bluuebunny/crossref_metadata_2025 huggingface dataset:
Patient Perception of Speech Outcomes: The Relationship Between Clinical Measures and Self-Perception of Speech Function Following Surgical Treatment for Oral Cancer
Authors: Constantinescu Gabriela , Rieger Jana , Winget Marcy , Paulsen Catherine , Seikaly Hadi
Published: March 2017

Purpose

Treatment for oral cancer can result in speech impairments that can have varying impacts on patient quality of life. This study explored the relationship between clinical measures of speech impairment and the perception that patients had of this change in the early stage of recovery.

Method

This was a quasi-experimental 1-group pre–post study design carried out on 10 patients with surgical intervention for oral cancer. Two clinical measures (word intelligibility and consonant phoneme error) and 2 patient-perception measures (Speech Handicap Index total score and Speech Handicap Index patient criteria score) were collected at preoperative and 1-month postoperative appointments.

Results

Qualitative analysis revealed discordance between clinical and patient-perceived measures in 4 of 10 patients. Change in consonant phoneme error and change in word intelligibility were significantly correlated (r= .827). Furthermore, on average, statistically significant relationships were not found between clinical and patient-perceived measures or between the 2 patient-perception measures.

Conclusions

Discordance between clinical and patient-perceived measures was observed in almost half of the sample, indicating that clinical tests did not fully explain the extent of impairment perceived by patients. Speech outcomes should focus on both types of measures, and patient perception outcomes should be carefully considered when recommending speech therapy.
Steady‐state mean‐square deviation analysis of the sign subband adaptive filter
Authors: Shin J. , Yoo J. , Park P.
Published: March 2017

The steady‐state mean‐square deviation (MSD) analysis of the sign subband adaptive filter is proposed. The proposed analysis is derived by the update recursion of the MSD using Price's theorem and chi‐distribution in stationary environments. Experimental results show that the proposed analysis is very close to simulated results not only for white input but also for coloured input signals.
Dual‐mode band‐pass filters made by SU‐8 micromachining technology for terahertz region
Authors: Junlin Wang , Binzhen Zhang , Xin Wang , Junping Duan , Wanjun Wang
Published: March 2017

Two four‐order dual‐mode rectangular waveguide filters centred at 100 GHZ with return loss all better than −19 dB are presented. The filters consist of two cascade resonant cavities suppose TE102/TE301 degenerate modes and three pairs of round corner inductive irises symmetrical with waveguide. Since the introduction of round corner irises and dual‐mode cavities, the filter structures have lower aspect ratio and less resonant cavities, thus the difficulty of fabrication sharply reduced. Single zero exists at the one side of pass‐band because of the same width of two resonant cavities. All the other parameters constant except for the widths of two cavities slightly unequal, two distinct transmission zeros can generate at the same side of pass‐band. UV lithography technology with SU‐8 photo‐resist is used for the fabrication of filters. On the whole, results from measurement are in good agreement with simulation, which fully confirm the validity of design and fabrication methods.
Miniaturised millimetre wave frequency selective surface for atmospheric remote sensing
Authors: Poojali J. , Ray S. , Pesala B. , Krishnamurthy C.V. , Arunachalam K.
Published: March 2017

A miniaturised frequency selective surface (FSS) with λ0/7 × λ0/7 unit cell at the pass band centre frequency is presented for millimetre wave remote sensing. A resonant corner convoluted square ring (CCSR) is loaded with non‐resonant cross dipole (CD) for tri‐band spectral response. Rectangular patches integrated in the CCSR are used to optimise the coupling between the CD and CCSR to reject 50–60 GHz (B1) and 170–195 GHz (B3), and transmit 87–91 GHz (B2). The FSS fabricated on 175 μm thick quartz with 3721 unit cells indicates polarisation and angle stable transmission response.
Labyrinthectomy and Vestibular Neurectomy for Intractable Vertiginous Symptoms
Authors: Alarcón Alfredo , Hidalgo Lourdes , Arévalo Rodrigo , Diaz Marite
Published: March 2017

Introduction Labyrinthectomy and vestibular neurectomy are considered the surgical procedures with the highest possibility of controlling medically untreatable incapacitating vertigo. Ironically, after 100 years of the introduction of both transmastoid labyrinthectomy and vestibular neurectomy, the choice of which procedure to use rests primarily on the evaluation of the hearing and of the surgical morbidity.

Objective To review surgical labyrinthectomy and vestibular neurectomy for the treatment of incapacitating vestibular disorders.

Data Sources PubMed, MD consult and Ovid-SP databases.

Data Synthesis In this review we describe and compare surgical labyrinthectomy and vestibular neurectomy. A contrast between surgical and chemical labyrinthectomy is also examined. Proper candidate selection, success in vertigo control and complication rates are discussed on the basis of a literature review.

