bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper Phthalocyanine Functionalized Single-Walled Carbon Nanotubes: Thin Film Deposition and Sensing Properties
Authors: Banimuslem Hikmat , Hassan Aseel , Basova Tamara , Yushina Irina , Durmuş Mahmut , Tuncel Sinem , Esenpınar Aliye Aslı , Gürek Ayse Gül , Ahsen Vefa
Published: April 2014

Thin films of non-covalently hybridised single-walled carbon nanotubes (SWCNT) and tetra-substituted copper phthalocyanine (CuPcR4) molecules have been produced. The π-π interaction between SWCNTs and CuPcR4 molecules has been revealed by using different characterisation techniques. Scanning electron microscopy (SEM) measurements have shown that films obtained from the acid-treated SWCNTs/CuPcR4 hybrids demonstrated more homogenous surface. Using total internal reflection ellipsometry spectroscopy (TIRE), thin films of the new hybrid have been examined as an optical sensing membrane for the detection of benzo [pyrene in water to demonstrate the sensing properties of the hybrid.
Fabrication of Tips for Magnetic Force Microscopy Employing Magnetic Multilayer Structures
Authors: Suzuki Ryo , Ishihara Shinji , Ohtake Mitsuru , Futamoto Masaaki
Published: April 2014

Magnetic force microscope (MFM) tips are prepared by coating Si tips of 4 nm radius with [Co (1 nm)/M(1 nm)]20 (M = Pt, Pd, Ni) multilayer films. An MFM tip prepared by coating 40-nm-thick Co film is employed as a reference tip. The influences of M layer material on the spatial resolution and the switching field of MFM tip are investigated. The spatial resolutions of Co/M multilayer coated tips are estimated to be within 9.4 ± 0.3 nm for all the M materials, which is about 6% inferior to that of Co coated tip (8.8 nm). Higher switching fields of 1425 and 825 Oe are respectively observed for the tips coated with Co/Pt and Co/Pd multilayers, whereas the field of tip coated with Co/Ni multilayer is 275 Oe which is similar to that of Co coated tip (325 Oe). The switching field is influenced by the magnetic anisotropy of multilayer film. An MFM tip coated with Co/Pt multilayer film is useful to observe the magnetic domain structure of permanent magnets and magnetic recording media.
Preparation of 3d Ferromagnetic Transition Metal Thin Films with Metastable bcc Structure on GaAs(100) Substrates
Authors: Ohtake Mitsuru , Minakawa Shigeyuki , Futamoto Masaaki
Published: April 2014

Ni, permalloy (Py: Ni - 20 at. % Fe), and Co films of 40 nm thickness are prepared on GaAs (100) single-crystal substrates at room temperature and 200 °C by magnetron sputtering. The growth behavior and crystallographic properties are studied. In early stages of film growth, metastable bcc single-crystals nucleate on the substrates for all the film materials. The crystal structure is stabilized through hetero-epitaxial growth. With increasing the thickness beyond 2 nm, the bcc structure starts to transform into fcc or hcp structure through atomic displacements parallel to the bcc {110} close-packed planes. The transformation orientation relationships are fcc {111}<10>, hcp {0001}<110> || bcc {110}<001>. The resulting Ni and Py films consist of a mixture of bcc and fcc phases, whereas the Co films involve an hcp phase in addition to the metastable bcc phase.
Synthesis of Perovskite Sr Doped Lanthanide Cobaltites and Ferrites and Application for Oxygen Sensors: A Comparative Study
Authors: Cvejin Katarina , Manjakkal Libu , Kulawik Jan , Zaraska Krzysztof , Szwagierczak Dorota
Published: April 2014

Perovskites with formula A1-xSrxBO3-δ (A = La, Nd, Sm; B = Fe or Co) have been synthesized by solid state reaction method and have been studied as materials for oxygen sensor application. The obtained powders were used for making thick film pastes that were later screen printed as sensing electrodes on yttria stabilized zirconia (YSZ) substrates. Sensing electrodes were exposed to low concentration oxygen gas at elevated temperatures. Measurements of the electromotive force of electrochemical cells with the fabricated electrodes were carried out as a function of temperature. The investigation indicated that all of the synthesized materials show Nernstian behavior in a relatively wide temperature range, although the most promising for oxygen electrochemical sensor application is strontium doped samarium cobaltite.
Structure and Epitaxial Behavior of Rutile TiO2 Thin Films Prepared by DC Magnetron Sputtering and Ex-Situ Annealing
Authors: Roch Tomas , Durina Pavol , Truchly Martin , Plecenik Tomas , Grancic Branislav , Mikula Marian , Haidry Ali Azhar , Gregor Maros , Satrapinskyy Leonid , Kus Peter , Plecenik Andrej
Published: April 2014

