with their mothers and fathers, this study longitudinally investigates the relationship between paternal education levels and sentinel measures of their children’s physical health, mental health and health risk taking behaviours during late childhood and early adolescence. In adjusted analyses, it was found that mothers and fathers who undertook further schooling over the 0–6 years postpartum period had children with significantly lower logarithmically transformed body mass index increases at 11-years and 14-years measurement waves compared to 9-years levels than those who did not study (p = 0.017 and p = 0.022, respectively). Furthermore, fathers who undertook further schooling over this 0–6 years postpartum period also had children with significantly lower odds of risk taking behaviours (p = 0.013). These results support policy aimed at increasing educational opportunities for Pacific people in New Zealand.
Hydrogen phosphate selectively induces MDA MB 231 triple negative breast cancer cell death in vitro
Authors: Shanti Aya , Al Adem Kenana , Stefanini Cesare , Lee Sungmun
Published: March 2022

Phosphate ions are the most abundant anions inside the cells, and they are increasingly gaining attention as key modulators of cellular function and gene expression. However, little is known about the effect of inorganic phosphate ions on cancer cells, particularly breast cancer cells. Here, we investigated the toxicity of different phosphate compounds to triple-negative human breast cancer cells, particularly, MDA-MB-231, and compared it to that of human monocytes, THP-1. We found that, unlike dihydrogen phosphate (H2PO4−), hydrogen phosphate (HPO42−) at 20 mM or lower concentrations induced breast cancer cell death more than immune cell death, mainly via apoptosis. We correlate this effect to the fact that phosphate in the form of HPO42−raises pH levels to alkaline levels which are not optimum for transport of phosphate into cancer cells. The results in this study highlight the importance of further exploring hydrogen phosphate (HPO42−) as a potential therapeutic for the treatment of breast cancer.
Inhibition of triple negative breast cancer-associated inflammation, tumor growth and brain colonization by targeting monoacylglycerol lipase
Authors: Benchama Othman , Tyukhtenko Sergiy , Malamas Michael S. , Williams Mark K. , Makriyannis Alexandros , Avraham Hava Karsenty
Published: March 2022

While the prevalence of breast cancer metastasis in the brain is significantly higher in triple negative breast cancers (TNBCs), there is a lack of novel and/or improved therapies for these patients. Monoacylglycerol lipase (MAGL) is a hydrolase involved in lipid metabolism that catalyzes the degradation of 2-arachidonoylglycerol (2-AG) linked to generation of pro- and anti-inflammatory molecules. Here, we targeted MAGL in TNBCs, using a potent carbamate-based inhibitor AM9928 (hMAGL IC50 = 9 nM) with prolonged pharmacodynamic effects (46 h of target residence time). AM9928 blocked TNBC cell adhesion and transmigration across human brain microvascular endothelial cells (HBMECs) in 3D co-cultures. In addition, AM9928 inhibited the secretion of IL-6, IL-8, and VEGF-A from TNBC cells. TNBC-derived exosomes activated HBMECs resulting in secretion of elevated levels of IL-8 and VEGF, which were inhibited by AM9928. Using in vivo studies of syngeneic GFP-4T1-BrM5 mammary tumor cells, AM9928 inhibited tumor growth in the mammary fat pads and attenuated blood brain barrier (BBB) permeability changes, resulting in reduced TNBC colonization in brain. Together, these results support the potential clinical application of MAGL inhibitors as novel treatments for TNBC.
Scalable and accurate multi-GPU-based image reconstruction of large-scale ptychography data
Authors: Yu Xiaodong , Nikitin Viktor , Ching Daniel J. , Aslan Selin , Gürsoy Doğa , Biçer Tekin
Published: March 2022

