bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of lateral erosion in the evolution of nondendritic drainage networks to dendricity and the persistence of dynamic networks
Authors: Kwang Jeffrey S. , Langston Abigail L. , Parker Gary 
Published: April 2021

Significance
Most of Earth’s landscapes are dissected by rivers, which are important for providing water, food, and energy resources. From remote imaging, we see that rivers organize themselves into dendritic (tree-like) networks. The shape and organization of river networks determine how and where water and sediment are routed on Earth. To date, models of river network formation, named landscape evolution models, are unable to explain how nondendritic networks evolve into strongly branching systems. Here, we capture this evolution utilizing a model that incorporates how rivers erode in the lateral direction.
Sensitivity to geometric shape regularity in humans and baboons: A putative signature of human singularity
Authors: Sablé-Meyer Mathias , Fagot Joël , Caparos Serge , van Kerkoerle Timo , Amalric Marie , Dehaene Stanislas 
Published: April 2021

SignificanceDetermining the cognitive differences between human and nonhuman primates is a central goal of cognitive neuroscience. We show that intuitions of geometry are present in humans but absent in baboons. A simple intruder task in which subjects must find which of six geometric shapes is different reveals an effect of geometric regularity in all human groups regardless of age, education, and culture, yet this effect is absent in baboons. Models of the ventral visual pathway for object recognition predict baboons’ performance, but a symbolic model is needed to account for human performance. Our results underline the human propensity for symbolic abstraction, even in an elementary shape perception task, and provide a challenge for neural network models of human shape perception.
Decoding allosteric regulation by the acyl carrier protein
Authors: Sztain Terra , Bartholow Thomas G. , Lee D. John , Casalino Lorenzo , Mitchell Andrew , Young Megan A. , Wang Jianing , McCammon J. Andrew , Burkart Michael D. 
Published: April 2021

SignificanceAcyl carrier proteins (ACPs) are involved in primary and secondary metabolic pathways, including the ubiquitous fatty acid biosynthesis, required for all domains of life. This single protein must deliver pathway intermediates to the appropriate enzyme, distinguishing between a myriad of possible intermediate-enzyme combinations. The intermediate is delivered to the active site of enzymes through a large conformational change termed “chain flipping.” Whether chain flipping is a stochastic or regulated process has remained a mystery. This study provides evidence for an allosteric regulatory mechanism—demonstrating that substrates sequestered within the interior side of the four-helical ACP bundle confer structural changes to the exterior which are recognized by enzymes via protein–protein interactions—presenting a unique paradigm for understanding these biosynthetic pathways.
Distribution of eight heavy metals in the inner shelf sediments of East China Sea: Risk assessments and sources analysis
Authors: Wang Chunjie , Wang Zhangwei , Zhang Xiaoshan 
Published: April 2021

ABSTRACT

Although numerous studies on heavy metals (HMs) in sediments have been carried out in the East China Sea (ECS), the knowledge on the recent pollution levels of HMs in coastal region remains not well understood due to the rapid developments of urbanization in eastern China. In this study, 23 surface samples and 4 core samples are collected in the inner shelf of the ECS. The average dry-weight concentrations follow the descending order of Zn, Cr, Ni, Pb, Cu, As, Cd, and Hg (103.6 ± 26.0, 42.8 ± 12.4, 37.0 ± 9.1, 34.7 ± 11.1, 19.5 ± 10.3, 15.7 ± 11.6, 0.056 ± 0.017, and 0.041 ± 0.017 μg g
−1
, respectively). HMs concentrations share a similar spatial distribution pattern of TOC content with a decreasing trend from coastline to outer sea. Additionally, HMs concentrations exhibit a decreasing trend from top to bottom sediments, especially for Hg at the open sites due to the wet and dry deposition of atmospheric Hg besides the riverine inputs. The potential ecological risk indices (
PERI
) values in coastal sediments were about 2–4 times higher than those in open sea. Although the Hg and Cd concentrations were lower by 2–3 orders of magnitude than those of other six metals, the
PERI
values of Hg (65.5) and Cd (52.1) were 3–40 times higher than those of others. The hierarchical cluster result is consistent with the PCA result, suggesting that Hg, Cd, and As have similar sources and probably mainly originated from anthropogenic emissions.
Moral Orders of Multinationals: Registers of Value in Corporate Food Production
Authors: Yount-André Chelsie 
Published: April 2021

