bluuebunny/crossref_metadata_2025_split huggingface dataset:
Zonda wind classification using machine learning algorithms
Authors: Otero Federico , Araneo Diego 
Published: June 2020

AbstractZonda wind is a typical downslope windstorm over the eastern slopes of Central Andes, in Argentina, which produces extremely warm and dry conditions creating substantial socioeconomic impacts. To achieve the Zonda wind classification, objective methods based on supervised machine learning (ML) algorithms are used. ML training and supervision is based on the subjective Zonda wind classification assessing the total hourly data that correspond to Zonda wind observations for three surface stations longtime series. ML algorithms includes; the linear discriminant analysis (LD), linear support vector machine (SVM), k nearest neighbours (k‐NN), logistic regression (LR) and classification trees. Metrics obtained from the confusion matrix are used to compare the models' skills in class separation. Considering event‐based statistics, the obtained probability of detection values locate all models above 85% with a probability of false detection lower than 0.523% and a missing ratio below 15%. From an alarm‐based perspective, algorithms show values below 11.42% in false alarm rate, lower than 0.7% in missing alarm ratio and higher than 88.85% in correct alarm ratio. The false negative rate occurs mostly from August to December, where the onset time of the events presents greater difficulty in the classification than the offset, while the false alarm increases in June and October months. Models skills reveal that k‐NN, SVM and LR are better discriminators than LD and classification tree. The high efficiency of these models indicates that ML classification models could be used for the phenomenon diagnosis.
Tailored Polarization Conversion and Light‐Energy Recycling for Highly Linearly Polarized White Organic Light‐Emitting Diodes
Authors: Zhou Lei , Zhou Yun , Fan Bao‐Lu , Nan Feng , Zhou Guang‐Hong , Fan Yuan‐Yuan , Zhang Wen‐Jun , Ou Qing‐Dong 
Published: June 2020

AbstractDirectly linearly polarized light emission from organic light‐emitting diodes (OLEDs), as an important functional expansion, is an intriguing and attractive research topic due to its increasing importance in various applications. Until now, however, the limited efficiency and inadequate polarization ratio constitute two major hurdles for real application. In this work, high‐efficiency linearly polarized white OLEDs with an ultrahigh polarization ratio are achieved by using integrated dielectric/metal nanograting and nanorelief speckle image holography metasurfaces. In the devices, the integrated grating behave as a polarizer to select the transverse magnetic wave (TM) component and simultaneously reflect the transverse electric wave (TE) counterpart over the whole emission spectrum, while the metasurfaces gather the otherwise waste TE‐polarized light reflected by the grating and transform it into reusable TM‐polarized light. This synergistic energy‐light recycling system leads to dramatically boosted device efficiency and polarization ratio, i.e., a power efficiency 21.4 lm W−1 (@ 1000 cd m−2), and an extinction ratio of 17.8 dB (@ V = 5 V) for the polarized white OLEDs. The presented paradigm for simultaneous polarization controlling and efficiency boosting in white OLEDs is expected to advance the OLED techniques in device reconfigurability for future multifunctional applications.
Research on the influence of the lubrication status at the inlet on the lubrication characteristics of engine piston ring
Authors: Sun Jun , Zhu Jianxiong , Wang Hu , Zhao Xiaoyong , Teng Qin , Ren Yanping , Zhu Guixiang , Zhang Xiao , Gao Yaming 
Published: June 2020

AbstractIn current researches on the lubrication of engine piston ring, some were based on a hypothesis that the piston ring is on a flooded lubrication status. Although some others belong to the starved lubrication analysis, the one‐dimensional model, a certain form of starved lubrication status or simplified manner were used. In this paper, on the basis of the equations about the lubricating oil flow‐rate and control volume, a flow model of lubricating oil in the piston ring‐cylinder liner conjunction is established, and the influence of the situation of supplied lubricating oil film at the piston ring inlet on the two‐dimensional starved lubrication characteristics of piston ring for a four‐stroke engine is studied. The results indicate that the lubrication condition at the piston ring inlet has significant impact on the lubrication characteristics of piston ring. When the supplied lubricating oil at the piston ring inlet increases, the minimum film thickness of piston ring will increase, meanwhile the maximum film pressure, asperity contact force, friction force and power loss will decrease. If the film thickness at the piston ring inlet is smaller, the increase of the supplied film thickness can improve obviously the lubrication characteristics of piston ring.
Ionically Conductive Hydrogel with Fast Self‐Recovery and Low Residual Strain as Strain and Pressure Sensors
Authors: Sun Xia , Yao Fanglian , Wang Chenying , Qin Zhihui , Zhang Haitao , Yu Qingyu , Zhang Hong , Dong Xiaoru , Wei Yuping , Li Junjie 
Published: June 2020

