bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epoxy‐Based Azopolymers with Enhanced Photoresponsive Properties Obtained by Cationic Homopolymerization
Authors: Ollier Romina P. , Victorel Marianela , Arenas Gustavo F. , Oyanguren Patricia A. , Galante María J. , Schroeder Walter F. 
Published: September 2017

AbstractAzopolymers are highly versatile materials due to their unique photoresponsive properties. In this contribution, a novel azo‐modified epoxy network is synthesized by cationic homopolymerization with boron trifluoride monoethylamine (BF3.MEA) complex as initiator. The effect of the addition of a fixed content of amino‐functionalized azo chromophore, Disperse Orange 3, into the polymer matrix is studied in detail. First of all, the thermal curing cycle is optimized by means of differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) measurements. Then, the resulting bulk azo‐modified epoxy networks are characterized by means of thermogravimetric analysis (TGA), FTIR, DSC, UV–vis spectroscopy, and rheological measurements. Finally, the optical response of thin films of these materials is determined. The results evidence that azo‐modified epoxy networks obtained by cationic polymerization with optimized curing cycle display high Tg values, high maximum photoinduced birefringence, fast writing speed, and exceptionally high remnant anisotropy. Therefore, this material is a promising candidate to be used for optical storage applications.
Managerial time constraints and young worker productivity: Natural experiments with NFL rookies
Authors: Allen W. David , Curington William P. 
Published: September 2017

AbstractThe 2011 National Football League lockout and movement of the 2014 draft to a later date compressed the off‐seasons preceding the 2011 and 2014 seasons, exogenously tightening time constraints within which managers—head coaches and their staffs—engage in short‐run training of players. We exploit these natural experiments to investigate how this impacted the productivity of young workers (National Football League rookies). Results estimated for a sample of over 1,500 rookies support hypotheses emanating from an economic model of worker training time allocation and indicate reduced productivity along several dimensions. Survival analysis shows evidence of shorter player career durations along certain lines, suggesting longer term consequences.
Experimental study on the microwave processing of waste tyre rubber aggregates to enhance their surface properties for their use in rubberized bituminous mixtures
Authors: Ateeq Muhammad , Al‐Shamma'a Ahmed 
Published: September 2017

AbstractThis experimental study uses the microwave technology to process the waste tyre rubber aggregates to enhance the interaction properties of waste rubber and bitumen by smoothing its surface. This was to make the waste rubber less reactive to the bitumen sample at the elevated temperatures of around 140–170°C. Parameters such as the microwave power, the height of the sample inside the processing chamber, and the processing time have been considered and optimized. The results show that the microwave processing technique designed in this study has significantly smoothened the surface of waste rubber. Scanning electron microscope surface analysis has been carried out to confirm the changes and smoothness of the rubber surface in comparison with the untreated waste rubber aggregates. In addition, microwave spectroscopy analysis has been carried out to confirm the reduction in the absorption properties of waste rubber. The microwave curves of the bitumen samples extracted from the treated rubber–bitumen blend are comparable with the pure bitumen sample with minute shifts in the resonant peaks. The results show the potential of the technique and recommends designing a dedicated processing unit to further improve it through parameters such as volumetric and uniform surface treatment, penetration depth of the microwaves.
Quasi‐Yagi microstrip antenna device design for directive wideband ISM application
Authors: da Silva Isaac Barros Tavares , da Silva Sandro Gonçalves , da Silva Monique Fernandes , de Andrade Humberto Dionísio 
Published: September 2017

AbstractThis paper presents a directive quasi‐Yagi antenna designed to ISM band application at 2.45 GHz. The directors application was analyzed, compared and the better performance antenna was manufactured. The obtained measured results presented an agreement with the performed simulations 1% error and bandwidth 27.39%, from 2.3 GHz to 3.03 GHz.
Duplexing patch antenna design using substrate integrated waveguide cavities
Authors: Ho Min‐Hua , Hong Wanchu , Guan Pei‐Hong , Chang Geng‐Gui 
Published: September 2017

