bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical Evaluation of Fully Automated Elecsys® Syphilis Assay for the Detection of Antibodies of Treponema pallidum
Authors: Li Dongdong , An Jingna , Wang Tingting , Tao Chuanmin , Wang Lanlan 
Published: May 2016

ObjectiveThe resurgence of syphilis in recent years has become a serious threat to the public health worldwide, and the serological detection of specific antibodies against Treponema pallidum (TP) remains the most reliable method for laboratory diagnosis of syphilis. The performance of the Elecsys® Syphilis assay, a brand new electrochemiluminescene immunoassay (ECLIA), was assessed by large amounts of samples in this study.MethodsIn comparison with InTec assay, the Elecsys® Syphilis assay was evaluated in 146 preselected samples from patients with syphilis, 1803 clinical routine samples, and 175 preselected samples from specific populations with reportedly increased rates of false‐positive syphilis test results. Discrepancy samples must be investigated by Mikrogen Syphilis recomline assay.ResultsThere was an overall agreement of 99.58% between two assays (Kappa = 0.975). The sensitivity and specificity of the Elecsys® Syphilis assay were 100.0% (95% CI, 96.8–100.0%) and 99.8% (95% CI, 99.5–100.0%), respectively. The Elecsys syphilis assay displays better sensitivity (100%), specificity (99.8%), PPV (98.7%), and NPV (100%) in 2124 samples enrolled, compared with the InTec assay.ConclusionConsidering the excellent ease of use and automation, high throughput, and its superior sensitivity, especially in primary syphilis, the Elecsys® Syphilis assay could represent an outstanding choice for screening of syphilis in high‐volume laboratories. However, more attention was still needed, or the results must be confirmed by other treponemal immunoassays. The new Elecsys® Syphilis assay is applied to patients with malignant neoplasm or HIV infection.
A 1D numerical model for rapid stress analysis in bipolar junction transistors
Authors: Gnanachchelvi Parameshwaran , Wilamowski Bogdan M. , Jaeger Richard C. , Hussain Safina , Suhling Jeffrey C. , Hamilton Michael C. 
Published: May 2016

SummaryStress effects in semiconductor devices have gained significant attention in semiconductor industry in recent years, and numerical modeling is often used as a powerful tool for stress analysis in semiconductor devices. Here, we present a nontraditional 1D model for fast stress analysis in bipolar junction transistors. Because bipolar transistors are operationally 1D devices, it is possible to speed up the simulation with a 1D numerical model and get results that are comparable with 2D and 3D simulation outcomes. This model consists of a complete numerical algorithm that can be used for stress analysis of bipolar transistors on any plane. Existing 1D simulators take more time as they solve all device equations throughout the device. In contrast, our model optimizes the solutions for different regions with the development and inclusion of specific algorithms. A fractional starting point is introduced for the depletion region to speed up the process further. This way, faster computing time and much higher accuracy can be reached. At the same time, popular 2D and 3D simulators, which are using finite element methods, are naturally much slower, especially if high accuracy is needed. Simulation results of this 1D model match well with the simulation results of a 2D model developed with a commercial technology computer aided design (TCAD) tool. The validity of our model was verified with experimental results and theoretical expectations as well. Copyright © 2016 John Wiley & Sons, Ltd.
Climate change scenarios for Tibetan Plateau summer precipitation based on canonical correlation analysis
Authors: Chen Xiaoyang , You Qinglong , Sielmann Frank , Ruan Neng 
Published: May 2016