While the advances in synchrotron light sources, together with the development of focusing optics and detectors, allow nanoscale ptychographic imaging of materials and biological specimens, the corresponding experiments can yield terabyte-scale volumes of data that can impose a heavy burden on the computing platform. Although graphics processing units (GPUs) provide high performance for such large-scale ptychography datasets, a single GPU is typically insufficient for analysis and reconstruction. Several works have considered leveraging multiple GPUs to accelerate the ptychographic reconstruction. However, most of these works utilize only the Message Passing Interface to handle the communications between GPUs. This approach poses inefficiency for a hardware configuration that has multiple GPUs in a single node, especially while reconstructing a single large projection, since it provides no optimizations to handle the heterogeneous GPU interconnections containing both low-speed (e.g., PCIe) and high-speed links (e.g., NVLink). In this paper, we provide an optimized intranode multi-GPU implementation that can efficiently solve large-scale ptychographic reconstruction problems. We focus on the maximum likelihood reconstruction problem using a conjugate gradient (CG) method for the solution and propose a novel hybrid parallelization model to address the performance bottlenecks in the CG solver. Accordingly, we have developed a tool, called PtyGer (Ptychographic GPU(multiple)-based reconstruction), implementing our hybrid parallelization model design. A comprehensive evaluation verifies that PtyGer can fully preserve the original algorithm’s accuracy while achieving outstanding intranode GPU scalability.
Oryzanol alleviates high fat and cholesterol diet-induced hypercholesterolemia associated with the modulation of the gut microbiota in hamsters
Authors: Yan Sisi , Chen Jihong , Zhu Lingfeng , Guo Tianyi , Qin Dandan , Hu Zuomin , Han Shuai , Wang Ji , Matias Froilan Bernard , Wen Lixin , Luo Feijun , Lin Qinlu
Published: March 2022

A high fat and cholesterol diet (HFCD) can modulate the gut microbiota, which is closely related with hypercholesterolemia.
Retraction: Controllable color emission of platinum(ii) complexes and their application in light-emitting diodes (LEDs)
Authors: Li Bao-Ning , Wang Jia-Jun , Fu Peng-Yan , Wang Shi-Cheng , Pan Mei
Published: March 2022

Retraction of ‘Controllable color emission of platinum(ii) complexes and their application in light-emitting diodes (LEDs)’ by Bao-Ning Li et al., J. Mater. Chem. C, 2021, DOI: 10.1039/d1tc01398j.
Route planning for electric vehicles
Authors: Ben Abbes Sirine , Rejeb Lilia , Baati Lasaad
Published: March 2022

This work addresses the multi‐objective route planning and charging problem for Battery Electric Vehicles (BEVs). The proposed solution is based on the NSGA‐II algorithm to derive the Pareto‐optimal set of eco‐routes with the minimum travel and charging time, distance, energy consumption and charging costs while complying with the constraints related to the battery State of Charge (SoC) and the status of charging stations. Influencing factors, such as, vehicle and battery parameters, weather conditions, driver behaviour, road grade, Time Of Use (TOU) electricity cost, and Charging Stations (CS) status and type, are taken into account. The final results of the proposed method are compared with the well‐established simulator SUMO.
A simplified sliding‐mode control method for multi‐level transformerless DVR
Authors: Komurcugil Hasan , Bayhan Sertac , Guler Naki , Abu‐Rub Haitham , Bagheri Farzaneh
Published: March 2022

Here, a finite‐control‐set sliding‐mode control (FCS‐SMC) method is proposed for single‐phase three‐level T‐type inverter‐based transformerless dynamic voltage restorers (TDVRs). The inherent advantages of SMC (fast dynamic response and high robustness) are combined with FCS concept to increase the effectiveness of the method in achieving the desired control objectives. First, the use of FCS eliminates the modulator requirement, which reduces the design complexity in the practical implementation. Second, an effective method based on charging/discharging conditions of DC capacitors is proposed for balancing capacitor voltages using relevant switching state rather than combining DC voltage error with the inductor current error through a suitable weighting factor in forming the cost function. Therefore, the weighting factor necessity in the control algorithm is eliminated. Finally, the steady‐state error in the compensation voltage is eliminated by the proportional‐resonant (PR) controller. The studied T‐type inverter‐based TDVR topology offers an alternative solution to the existing DVR topologies. Experimental results are carried out to demonstrate the effectiveness of the proposed FCS‐SMC method in maintaining the load voltage at the desired level despite the voltage sags, swells, and distortions occurring in the grid voltage.
Generalized and symmetric coprime planar array for direction of arrival estimation
Authors: Ren Ming Jian , Hu Guoping , Shi Junpeng , Zhou Hao
Published: March 2022