AbstractThis article analyzes moral registers about and within one of the world’s largest food corporations. Based on fieldwork at a French multinational corporation, I trace how speech registers surrounding food circulate across institutional arenas, reconfiguring material connections between the company and consumers. I examine the emergence of a “Big Food” register, critical of the food industry, and analyze the discourses it has triggered within one corporation, comparing talk of ethics and economics among employees in Paris and Johannesburg. Corporate efforts to produce value through food result from struggles between value projects of diverse employees who are positioned differently relative to corporate hierarchies and global inequalities. I argue that moral language in and around the food industry can elucidate current transformations in global capitalism, revealing multinationals’ struggles to credibly voice registers aligned with consumers’ values in their search for competitive advantage.
Opportunities and challenges of inorganic perovskites in high-performance photodetectors
Authors: Cai Wensi , Li Haiyun , Li Mengchao , Wang Meng , Wang Huaxin , Chen Jiangzhao , Zang Zhigang 
Published: April 2021

Abstract
Compared with organic–inorganic hybrid perovskites, fully inorganic perovskites show an increased stability and are therefore attracting considerable attention, especially in recent years. Such materials are not only being extensively used in applications such as solar cells and light-emitting diodes, but also show great potential as photodetectors due to their exceptional optoelectronic properties. In this review, the recent progress on emerging photodetectors based on inorganic perovskites is comprehensively summarized, focusing on the versatile compositions and morphologies of constituent materials and diverse device architectures, and covering the sensing regions from UV–visible–NIR to x-ray and even gamma-ray. A brief outlook that highlights the current challenges impeding the commercialization of inorganic perovskite-based photodetectors is also included, and possible solutions to these problems are provided.
Low-noise, high-detectivity, polarization-sensitive, room-temperature infrared photodetectors based on Ge quantum dot-decorated Si-on-insulator nanowire field-effect transistors
Authors: John John Wellington , Dhyani Veerendra , Singh Sudarshan , Jakhar Alka , Sarkar Arijit , Das Samaresh , Ray Samit K 
Published: April 2021

Abstract
A CMOS-compatible infrared (IR; 1200–1700 nm) detector based on Ge quantum dots (QDs) decorated on a single Si-nanowire channel on a silicon-on-insulator (SOI) platform with a superior detectivity at room temperature is presented. The spectral response of a single nanowire device measured in a back-gated field-effect transistor geometry displays a very high value of peak detectivity ∼9.33 × 1011 Jones at ∼1500 nm with a relatively low dark current (∼20 pA), which is attributed to the fully depleted Si nanowire channel on SOI substrates. The noise power spectrum of the devices exhibits a

1
/

f

γ

,

with the exponent, γ showing two different values of 0.9 and 1.8 owing to mobility fluctuations and generation-recombination of carriers, respectively. Ge QD-decorated nanowire devices exhibit a novel polarization anisotropy with a remarkably high photoconductive gain of ∼104. The superior performance of a Ge QDs/Si nanowire phototransistor in IR wavelengths is potentially attractive to integrate electro-optical devices into Si for on-chip optical communications.
High mobility field-effect transistors based on MoS2 crystals grown by the flux method
Authors: Patil Vilas , Kim Jihyun , Agrawal Khushabu , Park Tuson , Yi Junsin , Aoki Nobuyuki , Watanabe Kenji , Taniguchi Takashi , Kim Gil-Ho 
Published: April 2021

