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Sample records for brain-controlled functional electrical

  1. Toward the restoration of hand use to a paralyzed monkey: brain-controlled functional electrical stimulation of forearm muscles.

    Directory of Open Access Journals (Sweden)

    Eric A Pohlmeyer

    Full Text Available Loss of hand use is considered by many spinal cord injury survivors to be the most devastating consequence of their injury. Functional electrical stimulation (FES of forearm and hand muscles has been used to provide basic, voluntary hand grasp to hundreds of human patients. Current approaches typically grade pre-programmed patterns of muscle activation using simple control signals, such as those derived from residual movement or muscle activity. However, the use of such fixed stimulation patterns limits hand function to the few tasks programmed into the controller. In contrast, we are developing a system that uses neural signals recorded from a multi-electrode array implanted in the motor cortex; this system has the potential to provide independent control of multiple muscles over a broad range of functional tasks. Two monkeys were able to use this cortically controlled FES system to control the contraction of four forearm muscles despite temporary limb paralysis. The amount of wrist force the monkeys were able to produce in a one-dimensional force tracking task was significantly increased. Furthermore, the monkeys were able to control the magnitude and time course of the force with sufficient accuracy to track visually displayed force targets at speeds reduced by only one-third to one-half of normal. Although these results were achieved by controlling only four muscles, there is no fundamental reason why the same methods could not be scaled up to control a larger number of muscles. We believe these results provide an important proof of concept that brain-controlled FES prostheses could ultimately be of great benefit to paralyzed patients with injuries in the mid-cervical spinal cord.

  2. Functional electrical stimulation with surface electrodes

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    Bajd Tadej

    2008-01-01

    Full Text Available The review investigates the objective evidences of benefits derived from surface functional electrical stimulation (FES of lower and upper extremities for people after incomplete spinal cord injury (SCI and stroke. FES can offer noticeable benefits in walking ability. It can be efficiently combined with treadmill and body weight support. Voluntary muscle strength and endurance gain can be achieved through FES assisted gait training together with increased gait velocity in absence of electrical stimulator. Cyclic FES, FES augmented by biofeedback, and FES used in various daily activities can result in substantial improvements of the voluntary control of upper extremities.

  3. Artifacts of Functional Electrical Stimulation on Electromyograph

    Institute of Scientific and Technical Information of China (English)

    DUAN Ren-quan; ZHANG Ding-guo

    2014-01-01

    The purpose of this study is to investigate different factors of the artifact in surface electromyography (EMG) signal caused by functional electrical stimulation (FES). The factors investigated include the size of stimulation electrode pads, the amplitude, frequency, and pulse width of the stimulation waveform and the detecting electrode points. We calculate the root mean square (RMS) of EMG signal to analyze the effect of these factors on the M-wave properties. The results indicate that the M-wave mainly depends on the stimulation amplitude and the distribution of detecting electrodes, but not on the other factors. This study can assist the reduction of artifact and the selection of detecting electrode points.

  4. Functional Electrical Stimulation in Children and Adolescents with Cerebral Palsy

    Science.gov (United States)

    van der Linden, Marietta

    2012-01-01

    In this article, the author talks about functional electrical stimulation in children and adolescents with cerebral palsy. Functional electrical stimulation (FES) is defined as the electrical stimulation of muscles that have impaired motor control, in order to produce a contraction to obtain functionally useful movement. It was first proposed in…

  5. Technical Rebuilding of Movement Function Using Functional Electrical Stimulation

    Science.gov (United States)

    Gföhler, Margit

    To rebuild lost movement functions, neuroprostheses based on functional electrical stimulation (FES) artificially activate skeletal muscles in corresponding sequences, using both residual body functions and artificial signals for control. Besides the functional gain, FES training also brings physiological and psychological benefits for spinal cord-injured subjects. In this chapter, current stimulation technology and the main components of FES-based neuroprostheses including enhanced control systems are presented. Technology and application of FES cycling and rowing, both approaches that enable spinal cord-injured subjects to participate in mainstream activities and improve their health and fitness by exercising like able-bodied subjects, are discussed in detail, and an overview of neuroprostheses that aim at restoring movement functions for daily life as walking or grasping is given.

  6. Wireless distributed functional electrical stimulation system

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    Jovičić Nenad S

    2012-08-01

    Full Text Available Abstract Background The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. Methods The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype’s software. Results The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers. One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. Conclusions The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  7. Protes Electrical Functional Chain: Flight Return Experience

    Science.gov (United States)

    Cresp, Jean-Michel; Boutelet, Eric; Massot, Jean; Tastet, Pierre

    2011-10-01

    Proteus is a multi-mission bus concept developed in partnership by Thales Alenia Space (France) and CNES (France). The first application of this platform was Jason1, an oceanography satellite launched in December 2001. Later on, led by the need for extra power for the next Proteus missions, the initial electrical functional chain has been modified by the replacement of the previous Nickel-Cadmium battery by a Lithium-ion one, baseline of the new Proteus 5PF platform. The Proteus electrical functional chain is based on the use of a single battery, permanently connected to the main bus. Its charge is ensured by the on-board software, which adapts the number of solar sections connected the bus. Due to the LEO orbits (700 Km for CALIPSO), the battery is submitted to a high number of cycles (typically 25500 cycles for Calipso). Roughly, a 78Ah nameplate battery, coupled to a solar array delivering 1KW, are able to supply a payload with a power demand up to 600W, for a lifetime higher than three years, under LEO environment. In 2006, on April 28th, the French-American CALIPSO satellite mission has been successfully launched. The CALIPSO mission, project involving NASA (US), CNES (France) and the Institut Pierre-Simon Laplace (CNRS, France), is the first satellite using the Proteus 5PF. CALIPSO provides 3D perspectives of clouds and Aerosols. The second Proteus 5PF mission, the space telescope COROT, has been launched in 2006, on December 27th. COROT is a mission of astronomy led by CNES, in association with CNRS, aimed to detect extra-solar planets. The third Proteus 5PF mission, the oceanography satellite Jason2, has been successfully launched on 2008 June 20th. JASON2 is a fourth-partner mission with NASA, CNES, EUMETSAT and NOAA, whose objective is to continue JASON1 sea surface topography measurements with a goal of improving accuracy to 2.5 centimeters. The fourth Proteus 5PF mission, the scientific earth observation satellite SMOS, has been launched on 2009

  8. Functional electrical stimulation on paraplegic patients

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    Helmut Kern

    2014-07-01

    Full Text Available We report on clinical and physiological effects of 8 months Functional Electrical Stimulation (FES of quadriceps femoris muscle on 16 paraplegic patients. Each patient had muscle biopsies, CT-muscle diameter measurements, knee extension strength testing carried out before and after 8 months FES training. Skin perfusion was documented through infrared telethermography and xenon clearance, muscle perfusion was recorded through thallium scintigraphy. After 8 months FES training baseline skin perfusion showed 86 % increase, muscle perfusion was augmented by 87 %. Muscle fiber diameters showed an average increase of 59 % after 8 months FES training. Muscles in patients with spastic paresis as well as in patients with denervation showed an increase in aerob and anaerob muscle enzymes up to the normal range. Even without axonal neurotropic substances FES was able to demonstrate fiberhypertrophy, enzyme adaptation and intracellular structural benefits in denervated muscles. The increment in muscle area as visible on CT-scans of quadriceps femoris was 30 % in spastic paraplegia and 10 % in denervated patients respectively. FES induced changes were less in areas not directly underneath the surface electrodes. We strongly recommend the use of Kern`s current for FES in denervated muscles to induce tetanic muscle contractions as we formed a very critical opinion of conventional exponential current. In patients with conus-cauda-lesions FES must be integrated into modern rehabilitation to prevent extreme muscle degeneration and decubital ulcers. Using FES we are able to improve metabolism and induce positive trophic changes in our patients lower extremities. In spastic paraplegics the functions „rising and walking“ achieved through FES are much better training than FES ergometers. Larger muscle masses are activated and an increased heart rate is measured, therefore the impact on cardiovascular fitness and metabolism is much greater. This effectively

  9. Plasmonic functionalities based on detuned electrical dipoles

    DEFF Research Database (Denmark)

    Pors, Anders Lambertus; Nielsen, Michael Grøndahl; Bozhevolnyi, Sergey I.

    2013-01-01

    We introduce and demonstrate the concept of detuned electrical dipoles (DED) that originates from the plasmonic realization of the dressed-state picture of electromagnetically induced transparency in atomic physics. Numerically and experimentally analyzing DED metamaterials consisting of unit cells...

  10. Electromyographic evaluation of functional electrical stimulation to injured oculomotor nerve

    Institute of Scientific and Technical Information of China (English)

    Min Yang; Shiting Li; Youqiang Meng; Ningxi Zhu; Xuhui Wang; Liang Wan; Wenchuan Zhang; Jun Zhong; Shugan Zhu; Massimiliano Visocchi

    2011-01-01

    Functional electrical stimulation delivered early after injury to the proximal nerve stump has been proposed as a therapeutic approach for enhancing the speed and specificity of axonal regeneration following nerve injury. In this study, the injured oculomotor nerve was stimulated functionally by an implantable electrode. Electromyographic monitoring of the motor unit potential of the inferior oblique muscle was conducted for 12 weeks in two injury groups, one with and one without electric stimulation. The results revealed that, at 2, 4, 6, 8 weeks after functional electric stimulation of the injured oculomotor nerve, motor unit potentials significantly increased, such that amplitude was longer and spike duration gradually shortened. These findings indicate that the injured oculomotor nerve has the potential for regeneration and repair, but this ability is not sufficient for full functional recovery to occur. Importantly, the current results indicated that recovery and regeneration of the injured oculomotor nerve can be promoted with functional electrical stimulation.

  11. Review of real brain-controlled wheelchairs

    Science.gov (United States)

    Fernández-Rodríguez, Á.; Velasco-Álvarez, F.; Ron-Angevin, R.

    2016-12-01

    This paper presents a review of the state of the art regarding wheelchairs driven by a brain-computer interface. Using a brain-controlled wheelchair (BCW), disabled users could handle a wheelchair through their brain activity, granting autonomy to move through an experimental environment. A classification is established, based on the characteristics of the BCW, such as the type of electroencephalographic signal used, the navigation system employed by the wheelchair, the task for the participants, or the metrics used to evaluate the performance. Furthermore, these factors are compared according to the type of signal used, in order to clarify the differences among them. Finally, the trend of current research in this field is discussed, as well as the challenges that should be solved in the future.

  12. Functional electrical stimulation bicycle ergometry: patient perceptions.

    Science.gov (United States)

    Sipski, M L; Delisa, J A; Schweer, S

    1989-06-01

    Forty-seven patients who had participated in a clinical electrical stimulation ergometry program were administered a questionnaire to determine their perceptions of the therapy. Improved endurance was reported by 62% of paraplegics and 65% of quadriplegics. Sixty-two percent of paraplegics and 56% of quadriplegics reported improved self-image, while 54% of paraplegics and 77% of quadriplegics perceived their appearance was better. Thirty-nine percent of paraplegics and 24% of quadriplegics noted decreased lower extremity edema with training. Six out of nine patients with a previous history of neurogenic pain noted an increase in pain, which caused them to leave the program.

  13. Optimizing electricity consumption: A case of function learning.

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    Guath, Mona; Millroth, Philip; Juslin, Peter; Elwin, Ebba

    2015-12-01

    A popular way to improve consumers' control over their electricity consumption is by providing outcome feedback on the cost with in-home displays. Research on function learning, however, suggests that outcome feedback may not always be ideal for learning, especially if the feedback signal is noisy. In this study, we relate research on function learning to in-home displays and use a laboratory task simulating a household to investigate the role of outcome feedback and function learning on electricity optimization. Three function training schemes (FTSs) are presented that convey specific properties of the functions that relate the electricity consumption to the utility and cost. In Experiment 1, we compared learning from outcome feedback with 3 FTSs, 1 of which allowed maximization of the utility while keeping the budget, despite no feedback about the total monthly cost. In Experiment 2, we explored the combination of this FTS and outcome feedback. The results suggested that electricity optimization may be facilitated if feedback learning is preceded by a brief period of function training.

  14. Brain-controlled body movement assistance devices and methods

    Energy Technology Data Exchange (ETDEWEB)

    Leuthardt, Eric C.; Love, Lonnie J.; Coker, Rob; Moran, Daniel W.

    2017-01-10

    Methods, devices, systems, and apparatus, including computer programs encoded on a computer storage medium, for brain-controlled body movement assistance devices. In one aspect, a device includes a brain-controlled body movement assistance device with a brain-computer interface (BCI) component adapted to be mounted to a user, a body movement assistance component operably connected to the BCI component and adapted to be worn by the user, and a feedback mechanism provided in connection with at least one of the BCI component and the body movement assistance component, the feedback mechanism being configured to output information relating to a usage session of the brain-controlled body movement assistance device.

  15. A distributed transducer system for functional electrical stimulation

    DEFF Research Database (Denmark)

    Gudnason, Gunnar; Nielsen, Jannik Hammel; Bruun, Erik

    2001-01-01

    Implanted transducers for functional electrical stimulation (FES) powered by inductive links are subject to conflicting requirements arising from low link efficiency, a low power budget and the need for protection of the weak signals against strong RF electromagnetic fields. We propose a solution...

  16. Modulation of proprioceptive feedback during functional electrical stimulation

    DEFF Research Database (Denmark)

    Christensen, Mark Schram; Grey, Michael James

    2013-01-01

    Functional electrical stimulation (FES) is sometimes used as a therapeutic modality in motor rehabilitation to augment voluntary motor drive to effect movement that would otherwise not be possible through voluntary activation alone. Effective motor rehabilitation should require that the central n...

  17. Functionally Graded Interfaces: Role and Origin of Internal Electric Field and Modulated Electrical Response.

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    Maurya, Deepam; Zhou, Yuan; Chen, Bo; Kang, Min-Gyu; Nguyen, Peter; Hudait, Mantu K; Priya, Shashank

    2015-10-14

    We report the tunable electrical response in functionally graded interfaces in lead-free ferroelectric thin films. Multilayer thin film graded heterostructures were synthesized on platinized silicon substrate with oxide layers of varying thickness. Interestingly, the graded heterostructure thin films exhibited shift of the hysteresis loops on electric field and polarization axes depending upon the direction of an applied bias. A diode-like characteristics was observed in current-voltage behavior under forward and reverse bias. This modulated electrical behavior was attributed to the perturbed dynamics of charge carriers under internal bias (self-bias) generated due to the increased skewness of the potential wells. The cyclic sweeping of voltage further demonstrated memristor-like current-voltage behavior in functionally graded heterostructure devices. The presence of an internal bias assisted the generation of photocurrent by facilitating the separation of photogenerated charges. These novel findings provide opportunity to design new circuit components for the next generation of microelectronic device architectures.

  18. Alteration in sensory nerve function following electrical shock.

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    Abramov, G S; Bier, M; Capelli-Schellpfeffer, M; Lee, R C

    1996-12-01

    A study of the effects of electrical shock on peripheral nerve fibres is presented. Strength and duration of the applied shocks were similar to those encountered in a typical industrial electrical accident. The purpose of this study is: (i) to identify the electrophysiological and morphological change in nerve fibres after the application of electrical current shocks; (ii) to examine the ability of the peripheral nerve fibres to spontaneously regain function and; (iii) to demonstrate the usefulness of the sensory refractory spectrum as an additional technique in assessing the damage. Three groups of animals received twelve 4-ms electric field pulses of approximately 37 V/cm (n = 5), 75 V/cm (n = 9) and 150 V/cm (n = 6), respectively. Group 4 was a control group and received a direct application of 2 per cent lidocaine over the sciatic nerve for 30 min. Thermal effects of the shocks were negligible. The sensory refractory spectrum shows that electrical shock damage was mainly to the large, fast myelinated fibres and that higher field strengths do more damage. Also in a histological examination it was found that the more heavily shocked myelinated fibres had sustained more damage.

  19. Effects of functional electrical stimulation in rehabilitation with hemiparesis patients.

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    Tanovic, Edina

    2009-02-01

    Cerebrovascular accident is a focal neurological deficiency occurring suddenly and lasting for more than 24 hours. The purpose of our work is to determine the role of the functional electrical simulation (FES) in the rehabilitation of patients with hemiparesis, which occurred as a consequence of a cerebrovascular accident. This study includes the analysis of two groups of 40 patients with hemiparesis (20 patients with deep hemiparesis and 20 patients with light hemiparesis), a control group which was only treated with kinesiotherapy and a tested group which was treated with kinesiotherapy and functional electrical stimulation. Both groups of patients were analyzed in respect to their sex and age. Additional analysis of the walking function was completed in accordance with the BI and RAP index. The analysis of the basic demographical data demonstrated that there is no significant difference between the control and tested group. The patients of both groups are equal in respect of age and sex. After 4 weeks of rehabilitation of patients with deep and light hemiparesis there were no statistically significant differences between the groups after evaluation by the BI index. However, a statistically significant difference was noted between the groups by the RAP index among patients with deep hemiparesis. After 8 weeks of rehabilitation the group of patients who were treated with kinesiotherapy and functional electrical stimulation showed better statistically significant results of rehabilitation in respect to the control group with both the BI index and the RAP index (pstroke is faster and more successful if we used functional electrical stimulation, in combination with kinesiotherapy, in patients with disabled extremities.

  20. Molecular electric moments calculated by using natural orbital functional theory

    CERN Document Server

    Mitxelena, Ion

    2016-01-01

    The molecular electric dipole, quadrupole and octupole moments of a selected set of 21 spin-compensated molecules are determined employing the extended version of the Piris natural orbital functional 6 (PNOF6), using the triple-$\\zeta$ Gaussian basis set with polarization functions developed by Sadlej, at the experimental geometries. The performance of the PNOF6 is established by carrying out a statistical analysis of the mean absolute errors with respect to the experiment. The calculated PNOF6 electric moments agree satisfactorily with the corresponding experimental data, and are in good agreement with the values obtained by accurate ab initio methods, namely, the coupled-cluster single and doubles (CCSD) and multi-reference single and double excitation configuration interaction (MRSD-CI) methods.

  1. Brain-Computer Interface Controlled Functional Electrical Stimulation System for Ankle Movement

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    King Christine E

    2011-08-01

    Full Text Available Abstract Background Many neurological conditions, such as stroke, spinal cord injury, and traumatic brain injury, can cause chronic gait function impairment due to foot-drop. Current physiotherapy techniques provide only a limited degree of motor function recovery in these individuals, and therefore novel therapies are needed. Brain-computer interface (BCI is a relatively novel technology with a potential to restore, substitute, or augment lost motor behaviors in patients with neurological injuries. Here, we describe the first successful integration of a noninvasive electroencephalogram (EEG-based BCI with a noninvasive functional electrical stimulation (FES system that enables the direct brain control of foot dorsiflexion in able-bodied individuals. Methods A noninvasive EEG-based BCI system was integrated with a noninvasive FES system for foot dorsiflexion. Subjects underwent computer-cued epochs of repetitive foot dorsiflexion and idling while their EEG signals were recorded and stored for offline analysis. The analysis generated a prediction model that allowed EEG data to be analyzed and classified in real time during online BCI operation. The real-time online performance of the integrated BCI-FES system was tested in a group of five able-bodied subjects who used repetitive foot dorsiflexion to elicit BCI-FES mediated dorsiflexion of the contralateral foot. Results Five able-bodied subjects performed 10 alternations of idling and repetitive foot dorsifiexion to trigger BCI-FES mediated dorsifiexion of the contralateral foot. The epochs of BCI-FES mediated foot dorsifiexion were highly correlated with the epochs of voluntary foot dorsifiexion (correlation coefficient ranged between 0.59 and 0.77 with latencies ranging from 1.4 sec to 3.1 sec. In addition, all subjects achieved a 100% BCI-FES response (no omissions, and one subject had a single false alarm. Conclusions This study suggests that the integration of a noninvasive BCI with a lower

  2. BCI-Triggered functional electrical stimulation therapy for upper limb

    Directory of Open Access Journals (Sweden)

    Cesar Marquez-Chin

    2016-08-01

    Full Text Available We present here the integration of brain-computer interfacing (BCI technology with functional electrical stimulation therapy to restore voluntary function. The system was tested with a single man with chronic (6 years severe left hemiplegia resulting from a stroke. The BCI, implemented as a simple “brain-switch” activated by power decreases in the 18 Hz – 28 Hz frequency range of the participant’s electroencephalograpic signals, triggered a neuroprosthesis designed to facilitate forward reaching, reaching to the mouth, and lateral reaching movements. After 40 90-minute sessions in which the participant attempted the reaching tasks repeatedly, with the movements assisted by the BCI-triggered neuroprosthesis, the participant’s arm function showed a clinically significant six point increase in the Fugl-Meyer Asessment Upper Extermity Sub-Score. These initial results suggest that the combined use of BCI and functional electrical stimulation therapy may restore voluntary reaching function in individuals with chronic severe hemiplegia for whom the rehabilitation alternatives are very limited.