Degrees of freedom and mutual coupling are two important factors to determine the ability of direction of arrival (DOA) estimation. Although coprime planar array (CPPA) has less mutual coupling than hourglass array (HA) and ladder array (LA), its positive and negative covariance corresponding lags are discontinuous, resulting in low degrees of freedom. In this study, we propose a generalized and symmetric coprime planar array (GSCA) by employing the symmetric property of the difference co‐array. By moving one subarray and introducing a supplementary subarray, we construct a connected virtual uniform rectangular array (URA). Through further optimizing the sensor number, the redundant lags are reduced and the array structure is more general. We show that the degrees of freedom are much higher than those of CPPA, HA and LA. Besides, the mutual coupling is close to CPPA, but less than HA and LA. The superiority of GSCA is verified by simulations.
The CARMENES search for exoplanets around M dwarfs
Authors: Quirrenbach A. , Passegger V. M. , Trifonov T. , Amado P. J. , Caballero J. A. , Reiners A. , Ribas I. , Aceituno J. , Béjar V. J. S. , Chaturvedi P. , González-Cuesta L. , Henning T. , Herrero E. , Kaminski A. , Kürster M. , Lalitha S. , Lodieu N. , López-González M. J. , Montes D. , Pallé E. , Perger M. , Pollacco D. , Reffert S. , Rodríguez E. , López C. Rodríguez , Shan Y. , Tal-Or L. , Osorio M. R. Zapatero , Zechmeister M.
Published: March 2022

The CARMENES radial-velocity survey is currently searching for planets in a sample of 387 M dwarfs. Here we report on two Saturn-mass planets orbiting TYC 2187-512-1 (M* = 0.50 M⊙) and TZ Ari (M* = 0.15 M⊙), respectively. We obtained supplementary photometric time series, which we use along with spectroscopic information to determine the rotation periods of the two stars. In both cases, the radial velocities also show strong modulations at the respective rotation period. We thus modeled the radial velocities as a Keplerian orbit plus a Gaussian process representing the stellar variability. TYC 2187-512-1 is found to harbor a planet with a minimum mass of 0.33 MJup in a near-circular 692-day orbit. The companion of TZ Ari has a minimum mass of 0.21 MJup, orbital period of 771 d, and orbital eccentricity of 0.46. We provide an overview of all known giant planets in the CARMENES sample, from which we infer an occurrence rate of giant planets orbiting M dwarfs with periods up to 2 yr in the range between 2 and 6%. TZ Ari b is only the second giant planet discovered orbiting a host with mass less than 0.3 M⊙. These objects occupy an extreme location in the planet mass versus host mass plane. It is difficult to explain their formation in core-accretion scenarios, so they may possibly have been formed through a disk fragmentation process.
Microlensing and the type Ia supernova iPTF16geu
Authors: Diego J. M. , Bernstein G. , Chen W. , Goobar A. , Johansson J. P. , Kelly P. L. , Mörtsell E. , Nightingale J. W.
Published: March 2022

The observed magnifications and light curves of the quadruply imaged iPTF16geu supernova (SN) offers a unique opportunity to study a lens system with a variety of independent constraints. The four observed positions can be used to constrain the macrolens model. The magnifications and light curves at the four SN positions are more useful to constrain microlensing models. We define the macrolens model as a combination of a baryonic component that traces the observed light distribution, and a dark matter halo component. We constrained the macrolens model using the positional constraints given by the four observed images, and compared it with the best model obtained when magnification constraints were included. We found that the magnification cannot be explained by a macrolens model alone, and that contributions from substructures such as microlenses are needed to explain the observed magnifications. We considered microlens models based on the inferred stellar mass from the baryonic component of the macrolens model, and used the observed magnification and light curves to constrain the contribution from microlenses. We computed the likelihood of a variety of macro and micro lens models where we varied the dark matter halo, baryonic component, and microlens configurations. We used information about the position, magnification, and, for the first time, the light curves of the four observed SN images. We combined macrolens and microlens models in order to reproduce the observations; the four SN positions, magnifications, and lack of fluctuations in the light curves. After marginalizing over the model parameters, we found that larger stellar surface mass densities are preferred. This result suggests that the mass of the baryonic component is dominated by its stellar component. We conclude that microlensing from the baryonic component suffices to explain the observed flux ratios and light curves.
Virtual four sensor fast response aerodynamic probe (FRAP®)
Authors: Pfau Axel , Schlienger Joel , Kalfas Anestis I. , Abhari Reza S.
Published: March 2022

