bluuebunny/crossref_metadata_2025_split huggingface dataset:
Natural selection maintains species despite frequent hybridization in the desert shrubEncelia
Authors: DiVittorio Christopher T. , Singhal Sonal , Roddy Adam B. , Zapata Felipe , Ackerly David D. , Baldwin Bruce G. , Brodersen Craig R. , Búrquez Alberto , Fine Paul V. A. , Padilla Flores Mayra , Solis Elizabeth , Morales-Villavicencio Jaime , Morales-Arce David , Kyhos Donald W. 
Published: December 2020

SignificanceIn Baja California, the deserts meet the coastal dunes in a narrow transition visible even from satellite images. We study two species pairs of desert shrubs (Encelia) that occur across this transition. Although these species can interbreed, they remain distinct. Using a combination of genetics, field experiments, three-dimensional imaging, and physiological measurements, we show that natural selection helps counteract homogenizing effects of gene exchange. Different habitats of these species create multiple mechanisms of selection—drought, salinity, herbivory, and burial, which together maintain these species in their native habitats and their hybrids in intermediate habitats. This study illustrates how environmental factors influence traits and fitness and how these in turn can maintain species, highlighting the importance of natural selection in speciation.
Transcriptional readout of neuronal activity via an engineered Ca
2+
-activated protease
Authors: Sanchez Mateo I. , Nguyen Quynh-Anh , Wang Wenjing , Soltesz Ivan , Ting Alice Y. 
Published: December 2020

Significance
Molecular reporters that “remember” the activity history of a cell and give a corresponding signal that can be read out by imaging, sequencing, or other modalities are valuable tools for the study of neural networks. Here, we develop a reporter that drives stable expression of any transgene (such as a fluorescent protein) in response to cellular calcium activity during a user-defined time window. As calcium is a universal proxy for neural activity, our reporter provides a stable “snapshot” of neural activity which can be used for subsequent imaging, analysis, or manipulation of behavior-associated neural networks. A core feature of our reporter is an engineered calcium-activated protease, which cuts a protein sequence to reveal a transcription factor when cellular calcium levels rise.
Pyridoxal kinase inhibition by artemisinins down-regulates inhibitory neurotransmission
Authors: Kasaragod Vikram Babu , Pacios-Michelena Anabel , Schaefer Natascha , Zheng Fang , Bader Nicole , Alzheimer Christian , Villmann Carmen , Schindelin Hermann 
Published: December 2020

Significance
Information processing in the central nervous system relies on chemical synapses where neurotransmitters such as the inhibitory neurotransmitter γ-aminobutyric acid (GABA) are released at presynaptic nerve endings. GABA is synthesized by glutamic acid decarboxylase (GAD), an enzyme requiring pyridoxal 5'-phosphate (PLP or vitamin B6) as cofactor, the latter being synthesized by pyridoxal kinase (PDXK). Here, we show that the antimalarial drug artemisinin inhibits PDXK and describe the structural basis of this inhibition. The decrease in PLP production reduces the amount of GABA being produced, which, in turn, impacts the efficacy of GABAergic transmission. This study combined with our previous data sheds light on how artemisinins can influence inhibitory synaptic transmissions both presynaptically, as described here, and postsynaptically.
Low potential for evolutionary rescue from climate change in a tropical fish
Authors: Morgan Rachael , Finnøen Mette H. , Jensen Henrik , Pélabon Christophe , Jutfelt Fredrik 
Published: December 2020

Significance
There is currently great concern about the ability of organisms to adapt to warmer environments. During heat waves, upper thermal tolerance is often critical for survival, but it is largely unknown how rapidly tolerance can evolve, especially in vertebrates. We artificially selected on upper thermal tolerance in a tropical fish to see whether and how quickly thermal tolerance evolves, and how warm acclimation prior to a thermal challenge alters this evolutionary process. Upper thermal tolerance evolved but at a slow rate toward higher temperature. Furthermore, acclimation capacity decreased in the lines selected for higher thermal tolerance. These results suggest that tropical fishes will struggle to adapt in pace with the current climate warming.
A modern scleractinian coral with a two-component calcite–aragonite skeleton
Authors: Stolarski Jarosław , Coronado Ismael , Murphy Jack G. , Kitahara Marcelo V. , Janiszewska Katarzyna , Mazur Maciej , Gothmann Anne M. , Bouvier Anne-Sophie , Marin-Carbonne Johanna , Taylor Michelle L. , Quattrini Andrea M. , McFadden Catherine S. , Higgins John A. , Robinson Laura F. , Meibom Anders 
Published: December 2020