Abstract
Two-dimensional (2D) molybdenum disulphide (MoS2) transition metal dichalcogenides (TMDs) have great potential for use in optical and electronic device applications; however, the performance of MoS2 is limited by its crystal quality, which serves as a measure of the defects and grain boundaries in the grown material. Therefore, the high-quality growth of MoS2 crystals continues to be a critical issue. In this context, we propose the formation of high-quality MoS2 crystals via the flux method. The resulting electrical properties demonstrate the significant impact of crystal morphology on the performance of MoS2 field-effect transistors. MoS2 made with a relatively higher concentration of sulphur (a molar ratio of 2.2) and at a cooling rate of 2.5 °C h−1 yielded good quality and optimally sized crystals. The room-temperature and low-temperature (77 K) electrical transport properties of MoS2 field-effect transistors (FETs) were studied in detail, with and without the use of a hexagonal boron nitride (h-BN) dielectric to address the mobility degradation issue due to scattering at the SiO2/2D material interface. A maximum field-effect mobility of 113 cm2 V−1 s−1 was achieved at 77 K for the MoS2/h-BN FET following high-quality crystal formation by the flux method. Our results confirm the achievement of large-scale high-quality crystal growth with reduced defect density using the flux method and are key to achieving higher mobility in MoS2 FET devices in parallel with commercially accessible MoS2 crystals.
A comparison of insertion methods for surgical placement of penetrating neural interfaces
Authors: Thielen Brianna , Meng Ellis 
Published: April 2021

Abstract
Many implantable electrode arrays exist for the purpose of stimulating or recording electrical activity in brain, spinal, or peripheral nerve tissue, however most of these devices are constructed from materials that are mechanically rigid. A growing body of evidence suggests that the chronic presence of these rigid probes in the neural tissue causes a significant immune response and glial encapsulation of the probes, which in turn leads to gradual increase in distance between the electrodes and surrounding neurons. In recording electrodes, the consequence is the loss of signal quality and, therefore, the inability to collect electrophysiological recordings long term. In stimulation electrodes, higher current injection is required to achieve a comparable response which can lead to tissue and electrode damage. To minimize the impact of the immune response, flexible neural probes constructed with softer materials have been developed. These flexible probes, however, are often not strong enough to be inserted on their own into the tissue, and instead fail via mechanical buckling of the shank under the force of insertion. Several strategies have been developed to allow the insertion of flexible probes while minimizing tissue damage. It is critical to keep these strategies in mind during probe design in order to ensure successful surgical placement. In this review, existing insertion strategies will be presented and evaluated with respect to surgical difficulty, immune response, ability to reach the target tissue, and overall limitations of the technique. Overall, the majority of these insertion techniques have only been evaluated for the insertion of a single probe and do not quantify the accuracy of probe placement. More work needs to be performed to evaluate and optimize insertion methods for accurate placement of devices and for devices with multiple probes.
Superior thermoelectric performance of α-Se2Te monolayer
Authors: Zhong Xuanhong , Huang Yuhong , Yang Xiaoyue , Chen Hong 
Published: April 2021

Abstract
Based on the first-principles of density functional theory and Boltzmann transport theory, we report two-dimensional (2D) α-Se2Te monolayer to be a high-performance medium temperature p-type thermoelectric material with low lattice thermal conductivity (κ

l
), high power factor (PF) and high dimensionless figure of merit (ZT). At the temperature of 700 K, PF is up to 3.77 and 11.5 mW m−1 K−2, ZT is up to 0.55 and 1.91 in appropriate doping level for n- and p-types, respectively, and k

l
is as low as 2.09 W m−1 K−1. We also examine the effect of spin-orbital coupling (SOC) on the carrier transport and find that with SOC, PF and hence ZT will be reduced significantly due to the reduced band gap. The higher PF of p-type than that of n-type is evidently due to the flatter valence band edge than conduction band edge. Low k

l
is inevitably attributed to the strong lattice anharmonicity.
Impact of V substitution on the physical properties of Ni–Zn–Co ferrites: structural, magnetic, dielectric and electrical properties
Authors: Hossain M D , Jamil A T M K , Hasan M R , Ali M A , Esha I N , Hossain Md Sarowar , Hakim M A , Khan M N I 
Published: April 2021

