bluuebunny/crossref_metadata_2025 huggingface dataset:
A compact reconfigurable ultra‐wideband G‐shaped printed antenna with band‐notched characteristic
Authors: Toktas Abdurrahim , Yerlikaya Mehmet
Published: November 2018

A compact UWB G‐shaped printed monopole antenna with reconfigurable band‐notched characteristic is presented. The antenna design having a low profile of 8 × 27.5 mm2 consists of a G‐shaped radiating element size of 8 × 8 mm2 fed by a microstrip transmission line with a matching line and a defected ground structure. In order to achieve reconfigurable characteristic, a pin diode is inserted between the poles of G‐shaped radiator. When the pin diode is at ON‐state, G‐shaped patch behaves like a ring radiator and the antenna thus operates at whole UWB frequency. On the other hand; when the pin diode is at OFF‐state, the antenna has a band‐notched characteristic corresponds to C‐band and WIMAX band spectrum. The antenna design is parametrically investigated and the proposed design is verified by a prototype. From the measured results, the antenna has switchable characteristic between whole UWB spectrum of 2.8‐12.6 GHz at ON‐state and stopped band of 3.5‐4.95 GHz at OFF‐state. Therefore, the proposed antenna excels in terms of geometry's simplicity, compactness, near omnidirectional pattern, high efficiency as well as band‐notched configurability.
Design of a MMIC low‐noise amplifier in industrial gallium arsenide technology for E‐band 5G transceivers
Authors: Ciccognani Walter , Colangeli Sergio , Longhi Patrick Ettore , Limiti Ernesto
Published: November 2018

The technology, design procedure and measurements of an E‐band (71‐86 GHz) high performance gallium arsenide (GaAs) low‐noise amplifier (LNA) are presented. The latter provides a gain in excess of 20 dB, an average in‐band noise figure (NF) of 2.3 dB, absorbing 60 mW DC bias power. A European space‐qualified technology (OMMIC's GaAs 70 nm process) has been selected to demonstrate the feasibility of employing the proposed LNA for production‐ready wireless backhaul point‐to‐point communication systems. A possible installation scenario has been depicted, in order to verify the maximum distance at which TX and RX antennas can be placed and employing the proposed LNA as first amplifying stage of the receiver chain.
A dual‐band circularly polarized planar monopole antenna for Wireless Local Area Network/Worldwide Interoperability for Microwave Access applications
Authors: Yang Dong , Zhai Huiqing , Xue Kun , Xi Lei , Wu Xinhua , Li Yinhu
Published: November 2018

In this letter, a new dual‐band circularly polarized (CP) planar monopole antenna is proposed. Simply by embedding an asymmetrical T‐shaped strip into the arc‐shaped feedline, dual‐band operation and CP radiation can be obtained. Furthermore, adding an inverted‐L‐shaped strip to the previous designing, the axial ratio bandwidths (ARBWs) can be greatly improved. After fabricating and then testing, the measured results indicate that the impedance bandwidths (IBWs) below 10‐dB can reach 240 MHz (2.39‐2.63 GHz) and 2.73 GHz (3.85‐6.58 GHz), and the 3‐dB ARBW can cover 260 MHz (2.26‐2.52 GHz) and 2.48 GHz (3.9‐6.38 GHz). The designed antenna can be applied to the WLAN (2.4/5.2/5.8‐GHz) and WiMax (5.5 GHz) multi‐function and multi‐mode communication systems felicitously.
Correction of magnetic field inhomogeneity effects for fast quantitative susceptibility mapping
Authors: Ngo Giang‐Chau , Bilgic Berkin , Gagoski Borjan A. , Sutton Bradley P.
Published: November 2018

Purpose

Quantitative susceptibility mapping (QSM) provides information about tissue composition and organization. However, current acquisition methods can be quite time consuming, limiting the use of QSM in studies and in monitoring dynamic events. In this work, time efficient spiral acquisitions are combined with a model‐based image reconstruction approach. Magnetic field inhomogeneity artifacts are corrected to obtain full brain susceptibility maps.

Methods

Magnetic field maps, capturing the magnetic field inhomogeneity distribution due to non‐tissue sources (background field), were estimated from a calibration scan. Tissue phase information present in the background field maps was identified using variable spherical mean value filtering and removed from the estimated field maps. The resulting background field maps were then used in the image reconstruction to correct the magnetic field inhomogeneity artifacts. Images were acquired on a 3 T system with a 3D spiral‐in acquisition based on a rotated stack of spirals. For comparison, standard gradient echo images were also acquired. Susceptibility maps were obtained for both acquisitions using a dipole inversion algorithm based on a compressed sensing compensated formulation with wavelet and total variation penalties.

Results

Susceptibility maps obtained with the spiral acquisition and the model‐based reconstruction agree with the ones obtained with the spin‐warp gradient echo acquisition. Using the 3D spiral acquisition, full brain susceptibility maps at the resolution of 1 mm isotropic are obtained in 23 s

Conclusions

Image distortions and blurring due to magnetic field inhomogeneity are removed while maintaining tissue magnetic susceptibility information, resulting in QSM maps in much shorter acquisition time.
3D reconstruction of MR‐visible Fe3O4‐mesh implants: Pelvic mesh measurement techniques and preliminary findings
Authors: Brocker Kerstin A. , Mokry Theresa , Alt Céline D. , Kauczor Hans‐Ulrich , Lenz Florian , Sohn Christof , DeLancey John O. , Chen Luyun
Published: November 2018

Aims

To develop MR‐based measurement technique to evaluate the postoperative dimension and location of implanted magnetic resonance (MR)‐visible meshes.