Conclusions Vestibular nerve section and labyrinthectomy achieve high and comparable rates of vertigo control. Even though vestibular neurectomy is considered a hearing sparing surgery, since it is an intradural procedure, it carries a greater risk of complications than transmastoid labyrinthectomy. Furthermore, since many patients whose hearing is preserved with vestibular nerve section may ultimately lose that hearing, the long-term value of hearing preservation is not well established. Although the combination of both procedures, in the form of a translabyrinthine vestibular nerve section, is the most certain way to ablate vestibular function for patients with no useful hearing and disabling vertigo, some advocate for transmastoid labyrinthectomy alone, considering that avoiding opening the subarachnoid space minimizes the possible intracranial complications. Chemical labyrinthectomy may be considered a safer alternative, but the risks of hearing loss when hearing preservation is desired are also high.
Telemedicine for gastrointestinal endoscopy: The Endoscopic Club E-conference in the Asia Pacific Region
Authors: Ho Shiaw-Hooi , Rerknimitr Rungsun , Kudo Kuriko , Tomimatsu Shunta , Ahmad Mohamad , Aso Akira , Seo Dong , Goh Khean-Lee , Shimizu Shuji
Published: March 2017

Background and study aims An Endoscopic Club E-conference (ECE) was set up in May 2014 to cater to increased demand for gastrointestinal endoscopy-related teleconferences in the Asia-Pacific region which were traditionally organized by the medical working group (MWG) of Asia-Pacific Advanced Network. This study describes how the ECE meeting was run, examines the group dynamics, outlines feedback and analyzes factors affecting the enthusiasm of participants. It is hoped that the findings here can serve as guidance for future development of other teleconference groups.

Methods The preparation, running of and feedback on the ECE teleconference were evaluated and described. The country’s economic situation, time zone differences, connectivity with a research and education network (REN) and engineering cooperation of each member were recorded and analyzed with regard to their association with participant enthusiasm, which was taken as participation in at least 50 % of the meetings since joining. Associations were calculated using 2-way table with chi-square test to generate odds ratio and P value.

Results To date, ECE members have increased from 7 to 29 (increment of 314 %). Feedback received indicated a high level of satisfaction with program content, audiovisual transmission and ease of technical preparation. Upper gastrointestinal luminal endoscopy-related topics were the most favored program content. Those topics were presented mainly via case studies with a focus on management challenges. Time zone differences of more than 6 hours and poor engineering cooperation were independently associated with inactive participation (P values of 0.04 and 0.001 respectively).

Conclusions Good program content and high-quality audiovisual transmission are keys to the success of an endoscopic medical teleconference. In our analysis, poor engineering cooperation and discordant time zones contributed to inactive participation while connectivity with REN and a country’s economic situation were not significantly associated with participant enthusiasm.
Molecular dynamic simulation study of plasma etching L1 FePt media in embedded mask patterning (EMP) process
Authors: Zhu Jianxin , Quarterman P. , Wang Jian-Ping
Published: March 2017

Plasma etching process of single-crystal L10-FePt media [H. Wang et al., Appl. Phys. Lett. 102(5) (2013)] is studied using molecular dynamic simulation. Embedded-Atom Method [M. S. Daw and M. I. Baskes, Phy. Rev. B 29, 6443 (1984); X. W. Zhou, R. A. Johnson and H. N. G. Wadley, Phy. Rev. B 69, 144113 (2004)] is used to calculate the interatomic potential within atoms in FePt alloy, and ZBL potential [J.F. Ziegler, J. P. Biersack and U. Littmark, “The Stopping and Range of Ions in Matter,” Volume 1, Pergamon,1985] in comparison with conventional Lennard-Jones “12-6” potential is applied to interactions between etching gas ions and metal atoms. It is shown the post-etch structure defects can include amorphized surface layer and lattice interstitial point defects that caused by etchant ions passed through the surface layer. We show that the amorphized or damaged FePt lattice surface layer (or “magnetic dead-layer”) thickness after etching increases with ion energy for Ar ion impacts, but significantly small for He ions at up to 250eV ion energy. However, we showed that He sputtering creates more interstitial defects at lower energy levels and defects are deeper below the surface compared to Ar sputtering. We also calculate the interstitial defect level and depth as dependence on ion energy for both Ar and He ions. Media magnetic property loss due to these defects is also discussed.
Characterization of nanostructure ferrite material on gallium nitride on SiC substrate for millimeter wave integrated circuit
Authors: O’Keefe Brian , Liang Tinghao , Afsar Mohammad N. , Koomson Valencia J.
Published: March 2017

In this paper, for the first time, the characterization of spin-casted thick Barium nano-hexaferrite film on GaN-on-SiC substrate over a broad frequency range of 30-110 GHz is presented. Real and imaginary parts of both permittivity and permeability of the ferrite/polymer film are computed from transmittance data obtained by using a free space quasi-optical millimeter wave spectrometer. The spin-casted composite film shows strong resonance in the Q band, and mixing the powder with polymer slightly shifts the resonance frequency lower compared to pure powder. The high temperature compatibility of GaN substrate enables us to run burn-out tests at temperatures up to 900°C. Significant shortening phenomenon of resonance linewidth after heat treatment was found. Linewidth is reduced from 2.8 kOe to 1.7 kOe. Experiment results show that the aforementioned film is a good candidate in applications of non-reciprocal ferrite devices like isolators, phase shifters, and circulators.
How to enable bulk-like martensitic transformation in epitaxial films
Authors: Wodniok Marius , Teichert Niclas , Helmich Lars , Hütten Andreas
Published: March 2017