This paper introduces the new fast response aerodynamic probe (FRAP®), which was recently developed at the ETH Zurich. The probe provides time-resolved, three-dimensional flow measurements using the virtual four sensor technique. Two probes work in tandem, being comparable to a pair of pneumatic needle probes. The first probe, being yaw angle sensitive, is positioned in three circumferential positions. The second probe being pitch angle sensitive is brought into exactly the same position as the first probe. The resulting set of four measurements is phaselock-averaged to one specific rotor trigger position. Then the reduced data sets are combined to four calibration coefficients, which are then further processed to determine the unsteady flow vector. The results consist of yaw and pitch flow angles as well as the total and static pressure. The outer diameter of the cylindrical probe head was miniaturized to 0.84mm, hence probe blockage effects as well as dynamic lift effects are reduced. The shape of the probe head was optimized in view of the manufacturing process as well as aerodynamic considerations. The optimum geometry for pitch sensitivity was found to be a cylindrical surface with the axis perpendicular to the probe shaft. The internal design of the probes led to a sensor cavity eigen frequency of 44 kHz for the yaw sensitive and 34kHz for the pitch sensitive probe. The steady aerodynamic characteristics of the probe were measured using the free jet probe calibration facility of the laboratory. The full set of calibration surfaces is given. Data acquisition is done with a fully automated traversing system, which moves the probe within the test rig and samples the signal with a PC-based A/D-board. An error analysis implemented into the data reduction routines revealed acceptable accuracy for flow angles as well as pressures for many turbomachinery flows. Depending on the dynamic head of the application the yaw angle is accurate within ±0.35° and pitch angle within ±0.7°. Finally, a comparison of time averaged results to five hole probe measurements is discussed.
Evaluation of pressure and species concentration measurement using uncertainty propagation
Authors: Stefopoulos Georgios , Rigas Stylianos , Tsirikoglou Panagiotis , Kalfas Anestis I.
Published: March 2022

This paper presents a probabilistic uncertainity evaluation method as described in the Guide to the Expression of Uncertainty in Measurements (GUM) and its application to probe measurements on pressure and fuel concentration. All sources of unceratinties are expressed as probability distributions. Consequently, the overall standard uncertainty of the quantity can be calculated using the Gaussian error propagation formula. The result of the uncertainty evaluation yields the most probable value of the measurand and describes its distribution in terms of rectangular (standard uncertainty) or gaussian (“expanded” uncertainty) distribution. A pitot-static probe and a fuel-concentration stem probe are used in order to demonstrate the principle of the probabilistic uncertainty evaluation method. The uncertainty induced by the pressure and concentration data acquisition system as well as the calibration of the fuel-concentration probe are included in the analysis. The overall “expanded” uncertainties for the measured and calculated values are presented as a function of different inlet fuel flows. In addition to this, the individual sources of uncertainty to the overall standard uncertainty are presented and discussed. Moreover, the transformation of standard uncertainty to “expanded” uncertainty will provide the deviation of the measurement in a 95% or 99% normal distributed interval instead of a 67% rectangular distributed interval.
High resolution laser excitation spectra and Franck-Condon factors of A2Π−X2Σ+ electronic transition of MgF
Authors: Gu Jingwang , Xiao Zengjun , Yu Chunting , Zhang Qiang , Chen Yang , Zhao Dongfeng
Published: March 2022