Methods

This technique development study reports findings of six patients (A‐F) with cystoceles treated with anterior vaginal MR‐visible Fe3O4‐polypropylene implants. Implanted meshes were reconstructed from 3 months and/or 1 year postsurgical MR‐images using 3D Slicer®. Measurements including mesh length, distance to the ischial spines, pudendal, and obturator neurovascular bundles and urethra were obtained using software Rhino® and a custom Matlab® program. The range of implanted mesh length and their placements were reported and compared with mesh design and implantation recommendations. With the anterior/posterior‐mesh‐segment‐ratio mesh shrinkage localization was evaluated.

Results

Examinations were possible for patients A‐D 3 months and for A, C, E, and F 1 year postsurgical. The mesh was at least 40% shorter in all patients 3 months and/or 1 year postoperatively. A, B showed shrinkage in the anterior segment, D, E in the posterior segment (Patients C, F not applicable due to intraoperative mesh trimming). Patient E presented pain in the area of mesh shrinkage. In Patient C posterior mesh fixations were placed in the iliococcygeal muscle rather than sacrospinous ligaments. Arm placement less than 20 mm from the pudendal neurovascular bundles was seen in all cases. The portion of the urethra having mesh underneath it ranged from 19% to 55%.

Conclusions

MRI‐based measurement techniques have been developed to quantify implanted mesh location and dimension. Mesh placement variations possibly correlating with postoperative complications can be illustrated.
How does a board of directors influence within‐ and cross‐sector nonprofit collaboration?
Authors: Ihm Jennifer , Shumate Michelle
Published: November 2018

Board members play a significant, yet largely unexamined, role in nonprofit collaboration. Processes, such as finding prospective partners, creating common ground with a partner, and establishing appropriate collaborative governance implicate nonprofit board members. In contrast to the scholarship of the role of interlocking directorates as potential networks for nonprofit collaboration, this paper examines the role of board members' social and human capital on nonprofit collaboration with other nonprofits, businesses, and government agencies. Drawing on online survey data from 636 nonprofit organizations, this paper finds that board social capital—but not board human capital—is positively related to the presence and number of within‐sector and cross‐sector nonprofit collaboration. However, board human capital enhances nonprofit‐government collaboration, when board social capital is also high. The results provide a novel perspective in nonprofit collaboration and board management research.
A novel method to prepare homogeneous biocompatible graphene‐based PDMS composites with enhanced mechanical, thermal and antibacterial properties
Authors: Hu Xiaodong , Qian Wei , Li Xiaochong , Fei Guoxia , Luo Gaoxing , Wang Zhanhua , Xia Hesheng
Published: November 2018

A negative pressure assisted mixing method was applied to prepare homogeneous graphene‐based polydimethylsiloxane (PDMS) composite. The problem of graphene agglomeration in polymer matrix was well overcome by using the graphene microsphere aerogels. They possess unique porous structure and excellent adsorption capacity, enabling the PDMS solution can uniformly fill into the reduced graphene oxide aerogel microspheres (rGOAMs) or GO aerogel microspheres (GOAMs) under reduced pressure. Raw reduced graphene oxide (rGO) and graphene oxide (GO) were added into PDMS by a simple ultrasonic assisted mixing method as a comparison. rGOAMs‐PDMS and GOAMs‐PDMS composites displayed higher tensile strength, Young's modulus and storage modulus than rGO–PDMS and GO–PDMS composites. In addition, the thermal stability of graphene‐based PDMS composites was also significantly improved. Finally, rGOAMs‐PDMS and GOAMs‐PDMS composites performed much better antibacterial activity than that of rGO‐PDMS and GO‐PDMS composites, which demonstrated that this kind of graphene‐based PDMS composites could display a great potential application in biomedical field. POLYM. COMPOS., 40:E1397–E1406, 2019. © 2018 Society of Plastics Engineers
Effect of filler treatments on the crystallization, mechanical properties, morphologies and heat resistance of Polypropylene/phlogopite composites
Authors: Cai Longlong , Dou Qiang
Published: November 2018

Phlogopite was treated with pimelic acid (PA) and PA/Ca(OH)2 in ethanol solution by ball milling, separately. The particle size of the phlogopite decreased after the wet grinding, and β‐nucleating agents (magnesium pimelate and calcium pimelate) were produced after the treatments. Polypropylene/phlogopite composites were prepared in a twin screw extruder. The melt and crystallization behaviors, mechanical properties, morphologies, heat resistance, and processing properties of the composites were characterized. Many β crystals appear and the spherulitic sizes decrease obviously with the addition of the treated phlogopites. When compared with the untreated phlogopite composites, the tensile strength, flexural strength, and Izod notched impact strength of the treated phlogopite composites improve significantly. The mechanical properties of PA/Ca(OH)2‐treated phlogopite composites are the best. The preferential orientation of the phlogopite flakes, numerous small β spherulites and enhanced interfacial adhesion contribute to the improved toughness of the composites. The heat deflection temperatures, shrinkages and densities of the treated phlogopite composites are greater than those of the untreated phlogopite composites. POLYM. COMPOS., 40:E795–E810, 2019. © 2018 Society of Plastics Engineers
Poly(styrene/pentafluorostyrene)‐block‐poly(vinyl alcohol/vinylpyrrolidone) amphiphilic block copolymers for kinetic gas hydrate inhibitors: Synthesis, micellization behavior, and methane hydrate kinetic inhibition
Authors: Rajput Faraz , Colantuoni Antonio , Bayahya Salim , Dhane Riadh , Servio Phillip , Maric Milan
Published: November 2018

