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Kinds of Electric Terms modified by Electric Selected AbstractsDownsizing: The cure that can killGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 6 2009William F. Roth In a tough economy, many U.S. businesses turn to downsizing as a quick cost-cutting strategy. The author argues that the price isn't worth it, and that operational effectiveness, not efficiency, is the key to survival. The author discusses the systemic effects of downsizing and the impact on longer-term productivity. He cites alternatives to downsizing taken by Nugget Market, Dorner Mfg. Corp., and Lincoln Electric and then explores the case of an organization that rejected layoffs and instead utilized all its employees' expertise to design and implement improvements that produced increased productivity, revenue growth, and higher profitability. © 2009 Wiley Periodicals, Inc. [source] Currents: Books in BriefGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 3 2001LaRoi Lawton The Roots and Future of Management Theory Profit From the Core: Growth Strategy in an Era of Turbulence 90 Days to Launch: Internet Projects on Time and on Budget The Six Sigma Revolution: How General Electric and Others Turned Process into Profits In Good Company Evolve! Succeeding in the Digital Culture of Tomorrow Lessons from the Heart of American Business: A Roadmap for Managers in the 21st Century The Passion Plan at Work: A Step-by-Step Guide to Building a Passion-Driven Organization The Inner Work of Leaders: Leadership as a Habit of Mind Corporate Sin: Leaderless Leadership and Dissonant Workers The HR Scorecard Place to Space: Migrating to Ebusiness Models Building the Integrated Company Protecting Your Company's Intellectual Property: A Practical Guide to Trademarks, Copyrights, Patents, & Trade Secrets Gaming the System: Stop Playing the Organizational Game [source] INVESTOR RELATIONS, LIQUIDITY, AND STOCK PRICESJOURNAL OF APPLIED CORPORATE FINANCE, Issue 4 2000Michael J. Brennan Although the first investor relations department was established by General Electric as long ago as 1952, the role of investor relations (IR) is one that has largely escaped scientific analysis and academic scrutiny. This article attempts to demonstrate the importance of a company's IR activities for its stock price by establishing a clear chain of causation between the following: 1,corporate IR activities and the number of stock analysts who follow the firm; 2,the number of analysts who follow the firm and the liquidity of trading in the firm's shares; 3,the liquidity of the firm's shares and its required rate of return, or cost of capital. The authors begin by presenting evidence that corporate IR activities, in the form of high levels of disclosure and presentations to investment analysts, increase the number of analysts who follow the firm by reducing their cost of acquiring information. Studies have also shown that more effective IR tends to improve the accuracy of analyst forecasts and the degree of agreement among analysts. Second, the authors summarize their own research showing that the number of analysts who follow a firm has a positive effect on the liquidity of the firm's shares. More specifically, their findings can be interpreted as saying that, for the average company, coverage by six additional analysts reduces "market-impact costs" (using a measure known as Kyle's lambda) by 28%, holding volume constant. And when the indirect effect of increased analyst coverage through expanded volume is taken into account, the reduction in trading costs is estimated to be as high as 85%. The final link in the chain of analysis is the growing evidence (much of it reviewed in the preceding article) that increased liquidity leads to a lower cost of capital and thus higher stock prices. In sum, a firm can reduce its cost of capital and increase its stock price through more effective investor relations activities, which reduce the cost of information to the market and to investment analysts in particular. [source] Internal Thoracic Arterial Grafts Evaluation by Multislice CT Scan:JOURNAL OF CARDIAC SURGERY, Issue 6 2004A Preliminary Study The aim of this study is to evaluate the multidetector multislice CT Scan (MCTS) as a means of postoperative evaluation of ITA coronary artery bypass grafts. Methods: Twenty-eight patients having been operated on for coronary artery bypass with ITA during a 6-months period, benefited, 7 days after surgery, from a patency and anastomotic site control of ITA with a MCTS associated with cardiac gating (Light Speed, General Electric, USA). Results: Internal thoracic artery bypasses are visualized perfectly on all their courses, with possibility of 3D reconstructions, showing the relationship between cardiac cavities and the arterial bypasses. The anastomotic site on the LAD was, in selected cases, perfectly visualized. Sequential bypasses with left ITA are well visualized as well as T or Y right-to-left ITA grafts. However, surgical