SignificanceUntil now, all of the ca. 1,800 known modern scleractinian coral species were thought to produce skeletons exclusively of aragonite. AsymbioticParaconotrochus antarcticusliving in the Southern Ocean is the first example of an extant scleractinian that forms a two-component carbonate skeleton, with an inner structure made of high-Mg calcite and an outer structure composed of aragonite. This discovery adds support to the notion that the coral skeletal formation process is strongly biologically controlled. Mitophylogenomic analysis shows thatP.antarcticusrepresents an ancient scleractinian clade, suggesting that skeletal mineralogy/polymorph of a taxon, once established, is a trait conserved throughout the evolution of that clade.
Archaeological Central American maize genomes suggest ancient gene flow from South America
Authors: Kistler Logan , Thakar Heather B. , VanDerwarker Amber M. , Domic Alejandra , Bergström Anders , George Richard J. , Harper Thomas K. , Allaby Robin G. , Hirth Kenneth , Kennett Douglas J. 
Published: December 2020

SignificanceMaize is a global food staple with great economic and cultural importance. Archaeogenomic studies have revealed a process of protracted maize domestication and multiple waves of human-mediated dispersal in the Americas. Maize first arrived in South America as a partial domesticate, where the domestication syndrome became independently fixed and improved varieties developed away from the influence of wild gene flow. We demonstrate that hybrids of some of these improved varieties were likely reintroduced back to Central America. We hypothesize that this backflow of South American genetic material may have contributed to the development of a more productive staple, which was related to the growth and aggregation of human populations, and the formation of more complex social and political structures regionally.
Plant stem-cell organization and differentiation at single-cell resolution
Authors: Satterlee James W. , Strable Josh , Scanlon Michael J. 
Published: December 2020

Significance
Plants possess the remarkable ability to grow and produce new organs throughout their lifespan, owing to the activities of persistent populations of pluripotent stem cells within their meristematic tips. Here we isolated individual cells from the microscopic shoot apical meristem (SAM) of maize and provide single-cell transcriptomic analysis of a plant shoot meristem. This study enabled an unbiased analysis of the developmental genetic organization of the maize shoot apex and uncovered evolutionarily divergent and conserved signatures of SAM homeostasis. The fine-scale resolution of single-cell analysis was used to reconstruct the process of shoot cell differentiation, whereby stem cells acquire diverse and distinct cell fates over developmental time in wild-type and mutant maize seedlings.
Exchange bias in BiFeO3 and Bi0.9La0.1FeO3 nanoparticles
Authors: Vivek S , Kumar Ajith S , Chitra Lekha C S , Nair Swapna S 
Published: December 2020

Abstract
The exchange bias (EB) effects of BiFeO3 (BFO) and Bi0.9La0.1FeO3 nanopowders are investigated. An EB field of 152 Oe and 902 Oe at 60 K are observed for BFO and Bi0.9La0.1FeO3, respectively, when cooled in 20 kOe magnetic field. The enhancement of EB values in the case of Bi0.9La0.1FeO3 is explained based on the combination of Malozemoff’s and domain state models. Training effect measurements data fitted with Binek’s model suggested that the origin of EB lies in the interaction between the antiferromagnetic (AFM) core and the soft magnetic shell. Memory effect measurements, thermoremanent and isoremanent magnetization studies, and time decay of thermoremanent magnetization studies are done to understand the nature of the shell of both the samples. Time decay of thermoremanent magnetization of BFO is fitted with a stretched exponential based on Kohlrausch–Williams–Watt model, the obtained shape parameter value lies in the range of Heisenberg type spin-glasses. From thermoremanent and isoremanent magnetization plots, a 2D-diluted AFM shell is observed for Bi0.9La0.1FeO3. The field cooling and the temperature dependence of EB are investigated and the results are explained based on the available models of EB.
Super-Arrhenius diffusion in a binary colloidal mixture at low volume fraction: an effect of depletion interaction due to an asymmetric barrier
Authors: Singh Jalim , Mustakim Mahammad , Anil Kumar A V 
Published: December 2020

