bluuebunny/crossref_metadata_2025_split huggingface dataset:
Charge‐Accumulation Effect in Transition Metal Dichalcogenide Heterobilayers
Authors: Ye Tong , Li Junze , Li Dehui 
Published: August 2019

AbstractCharge transfer in transition‐metal‐dichalcogenides (TMDs) heterostructures is a prerequisite for the formation of interlayer excitons, which hold great promise for optoelectronics and valleytronics. Charge accumulation accompanied by a charge‐transfer process can introduce considerable effect on interlayer exciton‐based applications; nevertheless, this aspect has been rarely studied up to date. This work demonstrates how the charge accumulation affects the light emission of interlayer excitons in van der Waals heterobilayers (HBs) consisting of monolayer WSe2 and WS2. As excitation power increases, the photoluminescence intensity of interlayer excitons increases more rapidly than that of intralayer excitons. The phenomenon can be explained by charge‐accumulation effect, which not only increases the recombination probability of interlayer excitons but also saturates the charge‐transfer process. This scenario is further confirmed by a careful examination of trion binding energy of WS2, which nonlinearly increases with the increase of the excitation power before reaching a maximum of about 75 meV. These investigations provide a better understanding of interlayer excitons and trions in HBs, which may provoke further explorations of excitonic physics as well as TMDs‐based devices.
Atomically Sharp Dual Grain Boundaries in 2D WS2 Bilayers
Authors: Chen Jun , Jung Gang Seob , Ryu Gyeong Hee , Chang Ren‐Jie , Zhou Si , Wen Yi , Buehler Markus J. , Warner Jamie H. 
Published: August 2019

AbstractIt is shown that tilt grain boundaries (GBs) in bilayer 2D crystals of the transition metal dichalcogenide WS2 can be atomically sharp, where top and bottom layer GBs are located within sub‐nanometer distances of each other. This expands the current knowledge of GBs in 2D bilayer crystals, beyond the established large overlapping GB types typically formed in chemical vapor deposition growth, to now include atomically sharp dual bilayer GBs. By using atomic‐resolution annular dark‐field scanning transmission electron microscopy (ADF‐STEM) imaging, different atomic structures in the dual GBs are distinguished considering bilayers with a 3R (AB stacking)/2H (AA′ stacking) interface as well as bilayers with 2H/2H boundaries. An in situ heating holder is used in ADF‐STEM and the GBs are stable to at least 800 °C, with negligible thermally induced reconstructions observed. Normal dislocation cores are seen in one WS2 layer, but the second WS2 layer has different dislocation structures not seen in freestanding monolayers, which have metal‐rich clusters to accommodate the stacking mismatch of the 2H:3R interface. These results reveal the competition between maintaining van der Waals bilayer stacking uniformity and dislocation cores required to stitch tilted bilayer GBs together.
WSe2 Homojunction Devices: Electrostatically Configurable as Diodes, MOSFETs, and Tunnel FETs for Reconfigurable Computing
Authors: Pang Chin‐Sheng , Chen Chin‐Yi , Ameen Tarek , Zhang Shengjiao , Ilatikhameneh Hesameddin , Rahman Rajib , Klimeck Gerhard , Chen Zhihong 
Published: August 2019

AbstractIn this paper, electrostatically configurable 2D tungsten diselenide (WSe2) electronic devices are demonstrated. Utilizing a novel triple‐gate design, a WSe2 device is able to operate as a tunneling field‐effect transistor (TFET), a metal–oxide–semiconductor field‐effect transistor (MOSFET) as well as a diode, by electrostatically tuning the channel doping to the desired profile. The implementation of scaled gate dielectric and gate electrode spacing enables higher band‐to‐band tunneling transmission with the best observed subthreshold swing (SS) among all reported homojunction TFETs on 2D materials. Self‐consistent full‐band atomistic quantum transport simulations quantitatively agree with electrical measurements of both the MOSFET and TFET and suggest that scaling gate oxide below 3 nm is necessary to achieve sub‐60 mV dec−1 SS, while further improvement can be obtained by optimizing the spacers. Diode operation is also demonstrated with the best ideality factor of 1.5, owing to the enhanced electrostatic control compared to previous reports. This research sheds light on the potential of utilizing electrostatic doping scheme for low‐power electronics and opens a path toward novel designs of field programmable mixed analog/digital circuitry for reconfigurable computing.
Tumor pH‐Responsive Albumin/Polyaniline Assemblies for Amplified Photoacoustic Imaging and Augmented Photothermal Therapy
Authors: Tian Qiwei , Li Yaping , Jiang Shanshan , An Lu , Lin Jiaomin , Wu Huixia , Huang Peng , Yang Shiping 
Published: August 2019