The present study is dedicated to the influence of different substrate and buffer layer materials on the martensitic transformation in sputter deposited epitaxial shape memory Heusler alloys. For this, the magnetocaloric Heusler alloy Ni-Co-Mn-Al [N. Teichert et al., Phys. Rev. B 91, 184405 (2015)] is grown on MgO(001), MgAl2O4(001), and MgO(001)/V substrates, which exhibit a lattice misfit to the Ni-Co-Mn-Al between −1.2% and 3.6%. By temperature dependent X-ray diffraction measurements it is shown that the optimum buffer layer for shape memory Heusler films is not one with minimum lattice misfit, but one with minimum Young’s modulus and moderate misfit because an elastic buffer layer can deform during the martensitic transformation of the Heusler layer. Furthermore, epitaxial strain caused by a moderate lattice misfit does not significantly change the martensitic transformation temperatures.
Microscopic evidence of magnetic and structure phase transition in multiferroic spinel FeV2O4
Authors: Myoung Bo Ra , Kim Sam Jin , Lim Jung Tae , Kouh Taejoon , Kim Chul Sung
Published: March 2017

We report the microscopic evidence for magnetic and structural phase transitions in multiferroic spinel FeV2O4 from the hyperfine magnetic interaction. FeV2O4 sample shows three different crystal structures with the phase transitions from tetragonal to orthorhombic structure around 70 K, from orthorhombic to tetragonal structure around 109 K, and from tetragonal to cubic structure around 140 K. Mössbauer spectra of FeV2O4, obtained at various temperatures, were analyzed with severely distorted 8-line below TC, and doublet at TC. Also, the Mössbauer spectra change from doublet to singlet around TJT ≅ 140 K due to the reduction of Jahn-Teller effect. The value of electric quadrupole splitting (ΔEQ) is 3.05 mm/s at 4.2 K, indicating the noncollinear spin structure with strong polarization from the gap energy of 5T2g band, Δ1 ≅ 0. Whereas, there is collinear spin structure between TS ≅ 70 K < T < TC ≅ 109 K, since Δ1 in this temperature range increases from the value when T < TS due to the non-degenerate energy state with commensuration in the collinear state. Also, we have found that large polar angle θ for T < TS suggests the spin of the Fe2+ cations aligns along c-axis with the distortion in the a-b plane, while the small azimuthal angle θ suggest the direction of the spin is within ab-plane for TS < T < TC.
Eddy current loss calculation and thermal analysis of axial-flux permanent magnet couplers
Authors: Zheng Di , Wang Dazhi , Li Shuo , Shi Tongyu , Li Zhao , Yu Linxin
Published: March 2017

A three-dimensional magnetic field analytical model of axial-flux permanent magnet couplers is presented to calculate the eddy current loss, and the prediction of the copper plate temperature under various loads is analyzed. The magnetic field distribution is calculated, and then the eddy current loss is obtained, with the magnetic field analytical model established in cylindrical coordinate. The influence of various loads on eddy current loss is analyzed. Furthermore, a thermal model of axial-flux permanent magnet couplers is established by taking the eddy current loss as the heat source, using the electromagnetic-thermal coupled method. With the help of the thermal model, the influence of various loads on copper plate temperature rise is also analyzed. The calculated results are compared with the results of finite element method and measurement. The comparison results confirm the validity of the magnetic field analytical model and thermal model.
Enhancement of L1 ordering with the c-axis perpendicular to the substrate in FePt alloy film by using an epitaxial cap-layer
Authors: Ohtake Mitsuru , Nakamura Masahiro , Futamoto Masaaki , Kirino Fumiyoshi , Inaba Nobuyuki
Published: March 2017

FePt alloy thin films with cap-layers of MgO or C are prepared on MgO(001) single-crystal substrates by using a two-step method consisting of low-temperature deposition at 200 °C followed by high-temperature annealing at 600 °C. The FePt film thickness is fixed at 10 nm, whereas the cap-layer thickness is varied from 1 to 10 nm. The influences of cap-layer material and cap-layer thickness on the variant structure and the L10 ordering are investigated. Single-crystal FePt(001) films with disordered fcc structure (A1) grow epitaxially on the substrates at 200 °C. Single-crystal MgO(001) cap-layers grow epitaxially on the FePt films, whereas the structure of C cap-layers is amorphous. The phase transformation from A1 to L10 occurs when the films are annealed at 600 °C. The FePt films with MgO cap-layers thicker than 2 nm consist of L10(001) variant with the c-axis perpendicular to the substrate surface, whereas those with C cap-layers involve small volumes of L10(100) and (010) variants with the c-axis lying in the film plane. The in-plane and the out-of-plane lattices are respectively more expanded and contracted in the continuous-lattice MgO/FePt/MgO structure due to accommodations of misfits of FePt film with respect to not only the MgO substrate but also the MgO cap-layer. The lattice deformation promotes phase transformation along the perpendicular direction and L10 ordering. The FePt films consisting of only L10(001) variant show strong perpendicular magnetic anisotropies and low in-plane coercivities. The present study shows that an introduction of epitaxial cap-layer is effective in controlling the c-axis perpendicular to the substrate surface.
Study of switching behavior of exchange-coupled nanomagnets by transverse magnetization metrology
Authors: Dey Himadri S. , Csaba Gyorgy , Bernstein Gary H. , Porod Wolfgang
Published: March 2017