Abstract
We report results from the molecular dynamics simulations of a binary colloidal mixture subjected to an external potential barrier along one of the spatial directions at low volume fraction, ϕ = 0.2. The variations in the asymmetry of the external potential barrier do not change the dynamics of the smaller particles, showing Arrhenius diffusion. However, the dynamics of the larger particles shows a crossover from sub-Arrhenius to super-Arrhenius diffusion with the asymmetry in the external potential at the low temperatures and low volume fraction. Super-Arrhenius diffusion is generally observed in the high density systems where the transient cages are present due to dense packing, e.g., supercooled liquids, jammed systems, diffusion through porous membranes, dynamics within the cellular environment, etc. This model can be applied to study the molecular transport across cell membranes, nano-, and micro-channels which are characterized by spatially asymmetric potentials.
Calibration method for the rotating axis in panoramic 3D shape measurement based on a turntable
Authors: Cai Xiaoqi , Zhong Kejun , Fu Yanjun , Chen Jianbin , Liu Yanzhao , Huang Chunzhi 
Published: December 2020

Abstract
In panoramic three-dimensional (3D) shape measurement based on a turntable, the point cloud registration accuracy is greatly affected by the calibration of the rotating axis. To improve the calibration accuracy of the rotating axis, a calibration method based on an auxiliary camera is proposed. The calibration procedure uses a checkerboard and an auxiliary camera. Firstly, the checkerboard is rotated on the turntable to determine the rotation axis, and is used to calibrate the relative orientation of the auxiliary camera and the measurement camera, so that the two cameras have the same world coordinate system. Then, the origin point of the coordinate of the rotation axis is obtained by the auxiliary camera, and the Z-axis direction is taken as the direction of the rotation axis. Finally, the 3D shape of the multi-view is measured by the fringe projection system, and the rotation registration is completed according to the rotation axis vector. The proposed method does not need to reconstruct the 3D coordinates of multiple points when the rotating axis is calibrated. The experimental results show that the proposed method effectively improves the calibration accuracy of the rotation axis vector, and reduces the complexity of the calibration process.
Characterisation of a multi-view fringe projection system based on the stereo matching of rectified phase maps
Authors: Shaheen A , Sims-Waterhouse D , Bointon P , Takushima S , Piano S , Leach R K 
Published: December 2020

Abstract
Multi-view fringe projection systems can be effective solutions to address the limitations imposed by the limited field of view, line-of-sight issues and occlusions when measuring the geometry of complex objects, associated with single camera–projector systems. However, characterisation of a multi-view system is challenging since it requires the cameras and projectors to be in a common global coordinate system. We present a method for characterising a multi-view fringe projection system which does not require the characterisation of the projector. The novelty of the method lies in determining the correspondences in the phase domain using the rectified unwrapped phase maps and triangulating the matched phase values to reconstruct the three-dimensional shape of the object. A benefit of the method is that it does not require registration of the point clouds acquired from multiple perspectives. The proposed method is validated by experiment and comparison with a conventional system and a contact coordinate measuring machine.
Time dependence of negative and positive photoconductivity for Si δ-doped AlGaAs/InGaAs/AlGaAs quantum well under various temperatures and various incident photon energies and intensities
Authors: Su Wilson Yeung-Sy , Wang Ching , Chen Chih-Ting , Huang Bu-Wei , Li Chun-Yi , Wu Chii-Bin , Wang Jyh-Shyang , Shen Ji-Lin , Chiu Kuan-Cheng 
Published: December 2020