AbstractTumor‐microenvironment‐responsive theranostics have great potential for precision diagnosis and effective treatment of cancer. Polyaniline (PANI) is the first reported pH‐responsive organic photothermal agent and is widely used as a theranostic agent. However, tumor pH‐responsive PANI‐based theranostic agents are not explored, mainly because the conversion from the emeraldine base (EB) to emeraldine salt (ES) state of PANI requires pH < 4, which is lower than tumor acidic microenvironment. Herein, a tumor pH‐responsive PANI‐based theranostic agent is designed and prepared for amplified photoacoustic imaging guided augmented photothermal therapy (PTT), through intermolecular acid–base reactions between carboxyl groups of bovine serum albumin (BSA) and imine moieties of PANI. The albumin/PANI assemblies (BSA–PANI) can convert from the EB to ES state at pH < 7, accompanied by the absorbance redshift from visible to near‐infrared region. Both in vitro and in vivo results demonstrate that tumor acidic microenvironment can trigger both the photoacoustic imaging (PAI) signal amplification and the PTT efficacy enhancement of BSA–PANI assemblies. This work not only highlights that BSA–PANI assemblies overcome the limitation of low‐pH protonation, but also provides a facile assembly strategy for a tumor pH‐responsive PANI‐based nanoplatform for cancer theranostics.
Controllable Fabrication of Inhomogeneous Microcapsules for Triggered Release by Osmotic Pressure
Authors: Zhang Weixia , Qu Liangliang , Pei Hao , Qin Zhao , Didier Jonathan , Wu Zhengwei , Bobe Frank , Ingber Donald E. , Weitz David A. 
Published: August 2019

AbstractInhomogeneous microcapsules that can encapsulate various cargo for controlled release triggered by osmotic shock are designed and reported. The microcapsules are fabricated using a microfluidic approach and the inhomogeneity of shell thickness in the microcapsules can be controlled by tuning the flow rate ratio of the middle phase to the inner phase. This study demonstrates the swelling of these inhomogeneous microcapsules begins at the thinnest part of shell and eventually leads to rupture at the weak spot with a low osmotic pressure. Systematic studies indicate the rupture fraction of these microcapsules increases with increasing inhomogeneity, while the rupture osmotic pressure decreases linearly with increasing inhomogeneity. The inhomogeneous microcapsules are demonstrated to be impermeable to small probe molecules, which enables long‐term storage. Thus, these microcapsules can be used for long‐term storage of enzymes, which can be controllably released through osmotic shock without impairing their biological activity. The study provides a new approach to design effective carriers to encapsulate biomolecules and release them on‐demand upon applying osmotic shock.
A Novel Approach to High‐Performance Aliovalent‐Substituted Catalysts—2D Bimetallic MOF‐Derived CeCuOx Microsheets
Authors: Wang Qingyue , Li Zhimin , Bañares Miguel A. , Weng Lu‐Tao , Gu Qinfen , Price Jason , Han Wei , Yeung King Lun 
Published: August 2019