Abstract
We have investigated the Vanadium- (V) substituted Ni–Zn–Co ferrites where the samples are prepared using the solid-state reaction technique. The impact of V5+ substitution on the structural, magnetic, dielectric and electrical properties of Ni–Zn–Co ferrites has been studied. The XRD analysis confirms the formation of a single-phase cubic spinel structure. The lattice constants have been calculated both theoretically and experimentally along with other structural parameters such as bulk density, x-ray density and porosity. The FESEM images are studied for analyzing the surface morphology. FTIR measurement confirms spinel structure formation. The saturation magnetization (M
s), coercive field (H
c) and Bohr magnet on (μ
B) are calculated from the obtained M-H loops. The temperature-dependent permeability is studied to obtain the Curie temperature. The frequency and the composition dependence of permeability are also analyzed. Frequency dependent dielectric behavior and ac resistivity are also investigated. An inverse relationship is observed between the composition dependent dielectric constant and ac resistivity. The obtained results such as the electrical resistivity, dielectric constants and magnetic properties suggest the appropriateness of the studied ferrites in microwave device applications.
Graphitization of carbon-based catalyst for improving the performance of negative electrode in vanadium redox flow battery
Authors: Hou Bingxue , Tang Rui , Zhang Qi , Cui Xumei , Chen Yungui 
Published: April 2021

Abstract
Carbon-based materials were prepared to catalyze the V3+/V2+ couple of vanadium redox flow battery using chitosan as the preliminary material and FeCl3 as activating agent. Graphite microcrystals were the main structures of the obtained catalyst (CTS-Fe-900) activated by FeCl3, and they contained a large number of curled and overlapped carbon nanosheets. Compared with CTS-D-900 (without FeCl3 as an activating agent), CTS-Fe-900 exhibits a better structure, higher graphitization degree, stronger current response, and smaller charge transfer resistance. The charge/discharge measurements indicates that the performances of the cell are improved by using the CTS-Fe-900-modified negative electrode in terms of increased discharge capacity and energy efficiency. Compared with pristine cell, the capacity retention for the CTS-Fe-900 modified cell maintains 82.2% at 50 mA cm−2 after 50 cycles, increased by 5.2%, and the corresponding energy efficiency reaches 81.3%, enhanced by 5.1%. This work reveals that CTS-Fe-900 catalyst can improve the comprehensive energy storage performance. The excellent electrocatalytic properties are mainly attribute to the effect of the FeCl3 template and the increase in the degree of graphitization.
Hydrophobic and optical properties of silica antireflective coating prepared via sol-gel method
Authors: Zhang Qianying , Liu Hui , Zhao Siyuan , Dong Wanmeng 
Published: April 2021

Abstract
A simple and low-cost process for the preparing of multifunctional coating is essential in practical applications. Here, alkali-catalyzed SiO2 antireflection coating was first prepared by using the sol-gel method, the tetraethyl orthosilicate (TEOS) and ammonia (NH3·H2O) were used as a raw material and catalyst, respectively. Then, a layer of dimethyl silicone was sprayed on the surface of the as-prepared primary coating to obtain a bifunctional coating of antireflection and hydrophobicity simultaneously. The experimental results shown that the peak transmittance of the as-prepared bifunctional coating was 98.11% in the wavelength range of 300–1500 nm, while the water contact angle of the prepared coating was 140°, which was caused by the introduction of hydrophobic methyl groups of dimethyl silicone. Besides, the tape adhesion test and pencil scratch test results shown that the coatings have excellent mechanical robustness. Therefore, this work provides a practical strategy for the preparation of bifunctional coatings with antireflective and hydrophobic properties.
Electrochemical detection of choline at f-MWCNT/Fe3O4nanocomposite modified glassy carbon electrode
Authors: Uwaya Gloria E , Fayemi Omolola E 
Published: April 2021

AbstractCholine is employed as cholinergic activity marker in brain tissue in the field of clinical detection of diseases. Although, chromatographic methods and biosensors are the most commonly used techniques for choline detection, there is also an interest in exploring the efficacy of a cost effective non-enzyme based sensor for choline detection. Here, electrochemical sensors based on green synthesized metal oxides (iron (III) oxide nanoparticles) fromCallistemon viminalisleaves and flowers extract (Fe3O4NPL and Fe3O4NPF) in combination of functionalized multi-walled carbon nanotube (f-MWCNT) supported on glassy carbon electrodes (GCE/f-MWCNT/Fe3O4NPL and GCE/f-MWCNT/Fe3O4NPF) were fabricated for choline detection. Morphological, structural and optical analysis of the nanocomposites were studied using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD) and ultra violet-visible (UV–vis) spectroscopy accordingly. In contrast, electron transport properties on bare glassy carbon electrode (GCE) and nanocomposite modified electrodes (GCE/f-MWCNT/Fe3O4NPL and GCE/f-MWCNT/Fe3O4NPF) was examined through electrochemical characterization using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Electrochemical oxidation of choline was also studied through CV, EIS, square wave voltammetry (SWV) and chronoamperometry (CA). The result proved that f-MWCNT enhanced the reactivity of Fe3O4NP towards choline oxidation with voltammetric limit of detection (0.83 and 0.36μM) for choline at GCE/f-MWCNT/Fe3O4NPL and GCE/f-MWCNT/Fe3O4NPF electrodes respectively. Designed sensors proved selective, reproducible, stable and applicable for real sample sensing in choline dietary supplements.
Optimal calibration of gates in trapped-ion quantum computers
Authors: Maksymov Andrii , Niroula Pradeep , Nam Yunseong 
Published: April 2021