clips create some image artefacts. Conclusions: The postoperative control of ITAs are possible by MCTS with a satisfactory resolution. This makes it possible to check the patency of ITAs, their course on the heart surface, and the location and quality of anastomosis with a noninvasive reproductive method. [source] Amersham radiochemistry to GE Healthcare,JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 9-10 2007Sean L. Kitson Abstract I was invited by Professor John R. Jones (University of Surrey) to write a paper to celebrate 50 years of the Journal of Labelled Compounds and Radiopharmaceuticals. The aim of this paper is to outline briefly the history of radiochemistry from The Radiochemical Centre at Amersham in the 1940s to the acquisition by General Electric in 2004 and the formation of GE Healthcare. Copyright © 2007 John Wiley & Sons, Ltd. [source] Estrogen as a neuroprotective agent in rat spinal cord injuryJOURNAL OF NEUROCHEMISTRY, Issue 2002N. L. Banik Spinal cord injury (SCI) is a neurological problem affecting approximately 11 000 Americans each year. Several treatment agents have been proposed; however, only methylprednisolone has limited efficacy. Estrogen is a multiactive neuroprotectant with antioxidant and anti-inflammatory properties and attenuates calcium (Ca2+) influx following neuronal injury. To examine the neuroprotective effects of estrogen in SCI, we induced SCI (40 g/cm injury) in rats. Treatment groups were sham (laminectomy only), SCI plus vehicle, and SCI plus estrogen. Injured rats were treated with either 4 mg/kg 17 ,-estradiol (estrogen group) or dimethylsulfoxide (vehicle group) at 15 min and 24 h following injury. All rats were killed at 48 h to analyze SCI segments for calpain content and Bax/Bcl-2 ratio by Western blotting. Tissue was also examined using calcium green-2 to measure intracellular [Ca2+], JC-1 to measure mitochondrial membrane potential, and double immunofluorescence for macrophages and calpain. Calpain content in the lesion penumbra, adjacent to the injury, was higher in vehicle than sham and this increase was attenuated in estrogen treated rats. In the lesion penumbra, the Bax/Bcl-2 ratio was increased in vehicle rats as compared to sham. This increase was attenuated in estrogen treated rats. Estrogen treated rats had less Ca2+ influx, less inflammatory cell infiltration, and increased maintenance of mitochondrial membrane potential compared to vehicle treated rats. Our preliminary data suggest that estrogen may be effective in decreasing Ca2+ influx, inflammatory cell infiltration, and Bax/Bcl-2 ratio following SCI. Acknowledgements:, Supported in part by grants from NIH-NINDS and South Carolina Electric and Gas. [source] Electric and Dielectric Behaviors of Y-Doped Calcium Copper TitanateJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2010Fengchao Luo Yttrium-doped CaCu3Ti4,xYxO12,x/2 (x=0,0.1) samples were fabricated by using solid-state sintering, and their electric and dielectric properties were investigated. Yttrium addition has shown to reduce the dielectric loss remarkably while maintaining colossal permittivity. At x=0.5, the loss (tan ,) is below 0.1 over the frequency range from 1 to 300 KHz, while that of the pure ceramic is above 0.1 over most measuring frequency range. The current density,electric field curves proved that yttrium doping can effectively enhance the varistor voltage, indicating a rise of the potential barrier height at the grain boudaries. Local measurement of impedance at the grain boundaries was performed by using microcontact probes. The results indicated that yttrium dramatically increases the resistance of the grain boundaries. The differences are attributed to the enhanced Cu segregation at grain boundaries, which is induced by yttrium doping. [source] Electric and Dielectric Properties of Nb-Doped CaCu3Ti4O12 CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2007Seong-Hyeon Hong Pure and Nb-substituted CaCu3Ti4,xNbxO12+x/2 (CCTO, x=0, 0.02, 0.1, 0.2, 0.4) ceramics were prepared by a conventional solid-state sintering, and their electric and dielectric properties were investigated using an impedance analyzer. A single-phase CCTO was obtained up to x=0.2 Nb substitution and the lattice parameter increased with Nb substitution concentration. While the grain size decreased with Nb substitution, the resistivity of the grain boundary decreased. The dielectric constant increased with Nb substitution, and the highest value of ,420 000 was observed in the x=0.2 Nb-substituted specimen at 10 kHz. The obtained electric and dielectric properties in Nb-substituted CCTO were discussed in terms of the internal barrier layer capacitor model, particularly focusing on a ratio of thickness of the grain boundary region to grain size. [source] Implementation of three-dimensional wavelet encoding spectroscopic imaging: In vivo application and method comparisonMAGNETIC RESONANCE IN MEDICINE, Issue 1 2009Richard Young Abstract We have recently proposed a two-dimensional