Titanium dioxide gas sensors are typically employing metastable anatase nanocrystalline phase. Operation at high temperature can thus negatively affect their long term stability. Employment of rutile phase with strong texture and larger grain size may ensure better reliability and longer lifetime. Therefore in this work we study the possibility to utilize stable rutile phase thin films prepared at relatively low temperature on c-cut sapphire substrates. Technological conditions have been chosen in order to obtain highly oriented titanium dioxide rutile thin films using reactive DC magnetron sputtering on unheated substrates. Subsequent ex-situ annealing in temperature range from 500°C to 800°C leads to increase of crystallite size and improvement of in-plane preferential orientation. Surface topography has been characterized by atomic force microscopy. Structure, texture and the strain evolution has been investigated using x-ray diffraction measurements. All investigated thin films showed epitaxial relationship with respect to the substrate: rutile-TiO2(100)[00 || Al2O3(0001)[10. Sensitivity of such rutile films to hydrogen has been measured and compared with our previous results on anatase thin films.
Initial Calibration and Online Error Compensation of a Resolver System
Authors: Aung N.L.H. , Bi C. , Al-Mamun Abdullah
Published: April 2014

This paper presents a method for initial calibration and online compensation of systematic errors in a resolver system. Initial calibration at standstill condition is carried out for a few positions by applying Discrete Fourier Transform and Least Squares method. The error model is constructed based on complex Fourier expression of position angle signal obtained from non-ideal resolver signals due to amplitude imbalance, quadrature error and offset. Error parameters are determined online using the integral control loops which are initialized with the calibration results. Besides, single channel amplitude tracking is incorporated in the error compensation scheme. This makes the compensation adaptive to changes in error parameters. And thus accuracy of the resolver system is reasonably improved and the system becomes robust. The effectiveness of the proposed method is validated by simulation and experiments.
Preparation of Propiolic Acid Doped Polyaniline and Investigation of Opto-Electronic Properties
Authors: Ahlatcioglu Esma , Okutan Mustafa , Senkal Bahire Filiz
Published: April 2014

Among the conducting polymers, polyaniline is of vital importance as an electronicmaterial [1{4] because of its easy synthesis, environmental stability, reversible proton dopabil-ity, redox recyclability, cost-e ectiveness, and reasonable electrical conductivity. Electrical andoptoelectronic applications of conducting polymers often require high current densities thatcan be achieved by either heavy doping or a high-level carrier injection. Polyaniline occurs infour oxidation states (i.e., leucoemeraldine, emeraldine base, emeraldine salt, and pernigrani-line), out of which only emeraldine salt is conductive in nature (the others are insulating innature). Polyaniline (PANI) exists in a variety of forms that di er in chemical and physicalproperties [5{9].Polyaniline is one of the most promising conducting materials for applications in optoelec-tronics and microelectronics devices.The doping of polyaniline can be accomplished through protonic acid and oxidative doping.Protonic acid doping of emeraldine base units results in complete protonation of imine nitrogenatoms to give the fully protonated emeraldine salt [10, 11].The AC (alternative current) conductivity properties of Polyaniline (PANI) and doped PANIparallel plate materials were investigated by impedance spectroscopy. The real part of conduc-tivity (0), and the real part of impedance (Z0p) were measured in the logarithmic frequencyrange of 100 to 1.5x107 Hz at 25, 40, 50 and 100 C temperatures. The AC conductivity value ofthe undoped PANI is high values for polymeric materals to ionic conduction and electrode po-larization in low frequency. The alternative current (AC) conductivity increases with increasingMB concentration and the frequency.
Microwave Emission of Carbon Fibres during Electrical Breakdown
Authors: Aman Alexander , Majcherek Sören , Hirsch Sören
Published: April 2014

A new method of reliability monitoring of electrical devices based on carbon fibres is presented. Due to the thermo-mechanical stress on electronic circuits a loss of fibre network integrity can take place and potential difference may appear between the edges of broken carbon fibres. This potential difference causes an intensive field-emission from surfaces of these broken carbon fibres and an acceleration of emitted electrons. Due to the acceleration of electrons a microwave emission is generated. A CFRP was used to simulate the behaviour of a carbon based electronic device. The sequence of microwave impulses was detected in a frequency bandwidth from 8 to 12 GHz. The rise time of detected microwave impulses is about of few nanoseconds. This time is in agreement with crack formation time in carbon fibre. The correlation between the change of electrical resistance of composites and microwave impulses by fibres fracture is observed. Thus, the breakdown of current that flows through carbon fibres induces detectable microwave emission. That means that defects in electrical circuits can be wireless detected online.
Specific Futures of Optical Anisotropy in Terbium Iron and Terbium Gallium Garnets
Authors: Tsidaeva Natalia , Abaeva Viktorija , Turiev Anatoly , Enaldieva Elena , Butkhuzi Tengiz , Khaimanov Spartak , Ramonova Alena
Published: April 2014

We reported magnetooptical properties of Tb3+ in single crystals of Tb3Fe5O12 and Tb3Ga5O12 for ion occupying sites of D2 symmetry in the garnets structure. It is shown that in the employed Voigt geometry the magnetic linear birefringence and the dichroism reach values 10-4, and have a strong dependence on the wavelength and a strong anisotropy. The absorption spectra were obtained at temperatures of 30K, 100K using magnetic field up to 25 kOe applied parallel and perpendiculare to the electric vector E linearly polarized light on the 7F67F0 and 7F67F1 optical transitions region. The aim of this research was revealing of a role of contributions of exchange interaction and a crystal field in splitting of energy levels of the basic condition 7F6 ion Tb3+ multiplet in Tb ferrite-garnet by studying of character of spectra magnetic linear dichroism (MLD) paramagnetic and ferrimagnetic crystals placed in an external magnetic field. More over, the assumption about nonreciprocity of magnetic linear birefringence (MLB) spectra and dichroism with the change of the relative orientation of the magnetization vector I and the light wave vector has been experimentally confirmed. This effect may use as a base for the design of the different transducers, for example, magnetooptical optical channels commutator.
Ab Initio Study of Electronic Structure under Hydrostatic Pressure in Ferromagnetic MnxGe1-x Alloy
Authors: Djeroud Sacia , Bouchahdane Ibtissem
Published: April 2014