  3. Effects of functional electrical therapy on upper extremity functional motor recovery in patients after stroke: Our experience and future directions

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    Plavšić Aleksandra

    2011-01-01

    Full Text Available Introduction. New neurorehabilitation together with conventional techniques provide methods and technologies for maximizing what is preserved from the sensory motor system after cerebrovascular insult. The rehabilitation technique named functional electrical therapy was investigated in more than 60 patients in acute, subacute and chronic phase after cerebrovascular insult. The functional sensory information generated by functional electrical therapy was hypothesized to result in the intensive functional brain training of the activities performed. Functional Electrical Therapy. Functional electrical therapy is a combination of functional exercise and electrical therapy. The functional electrical therapy protocol comprises voluntary movement of the paretic arm in synchrony with the electrically assisted hand functions in order to perform typical daily activities. The daily treatment of 30 minutes lasts three weeks. The outcome measures include several tests for the evaluation of arm/hand functionality: upper extremity function test, drawing test, modified Aschworth scale, motor activity log and passive range of movement. Results of Functional Electrical Therapy Studies. Results from our several clinical studies showed that functional electrical therapy, if applied in acute and subacute stroke patients, leads to faster and greater improvement of functioning of the hemiplegic arm/hand compared to the control group. The outcomes were significantly superior at all times after the treatment for the higher functioning group. Discussion. Additional well-planned clinical studies are needed to determine the adequate dose of treatment (timing, duration, intensity with functional electrical therapy regarding the patient’s status. A combination with other techniques should be further investigated.

  4. Rebuilding motor function of the spinal cord based on functional electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    Xiao-yan Shen; Wei Du; Wei Huang; Yi Chen

    2016-01-01

    Rebuilding the damaged motor function caused by spinal cord injury is one of the most serious challenges in clinical neuroscience. The function of the neural pathway under the damaged sites can be rebuilt using functional electrical stimulation technology. In this study, the locations of motor function sites in the lumbosacral spinal cord were determined with functional electrical stimulation technology. A three-dimensional map of the lumbosacral spinal cord comprising the relationship between the motor function sites and the correspond-ing muscle was drawn. Based on the individual experimental parameters and normalized coordinates of the motor function sites, the motor function sites that control a certain muscle were calculated. Phasing pulse sequences were delivered to the determined motor function sites in the spinal cord and hip extension, hip lfexion, ankle plantarlfexion, and ankle dorsilfexion movements were successfully achieved. The results show that the map of the spinal cord motor function sites was valid. This map can provide guidance for the selection of electrical stimulation sites during the rebuilding of motor function after spinal cord injury.

  5. Green's functions in an external electric field

    Energy Technology Data Exchange (ETDEWEB)

    Gavrilov, S.P.; Gitman, D.M.; Shvartsman, S.M.

    1979-04-01

    An approach to quantum electrodynamics in an intense electromagnetic field was proposed in Ref. 1 (E. S. Fradkin and D. M. Gitman, Preprint, MIT, 1978). In the case when the vacuum is unstable with respect to electron-positron pair production, an entire series of various Green's functions in an external classical field enters into the theory. In the present study these Green's functions are calculated for the case of a constant homogeneous electric field. The results are presented in the form of contour integrals over the proper time. The operator representations of the Green's functions in this field are given. Only scalar QED is considered.

  6. Safety measures implemented for modular functioning electrical stimulators.

    Science.gov (United States)

    Chen, Chiun-Fan; Lai, Jin-Shin; Chen, Shih-Wei; Lin, Yin-Tsong; Kuo, Te-Son

    2009-01-01

    The modular architecture allows for greater flexibility in the building of neural prostheses with a variety of channels but may result in unpredictable accidents under circumstances such as sensor displacements, improper coordination of the connected modules and malfunction of any individual module. A novel fail-safe interface is offered as a solution that puts in place the necessary safety measures when building a module based functional electrical stimulator. By using a single reference line in the interconnecting bus of the modules, various commands would immediately be directed to each module so that proper actions may be taken.

  7. Combining functional magnetic resonance imaging with transcranial electrical stimulation

    Directory of Open Access Journals (Sweden)

    Catarina eSaiote

    2013-08-01

    Full Text Available Transcranial electrical stimulation (tES is a neuromodulatory method with promising potential for basic research and as a therapeutic tool. The most explored type of tES is transcranial direct current stimulation (tDCS, but also transcranial alternating current stimulation (tACS and transcranial random noise stimulation (tRNS have been shown to affect cortical excitability, behavioral performance and brain activity. Although providing indirect measure of brain activity, functional magnetic resonance imaging (fMRI can tell us more about the global effects of stimulation in the whole brain and what is more, on how it modulates functional interactions between brain regions, complementing what is known from electrophysiological methods such as measurement of motor evoked potentials. With this review, we aim to present the studies that have combined these techniques, the current approaches and discuss the results obtained so far.

  8. Magic trait electric organ discharge (EOD): Dual function of electric signals promotes speciation in African weakly electric fish

    OpenAIRE

    Feulner, Philine GD; Plath, Martin; Engelmann, Jacob; Kirschbaum, Frank; Tiedemann, Ralph

    2009-01-01

    A unique evolutionary specialization of African weakly electric fish (Mormyridae) is their ability to produce and perceive electric signals. Mormyrids use their electric organs discharge (EOD) for electrolocation and electrocommunication. Here we discuss the adaptive significance of the EOD in foraging (electric prey detection) in light of recent results demonstrating that mormyrid fish mate assortatively according to EOD waveform characteristics (electric mate choice). Therefore the EOD as a...

  9. Casimir interaction energies for magneto-electric \\delta-function plates

    CERN Document Server

    Milton, Kimball A; Schaden, Martin; Shajesh, K V

    2013-01-01

    We present boundary conditions for the electromagnetic fields on a \\delta-function plate, having both electric and magnetic properties, sandwiched between two magneto-electric semi-infinite half spaces. The optical properties for an isolated \\delta-function plate are shown to be independent of the longitudinal material properties of the plate. The Casimir-Polder energy between an isotropically polarizable atom and a magneto-electric \\delta-function plate is attractive for a purely electric \\delta-function plate, repulsive for a purely magnetic \\delta-function plate, and vanishes for the simultaneous perfect conductor limit of both electric and magnetic properties of the \\delta-function plate. The interaction energy between two identical \\delta-function plates is always attractive. It can be attractive or repulsive when the plates have electric and magnetic properties interchanged and reproduces Boyer's result for the interaction energy between perfectly conducting electric and magnetic plates. The change in t...

  10. Magic trait electric organ discharge (EOD): Dual function of electric signals promotes speciation in African weakly electric fish.

    Science.gov (United States)

    Feulner, Philine Gd; Plath, Martin; Engelmann, Jacob; Kirschbaum, Frank; Tiedemann, Ralph

    2009-07-01

    A unique evolutionary specialization of African weakly electric fish (Mormyridae) is their ability to produce and perceive electric signals. Mormyrids use their electric organs discharge (EOD) for electrolocation and electrocommunication. Here we discuss the adaptive significance of the EOD in foraging (electric prey detection) in light of recent results demonstrating that mormyrid fish mate assortatively according to EOD waveform characteristics (electric mate choice). Therefore the EOD as a single trait pleiotropically combines natural divergent selection and reproductive isolation. Consequently we postulate the EOD as a "magic trait" promoting the diversification of African weakly electric fish.

  11. Lung Ventilation Functional Monitoring Based on Electrical Impedance Tomography

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiaoyan; WANG Huaxiang; ZHAO Bo; SHI Xiaolei

    2009-01-01

    Medically,electrical impedance tomography(EIT)is a relatively inexpensive,safe,non-invasive and portable technique compared with computerized tomography(CT)and magnetic resonance imaging(MRI).In this paper,EIT_TJU_Ⅱ system is developed including both the data collection system and image reconstruction algorithm.The testing approach of the system performance,including spatial resolution and sensitivity,is described through brine tank experiments.The images of the thorax physical model verify that the system can reconstruct the interior resistivity distribution.Finally,the lung ventilation functional monitoring in vivo is realized by EIT,and the visualized images indicate that the configuration and performance of EIT_TJU_Ⅱ system are feasible and EIT is a promising technique in clinical monitoring application.

  12. Electrical stimulation for testing neuromuscular function: from sport to pathology.

    Science.gov (United States)

    Millet, Guillaume Y; Martin, Vincent; Martin, Alain; Vergès, Samuel

    2011-10-01

    The use of electrical stimulation (ES) can contribute to our knowledge of how our neuromuscular system can adapt to physical stress or unloading. Although it has been recently challenged, the standard technique used to explore central modifications is the twitch interpolated method which consists in superimposing single twitches or high-frequency doublets on a maximal voluntary contraction (MVC) and to compare the superimposed response to the potentiated response obtained from the relaxed muscle. Alternative methods consist in (1) superimposing a train of stimuli (central activation ratio), (2) comparing the MVC response to the force evoked by a high-frequency tetanus or (3) examining the change in maximal EMG response during voluntary contractions, if this variable is normalized to the maximal M wave, i.e. EMG response to a single stimulus. ES is less used to examine supraspinal factors but it is useful for investigating changes at the spinal level, either by using H reflexes, F waves or cervicomedullary motor-evoked potentials. Peripheral changes can be examined with ES, usually by stimulating the muscle in the relaxed state. Neuromuscular propagation of action potentials on the sarcolemma (M wave, high-frequency fatigue), excitation-contraction coupling (e.g. low-frequency fatigue) and intrinsic force (high-frequency stimulation at supramaximal intensity) can all be used to non-invasively explore muscular function with ES. As for all indirect methods, there are limitations and these are discussed in this review. Finally, (1) ES as a method to measure respiratory muscle function and (2) the comparison between electrical and magnetic stimulation will also be considered.

  13. Experimental Economics for Teaching the Functioning of Electricity Markets

    Science.gov (United States)

    Guevara-Cedeno, J. Y.; Palma-Behnke, R.; Uribe, R.

    2012-01-01

    In the field of electricity markets, the development of training tools for engineers has been extremely useful. A novel experimental economics approach based on a computational Web platform of an electricity market is proposed here for the practical teaching of electrical engineering students. The approach is designed to diminish the gap that…

  14. Interaction of poststroke voluntary effort and functional neuromuscular electrical stimulation.

    Science.gov (United States)

    Makowski, Nathaniel; Knutson, Jayme; Chae, John; Crago, Patrick

    2013-01-01

    Functional electrical stimulation (FES) may be able to augment functional arm and hand movement after stroke. Poststroke neuroprostheses that incorporate voluntary effort and FES to produce the desired movement must consider how forces generated by voluntary effort and FES combine, even in the same muscle, in order to provide an appropriate level of stimulation to elicit the desired assistive force. The goal of this study was to determine whether the force produced by voluntary effort and FES add together independently of effort or whether the increment in force depends on the level of voluntary effort. Isometric force matching tasks were performed under different combinations of voluntary effort and FES. Participants reached a steady level of force, and while attempting to maintain a constant effort level, FES was applied to augment the force. Results indicate that the increment in force produced by FES decreases as the level of initial voluntary effort increases. Potential mechanisms causing the change in force output are proposed, but the relative contribution of each mechanism is unknown.

  15. Radial Basis Function Neural Network-based PID model for functional electrical stimulation system control.

    Science.gov (United States)

    Cheng, Longlong; Zhang, Guangju; Wan, Baikun; Hao, Linlin; Qi, Hongzhi; Ming, Dong

    2009-01-01

    Functional electrical stimulation (FES) has been widely used in the area of neural engineering. It utilizes electrical current to activate nerves innervating extremities affected by paralysis. An effective combination of a traditional PID controller and a neural network, being capable of nonlinear expression and adaptive learning property, supply a more reliable approach to construct FES controller that help the paraplegia complete the action they want. A FES system tuned by Radial Basis Function (RBF) Neural Network-based Proportional-Integral-Derivative (PID) model was designed to control the knee joint according to the desired trajectory through stimulation of lower limbs muscles in this paper. Experiment result shows that the FES system with RBF Neural Network-based PID model get a better performance when tracking the preset trajectory of knee angle comparing with the system adjusted by Ziegler- Nichols tuning PID model.

  16. Electrical activity patterns and the functional maturation of the neocortex.

    Science.gov (United States)

    Kilb, Werner; Kirischuk, Sergei; Luhmann, Heiko J

    2011-11-01

    At the earliest developmental stages, sensory neocortical areas in various species reveal distinct patterns of spontaneous neuronal network activity. These activity patterns either propagate over large neocortical areas or synchronize local neuronal ensembles. In vitro and in vivo experiments indicate that these spontaneous activity patterns are generated from neuronal networks in the cerebral cortex, in subcortical structures or in the sensory periphery (retina, cochlea, whiskers). At early stages spontaneous periphery-driven and also sensory evoked activity is relayed to the developing cerebral cortex via the thalamus and the neocortical subplate, which amplifies the afferent sensory input. These early local and large-scale neuronal activity patterns influence a variety of developmental processes during corticogenesis, such as neurogenesis, apoptosis, neuronal migration, differentiation and network formation. The experimental data also indicate that disturbances in early neuronal patterns may have an impact on the development of cortical layers, columns and networks. In this article we review our current knowledge on the origin of early electrical activity patterns in neocortical sensory areas and their functional implications on shaping developing cortical networks.

  17. Searching for Electrical Properties, Phenomena and Mechanisms in the Construction and Function of Chromosomes

    Directory of Open Access Journals (Sweden)

    Ivan Kanev

    2013-03-01

    Full Text Available Our studies reveal previously unidentified electrical properties of chromosomes: (1 chromosomes are amazingly similar in construction and function to electrical transformers; (2 chromosomes possess in their construction and function, components similar to those of electric generators, conductors, condensers, switches, and other components of electrical circuits; (3 chromosomes demonstrate in nano-scale level electromagnetic interactions, resonance, fusion and other phenomena similar to those described by equations in classical physics. These electrical properties and phenomena provide a possible explanation for unclear and poorly understood mechanisms in clinical genetics including: (a electrically based mechanisms responsible for breaks, translocations, fusions, and other chromosomal abnormalities associated with cancer, intellectual disability, infertility, pregnancy loss, Down syndrome, and other genetic disorders; (b electrically based mechanisms involved in crossing over, non-disjunction and other events during meiosis and mitosis; (c mechanisms demonstrating heterochromatin to be electrically active and genetically important.

  18. SPLITTING OF THE SPECTRAL DOMAIN ELECTRICAL DYADIC GREEN'S FUNCTION IN CHIRAL MEDIA

    Institute of Scientific and Technical Information of China (English)

    QIN Zhi-an; QIN Rui; CHEN Yan; SHENG De-yuan

    2005-01-01

    A new method of formulating dyadic Green's functions in lossless , reciprocal and unbounded chiral medium was presented. Based on Helmholtz theorem and the nondivergence and irrotational splitting of dyadic Dirac delta-function was this method, the electrical vector dyadic Green's function equation was first decomposed into the nondivergence electrical vector dyadic Green's function equation and irrotational electrical vector dyadic Green's function equation, and then Fourier's transformation was used to derive the expressions of the non-divergence and irrotational component of the spectral domain electrical dyadic Green's function in chiral media. It can avoid having to use the wavefield decomposition method and dyadic Green's function eigenfunction expansion technique that this method is used to derive the dyadic Green's functions in chiral media.

  19. EFFECT OF TASK SPECIFIC MIRROR THERAPY WITH FUNCTIONAL ELECTRICAL STIMULATION ON UPPER LIMB FUNCTION FOR SUBACUTE HEMIPLEGIA

    Directory of Open Access Journals (Sweden)

    Sumana Nagapattinam

    2015-10-01

    Full Text Available Background: The principal target of any stroke rehabilitation is the motor impairments. Many studies have been advocated on the effect of Functional electrical stimulation and Task specific mirror therapy. Hence, the purpose of the study is to find the combined effect of task specific Mirror therapy with Functional Electrical Stimulation on upper limb function for subjects with sub-acute hemiplegia. Methods: An experimental study design, 60 subjects with sub-acute Hemiplegia randomised into 3 groups, functional electrical stimulation group (n=20, task specific mirror therapy group (n=20, and combined group (n=20. Each group received the corresponding regimen of treatment for 30 minutes with rest period for total 12 sessions over 2 weeks along with conventional physiotherapy. The outcome measure such as action research arm test was measured before and after two weeks of intervention. Result: When means of action research arm test were analyzed within the groups, there was a significant difference within all the three groups. When means were compared between three groups there is no statistically significant difference in pre- intervention and post intervention means. Conclusion: It is concluded that a combination therapy of task specific mirror therapy with functional electrical stimulation for two weeks duration, is shown to be effective for recovery of upper limb function in subjects with sub-acute hemiplegia. However, the combination of task specific mirror therapy and functional electrical stimulation is shown to have similar improvements as only task specific mirror therapy and functional electrical stimulation.

  20. THEORETICAL ASPECTS AND METHODS OF PARAMETERS IDENTIFICATION OF ELECTRIC TRACTION SYSTEM DEVICES. METHOD OF WEIGHT FUNCTION

    Directory of Open Access Journals (Sweden)

    T. N. Mishchenko

    2014-10-01

    Full Text Available Purpose. Development and substantiation of a new method of structural identification of electrical devices of electric traction systems for both DC and AC current. Methodology. To solve this problem the following methods are used: the methods and techniques of the linear electrical engineering, in particular, the Laplace operator method; the numerical method for solving the integral equation, which is based on the representation of the Wiener-Hopf linear equations system (this allows forming the solutions of the problem in a mathematical form of the correlation and weight functions; the factorization method, which provides certain partition of the correlation functions of the stochastic processes. Findings. It was developed the method of weight function of the electrical devices identification, which can be fully used in the systems of electric traction. As the use example of the developed method it was considered a feeder section of DC electric traction with the single power supply. On this section move two electric locomotives of the type DE 1, they have been identified by the weighting functions. The required currents and voltages of electric locomotives are also formulated in the electric traction network in probabilistic and statistical form, that is, the functions of mathematical expectation and the correlation functions are determined. At this, it is taken into account that the correlation function of the sum of random functions is equal to the sum of the correlation functions of additives, and the correlation function of the integral of a random function is defined as the double integral of the correlation function of the output of a random function. Originality. Firstly, originality consists of the adaption of the developed method of structural identification for the devices of electric traction system. Secondly, it lies in the proper development of the new method of weight function. And finally, it lies in the solution of the Wiener

  1. Change of Work Function of Pd, Ag, K on Al(001) as a Function of External Electric Field

    Institute of Scientific and Technical Information of China (English)

    侯柱峰; 黄美纯; 朱梓忠; 黄荣彬; 郑兰荪

    2001-01-01

    We present a local density functional calculation of the effect of an external electric field on the work function change of Pd and Ag adsorption on an Al(001) surface. The adsorption of K has also been considered for comparison. We found that the work functions for all the systems increased linearly when the strength of the external electric field was increased. Since the polarized electrons at the interstitial regions between the adsorbate and substrate for Pd/Al(001) and Ag/Al(001) react to the external electric field differently, the subtle differences between Pd/Al(001) and Ag/Al(001) bondings has been characterized through the comparison of the slopes of the work function change versus electric field.

  2. Simultaneous dynamic electrical and structural measurements of functional materials

    Energy Technology Data Exchange (ETDEWEB)

    Vecchini, C.; Stewart, M.; Muñiz-Piniella, A.; Wooldridge, J. [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom); Thompson, P.; McMitchell, S. R. C.; Bouchenoire, L.; Brown, S.; Wermeille, D.; Lucas, C. A. [XMaS, The UK-CRG, ESRF-The European Synchrotron, CS40220, F-38043, Grenoble Cedex 09 (France); Department of Physics, University of Liverpool, Liverpool L69 3BX (United Kingdom); Lepadatu, S. [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom); Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Bikondoa, O.; Hase, T. P. A. [XMaS, The UK-CRG, ESRF-The European Synchrotron, CS40220, F-38043, Grenoble Cedex 09 (France); Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Lesourd, M. [ESRF-The European Synchrotron, CS40220, F-38043, Grenoble Cedex 09 (France); Dontsov, D. [SIOS Meßtechnik GmbH, Am Vogelherd 46, 98693 Ilmenau (Germany); Cain, M. G. [National Physical Laboratory, Hampton Road, Teddington TW11 0LW (United Kingdom); Electrosciences Ltd., Farnham, Surrey GU9 9QT (United Kingdom)

    2015-10-15

    A new materials characterization system developed at the XMaS beamline, located at the European Synchrotron Radiation Facility in France, is presented. We show that this new capability allows to measure the atomic structural evolution (crystallography) of piezoelectric materials whilst simultaneously measuring the overall strain characteristics and electrical response to dynamically (ac) applied external stimuli.