AbstractThis article presents the design of the novel duplexing patch antenna built by integrating one (or two) radiation patch with one (three) substrate integrated waveguide cavity (SIWC). The duplexing antenna's I/O ports are in a single‐ended form in the single‐SIWC case, and the I/O ports can be either a single‐ended or a balanced form in the three‐SIWC design. In the latter, two radiating patches are used on both sides of the SIWC for the bi‐directional radiation. This double patches configuration effectively widens the antenna's radiation coverage by radiating energy into both the front‐ and back‐side half spaces. The broad‐side radiation pattern on both the front‐ and back‐side of the SIWC is observed in the double patches design. The duplexing antenna exhibits a very narrow fractional bandwidth (<1.7%) and a guaranteed isolation (>40 dB) between the two duplexing ports in the single‐ended I/O case. In the balanced one, the differential (common) mode isolations are larger than 40 (58) dB, and the common mode (CM) return losses, which stand for the quality of CM suppressions, are <0.3 dB.
Controllable frequency and polarization THz filter based on graphene fish‐scale metamaterial
Authors: Dmitriev Victor , Nascimento Clerisson , Lima Roberto , Prosvirnin Sergey L. 
Published: September 2017

AbstractIn this work, we propose and numerically analyze a new electromagnetic polarization filter in THz region based on graphene fish‐scale structure. The array is composed by graphene strips placed on a metallized dielectric substrate. The filter can operate in two different frequency regions that can be shifted in frequency by appropriate choice of width of the graphene ribbons. We present as an example, at f1 = 0.483 THz, the structure possesses the reflection coefficient of −0.38 dB for the incident waves with x‐polarization and −48.05dB for the y‐polarized ones, while at f2 = 0.792 THz, the reflection coefficients are −47.25 dB for x‐polarization and −0.86 dB for y‐polarization. The physics of the device is based on surface plasmon polariton (SPP) resonances in the graphene. The central frequency can be dynamically adjusted by changing the chemical potential (ie, by an external voltage for example) of the graphene strips.
Minimized multi‐layer substrate integrated waveguide 3‐dB small aperture coupler
Authors: Liu Shui , Xu Feng 
Published: September 2017

AbstractA multi‐layer 3‐dB substrate integrated waveguide coupler is presented in this article. As a promising technique, the multi‐layer substrate integrated waveguide has been widely used in microwave and millimeter circuits and systems for its decrease in size. This design combines the Bethe hole coupling theory with the SIW technology to reduce the height and integrate with other planar circuits. More importantly, the strong coupling (3‐dB) coupler presented in this article utilizes the higher frequency band of TE10 mode to get a relatively bigger radius of aperture and in turn reduce the number of coupling sections, which significantly decrease the size of the coupler. The simulated results are in good agreement with the measured data.
Optically transparent frequency selective surface for ultrawideband applications
Authors: Can Sultan , Kapusuz Kamil Yavuz , Yilmaz Asım Egemen 
Published: September 2017

AbstractA multilayer ultra‐wideband frequency selective surface (FSS), which filters the frequency range between 3.38 and 4.66 GHz is presented. The proposed structure having a transparent substrate allows the light pass through itself, while it filters the electromagnetic waves at the frequency band of interest; and it has a bandwidth of 1.28 GHz. For the FSS structure, a transparency level of 52.5% obtained with a fractional bandwidth value of 32%. The structure is examined layer by layer; and the proposed FSS structures are evaluated in terms of bandwidth and transparency level.
Computer controlled multi‐shot frequency‐resolved optical gating diagnostic system for femtosecond optical pulse measurement
Authors: Imran T. , Hussain M. , Figueira G. 
Published: September 2017

AbstractThe control and data acquisition of homemade, second harmonic generation (SHG) multi‐shot frequency‐resolved optical gating (FROG) diagnostic technique reported here. We have designed and developed the computer controlled multi‐shot FROG diagnostic system using reflecting optics to minimize the dispersion while LabVIEW software has employed to control and data acquisition. The femtosecond laser system at laboratory for intense lasers (L2I) optimized and characterized using LabVIEW‐based FROG system. We have measured and retrieved the oscillator and compressed amplified laser pulse profiles in temporal domains having full width half maximum (FWHM) of 150 and 270 fs, respectively, and relatively small temporal phase ∼1 radians peak to peak variations with FROG error ∼0.003. The grating detuning data acquired in the form of the single data file to observe the FROG trace pattern evaluation with the change of grating positions to confirm the reliability of the LabVIEW‐based FROG system.
Design optimization of RF low noise amplifier in twin‐well CMOS process
Authors: Jhon Hee‐Sauk , Jeon Jongwook , Kang Myunggon 
Published: September 2017