AbstractHydrogel‐based sensors have attracted enormous interest due to their broad applications in wearable devices. However, existing hydrogel‐based sensors cannot integrate satisfying mechanical performances with excellent conductivity to meet the requirements for practical application. Herein, an ionically conductive hydrogel with high strength, fast self‐recovery, and low residual strain is constructed through a facile soaking strategy. The proposed ionically conductive double network hydrogel is achieved by combining chemically crosslinked polyacrylamide and physically crosslinked gelatin network followed by sodium citrate solution immersing. The obtained hydrogel has a tensile strength of 1.66 MPa and an elongation of 849%. The ionically conductive hydrogels can be utilized as both strain and pressure sensors with high sensitivity. Moreover, they can be used as ionic skin to monitor various human movements precisely, demonstrating their promising potential in wearable devices and flexible electronics.
A Pooled Analysis From Phase 2b and 3 Studies in Japan of Istradefylline in Parkinson's Disease
Authors: Hattori Nobutaka , Kitabayashi Hiroki , Kanda Tomoyuki , Nomura Takanobu , Toyama Keizo , Mori Akihisa 
Published: June 2020

AbstractBackgroundCharacterization of patient factors associated with istradefylline efficacy may facilitate personally optimized treatment.ObjectivesWe aimed to examine which patient factors are associated with favorable istradefylline treatment outcomes in PD patients with motor complications.MethodsWe performed a pooled analysis of data from two identical phase 2b and 3 Japanese studies of istradefylline. Logistic regression models were used to assess the association of 12 patient characteristics with favorable outcomes.ResultsOff time reduction and increased good on time with istradefylline provided a significantly favorable response in patients aged ≥65 years. Off time reduction was more favorable in patients with ≥8‐hour daily off time at baseline. Improvement in UPDRS Part III was favorable in patients with UPDRS Part III baseline score ≥ 20.ConclusionsSeveral patient factors influenced the effect of istradefylline on motor fluctuations, motor function, activities of daily living, and clinical impression. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
Propagation of wave in a cylindrical waveguide filled with hyperbolic negative index medium
Authors: Bhardwaj Abhinav , Srivastava Kumar Vaibhav , Ramakrishna S. Anantha 
Published: June 2020

AbstractA co‐axial waveguide is filled with an anisotropic hyperbolic medium that has a radial negative component of the tensorial permittivity and permeability. This waveguide has no cutoff frequency for propagating transverse electric and transverse magnetic modes. These modes of propagation are described by Bessel functions of first and second kinds (Neumann function) with an imaginary order. This feature of below cutoff propagation is useful for miniaturizing the size of the waveguide. Further, the double negative character of the radial components of the permittivity and permeability also occasion a better impedance match of the waveguide to free space. Such waveguide can be projected to be useful as miniaturized efficient coupler and imaging probes.
Scalable Formation of Concentrated Monodisperse Lignin Nanoparticles by Recirculation‐Enhanced Flash Nanoprecipitation
Authors: Conner Cathryn G. , Veleva Anka N. , Paunov Vesselin N. , Stoyanov Simeon D. , Velev Orlin D. 
Published: June 2020

AbstractA highly controllable and scalable process for fabrication of large amounts of concentrated lignin nanoparticles (LNPs) is reported. These lignin core nanoparticles are formed through flash nanoprecipitation, however, scaling up of the fabrication process requires fundamental understanding of their operational formation mechanism and surface properties. It is shown how a semicontinuous synthesis system with a recirculation loop makes it possible to produce flash precipitated lignin nanoparticles in large amounts for practical applications. The roles of the process parameters, including flow rates and lignin concentration, are investigated and analyzed. The results indicate that the LNPs are formed by a process of continuous burst nucleation at the point of mixing without diffusive growth, which yields nanoparticles of highly uniform size following a modified LaMer nucleation and growth mechanism. This mechanism makes possible facile process control and scale‐up. Effective control of the resulting nanoparticle size is achieved through the initial concentration of lignin in the injected solution. The impressive capability to produce suspensions of any predesigned multimodal distribution is demonstrated. The resulting nanofabrication technique can produce large volumes of concentrated LNP suspensions of high stability and tightly controlled size distributions for biological or agricultural applications.
The myth of episodic deflagration in large, unconfined vapor clouds
Authors: Abdel‐jawad Madhat , Gavelli Filippo 
Published: June 2020