Magnesium monofluoride (MgF) is proposed as an ideal candidate radical for direct laser cooling. Here, the rotationally resolved laser spectra of MgF for the A2Π−X2Σ+ electronic transition system were recorded by using laser induced fluorescence technique. The MgF radicals were produced by discharging SF6/Ar gas mixtures between the tips of two magnesium needles in a supersonic jet expansion. We recorded a total of 19 vibrational bands belonging to three sequences of Δv=0, ±1 in the region of 348-370 nm. Accurate spectroscopic constants for both X2Σ+ and A2Π states are determined from rotational analysis of the experimental spectra. Spectroscopic parameters, including the Franck-Condon factors (FCFs), are determined from the experimental results and the Rydberg-Klein-Rees (RKR) calculations. Significant discrepancies between the experimentally measured and RKR-calculated FCFs are found, indicating that the FCFs are nearly independent of the spin-orbit coupling in the A2Π state. Potential energy curves (PECs) and FCFs determined here provide necessary data for the theoretical simulation of the laser-cooling scheme of MgF.
Solvent effects on excited-state relaxation dynamics of paddle-wheel BODIPY-Hexaoxatriphenylene conjugates: Insights from non-adiabatic dynamics simulations
Authors: Chen Wen-Kai , Cui Ganglong , Liu Xiang-Yang
Published: March 2022

Understanding the excited state dynamics of donor-acceptor (D-A) complexes is of fundamental importance both experimentally and theoretically. Herein, we have first explored the photoinduced dynamics of a recently synthesized paddle-wheel BODIPY-hexaoxatriphenylene (BODIPY is the abbreviation for BF2-chelated dipyrromethenes) conjugates D-A complexes with the combination of both electronic structure calculations and non-adiabatic dynamics simulations. On the basis of computational results, we concluded that the BODIPY-hexaoxatriphenylene (BH) conjugates will be promoted to the local excited (LE) states of the BODIPY fragments upon excitation, which is followed by the ultrafast exciton transfer from LE state to charge transfer (CT). Instead of the photoinduced electron transfer process proposed in previous experimental work, such a exciton transfer process is accompanied with the photoinduced hole transfer from BODIPY to hexaoxatriphenylene. Additionally, solvent effects are found to play an important role in the photoinduced dynamics. Specifically, the hole transfer dynamics is accelerated by the acetonitrile solvent, which can be ascribed to significant influences of the solvents on the charge transfer states, i.e. the energy gaps between LE and CT excitons are reduced greatly and the non-adiabatic couplings are increased in the meantime. Our present work not only provides valuable insights into the underlying photoinduced mechanism of BH, but also can be helpful for the future design of novel donor-acceptor conjugates with better optoelectronic performance.
Basis sets dependency in constructing spectroscopy-accuracy Ab Initio global electric dipole moment functions
Authors: Zhai Yu , Li Hui
Published: March 2022

Recently, more attention have been paid on the construction of dipole moment functions (DMF) using theoretical methods. However, the computational methods to construct DMFs are not validated as much as those for potential energy surfaces do. In this letter, using Ar ⋯ He as an example, we tested how spectroscopy-accuracy DMFs can be constructed using ab initio methods. We especially focused on the basis set dependency in this scenario, i.e., the convergence of DMF with the sizes of basis sets, basis set superposition error, and mid-bond functions. We also tested the explicitly correlated method, which converges with smaller basis sets than the conventional methods do. This work can serve as a pictorial sample of all these computational technologies behaving in the context of constructing DMFs.
N2O plasma treatment effect on reliability of p-GaN gate AlGaN/GaN HEMTs
Authors: Park Jun Hyuk , Hwang Sun-Kyu , Kim Joonyong , Jeon Woochul , Hwang Injun , Oh Jaejoon , Kim Boram , Park Younghwan , Shin Dong-Chul , Park Jong-Bong , Kim Jongseob
Published: March 2022

This work investigates the effect of N2O plasma treatment on the reliability of p-GaN gate AlGaN/GaN high-electron-mobility transistors (HEMTs), specifically in the AlGaN drift region. The formation of a GaON/AlON compound layer on the AlGaN surface after N2O plasma treatment was confirmed by energy-dispersive x-ray spectroscopy mapping and x-ray photoelectron spectroscopy analysis. When a device is under highly stressed conditions, the compound layer reduces the number of negatively charged interface traps and protects the AlGaN surface by hindering the Ga-out diffusion. The high temperature reverse bias reliability test demonstrated that the N2O plasma treatment enhanced the reliability of p-GaN gate HEMTs by suppressing the degradation of the on-resistance from 18.7% to 9.0%, after being subjected to a high drain bias (VDS = 700 V) at 200 °C for 1000 s.
Aerodynamic characteristics of MIRA automobile model based on fluid–structure coupling
Authors: Wang Zewei , Hu Xingjun , Hui Zheng , Yu Guo , Lan Wei , Liu Fei
Published: March 2022