Amphiphilic block copolymers of short poly(styrene) (PS) or poly(2,3,4,5,6‐pentafluorostyrene) (PPFS) segments with comparatively longer poly(vinyl acetate) or poly(vinylpyrrolidone) (PVP) segments are synthesized using a 2‐cyanopropan‐2‐yl N‐methyl‐N‐(pyridin‐4‐yl)dithiocarbamate switchable reversible addition–fragmentation chain transfer (RAFT) agent toward application as kinetic gas hydrate inhibitors (KHIs). Polymerization conditions are optimized to provide water‐soluble block copolymers by first polymerizing more activated monomers such as S and PFS to form a defined macro chain‐transfer agent (linear degree of polymerization with conversion, comparatively low dispersity) followed by chain extensions with less activated monomers VAc or VP by switching to the deprotonated form of the RAFT agent. The critical micelle concentrations of these amphiphilic block copolymers (after VAc unit hydrolysis to vinyl alcohol units) are measured using zeta surface potential measurements to estimate physical behavior once mixed with the hydrates. A PS‐poly(vinyl alcohol) block copolymer improved inhibition to 49% compared to the pure methane–water system with no KHIs. This inhibition was further reduced by 27% by substituting the PS with a more hydrophobic PPFS. A block copolymer of PS–PVP exhibited 20% greater inhibition than the PVP homopolymer and substituting PS with a more hydrophobic PPFS resulted in a 35% further decreased in methane KHI. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2445–2457, 56, 2445–2457
Progress Toward Diamond Power Field‐Effect Transistors
Authors: Geis Michael W. , Wade Travis C. , Wuorio Charles H. , Fedynyshyn Theodore H. , Duncan Bradley , Plaut Maxwell E. , Varghese Joseph O. , Warnock Shireen M. , Vitale Steven A. , Hollis Mark A.
Published: November 2018

Diamond's properties (highest thermal conductivity, high hole & electron mobilities, & high electric breakdown field) predict that diamond field‐effect transistors (FETs) will have superior high‐power high‐frequency performance over FETs formed in other semiconductors. The development of diamond FETs is limited by a lack of quality substrates & the high ionization energy of the primary dopant, boron (B). This high ionization energy results in a resistance too high for FETs. Fortunately, recent developments are addressing these shortcomings. Single‐crystal diamond substrates ≈4 inches have been demonstrated. Further, two approaches address the dopant issue. When the surface of diamond is terminated in H, a surface p‐type conductive layer forms. FETs made using this layer demonstrate competitive high‐frequency performance, though manufacturability of this type of device has yet to be worked out. The second solution to doping uses delta doping by B. A thin <2‐nm layer doped with B at >1020 cm−3 is sandwiched within undoped diamond. This structure mitigates B's high ionization energy by producing an acceptor subband with ≈100% of the B is ionized. Recent reports of delta‐doped diamond have channel resistances suitable for device applications. This article reviews the state of the art for FET and substrate development.
Local Stiffness Effect on Ferromagnetic Response of Nanostructure Arrays in Stretchable Systems
Authors: Challab Nabil , Zighem Fatih , Faurie Damien , Haboussi Mohamed , Belmeguenai Mohamed , Lupo Pierpaolo , Adeyeye Adekunle O.
Published: November 2018

The control of magnetoelastic effects in magnetic media, their improvement or even their minimization according to the intended applications is a current problem. In this work, the effect of the elastic strain on the magnetic properties of Ni60Fe40 continuous films and nanowires deposited on Kapton® substrates has been investigated. For this purpose, piezoactuation mechanical tests are performed in situ with ferromagnetic resonance measurements. It has been observed that the continuous thin film and the array of nanowires exhibit distinct behaviors in the presence of an elastic strain field. Precisely, the induced magnetoelastic anisotropy is much less pronounced in the case of nanowires. This difference in behavior has been explained/investigated based on finite element simulations. These latter revealed that the average strain transmitted from flexible substrate to magnetic medium is less important in the case of nanowires compared to continuous film. This lack of strain transfer/transmission is related to the relative amount of free surface of the nanostructures combined with a strong mechanical contrast between Ni60Fe40 and Kapton (viz., a deposit relatively much more stiffer than the substrate). This important effect can be exploited in the future by controlling and optimizing geometries of nanostructures.
Micro‐unmanned aerial vehicle‐based volcano observation system for debris flow evacuation warning
Authors: Nagatani Keiji , Kiribayashi Seiga , Yajima Ryosuke , Hada Yasushi , Izu Tomoaki , Zeniya Akira , Kanai Hiromichi , Kanasaki Hiroyuki , Minagawa Jun , Moriyama Yuji
Published: November 2018