AbstractThis article presents an optimization technique aiming to improve gain and noise performances simultaneously, through the design of a cost‐effective low noise amplifier (LNA) in a mixed‐signal CMOS process without an RF triple‐well option. To alleviate the inherent body‐effect within a twin‐well MOS transistor, we applied a transmission‐line based source degeneration inductor Ls instead of a conventional spiral in the RF amplifier. In our design, without additional DC‐power payment, the gain and noise figures (NF50) improved by 26% and 7.1%, respectively, when compared to the conventional spiral. The proposed LNA was implemented in a 0.18 µm 1‐poly 6‐metal mixed‐signal CMOS process, and achieved a 13.1 dB gain and 2.72 dB noise figure while dissipating 8.76 mA from a 1.4 V supply.
Design of a new compact planar wide band dipole antenna
Authors: Noraei Yeganeh Ali , Mahan Ahmad , Sedighy Seyed Hassan , Chamaani Somayyeh 
Published: September 2017

AbstractA new planar compact wideband dipole antenna is presented. The proposed antenna radiation pattern is omnidirectional and very stable in the operation bandwidth with good gain flatness and low cross polarization. Three cases of the proposed antenna are simulated by linear scaling of the designed antenna which proves the design flexibility. Finally, one case of the designed antenna is fabricated and measured. This antenna which works between 1.265 GHz to 3.98 GHz has very compact dimensions 82.4 mm × 45.5 mm (0.35l1 × 0.169l1, l1 is the wavelength in the start of bandwidth), stable radiation patterns and low cross polarization. These good specifications prove the antenna design capability and ability for wideband communication system applications.
Extremely compact microstrip branch‐line coupler with a novel fold structure
Authors: Chen Ja‐Hao , Yuan Shih‐Yi , Liou Shi‐Rong 
Published: September 2017

AbstractAn extremely compact 900‐MHz microstrip branch‐line coupler with a novel fold structure was proposed. A novel profile of the fold structure prevented the overlapping of stub lines to minimize the branch‐line coupler dimensions. The measured insertion, isolation, and return losses of the proposed coupler were 3.94, 38.2, and 23.9 dB, respectively, and the measured phase difference between the two output ports was 90° ± 0.1°. Compared with the optimized area of a conventional branch‐line coupler, the optimized area of the proposed coupler was reduced to 14.9%. Notably, the proposed coupler can be easily integrated with wireless communication systems because it can be implemented using standard printed circuit board etching processes without any lumped elements, bonding wires, or via holes.
Fast segmentation of kidney components using random forests and ferns
Authors: Jin Chao , Shi Fei , Xiang Dehui , Zhang Lichun , Chen Xinjian 
Published: September 2017

PurposeThis paper studies the feasibility of developing a fast and accurate automatic kidney component segmentation method. The proposed method segments the kidney into four components: renal cortex, renal column, renal medulla, and renal pelvis.MethodIn this article, we have proposed a highly efficient approach which strategically combines random forests and random ferns methods to segment the kidney into four components: renal cortex, renal column, renal medulla, and renal pelvis. The proposed method is designed following a coarse‐to‐fine strategy. The initial segmentation applies random forests and random ferns with a variety of features, and combines their results to obtain a coarse renal cortex region. Then the fine segmentation of four kidney components is achieved using the weighted forests‐ferns approach with the well‐designed potential energy features which are calculated based on the initial segmentation result. The proposed method was validated on a dataset with 37 contrast‐enhanced CT images. Evaluation indices including Dice similarity coefficient (DSC), true positive volume fraction (TPVF), and false positive volume fraction (FPVF) are used to assess the segmentation accuracy. The proposed method was implemented and tested on a 64‐bit system computer (Intel Core i7‐3770 CPU, 3.4 GHz and 8 GB RAM).ResultsThe experimental results demonstrated the high accuracy and efficiency for segmenting the kidney components: the mean Dice similarity coefficients were 89.85%, 80.60%, 86.63%, and 77.75% for renal cortex, column, medulla, and pelvis, respectively, for right and left kidneys. The computational time of segmenting the whole kidney into four components was about 3 s.ConclusionsThe experimental results showed the feasibility and efficacy of the proposed automatic kidney component segmentation method. The proposed method applied an efficient weighted strategy to combine random forests and ferns, making full use of the advantages of both methods. The novel potential energy features help random forests effectively segment the kidney components and the background. The high accuracy and efficiency of our method make it practicable in clinical applications.
Identification and Functional Analysis of Chitin Synthase A in Oriental Armyworm, Mythimna separata
Authors: Zhai Yifan , Fan Xiaobin , Yin Zhenjuan , Yue Xiangzhao , Men Xingyuan , Zheng Li , Zhang Wenqing 
Published: September 2017

