bluuebunny/crossref_metadata_2025_split huggingface dataset:
STEM and HRTEM studies of accumulated deposits on human tooth surface
Authors: Wakasa Masanobu , Eshita Yoshiyuki , Nakanishi Kuniyuki , Isobe Tsutomu , Manago Kenji , Okamoto Masayuki , Isshiki Toshiyuki 
Published: January 2017

AbstractThe aim of this study was to clarify the fine structure of accumulated deposits on the surface of teeth that are considered to affect the gloss of teeth.The study was carried out using, as specimens, human incisor teeth having gloss, which were extracted from teenage donors and those incapable of showing gloss even by brushing which were extracted from donors in their 50s. Thin longitudinal sections of tooth enamel with accumulated deposits on the surface were prepared by focused ion beam (FIB) milling, and the fine structure was analyzed using a scanning transmission electron microscope (STEM) and a high resolution transmission electron microscope (HRTEM).By FIB, thin longitudinal sections could be prepared from tooth enamel together with organic and inorganic substances accumulated on the surface without artifacts. The accumulated deposits on the surface of teeth having gloss were composed of organic substances. However, it was first revealed by STEM observation that the accumulated solid deposits on the surface of teeth having no gloss had a complicated structure wherein inorganic and organic substances coexisted.It is suggested that the organic substances contain proteins derived from saliva. The inorganic substances were spherical and needle‐like hydroxyapatites (HAs). It is considered that amino acids constituting the proteins affected the nucleus formation and the crystal formation of HA. It is considered that the unevenness of the accumulated deposits existing on the surface of tooth enamel having no gloss causes the decrease in gloss of teeth due to diffuse reflection of light.
Picture this: A field experiment of the influence of subtle affective stimuli on employee well‐being and performance
Authors: Hu Xiaoxiao , Zhan Yujie , Yao Xiang , Garden Rebecca 
Published: January 2017

SummaryPrior literature examining the antecedents of employee affect has largely ignored subtle affective influences in the workplace and their impact on employees' affective experiences and behaviors. A substantial body of evidence from basic psychology research suggests that individuals' affect can be influenced by minimal stimulus input. The primary objective of this research is to take an initial step towards understanding the “real‐world” impact of subtle affective stimuli in the workplace. Specifically, in a field experiment with a within‐subjects design, we collected data from 68 sales representatives and examined the effect of a subtle affective stimulus (i.e., a black‐and‐white picture of a woman smiling printed on the backdrop of paper–pencil surveys) on employees' affect, well‐being, and performance. Results showed that the smiling picture significantly enhanced participants' positive affect, which in turn influenced employees' extra‐role performance and emotional exhaustion. The smiling picture also indirectly influenced employees' in‐role performance and emotional exhaustion via negative affect. Theoretical and practical implications of these findings are discussed at the end of the paper. Copyright © 2017 John Wiley & Sons, Ltd.
Potential effects of land cover change on temperature extremes over Eurasia: current versus historical experiments
Authors: Li Xing , Chen Haishan , Liao Hong , Hua Wenjian , Sun Shanlei , Ma Hedi , Li Xiao , Gao Chujie , Zhu Siguang 
Published: January 2017

ABSTRACTLand use and land cover change (LUCC) is an important external forcing agent of climate change. The comparison of current (2000 A.D.) with historical (1850 A.D.) land cover maps suggests that most of the Eurasian continent has experienced robust and significant LUCC during the past century, especially evident transition from forests to croplands. Therefore, two experiments (control and sensitivity experiments with current and historical land cover maps, respectively) are conducted by using the Community Atmosphere Model Version 5.0 (CAM5.0) coupled with the Community Land Model Version 4.0 (CLM4.0) to investigate the potential effects of LUCC on temperature extremes over Eurasia. Results show significant increases (e.g., 0.2–0.7 °C) in extreme cold indices (e.g., TNn) over central and eastern China, India and mainland Southeast Asia in response to such robust LUCC. Broad and significant decreases (e.g., approximately −1 °C) in extreme warm indices (TXx) are mainly observed in Eastern Europe and western Siberia. Moreover, the effects of LUCC on high and low‐percentile extreme indices of minimum temperature (Tmin) are generally symmetrical, but those for maximum temperature (Tmax) indices are asymmetrical, which are characterized by stronger influences on high‐percentile indices rather than low ones. Further analyses suggest that LUCC‐induced changes in temperature extremes are mostly influenced by shifts in the mean state of Tmin/Tmax. Furthermore, the responses and sensitivities of Tmin/Tmax to LUCC are remarkably distinct among regions. This result mainly occurs because of different LUCC‐induced changes in surface energy components, which depend on the region‐specific climatology of each energy component and the dominant plant functional types.
Potential impacts of solar arrays on regional climate and on array efficiency
Authors: Nguyen Kim C. , Katzfey Jack J. , Riedl John , Troccoli Alberto 
Published: January 2017