When a volcano erupts, molten rocks, ash, pyroclastic flow, and debris flow can cause disasters. Debris flow is responsible for enormous damage across large areas. This makes debris flow simulations a crucial means of determining whether to issue an evacuation warning for area residents. For safety purposes, restricted areas are designated around volcanos during eruptions, making it difficult to gather information (such as the amount and permeability of ash) required for precise debris flow simulations. An unmanned observation system, intended for use in such restricted areas, was developed to address this issue. The proposed system is based on a multirotor micro‐unmanned aerial vehicle (MUAV) that transports cameras, small devices to measure target environments, and a small robot to active volcanic areas. Several field tests were performed around active volcanoes for validation and system improvement. This study investigates five unmanned systems with field tests. The first one is an autonomous flight to collect three‐dimensional (3D) terrain information. The MUAV conducted the long flight at Mt. Unzen‐Fugen and evaluated the accuracy and calculation time of the developed 3D terrain model. The second one is a drop‐down‐type ash‐depth measurement scale. The scales were deployed at Mt. Unzen‐Fugen and confirmed its function. The third system is a soil‐sampling device to estimate permeability. The device is hung from the MUAV by a long tether and collects soil and gravels directly with two rollers, while the MUAV is hovering. Indoor experiments were conducted to evaluate the performance of the device, and field experiments were conducted to confirm the validation of the system in different volcanic environments. The fourth system is an unmanned surface flow measurement device to estimate permeability. The device carries a water balloon and breaks it when it lands on the ground. By observing water flow with mounted cameras, qualitative permeability can be estimated. Initial experiments were conducted at Mt. Unzen‐Fugen to confirm its function. The fifth system is a small ground vehicle with a rainfall sensor deployed by an MUAV. The MUAV carries a capturing net suspended from it and delivers and retrieves the ground vehicle, while it is hovering. Field experiments were conducted at Mt. Asama and Mt. Unzen‐Fugen to validate the function of the system. Data obtained by these systems can contribute to the improvement of debris flow simulations developed in the project. In this paper, the above systems and experiments to evaluate them are introduced, and debris flow simulation results are demonstrated to prove the effectiveness of the data obtained by the proposed systems. Each field‐test section includes a discussion of the lessons learned.
Synthetic mRNAs Drive Highly Efficient iPS Cell Differentiation to Dopaminergic Neurons
Authors: Xue Yingchao , Zhan Xiping , Sun Shisheng , Karuppagounder Senthilkumar S. , Xia Shuli , Dawson Valina L. , Dawson Ted M. , Laterra John , Zhang Jianmin , Ying Mingyao
Published: November 2018

Proneural transcription factors (TFs) drive highly efficient differentiation of pluripotent stem cells to lineage-specific neurons. However, current strategies mainly rely on genome-integrating viruses. Here, we used synthetic mRNAs coding two proneural TFs (Atoh1 and Ngn2) to differentiate induced pluripotent stem cells (iPSCs) into midbrain dopaminergic (mDA) neurons. mRNAs coding Atoh1 and Ngn2 with defined phosphosite modifications led to higher and more stable protein expression, and induced more efficient neuron conversion, as compared to mRNAs coding wild-type proteins. Using these two modified mRNAs with morphogens, we established a 5-day protocol that can rapidly generate mDA neurons with >90% purity from normal and Parkinson’s disease iPSCs. After in vitro maturation, these mRNA-induced mDA (miDA) neurons recapitulate key biochemical and electrophysiological features of primary mDA neurons and can provide high-content neuron cultures for drug discovery. Proteomic analysis of Atoh1-binding proteins identified the nonmuscle myosin II (NM-II) complex as a new binding partner of nuclear Atoh1. The NM-II complex, commonly known as an ATP-dependent molecular motor, binds more strongly to phosphosite-modified Atoh1 than the wild type. Blebbistatin, an NM-II complex antagonist, and bradykinin, an NM-II complex agonist, inhibited and promoted, respectively, the transcriptional activity of Atoh1 and the efficiency of miDA neuron generation. These findings established the first mRNA-driven strategy for efficient iPSC differentiation to mDA neurons. We further identified the NM-II complex as a positive modulator of Atoh1-driven neuron differentiation. The methodology described here will facilitate the development of mRNA-driven differentiation strategies for generating iPSC-derived progenies widely applicable to disease modeling and cell replacement therapy. Stem Cells Translational Medicine  2019;8:112&12
Enhancing the Optical Behavior of Glass Surface by Creation of Microstructures in Single‐Step Hydrothermal Wet Etching
Authors: Duraisamy Sivagami , Priyadarshini B. Geetha
Published: November 2018

Recent progress in third generation solar cells has lead to significant improvement in device efficiency at laboratory conditions. Glass as a substrate plays a major role in superstrate configuration where maximum light is directed towards active layer which increases photo‐carrier generation. In this work, we focus on improving the glass transmittance by creating microstructures using simple, low cost and environmental friendly technique of hydrothermal wet etching. The glass etching was performed by ultrapure water as etchant. The influence of etching parameters viz., temperature (90, 120, 150, 180 and 210 °C) and time (1, 5, 10 and 15 hrs) on optical transmittance, microstructure, and surface roughness has been systematically studied. At optimal etching conditions, an increase in transmittance up to 93.5% in the range of 375–820 nm was observed in comparison to un‐etched glass. Preferential leaching of Na+ is found to be more pronounced phenomena at optimal condition leading to improvement in optical transmittance which is explained by glass‐water interaction. Based on the proposed mechanism, hydrothermal etching of glass with water enhances the light trapping in broad wavelength and can be used as cover glass in superstrate solar cells comprised of tunable band gaps. The silicon solar cell covered with optimized etched glass showed a relative increase of ∼2.2% in power conversion efficiency as compared to a solar cell covered with an un‐etched glass.
Ni Prussian Blue Analogue/Mesoporous Carbon Composite as Electrode Material for Aqueous K‐Ion Energy Storage: Effect of Carbon‐Framework Interaction on Its Electrochemical Behavior
Authors: Vázquez‐Samperio Juvencio , Sánchez‐Padilla N. M. , Acevedo‐Peña Próspero , Cano Arely , Nava Noel , Morales‐Acosta D. , Oliver‐Tolentino Miguel
Published: November 2018