  3. Brain-controlled telepresence robot by motor-disabled people.

    Science.gov (United States)

    Tonin, Luca; Carlson, Tom; Leeb, Robert; del R Millán, José

    2011-01-01

    In this paper we present the first results of users with disabilities in mentally controlling a telepresence robot, a rather complex task as the robot is continuously moving and the user must control it for a long period of time (over 6 minutes) to go along the whole path. These two users drove the telepresence robot from their clinic more than 100 km away. Remarkably, although the patients had never visited the location where the telepresence robot was operating, they achieve similar performances to a group of four healthy users who were familiar with the environment. In particular, the experimental results reported in this paper demonstrate the benefits of shared control for brain-controlled telepresence robots. It allows all subjects (including novel BMI subjects as our users with disabilities) to complete a complex task in similar time and with similar number of commands to those required by manual control.

  4. Effects of a multichannel dynamic functional electrical stimulation system on hemiplegic gait and muscle forces.

    Science.gov (United States)

    Qian, Jing-Guang; Rong, Ke; Qian, Zhenyun; Wen, Chen; Zhang, Songning

    2015-11-01

    [Purpose] The purpose of the study was to design and implement a multichannel dynamic functional electrical stimulation system and investigate acute effects of functional electrical stimulation of the tibialis anterior and rectus femoris on ankle and knee sagittal-plane kinematics and related muscle forces of hemiplegic gait. [Subjects and Methods] A multichannel dynamic electrical stimulation system was developed with 8-channel low frequency current generators. Eight male hemiplegic patients were trained for 4 weeks with electric stimulation of the tibia anterior and rectus femoris muscles during walking, which was coupled with active contraction. Kinematic data were collected, and muscle forces of the tibialis anterior and rectus femoris of the affected limbs were analyzed using a musculoskelatal modeling approach before and after training. A paired sample t-test was used to detect the differences between before and after training. [Results] The step length of the affected limb significantly increased after the stimulation was applied. The maximum dorsiflexion angle and maximum knee flexion angle of the affected limb were both increased significantly during stimulation. The maximum muscle forces of both the tibia anterior and rectus femoris increased significantly during stimulation compared with before functional electrical stimulation was applied. [Conclusion] This study established a functional electrical stimulation strategy based on hemiplegic gait analysis and musculoskeletal modeling. The multichannel functional electrical stimulation system successfully corrected foot drop and altered circumduction hemiplegic gait pattern.

  5. Calculate Electric Field Gradient of TiO2 Within Density Functional Theory

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>TiO2 electric field gradient has been calculated utilizing WIEN2K program, which is ab initio based on density function theory (DFT). DFT uses the charge density as a variable instead of electronic wave

  6. Efficient and accurate computation of electric field dyadic Green's function in layered media

    CERN Document Server

    Cho, Min Hyung

    2016-01-01

    Concise and explicit formulas for dyadic Green's functions, representing the electric and magnetic fields due to a dipole source placed in layered media, are derived in this paper. First, the electric and magnetic fields in the spectral domain for the half space are expressed using Fresnel reflection and transmission coefficients. Each component of electric field in the spectral domain constitutes the spectral Green's function in layered media. The Green's function in the spatial domain is then recovered involving Sommerfeld integrals for each component in the spectral domain. By using Bessel identities, the number of Sommerfeld integrals are reduced, resulting in much simpler and more efficient formulas for numerical implementation compared with previous results. This approach is extended to the three-layer Green's function. In addition, the singular part of the Green's function is naturally separated out so that integral equation methods developed for free space Green's functions can be used with minimal mo...

  7. A novel functional electrical stimulation-control system for restoring motor function of post-stroke hemiplegic patients

    Institute of Scientific and Technical Information of China (English)

    Zonghao Huang; Zhigong Wang; Xiaoying Lv; Yuxuan Zhou; Haipeng Wang; Sihao Zong

    2014-01-01

    Hemiparesis is one of the most common consequences of stroke. Advanced rehabilitation tech-niques are essential for restoring motor function in hemiplegic patients. Functional electrical stimulation applied to the affected limb based on myoelectric signal from the unaffected limb is a promising therapy for hemiplegia. In this study, we developed a prototype system for evaluating this novel functional electrical stimulation-control strategy. Based on surface electromyography and a vector machine model, a self-administered, multi-movement, force-modulation functional electrical stimulation-prototype system for hemiplegia was implemented. This paper discusses the hardware design, the algorithm of the system, and key points of the self-oscillation-prone system. The experimental results demonstrate the feasibility of the prototype system for further clinical trials, which is being conducted to evaluate the efifcacy of the proposed rehabilitation technique.

  8. Nanowires and Electrical Stimulation Synergistically Improve Functions of hiPSC Cardiac Spheroids.

    Science.gov (United States)

    Richards, Dylan J; Tan, Yu; Coyle, Robert; Li, Yang; Xu, Ruoyu; Yeung, Nelson; Parker, Arran; Menick, Donald R; Tian, Bozhi; Mei, Ying

    2016-07-13

    The advancement of human induced pluripotent stem-cell-derived cardiomyocyte (hiPSC-CM) technology has shown promising potential to provide a patient-specific, regenerative cell therapy strategy to treat cardiovascular disease. Despite the progress, the unspecific, underdeveloped phenotype of hiPSC-CMs has shown arrhythmogenic risk and limited functional improvements after transplantation. To address this, tissue engineering strategies have utilized both exogenous and endogenous stimuli to accelerate the development of hiPSC-CMs. Exogenous electrical stimulation provides a biomimetic pacemaker-like stimuli that has been shown to advance the electrical properties of tissue engineered cardiac constructs. Recently, we demonstrated that the incorporation of electrically conductive silicon nanowires to hiPSC cardiac spheroids led to advanced structural and functional development of hiPSC-CMs by improving the endogenous electrical microenvironment. Here, we reasoned that the enhanced endogenous electrical microenvironment of nanowired hiPSC cardiac spheroids would synergize with exogenous electrical stimulation to further advance the functional development of nanowired hiPSC cardiac spheroids. For the first time, we report that the combination of nanowires and electrical stimulation enhanced cell-cell junction formation, improved development of contractile machinery, and led to a significant decrease in the spontaneous beat rate of hiPSC cardiac spheroids. The advancements made here address critical challenges for the use of hiPSC-CMs in cardiac developmental and translational research and provide an advanced cell delivery vehicle for the next generation of cardiac repair.

  9. Subharmonic functions and electric fields in ball layers. II

    Directory of Open Access Journals (Sweden)

    O. P. Gnatiuk

    2011-03-01

    Full Text Available In this sequel to cite{GK} we study a special case $BL(frac{1}{r},r$, $r>1$. Alsothe explicit representation of a subharmonic extension for a subharmonic function $u(x$ near a removable point is obtained. Moreover, the diverse Nevanlinna characteristics are compared.

  10. Functionalized perylenes: origin of the enhanced electrical performances

    NARCIS (Netherlands)

    Piliego, C.; Cordella, F.; Jarzab, D.; Lu, S.; Chen, Z.; Facchetti, A.; Loi, M.A.

    2009-01-01

    {In this letter we compare the transistor performances of two solution-processed perylene derivatives: N,N'-bis (n-octyl)- dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDI8-CN2) and N,N'-1H,1H-perfluorobutyl dicyanoperylenediimide (PDIF-CN2). Perylenediimide nitrogen functionalization with perfluoro

  11. Electrically tunable functional nanomaterials for actuation and photonics

    OpenAIRE

    Shao, Li-Hua

    2012-01-01

    Nanomaterials with tunable electronic structure exploit the large specific surface area of metal nanostructures along with the strategy of tuning the surface properties through the controlled introduction of space-charge regions. Then, materials with tunable macroscopic properties can be created. The present thesis work achieved a successful synthesis of metallic and carbon-based tunable nanomaterials and demonstrated novel functional behavior in two fields of application: actuation and photo...

  12. 50-60 Hz electric and magnetic field effects on cognitive function in humans: A review

    Energy Technology Data Exchange (ETDEWEB)

    Crasson, M

    2003-07-01

    This paper reviews the effect of 50-60 Hz weak electric, magnetic and combined electric and magnetic field exposure on cognitive functions such as memory, attention, information processing and time perception, as determined by electroencephalographic methods and performance measures. Overall, laboratory studies, which have investigated the acute effects of power frequency fields on cognitive functioning in humans are heterogeneous, in terms of both electric and magnetic field (EMF) exposure and the experimental design and measures used. Results are inconsistent and difficult to interpret with regard to functional relevance for possible health risks. Statistically significant differences between field and control exposure, when they are found, are small, subtle, transitory, without any clear dose-response relationship and difficult to reproduce. The human performance or event related potentials (ERPs) measures that might specifically be affected by EMF exposure, as well as a possible cerebral structure or function that could be more sensitive to EMF, cannot be better determined. (author)

  13. Functional electrical stimulation-assisted walking for persons with incomplete spinal injuries

    DEFF Research Database (Denmark)

    Ladouceur, M.; Barbeau, H.

    2000-01-01

    This study investigated the changes in maximal overground walking speed (MOWS) that occurred during; walking training with a functional electrical stimulation (FES) orthosis by chronic spinal cord injured persons with incomplete motor function loss. The average walking: speed over a distance of 10...

  14. Muscle twitch responses for shaping the multi-pad electrode for functional electrical stimulation

    OpenAIRE

    Malešević Nebojša; Popović Lana; Bijelić Goran; Kvaščev Goran

    2010-01-01

    In this paper we present a method for optimization of multi-pad electrode spatial selectivity during transcutaneous Functional Electrical Stimulation (FES) of hand. The presented method is based on measurement of individual muscle twitch responses during low frequency electrical stimulation via pads within multi-pad electrode. Twitch responses are recorded by Micro-Electro-Mechanical Systems (MEMS) accelerometers. The aim of this methodology is to substitute bulky sensors, torque sensor...

  15. The supply function equilibrium and its policy implications for wholesale electricity auctions

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, Paer [Research Institute of Industrial Economics (IFN), Box 55665, Grevgatan 34, 10215 Stockholm (Sweden); Newbery, David [Faculty of Economics, University of Cambridge, Cambridge (United Kingdom)

    2010-12-15

    The supply function equilibrium provides a game-theoretic model of strategic bidding in oligopolistic wholesale electricity auctions. This paper presents an intuitive account of current understanding and shows how welfare losses depend on the number of firms in the market and their asymmetry. Previous results and general recommendations for divisible-good/multi-unit auctions provides guidance on the design of the auction format, setting the reservation price, the rationing rule, and restrictions on the offer curves in wholesale electricity auctions. (author)

  16. Rational function systems and electrical networks with multiparameters

    CERN Document Server

    Lu, KaiSheng

    2012-01-01

    To overcome the problems of system theory and network theory over real field, this book uses matrices over the field F(z) of rational functions in multiparameters describing coefficient matrices of systems and networks and makes systems and network description over F(z) and researches their structural properties: reducible condition of a class of matrices over F(z) and their characteristic polynomial; type1 matrix and two basic properties; variable replacement conditions for independent parameters; structural controllability and observability of linear systems over F(z); separability, reducibi

  17. Simulation of the electrical field in equine larynx to optimize functional electrical stimulation in denervated musculus cricoarythenoideus dorsalis

    Directory of Open Access Journals (Sweden)

    Martin Reichel

    2014-03-01

    Full Text Available Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN in horses can be performed by Functional Electrical Stimulation (FES. Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD and testing electrode configuration until best possible optimum is reached. For better understanding and finding of maximum possible activation of CAD a simulation model of the actual entire setting is currently in development. Therefore the geometric model is built from CT-data of a dissected larynx containing the quadripolar electrodes as well as fiducials for later data registration. The geometric model is the basis for a finite difference method containing of voxels with corresponding electrical conductivity of the different types of tissue due to threshold segmentation of the CT-data. Model validation can be done by the measurement of the 3D electrical potential distribution of a larynx positioned in an electrolytic tray. Finally, measured and calculated results have to be compared as well as further investigated. Preliminary results show, that changes of electrode as well as conductivity configuration leads to significant different voltage distributions and can be well presented by equipotential lines superimposed CT-slices – a Matlab graphical user interface visualizes the results in freely selectable slices of the 3D geometry. Voltage distribution along theoretically estimated fiber paths could be calculated as well as visualized. For further calculation of nerve or denervated muscle fiber activation and its optimization, real fiber paths have to be defined and referenced to the potential- and the CT-data.

  18. Simulation of the electrical field in equine larynx to optimize functional electrical stimulation in denervated musculus cricoarythenoideus dorsalis

    Directory of Open Access Journals (Sweden)

    Martin Reichel

    2014-09-01

    Full Text Available Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN in horses can be performed by Functional Electrical Stimulation (FES. Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD and testing electrode configuration until best possible optimum is reached. For better understanding and finding of maximum possible activation of CAD a simulation model of the actual entire setting is currently in development. Therefore the geometric model is built from CT-data of a dissected larynx containing the quadripolar electrodes as well as fiducials for later data registration. The geometric model is the basis for a finite difference method containing of voxels with corresponding electrical conductivity of the different types of tissue due to threshold segmentation of the CT-data. Model validation can be done by the measurement of the 3D electrical potential distribution of a larynx positioned in an electrolytic tray. Finally, measured and calculated results have to be compared as well as further investigated. Preliminary results show, that changes of electrode as well as conductivity configuration leads to significant different voltage distributions and can be well presented by equipotential lines superimposed CT-slices – a Matlab graphical user interface visualizes the results in freely selectable slices of the 3D geometry. Voltage distribution along theoretically estimated fiber paths could be calculated as well as visualized. For further calculation of nerve or denervated muscle fiber activation and its optimization, real fiber paths have to be defined and referenced to the potential- and the CT-data.

  19. Influence of functionalization on mechanical and electrical properties of carbon nanotube-based silver composites

    Science.gov (United States)

    Pal, Hemant; Sharma, Vimal; Sharma, Manjula

    2014-05-01

    In this study, we have extended the molecular-level mixing method to fabricate multiwall carbon nanotube (CNT)-reinforced silver nanocomposites. The multiwall nanotubes used in the synthesis process were dispersed by two ways viz. covalent and non-covalent functionalization techniques. To elucidate the comparative effects of functionalization, structural, mechanical and electrical properties of nanocomposites were evaluated before and after sintering. The structural characterization revealed that the nanotubes were embedded, anchored and homogenously dispersed within the silver matrix. Hardness and Young's modulus of nanotube-reinforced nanocomposite were increased by a factor of 1-1.6 times than that of pure silver, even before and after the sintering. Covalently functionalized nanotube-based composites have shown more enhanced mechanical properties. The CNT reinforcement also improved the electrical conductivity of low-conducting nanosilver matrix before sintering. Non-covalently functionalized nanotube-based nanosilver composites showed more increased electrical conductivity before sintering. But a negative reinforcement effect was observed in high-conducting bulk silver matrix after the sintering. Thus, covalent functionalization might be appropriate for mechanical improvement in low-strength materials. However, non-covalent functionalization is suitable for electrical enhancement in low-conducting nanomaterials.

  20. Electric Field Encephalography as a tool for functional brain research: a modeling study.

    Directory of Open Access Journals (Sweden)

    Yury Petrov

    Full Text Available We introduce the notion of Electric Field Encephalography (EFEG based on measuring electric fields of the brain and demonstrate, using computer modeling, that given the appropriate electric field sensors this technique may have significant advantages over the current EEG technique. Unlike EEG, EFEG can be used to measure brain activity in a contactless and reference-free manner at significant distances from the head surface. Principal component analysis using simulated cortical sources demonstrated that electric field sensors positioned 3 cm away from the scalp and characterized by the same signal-to-noise ratio as EEG sensors provided the same number of uncorrelated signals as scalp EEG. When positioned on the scalp, EFEG sensors provided 2-3 times more uncorrelated signals. This significant increase in the number of uncorrelated signals can be used for more accurate assessment of brain states for non-invasive brain-computer interfaces and neurofeedback applications. It also may lead to major improvements in source localization precision. Source localization simulations for the spherical and Boundary Element Method (BEM head models demonstrated that the localization errors are reduced two-fold when using electric fields instead of electric potentials. We have identified several techniques that could be adapted for the measurement of the electric field vector required for EFEG and anticipate that this study will stimulate new experimental approaches to utilize this new tool for functional brain research.

  1. Electrical transport of SiNWs array after covalent attachment of new organic functionalities

    Directory of Open Access Journals (Sweden)

    Marianna Ambrico

    2012-05-01

    Full Text Available Modification of the electrical transport of a random network of silicon nanowires assembled on n‐ silicon support, after silicon nanowires functionalization by chlorination/alkylation procedure , is here described and discussed. We show that the organic functionalities induce charge transfer at single SiNW and produce doping‐like effect that is kept in the random network too. The\tSiNWs\tnetwork\talso\tpresents\ta\tsurface recombination velocity lower than that of bulk silicon. Interestingly, the functionalized silicon nanowires/n‐Si junctions display photo‐yield and open circuit voltages higher than those including oxidized silicon nanowire networks. Electrical properties stability in time of junctions embedding propenyl terminated silicon nanowires network and transport modification after secondary functionalization is also shown. These results suggest a possible route for the integration of functionalized\tSi\tnanowires,\talthough\trandomly distributed, in stable large area photovoltaic or molecule sensitive based devices.

  2. Effects of charging and electric field on graphene functionalized with titanium.

    Science.gov (United States)

    Gürel, H Hakan; Ciraci, S

    2013-07-10

    Titanium atoms are adsorbed to graphene with a significant binding energy and render diverse functionalities to it. Carrying out first-principles calculations, we investigated the effects of charging and static electric field on the physical and chemical properties of graphene covered by Ti adatoms. When uniformly Ti covered graphene is charged positively, its antiferromagnetic ground state changes to ferromagnetic metal and attains a permanent magnetic moment. Static electric field applied perpendicularly causes charge transfer between Ti and graphene, and can induce metal-insulator transition. While each Ti adatom adsorbed to graphene atom can hold four hydrogen molecules with a weak binding, these molecules can be released by charging or applying electric field perpendicularly. Hence, it is demonstrated that charging and applied static electric field induce quasi-continuous and side specific modifications in the charge distribution and potential energy of adatoms absorbed to single-layer nanostructures, resulting in fundamentally crucial effects on their physical and chemical properties.

  3. Fish geometry and electric organ discharge determine functional organization of the electrosensory epithelium.

    Directory of Open Access Journals (Sweden)

    Juan Ignacio Sanguinetti-Scheck

    Full Text Available Active electroreception in Gymnotus omarorum is a sensory modality that perceives the changes that nearby objects cause in a self generated electric field. The field is emitted as repetitive stereotyped pulses that stimulate skin electroreceptors. Differently from mormyriformes electric fish, gymnotiformes have an electric organ distributed along a large portion of the body, which fires sequentially. As a consequence shape and amplitude of both, the electric field generated and the image of objects, change during the electric pulse. To study how G. omarorum constructs a perceptual representation, we developed a computational model that allows the determination of the self-generated field and the electric image. We verify and use the model as a tool to explore image formation in diverse experimental circumstances. We show how the electric images of objects change in shape as a function of time and position, relative to the fish's body. We propose a theoretical framework about the organization of the different perceptive tasks made by electroreception: 1 At the head region, where the electrosensory mosaic presents an electric fovea, the field polarizing nearby objects is coherent and collimated. This favors the high resolution sampling of images of small objects and perception of electric color. Besides, the high sensitivity of the fovea allows the detection and tracking of large faraway objects in rostral regions. 2 In the trunk and tail region a multiplicity of sources illuminate different regions of the object, allowing the characterization of the shape and position of a large object. In this region, electroreceptors are of a unique type and capacitive detection should be based in the pattern of the afferents response. 3 Far from the fish, active electroreception is not possible but the collimated field is suitable to be used for electrocommunication and detection of large objects at the sides and caudally.

  4. Application of electrical stimulation for functional tissue engineering in vitro and in vivo

    Science.gov (United States)

    Radisic, Milica (Inventor); Park, Hyoungshin (Inventor); Langer, Robert (Inventor); Freed, Lisa (Inventor); Vunjak-Novakovic, Gordana (Inventor)

    2013-01-01

    The present invention provides new methods for the in vitro preparation of bioartificial tissue equivalents and their enhanced integration after implantation in vivo. These methods include submitting a tissue construct to a biomimetic electrical stimulation during cultivation in vitro to improve its structural and functional properties, and/or in vivo, after implantation of the construct, to enhance its integration with host tissue and increase cell survival and functionality. The inventive methods are particularly useful for the production of bioartificial equivalents and/or the repair and replacement of native tissues that contain electrically excitable cells and are subject to electrical stimulation in vivo, such as, for example, cardiac muscle tissue, striated skeletal muscle tissue, smooth muscle tissue, bone, vasculature, and nerve tissue.