AbstractReports and reviews issued by the Health and Safety Executive (HSE) have a wide‐ranging influence that extends well beyond the United Kingdom. One such recent document, RR1113 Review of Vapor Cloud Explosion Incidents, discusses explosions arising from the ignition of large vapor clouds. The report proposes a mechanism called “Episodic Deflagration” which has been proposed as an alternative to Deflagration to Detonation Transition (DDT). Here, we examine the concept and the assumptions behind this mechanism in detail. We examine fundamentals purported to characterize this mechanism such as the so‐called cumulative build‐up of pressure over time, an assumed stationary flame state and the radiant heating mechanism proposed as the basis for this postulated phenomenon. We show that the concept is fundamentally flawed and built on unrealistic assumptions, leading to the conclusion that this phenomenon should be ignored.
Secondary analysis of case‐control association studies: Insights on weighting‐based inference motivate a new specification test
Authors: Li Fan , Allen Andrew S. 
Published: June 2020

AbstractCase‐control sampling is frequently used in genetic association studies to examine the relationship between disease and genetic exposures. Such designs usually collect extensive information on phenotypes beyond the primary disease, whose associations with the genetic exposures are also of great interest. Because the cases are over‐sampled, appropriate analysis of secondary phenotypes should take into account this biased sampling design. We previously introduced a weighting‐based estimator for appropriate secondary analysis, but have not thoroughly explored its statistical properties. In this article, we revisit our previous estimator to offer new insights and methodological extensions. Specifically, we extend our previous estimator and construct its more general form based on generalized least squares (GLS). Such an extension allows us to connect the GLS estimator with the generalized method of moments and motivates a new specification test designed to assess the adequacy of the disease model or the weights. The specification test statistic measures the weighted discrepancy between the case and control subsample estimators, and asymptotically follows a central Chi‐squared distribution under correct disease model specification. We illustrate the GLS estimator and specification test using a case‐control sample of peripheral arterial disease, and use simulations to further shed light on the operating characteristics of the specification test.
Discovery of Dual Inhibitors of Acetyl and Butrylcholinesterase and Antiproliferative Activity of 1,2,4‐Triazole‐3‐thiol: Synthesis and In Silico Molecular Study
Authors: Siddiqui Sabahat Zahra , Arfan Muhammad , Abbasi Muhammad Athar , Aziz‐ur‐Rehman  , Shah Syed Adnan Ali , Ashraf Muhammad , Hussain Safdar , Saleem Rahman Shah Zaib , Rafique Rafaila , Khan Khalid Mohammed 
Published: June 2020

AbstractThe aim of this current study is to discover effective acetyl and butrylcholinesterase enzyme inhibitors. A concise library of S‐alkylated/arylated‐4‐ethyl‐5‐(4‐methoxyphenyl)‐4H‐1,2,4‐triazole‐3‐thiols 5–18 was synthesized by using a multistep reaction sequence. The compounds were characterized by using a combination of several spectroscopic techniques including FT‐IR, 1H‐NMR, 13C‐NMR and EI‐MS. All derivatives 5–18 were tested for in vitro AChE and BChE inhibitory activity. It is worth mentioning that all synthetic compounds exhibited moderate inhibition judged by the potency of action, that is inhibition in the range of 45.87 ± 0.92 ‐ 435.15 ± 1.69 μM for AChE, and 3.27 ± 0.81 ‐ 346.25 ± 1.36 μM for BChE. Anti‐proliferative activity results suggested that the derivative with longest alkyl‐chains at S‐atom of the triazole moiety was most potent with 4.91% cell viability at 25 μM and 2.97% cell viability at 50 μM and showed selectivity of inhibition of BChE over AChE at the tested concentrations providing a hit for subsequent structure optimization. Lastly, the in silico studies were performed to ascertain the binding interactions of compound with the active site of enzymes.
An Eco‐Friendly and Efficient Approach for the Synthesis of Tetrazoles via Fe3O4/HT‐GLYMO‐TA as a New Recoverable Heterogeneous Nanostructured Catalyst
Authors: Ghasemzadeh Maryam Sadat , Akhlaghinia Batool 
Published: June 2020