ABSTRACTPrecipitation in the Tibetan Plateau (TP) reaches its peak in summer. The seasonal projection skill of a statistical downscaling model (SDM) for summer precipitation in the TP was compared with that of direct model output. The SDM, which is based on canonical correlation analysis (CCA), significantly increased the projection skill. The CCA reveals the flow patterns behind the seasonal projection skill of summer precipitation in the TP between 1961 and 2012 and quantifies its relative contributions. East Asia 500 hPa geopotential height (ZG500), tropical Indian Ocean sea surface temperature (SST) and east Asia 850 hPa meridional water vapour flux (MWVF850), obtained from the Max Planck Institute Earth System Model, low‐resolution (MPI‐ESM‐LR) simulations for phase 5 of the Coupled Model Intercomparison Project under the representative concentration pathway (RCP) 2.6, RCP4.5 and RCP8.5 scenarios are considered as potential predictors. The SDMs are established in 1961–2005, validated in 2006–2012 and applied in 2013–2100. The ensemble canonical correlation (ECC) is also applied to improve projection skill. The following results are obtained: (1) The SDM projection skill for each predictor is higher than that of the MPI‐ESM‐LR climate model, and ECC performs even better. (2) Spatial correlation patterns of different predictors with influence on the TP are well recognized by CCA. The high relevance of ZG500 can be explained by the thermal adaptation theory, that of SST exhibits a canonical Indian Ocean Dipole mode, and MWVF850 shows a simple water vapour link. (3) The amount of summer precipitation in the TP will slightly decrease under RCP2.6 by −3.4 mm decade−1, whereas RCP4.5 and RCP8.5 reveal an increase by 2.4 and 18.4 mm decade−1, respectively.
Diversity–Productivity Trade‐off During Converting Cropland to Perennial Grassland in the Semi‐arid Areas of China
Authors: Liu Yu , Wu Gao‐Lin , Ding Lu‐Ming , Tian Fu‐Ping , Shi Zhi‐Hua 
Published: May 2016

AbstractThe trade‐off between plant community structure and function is an important issue during grassland restoration. It is essential to assess changes of structure and function after converting farmland to grassland. Three restoration stages (5, 15, and 30 years) were studied to determine the optimum time when the trade‐off between diversity and productivity occurs. The results showed that the vegetation coverage, height, and productivity significantly increased, but the species richness, diversity, and density significantly decreased along the restoration time. Grassland community presented a succession from small individuals and high density to larger individuals and lower density. The community changed from being dominated by grass and forb functional groups to being dominated only by the grass functional group. The dominant grass functional group plays a decisive role on community structure and function (productivity, diversity, and density) during grassland succession. Our results suggest that community structure and function were mainly driven by the dominant grass functional group during the long‐term succession. Grassland should be utilized to suppress the leading role of the dominant functional groups in the 20th year for keeping the trade‐off of diversity and productivity. We suggest that the restoration grassland should be considered to use appropriately in the 20th year. Our study could provide a key guidance for maintaining the community structure and function trade‐off for cropland‐converted grassland management in the semi‐arid areas. Copyright © 2016 John Wiley & Sons, Ltd.
High methane emissions from thermokarst lakes in subarctic peatlands
Authors: Matveev Alex , Laurion Isabelle , Deshpande Bethany N. , Bhiry Najat , Vincent Warwick F. 
Published: May 2016

AbstractThe thawing and subsidence of frozen peat mounds (palsas) in permafrost landscapes results in the formation of organic‐rich thermokarst lakes. We examined the effects of palsa degradation on CH4 and CO2 emissions by comparing thermokarst lakes at two peatland locations in subarctic Québec, Canada: in the northern discontinuous permafrost region, and in southern sporadic permafrost where palsas are more rapidly degrading. The lakes were shallow (< 3 m) but stratified at both sites, and most had anoxic bottom waters. The surface waters at both sites were supersaturated in CH4 and CO2, and to a greater extent in the southern lakes, where the surface CH4 concentrations were up to 3 orders of magnitude above air equilibrium. Concentrations of CH4 and CO2 increased by orders of magnitude with depth in the southern lakes, however these gradients were less marked or absent in the North. Strong CH4 and CO2 emissions were associated with gas ebullition, but these were greatly exceeded by diffusive fluxes, in contrast to thermokarst lakes studied elsewhere. Also unusual relative to other studies to date, the surface concentrations of both gases increased as a linear function of water column depth, with highest values over the central, deepest portion of the lakes. Radiocarbon dating of ebullition gas samples showed that the CH4 had 14C‐ages from 760 yr to 2005 yr before present, while the CO2 was consistently younger. Peatland thermokarst lakes may be an increasingly important source of greenhouse gases as the southern permafrost limit continues to shift northwards.
Bioinspired Interface Engineering in Elastomer/Graphene Composites by Constructing Sacrificial Metal–Ligand Bonds
Authors: Huang Jing , Tang Zhenghai , Yang Zhijun , Guo Baochun 
Published: May 2016