We investigate the static switching modes of nanomagnets patterned from antiferromagnetically exchange-coupled magnetic multilayers, and compare them to nanomagnets having only dipole coupling between the ferromagnetic layers. Vibrating sample magnetometry experiments, supported by micromagnetic simulations, reveal two distinct switching mechanisms between the exchange-coupled and only dipole-coupled nanomagnets. The exchange-coupled nanomagnets exhibit gradual switching of the layers, dictated by the strong antiferromagnetic exchange coupling present between the layers. However, the layers of the only dipole-coupled nanomagnets show abrupt nucleation/growth type switching. A comprehensive understanding of the switching modes of such layered and patterned systems can add new insight into the reversal mechanisms of similar systems employed for spintronic and magneto-logic device applications.
One dimensional FexCo1-x nanowires; ferromagnetic resonance and magnetization dynamics
Authors: Aslam Shehreen , Khanna Manoj , Kuanr Bijoy K. , Celinski Z.
Published: March 2017

Soft magnetic nanowires (NWs) are widely used for microwave and mm-wave components. The investigation of magnetization damping behavior of NWs have attracted great interest due to large influence of loss to the device, like integrated microwave device, magnetic sensors, and magnetic random access memory. With increasing operational frequency and degree of integration, the requirements to characterize 1-dimensional NWs become increasingly high. The purpose of this work is to study the magnetization dynamics in FexCo1-x NWs. A series of FexCo1-x (x=0, 0.25, 0.5, 0.75, 1) NWs were grown by controlled electro-deposition. By adjusting FexCo1-x concentration (x=0 to 1), the saturation magnetization, increased more than 20%. Ferromagnetic resonance (FMR) both in field and frequency sweep mode are employed to characterize the NWs in flip-chip geometry. It is observed that FMR field (Hr) increases with increase in applied frequency. At a fixed frequency, Fe NWs resonate at a lower field than the Co substituted NWs. FMR field linewidth (ΔH) as well as frequency width (Δf) are largest for Co NWs and decreased for Fe NWs. Whereas ΔH and Δf decreased further for FexCo1-x nanowires with increasing x.
Accurate 3D multi-material EM-thermal modelling
Authors: Cen Wei , Hoppe Ralph , Cai Zhaoquan , Yu Zhuliang , Gu Ning
Published: March 2017

As the second order finite difference expressions discretize the spatial derivatives in heat equation accurately only for the homogenous material model with constant thermal conductivity, we proposed a method to numerically determinate 3-dimensional thermal response due to electromagnetic exposure accurately even for inhomogenous model. In this paper, the 3-dimensional (3D) EM-thermal modelling is performed with finite volume method. High numerical accuracy of the proposed method allow in vitro experiments with inhomogeneous tissues and non-uniform meshes. The validity of the method is demonstrated by comparing results with the fraction-step semi-implicit method.
Magneto-viscosity of hydrothermal synthesized Cu-Zn ferrite ferrofluids
Authors: Gautam Nisha , Thirupathi Gadipelly , Singh Rajender
Published: March 2017

The paraffin based ferrofluids were synthesized using the oleic acid coated Cu-Zn ferrite (CZF) nanoparticles of compositions Cu0.6Zn0.4Fe2O4 (CZF1) and Cu0.4Zn0.6Fe2O4 (CZF2) synthesized by hydrothermal process. The transmission electron micrographs (TEM) show the cubic shape particles of 4 to 10 nm and 4 to 18 nm size for CZF1 and CZF2 respectively. The nanoparticles show superparamagnetic behaviour. The viscosity increases with increase in magnetic field due to the formation of long chains of magnetic nanoparticles in ferrofluid. At higher flow rate, the magnetic chains break into smaller units and arrange along the flow direction. The flow curves show power law behavior. The size of magnetic nanoparticles influences the magneto-viscosity of the ferrofluids.
Development of the apparatus for measuring magnetic properties of electrical steel sheets in arbitrary directions under compressive stress normal to their surface
Authors: Maeda Yoshitaka , Urata Shinya , Nakai Hideo , Takeuchi Yuuya , Yun Kyyoul , Yanase Shunji , Okazaki Yasuo
Published: March 2017

In designing motors, one must grasp the magnetic properties of electrical steel sheets considering actual conditions in motors. Especially important is grasping the stress dependence of magnetic power loss. This paper describes a newly developed apparatus to measure two-dimensional (2-D) magnetic properties (properties under the arbitrary alternating and the rotating flux conditions) of electrical steel sheets under compressive stress normal to the sheet surface. The apparatus has a 2-D magnetic excitation circuit to generate magnetic fields in arbitrary directions in the evaluation area. It also has a pressing unit to apply compressive stress normal to the sheet surface. During measurement, it is important to apply uniform stress throughout the evaluation area. Therefore, we have developed a new flux density sensor using needle probe method. It is composed of thin copper foils sputtered on electrical steel sheets. By using this sensor, the stress can be applied to the surface of the specimen without influence of this sensor. This paper described the details of newly developed apparatus with this sensor, and measurement results of iron loss by using are shown.
Structure and magnetism of Fe-doped BaSnO3 thin films
Authors: Alaan Urusa S. , N’Diaye Alpha T. , Shafer Padraic , Arenholz Elke , Suzuki Yuri
Published: March 2017