Abstract
Si δ-doped AlGaAs/InGaAs/AlGaAs quantum well (QW) structure is commonly adopted as one of the core elements in modern electric and optoelectronic devices. Here, the time dependent photoconductivity spectra along the active InGaAs QW channel in a dual and symmetric Si δ-doped AlGaAs/InGaAs/AlGaAs QW structure are systematically studied under various temperatures (T = 80–300 K) and various incident photon energies (E

in
= 1.10–1.88 eV) and intensities. In addition to positive photoconductivity, negative photoconductivity (NPC) was observed and attributed to two origins. For T = 180–240 K with E

in
= 1.51–1.61 eV, the trapping of the photo-excited electrons by the interface states located inside the conduction band of InGaAs QW layer is one of the origins for NPC curves. For T = 80–120 K with E

in
= 1.10–1.63 eV, the photoexcitation of the excess ‘supersaturated’ electrons within the active InGaAs QW caused by the short cooling process is another origin.
Strain-inducing photochemical chlorination of graphene nanoribbons on SiC (0001)
Authors: Copetti Gabriela , Nunes Eduardo H , Feijó Taís O , Galves Lauren A , Heilmann Martin , Soares Gabriel V , Lopes J Marcelo J , Radtke Cláudio 
Published: December 2020

Abstract
As different low-dimensional materials are sought to be incorporated into microelectronic devices, graphene integration is dependent on the development of band gap opening strategies. Amidst the different methods currently investigated, application of strain and use of electronic quantum confinement have shown promising results. In the present work, epitaxial graphene nanoribbons (GNR), formed by surface graphitization of SiC (0001) on crystalline step edges, were submitted to photochemical chlorination. The incorporation of Cl into the buffer layer underlying graphene increased the compressive uniaxial strain in the ribbons. Such method is a promising tool for tuning the band gap of GNRs.
TALIF measurements of hydrogen and deuterium surface loss probabilities on quartz in low pressure high density plasmas
Authors: Yang X , Kogut D , Couëdel L , Angot T , Roubin P , Faure J-B , Cartry G 
Published: December 2020

Abstract
This article deals with surface loss on quartz of atomic hydrogen (H) and its isotope deuterium (D) in a low-pressure (10 Pa) pulsed inductively coupled plasma. The atomic temporal decay in the post discharge is measured by two-photon absorption laser-induced fluorescence (TALIF). From the loss rate, the atomic surface loss probability is determined. In pure hydrogen or pure deuterium gas, no isotopic effect on surface kinetics has been observed and the surface loss probabilities of H and D were found to be almost identical and equal to ∼1.8%. However, despite the lack of difference in surface loss probability, a net isotopic effect on surface loss rate due to the mass difference between the isotopes is measured. Hydrogen atoms diffuse faster and have higher flux to the plasma chamber walls than deuterium atoms. Hydrogen atoms are therefore lost at higher rate than deuterium atoms. Based on the observed isotopic difference and on the comparison between H and D TALIF signals, the isotopic effects on H and D atom production are discussed.
Effects of sequential annealing in low oxygen partial-pressure and NO on 4H-SiC MOS devices
Authors: Luo Zhipeng , Wan Caiping , Jin Zhi , Xu Hengyu 
Published: December 2020

Abstract
The effects of low oxygen partial pressure (low-pO2) annealing and NO annealing on both performance and reliability of silicon carbide (SiC) MOS capacitors are verified, and the sequential annealing in low-pO2 and NO is also investigated. The sequential annealing is effective to improve the reliability of SiC MOS capacitors but shows slight deterioration of interface property. The results show that annealing in the atmosphere of low partial pressure oxygen changes the distribution of defect about the SiO2/SiC interface, and influences the following NO annealing effect. The mechanism of oxidation and annealing is discussed, and some suggestions on annealing are given. This experiment provides some inspiration for the combination of annealing processes and the optimization of annealing conditions.
Optimal tuning of SMA inerter for simultaneous wind induced vibration control of high-rise building and energy harvesting
Authors: Das Sourav , Chakraborty Arunasis , Barua Ipshita 
Published: December 2020