AbstractTannic acid immobilized on functionalized magnetic hydrotalcite (Fe3O4/HT‐GLYMO‐TA) was synthesized as a durable, environmentally‐friendly and magnetic nanostructured catalyst for the synthesis of 5‐ and 1‐substituted‐1H‐tetrazoles. The nanocatalyst was characterized by several methods, Fourier transform infrared (FT‐IR), X‐ray diffraction (XRD) analysis, transmission electron microscopy (TEM), field emission scanning electron microscopy (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDS), EDS‐map, thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM) and CHNS analysis. The results displayed that the superparamagnetic catalyst with a mean particle size of approximately 23–27 nm has a plate‐like shape. The catalytic activity of this new nanostructured catalyst resulted in the preparation of tetrazoles with high yields. Additionally, this novel procedure offers a plethora of benefits including short reaction times, the simplicity of operation, the ease of purification procedure and the reusability of nanocatalyst for at least eight cycles.
Graphene Oxide Catalyzed One‐pot Synthesis of Pyrimido[4,5‐b]quinolinone‐2,4‐diones and their Biological Evaluation
Authors: Singha Rabindranath , Basak Puja , Bhattacharya Malay , Ghosh Pranab 
Published: June 2020

AbstractA simple and highly efficient method for the synthesis of 5‐aryl‐pyrimido quinoline 2,4‐diones has been demonstrated. Graphene oxide (GO) has proved to be a new class of carbocatalyst for the synthesis of pyrimido[4,5‐b]quinolinone‐2,4‐diones through one‐pot three component reaction using aromatic amines, aldehydes, and barbituric acid. The antimicrobial activity of the synthesized compounds was examined for the first time. The effects e. g. reaction temperature, catalyst amount, reaction time, the molar ratio of reactants were investigated. The GO could easily be recovered and reused upto 5th run without loss of its catalytic activity.
Multifunction Sandwich Composite SERS Imprinted Sensor Based on ZnO/GO/Ag for Selective Detection of Cyfluthrin in River
Authors: Li Hongji , Ren Chuqi , Meng Jingjing , Gao Yan , Ren Tong , Li Yue , Qiao Yu , Liu Chunbo , Che Guangbo 
Published: June 2020

AbstractAs a sensitive analytical measurement, surface enhanced Raman scattering (SERS) technique is gradually attracting the attention of scientists. However, traditional SERS substrate can be easily contaminated and uncomfortably applied into detection in the complex practical samples. In order to enlarge the SERS detection field, in this work, a novel multilayer nanocomposite synthesized by ZnO/GO/Ag is used as SERS substrate. This material can effectively degrade the pollutants absorbed on its surface. Furthermore, the surface of ZnO/GO/Ag is coated by molecular imprinted polymers (MIPs) to synthesize the sandwich SERS imprinted sensor (ZnO/GO/Ag‐MIPs, ZGA‐MIPs), which effectively improves the property of practical sample detection. Through the modern instruments analyzing, the ZGA‐MIPs exhibit satisfying SERS detection properties and selectivity. Importantly, ZGA‐MIPs also possess self‐cleaning property and present favorable recycling capacity. This work provides a novel approach to the SERS detection in the practical samples.
Automated Synthesis of New Quinoxalinetacrines
Authors: Bautista‐Aguilera Óscar M. , Ismaili Lhassane , Chioua Mourad , Iriepa Isabel , Ángeles Martinez‐Grau Marìa , Beadle Christopher D. , Vetman Tatiana , López‐Muñoz Francisco , Marco‐Contelles José 
Published: June 2020

AbstractTacrine was the first acetylcholinesterase inhibitor approved for the treatment of Alzheimer's disease although its use has been limited and finally abandoned because of side effects including hepatic toxicity. Based on 1,2,3,4‐tetrahydroquinolino[2,3‐b]quinoxalin‐12‐amine (QT78), a recently reported cholinesterase inhibitor, less toxic and potent than tacrine as acetylycholinesterase inhibitor, but more selective against butyrylcholinesterase, herein we report the synthesis of novel quinoxalinetacrines QT1‐11, a series of hybrids designed by juxtaposition of tacrine and quinoxaline. The target compounds have been obtained in moderate yields from 3‐aminoquinoxaline‐2‐carbonitrile and suitable commercially available ketones, under microwave‐promoted Friedländer reactions catalyzed by aluminium trichloride or indium trichloride. These compounds were synthesized remotely in Eli Lilly's Automated Synthesis Laboratory as part of their Open Innovation Drug Discovery program.
Confinement Growth of Layered WS2 in Hollow Beaded Carbon Nanofibers with Synergistic Anchoring Effect to Reinforce Li+/Na+ Storage Performance
Authors: Wu Huayu , Chen Xing , Qian Chen , Yan Hui , Yan Chenyi , Xu Nuo , Piao Yuanzhe , Diao Guowang , Chen Ming 
Published: June 2020