BaSnO3 is an excellent candidate system for developing a new class of perovskite-based dilute magnetic semiconductors. In this study, we show that BaSn0.95Fe0.05O3 can be grown from a background pressure of ∼2×10−3 mTorr to oxygen pressures of 300 mTorr with high crystallinity and excellent structural quality. When grown in vacuum, the films may be weakly ferromagnetic with a nonzero x-ray magnetic circular dichroism signal on the Fe L3 edge. Growth with oxygen flow appears to suppress magnetic ordering. Even for very thick films grown in 100 mTorr O2, the films are paramagnetic. The existence of ferromagnetism in vacuum-grown BaSnO3 may be attributed to the F-center exchange mechanism, which relies on the presence of oxygen vacancies to facilitate the ferromagnetism. However, other possible extrinsic contributions to the magnetic ordering, such as clusters of Fe3O4 and FeO or contamination can also explain the observed behavior.
Tunneling magnetoresistance sensors with different coupled free layers
Authors: Liu Yen-Fu , Yin Xiaolu , Yang Yi , Ewing Dan , De Rego Paul J. , Liou Sy-Hwang
Published: March 2017

Large differences of magnetic coercivity (HC), exchange coupling field (HE), and tunneling magnetoresistance ratio (TMR) in magnetic tunnel junctions with different coupled free layers are discussed. We demonstrate that the magnetization behavior of the free layer is not only dominated by the interfacial barrier layer but also affected largely by the magnetic or non-magnetic coupled free layers. All these parameters are sensitively controlled by the magnetic nanostructure, which can be tuned also by the magnetic annealing process. The optimized sensors exhibit a large field sensitivity of up to 261%/mT in the region of the reversal synthetic ferrimagnet at the pinned layers.
Research Update: Density functional theory investigation of the interactions
of silver nanoclusters with guanine
Authors: Dale Brandon B. , Senanayake Ravithree D. , Aikens Christine M.
Published: March 2017

Bare and guanine-complexed silver clusters Agnz (n = 2-6; z = 0-2) are examined using density functional theory to elucidate the geometries and binding motifs that are present experimentally. Whereas the neutral systems remain planar in this size range, a 2D-3D transition occurs at Ag5+ for the cationic system and at Ag42+ for the dicationic system. Neutral silver clusters can bind with nitrogen 3 or with the pi system of the base. However, positively charged clusters interact with nitrogen 7 and the neighboring carbonyl group. Thus, the cationic silver-DNA clusters present experimentally may preferentially interact at these sites.
Gadolinium thin films as benchmark for magneto-caloric thin films
Authors: Helmich Lars , Bartke Marianne , Teichert Niclas , Schleicher Benjamin , Fähler Sebastian , Hütten Andreas
Published: March 2017

We report on the preparation of Gadolinium thin films by means of sputter deposition on Silicon Oxide wafers. A series of samples with different buffer layers and various substrate temperatures has been produced. The film on an amorphous Tantalum buffer deposited at 773 K shows the highest increase of magnetization during the phase transition at the Curie temperature. Further detailed analysis of the magnetic properties has been conducted by VSM.
Controlling the microstructure and associated magnetic properties of Ni0.2Mn3.2Ga0.6 melt-spun ribbons by annealing
Authors: Khan Mahmud , Alshammari Ohud , Balasubramanian Balamurugan , Das Bhaskar , Sellmyer David J. , Saleheen Ahmad Us , Stadler Shane
Published: March 2017

Here we report on the structural and magnetic properties of Ni0.2Mn3.2Ga0.6 melt-spun ribbons. The as-spun ribbons were found to exhibit mixed cubic phases that transform to non-cubic structure upon annealing. Additionally, an amorphous phase was found to co-exist in all ribbons. The SEM images show that minor grain formation occurs on the as-spun ribbons. However, the formation of extensive nano-grains was observed on the surfaces of the annealed ribbons. While the as-spun ribbons exhibit predominantly paramagnetic behavior, the ribbons annealed under various thermal conditions were found to be ferromagnetic with a Curie temperature of about 380 K. The ribbons annealed at 450 °C for 30 minutes exhibit a large coercive field of about 2500 Oe. The experimental results show that the microstructure and associated magnetic properties of the ribbons can be controlled by annealing techniques. The coercive fields and the shape of the magnetic hysteresis loops vary significantly with annealing conditions. Exchange bias effects have also been observed in the annealed ribbons.
Relationship between ion concentration of ferrofluid and response signals of magnetic nanoparticles against ac magnetic fields
Authors: Oda Shoya , Kitamoto Yoshitaka
Published: March 2017

Harmonic components of magnetic signals from ferrofluids excited by alternating magnetic fields are studied in view of applications to liquid sensing. The harmonic signals from ferrofluids of iron-oxide magnetic nanoparticles excited at the field strength of 100 mTp-p and the frequency range from 1510−6500 Hz are detected by a pickup coil and are processed with a lock-in amplifier. The harmonic signal exhibits a minimum in the frequency dependence at a frequency, which is correlated to the magnetic relaxation. The minimum frequency is decreased and the minimum value is increased with the increase of the ion concentration; the frequency dependence around the minimum frequency exhibits characteristic features depending on the ion concentration. The features are originated from polydispersity in the aggregation formed in the ferrofluids at higher ion concentration, and are different from the frequency characteristics depending on the viscosity. This magnetic relaxometry using the harmonic signals is useful for ion sensing in liquids without the influence of viscosity.
Antiferromagnetic spin current rectifier
Authors: Khymyn Roman , Tiberkevich Vasil , Slavin Andrei
Published: March 2017