In this paper, the aerodynamic characteristics of a vehicle model are analyzed through numerical simulation considering the fluid–structure interaction (FSI) effect, and the accuracy of the simulation method is verified by comparison with the wind tunnel experiment. Then, the wind-induced vibration of vehicles under time-varying crosswind is studied and applied to engineering problems, such as vehicle sideslip and roll. The results show that the deviation between the FSI simulation and wind tunnel test is less than 10%, proving that the numerical method is feasible. The FSI effect on the aerodynamic lift is obvious, and its influence mechanism is mainly due to the change in body position, which changes the topological structure of the shedding or separated vortex in the flow field. As for the aerodynamic lift, a big gap exists between the results of the numerical simulations with and without coupling; high-intensity side wind will seriously affect the vehicle stability, and the uncoupled numerical simulation decreases the accuracy of the vehicle design.
Acceptor traps as the source of holes in p-type N-polar GaN/(AlN/AlGaN) superlattices
Authors: Krishna Athith , Raj Aditya , Hatui Nirupam , Keller Stacia , Denbaars Steven , Mishra Umesh K
Published: March 2022

This study experimentally shows the existence of acceptor traps at positive polarization interfaces (PPIs) acting as the source of holes in N-polar p-type modulation doped GaN/(AlN/AlGaN) superlattices (SLs) with low Mg doping. The observation of measured hole concentration higher than the dopants (here, Mg) put in the samples during growth can be explained by the ionization of acceptor traps, which are placed 0.8 eV above the valence band of GaN at the PPI. All samples were epitaxially grown using metal organic chemical vapor deposition and were characterized using x-ray diffraction and room-temperature Hall measurements. The measured hole concentrations are compared against calculated values from STR FETIS®, and the measured mobility trends are explained using the separation of the positive polarization interfaces from the two-dimensional hole gas in the systems, strengthening the hypothesis. A second study is also presented where acceptor traps were ionized in a p-type modulation doped GaN/AlGaN SL without an AlN layer—by keeping the superlattice period thickness constant and increasing the AlGaN composition. Following the hypothesis of the existence of an acceptor trap, these experimental studies demonstrate the charge-balance in systems that show p-type behavior without sufficient doping.
Geometry optimizations with spinor-based relativistic coupled-cluster theory
Authors: Zheng Xuechen , Zhang Chaoqun , Liu Junzi , Cheng Lan
Published: March 2022

Development of analytic gradients for relativistic coupled-cluster singles and doubles augmented with a non-iterative triples [CCSD(T)] method using an all-electron exact two-component Hamiltonian with atomic mean-field spin–orbit integrals (X2CAMF) is reported. This enables efficient CC geometry optimizations with spin–orbit coupling included in orbitals. The applicability of the implementation is demonstrated using benchmark X2CAMF-CCSD(T) calculations of equilibrium structures and harmonic vibrational frequencies for methyl halides, CH3X (X = Br, I, and At), as well as calculations of rotational constants and infrared spectrum for RaSH+, a radioactive molecular ion of interest to spectroscopic study.
Non-equilibrium characteristics of mass and heat transfers in the slip flow
Authors: Zhang Yudong , Xu Aiguo , Chen Feng , Lin Chuandong , Wei Zon-Han
Published: March 2022