AbstractChitin synthases are very important enzymes for chitin synthesis in various species, which makes them a specific target of insecticides. In the present study, the function of the chitin synthase A (CHSA) gene isolated from Mythimna separate is investigated. The majority of dsMysCHSA treated larvae (89.50%) exhibit lethal phenotypes, including three phenotypes with severe cuticle deformations. The dsMysCHSA treatment in adult females affects oogenesis, and significantly reduce the ovary size and the oviposition number compared with controls. To determine how MysCHSA affects female fecundity, combined analyses of RNA‐sequencing (RNA‐Seq) transcriptome and TMT proteome (tandem mass tags) data in M. separata after treatment with MysCHSA‐RNAi is performed. The differentially expressed proteins and genes affect fecundity‐related proteins, energy metabolism, fatty acid metabolism, amino sugars, and nucleotide sugar metabolism pathways. Taken together, these results suggest that MysCHSA acts on M. separata ecdysis and fecundity, and has the potential as a target gene for pest control.
Protein structure prediction using Rosetta in CASP12
Authors: Ovchinnikov Sergey , Park Hahnbeom , Kim David E. , DiMaio Frank , Baker David 
Published: September 2017

AbstractWe describe several notable aspects of our structure predictions using Rosetta in CASP12 in the free modeling (FM) and refinement (TR) categories. First, we had previously generated (and published) models for most large protein families lacking experimentally determined structures using Rosetta guided by co‐evolution based contact predictions, and for several targets these models proved better starting points for comparative modeling than any known crystal structure—our model database thus starts to fulfill one of the goals of the original protein structure initiative. Second, while our “human” group simply submitted ROBETTA models for most targets, for six targets expert intervention improved predictions considerably; the largest improvement was for T0886 where we correctly parsed two discontinuous domains guided by predicted contact maps to accurately identify a structural homolog of the same fold. Third, Rosetta all atom refinement followed by MD simulations led to consistent but small improvements when starting models were close to the native structure, and larger but less consistent improvements when starting models were further away.
Mechanistic in vitro studies confirm that inhibition of the renal apical efflux transporter multidrug and toxin extrusion (MATE) 1, and not altered absorption, underlies the increased metformin exposure observed in clinical interactions with cimetidine, trimethoprim or pyrimethamine
Authors: Elsby Robert , Chidlaw Stephen , Outteridge Samuel , Pickering Sarah , Radcliffe Amy , Sullivan Rebecca , Jones Hayley , Butler Philip 
Published: September 2017

AbstractMetformin is a common co‐medication for many diseases and the victim of clinical drug‐drug interactions (DDIs) perpetrated by cimetidine, trimethoprim and pyrimethamine, resulting in decreased active renal clearance due to inhibition of organic cation transport proteins and increased plasma exposure of metformin. To understand whether area under the plasma concentration–time curve (AUC) increases relate to absorption, in vitro inhibitory potencies of these drugs against metformin transport by human organic cation transporter (OCT) 1, and the apical to basolateral absorptive permeability of metformin across Caco‐2 cells in the presence of therapeutic intestinal concentrations of cimetidine, trimethoprim or pyrimethamine, were determined. Whilst all inhibited OCT1, none enhanced metformin's absorptive permeability (~0.5 × 10−6 cm/sec) suggesting that DDI AUC changes are not related to absorption. Subsequently, to understand whether inhibition of renal transporters are responsible for AUC increases, in vitro inhibitory potencies against metformin transport by human OCT2, multidrug and toxin extrusion (MATE) 1 and MATE2‐K were determined. Ensuing IC50 values were incorporated into mechanistic static equations, alongside unbound maximal plasma concentration and transporter fraction excreted values, in order to calculate theoretical increases in metformin AUC due to inhibition by cimetidine, trimethoprim or pyrimethamine. Calculated theoretical fold‐increases in metformin exposure confirmed solitary inhibition of renal MATE1 to be the likely mechanism underlying the observed exposure changes in clinical DDIs. Interestingly, clinically observed increases in metformin AUC were predicted more closely when the renal transporter fraction excreted value derived from oral metformin administration, rather than intravenous, was utilized in theoretical calculations, likely reflecting the “flip‐flop” pharmacokinetic profile of the drug.
Th@C76. Computational characterization of larger actinide endohedral fullerenes
Authors: Jin Peng , Liu Chang , Li Ying , Li Lanlan , Zhao Yujun 
Published: September 2017