  5. An electrically tunable imaging system with separable focus and zoom functions using composite liquid crystal lenses.

    Science.gov (United States)

    Chen, Ming-Syuan; Chen, Po-Ju; Chen, Michael; Lin, Yi-Hsin

    2014-05-19

    We demonstrated an electrically tunable optical image system with separable focus function and zoom function based on three tunable focusing composite liquid crystal (LC) lenses. One LC lens in charge of the focus function helps to maintain the formed image at the same position and the other two LC lenses in charge of zoom function assist to continuously form an image at image sensor with tunable magnification of image size. The detail optical mechanism is investigated and the concept is demonstrated experimentally. The magnifications of the images can be switched continuously for the target in a range between 10 cm and 100 cm. The optical zoom ratio of this system maintains a constant~6.5:1 independent of the object distance. This study provides not only a guideline to design the image system with an electrically optical zoom, but also provide an experimental process to show how to operate the tunable focusing lenses in such an image system.

  6. Study of the Electrical Double Layer of a Spherical Micelle:Functional Theoretical Approach

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    By using the iterative method in functional theory, an analytic expression of the Poisson-Boltzmann equation (PB eq.), which describes the distribution of the potential of electrical double layer of a spherical micelle, has been carried out under the general potential condition for the first time. The method also can give the radius, the surface potential, and the thickness of the layer.

  7. Control of thumb force using surface functional electrical stimulation and muscle load sharing

    NARCIS (Netherlands)

    Westerveld, A.J.; Schouten, A.C.; Veltink, P.H.; Van der Kooij, H.

    2013-01-01

    Background Stroke survivors often have difficulties in manipulating objects with their affected hand. Thumb control plays an important role in object manipulation. Surface functional electrical stimulation (FES) can assist movement. We aim to control the 2D thumb force by predicting the sum of indiv

  8. Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method

    Directory of Open Access Journals (Sweden)

    Hai-peng Wang

    2017-01-01

    Full Text Available Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy. A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method. Through a series of novel design concepts, including the integration of a detecting circuit and an analog-to-digital converter, a miniaturized functional electrical stimulation circuit technique, a low-power super-regeneration chip for wireless receiving, and two wearable armbands, a prototype system has been established with reduced size, power, and overall cost. Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects, the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy. Test results showed that wrist flexion/extension, hand grasp, and finger extension could be reproduced with high accuracy and low latency. This system can build a bridge of information transmission between healthy limbs and paralyzed limbs, effectively improve voluntary participation of hemiplegic patients, and elevate efficiency of rehabilitation training.

  9. Effects of the electric field on the properties of ZnO-graphene composites: a density functional theory study.

    Science.gov (United States)

    Geng, Wei; Zhao, Xuefei; Zan, Wenyan; Liu, Huanxiang; Yao, Xiaojun

    2014-02-28

    In this work, the effects of the electric field on the properties of ZnO-graphene composites were theoretically studied using density functional theory calculations. Three types of ZnO-graphene composites including composites of pristine graphene, graphene with defects as well as graphene oxide and a ZnO bilayer were studied. We calculated and analyzed the binding energies, charge transfer, band structures and work functions of the above composites under the external electric fields. The DFT calculation results demonstrate that the binding energies are sensitive to the electric field, and increasing the external electric field gives rise to stronger binding energies. The extent of charge transfer is correlated with the magnitude of the external electric field, but the band gaps are hardly affected by the external electric field. The work functions vary depending on the different structures of the composites and surface sides, and they are also tunable by the external electric field.

  10. Controlling the electrical conductive network formation of polymer nanocomposites via polymer functionalization.

    Science.gov (United States)

    Gao, Yangyang; Wu, Youping; Liu, Jun; Zhang, Liqun

    2016-12-06

    By adopting coarse-grained molecular dynamics simulations, the effect of polymer functionalization on the relationship between the microstructure and the electric percolation probability of nanorod filled polymer nanocomposites has been investigated. At a low chain functionalization degree, the nanorods in the polymer matrix form isolated aggregates with a local order structure. At a moderate chain functionalization degree, the local order structure of the nanorod aggregate is gradually broken up. Meanwhile, excessive functionalization chain beads can connect the isolated aggregates together, which leads to the maximum size of nanorod aggregation. At a high chain functionalization degree, it forms a single nanorod structure in the matrix. As a result, the highest percolation probability of the materials appears at the moderate chain functionalization degree, which is attributed to the formation of the tightly connected nanorod network by analyzing the main cluster. In addition, this optimum chain functionalization degree exists at two chain functionalization modes (random and diblock). Lastly, under the tensile field, even though the contact distance between nanorods nearly remains unchanged, the topological structure of the percolation network is broken down. While under the shear field, the contact distance between nanorods increases and the topological structure of the percolation network is broken down, which leads to a decrease in the percolation probability. In total, the topological structure of the percolation network dominates the percolation probability, which is not a necessary connection with the contact distance between nanorods. In summary, this work presents further understanding of the electric conductive properties of nanorod-filled nanocomposites with functionalized polymers.

  11. Silicon photonic integrated circuits with electrically programmable non-volatile memory functions.

    Science.gov (United States)

    Song, J-F; Lim, A E-J; Luo, X-S; Fang, Q; Li, C; Jia, L X; Tu, X-G; Huang, Y; Zhou, H-F; Liow, T-Y; Lo, G-Q

    2016-09-19

    Conventional silicon photonic integrated circuits do not normally possess memory functions, which require on-chip power in order to maintain circuit states in tuned or field-configured switching routes. In this context, we present an electrically programmable add/drop microring resonator with a wavelength shift of 426 pm between the ON/OFF states. Electrical pulses are used to control the choice of the state. Our experimental results show a wavelength shift of 2.8 pm/ms and a light intensity variation of ~0.12 dB/ms for a fixed wavelength in the OFF state. Theoretically, our device can accommodate up to 65 states of multi-level memory functions. Such memory functions can be integrated into wavelength division mutiplexing (WDM) filters and applied to optical routers and computing architectures fulfilling large data downloading demands.

  12. [Real-time Gait Training System with Embedded Functional Electrical Stimulation].

    Science.gov (United States)

    Gu, Linyan; Ruan, Zhaomin; Jia, Guifeng; Xla, Jing; Qiu, Lijian; Wu, Changwang; Jin, Xiaoqing; Ning, Gangmin

    2015-07-01

    To solve the problem that mostly gait analysis is independent from the treatment, this work proposes a system that integrates the functions of gait training and assessment for foot drop treatment. The system uses a set of sensors to collect gait parameters and designes multi-mode functional electrical stimulators as actuator. Body area network technology is introduced to coordinate the data communication and execution of the sensors and stimulators, synchronize the gait analysis and foot drop treatment. Bluetooth 4.0 is applied to low the power consumption of the system. The system realizes the synchronization of treatment and gait analysis. It is able to acquire and analyze the dynamic parameters of ankle, knee and hip in real-time, and treat patients by guiding functional electrical stimulation delivery to the specific body locations of patients.

  13. Reconfigurable anisotropy and functional transformations with VO$_{2}$-based metamaterial electric circuits

    CERN Document Server

    Savo, Salvatore; Castaldi, Giuseppe; Moccia, Massimo; Galdi, Vincenzo; Ramanathan, Shriram; Sato, Yuki

    2014-01-01

    We demonstrate an innovative multifunctional artificial material that combines exotic metamaterial properties and the environmentally responsive nature of phase change media. The tunable metamaterial is designed with the aid of two interwoven coordinate-transformation equations and implemented with a network of thin film resistors and vanadium dioxide ($VO_{2}$). The strong temperature dependence of $VO_{2}$ electrical conductivity results in a relevant modification of the resistor network behavior, and we provide experimental evidence for a reconfigurable metamaterial electric circuit (MMEC) that not only mimics a continuous medium but is also capable of responding to thermal stimulation through dynamic variation of its spatial anisotropy. Upon external temperature change the overall effective functionality of the material switches between a "truncated-cloak" and "concentrator" for electric currents. Possible applications may include adaptive matching resistor networks, multifunctional electronic devices, an...

  14. Study on the electric double layer of a cylindrical reverse micelle with functional theoretical approach

    Institute of Scientific and Technical Information of China (English)

    WANG; Zhengwu; GUO; Baomin; ZHANG; Gexin

    2006-01-01

    The iterative method in functional analysis is applied to looking for a solution of the Poisson-Boltzmann equation in order to describe the problems of the distribution of the potentials in the electric double layer (EDL) inside the water pool for a cylindrical inverse micelle. Potentials as a function of the position of a particular point in EDL are computed, which display a quantitative is also shown that in the higher-potential range the iterative calculations can give more accurate results. These results indicate the utility of this functional analysis technique in the description of the properties of EDL for a cylindrical inverse micelle.

  15. Vibration Prediction Method of Electric Machines by using Experimental Transfer Function and Magnetostatic Finite Element Analysis

    Science.gov (United States)

    Saito, A.; Kuroishi, M.; Nakai, H.

    2016-09-01

    This paper concerns the noise and structural vibration caused by rotating electric machines. Special attention is given to the magnetic-force induced vibration response of interior-permanent magnet machines. In general, to accurately predict and control the vibration response caused by the electric machines, it is inevitable to model not only the magnetic force induced by the fluctuation of magnetic fields, but also the structural dynamic characteristics of the electric machines and surrounding structural components. However, due to complicated boundary conditions and material properties of the components, such as laminated magnetic cores and varnished windings, it has been a challenge to compute accurate vibration response caused by the electric machines even after their physical models are available. In this paper, we propose a highly-accurate vibration prediction method that couples experimentally-obtained discrete structural transfer functions and numerically-obtained distributed magnetic-forces. The proposed vibration synthesis methodology has been applied to predict vibration responses of an interior permanent magnet machine. The results show that the predicted vibration response of the electric machine agrees very well with the measured vibration response for several load conditions, for wide frequency ranges.

  16. Comprehension of the Electric Polarization as a Function of Low Temperature

    Science.gov (United States)

    Liu, Changshi

    2017-01-01

    Polarization response to warming plays an increasingly important role in a number of ferroelectric memory devices. This paper reports on the theoretical explanation of the relationship between polarization and temperature. According to the Fermi-Dirac distribution, the basic property of electric polarization response to temperature in magnetoelectric multiferroic materials is theoretically analyzed. The polarization in magnetoelectric multiferroic materials can be calculated by low temperature using a phenomenological theory suggested in this paper. Simulation results revealed that the numerically calculated results are in good agreement with experimental results of some inhomogeneous multiferroic materials. Numerical simulations have been performed to investigate the influences of both electric and magnetic fields on the polarization in magnetoelectric multiferroic materials. Furthermore, polarization behavior of magnetoelectric multiferroic materials can be predicted by low temperature, electric field and magnetic induction using only one function. The calculations offer an insight into the understanding of the effects of heating and magnetoelectric field on electrical properties of multiferroic materials and offer a potential to use similar methods to analyze electrical properties of other memory devices.

  17. Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs

    Science.gov (United States)

    Bloomberg, Jacob; Reschke, Millard; Mulavara, Ajitkumar; Wood, Scott; Serrador, Jorge; Fiedler, Matthew; Kofman, Igor; Peters, Brian T.; Cohen, Helen

    2012-01-01

    Crewmembers returning from long-duration space flight face significant challenges due to the microgravity-induced inappropriate adaptations in balance/ sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic resonance to enhance the brain s ability to detect signals from the balance organs of the inner ear and use them for rapid improvement in balance skill, especially when combined with balance training exercises. This method involves a stimulus delivery system that is wearable/portable providing imperceptible electrical stimulation to the balance organs of the human body. Stochastic resonance (SR) is a phenomenon whereby the response of a nonlinear system to a weak periodic input signal is optimized by the presence of a particular non-zero level of noise. This phenomenon of SR is based on the concept of maximizing the flow of information through a system by a non-zero level of noise. Application of imperceptible SR noise coupled with sensory input in humans has been shown to improve motor, cardiovascular, visual, hearing, and balance functions. SR increases contrast sensitivity and luminance detection; lowers the absolute threshold for tone detection in normal hearing individuals; improves homeostatic function in the human blood pressure regulatory system; improves noise-enhanced muscle spindle function; and improves detection of weak tactile stimuli using mechanical or electrical stimulation. SR noise has been shown to improve postural control when applied as mechanical noise to the soles of the feet, or when applied as electrical noise at the knee and to the back muscles.

  18. Tremor suppression using functional electrical stimulation: a comparison between digital and analog controllers.

    Science.gov (United States)

    Gillard, D M; Cameron, T; Prochazka, A; Gauthier, M J

    1999-09-01

    In this study, we compared digital and analog versions of a functional electrical stimulator designed to suppress tremor. The device was based on a closed-loop control system designed to attenuate movements in the tremor frequency range, without significantly affecting slower, voluntary movements. Testing of the digital filter was done on three patients with Parkinsonian tremor and the results compared to those of a functional electrical stimulation device based on an analog filter evaluated in a previous study. Additional testing of both the analog and digital filters was done on three subjects with no neurological impairment performing tremor-like movements and slow voluntary movements. We found that the digital controller provided a mean attenuation of 84%, compared to 65% for the analog controller.

  19. An empirically constructed dynamic electric dipole polarizability function of magnesium and its applications

    CERN Document Server

    Babb, James F

    2015-01-01

    The dynamic electric dipole polarizability function for the magnesium atom is formed by assembling the atomic electric dipole oscillator strength distribution from combinations of theoretical and experimental data for resonance oscillator strengths and for photoionization cross sections of valence and inner shell electrons. Consistency with the oscillator strength (Thomas-Reiche-Kuhn) sum rule requires the adopted principal resonance line oscillator strength to be several percent lower than the values given in two critical tabulations, though the value adopted is consistent with a number of theoretical determinations. The static polarizability is evaluated. Comparing the resulting dynamic polarizability as a function of photon energy with more elaborate calculations reveals the contributions of inner shell electron excitations. The present results are applied to calculate the long-range interactions between two and three magnesium atoms and the interaction between a magnesium atom and a perfectly conducting m...

  20. Colour-electric spectral function at next-to-leading order

    CERN Document Server

    Burnier, Y; Langelage, J; Mether, L

    2010-01-01

    The spectral function related to the correlator of two colour-electric fields along a Polyakov loop determines the momentum diffusion coefficient of a heavy quark near rest with respect to a heat bath. We compute this spectral function at next-to-leading order, O(alpha_s^2), in the weak-coupling expansion. The high-frequency part of our result (omega >> T), which is shown to be temperature-independent, is accurately determined thanks to asymptotic freedom; the low-frequency part of our result (omega 0. We also evaluate the colour-electric Euclidean correlator, which could be directly compared with lattice simulations. As an aside we determine the Euclidean correlator in the lattice strong-coupling expansion, showing that through a limiting procedure it can in principle be defined also in the confined phase of pure Yang-Mills theory, even if a practical measurement could be very noisy there.

  1. Applications of Elliptic Integral and Elliptic Function to Electric Power Cable Problems

    Science.gov (United States)

    Watanabe, Kazuo

    The paper proposes an application of elliptic function to a new measuring method of electric resistivity of outer-semiconductive layer of XLPE cable. The new measuring method may substitute the conventional method. The resistivity can be obtained easily by measuring resistance between two electrodes which are attached to a circumferential edge on one side of the outer-semiconductive layer of a cable core sample. The solution process is applicable to heat conduction as well as hydromechanics.

  2. Development of BION(TM) Technology for Functional Electrical Stimulation: Bidirectional Telemetry

    Science.gov (United States)

    2007-11-02

    channel electrical interfaces that can be injected into one or more muscles through a 12-gauge hypodermic needle. They receive power and command signals...microminiature implants (Figure 1), each of which provides a long-term, wireless interface between an electronic controller and a neural function...and power implicit in the injectable BION package [9]: • Myoelectric signals (EMG) will be detected by the existing electrodes and amplified

  3. Effectiveness of neuromuscular electrical stimulation in the functional knee rehabilitation in soldiers

    OpenAIRE

    R. Castillo-Lozano

    2015-01-01

    Background: The versatility of military physical therapist practice enables them not only to diagnose knee injuries but also to provide a wide range of definitive care and rehabilitation, reducing the need for costly evacuation. The aim this study was to evaluate the effectiveness of interventions by Neuromuscular Electrical Stimulation (NMES) in the functional knee rehabilitation in soldiers and describe the main predictors and determinants in each intervention. Methods: A systematic search ...

  4. Functioning of the Finnish electricity wholesale markets; Saehkoen tukkumarkkinan toimivuus Suomessa

    Energy Technology Data Exchange (ETDEWEB)

    Vehvilainen, I.; Broeckl, M.; Hakala, L.; Vanhanen, J.

    2012-12-15

    The purpose of common Nordic electricity market has been to increase competition and efficiency. Market seems to be moving to the opposite direction in the 2010s. Wholesale market has become more fragmented as the market is split to larger number of price areas more often. Poor functioning of the wholesale markets is also the largest contributor to problems in the retail market. Politicians, market regulators, transmission system operators, and market players need to take action to improve the functioning of the market. Separation of price areas reduces competition in all market areas. The Finnish wholesale market is moderately or highly concentrated when Finland is separated from other price areas. Concentration is moderate, if all production capacity is considered. If only price setting hydropower and condensing power capacity are considered, the market is highly concentrated. High concentration can provide opportunities for the biggest producers to use strategic bidding to increase market prices. Larger number of price areas has reduced competition and liquidity with the financial area price products or CfDs. Poor functioning of CfD markets is emphasized by the low competition within the price areas. Bottlenecks between market areas create income for the Transmission System Operators (TSOs) that are responsible of the border transmissions. TSOs have no economic incentives to maintain and repair the border transmission lines, which seems peculiar when compared to e.g. regulation of electricity distribution companies. Finnish Fingrid shows a good example on transparent disclosure of received income and how the accrued funds are used. Import of electricity from Russia to Finland has been reduced since the end of 2011 because of the changes made in the Russian electricity market. Market liberalization in Russia has lead to a market structure that is different from the Nordic markets. Despite the differences, the two markets are becoming more integrated as the

  5. A multi-pad electrode based functional electrical stimulation system for restoration of grasp

    Directory of Open Access Journals (Sweden)

    Malešević Nebojša M

    2012-09-01

    Full Text Available Abstract Background Functional electrical stimulation (FES applied via transcutaneous electrodes is a common rehabilitation technique for assisting grasp in patients with central nervous system lesions. To improve the stimulation effectiveness of conventional FES, we introduce multi-pad electrodes and a new stimulation paradigm. Methods The new FES system comprises an electrode composed of small pads that can be activated individually. This electrode allows the targeting of motoneurons that activate synergistic muscles and produce a functional movement. The new stimulation paradigm allows asynchronous activation of motoneurons and provides controlled spatial distribution of the electrical charge that is delivered to the motoneurons. We developed an automated technique for the determination of the preferred electrode based on a cost function that considers the required movement of the fingers and the stabilization of the wrist joint. The data used within the cost function come from a sensorized garment that is easy to implement and does not require calibration. The design of the system also includes the possibility for fine-tuning and adaptation with a manually controllable interface. Results The device was tested on three stroke patients. The results show that the multi-pad electrodes provide the desired level of selectivity and can be used for generating a functional grasp. The results also show that the procedure, when performed on a specific user, results in the preferred electrode configuration characteristics for that patient. The findings from this study are of importance for the application of transcutaneous stimulation in the clinical and home environments.

  6. TECHNICAL NOTE: Spun-cast micromolding for etchless micropatterning of electrically functional PDMS structures

    Science.gov (United States)

    McClain, Maxine A.; La Placa, Michelle C.; Allen, Mark G.

    2009-10-01

    Polydimethylsiloxane (PDMS) is widely used in bioMEMS applications; however, patterning of this material to form complex structures is often challenging. Chemical etches are typically ineffective due to the inertness of the material. Plasma processing of bulk material can be time intensive and presents concerns regarding the mechanical properties of the post-etched polymer due to etch-induced cross-linking of surrounding material. Presented in this paper, the etchless process of spun-cast micromolding (SCμM) is used to create an array of patterned, PDMS, electrical microcables. The microcables are arranged in a net-like array and incorporate electrical functionality. The geometries fabricated with these techniques include straight and sinusoidal microcables. In addition to the cables themselves, specific regions of the cables' top insulating layer can also be patterned using a hierarchical application of the SCμM process, creating exposed electrical access sites useful as electrical access points for electrophysiological applications. The SCμM process is a simple, relatively rapid technique that can be used to make highly compliant electronic structures with patternable geometries.

  7. Materials Comparison of Cutting Tools Functional Parts for Cutting of Electrical Engineering Sheets

    Directory of Open Access Journals (Sweden)

    Jan ZLÁMALÍK

    2012-06-01

    Full Text Available Paper concerns the comparison of functional materials parts of cutting tools used for the production of stator and rotor sheets in the electrical industry from point of view of their life. Alternatives and the properties of metal used for the production of stator and rotor components in electrical rotating machines are analysed. The main factors affecting the life of cutting tools of functional parts are analysed, one of the most important is the cutting tool functional parts material itself. Comparison of three variants of the cuttong tool funkcional parts material – 19 436 tool steel (chrome steel according to the Czech State Standard 41 9436, 19 830 high speed steel according to the Czech State Standard 41 9830 and a special powder metallurgy product – ledeburite tool steel Vanadis 10. Useful lifes of the functional components of individual cutting tools performances can be calculated from the theoretical lifes by their multiplying the coefficients of the tool design and the cutting edges shape complexity.