Wavelet Encoding-Spectroscopic Imaging (WE-SI) technique as an alternative to Chemical Shift Imaging (CSI), to reduce acquisition time and crossvoxel contamination in magnetic resonance spectroscopic imaging (MRSI). In this article we describe the extension of the WE-SI technique to three dimensions and its implementation on a clinical 1.5 T General Electric (GE) scanner. Phantom and in vivo studies are carried out to demonstrate the usefulness of this technique for further acquisition time reduction with low voxel contamination. In wavelet encoding, a set of dilated and translated prototype functions called wavelets are used to span a localized space by dividing it into a set of subspaces with predetermined sizes and locations. In spectroscopic imaging, this process is achieved using radiofrequency (RF) pulses with profiles resembling the wavelet shapes. Slice selective excitation and refocusing RF pulses, with single-band and dual-band profiles similar to Haar wavelets, are used in a modified PRESS sequence to acquire 3D WE-SI data. Wavelet dilation and translation are achieved by changing the strength of the localization gradients and frequency shift of the RF pulses, respectively. The desired spatial resolution in each direction sets the corresponding number of dilations (increases in the localization gradients), and consequently, the number of translations (frequency shift) of the Haar wavelets (RF pulses), which are used to collect magnetic resonance (MR) signals from the corresponding subspaces. Data acquisition time is reduced by using the minimum recovery time (TRmin), also called effective time, when successive MR signals from adjacent subspaces are collected. Inverse wavelet transform is performed on the acquired data to produce metabolite maps. The proposed WE-SI method is compared in terms of acquisition time, pixel bleed, and signal-to-noise ratio to the CSI technique. The study outcome shows that 3D WE-SI provides accurate results while reducing both acquisition time and voxel contamination. Magn Reson Med 61:6,15, 2009. © 2008 Wiley-Liss, Inc. [source] A study of the relationship between the seizure focus and 1H-MRS in temporal lobe epilepsy and frontal lobe epilepsyPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2000Senichiro Kikuchi MD Abstract Several studies of temporal lobe epilepsy (TLE) patients have investigated the relationship between the seizure focus and 1H magnetic resonance spectroscopy (1H-MRS). There have also been a few reports in other types of partial epilepsy. We examined the relationship between the seizure focus and the reduction in N -acetylaspartate : creatine (NAA : Cr) ratio using 1H-MRS in both TLE and frontal lobe epilepsy (FLE) patients. We studied 21 patients with unilateral TLE and seven patients with unilateral FLE. We used a 1.5 Tesla magnetic resonance unit (Signa Horizon; General Electric). Approximately 15 × 15 × 20 mm3 voxel of interest (VOI) was placed over the anterior portion of the bilateral hippocampus in the TLE patients, and the anterodorsal position of bilateral frontal lobe in the FLE patients. The seizure focus was identified by interictal scalp electro-encephalogram (EEG). In the TLE patients the NAA : Cr ratios were reduced in the seizure focus, while in the FLE patients they were not always reduced in the seizure focus. In the TLE patients the coincidence rate between the seizure focus and the reduction in the NAA : Cr ratio was 90% (19 of 21 patients), while in the FLE patients the coincidence rate was only 57% (four of seven patients). [source] Leading Business Improvement: a New Role for Statisticians and Quality ProfessionalsQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 3 2005Ronald D. Snee Abstract Following the successes of Motorola, Allied-Signal, General Electric and others, many companies are implementing the Six Sigma approach to business improvement. Millions of dollars are being saved in the process. Active leadership by management and others involved is integral to the method and critical to its success. This development provides a unique opportunity for statisticians and quality professionals to be leaders in their organizations. The leadership roles are discussed and it is shown how statisticians and quality professionals can assume leadership roles throughout the deployment process. As a result statisticians and quality professionals can expand their roles as internal trainers and consultants to include being leaders of business improvement. In the process their focus moves from facilitation of technical applications to the implementation of Six Sigma, skill deployment and delivery of bottom line business results. Copyright © 2005 John Wiley & Sons, Ltd. [source] Extremely low frequency (ELF) electric and magnetic field exposure limits: Rationale for basic restrictions used in the development of an Australian standard,BIOELECTROMAGNETICS, Issue 6 2008Andrew W. Wood Abstract There are large disparities between basic restrictions for exposure to