AbstractMixed transition metal oxides (MTMOs) have enormous potential applications in energy and environment. Their use as catalysts for the treatment of environmental pollution requires further enhancement in activity and stability. This work presents a new synthesis approach that is both convenient and effective in preparing binary metal oxide catalysts (CeCuOx) with excellent activity by achieving molecular‐level mixing to promote aliovalent substitution. It also allows a single, pure MTMO to be prepared for enhanced stability under reaction by using a bimetallic metal–organic framework (MOF) as the catalyst precursor. This approach also enables the direct manipulation of the shape and form of the MTMO catalyst by controlling the crystallization and growth of the MOF precursor. A 2D CeCuOx catalyst is investigated for the oxidation reactions of methanol, acetone, toluene, and o‐xylene. The catalyst can catalyze the complete reactions of these molecules into CO2 at temperatures below 200 °C, representing a significant improvement in performance. Furthermore, the catalyst can tolerate high moisture content without deactivation.
Construction of a Plasmonic Chip for Metabolic Analysis in Cervical Cancer Screening and Evaluation
Authors: Shu Weikang , Wang You , Liu Chao , Li Rongxin , Pei Congcong , Lou Weihua , Lin Sihan , Di Wen , Wan Jingjing 
Published: August 2019

AbstractThere is a high demand for high‐throughput in vitro metabolic analysis in clinical practice. However, current metabolic analysis of biofluids requires tedious sample pretreatment due to sample complexity and low molecular abundance. Herein, a plasmonic chip with Au nanoparticles deposited on a dopamine‐bubble layer is constructed for clinical metabolic fingerprints. The structural parameters of the designed chip are optimized in terms of surface roughness and Au content. The established chip enables fast, sensitive, and selective detection of small metabolites in human serum without any enrichment or purification. On‐chip serum fingerprints further allow for differentiation between women diagnosed with cervical cancer and control subjects, as well as the therapeutic evaluation for potential clinical monitoring. This work boosts the application of laser desorption/ionization mass spectrometry in large‐scale clinical in vitro diagnosis.
Is It Appropriate to Use the Nafion Membrane in Electrocatalytic N2 Reduction?
Authors: Ren Yongwen , Yu Chang , Tan Xinyi , Han Xiaotong , Huang Hongling , Huang Huawei , Qiu Jieshan 
Published: August 2019

AbstractThe electrocatalytic N2 reduction reaction (ENRR) to ammonia has attracted much attention due to the mild operating conditions, in which the Nafion membrane is generally adopted to separate the ammonia from the anode products. However, it has been mentioned that the Nafion membrane allows ammonia to pass through and traps the ammonia to some extent, but powerful confirmation experiments and effective solutions are still lacking. Herein, it is experimentally confirmed that the use of the Nafion membrane in the ENRR is inappropriate, based on the results that the ammonia can pass through the membrane, be adsorbed on the membrane, and interact with the membrane. This causes a measurement error and accelerates the membrane degradation process, which is unfavorable for ammonia quantification and the long‐term stability operation of the ENRR in practical application. Also, for the first time, a more accurate method to evaluate the activity of the ENRR electrocatalyst using a salt bridge to replace the Nafion membrane is presented.
Robust path‐following control based on trajectory linearization control for unmanned surface vehicle with uncertainty of model and actuator saturation
Authors: Qiu Bingbing , Wang Guofeng , Fan Yunsheng , Mu Dongdong , Sun Xiaojie 
Published: August 2019

AbstractThis article develops a novel path‐following control strategy for underactuated unmanned surface vehicle (USV) subject to unmodeled dynamics and unknown multiple disturbance. A practical robust path‐following controller is proposed using trajectory linearization control (TLC) technology, neural network, and auxiliary design system. First, the greatest advantage of this article is that the TLC technology is first introduced into the field of USV motion control, which provides a new direction for TLC technology research. Second, the underactuated model based on a transformation of the USV kinematics to Serret‐Frenet frame is simplified by introducing a nonlinear coordinate transformation. Meanwhile, to improve the robustness and reduce the computational complexity, radial basis function neural network is replaced by neural network with minimum learning parameter method to compensate for unmodeled dynamics and unknown multiple disturbance. In addition, an auxiliary dynamic system is used to reduce the risk of actuator saturation. The stability of the whole system was proved based on the Lyapunov criteria. Finally, the comparison results demonstrate the superior performance of the proposed approach. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Evaluation of ecological restoration success in mining‐degraded lands
Authors: Bandyopadhyay Sneha , Maiti Subodh Kumar 
Published: August 2019