It is shown theoretically, that an antiferromagnetic dielectric with bi-axial anisotropy, such as NiO, can be used for the rectification of linearly-polarized AC spin current. The AC spin current excites two evanescent modes in the antiferromagnet, which, in turn, create DC spin current flowing back through the antiferromagnetic surface. Spin diode based on this effect can be used in future spintronic devices as direct detector of spin current in the millimeter- and submillimeter-wave bands. The sensitivity of such a spin diode is comparable to the sensitivity of modern electric Schottky diodes and lies in the range 102-103 V/W for 30×30 nm2 structure.
Design and validation of magnetic particle spectrometer for characterization of magnetic nanoparticle relaxation dynamics
Authors: Garraud Nicolas , Dhavalikar Rohan , Maldonado-Camargo Lorena , Arnold David P. , Rinaldi Carlos
Published: March 2017

The design and validation of a magnetic particle spectrometer (MPS) system used to study the linear and nonlinear behavior of magnetic nanoparticle suspensions is presented. The MPS characterizes the suspension dynamic response, both due to relaxation and saturation effects, which depends on the magnetic particles and their environment. The system applies sinusoidal excitation magnetic fields varying in amplitude and frequency and can be configured for linear measurements (1 mT at up to 120 kHz) and nonlinear measurements (50 mT at up to 24 kHz). Time-resolved data acquisition at up to 4 MS/s combined with hardware and software-based signal processing allows for wide-band measurements up to 50 harmonics in nonlinear mode. By cross-calibrating the instrument with a known sample, the instantaneous sample magnetization can be quantitatively reconstructed. Validation of the two MPS modes are performed for iron oxide and cobalt ferrite suspensions, exhibiting Néel and Brownian relaxation, respectively.
Perpendicular magnetic anisotropy of CoFeB\Ta bilayers on ALD HfO2
Authors: Vermeulen Bart F. , Wu Jackson , Swerts Johan , Couet Sebastien , Radu Iuliana P. , Groeseneken Guido , Detavernier Christophe , Jochum Johanna K. , Van Bael Margriet , Temst Kristiaan , Shukla Amit , Miwa Shinji , Suzuki Yoshishige , Martens Koen
Published: March 2017

Perpendicular magnetic anisotropy (PMA) is an essential condition for CoFe thin films used in magnetic random access memories. Until recently, interfacial PMA was mainly known to occur in materials stacks with MgO\CoFe(B) interfaces or using an adjacent crystalline heavy metal film. Here, PMA is reported in a CoFeB\Ta bilayer deposited on amorphous high-κ dielectric (relative permittivity κ=20) HfO2, grown by atomic layer deposition (ALD). PMA with interfacial anisotropy energy Ki up to 0.49 mJ/m2 appears after annealing the stacks between 200°C and 350°C, as shown with vibrating sample magnetometry. Transmission electron microscopy shows that the decrease of PMA starting from 350°C coincides with the onset of interdiffusion in the materials. High-κ dielectrics are potential enablers for giant voltage control of magnetic anisotropy (VCMA). The absence of VCMA in these experiments is ascribed to a 0.6 nm thick magnetic dead layer between HfO2 and CoFeB. The results show PMA can be easily obtained on ALD high-κ dielectrics.
Enhanced coercivity in Co-doped α-Fe2O3 cubic nanocrystal assemblies prepared via a magnetic field-assisted hydrothermal synthesis
Authors: Gandha Kinjal , Mohapatra Jeotikanta , Poudyal Narayan , Elkins Kevin , Liu J. Ping
Published: March 2017

Ferromagnetic Co-doped α-Fe2O3 cubic shaped nanocrystal assemblies (NAs) with a high coercivity of 5.5 kOe have been synthesized via a magnetic field (2 kOe) assisted hydrothermal process. The X-ray diffraction pattern and Raman spectra of α-Fe2O3 and Co-doped α-Fe2O3 NAs confirms the formation of single-phase α-Fe2O3 with a rhombohedral crystal structure. Electron microscopy analysis depict that the Co-doped α-Fe2O3 NAs synthesized under the influence of the magnetic field are consist of aggregated nanocrystals (∼30 nm) and of average assembly size 2 μm. In contrast to the NAs synthesized with no magnetic field, the average NAs size and coercivity of the Co-doped α-Fe2O3 NAs prepared with magnetic field is increased by 1 μm and 1.4 kOe, respectively. The enhanced coercivity could be related to the well-known spin–orbit coupling strength of Co2+ cations and the redistribution of the cations. The size increment indicates that the small ferromagnetic nanocrystals assemble into cubic NAs with increased size in the magnetic field that also lead to the enhanced coercivity.
Design of high-throughput and low-power true random number generator utilizing perpendicularly magnetized voltage-controlled magnetic tunnel junction
Authors: Lee Hochul , Ebrahimi Farbod , Amiri Pedram Khalili , Wang Kang L.
Published: March 2017