extremely low-frequency (0,3 kHz) Electric and Magnetic Fields set by two major international bodies. Both bodies agree that these basic restrictions should prevent neuro-stimulatory effects: the retinal phosphene at frequencies up to a few hundred Hertz and peripheral nervous stimulation (PNS) at higher frequencies. The disparity arises from differences in estimated thresholds and frequency dependence, and whether restrictions should be of tissue induced current density or electric field. This paper argues that the latter metric more directly relates to neurostimulatory processes. By analysing available literature, a threshold for retinal phosphenes occurrence is found to be 56 mV/m (95% Confidence Interval 2,1330 mV/m), with a characteristic frequency of 20 Hz. Similarly, the smallest PNS sensation threshold is identified at 2 V/m (characteristic frequency above 3 kHz). In the case of the former, the large range of uncertainty suggests a ,power of ten' value of 100 mV/m. For the latter, because of the small margin between sensation and pain threshold, and because of the large individual variation, the smallest estimate of sensation threshold (2 V/m) represents a basic restriction with precaution incorporated. Bioelectromagnetics 29:414,428, 2008. © 2008 Wiley-Liss, Inc. [source] Chromosomal aberrations in lymphocytes of employees in transformer and generator production exposed to electromagnetic fields and mineral oilBIOELECTROMAGNETICS, Issue 3 2001Knut Skyberg Abstract The objective was to study the risk of cytogenetic damage among high voltage laboratory workers exposed to electromagnetic fields and mineral oil. This is a cross sectional study of 24 exposed and 24 matched controls in a Norwegian transformer factory. The exposure group included employees in the high voltage laboratory and in the generator soldering department. Electric and magnetic fields and oil mist and vapor were measured. Blood samples were analyzed for chromosomal aberrations in cultured lymphocytes. In addition to conventional cultures, the lymphocytes were also treated with hydroxyurea and caffeine. This procedure inhibits DNA synthesis and repair in vitro, revealing in vivo genotoxic lesions that are repaired during conventional culturing. In conventional cultures, the exposure group and the controls showed similar values for all cytogenetic parameters. In the DNA synthesis- and repair-inhibited cultures, generator welders showed no differences compared to controls. Among high voltage laboratory testers, compared to the controls, the median number of chromatid breaks was doubled (5 vs. 2.5 per 50 cells; P<0.05) the median number of chromosome breaks was 2 vs. 0.5 (P>0.05) and the median number of aberrant cells was 5 vs. 3.5 (P<0.05). Further analysis of the inhibited culture data from this and a previous study indicated that years of exposure and smoking increase the risk of aberrations. We conclude that there was no increase in cytogenetic damage among exposed workers compared to controls in the conventional lymphocyte assay. In inhibited cultures, however, there were indications that electromagnetic fields in combination with mineral oil exposure may produce chromosomal aberrations. Bioelectromagnetics 22:150,160, 2001. © 2001 Wiley-Liss, Inc. [source] From Edison To Immelt: The GE WayBUSINESS STRATEGY REVIEW, Issue 3 2009Stuart Crainer General Electric is one of the great corporations of our times. While others fall by the wayside, it has forged a uniquely strong corporate trajectory over more than a century. But what makes the giant tick? How has GE outlasted the competition and does it have the strength and sense of purpose to carry on?Stuart Crainer explores the GE way. [source] ChemInform Abstract: Rapid Synthesis of Bi and Sb Sulfides Using Electric Discharge Assisted Mechanical Milling.CHEMINFORM, Issue 30 2008A. Calka Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Multipolar Ordering in Electro- and Magnetostatic Coupled NanosystemsCHEMPHYSCHEM, Issue 9 2008Elena Y. Vedmedenko Dr. habil. Abstract Electric and magnetic multipole moments and polarizabilities are important quantities in studies of intermolecular forces, non-linear optical phenomena, electrostatic, magnetostatic or gravitational potentials and electron scattering. The experimental determination of multipole moments is difficult and therefore the theoretical prediction of these quantities is important. Depending on purposes of the investigation several different definitions of multipole moments and multipole,multipole interactions are used in the literature. Because of this variety of methods it is often difficult to use published results and, therefore, even more new definitions appear. The first goal of this review is to give an overview of mathematical definitions of multipole expansion and relations between different formulations. The second aim is to present a general theoretical description of multipolar ordering on periodic two-dimensional lattices. After a historical introduction