This study evaluates the interaction of mesoporous carbon (MC) and nitrogen doped mesoporous carbon (NMC) with Nickel prussian blue analogues (Ni‐PBA) and its effect on electrochemical properties and energy storage. The Raman, IR, Mossbauer and XPS results reveal that MC‐NiPBA composite exhibited a large modification to covalent character of carbon and an increase in defects of carbonaceous material. This latter is associated with the oxidation of carbon sites and reduction of iron in hexacyanoferrate during composite synthesis, which increase the charge subtraction in Fe (Low Spin) through CN ligand, due to sp‐d hybridization between nickel and carbon structure. Electrochemical impedance spectroscopy characterization showed that the interaction between MC and NiPBA decreases the paste resistance and improves the chemical capacitance of the material, whereas, the apparent diffusion coefficient for K‐ion in Ni‐PBA is not affected by the presence of mesoporous carbon. The cyclic voltammetry and galvanostatic characterization confirm the enhancement of MC‐NiPBA capacitance during charge/discharge process due to their synergetic interaction. However, the donor/acceptor characteristics of nitrogen modify the orbital hybridization in doped carbon, inhibiting the carbon‐framework interaction.
Synthesis of Cu‐BTC Metal‐Organic Framework by Ultrasonic Wave‐Assisted Ball Milling with Enhanced Congo Red Removal Property
Authors: Luo Yun , Chen Ding , Wei Fuhua , Liang Zhao
Published: November 2018

Cu‐BTC (BTC=1,3,5‐benzenetricarboxylate) metal‐organic framework (MOF) with truncated octahedral morphology was synthesized by ultrasonic wave‐assisted ball milling at room temperature and atmospheric pressure. It was characterized by X‐ray powder diffraction (XRD), thermo‐gravimetric analysis (TGA), nitrogen adsorption and scanning electron microscopy (SEM). The parameters such as synthetic method, reaction time and raw material molar ratio (H3BTC: Cu2+) were studied to tune the growth of Cu‐BTC crystals. Adsorption of Congo red (CR) on Cu‐BTC was studied in respect of adsorption kinetics, isotherm and thermodynamics. Pseudo‐second‐order kinetics and Langmuir adsorption isotherm model were matched well with the adsorption process. The maximum adsorption capacity (Qm) was 884.96 mg/g, attributed to the interfacial effect in (100) facets. Thermodynamic parameters confirmed that the adsorption was a spontaneous and endothermic process, and entropy effect was the driving force for adsorption process.
A Highly Sensitive Determination of Parathion Pesticide by Solid‐Phase Extraction on a Silicon Carbide Nanoparticles Modified Electrode
Authors: Bakytkarim Yrysgul , Tursynbolat Satar , Zeng Qiang , Huang Jianzhi , Wang Lishi
Published: November 2018

This work reports a highly sensitive electrochemical sensor for the direct detection of pesticides. An electrode modification of silicon carbide nanoparticles has the function of pesticide pre‐concentration by solid‐phase extraction, thus improving the detection sensitivity and simplifying the process of operations. Electrochemical detection of parathion was investigated via cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS), respectively. Under the optimized experimental conditions, the anodic peak currents of parathion by SWV are proportional to the concentrations of parathion in the linearity of Ip (μA)= 0.00325 C (ng/ml) + 0.2162 (R2=0.9985) ranging from 1×10−9 to 1×10−5 ng/ml with a detection limit of 5×10−10 ng/ml (S/N=3). The sensor also exhibits good reproducibility and stability, and has been successfully used for the determination of parathion in real water samples with the recoveries between 99.8% and 101.2%.
Mechanochemical‐ (Hand‐Grinding‐) Assisted Domino Synthesis of Fused Pyran‐Spirooxindoles under Solvent‐ and Catalyst‐Free Condition
Authors: Hussen Abdulkadir Shube , Pandey Amar Prakash , Sharma Anuj
Published: November 2018

An efficient and green strategy is developed to synthesize 2‐amino‐2‐oxospiro [indoline‐3, 4′‐pyran]‐3′‐carbonitriles. The method encompasses a domino multicomponent reaction using isatin or acetanaphthelenequinone, malononitrile or ethylcyanoacetate and enolizable 1, 3‐dicarbonyl compounds without any promoter and catalyst in one pot through hand grinding in excellent yields within minutes.
Development of Hierarchical Porous MOF‐Based Catalyst of UiO‐66(Hf) and Its Application for 5‐Hydroxymethylfurfural Production from Cellulose
Authors: Zhao Jiaojiao , Zhang Yunlei , Wang Kai , Yan Changhao , Da Zulin , Li Chunxiang , Yan Yongsheng
Published: November 2018

Due to its widely green and sustainable properties, cellulose is identified as a green and sustainable alternative for the preparation of valuable biofuels and chemicals. In this study, Poly‐Pickering HIPEs (PHs) was synthesized as the precursor by using Pickering high internal phase emulsion (HIPE) as templates and PHs‐SO3H was prepared after sulfonation treatment. We chemically grafted UiO‐66(Hf)‐type MOFs onto PHs‐SO3H in order to synthesize a novel catalyst for the transformation of cellulose into 5‐HMF, which made clear that HMF yield was improved in the presence of the catalyst. What's more, the 5‐HMF yield of 49.6% was obtained under the optimal conditions of 50 mg cellulose, 30 mg catalyst, 60 min of reaction time and 120 °C of reaction temperature. The catalyst is recyclable four cycles without crucial loss of catalytic activity.
One‐step Modification of Active Sites and Support in Ni/Al2O3 Catalyst for Hydrodeoxygenation of Lignin‐derived Diphenyl Ether
Authors: Yang Kaixuan , Chen Xiao , Lafaye Gwendoline , Especel Catherine , Epron Florence , Liang Changhai
Published: November 2018