A true random number generator based on perpendicularly magnetized voltage-controlled magnetic tunnel junction devices (MRNG) is presented. Unlike MTJs used in memory applications where a stable bit is needed to store information, in this work, the MTJ is intentionally designed with small perpendicular magnetic anisotropy (PMA). This allows one to take advantage of the thermally activated fluctuations of its free layer as a stochastic noise source. Furthermore, we take advantage of the voltage dependence of anisotropy to temporarily change the MTJ state into an unstable state when a voltage is applied. Since the MTJ has two energetically stable states, the final state is randomly chosen by thermal fluctuation. The voltage controlled magnetic anisotropy (VCMA) effect is used to generate the metastable state of the MTJ by lowering its energy barrier. The proposed MRNG achieves a high throughput (32 Gbps) by implementing a 64×64 MTJ array into CMOS circuits and executing operations in a parallel manner. Furthermore, the circuit consumes very low energy to generate a random bit (31.5 fJ/bit) due to the high energy efficiency of the voltage-controlled MTJ switching.
Micromagnetic simulation for the magnetization reversal process of Nd-Fe-B hot-deformed nanocrystalline permanent magnets
Authors: Tsukahara Hiroshi , Iwano Kaoru , Mitsumata Chiharu , Ishikawa Tadashi , Ono Kanta
Published: March 2017

We numerically demonstrated the magnetization reversal process inside a hot-deformed nanocrystalline permanent magnet. We performed large-scale micromagnetics simulation based on the Landau–Lifshitz–Gilbert equation with 0.1 billion calculation cells. The simulation model for the hot-deformed nanocrystalline permanent magnet consists of 2622 tabular grains that interact with each other by inter-grain exchange and dipole interactions. When the strength of the external field approached a coercive force, nucleation cores were created at the grain surface. The magnetization reversal was propagated by the inter-grain and dipole interactions. When the grains had overlapping regions parallel to the external field, the magnetization reversal propagated quickly between the grains due to the dipole interaction. In contrast, the motion of the magnetic domain wall was inhibited at interfaces between the grains perpendicular to the external field. Reversal magnetic domains had a pillar-shaped structure that is parallel to the external field. In the perpendicular direction, the reversal magnetic domain expanded gradually because of the inhibition of the domain wall motion.
High power, low divergent, substrate emitting quantum cascade ring laser in continuous wave operation
Authors: Wu D. H. , Razeghi M.
Published: March 2017

We demonstrate a surface grating coupled substrate emitting quantum cascade ring laser with high power room temperature continuous wave operation at 4.64 μm. A second order surface metal/semiconductor distributed-feedback grating is used for in-plane feedback and vertical out-coupling. A device with 400 μm radius ring cavity exhibits an output power of 202 mW in room temperature continuous wave operation. Single mode operation with a side mode suppression ratio of 25 dB is obtained along with a good linear tuning with temperature. The far field measurement exhibits a low divergent concentric ring beam pattern with a lobe separation of ∼0.34°, which indicates that the device operates in fundamental mode (n = 1).
Optimized neural network based thermal and electrical scheduling of virtual power plant in the presence of energy storage
Authors: Mohammadinia Samakoosh Hajar , Ghasemi Jamal , Kazemitabar Javad
Published: March 2017

Increasing energy consumption in the world and the presence of distributed generation pose new challenges in the management and operation of electrical grids. Virtual Power Plants (VPPs) and optimization methods assist in the integration of distributed energy resources in the power systems. One way of optimization is the use of Artificial Neural Networks (ANNs). This paper presents a new ANN based method for short-term scheduling of internal resources of a VPP in order to maximize its profit in a period of 24-h. This model is proposed to find an optimized method for connecting to the resources and VPP. The proposed model can be a way to fill the lack of a standard interface in technical problems with VPPs. Because of the different market and regulation conditions, applying an expert system, like a ANN that is independent of these rules, can be attractive. It should be mentioned that the proposed method has been examined on field data that were obtained from the power plant in Tuscany, operating in the range of 6 to 20 kW. As it is shown in the results, in the peak load condition, the Radial Basis Function (RBF) has an average error of 4% and performs better than the Multilayer Perceptron (MLP). However, in the intermittent load condition, the MLP has an average error of 6% and does better than the RBF. Nevertheless, both the MLP and the RBF have similar performance in the off-peak load condition.
Integrating Commercial Fisheries Registration, Education, and Social Science in the U.S. Virgin Islands
Authors: Crosson Scott , Hibbert Lia
Published: March 2017

The collection of economic data on commercial fisheries without a formal dealer network often requires time and labor-intensive field research. Previous fisheries social and economic research in the Caribbean has embraced stratified or cluster sampling techniques as an efficient alternative to seeking large random samples. We explore an alternative approach wherein fisheries education and research are incorporated into a registration process structured around small group interactions in the U.S. Virgin Islands (USVI). We find that this approach can raise response rates and save considerable effort, but the surveys themselves must be very brief.

Received February 11, 2016; accepted October 28, 2016 Published online March 1, 2017
Reconsidering the technologies of intellectual inquiry in curriculum design
Authors: Costa Cristina , Harris Lisa
Published: March 2017

This paper reports on the design and delivery of classroom pedagogies and students’ engagement with it in two different UK universities. Under the banner of curriculum design and Bourdieu's curriculum principles, the study set out to create modules that provided students with an interdisciplinary perspective on how the web is changing the way citizens live, interact and learn. Focusing on the idea that the web is becoming a tool of intellectual inquiry and an instrument of reproduction of knowledge inequality, the goal of this research was to transform knowledge practices by encouraging a learning habitus that relies on knowing how to learn rather than becoming ‘knowledgeable.’