in the first part of this manuscript the static multipole expansion in cartesian and spherical coordinates as well as existing coordinate transformations are reviewed. On the basis of the presented mathematical description multipole moments of several symmetric charge distributions are summarized. Next, the established numerical approach for the calculation of multipolar ground states, namely Monte Carlo simulations, are reviewed. Special emphasis is put on the review of ground states in multipolar systems consisting of moments of odd or even order. The last section is devoted to the magnetization reversal in dense packed nanomagnetic arrays, where the magnetic multipole,multipole interactions play an important role. Comparison between the theory and recent experimental results is given. [source] Orientation Ordering of Nanoparticle Ag/Co Cores Controlled by Electric and Magnetic FieldsCHEMPHYSCHEM, Issue 7 2008Katarína Gmucová Dr. Abstract The effect of electric and magnetic fields on the sandwich structure Pt/hydrogenated amorphous silicon (a-Si:H)/stearic acid monolayer/Langmuir,Blodgett film of Ag/Co nanoparticles encapsulated in an organic envelope is studied. This structure is used as a working electrode in an electrochemical cell filled with NaCl solution (1 mM) and equipped with an Ag/AgCl reference electrode. Reversible changes in voltammograms are observed due to treatments (negative or positive bias voltage and simultaneous laser irradiation) applied to the designed structure before measurements. As an explanation of the observed phenomena we suggest that both the Co-up and Ag-up (on the a-Si:H surface) orientation orderings of nanoparticle Ag/Co cores are repeatedly reached. The role of the photovoltaic material (a-Si:H) in the observed behavior is explained. Voltammetric measurements with an applied magnetic field support our idea about the orientation ordering of nanoparticle cores. [source] Elementary Many-Particle Processes in Plasma MicrofieldsCONTRIBUTIONS TO PLASMA PHYSICS, Issue 3 2006M. Yu. Abstract The effect of electric and magnetic plasma microfields on elementary many-body processes in plasmas is considered. As detected first by Inglis and Teller in 1939, the electric microfield controls several elementary processes in plasmas as transitions, line shifts and line broadening. We concentrate here on the many-particle processes ionization, recombination, and fusion and study a wide area of plasma parameters. In the first part the state of art of investigations on microfield distributions is reviewed in brief. In the second part, various types of ionization processes are discussed with respect to the influence of electric microfields. It is demonstrated that the processes of tunnel and rescattering ionization by laser fields as well as the process of electron collisional ionization may be strongly influenced by the electric microfields in the plasma. The third part is devoted to processes of microfield action on fusion processes and the effects on three-body recombination are investigated. It is shown that there are regions of plasma densities and temperatures, where the rate of nuclear fusion is accelerated by the electric microfields. This effect may be relevant for nuclear processes in stars. Further, fusion processes in ion clusters are studied. Finally we study in this section three-body recombination effects and show that an electric microfield influences the three-body electron-ion recombination via the highly excited states. In the fourth part, the distribution of the magnetic microfield is investigated for equilibrium, nonequilibrium, and non-uniform magnetized plasmas. We show that the field distribution in a neutral point of a non-relativistic ideal equilibrium plasma is similar to the Holtsmark distribution for the electrical microfield. Relaxation processes in nonequilibrium plasmas may lead to additional microfields. We show that in turbulent plasmas the broadening of radiative electron transitions in atoms and ions, without change of the principle quantum number, may be due to the Zeeman effect and may exceed Doppler and Stark broadening as well. Further it is shown that for optical radiation the effect of depolarization of a linearly polarized laser beams propagating through a magnetized plasma may be rather strong. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Decision Making in a Standby Service System,DECISION SCIENCES, Issue 3 2000H. V. Ravinder A standby service option allows a firm to lower its risk of not having sufficient capacity to satisfy demand without investing in additional capacity. Standby service options currently exist in the natural gas, electric, and water utility industries. Firms seeking standby service are typically large industrial or institutional organizations that, due to unexpectedly high demand or interruptions in their own supply system, look to a public utility to supplement their requirements. Typically, the firm pays the utility a reservation fee based on a nominated volume and a consumption charge based on the volume actually taken. In this paper, a single-period model is developed and optimized with respect to the amount of standby capacity a firm should reserve. Expressions for the mean and variance of the supplier's aggregate standby demand distribution are developed. A procedure for computing the level of capacity needed to safely meet its standby obligations is presented. Numerical results suggest that the standby supplier can safely meet its standby demand with a capacity that is generally between 20 to 50% of the aggregate nominated volume. [source] The dependence of the electrophoretic mobility of small organic ions on ionic strength and complex formationELECTROPHORESIS, Issue 5 2010Stuart A. Allison Abstract The ionic strength dependence of the electrophoretic mobility of small organic anions with valencies up to ,3 is investigated in this study. Provided the anions are not too aspherical, it is argued that shape and charge distribution have little influence on mobility. To a good approximation, the electrophoretic mobility of a small particle should be equal to that of a model sphere with the same hydrodynamic radius and same net charge. For small ions, the relaxation effect (distortion of the ion atmosphere from equilibrium due to external electric and flow fields) is significant even for monovalent ions. Alternative procedures of accounting for the relaxation effect are examined. In order to account for the ionic strength dependence of a specific set of nonaromatic and aromatic anions in aqueous solution, it is necessary to include complex formation between the anion with species in the BGE. A number of possible complexes are considered. When the BGE is Tris-acetate, the most important of these involves the complex formed between anion and Tris, the principle cation in the BGE. When the BGE is sodium borate, an anion,anion (borate) complex appears to be important, at least when the organic anion is monovalent. An algorithm is developed to analyze the ionic strength dependence of the electrophoretic mobility. This algorithm is applied to two sets of organic anions from two independent research groups. [source] Joule heating in electrokinetic flowELECTROPHORESIS, Issue 1 2008Xiangchun Xuan ProfessorArticle first published online: 30 NOV 200 Abstract Electrokinetic flow is an efficient means to manipulate liquids and samples in lab-on-a-chip devices. It has a number of significant advantages over conventional pressure-driven flow. However, there exists inevitable Joule heating in electrokinetic flow, which is known to cause temperature variations in liquids and draw disturbances to electric, flow and concentration fields via temperature-dependent material properties. Therefore, both the throughput and the resolution of analytic studies performed in microfluidic devices are affected. This article reviews the recent progress on the topic of Joule heating and its effect in electrokinetic flow, particularly the theoretical and experimental accomplishments from the aspects of fluid mechanics and heat/mass transfer. The primary focus is placed on the temperature-induced flow variations and the accompanying phenomena at the whole channel or chip level. [source] Sing the mind electric , principles of deep brain stimulationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2010Morten L. Kringelbach Abstract The remarkable efficacy of deep brain stimulation (DBS) for a range of treatment-resistant disorders is still not matched by a comparable understanding of the underlying neural mechanisms. Some progress has been made using translational research with a range of neuroscientific techniques, and here we review the most promising emerging principles. On balance, DBS appears to work by restoring normal oscillatory activity between a network of key brain regions. Further research using this causal neuromodulatory tool may provide vital insights into fundamental brain function, as well as guide targets for future treatments. In particular, DBS could have an important role in restoring the balance of the brain's default network and thus repairing the malignant brain states associated with affective disorders, which give rise to serious disabling problems such as anhedonia, the lack of pleasure. At the same time, it is important to proceed with caution and not repeat the errors from the era of psychosurgery. [source] On the attempts to optimize the performance and cost-effectiveness of TFPM drives: a crucial challenge for the automotive industryEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 6 2005Ahmed Masmoudi Much attention is currently focused upon transverse flux permanent magnet machines (TFPMs), especially in automotive applications, in so far as, to date, they exhibit the highest power production capability. Different automotive manufacturers are currently involved in R&D programs dealing with TFPM concepts and the possibilities of their integration in electric and hybrid propulsion systems. This