In the fields of spintronics, extensive experiments and theoretical studies have been performed to discover materials that are ferromagnetic at room temperature. Many materials have attracted a great interest due to their potential applications in this area and their new physical properties. Our aim in this work is to study the electronic structure of Mn-doped Ge under pressure effect. We used the full-potential linearized augmented plane wave plus the local orbitals method based on the density functional theory within the generalized gradient approximation as parameterized by Perdew. Our calculations were ported on a 2x2x2 Germanium supercell where Ge atom in position (0, 0, 0) was substituted by Mn atom. The theoretical equilibrium lattice parameters are determined. The electronic band structures calculated at equilibrium show the half metallic character of MnxGe1-x. The totat density of states demonstrate the half metallicity under pressure of MnxGe1-x. In addition, the magnetic moment of the super-cell increases under pressure while the magnetic moment of Mn decreases with pressure increasing which is consistent with the available data.Keywords: spintronic, ferromagnetic, hydrostatic pressure, electronic properties, DFT.
Different Chemical Approaches for the Synthesis of Polyaniline Nanofibers and its Application in Ammonia Gas Sensing
Authors: Talwar Vivek , Singh Ravi Chand
Published: April 2014

Polyaniline nanofibers of varying morphology were synthesized using two different chemical methods. The polyaniline samples were prepared through the oxidation of aniline in an ice bath. In the first method, the oxidant is added drop wise in aniline solution whereas in other the samples were prepared via rapid mixing of oxidant into aniline solution. The structural and morphological analysis of prepared samples was carried out using XRD, FTIR and FESEM techniques. The thick films of the synthesized powder were deposited on alumina substrate and their sensing response to various volatile gases was investigated at room temperature. The morphology of synthesized polyaniline powder depends upon method of synthesis and thus effect the sensing response and selectivity of the fabricated sensor.
Hydrogen-Terminated Diamond Sensors for Electrical Monitoring of Cells
Authors: Izak Tibor , Novotná Katarína , Kopová Ivana , Bačáková Lucie , Varga Marián , Rezek Bohuslav , Kromka Alexander
Published: April 2014

In this paper we introduce fully optically transparent impedance biosensors based on intrinsic nanocrystalline diamond (NCD) films deposited on glass substrate. Prepared sensors have an interdigital electrode (IDE) structures realized by local hydrogen and oxygen termination of diamond surface, which mean in-plane configuration of active sensor area. Sensors were tested by real time monitoring of human osteoblast-like MG 63 cells in wide frequency range from 10 Hz to 100 kHz for several days. Two different measurement setups were used and compared regarding to their advantages and disadvantages. Proof of concept of diamond-based impedance sensor is showed, i.e. time dependence and frequency dependence (Nyquist plots) of absolute impedance.
Synthesis of ZnO Nanorod Arrays by Chemical Solution and Microwave Method for Sensor Application
Authors: Yahaya Muhammad , Tan Sin Tee , Umar Akrajas Ali , Yap C.C. , Salleh M.M.
Published: April 2014

One-dimensional ZnO semiconductor nanomaterials have been attracting increasing attention due to their outstanding properties, which are different from bulk materials. ZnO has a direct band gap of 3.37 eV and large exciton binding energy hence its nanowires and nanorods have been regarded as one of the most promising materials for nanoscale electronic and optoelectronic devices such as ultraviolet laser diodes, optical detectors and gas sensor. ZnO nanowires and nanorods have been successfully synthesized by various techniques such as evaporation, sputtering and pyrolysis. In this paper we report the preparation of nanorod arrays of ZnO on ITO glass substrates which were pre-coated with ZnO nanoparticles by using low temperature chemical solution method and the result was compared with microwave hydrolysis process. The morphology and structure of ZnO nanorod arrays were investigated using field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The ZnO nanorod arrays with a diameter of 40-70 nm were successfully synthesized. In microwave hydrolysis method, the diameter, density and surface roughness was found to depend on the microwave power. The microwave method is far superior in producing ZnO nanostructure growth.
The Effect of Frequency on the Flow and Particle Collection Patterns under Electroosmosis
Authors: Wei Che Hung , Wu Lin Chi
Published: April 2014