Slip flow is a common phenomenon in micro-/nano-electromechanical systems. It is well known that the mass and heat transfers in slip flow show many unique behaviors, such as the velocity slip and temperature jump near the wall. However, the kinetic understanding of slip flow is still an open problem. This paper first clarifies that the Thermodynamic Non-Equilibrium (TNE) flows can be roughly classified into two categories: near-wall TNE flows and TNE flows away from the wall. The origins of TNE in the two cases are significantly different. For the former, the TNE mainly results from the fluid–wall interaction; for the latter, the TNE is primarily due to the considerable (local) thermodynamic relaxation time. Therefore, the kinetic modeling methods for the two kinds of TNE flows are significantly different. Based on the Discrete Boltzmann Modeling (DBM) method, the non-equilibrium characteristics of mass and heat transfers in slip flow are demonstrated and investigated. The method is solidly verified by comparing with analytic solutions and experimental data. In pressure-driven flow, the DBM results are consistent with experimental data for the Knudsen number up to 0.5. It is verified that, in the slip flow regime, the linear constitutive relations with standard viscous or heat conduction coefficients are no longer applicable near the wall. For the Knudsen layer problem, it is interesting to find that a heat flux (viscous stress) component in the velocity (temperature) Knudsen layer approximates a hyperbolic sinusoidal distribution. The findings enrich the insights into the non-equilibrium characteristics of mass and heat transfers at micro-/nano-scales.
Bats host the most virulent—but not the most dangerous—zoonotic viruses
Authors: Guth Sarah , Mollentze Nardus , Renault Katia , Streicker Daniel G. , Visher Elisa , Boots Mike , Brook Cara E.
Published: March 2022

Significance

The clear need to mitigate zoonotic risk has fueled increased viral discovery in specific reservoir host taxa. We show that a combination of viral and reservoir traits can predict zoonotic virus virulence and transmissibility in humans, supporting the hypothesis that bats harbor exceptionally virulent zoonoses. However, pandemic prevention requires thinking beyond zoonotic capacity, virulence, and transmissibility to consider collective “burden” on human health. For this, viral discovery targeting specific reservoirs may be inefficient as death burden correlates with viral, not reservoir, traits, and depends on context-specific epidemiological dynamics across and beyond the human–animal interface. These findings suggest that longitudinal studies of viral dynamics in reservoir and spillover host populations may offer the most effective strategy for mitigating zoonotic risk.
Autoregulation of switching behavior by cellular compartment size
Authors: Jozsa Monika , Donchev Tihol Ivanov , Sepulchre Rodolphe , O’Leary Timothy
Published: March 2022

Significance

Biochemical reactions often occur in small volumes within a cell, restricting the number of molecules to the hundreds or even tens. At this scale, reactions are discrete and stochastic, making reliable signaling difficult. This paper shows that the transition between discrete, stochastic reactions and macroscopic reactions can be exploited to make a self-regulating switch. This constitutes a previously unidentified kind of reaction network that may be present in small structures, such as synapses.
Differential elastic scattering cross-section of spin-polarized electron beams impinging on uranium
Authors: Dapor Maurizio
Published: March 2022

We investigate the effects of spin-polarization on the differential elastic scattering cross-section (DESCS) of electrons impinging on uranium atoms using the relativistic partial wave expansion method. The calculations presented here were obtained using the POLARe code. Changes in the shape of the DESCS of keV electron beams due to the transverse spin-polarization of the beam are demonstrated to be particularly intense for specific angles and relatively low energies of the incident beam. They can be used to establish the polarization degree of a given electron beam by comparing the POLARe theoretical calculations with experimental data.
Electron beam pumped light emitting devices
Authors: Cuesta Sergi , Harikumar Anjali , Monroy Eva
Published: March 2022

Electron beam pumping is a promising technique to fabricate compact and efficient light emitters (lamps or lasers) in those spectral ranges where electrical injection is problematic due to doping, transport or contacting issues. Interest in this technology has increased in recent years, particularly driven by the demand for ultraviolet sources and the difficulties in developing efficient AlGaN devices to cover the spectral range of 220–350 nm. The use of a highly energetic electron beam enables the semiconductor structure to be pumped without the need for doping or contacting. The active volume is defined by the acceleration voltage, which allows the homogeneous excitation of a large active volume. The efficiency of cathodoluminescent lamps can compete and even outperform light emitting diode in the deep ultraviolet window, and lasers can deliver high optical power (up to around 100 W). Here, we analyze the advantages and challenges of this technology platform, and discuss its potential applications.