The paper concludes that the Bourdieuian perspective on curriculum design still holds currency in the digital age, given that it shares an epistemology of practice similar to that advocated by a digital participatory culture. We also offer a critique to our approach, using Bourdieu's logic of practice to examine how education as a field displays (hidden) rules that students embody as their learning habitus. As students’ learning practices become doxified through their educational trajectories, learners find it difficult to engage with a curriculum that aims to diversify pedagogical structures and reflect a changing society.
From divergent evolution to witting cross‐fertilisation: the need for more awareness of potential inter‐discursive communication regarding students' extended historical writing
Authors: Carroll James Edward
Published: March 2017

History education stakeholders in England have consistently judged that some students find formal historical writing prohibitively difficult due to the demands of constructing an extended argument. While policy makers have agreed students need support in their historical writing, recurring themes in centralised resourcing have been wastage, incoordination and replication. Furthermore, two concurrent but largely disconnected discourses have developed and promulgated initiatives relevant to students’ extended historical writing: ‘genre theorists’ and the ‘history teachers’ extended writing movement’. Despite certain goals held in common participants in the two discourses have tended to talk past one another with concomitant issues in resourcing. Unsystematic, cross‐fertilisation between the discourses has led to cycles of genre theory being collectively discovered, forgotten, and rediscovered by history teachers with knowledge not being built cumulatively. Furthermore both discourses have independently developed similar initiatives in a form of convergent evolution resulting in duplication of labour. Finally, divergent evolution has occurred where genre theorists have advocated approaches that are increasingly redundant for history teachers’ requirements. A more activist stance is therefore required to ensure meaningful inter‐discursive communication between genre theorists and the history teachers’ ‘extended writing movement’ to ensure efficacy in developing approaches to improving students’ extended historical writing.
The Dark Side of Crime Prevention Through Environmental Design (CPTED)
Authors: Cozens Paul , Love Terence
Published: March 2017

This chapter provides an overview of the principles of Crime Prevention Through Environmental Design (CPTED). The paper focuses on the “dark side” of CPTED, a relatively underreported element to this theory, which relate to the negative outcomes that can result if CPTED is not implemented thoughtfully and equitably as a process. This chapter highlights why it is important to understand the “dark side” and provides examples of “dark-side” CPTED outcomes, such as the excessive use of target hardening, governance issues, and the use of CPTED as “crime prevention through exclusionary design.” The chapter highlights CPTED as a process, which can be enhanced to consider “dark-side” issues, using program logic models.
Community Participation in School Management in Developing Countries
Authors: Nishimura Mikiko
Published: March 2017

Community participation in school management has great potentials for removing mistrust and distance between people and schools by nurturing transparency of information and a culture of mutual respect and by jointly pursuing improvement of school by sharing vision, process, and results. Individual and organizational behavioral changes are critical to increase the level of participation. In countries where the administrative structures are weak, the bottom-up approach to expanding educational opportunity and quality learning may be the only option.

Nevertheless, when community participation is implemented with a top-down manner without wider consultation on its aims, processes, and expected results, the consequences are likely to be conflicts between actors, a strong sense of overwhelming obligation, fatigue, inertia, and disparity in the degree and results of community participation between communities. Political aspects of school management and socio-cultural difference among the population require caution, as they are likely to induce partial participation or nonparticipation of the community at large. Community participation in school management will result in a long-term impact only if it involves a wide range of actors who can discuss and practice the possibilities of revisiting the definition of community and the way it should be.
Urbanization in East Africa, circa 900–2010 CE
Authors: Burton Andrew
Published: March 2017

East Africa’s urban past is broken down into five historical periods. The first (c. 900–1500 ce) saw the emergence of an urban Swahili culture on the East African coast that flourished thanks to its role as economic and cultural arbiter between the African interior and the Indian Ocean world. Between 1500 and 1800, as in other parts of the world, the intrusion of Europeans (and other outsiders) appears to have had a detrimental impact on “classical” Swahili civilization, although several important urban centers continued to flourish. Inland there is negligible evidence of urbanization before 1800. From around this time, however, important settlements did arise in the interior, thanks largely to the region’s growing integration in an international economy that emerged in the course of the 19th century—with various coastal (Swahili) cities prospering once again through their intermediary role. The situation was transformed with the onset of European colonial rule (c. 1890–1960), which prompted historically unprecedented rates of urban growth and witnessed the emergence of what would become a number of important world cities. Toward the end of the colonial period, from the 1940s, East Africa’s urban centers experienced another upward jolt in their rates of growth; however, the full repercussions of this demographic revolution, which resulted in a substantial (and growing) proportion of the population claiming urban residence for the first time, did not become fully apparent until after independence; with rapid urbanization proving one of the most important features of postcolonial East Africa.
Humor in Language
Authors: Attardo Salvatore
Published: March 2017

Interest in the linguistics of humor is widespread and dates since classical times. Several theoretical models have been proposed to describe and explain the function of humor in language. The most widely adopted one, the semantic-script theory of humor, was presented by Victor Raskin, in 1985. Its expansion, to incorporate a broader gamut of information, is known as the General Theory of Verbal Humor. Other approaches are emerging, especially in cognitive and corpus linguistics. Within applied linguistics, the predominant approach is analysis of conversation and discourse, with a focus on the disparate functions of humor in conversation. Speakers may use humor pro-socially, to build in-group solidarity, or anti-socially, to exclude and denigrate the targets of the humor. Most of the research has focused on how humor is co-constructed and used among friends, and how speakers support it. Increasingly, corpus-supported research is beginning to reshape the field, introducing quantitative concerns, as well as multimodal data and analyses. Overall, the linguistics of humor is a dynamic and rapidly changing field.