The collection and manipulation of small objects is important in bioassays. One commonly used force to manipulate small objects is electroosmosis which has the advantages of easy fabrication and small power consumption. Many factors affect the electroosmosis like surface charge density, applied voltage and frequency. For ac electroosmosis, frequency affects flow pattern and particle collection. In this study, the role of frequency is investigated by experiments and verified by numerical simulation. The electroosmosis collecting chip is made of two parallel electrodes separated by a spacer. The chip consists of a top ITO electrode and a bottom electrode made by Corning 1737 glass with different patterned sputtered Cr electrode. The spinning photoresist on the bottom electrode is used as dielectric layer and the electrodes are separated by a curing PDMS spacer. The amine-modified polystyrene particles were collected by varying frequency. To further investigate the mechanism, numerical simulations were carried out using commercial software Comsol with multi-physics setting. The results show the particle flow and collection pattern is sensitive to frequency. For low frequency 100 Hz, the maximum flow velocity occurred in the peripheral boundary of the bottom electrode and the particles are depleted in the central and accumulated in the peripheral area. For high frequency 1000 Hz, the particles are accumulated in the center region of the bottom electrode where the maximum velocity occurs. From simulation, the maximum flow velocity occurs from the boundary towards the center as frequency increases. Meanwhile, the magnitude of the maximum flow velocity is also proportional to the applied frequency. For particles collected by electroosmosis, varying frequency will result in different flow and collection pattern.
A Mass Efficiency Test of α-β Processed Ti-Al-V Alloys
Authors: Antipas G.S.E.
Published: April 2014

Titanium alloys, synthesised from scrap metals and α-β rolled above the transus temperature, yielded enhanced mass-efficiency when formed into plates comprising 3.0-5.0% Al, 2.0-3.0% V and up to 0.3% O, exceeding roughly 5% the penetration velocities set by the ballistic standard.
An Investigation of Elastic Stress (Strain) - Induced Subtle Magnetic Changes in Steels
Authors: Kytopoulos V.N. , Ioakeimidis E.K.
Published: April 2014

By means of a simple energy discrimination technique it was possible to show the stress induced formation of two distinct ranges of Barkhausen micromagnetic activity. The formation of these ranges was attributed to the existence of two different modes of domain wall motion each of which was related to the grain boundaries as well as the grain interior activity. By adopting an exponential energetic count distribution approach a semi-quantitative estimation of the tensile stress-induced magnetic changes was given. In this context it was shown that the experimentally obtained low limit elastic stress, at which magnetic changes set on, are in reasonably agreement with existing theoretical values. It was also show that the externally supplied elastic stress (strain) energy leads to a shift of the energy distribution spectrum of the emitted Barkhausen counts to higher energies.
Correlation of Magnetic Properties and Ductile-to-Brittle Transition Temperature in Pipelines
Authors: Kotoula Garifalia
Published: April 2014

Drop-weight tear tests were conducted on high toughness pipeline steel, in order to analyze by fractography study the fracture appearance, occurring in the region impacted by a hammer. Measurements of hysteresis loops, in a range of very low temperatures (-20°C to-60°C), have been performed on samples in order to correlate its magnetic properties with the percentage reduction of the ductile area and the range of ductile to brittle transition temperature. According to the results, magnetic permeability depends on critical transition temperature.
A Critical Assessment of the Four Basic Methods of Tomographic Imaging
Authors: Mangiorou Eleni
Published: April 2014

Τhe incidence of and mortality from cancer have been increasing steadily for the past 50 years. Most cancers are not localized when first detected, but early detection is mandatory to improve prognosis. In this article, we performed a comparison of four basic methods of tomographic imaging, Positron emission tomography (PET), the computerized tomography (CT), Magnetic Resonance Imaging (MRI) scanner and the ultrasound scanner (US), in respect to their advantages and disadvantages.
Controlled Synthesis of Composite Iron Oxide Nanoparticles
Authors: Tserotas P. , Lazaridis T. , Statharas E.
Published: April 2014

In the course of this work, two iron oxide nanopowder samples (a mixture of FeO / γ-Fe2Ο3-Fe3O4) were composed, implementing the methodology. The synthesis used is a simple thermal decomposition route of organometallic precursors. The organometallic precursor used was the iron acetylacetonate (Fe (acac)3) which underwent reductive thermal degradation. The shape of the nanoparticles was examined and determined by the reaction time and the ratio of the used surfactants, oleic acid (OA) and oleylamine (OAm). The first sample underwent controlled oxidation in the air to transform the non-magnetic FeO phase to a mixture of magnetic phases, while the second sample underwent thermal reduction in a hydrogen atmosphere to produce a composite nanomaterial, with α-Fe, Fe3O4, γ-Fe2Ο3, being the dominant phases.
Development of Fluxgate Magnetometers Based on Fe61Co19Si5B15 Amorphous Ribbons
Authors: Vaitsi Sotiria
Published: April 2014

This paper deals with the characterization of fluxgate magnetometers that adopt a Fe61Co19Si5B15 ribbons as magnetic core. The experimental characterization concerned the dependence of Δt and ΔV according to the magnetic field Hdc. The change of the field (variable input) held by changing the offset, adding a small dc voltage to ac, taking in extremely important results. Still, examined the dependence of ΔV on the frequency for two different types of coils, a circular and an oval coil, made of the same material, Fe61Co19Si5B15.
BQJ Photodetector Signal Processing
Authors: Courcier Thierry , Pittet Patrick , Charette Paul G. , Aimez Vincent , Lu Guo Neng
Published: April 2014