A bifunctional Ni2Si/SiO2‐Al2O3 catalyst was prepared by one‐step chemical vapor deposition (CVD), and used for hydrode‐oxygenation (HDO) of diphenyl ether (DPE). During the one‐step CVD process, metallic Ni species as the HDO active sites were isolated by intermetallic modification of Si atoms and partial electron transferred from Ni to Si, as inferred by XRD, XPS, and theoretical calculation. Furthermore, the characterization results revealed that the acidity and structure of Al2O3 were tuned due to the formation of Al‐O−Si bonds. Consequently, compared with Ni/Al2O3 catalyst, the Ni2Si/SiO2‐Al2O3 catalyst showed a higher benzene selectivity (60% vs 47%), O‐free products selectivity at the similar conversion of DPE, and high stability for the HDO of DPE. This work provides insight for design of bifunctional catalysts with specific catalytic properties by one‐step CVD method.
In‐situ Glycine Sensor Development Based ZnO/Al2O3/Cr2O3 Nanoparticles
Authors: Alam M. M. , Asiri Abdullah M. , Uddin M. T. , Islam M. A. , Rahman Mohammed M.
Published: November 2018

Initially, low‐dimensional ternary nanoparticles of ZnO/Al2O3/Cr2O3 were synthesized using reliable solvothermal process and successfully implemented to fabricate enzyme‐less selective glycine (Gly) sensor. The calibration curve was plotted from the linear relation of current versus concentration of glycine. By using the slope of resultant calibration curve, the sensitivity (2.09*102 μAμM−1cm−2) of Gly sensor was estimated by considering the active surface area of fabricated sensor probe. The proposed enzyme‐free Gly biosensor was found linear over large concentration range of 0.1 nM ∼ 1.0 μM, known as linear dynamic range (LDR). The detection limit (82.25±4.11 pM) was calculated at signal to noise ratio of 3 from the calibration curve. The proposed enzyme‐less Gly sensor was exhibited good reproducibility, long‐term stability and efficiency to detect Gly in real biological samples by electrochemical approach. Thus, this novel research methodology might be a good technique for the development of enzyme‐less sensor using ternary metal oxide nanoparticles onto GCE for the biomedical applications.
Biphenyl 3‐ and 4‐ mono and 4, 4′‐dicarbaldehyde as Electrophiles and Unusual Michael Acceptors in the Baylis‐Hillman Reaction: Synthesis of Functionalized Biphenyl Derivatives
Authors: Athira Mohanakumaran , Meerakrishna Ramakrishnan Suseela , Shanmugam Ponnusamy
Published: November 2018

The Morita‐Baylis‐Hillman (MBH) reaction of biphenyl 3‐ and 4‐ mono aldehydes and 4, 4′‐dicarbaldehyde as electrophiles and a number of unexplored activated alkenes afforded highly functionalized biphenyl derivatives in excellent yield. Synthetic transformations of mono and bis MBH adducts thus obtained have been demonstrated by isomerization of MBH adducts with different nucleophiles, Friedel‐Crafts arylation reaction of bromo isomerized biphenyl adducts, Eglinton coupling of biphenyl propargyl MBH adduct derivative and [3+2]‐ azomethine ylide cycloaddition of methyl acrylate derived biphenyl aldehydes afforded highly functionalized arylated and heterocyclic derivatives in very good yield.
Co‐Al Hydrotalcites: Highly Active Catalysts for the One‐Pot Conversion of Fructose to 2,5‐Diformylfuran
Authors: Raut Amol B. , Bhanage Bhalchandra M.
Published: November 2018

In this work, a series of Co−Al hydrotalcites were synthesized in the molar ratio of 1:1(cat‐3), 2:1(cat‐4), 3:1(cat‐5). These synthesized Co−Al hydrotalcites were characterized by different characterization techniques such as XRD, XPS, FT‐IR, SEM, EDX, TGA, and N2 physical adsorption. The catalytic properties of the prepared Co−Al hydrotalcites in different molar ratio were investigated for the dehydration of fructose to 5‐hydroxymethylfurfural (HMF), and selective oxidation of the HMF into 2,5‐diformylfuran (DFF). The complete conversion of HMF led to 95% yield of DFF at 120 °C under 3 bar oxygen pressure in dimethyl sulfoxide (DMSO) for 6 h. DFF in the yield of 87% with 100% conversion of fructose could be achieved in a one pot and two‐step reaction using Co−Al calacite in ratio of 2:1(cat‐4). A 77% yield of DFF was obtained in one‐pot and one‐step reaction using the same hydrotalcite catalyst. A DFF yield of 59% was achieved in a one pot and one‐step reaction using air as oxidant. After completion of the reaction, the catalyst can be separate very easily and can be reused up to four times without any significant loss in its catalytic activity.
A New One‐Pot Synthesis of Tetrasubstituted Pyrazines by the Ti‐Catalyzed Reaction of Aromatic and Benzyl‐Substituted Nitriles with EtAlCl2
Authors: Khafizova Leila O. , Shaibakova Mariya G. , Dzhemilev Usein M.
Published: November 2018

A new one‐pot catalytic synthesis of tetrasubstituted pyrazines based on reaction of nitriles with EtAlCl2 in the presence of metallic Mg and the Cp2TiCl2 catalyst with good yields (60‐90%) has been developed. The probable mechanistic scheme for the formation of substituted pyrazines is proposed.
Strategic responses to shocks: Comparative adjustment costs, transaction costs, and opportunity costs
Authors: Argyres Nicholas , Mahoney Joseph T. , Nickerson Jackson
Published: November 2018

Research Summary

Shocks, whether they derive from shifts in demand, supply, regulation, or innovation, can create the need for competitive repositioning by industry participants when they disrupt established sources of competitive advantage. Such situations can therefore create a canonical strategic problem: whether, where, and how to (re‐)position following an industry shock. In this paper, we explore the role of comparative adjustment costs in determining competitive advantage in dynamic environments. In so doing, we synthesize contributions from Penrose, Porter, and Williamson to conceptualize the relationship between adjustment costs and related concepts such as resources/capabilities, dynamic capabilities, transaction costs, and opportunity costs.