ABSTRACTWorld population and industrialization have increased significantly, leading to an increase in global energy demand, mainly relying on fossil fuels. Use of alternative energy sources such as wind, hydro and solar has been steadily increasing. Australia is a vast continent which receives an average 58 million PJ of energy from the sun annually. Given this resource potential, one could envisage construction of massive solar farms to help meet energy demands. If such constructions went ahead, their potential benefits/impacts on the climate over and surrounding the solar arrays would need to be investigated. Here, we study the potential climatic impacts over and in the environment surrounding massive hypothetical solar sites across Australia using a global stretched grid atmospheric model. The solar farms are represented by modelling the effects of perturbing surface albedo and surface roughness. The sensitivity experiments incorporate different combinations of surface albedos, shapes and locations of the solar farms, with a focus on the summer season. Our study suggests that depending on array sizes, locations, orientations and surface albedo (potentially increased by means of highly reflective in‐fill material), the climate over solar arrays could be modified significantly. Over the arrays with positive albedo perturbation, rainfall would decrease by around 30–70%, and daytime maximum air temperatures would decrease up to 10 °C. In addition, solar irradiance would increase by around 5–20%, which combined with the air temperature cooling, would lead to an enhanced solar power yield up to 25%.
How Do Service Quality, Experiences and Enduring Involvement Influence Tourists' Behavior? An Empirical Study in the Picasso and Miró Museums in Barcelona
Authors: Forgas‐Coll Santiago , Palau‐Saumell Ramon , Matute Jorge , Tárrega Salomé 
Published: January 2017

AbstractThis study develops an integrated model that examines how service quality, perceived experiences and enduring involvement determine tourists' behavior. The model proposes that enduring involvement has both a direct and moderating influence on tourists' satisfaction with the destination. Data were collected from 1091 visitors of two museums in Barcelona: the Picasso Museum and the Miró Foundation. The results suggest that visit experience, service quality and involvement are drivers of satisfaction. Satisfaction influences the behavioral intentions of visitors to the museum. In addition, the visitors' level of art involvement negatively moderates the influence of perceived quality and experience on tourists' satisfaction. Copyright © 2017 John Wiley & Sons, Ltd.
MHD Stokes flow and heat transfer in a lid‐driven square cavity under horizontal magnetic field
Authors: Gürbüz Merve , Tezer‐Sezgin M. 
Published: January 2017

This study considers the steady flow of a viscous, incompressible and electrically conducting fluid in a lid‐driven square cavity under the effect of a uniform horizontally applied magnetic field. The governing equations are obtained from the Navier‐Stokes equations including buoyancy and Lorentz force terms and the energy equation including Joule heating and viscous dissipation terms. These equations are solved iteratively in terms of velocity components, stream function, vorticity, temperature, and pressure by using radial basis function approximation. Particular solution, which is approximated by radial basis functions to satisfy both differential equation and boundary conditions, becomes the solution of the differential equation itself. Vorticity boundary conditions are obtained from stream function equation using finite difference scheme. Normal derivative of pressure is taken as zero on the boundary. The numerical results are obtained for several values of Hartmann number and Grashof number for the Stokes approximation (Re << 1). The results show that when the viscous dissipation is present, the flow and isolines concentrate through the cold wall forming boundary layers as Grashof number increases. An increase in the magnetic field intensity retards the effect of buoyancy force in the square cavity, whereas the movement of the upper lid causes buoyancy force to be dominant. The solution is obtained in a considerably low computational expense through the use of radial basis function approximations for the MHD equations. Copyright © 2017 John Wiley & Sons, Ltd.
An axial‐ratio beam‐width enhancement of patch‐slot antenna based on EBG
Authors: Ke Wang Zhao , Yuan Bo , Zhang Xiao Hong , Luo Guo Qing 
Published: January 2017