  8. A new method to determine the electrical transfer function of the human thorax.

    Science.gov (United States)

    Goldberger, Jeffrey J; Subacius, Haris; Sen-Gupta, Indranil; Johnson, David; Kadish, Alan H; Ng, Jason

    2007-12-01

    Traditional analyses have assumed that cardiac electrical activity is reflected on the surface ECG without distortion as the signal passes through the body tissues. This study aims to explore the frequency dependence of thoracic attenuation of surface-recorded intracardiac electrical activity. Twenty patients (14 men, 55 +/- 15 yr of age) undergoing electrophysiological study were enrolled. Rectangular unipolar stimuli were applied from a catheter positioned in the right ventricular apical area and another in the posteroseptal area without contact with the myocardium. An orthogonal Frank-lead surface ECG and a unipolar intracardiac electrogram near the pacing site were recorded. Frequency domain characteristics of the signal-averaged pacing impulses were analyzed. Linear regression analysis showed significant frequency-dependent attenuation in the magnitude transfer functions (R(2) = 0.84-0.89, P signal-averaged ECGs from 33 subjects showed differences in the attenuation of P and T waves relative to the QRS.

  9. Electric field gradients of transition metal complexes from density functional theory: assessment of functionals, geometries and basis sets.

    Science.gov (United States)

    Bjornsson, Ragnar; Bühl, Michael

    2010-06-14

    Electric field gradients (EFGs) were computed for the first-row transition metal nuclei in Cr(C(6)H(6))(CO)(3), MnO(3)F, Mn(CO)(5)H, MnCp(CO)(3), Co(CO)(4)H, Co(CO)(3)(NO) and VCp(CO)(4), for which experimental gas-phase data (in form of nuclear quadrupole coupling constants) are available from microwave spectroscopy. A variety of exchange-correlation functionals were assessed, among which range-separated hybrids (such as CAM-B3LYP or LC-omegaPBE) perform best, followed by global hybrids (such as B3LYP and PBE0) and gradient-corrected functionals (such as BP86). While large basis sets are required on the metal atom for converged EFGs, smaller basis sets can be employed on the ligands. In most cases, EFGs show little sensitivity toward the geometrical parameters.

  10. Functional electrical stimulation therapy improves grasping in chronic cervical spinal cord injury: Two case studies

    Directory of Open Access Journals (Sweden)

    Miller Rosalynn C.

    2008-01-01

    Full Text Available OBJECTIVE AND IMPORTANCE: To present case studies of two individuals with chronic cervical spinal cord injury (SCI who participated in functional electrical stimulation (FES therapy with the objective to restore voluntary grasp function. CLINICAL PRESENTATION: Both individuals (right hand dominant males, age 24 and 31 had a sustained a cervical SCI (C6 and C4-5, respectively at least 8 years prior to participation in this study. INTERVENTION: Both individuals participated in an individualized FES therapy program for 6 weeks. FES therapy was administered through a regimen of three, one-hour sessions, per week for three months. A single arm of each participant (n = 2 was treated. FES therapy is an integrative intervention strategy combining muscle strengthening, functional movement training and stretching. The participant's hand movement abilities were assessed pre and post FES therapy using the Manual Muscle Test (MMT, a modified Sollerman Hand Function Test (mSHFT, and the Reach, Grasp, Transport and Release Task (RGTR. DISCUSSION: As the injuries of participants in the current study were chronic and thus neurologically stable, no spontaneous improvements/recovery in hand function was expected. However, FES as part of an integrated therapeutic approach affected restoration and improvement of hand function in both participants. CONCLUSION: The concurrent improvement in strength, integrated motor function and object contact following FES therapy, demonstrated that there is potential for affecting change in hand function of individuals with chronic SCI.

  11. Simulation of Electricity Demand Function in Agricultural Sector: An Application of Genetic Algorithm (Case Study: Electricity-Fed Wells of Iran

    Directory of Open Access Journals (Sweden)

    Hossein Sadeghi

    2014-11-01

    Full Text Available Due to several problems arisen from consumption of gas oil, it is necessary to electricity substitute fossil fuels in agriculture wells in Iran. Problems such as lack of opportune and adequate supply of fuel, air and soil pollution, noise pollution and huge costs of installation, operation and maintenance imply the necessity of replacing gas oil systems by electricity-consuming ones in agriculture sector of Iran.However, it is essential to study on the demand of electricity, nowadays, substituting other energy sources.As water wells are the main electricity consumersin agriculture sector, the estimation of energy demand function would be beneficial for policy makers to achieve their goals. The present paper investigates on energy demand function in agriculture sector of Iran.Genetic algorithm techniques are appliedto estimate electricity demand in agricultural sector in three forms: linear, quadratic and exponential equations. Based on the conventional criteria, the exponential model is selected as the best model for estimation. Furthermore, electricity demand of agricultural sector is forecasted under three scenarios for years next three years.

  12. Functional Modeling of Perspectives on the Example of Electric Energy Systems

    DEFF Research Database (Denmark)

    Heussen, Kai

    2009-01-01

    The integration of energy systems is a proven approach to gain higher overall energy efficiency. Invariably, this integration will come with increasing technical complexity through the diversification of energy resources and their functionality. With the integration of more fluctuating renewable ...... which enables a reflection on system integration requirements independent of particular technologies. The results are illustrated on examples related to electric energy systems.......The integration of energy systems is a proven approach to gain higher overall energy efficiency. Invariably, this integration will come with increasing technical complexity through the diversification of energy resources and their functionality. With the integration of more fluctuating renewable...... energies higher system flexibility will also be necessary. One of the challenges ahead is the design of control architecture to enable the flexibility and to handle the diversity. This paper presents an approach to model heterogeneous energy systems and their control on the basis of purpose and functions...

  13. Hawaiian Electric Advanced Inverter Grid Support Function Laboratory Validation and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Austin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Nagarajan, Adarsh [National Renewable Energy Lab. (NREL), Golden, CO (United States); Prabakar, Kumar [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gevorgian, Vahan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lundstrom, Blake [National Renewable Energy Lab. (NREL), Golden, CO (United States); Nepal, Shaili [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hoke, Anderson [National Renewable Energy Lab. (NREL), Golden, CO (United States); Asano, Marc [Hawaiian Electric Company, Honolulu, HI (United States); Ueda, Reid [Hawaiian Electric Company, Honolulu, HI (United States); Shindo, Jon [Hawaiian Electric Company, Honolulu, HI (United States); Kubojiri, Kandice [Hawaiian Electric Company, Honolulu, HI (United States); Ceria, Riley [Hawaiian Electric Company, Honolulu, HI (United States); Ifuku, Earle [Hawaiian Electric Company, Honolulu, HI (United States)

    2016-12-01

    The objective for this test plan was to better understand how to utilize the performance capabilities of advanced inverter functions to allow the interconnection of distributed energy resource (DER) systems to support the new Customer Self-Supply, Customer Grid-Supply, and other future DER programs. The purpose of this project was: 1) to characterize how the tested grid supportive inverters performed the functions of interest, 2) to evaluate the grid supportive inverters in an environment that emulates the dynamics of O'ahu's electrical distribution system, and 3) to gain insight into the benefits of the grid support functions on selected O'ahu island distribution feeders. These goals were achieved through laboratory testing of photovoltaic inverters, including power hardware-in-the-loop testing.

  14. Electrical characterization of DNA-functionalized solid state nanopores for bio-sensing

    Energy Technology Data Exchange (ETDEWEB)

    Mussi, V; Fanzio, P; Repetto, L; Firpo, G; Valbusa, U [Nanomed Labs, Physics Department, University of Genova, and Nanobiotechnologies, National Institute of Cancer Research (IST), Largo R Benzi, 10 Genova, 16132 (Italy); Scaruffi, P; Stigliani, S; Tonini, G P [Translational Pediatric Oncology, National Institute for Cancer Research (IST), Largo R Benzi, 10 Genova, 16132 (Italy); Menotta, M; Magnani, M, E-mail: mussi@fisica.unige.i [Department of Biomolecular Sciences, University of Urbino ' Carlo Bo' , Via Saffi 2, 61029 Urbino (Italy)

    2010-11-17

    We present data concerning the electrical properties of a class of biosensor devices based on bio-functionalized solid state nanopores able to detect different kinds of interactions between probe molecules, chemically attached to the pore surface, and target molecules present in solution and electrophoretically drawn through the nanometric channel. The great potentiality of this approach resides in the fact that the functionalization of a quite large pore (up to 50-60 nm) allows a sufficient diameter reduction for the attainment of a single molecule sensing dimension and selective activation, without the need for further material deposition, such as metal or oxides, or localized surface modification. The results indicate that it will be possible, in the near future, to conceive and design devices for parallel analysis of biological samples made of arrays of nanopores differently functionalized, fabricated by standard lithographic techniques, with important applications in the field of molecular diagnosis.

  15. Electrical characterization of DNA-functionalized solid state nanopores for bio-sensing

    Science.gov (United States)

    Mussi, V.; Fanzio, P.; Repetto, L.; Firpo, G.; Scaruffi, P.; Stigliani, S.; Menotta, M.; Magnani, M.; Tonini, G. P.; Valbusa, U.

    2010-11-01

    We present data concerning the electrical properties of a class of biosensor devices based on bio-functionalized solid state nanopores able to detect different kinds of interactions between probe molecules, chemically attached to the pore surface, and target molecules present in solution and electrophoretically drawn through the nanometric channel. The great potentiality of this approach resides in the fact that the functionalization of a quite large pore (up to 50-60 nm) allows a sufficient diameter reduction for the attainment of a single molecule sensing dimension and selective activation, without the need for further material deposition, such as metal or oxides, or localized surface modification. The results indicate that it will be possible, in the near future, to conceive and design devices for parallel analysis of biological samples made of arrays of nanopores differently functionalized, fabricated by standard lithographic techniques, with important applications in the field of molecular diagnosis.

  16. Electrical Properties of Conductive Cotton Yarn Coated with Eosin Y Functionalized Reduced Graphene Oxide.

    Science.gov (United States)

    Kim, Eunju; Arul, Narayanasamy Sabari; Han, Jeong In

    2016-06-01

    This study reports the fabrication and investigation of the electrical properties of two types of conductive cotton yarns coated with eosin Y or eosin B functionalized reduced graphene (RGO) and bare graphene oxide (GO) using dip-coating method. The surface morphology of the conductive cotton yarn coated with reduced graphene oxide was observed by Scanning Electron Microscope (SEM). Due to the strong electrostatic attractive forces, the negatively charged surface such as the eosin Y functionalized reduced graphene oxide or bare GO can be easily coated to the positively charged polyethyleneimine (PEI) treated cotton yarn. The maximum current for the conductive cotton yarn coated with eosin Y functionalized RGO and bare GO with 20 cycles repetition of (5D + R) process was found to be 793.8 μA and 3482.8 μA. Our results showed that the electrical conductivity of bare GO coated conductive cotton yarn increased by approximately four orders of magnitude with the increase in the dipping cycle of (5D+R) process.

  17. Non-Invasive Electrical Brain Stimulation Montages for Modulation of Human Motor Function.

    Science.gov (United States)

    Curado, Marco; Fritsch, Brita; Reis, Janine

    2016-02-04

    Non-invasive electrical brain stimulation (NEBS) is used to modulate brain function and behavior, both for research and clinical purposes. In particular, NEBS can be applied transcranially either as direct current stimulation (tDCS) or alternating current stimulation (tACS). These stimulation types exert time-, dose- and in the case of tDCS polarity-specific effects on motor function and skill learning in healthy subjects. Lately, tDCS has been used to augment the therapy of motor disabilities in patients with stroke or movement disorders. This article provides a step-by-step protocol for targeting the primary motor cortex with tDCS and transcranial random noise stimulation (tRNS), a specific form of tACS using an electrical current applied randomly within a pre-defined frequency range. The setup of two different stimulation montages is explained. In both montages the emitting electrode (the anode for tDCS) is placed on the primary motor cortex of interest. For unilateral motor cortex stimulation the receiving electrode is placed on the contralateral forehead while for bilateral motor cortex stimulation the receiving electrode is placed on the opposite primary motor cortex. The advantages and disadvantages of each montage for the modulation of cortical excitability and motor function including learning are discussed, as well as safety, tolerability and blinding aspects.

  18. Influence of laser pulse on the autocorrelation function of H in a strong electric field

    Institute of Scientific and Technical Information of China (English)

    Lifei Wang; Guangcan Yang

    2009-01-01

    The autocorrelation function of electronic wave packet of hydrogen atom in a strong electric field below the zero-field ionization threshold is investigated in the formalism of semiclassical theory. It is found that the autocorrelation depends on the applied laser pulse significantly. In the case of narrow laser pulse, the reviving peaks in the autocorrelation can be attributed to the closed orbits of electrons, which are related to the classical dynamics of the system. But this correspondence is wiped out with increasing the laser width because of the interference among the adjacent reviving peaks.

  19. Constraining the electric dipole photon strength function in {sup 130}Te

    Energy Technology Data Exchange (ETDEWEB)

    Isaak, J.; Loeher, B.; Savran, D.; Silva, J. [ExtreMe Matter Institute EMMI and Research Division, Darmstadt (Germany); FIAS, Frankfurt (Germany); Ahmed, M.W.; Kelley, J.H.; Tornow, W.; Weller, H.R. [Department of Physics, Duke University, TUNL (United States); Beller, J.; Pietralla, N.; Romig, C.; Zweidinger, M. [Institut fuer Kernphysik, TU Darmstadt (Germany); Glorius, J.; Sonnabend, K. [Institut fuer Angewandte Physik, Goethe-Universitaet Frankfurt (Germany); Krticka, M. [Faculty of Mathematics and Physics, Charles University, Prague (Czech Republic); Rusev, G. [Chemistry Division, LANL (United States); Scheck, M. [School of Engineering, University of the West of Scotland (United Kingdom); Tonchev, A.P. [Physics Division, LLNL (United States)

    2014-07-01

    The decay properties of photo-excited states in {sup 130}Te have been investigated by means of Nuclear Resonance Fluorescence experiments at the Darmstadt High Intensity Photon Setup (DHIPS) and the High Intensity γ-ray Source (HIγS). The combination of continuous-energy bremsstrahlung on the one hand and the quasi-monoenergetic and linearly polarized photon beam on the other enables a detailed insight into the photoabsorption cross section and the decay behavior of spin-1 states. Comparing these results to simulations within the statistical model allow for constraining the electric dipole photon strength function (E1-PSF). Results are presented and discussed.

  20. A Regularization Process for Electrical Impedance Equation Employing Pseudoanalytic Function Theory

    Directory of Open Access Journals (Sweden)

    Cesar Marco Antonio Robles Gonzalez

    2014-01-01

    Full Text Available The electrical impedance equation is considered an ill-posed problem where the solution to the forward problem is more easy to achieve than the inverse problem. This work tries to improve convergence in the forward problem method, where the Pseudoanalytic Function Theory by means of the Taylor series in formal powers is used, incorporating a regularization method to make a solution more stable and to obtain better convergence. In addition, we include a comparison between the designed algorithms that perform proposed method with and without a regularization process and the autoadjustment parameter for this regularization process.

  1. Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs

    Science.gov (United States)

    Bloomberg, Jacob; Reschke, Millard; Mulavara, Ajitkumar; Wood, Scott; Serrador, Jorge; Fiedler, Matthew; Kofman, Igor; Peters, Brian T.; Cohen, Helen

    2012-01-01

    Crewmembers returning from long-duration space flight face significant challenges due to the microgravity-induced inappropriate adaptations in balance/sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic resonance to enhance the brain's ability to detect signals from the balance organs of the inner ear and use them for rapid improvement in balance skill, especially when combined with balance training exercises. This method involves a stimulus delivery system that is wearable/portable and provides imperceptible electrical stimulation to the balance organs of the human body. Stochastic resonance (SR) is a phenomenon whereby the response of a nonlinear system to a weak periodic input signal is optimized by the presence of a particular non-zero level of noise. This phenomenon of SR is based on the concept of maximizing the flow of information through a system by a non-zero level of noise. Application of imperceptible SR noise coupled with sensory input in humans has been shown to improve motor, cardiovascular, visual, hearing, and balance functions. SR increases contrast sensitivity and luminance detection; lowers the absolute threshold for tone detection in normal hearing individuals; improves homeostatic function in the human blood pressure regulatory system; improves noise-enhanced muscle spindle function; and improves detection of weak tactile stimuli using mechanical or electrical stimulation. SR noise has been shown to improve postural control when applied as mechanical noise to the soles of the feet, or when applied as electrical noise at the knee and to the back muscles. SR using imperceptible stochastic electrical stimulation of the vestibular system (stochastic vestibular stimulation, SVS) applied to normal subjects has shown to improve the degree of association between the weak input periodic signals introduced via venous blood pressure receptors and the heart-rate responses. Also, application of SVS over 24

  2. Modeling Mechanical and Electrical Uncertain Systems using Functions of Robust Control MATLAB Toolbox®3

    Directory of Open Access Journals (Sweden)

    Mohammed Tawfik Hussein

    2015-04-01

    Full Text Available Uncertainty is inherent property of all real life control systems, and this is due to that there is nothing constant practically; all parameters are going to change under some environmental circumstances, therefore control engineers must not ignore this changing since it can affect the behavior and the performance of the system. In this paper a critical research method for modeling uncertain systems is demonstrated with the utilization of built in robust control Matlab Toolbox®3 functions. Good results were obtained for testing the stability of interval linear time invariant systems. Finally mechanical and electrical uncertain systems were implemented as practical example to validate the uncertainty.

  3. Sensor-driven four-channel stimulation of paretic leg: functional electrical walking therapy.

    Science.gov (United States)

    Kojović, Jovana; Djurić-Jovicić, Milica; Dosen, Strahinja; Popović, Mirjana B; Popović, Dejan B

    2009-06-30

    This study introduces a Functional Electrical Therapy (FET) system based on sensor-driven electrical stimulation for the augmentation of walking. The automatic control relates to the timing of stimulation of four muscles. The sensor system comprises accelerometers and force-sensing resistors. The automatic control implements IF-THEN rules designed by mapping of sensors and muscle activation patterns. The new system was tested in 13 acute stroke patients assigned to a FET group or a control (CON) group. Both groups were treated with a standard rehabilitation program and 45min of walking daily for 5 days over the course of 4 weeks. The FET group received electrical stimulation during walking. The Fugl-Meyer (FM) test for the lower extremities, Barthel Index (BI), mean walking velocity (v(mean)) over a 6-m distance, and Physiological Cost Index (PCI) were assessed at the entry point and at the end of the treatment. Subjects within the FET and CON groups had comparable baseline outcome measures. In the FET group, we determined significant differences in the mean values of all outcomes between the entry and end points of treatment (p0.05). We also found significant differences in the changes of FM, BI, v(mean) and PCI which occurred during the 4 weeks of treatment between the FET and CON groups (p<0.05). The statistical strength of the clinical study was low (<70%), suggesting the need for a larger, randomized clinical trial.

  4. Using climate response functions in analyzing electricity production variables. A case study from Norway.

    Science.gov (United States)

    Tøfte, Lena S.; Martino, Sara; Mo, Birger

    2016-04-01

    representation of hydropower is included and total hydro power production for each area is calculated, and the production is distributed among all available plants within each area. During simulation, the demand is affected by prices and temperatures. 6 different infrastructure scenarios of wind and power line development are analyzed. The analyses are done by running EMPS calibrated for today's situation for 11*11*8 different combinations of altered weather variables (temperature, precipitation and wind) describing different climate change scenarios, finding the climate response function for every EMPS-variable according the electricity production, such as prices and income, energy balances (supply, consumption and trade), overflow losses, probability of curtailment etc .

  5. Semiclassical Green's function for electron motion in combined Coulomb and electric fields

    Science.gov (United States)

    Ambalampitiya, Harindranath; Fabrikant, Ilya

    2016-05-01

    We are developing an extension of the Green-function approach to the theory of ionization of a multielectron atom in a strong laser field by using the semiclassical Van Vleck-Gutzwiller propagator. For a static field the exact quantum mechanical Green's function can be calculated with an arbitrary accuracy. Therefore, as a first step towards solution of the problem, we apply the semiclassical method to the static field case for the energies above the ionization threshold where all classical trajectories contributing to the Green's function are real. Required trajectories are determined by solving the problem of finding initial velocity and traveling time corresponding to two position points. For the pure electric field case of two trajectories the semiclassical Green's function agrees very well with the exact Green's function. With the inclusion of the Coulomb field, the number of classical trajectories between two points grows rapidly and here we observe that the agreement between the semiclassical and exact Green's functions increases when more trajectories are included in the computation. Supported by the National Science Foundation.