We propose a signal processing method for the CMOS Buried Quad Junction (BQJ) photodetector employed for multi-label fluorescence detection. It serves to quantify label components in an arbitrary mixture with improved signal-to-noise ratio. The proposed method includes least squares optimization and statistical data preprocessing based on Principal Component Analysis (PCA). The method was applied to the BQJ as well as to Buried Double Junction (BDJ) and Buried Triple Junction (BTJ) detectors. The obtained results show that BQJ case achieves best accuracy in label quantification compared to BDJ and BTJ detectors in any tested configurations. The statistical data preprocessing approach was also evaluated: 5dB SNR improvements for an example case of two-label mixture (Green-Red excitation with optical power over 28pW).
NLRP3 Regulates Neutrophil Functions and Contributes to Hepatic Ischemia–Reperfusion Injury Independently of Inflammasomes
Authors: Inoue Yoshiyuki , Shirasuna Koumei , Kimura Hiroaki , Usui Fumitake , Kawashima Akira , Karasawa Tadayoshi , Tago Kenji , Dezaki Katsuya , Nishimura Satoshi , Sagara Junji , Noda Tetsuo , Iwakura Yoichiro , Tsutsui Hiroko , Taniguchi Shun’ichiro , Yanagisawa Ken , Yada Toshihiko , Yasuda Yoshikazu , Takahashi Masafumi
Published: April 2014

Inflammation plays a key role in the pathophysiology of hepatic ischemia–reperfusion (I/R) injury. However, the mechanism by which hepatic I/R induces inflammatory responses remains unclear. Recent evidence indicates that a sterile inflammatory response triggered by I/R is mediated through a multiple-protein complex called the inflammasome. Therefore, we investigated the role of the inflammasome in hepatic I/R injury and found that hepatic I/R stimuli upregulated the inflammasome-component molecule, nucleotide-binding oligomerization domain–like receptor (NLR) family pyrin domain–containing 3 (NLRP3), but not apoptosis-associated speck–like protein containing a caspase recruitment domain (ASC). NLRP3−/− mice, but not ASC−/− and caspase-1−/− mice, had significantly less liver injury after hepatic I/R. NLRP3−/− mice showed reduced inflammatory responses, reactive oxygen species production, and apoptosis in I/R liver. Notably, infiltration of neutrophils, but not macrophages, was markedly inhibited in the I/R liver of NLRP3−/− mice. Bone marrow transplantation experiments showed that NLRP3 not only in bone marrow–derived cells, but also in non-bone marrow–derived cells contributed to liver injury after I/R. In vitro experiments revealed that keratinocyte-derived chemokine–induced activation of heterotrimeric G proteins was markedly diminished. Furthermore, NLRP3−/− neutrophils decreased keratinocyte-derived chemokine–induced concentrations of intracellular calcium elevation, Rac activation, and actin assembly formation, thereby resulting in impaired migration activity. Taken together, NLRP3 regulates chemokine-mediated functions and recruitment of neutrophils, and thereby contributes to hepatic I/R injury independently of inflammasomes. These findings identify a novel role of NLRP3 in the pathophysiology of hepatic I/R injury.
Formation and failure of natural dams in the Canadian Cordillera
Authors: Clague J J , Evans S G
Published: April 2014

In western Canada, existing and former lakes dammed by landslides, moraines, and glaciers have drained suddenly to produce floods orders of magnitude larger than normal streamflows. Landslide dams consisting of failed bedrock generally are stable, whereas those
comprising Quaternary sediments or volcanic debris fail soon after they form, typically by overtopping and incision. Moraine dams are susceptible to failure because they are steep-sided and consist of loose, poorly sorted sediment. Irreversible rapid incision of a moraine dam may result from a large
overflow associated with a severe rainstorm, avalanche, or rockfall. Some glacier-dammed lakes drain suddenly through englacial and subglacial tunnels to produce large floods. Most outburst floods are characterized by an exponential increase in discharge, followed by an abrupt drop to background
levels when the water supply is exhausted. Peak discharges are controlled by lake volume, dam characteristics, failure mechanisms, and downstream topography and sediment availability. An appraisal of the likelihood that a natural dam will fail can be made by studying the dam, the reservoir, and the
surrounding terrain. A moraine dam may be hazardous if it contains ice or has a low width-to-height ratio, or if the reservoir is bordered by steep, rockfall- or avalanche-prone slopes. All glacier-dammed lakes with a recent history of outburst floods should be considered hazardous, but even
stable lakes may drain suddenly after a long period of glacier retreat. Many landslides dams fail soon after they form, consequently hazard appraisal may be concerned more with the location and size of potential dams than with the stability of existing dams.
U-Pb zircon evidence for circa 3.1 Ga crust south of the McDonald Fault, northwestern Canadian Shield, Northwest Territories
Authors: Henderson J B , Thériault R J
Published: April 2014

In the Artillery Lake area a 3129 +13/-10 Ma U-Pb (zircon) age from a tonalite gneiss south of the dextral McDonald Fault indicates that rocks of this terrane are distinct from lithologically similar gneisses of the 2.0-1.9 Ga Thelon Tectonic Zone north of the
fault. They are considered to be part of a zone of gneisses derived from Paleoarchean to Mesoarchean crust that occurs along the western Churchill Province margin east of the Taltson Magmatic Zone and Thelon Tectonic Zone.
Trace metals in the environment: a geological perspective
Authors: Rasmussen P E
Published: April 2014