ABSTRACTA low‐profile axial‐ratio beam‐width enhancement of patch‐slot antenna based on electromagnetic band gap (EBG) structure is proposed. To achieve the circularly polarized property, a diagonal slot is etched in the center of the radiation patch. The traditional mushroom‐like EBG unit cells around the patch are used to suppress the surface wave and improve the front to back ratio. This proposed antenna is printed on the FR4 substrate and fed by a single, conventional coaxial cable with 50 Ω impedance. Measured results show that the impedance bandwidth and 3‐dB axial ratio bandwidth of proposed antenna are 128 and 30 MHz, respectively. By using EBG unit cells, the 3‐dB AR beam‐width can be extended to 232.5° at x–z plane and 258° at y–z plane. The front to back ratio of the antenna is also improved to 25 dB. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:493–497, 2017
A low profile planar MIMO antenna with polarization diversity for LTE 1800/1900 applications
Authors: Malviya Leeladhar , Panigrahi R.K. , Kartikeyan M.V. 
Published: January 2017

ABSTRACTA four port MIMO antenna is proposed with polarization diversity technique to cover LTE 1800/1900 frequency standards. The antenna operates with a 2:1VSWR bandwidth of 560 MHz. The design covers −10 dB impedance band of 1.68–2.24 GHz. The minimum isolation measured among the adjacent and diagonal ports is 13 dB. The antenna offers suitable radiating characteristics for nonline of sight (NLOS) communication to solve the problem of multipath propagation. The gain of the MIMO is more than 3.0 dBi and ECC is less than 0.01 in the whole operating band. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:533–538, 2017
Parametric study of the complementary rose curve resonators (CRCRs) in miniaturization of the transmission lines
Authors: Savitri Betty , Alavikia Babak , Talbi Larbi , Hettak Khelifa 
Published: January 2017

ABSTRACTIn this work, a parametric study of the complementary rose‐curve inclusion in size reduction applications is presented. Through numerical analysis and experimental data, we show the feasibility of controlling the electrical length and thus the physical length of the loaded transmission line by controlling the distributed capacitance of the rose‐curve resonators through their order. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:538–541, 2017
Reflective phase shifter based on wideband multi‐section hybrid coupler in slot‐coupled structure
Authors: Khajepour Somayeh , Asadi Shahrooz , Moradi Gholamreza 
Published: January 2017

ABSTRACTThis article presents a novel reflective phase shifter based on wideband multi‐section 3‐dB hybrid coupler in slot‐coupled structure. By terminating coupled and transmission ports of coupler with rectangular microstrip loads, reflective phase shifter is achieved. It designed on multilayer Rogers RO4003C substrate. The configuration consists of elliptically shaped transmission line and the combination of rectangular and elliptical shaped slots on the ground plane. To improve characteristics of the designed coupler especially in lower frequency band, multi‐section transmission line and altering shape of the slot on ground is proposed. By etching extra rectangular slots on the ground plane the overall size reduction is achieved. Measurement results of the proposed coupler demonstrate coupling of 3 ± 0.7 dB with 90° ± 0.6 phase shift over 1–6 GHz (143%). The novel reflective phase shifter based on the designed coupler provides phase deviation less than 0.7° on 1.2–4.8 GHz (120%). The obtained return loss is better than 10 dB as well as insertion loss is less than 1.2 dB at the frequency band of interest. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:567–573, 2017
Wide‐band dual‐mode bandpass filter using a modified square‐loop resonator
Authors: Chen Hui , Chen Ke‐Song , Chen Xu 
Published: January 2017