  6. Continual electric field stimulation preserves contractile function of adult ventricular myocytes in primary culture.

    Science.gov (United States)

    Berger, H J; Prasad, S K; Davidoff, A J; Pimental, D; Ellingsen, O; Marsh, J D; Smith, T W; Kelly, R A

    1994-01-01

    To model with greater fidelity the electromechanical function of freshly isolated heart muscle cells in primary culture, we describe a technique for the continual electrical stimulation of adult myocytes at physiological frequencies for several days. A reusable plastic cover was constructed to fit standard, disposable 175-cm2 tissue culture flasks and to hold parallel graphite electrodes along the long axis of each flask, which treated a uniform electric field that resulted in a capture efficiency of ventricular myocytes of 75-80%. Computer-controlled amplifiers were designed to be capable of driving a number of flasks concurrently, each containing up to 4 x 10(6) myocytes, over a range of stimulation frequencies (from 0.1 to 7.0 Hz) with reversal of electrode polarity after each stimulus to prevent the development of pH gradients around each electrode. Unlike quiescent, unstimulated myocytes, the amplitude of contraction, and velocities of shortening and relaxation did not change in myocytes paced at 3-5 Hz for up to 72 h. The maintenance of normal contractile function in paced myocytes required mechanical contraction per se, since paced myocytes that remained quiescent due to the inclusion of 2.5 microM verapamil in the culture medium for 48 h also exhibited a decline in contractility when paced after verapamil removal. Similarly, pacing increased peak calcium current compared with quiescent cells that had not been paced. Thus myocyte contraction at physiological frequencies induced by continual uniform electric field stimulation in short-term primary culture in defining medium maintains some biophysical parameters of myocyte phenotype that are similar to those observed in freshly isolated adult ventricular myocytes.

  7. Study on Electric Double Layer of a Cylindrical Particle with Functional Theoretical Approach

    Institute of Scientific and Technical Information of China (English)

    WANG,Zheng-Wu; LIU,Xue-Min; YU,Hui-Xin; ZHOU,Ming; JIN,Jian

    2007-01-01

    A new method, i.e. the iterative method in functional theory, was introduced to solve analytically the nonlinear Poisson-Boltzmann (PB) equation under general potential ψ condition for the electric double layer of a charged cylindrical colloid particle in a symmetrical electrolyte solution. The iterative solutions of ψ are expressed as functions of the distance from the axis of the particle with solution parameters: the concentration of ions c, the aggregation number of ions in a unit length m, the dielectric constant ε, the system temperature T and so on. The relative errors show that generally only the first and the second iterative solutions can give accuracy higher than 97%. From the second iterative solution the radius and the surface potential of a cylinder have been defined and the corresponding values have been estimated with the solution parameters. Furthermore, the charge density, the activity coefficient of ions and the osmotic coefficient of solvent were also discussed.

  8. Electrical Bistability and Erasable Memory Effect of a Functional Polyimide Film: Synthesis and Investigation of Mechanism

    Science.gov (United States)

    Tian, Guofeng; Jia, Nanfang; Qi, Shengli; Wu, Dezhen

    2015-10-01

    A functional polyimide (PI) film, (hexafluoroisopropylidene)diphthalic anhydride-2-(9 H-carbazol-9-yl)ethyl 3,5-diaminobenzoate (6FDA-DADBC), in which DADBC serves as electron donor and 6FDA as electron acceptor, was synthesized in this work. The PI has electrical bistability and the sandwich device ITO‖6FDA-DADBC-PI‖Au made by using this functional PI as the active layer has nonvolatile memory-storage properties. It can be changed between the insulating state (Off state) and the conducting state (On state) by application of potentials of approximately 0.5 V and -2.5 V, respectively, with an On/Off current ratio of approximately 102, which is suitable for use as flash memory. Mechanisms of the charge transfer occurring in the materials were investigated, and are thoroughly discussed on the basis of molecular simulation. The PI has good thermal stability up to 400°C.

  9. Intelligent algorithm tuning PID method of function electrical stimulation using knee joint angle.

    Science.gov (United States)

    Qiu, Shuang; He, Feng; Tang, Jiabei; Xu, Jiapeng; Zhang, Lixin; Zhao, Xin; Qi, Hongzhi; Zhou, Peng; Cheng, Xiaoman; Wan, Baikun; Ming, Dong

    2014-01-01

    Functional electrical stimulation (FES) could restore motor functions for individuals with spinal cord injury (SCI). By applying electric current pulses, FES system could produce muscle contractions, generate joint torques, and thus, achieve joint movements automatically. Since the muscle system is highly nonlinear and time-varying, feedback control is quite necessary for precision control of the preset action. In the present study, we applied two methods (Proportional Integral Derivative (PID) controller based on Back Propagation (BP) neural network and that based on Genetic Algorithm (GA)), to control the knee joint angle for the FES system, while the traditional Ziegler-Nichols method was used in the control group for comparison. They were tested using a muscle model of the quadriceps. The results showed that intelligent algorithm tuning PID controller displayed superior performance than classic Ziegler-Nichols method with constant parameters. More particularly, PID controller tuned by BP neural network was superior on controlling precision to make the feedback signal track the desired trajectory whose error was less than 1.2°±0.16°, while GA-PID controller, seeking the optimal parameters from multipoint simultaneity, resulted in shortened delay in the response. Both strategies showed promise in application of intelligent algorithm tuning PID methods in FES system.

  10. The effect of Functional Electric Stimulation in stroke patients' motor control - a case report

    Science.gov (United States)

    Pripas, Denise; Rogers Venditi Beas, Allan; Fioramonte, Caroline; Gonsales de Castro, Pedro Claudio; Goroso, Daniel Gustavo; Cecília dos Santos Moreira, Maria

    2011-12-01

    Functional Electric Stimulation (FES) has been studied as a therapeutic resource to reduce spasticity in hemiplegic patients, however there are no studies about the effects of FES in motor control of these patients during functional tasks like balance maintenance. Muscular activation of gastrocnemius medialis and semitendinosus was investigated in both limbs of a hemiparetic patient during self-disturbed quiet stance before and after FES on tibialis anterior, by surface electromyography. The instant of maximum activation peak of GM and ST were calculated immediately after a motor self-disturbance, in order to observe muscular synergy between these two muscles, and possible balance strategies used (ankle or hip strategy). At the preserved limb there occurred distal-proximal synergy (GM followed by ST), expected for small perturbations; however, at spastic limb there was inversion of this synergy (proximal-distal) after FES. It is possible that intervention of electricity had inhibited synergical pathways due to antidromic effect, making it difficult to use ankle strategy in the spastic limb.

  11. Molecular Monolayers for Electrical Passivation and Functionalization of Silicon-Based Solar Energy Devices.

    Science.gov (United States)

    Veerbeek, Janneke; Firet, Nienke J; Vijselaar, Wouter; Elbersen, Rick; Gardeniers, Han; Huskens, Jurriaan

    2017-01-11

    Silicon-based solar fuel devices require passivation for optimal performance yet at the same time need functionalization with (photo)catalysts for efficient solar fuel production. Here, we use molecular monolayers to enable electrical passivation and simultaneous functionalization of silicon-based solar cells. Organic monolayers were coupled to silicon surfaces by hydrosilylation in order to avoid an insulating silicon oxide layer at the surface. Monolayers of 1-tetradecyne were shown to passivate silicon micropillar-based solar cells with radial junctions, by which the efficiency increased from 8.7% to 9.9% for n(+)/p junctions and from 7.8% to 8.8% for p(+)/n junctions. This electrical passivation of the surface, most likely by removal of dangling bonds, is reflected in a higher shunt resistance in the J-V measurements. Monolayers of 1,8-nonadiyne were still reactive for click chemistry with a model catalyst, thus enabling simultaneous passivation and future catalyst coupling.

  12. Effectiveness of neuromuscular electrical stimulation in the functional knee rehabilitation in soldiers

    Directory of Open Access Journals (Sweden)

    R. Castillo-Lozano

    2015-12-01

    Full Text Available Background: The versatility of military physical therapist practice enables them not only to diagnose knee injuries but also to provide a wide range of definitive care and rehabilitation, reducing the need for costly evacuation. The aim this study was to evaluate the effectiveness of interventions by Neuromuscular Electrical Stimulation (NMES in the functional knee rehabilitation in soldiers and describe the main predictors and determinants in each intervention. Methods: A systematic search of the literature about NMES in physiotherapy was performed using the following electronic databases: Web of Science, PubMed, Cochrane, Physiotherapy Evidence Database (PEDro and CINAHL. The search strategy was: "neuromuscular electrical stimulation" and "physical therapy" and "strengthening" and "knee". Inclusion criteria were: original articles published and peer reviewed between 2004-2015, focusing on physiotherapy interventions by NMES on subjects older than 18 years. A total resulting from 46 studies was included in the study. Results: The results show the evidence on the effectiveness of NMES therapeutic/preventive purposes in the muscular system; and the importance of physical therapy in the army. Conclusion: As a method of functional knee rehabilitation, NMES proves effective in achieving the therapeutic/preventive objectives in soldiers. Level of Evidence: II. Systematic review of randomized clinical trials with homogeneity.

  13. Microsoft Kinect-Based Artificial Perception System for Control of Functional Electrical Stimulation Assisted Grasping

    Directory of Open Access Journals (Sweden)

    Matija Štrbac

    2014-01-01

    Full Text Available We present a computer vision algorithm that incorporates a heuristic model which mimics a biological control system for the estimation of control signals used in functional electrical stimulation (FES assisted grasping. The developed processing software acquires the data from Microsoft Kinect camera and implements real-time hand tracking and object analysis. This information can be used to identify temporal synchrony and spatial synergies modalities for FES control. Therefore, the algorithm acts as artificial perception which mimics human visual perception by identifying the position and shape of the object with respect to the position of the hand in real time during the planning phase of the grasp. This artificial perception used within the heuristically developed model allows selection of the appropriate grasp and prehension. The experiments demonstrate that correct grasp modality was selected in more than 90% of tested scenarios/objects. The system is portable, and the components are low in cost and robust; hence, it can be used for the FES in clinical or even home environment. The main application of the system is envisioned for functional electrical therapy, that is, intensive exercise assisted with FES.

  14. Classical and adaptive control of ex vivo skeletal muscle contractions using Functional Electrical Stimulation (FES)

    Science.gov (United States)

    Shoemaker, Adam; Grange, Robert W.; Abaid, Nicole; Leonessa, Alexander

    2017-01-01

    Functional Electrical Stimulation is a promising approach to treat patients by stimulating the peripheral nerves and their corresponding motor neurons using electrical current. This technique helps maintain muscle mass and promote blood flow in the absence of a functioning nervous system. The goal of this work is to control muscle contractions from FES via three different algorithms and assess the most appropriate controller providing effective stimulation of the muscle. An open-loop system and a closed-loop system with three types of model-free feedback controllers were assessed for tracking control of skeletal muscle contractions: a Proportional-Integral (PI) controller, a Model Reference Adaptive Control algorithm, and an Adaptive Augmented PI system. Furthermore, a mathematical model of a muscle-mass-spring system was implemented in simulation to test the open-loop case and closed-loop controllers. These simulations were carried out and then validated through experiments ex vivo. The experiments included muscle contractions following four distinct trajectories: a step, sine, ramp, and square wave. Overall, the closed-loop controllers followed the stimulation trajectories set for all the simulated and tested muscles. When comparing the experimental outcomes of each controller, we concluded that the Adaptive Augmented PI algorithm provided the best closed-loop performance for speed of convergence and disturbance rejection. PMID:28273101

  15. Feasibility of Functional Electrical Stimulation-Assisted Neurorehabilitation following Stroke in India: A Case Series

    Directory of Open Access Journals (Sweden)

    Bhawna Khattar

    2012-01-01

    Full Text Available Functional Electrical Stimulation (FES facilitates ambulatory function after paralysis by electrically activating the muscles of the lower extremities. The Odstock Dropped Foot Stimulator (ODFS, Odstock, UK called ODFS Pace, was used for heel-switch triggered FES-assisted walking. The ODFS is recommended as an intervention for neurologically impaired gait in the Royal College of Physicians (UK Clinical Guidelines on Stroke. Based on the guidelines by the National Institute of Clinical Excellence (NICE, UK, we started first clinical study in India on ODFS Pace as an orthotic intervention for daily use. In this preliminary study, we also investigated improvement in volitional walking following 6 sessions (3 times per week, for 2 weeks of 30 minutes of FES-assisted treadmill walking on 7 chronic (>6 months after stroke stroke survivors. We found that short-duration, moderately intensive FES-assisted gait therapy improved volitional gait in 3 out of 7 stroke survivors suffering from foot drop. Even in absence of improvement in volitional walking, there were no adverse effects and the subjects found heel-switch triggered FES-assisted walking mostly “easy” (6 out of 7. Therefore FES is promising as an orthotic intervention for daily use; however, tailoring the intensity and/or frequency based on patient's ability may make it viable as a therapeutic intervention.

  16. Microsoft kinect-based artificial perception system for control of functional electrical stimulation assisted grasping.

    Science.gov (United States)

    Strbac, Matija; Kočović, Slobodan; Marković, Marko; Popović, Dejan B

    2014-01-01

    We present a computer vision algorithm that incorporates a heuristic model which mimics a biological control system for the estimation of control signals used in functional electrical stimulation (FES) assisted grasping. The developed processing software acquires the data from Microsoft Kinect camera and implements real-time hand tracking and object analysis. This information can be used to identify temporal synchrony and spatial synergies modalities for FES control. Therefore, the algorithm acts as artificial perception which mimics human visual perception by identifying the position and shape of the object with respect to the position of the hand in real time during the planning phase of the grasp. This artificial perception used within the heuristically developed model allows selection of the appropriate grasp and prehension. The experiments demonstrate that correct grasp modality was selected in more than 90% of tested scenarios/objects. The system is portable, and the components are low in cost and robust; hence, it can be used for the FES in clinical or even home environment. The main application of the system is envisioned for functional electrical therapy, that is, intensive exercise assisted with FES.

  17. Feasibility of a Hybrid Brain-Computer Interface for Advanced Functional Electrical Therapy

    Directory of Open Access Journals (Sweden)

    Andrej M. Savić

    2014-01-01

    Full Text Available We present a feasibility study of a novel hybrid brain-computer interface (BCI system for advanced functional electrical therapy (FET of grasp. FET procedure is improved with both automated stimulation pattern selection and stimulation triggering. The proposed hybrid BCI comprises the two BCI control signals: steady-state visual evoked potentials (SSVEP and event-related desynchronization (ERD. The sequence of the two stages, SSVEP-BCI and ERD-BCI, runs in a closed-loop architecture. The first stage, SSVEP-BCI, acts as a selector of electrical stimulation pattern that corresponds to one of the three basic types of grasp: palmar, lateral, or precision. In the second stage, ERD-BCI operates as a brain switch which activates the stimulation pattern selected in the previous stage. The system was tested in 6 healthy subjects who were all able to control the device with accuracy in a range of 0.64–0.96. The results provided the reference data needed for the planned clinical study. This novel BCI may promote further restoration of the impaired motor function by closing the loop between the “will to move” and contingent temporally synchronized sensory feedback.

  18. Functional electrical stimulation of intrinsic laryngeal muscles under varying loads in exercising horses.

    Directory of Open Access Journals (Sweden)

    Jon Cheetham

    Full Text Available Bilateral vocal fold paralysis (BVCP is a life threatening condition and appears to be a good candidate for therapy using functional electrical stimulation (FES. Developing a working FES system has been technically difficult due to the inaccessible location and small size of the sole arytenoid abductor, the posterior cricoarytenoid (PCA muscle. A naturally-occurring disease in horses shares many functional and etiological features with BVCP. In this study, the feasibility of FES for equine vocal fold paralysis was explored by testing arytenoid abduction evoked by electrical stimulation of the PCA muscle. Rheobase and chronaxie were determined for innervated PCA muscle. We then tested the hypothesis that direct muscle stimulation can maintain airway patency during strenuous exercise in horses with induced transient conduction block of the laryngeal motor nerve. Six adult horses were instrumented with a single bipolar intra-muscular electrode in the left PCA muscle. Rheobase and chronaxie were within the normal range for innervated muscle at 0.55±0.38 v and 0.38±0.19 ms respectively. Intramuscular stimulation of the PCA muscle significantly improved arytenoid abduction at all levels of exercise intensity and there was no significant difference between the level of abduction achieved with stimulation and control values under moderate loads. The equine larynx may provide a useful model for the study of bilateral fold paralysis.

  19. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function.

    Science.gov (United States)

    Carmel, Jason B; Martin, John H

    2014-01-01

    The corticospinal system-with its direct spinal pathway, the corticospinal tract (CST) - is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that 10 days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay.

  20. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    Directory of Open Access Journals (Sweden)

    Jason B Carmel

    2014-06-01

    Full Text Available The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST—is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that ten days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay.

  1. Functional electrical stimulation-facilitated proliferation and regeneration of neural precursor cells in the brains of rats with cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Yun Xiang; Huihua Liu; Tiebin Yan; Zhiqiang Zhuang; Dongmei Jin; Yuan Peng

    2014-01-01

    Previous studies have shown that proliferation of endogenous neural precursor cells cannot alone compensate for the damage to neurons and axons. From the perspective of neural plastici-ty, we observed the effects of functional electrical stimulation treatment on endogenous neural precursor cell proliferation and expression of basic fibroblast growth factor and epidermal growth factor in the rat brain on the infarct side. Functional electrical stimulation was performed in rat models of acute middle cerebral artery occlusion. Simultaneously, we set up a placebo stimulation group and a sham-operated group. Immunohistochemical staining showed that, at 7 and 14 days, compared with the placebo group, the numbers of nestin (a neural precursor cell marker)-positive cells in the subgranular zone and subventricular zone were increased in the functional electrical stimulation treatment group. Western blot assays and reverse-transcription PCR showed that total protein levels and gene expression of epidermal growth factor and basic ifbroblast growth factor were also upregulated on the infarct side. Prehensile traction test results showed that, at 14 days, prehension function of rats in the functional electrical stimulation group was signiifcantly better than in the placebo group. These results suggest that functional electrical stimulation can promote endogenous neural precursor cell proliferation in the brains of acute cerebral infarction rats, enhance expression of basic fibroblast growth factor and epidermal growth factor, and improve the motor function of rats.

  2. Electrical conductivity and thermal properties of functionalized carbon nanotubes/polyurethane composites

    Directory of Open Access Journals (Sweden)

    Aline M. F. Lima

    2012-01-01

    Full Text Available Multi-walled carbon nanotubes (MWCNTs functionalized with amine and carboxyl groups were used to prepare polyurethane/MWCNT nanocomposites in two distinct concentrations: a lower value of 1 mass% (spray coating and a higher one of ~50 mass% (buckypaper based. The MWCNT-NH2 sample contained only 0.5 mass% of amine groups, whereas MWCNT-COOH contained 5 mass% of carboxyl groups. The MWCNT functionalized with low amine group content showed improved thermal properties when compared to neat thermoplastic polyurethane (TPU and MWCNT-COOH based nanocomposites. The electrical conductivity of the polyurethane elastomer was greatly increased from 10-12 to ~10-5 S cm-1in the 1 mass% nanotube composite and to 7 S cm-1for the MWCNT-NH2 buckypaper-based nanocomposite. Furthermore, the relative high content of functional groups in the MWCNT-COOH sample, which disrupt the sp²structure in the nanotube walls, led to inferior properties; for instance the conductivity of the buckypaper based composite is one order of magnitude lower when using MWCNT-COOH in comparison with the MWCNT-NH2. These results show the range of property design possibilities available with the elastomeric polyurethane nanocomposite by tailoring the functional group content and the carbon nanotube load.