AbstractThis review article analyzes the importance of assessing the success of ecological restoration by using four indicators: assemblage of the plant and animal communities; enzyme activity; litter accumulation and decomposition; and the improvement of soil quality. These indicators can be used alone or in combinations. Even though the Society for Ecological Restoration International provided a primer containing nine attributes to use as standards for measuring ecological restoration, only three of these attributes could be easily applied due to their low costs and low time requirements. These three attributes include: diversity, vegetation structure, and ecological processes. This review article emphasizes that the criteria for the selection of the indicator species should be based upon: habitat types, abundance of species, ease of measuring, quantifying and interpreting the results, gradual enhancement with time and cost‐effectiveness, sensitivity, variability of response, size, residential status, and requirements of the area. Principal component analysis was applied to calculate the reclaimed mine soil quality index (RMSQI) and the forest soil quality index (FSQI) and the RMSQI value was compared with FSQI (optimum index value of reference ecosystem) to evaluate the restoration success. Available phosphorus, exchangeable magnesium, organic carbon, clay content, field moisture, available nitrogen, electrical conductivity, and pH are identified as the most influential parameters that regulate the health of reclaimed mine soil. Exchangeable calcium, magnesium, cation exchange capacity, sand, silt, clay content, field moisture, available phosphorus, and pH are the controlling properties for forest soil. The observed values of the above‐stated soil indicator properties were converted into a unitless score (0–1.00) and integrated into index calculations (RMSQI and FSQI). The contribution of each soil indicator properties on the calculated index was analyzed, which provides insight into the reason for the measured index. A higher RMSQI indicates better ecological restoration success. The calculated RMSQI was found to be 0.473 in the reclaimed dump, which is 6% lower than the reference ecosystem.
Ethics and social responsibility: A bibliometric study of document production based on Web of Science in the period of 2006 to 2016
Authors: Godoy Taís Pentiado , Martins‐Rodrigues Maria Carolina , da Rosa Luciana Aparecida Barbieri , Damke Luana Inês , Gomes Clandia Maffini 
Published: August 2019

AbstractThe objective of this work is to analyze the production of publications on the theme of ethics and social responsibility from 2006 to 2016 based on the scientific citation indexing service, the Web of Science (WOS), through a descriptive, quantitative, and bibliometric study. This study, which considered 2,610 documents, sought to identify the authors, the types of documents (books, book chapters, journal articles, and conference proceedings), the titles of the sources, the research areas, the year published, institutions with which authors were affiliated, languages in which the documents were published, and the countries of these publications. The greatest number of documents was published in the United States, with the overwhelming majority 93.43% of publications written in the English language. The source of the greatest number of documents was the Journal of Business Ethics, and the main research area was business economics. Researchers also observed that, in the 71 publications with the greatest number of citations referenced in the researched topic, the top three authors were Guido Palazzo, with 1,730 citations, Andreas Georg Scherer, with 1,352 citations, and Jeremy Moon with a total of 1,132 citations.
New polyhedral and algorithmic results on greedoids
Authors: Szeszlér Dávid 
Published: August 2019

AbstractWe present various new results on greedoids. We prove a theorem that generalizes an equivalent formulation of Edmonds’ classic matroid polytope theorem to local forest greedoids—a class of greedoids that contains matroids as well as branching greedoids. We also describe an application of this theorem in the field of measuring the reliability of networks by game-theoretical tools. Finally, we prove new results on the optimality of the greedy algorithm on greedoids and correct some mistakes that have been present in the literature for almost 3 decades.
Localized Induction of Gene Expression in Embryonic Stem Cell Aggregates Using Holographic Optical Tweezers to Create Biochemical Gradients
Authors: Kirkham Glen R , Ware James , Upton Thomas , Allen Stephanie , Shakesheff Kevin M , Buttery Lee DK 
Published: August 2019