ABSTRACT:A novel and compact microstrip dual‐mode bandpass filter with multi‐transmission zeros is designed, fabricated, and measured in this letter. The presented filter consists of a modified square‐loop resonator (MSLR) with dual‐mode resonant characteristic and an improved input/output defected microstrip structure with a dual‐bandgap feature, which is overlapped with the MSLR at the input/output tapping location. Finally, a planar wideband filter with low insertion loss and high selectivity is simulated by the full‐wave electromagnetism solver, and verified by our circuit experiment. The measured results of proposed filter have agreed well with the simulated ones, and have shown an excellent electric characteristic with −3 dB fractional bandwidth 33.9% at the mid‐band frequency, minimum insertion loss 0.5 dB, maximum return loss better than −20 dB, and four transmission zeros nearby the lower and upper pass‐band edges. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:618–621, 2017
A 6‐GHz spread spectrum clock generation with EMI reduction of 30.2 dB for SATA‐III applications
Authors: Alsuraisry Hamed , Cheng Jen‐Hao , Lin Jian‐An , Kuo Yen‐Hong , Tsai Jeng‐Han , Huang Tian‐Wei 
Published: January 2017

ABSTRACTIn this letter, a 6‐GHz spread spectrum clock generation for Serial AT Attachment Generation 3 (SATA—III) applications in 0.18‐pm CMOS technology is presented. The 3rd‐order loop filter is to reduce the ripple of control voltage of VCO and the loop bandwidth is 625 KHz. With the aid of second‐order delta‐sigma (ΔΣ) modulator and triangular profile counter, the division ratio of divider chain can be changed periodically. The modulation frequency is 37.04 KHz with upper bound of 19 for the triangular profile counter. The proposed circuit spreads 30‐MHz frequency range from 5.97 to 6.0 GHz with an EMI reduction of 20.3 dB. The dc power consumption is 34 mW with a chip size of 0.54 mm2. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:622–624, 2017
Compact planar microstrip branch‐line coupler using equal difference structure
Authors: Chen Ja‐Hao , Yuan Shih‐Yi , Liou Shi‐Rong , Liao Shry‐Sann 
Published: January 2017

ABSTRACTA compact planar microstrip branch‐line coupler using equal difference structures was implemented and measured. Using the equal difference structure effectively reduced the quarter‐wavelength microstrip line and minimized the branch‐line coupler dimension as a result of a novel triangular profile of the structure streamlining the circuit area. Compared with that of conventional planar microstrip branch‐line couplers, the optimized area of the proposed coupler was reduced by 84.2% at a 900 MHz operating frequency. The measured insertion loss, isolation, and return loss performances achieved superior results than 3.9, 23, and 16 dB, respectively, and the measured phase difference between the two output ports was 90° ± 0.1°. Notably, a coupler using equal difference structures can be implemented in standard printed circuit board processes without any lumped elements, bonding wires, or via‐holes, easing integration with wireless communication systems. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:664–668, 2017
A dual band stacked aperture coupled antenna array for WLAN applications
Authors: Agarwal Ayushi , Kaur Amanpreet 
Published: January 2017

ABSTRACTIn this article, a dual band stacked micostrip antenna array is presented for wireless local area network. The antenna is designed and simulated using CST MWSv’14. Stacking of the patches is done to achieve dual band. Further resonant slots are cut on the patch to achieve greater bandwidth. The antenna uses aperture coupled feed with defected ground structure on reduced ground. The antenna is fabricated on FR4 substrate with a dielectric constant of 4.4. The simulated antenna shows a bandwidth of 228.3 MHz from 3.63 to 3.86 GHz and 232 MHz from 5.15 to 5.38 GHz. The simulated gain and envelope correlation coefficient was found to be 6.11 dB and 0.14. The testing of the prototype antenna (to measure S11) is done using vector network analyser. The measured results are matching to the simulated ones. The simulated and the measured results are presented in the article. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:648–654, 2017
Analytical and experimental study of the hexagonal metamaterial based on the distributions of the fields
Authors: Zhang JiaKai , Song YiChuan , Ding Jun , Guo ChenJiang 
Published: January 2017