paper is devoted to the analysis of two R&D projects developed within the design of TFPMs intended for hybrid propulsion systems of heavy-duty vehicles. In spite of the increasing interest in TFPMs and the significant improvements brought to their earlier topologies, we can firmly state that further investigations remain to be carried out before the TFPM concepts could be regarded as a mature technology for the automotive industry. Copyright © 2005 John Wiley & Sons, Ltd. [source] Mitigation of the produced voltages in AC overhead power-lines/pipelines parallelism during power frequency and lightning conditionsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2005I. A. Metwally Abstract This paper presents a theoretical simulation for a pipeline running in parallel to AC overhead power lines using the ,CONCEPT II' package. This package is based on the method of moment combined with a transmission-line model. A 1,km long, 132,kV, three-phase, double-circuit transmission line, and a 2,km long, 40,cm diameter, 1,m high above-ground pipeline are modelled. Extra shielding wires (ESW) under the phase conductors are investigated. Produced voltages in the pipeline are computed under steady-state power frequency (50,Hz) as well as under direct and indirect lightning strikes to the power line. Different current waveforms are simulated to cover the whole range of those of the anticipated lightning. Under lightning strikes, the voltages across line insulators are computed, too. The results reveal that the ESW give many advantages; namely, (1) reducing the power-frequency electric and magnetic fields at the ground level to meet the regularity limits, (2) improving the shielding effectiveness during lightning strikes by reducing the insulator voltages, (3) mitigating the induced voltages in any metallic structure near the power lines, e.g., pipelines, and (4) using them as optical ground wires for telecommunication purposes, where the probability of lightning strikes to such ESW is much lower than that for the normally used grounding wire(s) at the tower top. Copyright © 2005 John Wiley & Sons, Ltd. [source] Tunable Colors in Opals and Inverse Opal Photonic CrystalsADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Carlos I. Aguirre Abstract Colloidal photonic crystals and materials derived from colloidal crystals can exhibit distinct structural colors that result from incomplete photonic band gaps. Through rational materials design, the colors of such photonic crystals can be tuned reversibly by external physical and chemical stimuli. Such stimuli include solvent and dye infiltration, applied electric or magnetic fields, mechanical deformation, light irradiation, temperature changes, changes in pH, and specific molecular interactions. Reversible color changes result from alterations in lattice spacings, filling fractions, and refractive index of system components. This review article highlights the different systems and mechanisms for achieving tunable color based on opaline materials with close-packed or non-close-packed structural elements and inverse opal photonic crystals. Inorganic and polymeric systems, such as hydrogels, metallopolymers, and elastomers are discussed. [source] The use of fyke nets as a quantitative capture technique for freshwater eels (Anguilla spp.) in riversFISHERIES MANAGEMENT & ECOLOGY, Issue 4 2005D. J. JELLYMAN Abstract, Fyke netting is a convenient and effective technique for capturing freshwater eels, and catch-per-unit-effort is usually assumed to be an index of eel abundance. The present study investigated the potential of depletion fishing using baited fyke nets to obtain population estimates of longfin eels Anguilla dieffenbachii Gray, in a river in the South Island of New Zealand. The probability of capture (capture efficiency) of a single night's fishing increased with increasing size of eel, and ranged from 0.2 to 0.9 for eels <400 mm, to 0.7,0.9 for eels ,500 mm. The capture efficiency of baited vs unbaited nets was assessed in a small stream that was electric fished after netting trials were completed. Baited nets proved to be an effective method of assessing abundance of longfin eels (>400 mm) but not shortfins (A. australis Richardson); capture efficiency of the population of longfins (the sum of fyke caught and electric fished eels) was 0.4 for a single night's fyke netting, increasing to 0.8 over four nights. Comparable efficiencies for shortfins were <0.1 and 0.3 respectively. Unbaited nets were markedly less efficient for both species. [source] Electric/magnetic deformations of S3 and AdS3, and geometric cosets,FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 1 2005D. Israël We analyze asymmetric marginal deformations of SU(2)k and SL(2,,)k WZW models. These appear in heterotic string backgrounds with non-vanishing Neveu,Schwarz three-forms plus electric or magnetic fields, depending on whether the deformation is elliptic, hyperbolic or parabolic. Asymmetric deformations create new families of exact