AbstractThe actinide endohedral fullerene Th@C76 was successfully prepared in a very recent experiment (Wang et al., J. Am. Chem. Soc. 2017, 139, 5110) yet without any structural information. In this work, density functional theory calculations revealed that this novel molecule bears a Td(19151)‐C76 cage obeying the isolated pentagon rule. The internal Th atom is off‐centered and resides under a sumanene‐type hexagonal ring, formally donating 4e to the carbon cage. The metal position was rationalized by the structure and charge distribution of the negatively charged cage. Interestingly, an octahedron‐like dynamic trajectory of metal inside the C76 cage at high temperature was found based on the cage symmetry and located transition state structures. Furthermore, the infrared, NMR, and UV/vis spectra of Th@C76 were simulated to assist future experimental characterization.
Expeditious Synthesis and Biological Characterization of Enantio‐Enriched (‐)‐Nutlin‐3
Authors: Fantinati Anna , Bianco Sara , Cristofori Virginia , Cavazzini Alberto , Catani Martina , Zanirato Vinicio , Pacifico Salvatore , Rimondi Erika , Milani Daniela , Voltan Rebecca , Secchiero Paola , Trapella Claudio 
Published: September 2017

AbstractA concise and operationally simple synthesis of enantio‐enriched Nutlin‐3 featuring the desymmetrization of 1,2‐bis(4‐chlorophenyl)ethane‐1,2‐diamine as the key step is described. The easy‐to‐make N‐((1R,2R)‐2‐(3‐(3,5‐bis(trifluoromethyl)phenyl)thioureido)cyclohexyl)‐3,5‐bis(trifluoromethyl)benzamide (and N‐((1S,2S)‐2‐(3‐(3,5‐bis(trifluoromethyl)phenyl)thioureido)cyclohexyl)‐3,5‐bis(trifluoromethyl)benzamide)) involved as anion binding in the key desymmetrization step is the completely recoverable chiral auxiliary. An array of biological tests performed with the 84:16 (‐)‐Nutlin‐3 scalemic mixture showed activities comparable to those of the commercial eutomer.
A Detail Description on Catalytic Conversion of Waste Palm Cooking Oil into Biodiesel and Its Derivatives: New Functionalized Ionic Liquid Process
Authors: Ullah Zahoor , Bustam Mohamad Azmi , Man Zakaria , Khan Amir Sada , Muhammad Nawshad , Sarwono Ariyanti , Farooq Muhammad , Ullah Riaz , Mengal Ali Nawaz 
Published: September 2017

AbstractThis work is focusing on the synthesis and application of new potential ionic liquids (ILs) for biodiesel production from waste palm cooking oil. For this propose total eleven ionic liquids were synthesized containing various types of cations and anions and characterized with nuclear magnetic resonance (NMR), fourier‐transform infrared (FTIR) and elemental analyser (CHNS). The Hammett acidity of the ionic liquids were determined using Ultraviolet (UV) visible spectrometer and correlated with their catalytic properties. The process of biodiesel preparation has been optimized with respect of different factors (catalysts concentrations, methanol to oil ratio, temperature, agitation speed and time) affecting the transesterification reaction. The highest yield of 96.25% for 3‐methyl‐1‐(4‐sulfo‐butyl)‐3H‐imidazol‐1‐ium trifluoromethanesulfonate [BSMIM][CF3SO3] was obtained under optimal conditions. The obtained product was characterized using gas chromatography (GC), NMR, FTIR, Thermogravimetric analysis (TGA) techniques. The physicochemical properties like kinematic viscosity, flash point, density etc were determined and compared with the standard of American Society of Testing Materials (ASTM) and European Standard (EN) methods. The by‐product of reaction i.e. glycerol was further esterified to minimize the waste of glycerol. The kinetic study shows that the transesterification reaction catalysed by prepared ILs follow the pseudo‐first order reaction. The kinetic energy (Ea) of the reaction was calculated around 19.89 kJ/mol.