ABSTRACTIn this article, a simple hexagonal metamaterial is presented. Different from the design method of parameters optimization, the method based on the analysis of the distributions of the electric field, magnetic field, and the surface current distribution is proposed. For verification of proposed analytic method, the retrieval process is carried out. Besides, the situations of the other two frequencies point are studied to further verify the analytic method. The experimental study is introduced as well. The results show that the negative effective permittivity and the negative effective permeability with pass band character is achieved simultaneously in the frequency range between 9.58 GHz to 9.75 GHz, and the comparison between the result of the analysis and the experiment justifies the proposed analytic method. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:720–726, 2017
Employing Two‐stage Derivatisation and GC–MS to Assay for Cathine and Related Stimulant Alkaloids across the Celastraceae
Authors: Tembrock Luke R. , Broeckling Corey D. , Heuberger Adam L. , Simmons Mark P. , Stermitz Frank R. , Uvarov Jessica M. 
Published: January 2017

AbstractIntroductionCatha edulis (qat, khat, mirra) is a woody plant species that is grown and consumed in East Africa and Yemen for its stimulant alkaloids cathinone, cathine and norephedrine. Two Celastraceae species, in addition to qat, have been noted for their stimulant properties in ethnobotanical literature. Recent phylogenetic reconstructions place four genera in a clade sister to Catha edulis, and these genera are primary candidates to search for cathine and related alkaloids.ObjectiveDetermine if cathine or related alkaloids are present in species of Celastraceae other than Catha edulis.MethodsLeaf samples from 43 Celastraceae species were extracted in water followed by basification of the aqueous extract and partitioning with methyl‐t‐butyl ether to provide an alkaloid‐enriched fraction. The extract was derivatised in a two‐stage process and analysed using GC–MS for the presence of cathine. Related alkaloids and other metabolites in this alkaloid‐enriched fraction were tentatively identified.ResultsCathinone, cathine and norephedrine were not detected in any of the 43 Celastraceae species assayed other than Catha edulis. However, the phenylalanine‐ or tyrosine‐derived alkaloid phenylethylamine was identified in five species. Nine species were found to be enriched for numerous sterol‐ and terpene‐like compounds.ConclusionThese results indicate that cathine is unique to Catha edulis, and not the compound responsible for the stimulant properties reported in related Celastraceae species. Copyright © 2017 John Wiley & Sons, Ltd.
Synthesis of Quercetin‐imprinted Polymer Spherical Particles with Improved Ability to Capture Quercetin Analogues
Authors: Pardo Antonelle , Josse Thomas , Mespouille Laetitia , Blankert Bertrand , Dubois Philippe , Duez Pierre 
Published: January 2017

AbstractIntroductionMolecularly imprinted polymers (MIPs) are composed of specific cavities able to selectively recognise a template molecule. Used as chromatographic sorbents, MIPs may not trap related structures due to the high rigidity of their cross‐linking.ObjectiveTo improve the capture of quercetin analogues by modulating the synthesis strategy for a quercetin‐imprinted polymer (Qu MIP).MethodologyAn additional comonomer bearing a short oligoethylene glycol (OEG) unit was used to prepare a Qu MIP that was compared to a traditional one formulated in a similar fashion, but without the OEG‐comonomer. The Qu MIPs were prepared in bead form through fluorocarbon suspension polymerisation. After solid phase extraction (SPE) assessment of their imprinted cavities, the MIPs were evaluated by HPLC for their recognition properties towards quercetin and other polyphenols, including flavonoids, phenolic acids and curcumin. The Qu MIPs were finally SPE‐tested on a white onion extract.ResultsThe incorporation of OEG units modulated the selectivity of the Qu MIP by improving the recognition of quercetin related structures (12–61% increase in the imprinting effect for distant analogues). It also allowed limiting or suppressing non‐specific hydrophobic interactions (decrease of about 10% in the rate of quercetin retention on the non‐imprinted polymer). The SPE application of the MIP to a white onion extract indicates its interest for the selective extraction of quercetin and its analogues.ConclusionThe OEG‐modified Qu MIP appears to be an attractive tool to discover new drug candidates from natural sources by extracting, amongst interfering compounds, structural analogues of quercetin. Copyright © 2017 John Wiley & Sons, Ltd.