  3. Dual-channel functional electrical stimulation improvements in speed-based gait classifications

    Directory of Open Access Journals (Sweden)

    Springer S

    2013-02-01

    Full Text Available Shmuel Springer,1,2 Yocheved Laufer,1 Meni Becher,1,2 Jean-Jacques Vatine3,41Department of Physical Therapy, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, 2Clinical Department, Bioness Neuromodulation, Ra'anana, 3Outpatient and Research Division, Reuth Medical Center, Tel Aviv, 4Department of Rehabilitation Medicine, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, IsraelBackground: Functional electrical stimulation (FES is becoming an accepted treatment method for enhancing gait performance in patients who present with gait difficulties resulting from hemiparesis. The purpose of this study was to test whether individuals with hemiparesis who have varied gait speeds, which place them in different functional categories, benefit to the same extent from the application of FES.Methods: Thirty-six subjects with chronic hemiparesis demonstrating foot-drop and deficits in knee and/or hip control were fitted with a dual-channel FES system activating the dorsiflexors and hamstring muscles. Gait was assessed during a 2-minute walk test with and without stimulation. A second assessment was conducted after 6 weeks of daily use. Analysis was performed with the subjects stratified into three functional ambulation classes according to their initial gait categories.Results: The dual-channel FES improved the gait velocity of all three subgroups. No minimal gait velocity was required in order to gain benefits from FES. For example, subjects with limited household ambulation capabilities improved their gait speed by 63.3% (from 0.30 ± 0.09 m/sec to 0.49 ± 0.20 m/sec; P < 0.01, while subjects with functional community ambulation capabilities improved their gait speed by 25.5% (from 0.90 ± 0.11 m/sec to 1.13 ± 0.22 m/sec; P < 0.01.Conclusion: Dual-channel FES positively affects gait velocity in patients with chronic hemiparesis, regardless of their initial gait velocity. Furthermore, gait velocity gains may be large enough

  4. Effect of Raykeen holmium laser electric resection and conventional electric resection on malignant degree and immune function of non-invasive bladder cancer

    Institute of Scientific and Technical Information of China (English)

    Liang-Suo Zhang

    2016-01-01

    Objective:To analyze the effect of Raykeen holmium laser electric resection and conventional electric resection on the malignant degree and immune function of non-invasive bladder cancer. Methods:A total of 96 cases of patients with non-invasive bladder cancer were included for study and divided into observation group 46 cases who received Raykeen holmium laser electric resection treatment and control group 50 cases who received conventional electric resection treatment. Differences in postoperative illness-related indexes, serum adhesion molecule levels, urinary sediment miRNA and immune function-related indexes were compared between two groups.Results:Serum DKK-3 and Endostatin values of observation group after treatment were higher than those of control group while CIP2A, DKK-1 and sFasL values were lower than those of control group; serum CD44v6, E-cadherin and hepaCAM values of observation group after treatment were higher than those of control group while EpCAM, sVCAM-1 and sICAM-1 values were lower than those of control group; urinary sediment miR-129, miR-125b, miR-720, miR-191 and miR-107 expression levels of observation group after treatment were lower than those of control group; serum IgG, IgA, IgM, C3, C4, CD4+ and CD4+/CD8+ values of observation group after treatment were higher than those of control group while CD8+ value was lower than that of control group.Conclusions:Raykeen holmium laser electric resection treatment of patients with non-invasive bladder cancer can effectively reduce the malignant degree of tumor and improve body’s immune function, and it has positive clinical significance.

  5. Electroencephalography(EEG)-based instinctive brain-control of a quadruped locomotion robot.

    Science.gov (United States)

    Jia, Wenchuan; Huang, Dandan; Luo, Xin; Pu, Huayan; Chen, Xuedong; Bai, Ou

    2012-01-01

    Artificial intelligence and bionic control have been applied in electroencephalography (EEG)-based robot system, to execute complex brain-control task. Nevertheless, due to technical limitations of the EEG decoding, the brain-computer interface (BCI) protocol is often complex, and the mapping between the EEG signal and the practical instructions lack of logic associated, which restrict the user's actual use. This paper presents a strategy that can be used to control a quadruped locomotion robot by user's instinctive action, based on five kinds of movement related neurophysiological signal. In actual use, the user drives or imagines the limbs/wrists action to generate EEG signal to adjust the real movement of the robot according to his/her own motor reflex of the robot locomotion. This method is easy for real use, as the user generates the brain-control signal through the instinctive reaction. By adopting the behavioral control of learning and evolution based on the proposed strategy, complex movement task may be realized by instinctive brain-control.

  6. Trade-off between the Mechanical Strength and Microwave Electrical Properties of Functionalized and Irradiated Carbon Nanotube Sheets.

    Science.gov (United States)

    Williams, Tiffany S; Orloff, Nathan D; Baker, James S; Miller, Sandi G; Natarajan, Bharath; Obrzut, Jan; McCorkle, Linda S; Lebron-Colón, Marisabel; Gaier, James; Meador, Michael A; Liddle, J Alexander

    2016-04-13

    Carbon nanotube (CNT) sheets represent a novel implementation of CNTs that enable the tailoring of electrical and mechanical properties for applications in the automotive and aerospace industries. Small molecule functionalization and postprocessing techniques, such as irradiation with high-energy particles, are methods that can enhance the mechanical properties of CNTs. However, the effect that these modifications have on the electrical conduction mechanisms has not been extensively explored. By characterizing the mechanical and electrical properties of multiwalled carbon nanotube (MWCNT) sheets with different functional groups and irradiation doses, we can expand our insights into the extent of the trade-off that exists between mechanical strength and electrical conductivity for commercially available CNT sheets. Such insights allow for the optimization of design pathways for engineering applications that require a balance of material property enhancements.

  7. Effects of motor imagery combined with functional electrical stimulation on upper limb motor function of patients with acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Shou-feng LIU

    2015-03-01

    Full Text Available Objective To explore the effects of motor imagery (MI combined with the third generation functional electrical stimulation (FES on upper limb motor function in acute ischemic stroke patients with hemiplegia.  Methods Forty acute ischemic stroke patients, within 48 h of onset, were randomly divided into FES group (N = 20 and combination group (FES combined with motor imagery, N = 20. All patients received basic routine rehabilitation training, for example, good limb positioning, accepting braces, balance training and training in the activities of daily living (ADL. FES group received the third generation FES therapy and the combination group also received motor imagery for 2 weeks. All of the patients were assessed with Fugl-Meyer Assessment (FMA, Action Research Arm Test (ARAT and active range of motion (AROM of wrist dorsiflexion before and after 2 weeks of treatment.  Results After 2 weeks of treatment, the 2 groups had significantly higher FMA score, ARAT score and AROM of wrist dorsiflexion than that in pre-treatment (P = 0.000, for all. Besides, the FMA score (t = - 2.528, P = 0.016, ARAT score (t = - 2.562, P = 0.014 and AROM of wrist dorsiflexion (t = - 2.469, P = 0.018 in the combination group were significantly higher than that in the FES group. There were interactions of treatment methods with observation time points (P < 0.05, for all.  Conclusions Motor imagery combined with the third generation FES can effectively promote the recovery of upper limb motor function and motion range of wrist dorsiflexion in patients with acute ischemic stroke. DOI: 10.3969/j.issn.1672-6731.2015.03.008

  8. Chronic exposure to 60-Hz electric fields: effects on pineal function in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B.W.; Anderson, L.E.; Hilton, D.I.; Philips, R.D.

    1980-01-01

    As a component of studies to search for effects of 60-Hz electric field exposure on mammalian endocrine function, concentrations of melatonin, 5-methoxytryptophol, and serotonin-N-acetyl transferase activity were measured in the pineal glands of rats exposed or sham-exposed at 65 kV/m for 30 days.In two replicate experiments there were statistically significant differences between exposed and control rats in that the normal nocturnal increase in pineal melatonin content was depressed in the exposed animals. Concentrations of 5-methoxytryptophol were increased in the pineal glands of the exposed groups when compared to sham-exposed controls. An alteration was also observed in serotonin-N-acetyl transferase activity, with lower levels measured in pineal glands from exposed animals.

  9. Electrode Wear Prediction in Milling Electrical Discharge Machining Based on Radial Basis Function Neural Network

    Institute of Scientific and Technical Information of China (English)

    HUANG He; BAI Ji-cheng; LU Ze-sheng; GUO Yong-feng

    2009-01-01

    Milling electrical discharge machining (EDM) enables the machining of complex cavities using cylindrical or tubular electrodes. To ensure acceptable machining accuracy the process requires some methods of compensating for electrode wear. Due to the complexity and random nature of the process, existing methods of compensating for such wear usually involve off-line prediction. This paper discusses an innovative model of electrode wear prediction for milling EDM based upon a radial basis function (RBF) network. Data gained from an orthogonal experiment were used to provide training samples for the RBF network. The model established was used to forecast the electrode wear, making it possible to calculate the real-time tool wear in the milling EDM process and, to lay the foundations for dynamic compensation of the electrode wear on-line. This paper demonstrates that by using this model prediction errors can be controlled within 8%.

  10. Study on the Radius of an Electrical Spherical Micelle:Functional Theoretical Approach

    Institute of Scientific and Technical Information of China (English)

    WANG,Zheng-Wu(王正武); HUANG,Dong-Yang(黄东阳); YI,Xi-Zhang(易希璋); LI,Gan-Zuo(李干佐)

    2004-01-01

    For the purpose of eliminating restriction,the Poisson-Boltzmann(PB)equation,which represents the potential of the electrical double layer of spherical micelles,can be solved analytically only under the lower potential condition,a kind of iterative method in functional analysis theory has been used.The radius of the spherical particle can be obtained from the diagram of the second iterative solution of the potential versus the distance from the center of the particle.The influences of the concentration of the ions,the charge number of ions,the aggregation number of the particle,the dielectric constant of solvent and the temperature of system on the radius also have been studied.

  11. Functional asymmetry between the left and right human fusiform gyrus explored through electrical brain stimulation.

    Science.gov (United States)

    Rangarajan, Vinitha; Parvizi, Josef

    2016-03-01

    The ventral temporal cortex (VTC) contains several areas with selective responses to words, numbers, faces, and objects as demonstrated by numerous human and primate imaging and electrophysiological studies. Our recent work using electrocorticography (ECoG) confirmed the presence of face-selective neuronal populations in the human fusiform gyrus (FG) in patients implanted with intracranial electrodes in either the left or right hemisphere. Electrical brain stimulation (EBS) disrupted the conscious perception of faces only when it was delivered in the right, but not left, FG. In contrast to our previous findings, here we report both negative and positive EBS effects in right and left FG, respectively. The presence of right hemisphere language dominance in the first, and strong left-handedness and poor language processing performance in the second case, provide indirect clues about the functional architecture of the human VTC in relation to hemispheric asymmetries in language processing and handedness.

  12. Impact of Functional Electrical Stimulation of Lower Limbs during Sitting Pivot Transfer Motion for Paraplegic People

    Directory of Open Access Journals (Sweden)

    Jovana Jovic

    2013-01-01

    Full Text Available Individuals with Spinal Cord Injury (SCI, perform Sitting Pivot Transfer (SPT motion around fifteen times a day using upper extremities. It can lead to upper limbs pain and often shoulder complications. In this paper, we investigate the influence of Functional Electrical Stimulation (FES on SPT motion of a paraplegic person. First, we proposed to develop a dynamic optimization method in order to predict SPT motion of an able‐bodied subject. This approach has been validated by comparing the computed SPT trajectories with the ones measured during the experiment with an able‐bodied subject. Then, we used the optimization tool to analyze the influence of FES on the SPT maneuver of paraplegic persons. Our results suggest that FES can decrease arm participation during the transfer motion of a paraplegic person.

  13. Neurotherapeutic and neuroprosthetic effects of implanted functional electrical stimulation for ambulation after incomplete spinal cord injury.

    Science.gov (United States)

    Bailey, Stephanie Nogan; Hardin, Elizabeth C; Kobetic, Rudi; Boggs, Lisa M; Pinault, Gilles; Triolo, Ronald J

    2010-01-01

    The purpose of this single-subject study was to determine the neurotherapeutic and neuroprosthetic effects of an implanted functional electrical stimulation (FES) system designed to facilitate walking in an individual with a longstanding motor and sensory incomplete spinal cord injury. An implanted pulse generator and eight intramuscular stimulating electrodes were installed unilaterally, activating weak or paralyzed hip flexors, hip and knee extensors, and ankle dorsiflexors during 36 sessions of gait training with FES. The neurotherapeutic effects were assessed by a comparison of pre- and posttraining volitional walking. The neuroprosthetic effects were assessed by a comparison of posttraining volitional and FES-assisted walking. Treatment resulted in significant (p ambulation to limited community ambulation. Additionally, the subject could perform multiple walks per day when using FES-assisted gait, which was impossible with volitional effort alone.

  14. Using CPE Function to Size Capacitor Storage for Electric Vehicles and Quantifying Battery Degradation during Different Driving Cycles

    OpenAIRE

    Cong Zhang; Haitao Min; Yuanbin Yu; Dai Wang; Justin Luke; Daniel Opila; Samveg Saxena

    2016-01-01

    Range anxiety and battery cycle life are two major factors which restrict the development of electric vehicles. Battery degradation can be reduced by adding supercapacitors to create a Hybrid Energy Storage System. This paper proposes a systematic approach to configure the hybrid energy storage system and quantifies the battery degradation for electric vehicles when using supercapacitors. A continuous power-energy function is proposed to establish supercapacitor size based on national househo...

  15. Functional improvement and maturation of rat and human engineered heart tissue by chronic electrical stimulation.

    Science.gov (United States)

    Hirt, Marc N; Boeddinghaus, Jasper; Mitchell, Alice; Schaaf, Sebastian; Börnchen, Christian; Müller, Christian; Schulz, Herbert; Hubner, Norbert; Stenzig, Justus; Stoehr, Andrea; Neuber, Christiane; Eder, Alexandra; Luther, Pradeep K; Hansen, Arne; Eschenhagen, Thomas

    2014-09-01

    Spontaneously beating engineered heart tissue (EHT) represents an advanced in vitro model for drug testing and disease modeling, but cardiomyocytes in EHTs are less mature and generate lower forces than in the adult heart. We devised a novel pacing system integrated in a setup for videooptical recording of EHT contractile function over time and investigated whether sustained electrical field stimulation improved EHT properties. EHTs were generated from neonatal rat heart cells (rEHT, n=96) or human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hEHT, n=19). Pacing with biphasic pulses was initiated on day 4 of culture. REHT continuously paced for 16-18 days at 0.5Hz developed 2.2× higher forces than nonstimulated rEHT. This was reflected by higher cardiomyocyte density in the center of EHTs, increased connexin-43 abundance as investigated by two-photon microscopy and remarkably improved sarcomere ultrastructure including regular M-bands. Further signs of tissue maturation include a rightward shift (to more physiological values) of the Ca(2+)-response curve, increased force response to isoprenaline and decreased spontaneous beating activity. Human EHTs stimulated at 2Hz in the first week and 1.5Hz thereafter developed 1.5× higher forces than nonstimulated hEHT on day 14, an ameliorated muscular network of longitudinally oriented cardiomyocytes and a higher cytoplasm-to-nucleus ratio. Taken together, continuous pacing improved structural and functional properties of rEHTs and hEHTs to an unprecedented level. Electrical stimulation appears to be an important step toward the generation of fully mature EHT.

  16. Gastric motility functional study based on electrical bioimpedance measurements and simultaneous electrogastrography

    Institute of Scientific and Technical Information of China (English)

    Zhang-yong LI; Chao-shi REN; Shu ZHAO; Hong SHA; Juan DENG

    2011-01-01

    For some time now,the research on gastric motility and function has fallen behind in the amount of research on gastric endocrine,exocrine secretion,and gastric morphology.In this paper,a noninvasive method to study gastric motility was developed,taking bioimpedance measurements over the gastric area simultaneously with the electrogastrography (EGG).This is based on the concept of observing and analyzing simultaneously the intrinsic electrical gastric activity (basic electric rhythm) and the mechanical gastric activity.Additionally,preliminary clinical studies of healthy subjects and subjects with functional dyspepsia (FD) and gastritis were carried out.The impedance gastric motility (IGM) measurements of the healthy and FD subjects were compared,along with the studies of the FD subjects before treatment and after one week and three weeks of treatment.We also compared IGM measurements of healthy subjects and subjects with erosive gastritis,along with the studies of the subjects with erosive gastritis before treatment and after one week of treatment.Results show that FD subjects have poor gastric motility (P<0.01).After a week of treatment,the gastric motility of FD subjects was not yet improved although the EGG had returned to normal by this time.By three weeks of treatment,the regular IGM rhythm returned in FD subjects.There was a significant difference of IGM parameters between the gastritis and healthy subjects (P<0.05).The EGG rhythm of the gastritis subjects returned to normal at one week post-treatment,while IGM parameters showed a trend to improvement (P>0.05),These results suggest the possibility of clinic application of the proposed method.

  17. Non-linear analysis of body responses to functional electrical stimulation on hemiplegic subjects.

    Science.gov (United States)

    Yu, W W; Acharya, U R; Lim, T C; Low, H W

    2009-08-01

    Functional electrical stimulation (FES) is a method of applying low-level electrical currents to restore or improve body functions lost through nervous system impairment. FES is applied to peripheral nerves that control specific muscles or muscle groups. Application of advanced signal computing techniques to the medical field has helped to achieve practical solutions to the health care problems accurately. The physiological signals are essentially non-stationary and may contain indicators of current disease, or even warnings about impending diseases. These indicators may be present at all times or may occur at random on the timescale. However, to study and pinpoint these subtle changes in the voluminous data collected over several hours is tedious. These signals, e.g. walking-related accelerometer signals, are not simply linear and involve non-linear contributions. Hence, non-linear signal-processing methods may be useful to extract the hidden complexities of the signal and to aid physicians in their diagnosis. In this work, a young female subject with major neuromuscular dysfunction of the left lower limb, which resulted in an asymmetric hemiplegic gait, participated in a series of FES-assisted walking experiments. Two three-axis accelerometers were attached to her left and right ankles and their corresponding signals were recorded during FES-assisted walking. The accelerometer signals were studied in three directions using the Hurst exponent H, the fractal dimension (FD), the phase space plot, and recurrence plots (RPs). The results showed that the H and FD values increase with increasing FES, indicating more synchronized variability due to FES for the left leg (paralysed leg). However, the variation in the normal right leg is more chaotic on FES.

  18. Cardiorespiratory, metabolic, and biomechanical responses during functional electrical stimulation leg exercise: health and fitness benefits.

    Science.gov (United States)

    Davis, Glen M; Hamzaid, Nur A; Fornusek, Ché

    2008-08-01

    Functional electrical stimulation (FES)-induced leg exercise offers the potential for individuals with lower-limb paralysis to otherwise gain some benefits conferred by leg exercise. Although its original intent is to reactivate the leg muscles to produce functional upright mobility, as a rehabilitation therapy, FES-evoked exercise increases the whole-body metabolism of individuals with spinal cord injury (SCI) so that they may gain general and localized health and fitness benefits. The physiological and psychosocial responses during FES-evoked cycling, standing, rowing, leg extension, or stepping have been extensively explored for over 20 years. Some of the advantages of such exercise include augmented cardiorespiratory fitness, promotion of leg blood circulation, increased activity of specific metabolic enzymes or hormones, greater muscle volume and fiber size, enhanced functional exercise capacity such as strength and endurance, and altered bone mineral density. Positive psychosocial adaptations have also been reported among SCI individuals who undergo FES exercise. This article presents a position review of the available literature on the effects of FES-evoked exercise since the earliest date until 2007, to warrant a conclusion about the current status and potential of FES-evoked exercise for paralyzed people.

  19. Functional Magnetic Resonance Imaging of Electrical and Optogenetic Deep Brain Stimulation at the Rat Nucleus Accumbens

    Science.gov (United States)

    Albaugh, Daniel L.; Salzwedel, Andrew; van den Berge, Nathalie; Gao, Wei; Stuber, Garret D.; Shih, Yen-Yu Ian

    2016-09-01

    Deep brain stimulation of the nucleus accumbens (NAc-DBS) is an emerging therapy for diverse, refractory neuropsychiatric diseases. Although DBS therapy is broadly hypothesized to work through large-scale neural modulation, little is known regarding the neural circuits and networks affected by NAc-DBS. Using a healthy, sedated rat model of NAc-DBS, we employed both evoked- and functional connectivity (fc) MRI to examine the functional circuit and network changes achieved by electrical NAc stimulation. Optogenetic-fMRI experiments were also undertaken to evaluate the circuit modulation profile achieved by selective stimulation of NAc neurons. NAc-DBS directly modulated neural activity within prefrontal cortex and a large number of subcortical limbic areas (e.g., amygdala, lateral hypothalamus), and influenced functional connectivity among sensorimotor, executive, and limbic networks. The pattern and extent of circuit modulation measured by evoked-fMRI was relatively insensitive to DBS frequency. Optogenetic stimulation of NAc cell bodies induced a positive fMRI signal in the NAc, but no other detectable downstream responses, indicating that therapeutic NAc-DBS might exert its effect through antidromic stimulation. Our study provides a comprehensive mapping of circuit and network-level neuromodulation by NAc-DBS, which should facilitate our developing understanding of its therapeutic mechanisms of action.