AbstractNovel nitrogen doped (N‐doped) hollow beaded structural composite carbon nanofibers are successfully applied for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). Tungsten disulfide (WS2) nanosheets are confined, through synergistic anchoring, on the surface and inside of hollow beaded carbon nanofibers (HB CNFs) via a hydrothermal reaction method to construct the hierarchical structure HB WS2@CNFs. Benefiting from this unique advantage, HB WS2@CNFs exhibits remarkable lithium‐storage performance in terms of high rate capability (≈351 mAh g−1 at 2 A g−1) and stable long‐term cycle (≈446 mAh g−1 at 1 A g−1 after 100 cycles). Moreover, as an anode material for SIBs, HB WS2@CNFs obtains excellent long cycle life and rate performance. During the charging/discharging process, the evolution of morphology and composition of the composite are analyzed by a set of ex situ methods. This synergistic anchoring effect between WS2 nanosheets and HB CNFs is capable of effectively restraining volume expansion from the metal ions intercalation/deintercalation process and improving the cycling stability and rate performance in LIBs and SIBs.
(−)‐o‐[11C]methyl‐trans‐decalinvesamicol ((−)‐[11C]OMDV) as a PET ligand for the vesicular acetylcholine transporter
Authors: Miwa Daisuke , Kitamura Yoji , Kozaka Takashi , Shigeno Taiki , Ogawa Kazuma , Taki Junichi , Kinuya Seigo , Shiba Kazuhiro 
Published: June 2020

AbstractTo develop a PET imaging agent to visualize brain cholinergic neurons and synaptic changes caused by Alzheimer's disease, (−)‐ and (+)‐o‐[11C]methyl‐trans‐decalinvesamicol ([11C]OMDV) were isolated and investigated for differences in not only their binding affinity and selectivity to vesicular acetylcholine transporter (VAChT), but also their in vivo activities. [11C]OMDV has a high binding affinity for VAChT both in vitro and in vivo. Racemic OMDV and o‐trimethylstannyl‐trans‐decalinvesamicol (OTDV), which are precursors for synthesis of [11C]OMDV, were separated into (−)‐optical isomers ((−)‐OMDV and (−)‐OTDV) and (+)‐optical isomers ((+)‐OMDV and (+)‐OTDV) by HPLC. In the in vitro binding assay, (−)‐OMDV(7.2 nM) showed eight times higher binding affinity (Ki) to VAChT than that of (+)‐OMDV(57.5 nM). In the biodistribution study, the blood–brain barrier permeability of both enantiomers ((−)‐[11C]OMDV and (+)‐[11C]OMDV) was similarly high (about 1.0%ID/g) at 2 min post‐injection. However, (+)‐[11C]OMDV clearance from the brain was faster than (−)‐[11C]OMDV. In the in vivo blocking study, accumulation of (−)‐[11C]OMDV in the cortex was markedly decreased (approximately 30% of control) by coadministration of vesamicol, and brain uptake of (−)‐[11C]OMDV was not significantly altered by coadministration of (+)‐pentazocine or (+)‐3‐(3‐hydroxyphenyl)‐N‐propylpiperidine ((+)‐3‐PPP). PET‐CT imaging revealed inhibition of the rat brain uptake of (−)‐[11C]OMDV by coadministration of vesamicol. In conclusion, (−)‐[11C]OMDV, which is an enantiomer of OMDV, selectively binds to VAChT with high affinity in the rat brain in vivo. (−)‐[11C]OMDV may be utilized as a potential PET ligand for studying presynaptic cholinergic neurons in the brain.
Nonlinear behavior of a vibrating axially moving small‐size beam under an electrostatic force
Authors: Alshaqaq Mustafa , Hawwa Muhammad A. 
Published: June 2020

AbstractSmall size (micro/nano)‐scale beams constitute important building blocks of microelectromechanical systems (MEMS)/nanoelectromechanical systems (NEMS). Emerging roll‐based, high rate, manufacturing processes can make these small size‐beams vibrate, while they are axially moving. In this paper, an analytical‐numerical study on the nonlinear transverse vibration of the representative case of axially moving micro‐beam under an electrostatic force is conducted. The analytical model is realized by employing Hamilton's principle together with Galerkin discretization. The method of multiple time‐scales and Runge‐Kutta based numerical scheme are utilized to investigate the nonlinear dynamic behavior of the micro‐beam. Results are obtained for the influence of axial beam velocity and modified couple stress theory length scale parameter (i) on the values of pull‐in instability voltage of the small‐size beam, and (ii) on the small‐size beam nonlinear softening/hardening characteristics. The effect of axial load on the frequency response is investigated.