This report examines current methods of estimating the relative contribution of anthropogenic and natural sources of metals in the environment, with particular attention to areas distant from industrial point sources. Natural background concentrations and cycling
processes must be known in order to assess the extent and impact of anthropogenic releases of metals to the environment. There are, however, critical information gaps and uncertainties associated with attempts to quantify the relative contribution of natural and anthropogenic sources to global,
regional, and local scale geochemical cycles. One important issue is the orders-of-magnitude uncertainty associated with global emissions inventories. Another important issue is the uncertainty associated with distinguishing natural accumulation processes from anthropogenic effects in the
interpretation of metal distribution in soil, vegetation, and lake sediments. Research is required to obtain robust estimates of annual metal contributions to water bodies and to the atmosphere from natural sources.
Ordovician and Silurian
Authors: Norford B S
Published: April 2014

During the early Paleozoic, the paleogeography of northern Yukon and adjacent District of Mackenzie was characterized by an intricate and changing pattern of platforms and adjacent troughs. Relatively deep water persisted in the Richardson and Blackstone troughs
throughout most of the Late Cambrian to Early Devonian. Carbonate rocks accumulated on shallow shelves and banks that bordered the two troughs, and carbonate sediments were shed into the basinal depositional environments of the troughs.
Unconformities are widespread within the carbonate successions of the Mackenzie Arch and the Porcupine Platform and can be detected locally on the Ogilvie Arch. In contrast, there is little evidence of breaks in the carbonate banks of the White Uplift and the Illtyd Range, located at the north and
south ends of the Richardson Trough respectively. The Richardson Trough subsided throughout the interval and the resulting Road River strata have a virtually complete biostratigraphic record spanning some 120 million years.
Thermal maturation studies indicate that most of the Ordovician and Silurian rocks have been heated too severely for the retention of oil and gas generated within the sediments. Little is known of the potential for base metal deposits, but the setting is analogous to those of the Selwyn Basin and
the Kechika Trough, where significant discoveries have been made of strata-bound deposits in basinal facies. Volcanics are prominent in the Road River Group in those areas, but some possible ash components of micrites are the only records of volcanic activity in the Road River Group in the
Richardson and Blackstone troughs.
Cretaceous and Tertiary
Authors: Dixon J
Published: April 2014

Cretaceous and Tertiary strata, which are widely exposed throughout the Operation Porcupine map area, consist of alternating shale- and sandstone-dominant formations. Sandstone-rich Lower Cretaceous strata tend to form a northeast-trending belt, extending from
the Tuktoyaktuk Peninsula, through the northern Richardson Mountains, and across the northern edge of Eagle Plain, turning southward along the northern Ogilvie Mountains. Northwestward of the sandstone belt, the succession tends to become shalier. The bulk of these Lower Cretaceous rocks are
easterly- to southeasterly-derived, shoreline to shelf sediments, dominated by storm deposits. However, in parts of northern Yukon, some Albian strata contain thick successions of westerly-derived sediment gravity-flow deposits formed during a major tectonic event associated with orogeny in the
ancestral Brooks Range. Berriasian to Aptian sedimentation was associated with rift tectonics, and during the late Aptian and Albian, the northern Yukon and adjacent Northwest Territories were subjected to both rifting and compression.
A major unconformity separates Lower and Upper Cretaceous strata. Upper Cretaceous and Tertiary strata reflect a different tectono-stratigraphic regime, wherein sediments were derived from the the rising Cordilleran orogen to the south and southwest. Cenomanian to early Maastrichtian sediments were
deposited in a cratonic foreland basin, whereas since Late Maastrichtian time, deposition has been on the subsiding continental margin of Canada Basin. Upper Cretaceous and Tertiary strata are dominated by deltaic and delta-front sediments in their onshore and nearshore occurrences, grading into
prodelta/shelf, slope and basinal deposits in the offshore areas.
Sources and types of information on self-care symptom management strategies for HIV and AIDS
Authors: Marie Modeste Regis R. , Majeke Sisana J.
Published: April 2014

Background: It has been reported that South Africa has the highest number of people living with HIV worldwide, with more women being infected than men. Women living with HIV have been documented as experiencing various symptoms related to HIV and use various strategies to manage these symptoms.Objective: The objective of this study was to explore the sources and types of information regarding self-care symptom management strategies received by women living with HIV.Method: The study was conducted at an HIV clinic in an urban area of KwaZulu-Natal. Individual in-depth interviews were completed with 11 women who were living with HIV,exploring the sources of information received on how they manage the HIV- (and/or AIDS-) related symptoms they experienced as well as the types of information received. The collecteddata were analysed using qualitative content analysis.Results: The participants identified various sources, which mainly included groups of people who provided them with information on how to manage their HIV-related symptoms, namely healthcare providers, their personal networks and the community. The different sources offered different types of information, including the use of medication, complementary treatments and self-comforting activities.Conclusion: The study highlights that participants used multiple sources to get information about how to manage the experienced symptoms related to HIV, namely, healthcare providers, family and friends as well as themselves. It is to be noted that each source provided a preferred type of information.
Mahler Measures as Linear Combinations ofL–values of Multiple Modular Forms
Authors: Samart Detchat
Published: April 2014