It remains a huge challenge to create advanced elastomers combining high strength and great toughness. Despite enhanced strength and stiffness, elastomeric nanocomposites suffer notably reduced extensibility and toughness. Here, inspired by the concept of sacrificial bonding associated with many natural materials, a novel interface strategy is proposed to fabricate elastomer/graphene nanocomposites by constructing a strong yet sacrificial interface. This interface is composed of pyridine‐Zn2+‐catechol coordination motifs, which is strong enough to ensure uniform graphene dispersion and efficient stress transfer from matrix to fillers. Moreover, they are sacrificial under external stress, which dissipates much energy and facilitates chain orientation. As a result, the strength, modulus, and toughness of the elastomeric composites are simultaneously strikingly enhanced relative to elastomeric bulk. This work suggests a promising methodology of designing advanced elastomers with exceptional mechanical properties by engineering sacrificial bonds into the interface.
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Maxwell's equations in an unbounded structure
Authors: Li Peijun , Zheng Gaofeng , Zheng Weiying 
Published: May 2016

This paper is concerned with the mathematical analysis of the electromagnetic wave scattering by an unbounded dielectric medium, which is mounted on a perfectly conducting infinite plane. By introducing a transparent boundary condition on a plane surface confining the medium, the scattering problem is modeled as a boundary value problem of Maxwell's equations. Based on a variational formulation, the problem is shown to have a unique weak solution for a wide class of dielectric permittivity and magnetic permeability by using the generalized Lax–Milgram theorem. Copyright © 2016 John Wiley & Sons, Ltd.
Analysis of planar microwave devices using higher order curl‐conforming triangular prismatic finite elements
Authors: Garcia‐Donoro Daniel , Ting Sioweng , Amor‐Martin Adrian , Garcia‐Castillo Luis E. 
Published: May 2016

ABSTRACTThe evaluation of the accuracy and performance of a higher‐order curl‐conforming triangular prismatic finite element is carried out in this article. The triangular prismatic finite element proposed by the authors is tested by simulating real microwave devices in planar technology. The results obtained using this prismatic element are compared with those obtained using the finite element method reference commercial software HFSS that makes use of higher‐order tetrahedral finite elements. Conclusions about the use of this prismatic element for the analysis of planar microwave devices are given. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1794–1801, 2016
Multiband multistandard frequency synthesizer for mobile TV tuner with LC‐VCO by digital AAC
Authors: Lee Jae Kyung , Kim Young‐Jin , Cho Choon Sik 
Published: May 2016

ABSTRACTTo improve the phase noise (PN) degradation from the tail current source, this article presents an inductor‐capacitor voltage‐controlled oscillator (LC‐VCO) with digitally controlled programmable low drop out. The digital automatic amplitude calibration (AAC) loop is successively implemented to make the voltage swing constant over 900–1940 MHz. A 40–970 MHz frequency synthesizer with switching dividers is implemented to support the operating frequency range of the multiband mobile TV tuners. The PN of −130 dBc/Hz @ 1 MHz offset is obtained at 474 MHz. The PN variation by the help of AAC loop is measured <2.4 dB over −40–85°C. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1838–1841, 2016
A compact internal antenna for LTE/WWAN mobile phone applications
Authors: Yu Cheng‐Chi , Yang Jiin‐Hwa , Chen Chang‐Chih 
Published: May 2016

ABSTRACTA compact multiband internal antenna is proposed for LTE/WWAN mobile phone application. The structure of proposed antenna is composed of a coupling feed L‐shaped monopole and a grounded meandered branch. The coupling feed L‐shaped monopole excites a widely operating band to cover the frequency range of 1750∼2525 MHz for the DCS/PCS/UMTS/LTE/WLAN operation. The grounded meandered branch excites the low frequency operation band to cover the frequency range of 675∼985 MHz for the LTE700/GSM operation. The antenna occupies a small volume of 4 × 14 × 45 mm3 only. The measured result of the 6 dB return loss meets for each operating band. Moreover, the antenna gain and efficiency are measured in good performances. The measured radiation patterns are similar to general monopole antenna. The characteristics of the proposed antenna make it attractive for slim mobile phone applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1834–1838, 2016
Efficiency optimization of WPT system with a planar receiver for mobile applications
Authors: Thuan Nguyen Van , Hyon Kang Seok , Won Jung Chang 
Published: May 2016