string vacua. The geometries which are generated in this way, deformed S3 or AdS3, include in particular geometric cosets such as S2, AdS2 or H2. Hence, the latter are consistent, exact conformal sigma models, with electric or magnetic backgrounds. We discuss various geometric and symmetry properties of the deformations at hand as well as their spectra and partition functions, with special attention to the supersymmetric AdS2 × S2 background. We also comment on potential holographic applications. [source] An ellipticity criterion in magnetotelluric tensor analysisGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2004M. Becken SUMMARY We examine the magnetotelluric (MT) impedance tensor from the viewpoint of polarization states of the electric and magnetic field. In the presence of a regional 2-D conductivity anomaly, a linearly polarized homogeneous external magnetic field will generally produce secondary electromagnetic fields, which are elliptically polarized. If and only if the primary magnetic field vector oscillates parallel or perpendicular to the 2-D structure, will the horizontal components of the secondary fields at any point of the surface also be linearly polarized. When small-scale inhomogeneities galvanically distort the electric field at the surface, only field rotations and amplifications are observed, while the ellipticity remains unchanged. Thus, the regional strike direction can be identified from vanishing ellipticities of electric and magnetic fields even in presence of distortion. In practice, the MT impedance tensor is analysed rather than the fields themselves. It turns out, that a pair of linearly polarized magnetic and electric fields produces linearly polarized columns of the impedance tensor. As the linearly polarized electric field components generally do not constitute an orthogonal basis, the telluric vectors, i.e. the columns of the impedance tensor, will be non-orthogonal. Their linear polarization, however, is manifested in a common phase for the elements of each column of the tensor and is a well-known indication of galvanic distortion. In order to solve the distortion problem, the telluric vectors are fully parametrized in terms of ellipses and subsequently rotated to the coordinate system in which their ellipticities are minimized. If the minimal ellipticities are close to zero, the existence of a (locally distorted) regional 2-D conductivity anomaly may be assumed. Otherwise, the tensor suggests the presence of a strong 3-D conductivity distribution. In the latter case, a coordinate system is often found, in which three elements have a strong amplitude, while the amplitude of the forth, which is one of the main-diagonal elements, is small. In terms of our ellipse parametrization, this means, that one of the ellipticities of the two telluric vectors approximately vanishes, while the other one may not be neglected as a result of the 3-D response. The reason for this particular characteristic is found in an approximate relation between the polarization state of the telluric vector with vanishing ellipticity and the corresponding horizontal electric field vector in the presence of a shallow conductive structure, across which the perpendicular and tangential components of the electric field obey different boundary conditions. [source] Orientational Switching of Mesogens and Microdomains in Hydrogen-Bonded Side-Chain Liquid-Crystalline Block Copolymers Using AC Electric Fields ,ADVANCED FUNCTIONAL MATERIALS, Issue 4 2004C.-Y. Chao Abstract In this report, we show that the microstructures of hydrogen-bonded side-chain liquid-crystalline block copolymers can be rapidly aligned in an alternating current (AC) electric field at temperatures below the order,disorder transition but above the glass transition. The structures and their orientation were measured in real time with synchrotron X-ray scattering. Incorporation of mesogenic groups with marked dipolar properties is a key element in this process. A mechanism related to the dissociation of hydrogen bonds is proposed to account for the fast orientation switching of the hydrogen-bonded blends. [source] Well-Defined Fullerene Nanowire Arrays,ADVANCED FUNCTIONAL MATERIALS, Issue 8 2003Y.-G. Guo Abstract Fullerene nanowire arrays with well-defined size and length have been prepared by a controllable technique. Fullerene molecules such as C60 are introduced into the pores of anodic aluminum oxide (AAO) templates under a direct current (DC) electric field and polymerized in the pores. Structure analysis shows that the C60 nanowires are mainly polycrystalline, and a rhombohedral polymeric phase is observed in their vibration spectra. The electrical conductivity of so-prepared nanowire arrays show a semiconducting behavior. The ability to fabricate the fullerene nanowire arrays with controlled structures represents an important step toward the development of chemical sensors and nanoscale electronic devices based on fullerenes. [source] | ||||||||||||||||||||||||||||||||||