We study the Mahler measures of certain families of Laurent polynomials in two and three variables. Each of the known Mahler measure formulas for these families involvesL–values of at most one newform and/or at most one quadratic character. In this paper we show, either rigorously or numerically, that the Mahler measures of some polynomials are related toL–values of multiple newforms and quadratic characters simultaneously. The results suggest that the number of modularL–values appearing in the formulas significantly depends on the shape of the algebraic value of the parameter chosen for each polynomial. As a consequence, we also obtain new formulas relating special values of hypergeometric series evaluated at algebraic numbers to special values ofL–functions.
Influence of the Changjiang River on the light absorption properties of phytoplankton from the East China Sea
Authors: Wang S. Q. , Ishizaka J. , Yamaguchi H. , Tripathy S. C. , Hayashi M. , Xu Y. J. , Mino Y. , Matsuno T. , Watanabe Y. , Yoo S. J.
Published: April 2014

Abstract. Phytoplankton light absorption properties were investigated at the surface and subsurface chlorophyll a maximum (SCM) layer in the East China Sea (ECS), a marginal sea which is strongly influenced by the Changjiang discharge in summer. Results from ECS were compared with those from the Tsushima Strait (TS) where the influence of Changjiang discharge is less. The probable controlling factors, packaging effect (cell size) and pigment composition of total chlorophyll a (Tchl a)-specific absorption coefficient (aph*(λ)) were examined by the corresponding measurements of pigments identified by high-performance liquid chromatography. We observed distinct phytoplankton size structure and thereby absorption properties between ECS and TS. At the surface, mixed populations of micro-, nano- and pico-phytoplankton were recorded in ECS while pico-phytoplankton dominated in TS, generating a lower average aph*(λ) in ECS than in TS. Within SCM, average aph*(λ) was higher in ECS than in TS because of the dominance of nano- and micro-phytoplankton in ECS and TS, respectively. By pooling surface and SCM samples, we found regular trends in phytoplankton size-fraction versus Tchl a; and correlations between aph*(λ) and Tchl a consistent with previous observations for the global ocean in TS but not in ECS. In ECS phytoplankton size-fraction was not correlated with Tchl a, which consequently caused poor relationships between aph*(λ) and Tchl a. The abnormal values mainly originated from the surface low-salinity waters and SCM waters beneath them. At high Tchl a, aph*(λ) of these samples was substantially higher compared to the values in TS and from the global regressions, which was attributable to the lower micro-phytoplankton fraction, and higher nano- and/or pico-phytoplankton fractions in ECS. These observations indicated that the distinct light absorption properties of phytoplankton in ECS were possibly influenced by the Changjiang discharge. Our findings imply that general bio-optical algorithms proposed based on the correlations between aph*(λ) and Tchl a or the patterns in size-fraction versus Tchl a are not applicable in ECS, and need to be carefully considered when using these general algorithms in river-influenced regions.
Influence of snow depth distribution on surface roughness in alpine terrain: a multi-scale approach
Authors: Veitinger J. , Sovilla B. , Purves R. S.
Published: April 2014

Abstract. In alpine terrain, the snow-covered winter surface deviates from its underlying summer terrain due to the progressive smoothing caused by snow accumulation. Terrain smoothing is believed to be an important factor in avalanche formation and avalanche dynamics, and it affects surface heat transfer, energy balance as well as snow depth distribution. To assess the effect of snow on terrain, we use an adequate roughness definition. We developed a method to quantify terrain smoothing by combining roughness calculations of snow surfaces and their corresponding underlying terrain with snow depth measurements. To this end, elevation models of winter and summer terrain in three selected alpine basins in the Swiss Alps characterized by low, medium and high terrain roughness were derived from high-resolution measurements performed by airborne and terrestrial lidar. The preliminary results in the selected basins reveal that, at basin scale, terrain smoothing depends not only on mean snow depth in the basin but also on its variability. The multi-temporal analysis over three winter seasons in one basin suggests that terrain smoothing can be modelled as a function of mean snow depth and its standard deviation using a power law. However, a relationship between terrain smoothing and snow depth was not found at pixel scale. Further, we show that snow surface roughness is to some extent persistent, even in-between winter seasons. Those persistent patterns might be very useful to improve the representation of a winter terrain without modelling of the snow cover distribution. This can for example improve avalanche release area definition and, in the long term, natural hazard management strategies.
Benjamin, Dante, and the Modernity of the Middle Ages; or, Allegory as Urban Constellation
Authors: Knapp Ethan
Published: April 2014

This article interrogates the categories of modernity and allegory in Walter Benjamin's work. It contrasts the treatment of Baudelaire (the archetypical poet of modernity) in Benjamin's short essay “On Some Motifs in Baudelaire” with the treatment found in his Arcades Project, championing the more complex sense of allegory in the later work. It argues further that Benjamin's sense of allegory in this text is bound to the specific urban experience of the crowd, and that the association of allegory with urban crowds leads Benjamin to discover this constellation in both medieval and modern allegorical representations. The article ends with a reading of Dante's Vita Nuova.
Spinning-off or Licensing?
Authors: Uctu Ramazan , Jafta Rachel
Published: April 2014