ABSTRACTThis letter presents a wireless power transfer (WPT) system with a planar receiver for mobile applications. The proposed WPT system includes a source coil, a transmitter spiral (Tx coil), a rectangular receiver coil (Rx coil), and a rectangular load coil. In order to make a compact receiver, the Rx coil is placed in front of the load coil with a gap of 2 mm. In addition, the relation between the transfer efficiency of WPT system and the capacitance value of Rx coil is established. Experimental results show that by optimizing the capacitor embedded in Rx coil, it is capable of achieving a very high transfer efficiency. With an optimized capacitor Cx = 785 pF on the Rx coil, the transfer efficiency of the proposed system is comparable to a WPT system using a metamaterial (MTM) array. The proposed WPT system operates at 6.78 MHz. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1817–1819, 2016
Acceleration of monostatic shooting and bouncing ray method for inverse synthetic aperture radar image generation
Authors: Lee Yong‐Hee , Bae Ji‐Hoon , Kang Byung‐Soo , Lee Seung‐Jae , Kim Kyung‐Tae 
Published: May 2016

ABSTRACTThe enhanced shooting and bouncing ray (SBR) technique based on the bistatic approximation, which is called the one‐shot inverse synthetic aperture radar (ISAR) technique, has been devised to accelerate the conventional monostatic SBR (CM‐SBR) technique, which is suitable for inverse synthetic aperture radar (ISAR) imaging. However, because of the bistatic approximation, this method results in the distortion of ISAR images. Therefore, to obtain an accurate image, radar returns should be obtained from the monostatic configuration. This paper describes a new method, the ray‐travel map (RTM), which accelerates the CM‐SBR technique while simultaneously considering both the CM‐SBR and the ISAR configuration. Then, we demonstrate that the proposed method can significantly enhance the speed of CM‐SBR, while providing accurate distortion‐free ISAR image. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1848–1855, 2016
Mimo antenna with high frequency selectivity and controllable bandwidth for band‐notched UWB applications
Authors: Huang Hui‐Fen , Xiao Shu‐Guang 
Published: May 2016

ABSTRACTA multiple‐input–multiple‐output (MIMO) antenna with high frequency selectivity and controllable bandwidth, is proposed for band‐notched ultrawideband (UWB) applications. In other words, it has a bandstop‐filter‐like response (second‐order notched band) at the aimed rejected band. It consists of two rectangular printed monopole (PM) elements and a simple stepped ground stub to enhance wideband isolation. For achieving the second‐order rejected band of the IEEE 802.11 wireless local area network (WLAN) band from 5.15 to 5.85 GHz centered at 5.5 GHz, two parasitic modified split‐ring resonators (PMSRRs) and two inverted L‐shaped branches (ILBs), are utilized. Measured results prove a bandwidth of S11 < −10 dB and S12 < −15 dB at 2.8–12 GHz excluding a rejection band of 5–5.95 GHz. Its size is only 32 × 26 mm2 on a cost‐effective FR4 substrate. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1886–1891, 2016
Resonances of electromagnetic oscillations in a spherical metal nanoparticle
Authors: Belyaev B.A. , Tyurnev V.V. 
Published: May 2016

ABSTRACTElectrodynamic analysis of plasma oscillations in a spherical metal nanoparticle is performed. It is shown that typical reduction in the frequency and quality factor of the resonances with increasing nanoparticle radius fades if the mode number grows. Depending on the particle radius, the resonant enhancement of the electric field might considerably either increase or decrease with increasing mode number. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1883–1886, 2016
Low insertion loss microstrip dualband lowpass‐bandpass filter with controllable passband frequencies
Authors: Chen Fu‐Chang , Shao Qiang 
Published: May 2016

ABSTRACTThis letter proposes a novel dualband filter consisting of one lowpass passband and one bandpass passband. The dualband filter is realized using stub‐loaded transmission lines and stepped‐impedance stubs. The key merit of the filter configuration is that the lowpass and bandpass passband frequencies can be flexibly controlled by tuning the impedances and lengths of the transmission lines. Without coupling gap between the transmission lines, the new filter shows low insertion loss and easy for fabrication. To illustrate the concepts, a dualband lowpass‐bandpass filter is designed, fabricated, and measured. The cut‐off frequency of the lowpass filter is selected to be 1 GHz. The central frequency of the bandpass filter is chosen to be 5.2 GHz. Experimental measurements are in good agreement with both simulations and theoretical expectations. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1858–1861, 2016
A fast and accurate technique for FSS and antenna designs based on the social spider optimization algorithm
Authors: Oliveira P. S. , D'Assunção A. G. , Souza E. A. M. , Peixeiro C. 
Published: May 2016