Abstract
This study proposes shape memory alloy based inerter combined with electromagnetic transducer for both vibration control of buildings and energy harvesting. The proposed device has non-linear spring made of shape memory alloy for its excellent load-deformation characteristics. The hysteretic behavior of this smart material is capable of dissipating significant amount of energy. The conventional viscous damping is also replaced by a motor, which offers flexibility in damping while converting the mechanical energy into power. The optimal performance of this device demands precise tuning of its parameters for vibration control of the building, which is exposed to random wind load. This, in turn, advocates for the solution of stochastic non-linear optimization problem, which is the main aim of this study. It is proposed in two steps i.e. adopt equivalent linearization for efficient input–output characterization followed by an ensemble surrogate analysis for stochastic response quantification. A seventy six storied benchmark building is used for numerical demonstration, which clearly establishes the superiority of the passive device for simultaneous vibration control and energy harvesting over the possible range of wind speeds. The results show that the ensemble surrogate model is very efficient to predict the responses compared to a single surrogate model. Overall the performance of the controller is impressive and can be adopted for further experimental investigation prior to its use in prototype buildings.
Effects of installation position of fin-shaped rods on wind-induced vibration and energy harvesting of aeroelastic energy converter
Authors: Ding Lin , Mao Xiangxi , Yang Lin , Yan Bowen , Wang Junlei , Zhang Li 
Published: December 2020

Abstract
The influence of fin-shaped rod (FSR) with different installation positions on wind-induced vibration and energy harvesting of a cylinder-based aeroelastic energy harvester are studied by experiments and simulations. Two FSRs are installed symmetrically on the surface of a circular cylinder, and the coverage angle of each FSR is 20°. The installation position of FSRs on the cylinder is represented by the placement angle, θ, which varies in the range of ±160°. And the tested wind speed range is 0–6.8 m s−1. The results show that FSRs change the position of the separation point of the boundary shear layers, further affect the formation and shedding of vortices. Then the force on the cylinder changes, which causes the energy harvester to produce different vibration responses and energy outputs. When 0° < θ < 70°, back-to-back vortex-induced vibration (VIV) and galloping can be observed for FSR-cylinder, and the output power increases with the increase of wind speed, the maximum output voltage and power reach 18.1 V and 1.645 mW. For 70° ⩽ θ < 120°, the vibration of FSR-cylinder is suppressed, which is not conducive for energy harvesting. When 120° < θ ⩽ 160°, the vibration of FSR-cylinder firstly experiences VIV and then galloping occurs after reaching the critical wind speed.
A new eccentric resonance matching layer with anti-reflection characteristics for underwater acoustic scattering suppression
Authors: Duan Jinxiu , Li Shande , Wu Xiaoxun , Wang Cun , Ma Yane 
Published: December 2020

Abstract
The narrow frequency bandwidth and the effective frequency which cannot be low enough are two major challenges in underwater acoustics. To overcome these drawbacks, a new eccentric resonance matching layer with anti-reflection characteristics is proposed for underwater acoustic scattering suppression. Homogenization method and anti-reflection theory are applied for the design of anti-reflection structure. The complete mathematical model is developed based on the finite element method (FEM). Numerical simulations are carried out by COMSOL to verify the accuracy of the mathematical model. The results show that the proposed matching layer can significantly improve the broadband absorption capacity and can effectively suppress underwater acoustic scattering, especially at relatively low frequencies. It is a breakthrough in underwater low-frequency acoustic absorption, indicating that the structure has application prospects in underwater acoustic stealth, acoustic energy dissipation and acoustic wave regulation.
Role of film thickness and disorder in tuning perpendicular magnetic anisotropy in GdTb-FeCo alloy films
Authors: Sahoo Ajit Kumar , Chelvane J Arout , Mohanty J 
Published: December 2020

Abstract
GdTb-FeCo based quaternary system of various thicknesses (30, 50, 75, 150, and 300 nm) is explored in pursuit of tuneable perpendicular magnetic anisotropy (PMA). Spin reorientation and strong PMA is evident at higher film thickness. A variety of microscopic domains can be referred to as disorder in domains, have been observed. Gd-like and Tb-like contributing domains are observed in various films. A critical thickness is observed at 150 nm, where most of the Tb-sublattices are dominated over the Gd-sublattices. Magnetic parameters do not follow the trend at 150 nm, which could be attributed to a lesser extent of pinning sites impeded to domain wall motions. The experimental finding is complemented with 3D micromagnetic simulations.