Different mechanisms are available when universities embark on technology transfer to the private sector. This paper focuses on the option of intellectual property licensing of technologies. In particular, the authors examine why academics who are in a position to create a spin-off opt for licensing, in the context of the universities' rationale for technology transfer, the nature and performance of their technology transfer institutions and the motivations behind the academics' decisions. The case study focuses on South Africa's two oldest and premier research-led universities, based in the Western Cape region. The results show that technologies originated mainly from the engineering and health sciences and the biotechnology industries; technologies were created through collaboration among researchers; they were mainly patented worldwide; and the researchers chose to license the technology in order to convert their knowledge into practical applications, to use existing knowledge fully and to make a financial profit. The most important factors influencing the decision of an inventor/researcher not to create a spin-off company were funding, commercialization and distribution.
Bill Malone, Alan Lomax, and the Origins of Country Music
Authors: Cohen Ronald D.
Published: April 2014

Bill Malone has rightly been known as the dean of country music historians, beginning with the publication of Country Music U.S.A. in 1968. Malone has continually argued that country music had its beginnings in the South and has long remained basically a regional musical style. It is not clear, however, if this should be assumed, since vernacular music, perhaps a better term, has always existed nationwide. This essay makes the argument that studies of country music should take a national approach, focusing in particular on the northern collecting trips of Alan Lomax and numerous other folklorists and scholars, as well as the work of various musicians, including Paul Clayton. Future studies, therefore, should not take the southern focus for granted but should assume a countrywide approach.
Hillbilly Music Re-imagined: Folk and Country Music in the Midwest
Authors: Tyler Paul L.
Published: April 2014

Beginning in the 1960s, country music scholarship focused on the hillbilly image to advance a sectional claim to represent the history of the genre. In fact, the earlier institutionalization of country music, particularly in radio broadcasts, emerged from a wider swath of regional and ethnic folk music. Here the hillbilly is re-imagined to encompass a larger pool of folk musicians whose practices resided beyond the control of the musical establishment of the 1920s.
Doing What’s Right for the Baby: Parental Responses and Custodial Grandmothers’ Institutional Decision Making
Authors: Pittman LaShawnDa
Published: April 2014

Recent changes in kinship care policy produce a range of care-types for grandparents raising their grandchildren, from informal kinship care to adoption. The unprecedented formalization of kinship care, expedited termination of parental rights, and conflict between parents and grandparents over the best interests of children require custodial grandparents to make determinations about care-type, termed "institutional decision making." Interview data collected from 50 black custodial grandmothers from Chicago are used to reveal how and why parental responses help explain variation in care-types. This article argues that institutional decisions enable custodial grandmothers to achieve family stability by offering them an opportunity to be a safety net of protection to grandchildren, to respond to a range of parental responses that emerge as they work to eradicate child welfare threats, and to navigate institutions. The present study shows that, as parental responses increase in uncertainty and noncompliance, care-types become more formalized.
Invariance, Conservation Laws, and Exact Solutions of the Nonlinear Cylindrical Fin Equation
Authors: Ali Saeed M. , Bokhari Ashfaque H. , Zaman Fiazuddin D. , Kara Abdul H.
Published: April 2014

Fins are heat exchange surfaces which are used widely in industry. The partial differential equation arising from heat transfer in a fin of cylindrical shape with temperature dependent thermal diffusivity are studied. The method of multipliers and invariance of the differential equations is employed to obtain conservation laws and perform double reduction.
DNA polymerase V activity is autoregulated by a novel intrinsic DNA-dependent ATPase
Authors: Erdem Aysen L , Jaszczur Malgorzata , Bertram Jeffrey G , Woodgate Roger , Cox Michael M , Goodman Myron F
Published: April 2014

Escherichia coli DNA polymerase V (pol V), a heterotrimeric complex composed of UmuD′2C, is marginally active. ATP and RecA play essential roles in the activation of pol V for DNA synthesis including translesion synthesis (TLS). We have established three features of the roles of ATP and RecA. (1) RecA-activated DNA polymerase V (pol V Mut), is a DNA-dependent ATPase; (2) bound ATP is required for DNA synthesis; (3) pol V Mut function is regulated by ATP, with ATP required to bind primer/template (p/t) DNA and ATP hydrolysis triggering dissociation from the DNA. Pol V Mut formed with an ATPase-deficient RecA E38K/K72R mutant hydrolyzes ATP rapidly, establishing the DNA-dependent ATPase as an intrinsic property of pol V Mut distinct from the ATP hydrolytic activity of RecA when bound to single-stranded (ss)DNA as a nucleoprotein filament (RecA*). No similar ATPase activity or autoregulatory mechanism has previously been found for a DNA polymerase.
Analysis of the quadratic retardation induced by the Pockels, Kerr, and inverse piezoelectric effects in an X-cut Y-propagation LiNbO3
Authors: Takizawa Kuniharu , Haraguchi Koshi , Jin Lianhua , Suzuki Seiichi
Published: April 2014

In our previous work, we measured the Pockels coefficient r
51 of LiNbO3 crystal using two different methods. In one method, quadratic retardation was measured by neglecting the Kerr and inverse piezoelectric effects. In the other method, linear retardation was obtained without being affected by the Kerr effect. From the analysis of the results of these measurements by considering the Pockels, Kerr, and inverse piezoelectric effects on the retardation of the LiNbO3 crystal, the Kerr coefficient, which was previously unknown, was derived as g
31 = +0.188. The r
51 obtained from the quadratic retardation showed that the influence of the Kerr effect on the measurement of r
51 was approximately 0.4%. These results also indicate that the ratio of the Kerr coefficients g
31/g
11 can be approximated using the third power of the ordinary index of refraction divided by the extraordinary index of refraction.