Abstract
To harness the power of quantum computing, it is essential that a quantum computer provide maximal possible fidelity for a quantum circuit. To this end, much work has been done in the context of qubit routing or embedding, i.e., mapping circuit qubits to physical qubits based on gate performance metrics to optimize the fidelity of execution. Here, we take an alternative approach that leverages a unique capability of a trapped-ion quantum computer, i.e., the all-to-all qubit connectivity. We develop a method to determine a fixed number (budget) of quantum gates that, when calibrated, will maximize the fidelity of a batch of input quantum programs. This dynamic allocation of calibration resources on randomly accessible gates, determined using our heuristics, increases, for a wide range of calibration budget, the average fidelity from 70% or lower to 90% or higher for a typical batch of jobs on an 11-qubit device, in which the fidelity of calibrated and uncalibrated gates are taken to be 99% and 90%, respectively. Our heuristics are scalable, more than 2.5 orders of magnitude faster than a randomized method for synthetic benchmark circuits generated based on real-world use cases.
Recent progress in 2D metal-organic framework photocatalysts: synthesis, photocatalytic mechanism and applications
Authors: Pan Yangdan , Abazari Reza , Yao Juming , Gao Junkuo 
Published: April 2021

Abstract
2D metal-organic framework (2D MOF) nanosheets and their derived nanocomposites have been widely studied in recent years due to their ultrathin atomic-level thickness, large surface area and adjustable structure. This review is thus aimed at summarizing the recent studies on synthesis methods and the photocatalytic mechanism of 2D MOF nanosheets. The synthesis methods can be concretely divided into top-down and bottom-up methods, including physical and chemical exfoliation, interfacial synthesis, three-layer synthesis and surfactant-assisted synthesis. The photocatalytic mechanisms can also be categorized into three classes: photo-absorption, photo-generated carrier separation and transport, and surface redox reaction. Moreover, the applications of 2D MOF nanosheets in the field of photocatalysis, including photocatalytic hydrogen evolution, photocatalytic CO2 reduction, photocatalytic degradation and organic chemical photosynthesis, were also briefly discussed. Finally, some challenges and expectations with regard to 2D MOF nanosheets in photocatalysis will be addressed.
Peering into few-layer black phosphorus nanosheets: from preparation to battery applications
Authors: Shao Lianyi , Guan Jieduo , Wang Shige , Yu Lu , Shi Xiaoyan , Sun Zhipeng , Cheng Fangyi 
Published: April 2021

Abstract
Few-layer black phosphorus (FLBP) nanosheets feature high charge storage capacity, large surface area, considerable mechanical flexibility, high carrier mobility and adjustable intrinsic band gap, allowing wide applications in electrochemical storage and conversion. This article presents a review on the preparation of FLBP materials and their applications in rechargeable batteries, including alkali metal batteries. Top-down and bottom-up synthetic strategies of FLBP are overviewed with examples of mechanical, liquid-phase and electrochemical exfoliation routes and chemical vapour and pulsed laser deposition. The electrochemical properties, structure-performance relationship and electrode mechanisms of FLBP are demonstrated as anode materials for storage of lithium, sodium and potassium ions. Issues including huge volume expansion and structural instability are discussed, along with solving strategies such as composing with nanostructured carbon, MXene, conductive polymer and transition metal oxides. Furthermore, the remaining challenges and future perspectives for the electrochemical use of FLBP are highlighted.