Managerial Summary

Whether, where, and how should leaders reposition their firms in response to industry shocks? This paper develops a framework to guide leaders charged with making these decisions. The framework emphasizes that firms facing an industry shock must: (a) assess their firm's cost and time to move to each new position, and compare that cost and time to rivals' costs and time to move to those same positions; (b) compare the cost of delaying repositioning (such as forfeiting first mover advantage) to the profits from remaining in its original position, and (c) consider that, in order to speed repositioning, the efficient choice may be to temporarily accept certain hazards from outsourcing, and later integrate to eliminate those hazards. We illustrate the framework using an example from the smartphone industry.
Modeling of the Effect of the Gas Flow Rate on the Fluid Flow and Open‐Eye Formation in a Water Model of a Steelmaking Ladle
Authors: Ramasetti Eshwar Kumar , Visuri Ville‐Valtteri , Sulasalmi Petri , Mattila Riku , Fabritius Timo
Published: November 2018

In ladle metallurgy of steelmaking, the role of gas injection into the metal bath is been studied to a great extent as it improves the quality of steel. The size of the open‐eye is associated with higher emulsification of top slag, which intensifies metal–slag reactions, and information about the position and size of the open‐eye is important for effective alloying practice. Moreover, the open‐eye has an effect on the energy balance since it increases heat losses. In this work, experimental measurements and numerical simulations are performed to study the effect gas flow rate on the formation of the open‐eye in a steelmaking ladle. A one‐fifth scale water model is constructed for studying gas injection with single and dual plug configurations. For the numerical modeling, the Multiphase Volume of Fluid (VOF) model is used for simulating the system including the behavior of the slag layer. The physical modeling results show that the open‐eye area changes from 9.22 to 198.34 cm2 when the gas flow rate varies from 0.75 to 15 SLM using a single plug. The effect of the number of plugs on the open‐eye area for the same range of flow rates mentioned above is also studied. The two open‐eye areas generated due to the gas injected through the dual plugs change from 37.59 to 231.1 cm2 when the gas flow rate is increased from 0.75 to 7.5 SLM for each plug in the physical modeling. The numerical simulation results of the open‐eye area are found to be in good agreement with the experimental data obtained from the water model. During the gas stirring process, the slag layer is deformed such that the thickness of the slag becomes thick near to the wall and thin near the slag eye at high gas flow rates. In dual plug system, the two open‐eyes tends to merge and form a huge open‐eye at high flow rates that suits for better alloying purposes. The high‐flow velocity near the surface, which could damage the ladle refractory, tends to be reduced in dual plug system when compared to single plug system.
Template‐Synthesized Vertical Needle Array as Injection Platform for Microalgae
Authors: Mukaibo Hitomi
Published: November 2018

Increasing numbers of studies in the past few decades have demonstrated vertically‐oriented nanoneedles arrays (NNAs) as innovative tools to interrogate and manipulate biological cells, where the needles are inserted into the cells as functional probes for high‐throughput detection and biomolecule delivery. However, majority of these studies use mammalian cells: leaving NNA application to plant cells still in its infancy and largely unexplored. This paper highlights our contributions in exploring the utility of NNAs to microalgae – a diverse group of aquatic, photosynthetic organisms studied intensively as bio‐factories for producing high‐value‐added products such as fuels and pharmaceuticals. Microalgal strain development processes have long suffered from the hard cell wall that surrounds the cell and inhibits delivery of foreign materials into the cell. Conically‐shaped, metallic NNAs were developed with template synthesis that successfully penetrate through the cell wall barrier and achieve material injection – using the widely studied model microalga, Chlamydomonas reinhardtii. Earlier works from mammalian cells are introduced and discussed to clarify the framework established in this field, while recent studies of both mammalian and microalgal cells are also referenced to examine the trends, challenges, and future perspectives of NNA application to microalgae.
LncRNA‐Jak3:Jak3 coexpressed pattern regulates monosodium urate crystal‐induced osteoclast differentiation through Nfatc1/Ctsk expression
Authors: Lee Chi‐Pin , Huang Yu‐Nan , Nithiyanantham Srinivasan , Huang Chung‐Ming , Ko Ying‐Chin
Published: November 2018

LncRNA transcripts have been emerged as gene regulators through transcriptional and posttranscriptional regulation. Monosodium urate monohydrate (MSU) elicits inflammatory response and a critical regulator of bone erosion in gout. The aim of this study is to clarify the pro‐osteogenic role of LncRNA in MSU‐induced osteoclast differentiation. We performed microarray analysis to identify stage specific expressions of LncRNA and mRNA during osteoclast differentiation in RAW264.7 cells. Among the 314 pairs of LncRNA‐mRNA coexpressed patterns in the osteoclast lineage, 22 pairs revealed to have inflammatory function. Importantly, LncRNA‐Jak3 and Jak3 co‐expression patterns were significantly upregulated in the osteoclasts. In specific, Jak3 contributes to MSU‐induced osteoclasts differentiation by positively regulating expression of the osteoclast factor, nuclear factor of activated T‐cells 1 (Nfatc1). Mechanistically, LncRNA‐Jak3‐mediated Nfatc1 activation upregulated cathepsin K (Ctsk) expressions. LncRNA‐Jak3 knockdown abolished formation of MSU‐induced mature osteoclasts. In addition, we found that gout patients showed increased levels of LncRNA‐Jak3 in the mononuclear cells. Our data demonstrate that the critical functional role of LncRNA‐Jak3 in osteoclast differentiation via Jak3/Nfatc1/Ctsk axis. Finally, characterization of these regulatory networks is likely to reveal novel drug targets and opportunities for therapeutic intervention in bone erosion.
A perspective on pre‐eclampsia and neurodevelopmental outcomes in the offspring: Does maternal inflammation play a role?
Authors: Maher Gillian M. , McCarthy Fergus P. , McCarthy Cathal M. , Kenny Louise C. , Kearney Patricia M. , Khashan Ali S. , O'Keeffe Gerard W.
Published: November 2018