ABSTRACTThis paper presents a fast, accurate, and multifunctional electromagnetic optimization bioinspired technique that uses the social spider optimization algorithm (SSO). The proposed technique is applied to the design of a frequency selective surface (FSS), with Vicsek fractal patch elements, and an ultra wideband antenna (UWB), consisting of a ring monopole. In the proposed (synthesis) technique, the use of a database or the construction of a neural network is not required. The SSO algorithm communicates via scripts directly with the Ansoft HFSS software tool, enabling a good flexibility in the number of parameters to be optimized and reducing the required computation time. The accuracy and efficiency of the proposed technique is confirmed by comparison with experimental results and with other simulation techniques. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1912–1917, 2016
Wearable textile patch antenna fed by proximity coupling with increased bandwidth
Authors: Grilo Marcus , Hiroaki Seko Murilo , Salete Correra Fatima 
Published: May 2016

ABSTRACTThis letter presents the design methodology of a textile rectangular patch antenna with increased bandwidth. The broadening of the antenna operating band is obtained by using a proximity coupling feed line cascaded to a quarter‐wave impedance transformer. The design parameters used to enhance the antenna bandwidth are the widths of the feed line and impedance transformer. The proposed design procedure has been applied to the design of four antennas centered at 2.45 GHz using denim substrate and conductive fabric. All antennas have the same patch dimensions, but they were designed using different values for the widths of the feed line and impedance transformer. The measured 10‐dB return loss bandwidth of the antenna prototypes are 11.2%, 13.4%, 17.0%, and 24.0%, in good agreement with simulated results. The effect of human body proximity and antenna curvature on the performance of the designed antennas has also been analyzed. The antenna configuration investigated has demonstrated to be able to increase the antenna operating band. The proposed design procedure is flexible, allowing the design of antennas with a variety of bandwidth values. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1906–1912, 2016
Increasing the bandwidth of a SiGe HBTLNA with minimum impact on noise figure
Authors: Bimana Abadahigwa , Sinha Saurabh 
Published: May 2016

ABSTRACTThis paper introduces a matching technique for highly sensitive integrated broadband low‐noise amplifiers. Noise matching is achieved by the paralleling of identical input transistors. Impedance matching, based on reducing the number of components to the absolute minimum, is done by using the base‐collector capacitance as network element. Using a 0.13
m silicon‐germanium (SiGe) bipolar complementary metal oxide semiconductor process, simulation results indicate a maximum noise figure of 0.462 dB at room temperature and a return loss better than 10 dB from 300 MHz to 1.4 GHz. The technique demonstrates that SiGe heterojunction bipolar transistors can be used for cost‐effective applications in radio astronomy. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1937–1945, 2016
Coverage area enhancement of 2.4 GHz RFID system using switched beam patch antenna array
Authors: Zahid Kamran , Zahid Zeeshan , Siddique Kashif 
Published: May 2016

ABSTRACTThe paper presents RF front end for coverage area enhancement of RFID systems operating at 2.4 GHz frequency (ISM band). The RF front end consists of a 1 × 4 circularly polarized micro‐strip patch antenna array having the capability of steering its beam in two discrete directions. Delay line phase shifters with two switching states have been used to steer the main beam. The switching is accomplished by using PIN diodes. Using this technique the angular coverage of 56° has been achieved. The antenna array has a peak gain of 8.9 dB. The design is simulated and optimized in antenna design software HFSS and fabricated on FR‐4 substrate. Simulated and measured results are in close agreement. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1945–1948, 2016
Suppression of spurious responses in microstrip half‐wavelength filters combining stagger tuning and resistive attenuation
Authors: Huang Frederick 
Published: May 2016

ABSTRACTStagger tuning and resistive attenuation are combined to attenuate harmonic responses of microstrip filters with half‐wavelength resonators, extending the technique previously used for quarter‐wave resonators. In a measured filter with 0.93 GHz center frequency and 22% bandwidth, the worst spurious peak between 1.3 and 2.7 GHz is about 10 dB better than with stagger tuning alone, while the next two peaks at 2.75 and 3 GHz are suppressed by a further 5 dB. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1955–1957, 2016