AbstractThree-dimensional (3D) cell models that mimic the structure and function of native tissues are enabling more detailed study of physiological and pathological mechanisms in vitro. We have previously demonstrated the ability to build and manipulate 3D multicellular microscopic structures using holographic optical tweezers (HOTs). Here, we show the construction of a precisely patterned 3D microenvironment and biochemical gradient model consisting of mouse embryoid bodies (mEBs) and polymer microparticles loaded with retinoic acid (RA), embedded in a hydrogel. We demonstrate discrete, zonal expression of the RA-inducible protein Stra8 within mEBs in response to release of RA from polymer microparticles, corresponding directly to the defined 3D positioning of the microparticles using HOTs. These results demonstrate the ability of this technology to create chemical microgradients at definable length scales and to elicit, with fidelity and precision, specific biological responses. This technique can be used in the study of in vitro microenvironments to enable new insights on 3D cell models, their cellular assembly, and the delivery of drug or biochemical molecules for engineering and interrogation of functional and morphogenic responses.
Improving Atmospheric River Forecasts With Machine Learning
Authors: Chapman W. E. , Subramanian A. C. , Delle Monache L. , Xie S. P. , Ralph F. M. 
Published: August 2019

AbstractThis study tests the utility of convolutional neural networks as a postprocessing framework for improving the National Center for Environmental Prediction's Global Forecast System's integrated vapor transport forecast field in the Eastern Pacific and western United States. Integrated vapor transport is the characteristic field of atmospheric rivers, which provide over 65% of yearly precipitation at some western U.S. locations. The method reduces full‐field root‐mean‐square error (RMSE) at forecast leads from 3 hr to seven days (9–17% reduction), while increasing correlation between observations and predictions (0.5–12% increase). This represents an approximately one‐ to two‐day lead time improvement in RMSE. Decomposing RMSE shows that random error and conditional biases are predominantly reduced. Systematic error is reduced up to five‐day forecast lead, but accounts for a smaller portion of RMSE. This work demonstrates convolutional neural networks potential to improve forecast skill out to seven days for precipitation events affecting the western United States.
Analysis of the Atmospheric Water Budget for Elucidating the Spatial Scale of Precipitation Changes Under Climate Change
Authors: Dagan Guy , Stier Philip , Watson‐Parris Duncan 
Published: August 2019

AbstractGlobal mean precipitation changes due to climate change were previously shown to be relatively small and well constrained by the energy budget. However, local precipitation changes can be much more significant. In this paper we propose that for large enough scales, for which the water budget is closed (precipitation [P] roughly equals evaporation [E]), changes in P approach the small global mean value. However, for smaller scales, for which P and E are not necessarily equal and convergence of water vapor still plays a role, changes in P could be much larger due to dynamical contributions. Using 40 years of two reanalysis data sets, 39 Coupled Model Intercomparison Project Phase 5 (CMIP5) models and additional numerical simulations, we identify the scale of transition in the importance of the different terms in the water budget to precipitation to be ~3,500–4,000 km and demonstrate its relation to the spatial scale of precipitation changes under climate change.
The Semidirect Effect of Combined Dust and Sea Salt Aerosols in a Multimodel Analysis
Authors: Amiri‐Farahani Anahita , Allen Robert J. , Li King‐Fai , Chu Jung‐Eun 
Published: August 2019

AbstractTo date, very few studies have focused on dust and sea salt cloud interactions, particularly the semidirect effect (SDE) that results from changes in column temperature and moisture. Here, we isolate the SDE using several climate models driven by semiempirical dust and sea salt direct radiative effects. The global annual mean SDE varies from 0.01 to 0.10 W/m2, with the bulk of the signal coming from an increase in shortwave radiation. This is consistent with decreases in low cloud over ocean due to cloud burn‐off and reductions in midlevel cloud over land due to atmospheric stabilization and decreased convection. Overall, longwave effects weaken the positive SDE but with opposing effects over land and sea. High cloud is reduced over land but enhanced over sea. We conclude that dust and sea salt likely exert a global mean warming effect through cloud rapid adjustments.