Pre‐eclampsia is a leading cause of maternal death and maternal and perinatal morbidity. Whilst the clinical manifestations of pre‐eclampsia often occur in late pregnancy, the molecular events leading into the onset of this disease are thought to originate in early pregnancy and result in insufficient placentation. Although the causative molecular basis of pre‐eclampsia remains poorly understood, maternal inflammation is recognised as a core clinical feature. While the adverse effects of pre‐eclampsia on maternal and fetal health in pregnancy is well‐recognised, the long‐term impact of pre‐eclampsia exposure on the risk of autism spectrum disorder (ASD) in exposed offspring is a topic of on‐going debate. In particular, a recent systematic review has reported an association between exposure to pre‐eclampsia and increased risk of ASD, however the molecular basis of this association is unknown. Here we review recent evidence for; 1) maternal inflammation in pre‐eclampsia; 2) epidemiological evidence for alterations in neurodevelopmental outcomes in offspring exposed to pre‐eclampsia; 3) long‐term changes in the brains of offspring exposed to pre‐eclampsia; and 4) how maternal inflammation may lead to altered neurodevelopmental outcomes in pre‐eclampsia exposed offspring. Finally, we discuss the implications of this for the development of future studies in this field.
Boundary streaming by internal waves
Authors: Renaud A. , Venaille A.
Published: November 2018

Damped internal wave beams in stratified fluids have long been known to generate strong mean flows through a mechanism analogous to acoustic streaming. While the role of viscous boundary layers in acoustic streaming has been thoroughly addressed, it remains largely unexplored in the case of internal waves. Here we compute the mean flow generated close to an undulating wall that emits internal waves in a viscous, linearly stratified two-dimensional Boussinesq fluid. Using a quasi-linear approach, we demonstrate that the form of the boundary conditions dramatically impacts the generated boundary streaming. In the no-slip scenario, the early-time Reynolds stress divergence within the viscous boundary layer is much stronger than within the bulk while also driving flow in the opposite direction. Whatever the boundary condition, boundary streaming is however dominated by bulk streaming at larger time. Using a Wentzel–Kramers–Brillouin approach, we investigate the consequences of adding boundary streaming effects to an idealised model of wave–mean flow interactions known to reproduce the salient features of the quasi-biennial oscillation. The presence of wave boundary layers has a quantitative impact on the flow reversals.
Entrepreneurial engagement in a depleted small town: Legitimacy and embeddedness
Authors: Bensemann Jo , Warren Lorraine , Anderson Alistair
Published: November 2018

Our study of entrepreneurial engagement within a depleted New Zealand community contributes to understanding the role of place and legitimacy in entrepreneurial practice. General decline characterised Stanton until a newcomer entrepreneur started several businesses that rejuvenated the town. She became a local economic hero to many stakeholders; but others deployed social narratives of place that drew on different values. Our analysis of interactions shows how perceptions of place legitimise or vilify and we demonstrate how place intercedes upon economically generated legitimacy of entrepreneurial practice. Social constructions of place and notions of embeddedness influenced this entrepreneurial enactment. Conceptually, we challenge ideas about universal legitimacy ensuing from economic entrepreneurial benefits. Our theoretical contribution offers socio-spatial propositions for understanding entrepreneurial legitimacy through place.
Arterial spin labelling and diffusion-weighted magnetic resonance imaging in differentiation of recurrent head and neck cancer from post-radiation changes
Authors: Abdel Razek A A K
Published: November 2018

Objective

To assess arterial spin labelling and diffusion-weighted imaging in the differentiation of recurrent head and neck cancer from post-radiation changes.

Methods

A retrospective study was conducted of 47 patients with head and neck cancer, treated with radiotherapy, who underwent magnetic resonance arterial spin labelling and diffusion-weighted magnetic resonance imaging. Tumour blood flow and apparent diffusion co-efficient of the lesion were calculated.

Results

There was significant difference (p= 0.001) in tumour blood flow between patients with recurrent head and neck cancer (n= 31) (47.37 ± 16.3 ml/100 g/minute) and those with post-radiation changes (n= 16) (18.80 ± 2.9 ml/100 g/minute). The thresholds of tumour blood flow and apparent diffusion co-efficient used for differentiating recurrence from post-radiation changes were more than 24.0 ml/100 g/minute and 1.21 × 10−3mm2/second or less, with area under the curve values of 0.94 and 0.90, and accuracy rates of 88.2 per cent and 88.2 per cent, respectively. The combined tumour blood flow and apparent diffusion co-efficient values used for differentiating recurrence from post-radiation changes had an area under the curve of 0.96 and an accuracy of 90.2 per cent.

Conclusion

Combined tumour blood flow and apparent diffusion co-efficient can differentiate recurrence from post-radiation changes.