  20. Functional Magnetic Resonance Imaging of Electrical and Optogenetic Deep Brain Stimulation at the Rat Nucleus Accumbens

    Science.gov (United States)

    Albaugh, Daniel L.; Salzwedel, Andrew; Van Den Berge, Nathalie; Gao, Wei; Stuber, Garret D.; Shih, Yen-Yu Ian

    2016-01-01

    Deep brain stimulation of the nucleus accumbens (NAc-DBS) is an emerging therapy for diverse, refractory neuropsychiatric diseases. Although DBS therapy is broadly hypothesized to work through large-scale neural modulation, little is known regarding the neural circuits and networks affected by NAc-DBS. Using a healthy, sedated rat model of NAc-DBS, we employed both evoked- and functional connectivity (fc) MRI to examine the functional circuit and network changes achieved by electrical NAc stimulation. Optogenetic-fMRI experiments were also undertaken to evaluate the circuit modulation profile achieved by selective stimulation of NAc neurons. NAc-DBS directly modulated neural activity within prefrontal cortex and a large number of subcortical limbic areas (e.g., amygdala, lateral hypothalamus), and influenced functional connectivity among sensorimotor, executive, and limbic networks. The pattern and extent of circuit modulation measured by evoked-fMRI was relatively insensitive to DBS frequency. Optogenetic stimulation of NAc cell bodies induced a positive fMRI signal in the NAc, but no other detectable downstream responses, indicating that therapeutic NAc-DBS might exert its effect through antidromic stimulation. Our study provides a comprehensive mapping of circuit and network-level neuromodulation by NAc-DBS, which should facilitate our developing understanding of its therapeutic mechanisms of action. PMID:27601003

  1. Do the Effects of Transcutaneous Electrical Nerve Stimulation on Knee Osteoarthritis Pain and Function Last?

    Science.gov (United States)

    Cherian, Jeffrey Jai; Harrison, Paige E; Benjamin, Samantha A; Bhave, Anil; Harwin, Steven F; Mont, Michael A

    2016-08-01

    Transcutaneous electrical nerve stimulation (TENS) has been shown to decrease pain associated with knee osteoarthritis, which potentially leads to better function, improved quality of life, and postpones the need for surgical intervention. The purpose of this study was to perform a 1-year follow-up of a previous prospective group of patients with knee osteoarthritis, randomized to TENS or standard of care, who were asked to rate their changes in: (1) patient pain perception; (2) subjective medication use; (3) subjective functional abilities; (4) quality of life; (5) device use; and (6) conversion to TKA. A population of 70 patients were randomized to receive either a TENS device or a standard conservative therapy regimen. Patients were evaluated based on various subjective outcomes at minimum 1-year (mean, 19 months) follow-up. The TENS cohort had lower visual analog pain scores compared with the matching cohort. Subjective functional outcomes, as well as functional and activity scores, were also greater in the TENS cohort. Patients in TENS cohort showed significant improvements in their subjective and functional outcomes as compared with their initial status, while the control group did not show significant change. A majority of the TENS patients were able to reduce the amount of pain medications. Additionally, a large portion of the patients assigned to the TENS group continue to use the device, after completion of the trial. This study demonstrated the benefit of TENS for improving subjective outcomes in patients with pain due to knee osteoarthritis, compared with standard conservative treatments. The results of the study suggest that TENS is a safe and effective adjunct as part of the spectrum of current nonoperative treatment methods for knee osteoarthritis.

  2. The electricity exchange. On the organisation and latent functions of electricity exchange trading as seen from the viewpoint of market sociology; Die Stromboerse. Ueber Form und latente Funktionen des boerslichen Stromhandels aus marktsoziologischer Sicht

    Energy Technology Data Exchange (ETDEWEB)

    Giacovelli, Sebastian

    2014-07-01

    Electricity exchange trading in Germany has existed since the year 2000. Since this time, the Leipzig electricity exchange, a reference market for off-exchange electricity trading, has operated in an environment marked by both criticism and acceptance. Taking this field of controversy as a point of departure the present empirical study in market sociology undertakes to investigate the organisation and latent functions of electricity exchange trading. The ensuing analysis provides answers to questions as to how prices are formed on the electricity exchange and what officially incommunicable functions are served by price formation on exchanges.

  3. Experimental determination of the 1 Sigma(+) state electric dipole moment function of carbon monoxide up to a large internuclear separation

    Science.gov (United States)

    Chackerian, C., Jr.; Farrenq, R.; Guelachvili, G.; Rossetti, C.; Urban, W.

    1984-01-01

    Experimental intensity information is combined with numerically obtained vibrational wave functions in a nonlinear least-squares fitting procedure to obtain the ground electronic state electric dipole moment function of carbon monoxide valid in the range of nuclear oscillation (0.87-1.91 A) of about the V = 38th vibrational level. Vibrational transition matrix elements are computed from this function for Delta V = 1, 2, 3 with V not more than 38.

  4. A microcontroller platform for the rapid prototyping of functional electrical stimulation-based gait neuroprostheses.

    Science.gov (United States)

    Luzio de Melo, Paulo; da Silva, Miguel Tavares; Martins, Jorge; Newman, Dava

    2015-05-01

    Functional electrical stimulation (FES) has been used over the last decades as a method to rehabilitate lost motor functions of individuals with spinal cord injury, multiple sclerosis, and post-stroke hemiparesis. Within this field, researchers in need of developing FES-based control solutions for specific disabilities often have to choose between either the acquisition and integration of high-performance industry-level systems, which are rather expensive and hardly portable, or develop custom-made portable solutions, which despite their lower cost, usually require expert-level electronic skills. Here, a flexible low-cost microcontroller-based platform for rapid prototyping of FES neuroprostheses is presented, designed for reduced execution complexity, development time, and production cost. For this reason, the Arduino open-source microcontroller platform was used, together with off-the-shelf components whenever possible. The developed system enables the rapid deployment of portable FES-based gait neuroprostheses, being flexible enough to allow simple open-loop strategies but also more complex closed-loop solutions. The system is based on a modular architecture that allows the development of optimized solutions depending on the desired FES applications, even though the design and testing of the platform were focused toward drop foot correction. The flexibility of the system was demonstrated using two algorithms targeting drop foot condition within different experimental setups. Successful bench testing of the device in healthy subjects demonstrated these neuroprosthesis platform capabilities to correct drop foot.

  5. Aging assessment of Westinghouse PWR and General Electric BWR containment isolation functions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.S.; Travis, R.; Grove, E.; DiBiasio, A.

    1996-03-01

    A study was performed to assess the effects of aging on the Containment Isolation (CI) functions of Westinghouse Pressurized Water Reactors and General Electric Boiling Water Reactors. This study is part of the Nuclear Plant Aging Research (NPAR) program, sponsored by the U.S. Nuclear Regulatory Commission. The objectives of this program are to provide an understanding of the aging process and how it affects plant safety so that it can be properly managed. This is one of a number of studies performed under the NPAR program which provide a technical basis for the identification and evaluation of degradation caused by age. Failure data from two national databases, Nuclear Plant Reliability Data System (NPRDS) and Licensee Event Reports (LERs), as well as plant specific data were reviewed and analyzed to understand the effects of aging on the CI functions. This study provided information on the effects of aging on component failure frequency, failure modes, and failure causes. Current inspection, surveillance, and monitoring practices were also reviewed.

  6. Event related desynchronization-modulated functional electrical stimulation system for stroke rehabilitation: A feasibility study

    Directory of Open Access Journals (Sweden)

    Takahashi Mitsuru

    2012-08-01

    Full Text Available Abstract Background We developed an electroencephalogram-based brain computer interface system to modulate functional electrical stimulation (FES to the affected tibialis anterior muscle in a stroke patient. The intensity of FES current increased in a stepwise manner when the event-related desynchronization (ERD reflecting motor intent was continuously detected from the primary cortical motor area. Methods We tested the feasibility of the ERD-modulated FES system in comparison with FES without ERD modulation. The stroke patient who presented with severe hemiparesis attempted to perform dorsiflexion of the paralyzed ankle during which FES was applied either with or without ERD modulation. Results After 20 minutes of training, the range of movement at the ankle joint and the electromyography amplitude of the affected tibialis anterior muscle were significantly increased following the ERD-modulated FES compared with the FES alone. Conclusions The proposed rehabilitation technique using ERD-modulated FES for stroke patients was feasible. The system holds potentials to improve the limb function and to benefit stroke patients.

  7. Feasibility of using Lokomat combined with functional electrical stimulation for the rehabilitation of foot drop

    Directory of Open Access Journals (Sweden)

    Christian B. Laursen

    2016-08-01

    Full Text Available This study investigated the clinical feasibility of combining the electromechanical gait trainer Lokomat with functional electrical therapy (LokoFET, stimulating the common peroneal nerve during the swing phase of the gait cycle to correct foot drop as an integrated part of gait therapy. Five patients with different acquired brain injuries trained with LokoFET 2-3 times a week for 3-4 weeks. Pre- and post-intervention evaluations were performed to quantify neurophysiological changes related to the patients’ foot drop impairment during the swing phase of the gait cycle. A semi-structured interview was used to investigate the therapists’ acceptance of LokoFET in clinical practice. The patients showed a significant increase in the level of activation of the tibialis anterior muscle and the maximal dorsiflexion during the swing phase, when comparing the pre- and post-intervention evaluations. This showed an improvement of function related to the foot drop impairment. The interview revealed that the therapists perceived the combined system as a useful tool in the rehabilitation of gait. However, lack of muscle selectivity relating to the FES element of LokoFET was assessed to be critical for acceptance in clinical practice.

  8. Electrical conductivity of mantle clinopyroxene as a function of water content and its implication on electrical structure of uppermost mantle

    Science.gov (United States)

    Zhao, Chengcheng; Yoshino, Takashi

    2016-08-01

    The electrical conductivity of San Carlos clinopyroxene aggregates with various water contents were measured under Ni-NiO buffer at 1.5 GPa and 600-1200 K in a DIA-type apparatus. The conductivity increases with increasing water content in clinopyroxene. Hidden conduction mechanism was detected because of the much smaller iron content in clinopyroxene, which was usually covered by small polaron conduction in other nominally anhydrous minerals. The identified activation enthalpies ranged from 0.70-0.75 eV to 1.23-1.37 eV. Our result reveals that the dominant charge-carrying species in electrical conductivity could change with temperature and water content. At high temperatures relevant to asthenospheric condition, activation enthalpy for the conductivity agrees well with that for the hydrogen self-diffusion. The dominant charge carrier therefore might be M site vacancy. However, contrary to previous view that all hydrogens contribute to increasing conductivity equally, our result shows that only a limited amount (20%-40%) of hydrogen acts as effective charge carrier in clinopyroxene. On the other hand, the activation enthalpy for the conductivity at low temperatures is significantly lower than that for the hydrogen self-diffusion, similar to what has been observed in olivine and orthopyroxene. This type of conduction is probably caused by fast diffusion of specific hydrogen or fast hydrogen grain boundary diffusion. At low temperatures, the proton conduction of clinopyroxene is nearly one order and two orders of magnitude lower than those of olivine and orthopyroxene, respectively, and tends to converge at high temperatures. Using the present data combined with conductivity of olivine and orthopyroxene, a laboratory-based conductivity-depth profile in the uppermost mantle shows that hydrous clinopyroxene cannot account for the high conductive regions observed beneath the ocean floor near Eastern Pacific Rise. The presence of partial melt would be unavoidable.

  9. Electricity economics

    CERN Document Server

    Hu, Zhaoguang

    2013-01-01

    Systematically analyzing for the first time the production output from electricity consumption for enterprises, sectors, and industries, this study uses the function of EAI (electricity as input), and includes national E-GDP figures for more than 20 countries.

  10. ALTERATION OF MUSCLE FUNCTION AFTER ELECTRICAL STIMULATION BOUT OF KNEE EXTENSORS AND FLEXORS

    Directory of Open Access Journals (Sweden)

    Marc Vanderthommen

    2012-12-01

    Full Text Available The purpose was to study the effects on muscle function of an electrical stimulation bout applied unilaterally on thigh muscles in healthy male volunteers. One group (ES group, n = 10 received consecutively 100 isometric contractions of quadriceps and 100 isometric contractions of hamstrings (on-off ratio 6-6 s induced by neuromuscular electrical stimulations (NMES. Changes in muscle torque, muscle soreness (0-10 VAS, muscle stiffness and serum creatine kinase (CK activity were assessed before the NMES exercise (pre-ex as well as 24h (d+1, 48h (d+2 and 120h (d+5 after the bout. A second group (control group, n = 10 were submitted to the same test battery than the ES group and with the same time-frame. The between-group comparison indicated a significant increase in VAS scores and in serum levels of CK only in the ES group. In the ES group, changes were more pronounced in hamstrings than in quadriceps and peaked at d+2 (quadriceps VAS scores = 2.20 ± 1.55 a.u. (0 at pre-ex; hamstrings VAS scores = 3.15 ± 2.14 a.u. (0 at pre-ex; hip flexion angle = 62 ± 5° (75 ± 6° at pre-ex; CK activity = 3021 ± 2693 IU·l-1 (136 ± 50 IU·l-1 at pre-ex. The results of the present study suggested the occurrence of muscle damage that could have been induced by the peculiar muscle recruitment in NMES and the resulting overrated mechanical stress. The sensitivity to the damaging effects of NMES appeared higher in the hamstrings than in quadriceps muscles

  11. Analytic investigation of effect of electric field on elasto-plastic response of a functionally graded piezoelectric hollow sphere

    Energy Technology Data Exchange (ETDEWEB)

    Atai, Ali Asghar [University of Tehran, Tehran (Iran, Islamic Republic of); Lak, Davaod [National Iranian Oil Co., Tehran (Iran, Islamic Republic of)

    2016-01-15

    In this work, the effect of electric potential on the mechanical (Stresses, strains, displacement) and electrical (electrical displacement and intensity) response of a Functionally graded piezoelectric (FGP) hollow sphere is analytically investigated. The sphere is under the action of internal/external pressure and temperature gradient as well. The inhomogeneity is based on power law in radial direction. The analysis is done in two parts: elastic response and plastic response, using Tresca yield criterion. It is shown by illustrative example that under internal pressure and assumed model parameters, the commencement of plastic region is from outside surface towards inside in the plastic zone is extended with the increase of electric potential. Interestingly, radial stress and displacement have an extreme not on the boundaries, but on the inside.

  12. [Preoperative direct cortical and sub-cortical electric stimulation during cerebral surgery in functional areas].

    Science.gov (United States)

    Duffau, H; Capelle, L; Sichez, J P; Bitar, A; Faillot, T; Arthuis, F; Van Effenterre, R; Fohanno, D

    1999-09-01

    Indications of surgical treatment for lesions in functional cerebral areas depend on the ratio between the definitive neurological deficit and the beneficial effect of resection. Detection of eloquent cortex is difficult because of important individual variability. Peroperative direct cortical and subcortical electrical stimulations (DCS) provide the most precise and reliable method currently available allowing identification and preservation of neurons essential for motricity, sensitivity++ and language. We report our preliminary experience with DCS in surgery of intracerebral infiltrative tumors with a consecutive series of 15 patients operated from November 96 through September 97 in our institution. Presenting symptoms in the 15 patients (8 males, 7 females, mean age 43 years) were seizures in 11 cases (73%) and neurological deficit in 4 cases (27%). Clinical examination was normal in 11 patients and revealed hemiparesia in 4. Magnetic resonance imaging (MRI) with three-dimensional reconstruction showed a precentral tumor in 10 cases, central lesion in one patient, postcentral lesion in two cases, right insular tumor (non-dominant hemisphere) in one case. All patients underwent surgical resection using DCS with detection in 13 cases of motor cortex and subcortical pathways under genera anesthesia, in one case of somatosensory area under local anesthesia, and in one case of language areas also under local anesthesia. The tumor was recurrent in two patients had been operated earlier but without DCS. Resection, verified by postoperative MRI, was total in 12 cases (80%) and estimated at 80% in 3 patients. Histological examination revealed an infiltrative glioma in 12 cases (8 low grade astrocytomas, 3 low grade oligodendrogliomas, and one anaplastic oligodendroglioma), and metastases in 3 cases. Eight patients had no postoperative deficit, while the other 7 patients were impaired, with, in all cases except one, complete recovery in 15 days to 2 months. Direct

  13. Monitoring muscle metabolic indexes by time-domain near infrared spectroscopy during knee flex-extension induced by functional electrical stimulation

    Science.gov (United States)

    Torricelli, Alessandro; Contini, Davide; Spinelli, Lorenzo; Cubeddu, Rinaldo; Molteni, Franco; Ferrante, Simona; Pedrocchi, Alessandra; Ferrigno, Giancarlo

    2007-07-01

    A time-domain NIRS multichannel system was used to monitor hemodynamic changes in the muscle of volunteers and hemiplegic patients during functional electrical stimulation for rehabilitation purposes.

  14. Enhancement of Isometric Ankle Dorsiflexion by Automyoelectrically Controlled Functional Electrical Stimulation on Subjects with Upper Motor Neuron Lesions

    NARCIS (Netherlands)

    Thorsen, R.; Ferrarin, M.; Veltink, P.

    2002-01-01

    The objective of this study was to test myoelectrically controlled functional electrical stimulation of the same muscle (AutoMCS) on patients with either stroke or spinal cord injury. The paretic anterior tibialis (TA) muscle was stimulated with an amplitude controlled continuously by the volitional

  15. Plane polymer configurations enclosing a fixed area in an electric field: generating functional and statistical mechanical properties

    NARCIS (Netherlands)

    Khandekar, D.C.; Wiegel, F.W.

    1993-01-01

    The statistical mechanical properties of plane polymer configurations which enclose a fixed area and are subject to an external electric field are investigated. For this purpose an exact expression for the generating functional is obtained and subsequently used to derive: (a) the distribution functi

  16. Effects of preoperative neuromuscular electrical stimulation on quadriceps strength and functional recovery in total knee arthroplasty. A pilot study.

    LENUS (Irish Health Repository)

    Walls, Raymond J

    2010-01-01

    Supervised preoperative muscle strengthening programmes (prehabilitation) can improve recovery after total joint arthroplasty but are considered resource intensive. Neuromuscular electrical stimulation (NMES) has been shown to improve quadriceps femoris muscle (QFM) strength and clinical function in subjects with knee osteoarthritis (OA) however it has not been previously investigated as a prehabilitation modality.

  17. Neurotherapeutic and neuroprosthetic effects of implanted functional electrical stimulation for ambulation after incomplete spinal cord injury

    Directory of Open Access Journals (Sweden)

    Ronald J. Triolo, PhD

    2010-03-01

    Full Text Available The purpose of this single-subject study was to determine the neurotherapeutic and neuroprosthetic effects of an implanted functional electrical stimulation (FES system designed to facilitate walking in an individual with a long-standing motor and sensory incomplete spinal cord injury. An implanted pulse generator and eight intramuscular stimulating electrodes were installed unilaterally, activating weak or paralyzed hip flexors, hip and knee extensors, and ankle dorsiflexors during 36 sessions of gait training with FES. The neurotherapeutic effects were assessed by a comparison of pre- and posttraining volitional walking. The neuroprosthetic effects were assessed by a comparison of posttraining volitional and FES-assisted walking. Treatment resulted in significant (p < 0.005 volitional improvements in 6-minute walking distance and speed, speed during maximum walk, double support time, and 10 m walking speed. Posttraining FES-assisted walking resulted in significant additional improvements in all these measures, except 10 m walking speed. When the subject was using FES-assisted gait, maximum walking distance, peak knee flexion in swing, peak ankle dorsiflexion in swing, and knee extension moment also significantly increased. Neuroprosthetic gains were sufficient to enable the subject to advance from household ambulation to limited community ambulation. Additionally, the subject could perform multiple walks per day when using FES-assisted gait, which was impossible with volitional effort alone.

  18. Electrical response and functionality of polymer matrix-titanium carbide composites

    Directory of Open Access Journals (Sweden)

    2010-04-01

    Full Text Available The dielectric response and conductivity of polymer matrix-titanium carbide composites was examined by means of Broadband Dielectric Spectroscopy in the frequency range of 10–1–107 Hz and over the temperature range of 40–150°C, varying the filler content. Dielectric data were analyzed via the electric modulus formalism. Recorded relaxations were attributed to interfacial polarization, glass to rubber transition and local motions of polar side groups. Alternating current conductivity varies up to seven orders of magnitude with both frequency and temperature. Direct current conductivity increases with temperature, although the rate of its alteration does not remain constant in the examined temperature range. In the low temperature region (up to 60°C increases at a higher rate, while right afterwards approaches rather constant values. Finally, in the high temperature range (above 90°C conductivity raises again but at a lower rate. This behaviour adds functionality to the composites’ performance and could be exploited in developing self-current regulators.

  19. A New system for Measuring Electrical Conductivity of Water as a Function of Admittance

    Directory of Open Access Journals (Sweden)

    Haval Yacoob

    2011-12-01

    Full Text Available This paper presents a new system for measuring water conductivity as a function of electrophysical property (admittance. The system is cheap and its manufacturing is easy. In addition, it dose not require any sort of electrolysis and calibration. The system consists of four electrodes made of silver (Ag 92.5 g to Cu 7.5 g fixed in a plastic tube filled by water which allows the use of two and four electrode setups. The admittance (reciprocal of impedance is measured for different water sources (distilled, rainfall, mineral, river and tap water using different frequencies between 50 Hz and 100 kHz. These measurements were taken twice, once with four electrodes and another with two electrodes of two modes (inner and outer electrodes. The results have shown good correlation between the measured admittance and the conductivity of all the water sources and the best correlation was found at low frequencies between 50 Hz and 20 kHz. The highest efficiency can be achieved by performing the four electrodes system which allows circumventing the effect of the electrode impedance. This result makes the system efficient compared to traditional conductivity meters which usually require high frequencies for good operation. doi:10.5617/jeb.203 J Electr Bioimp, vol. 2, pp. 86-92, 2011

  20. Correlation between spectral and temporal mechanomyography features during functional electrical stimulation

    Directory of Open Access Journals (Sweden)

    Eddy Krueger

    Full Text Available Abstract Introduction: Signal analysis involves time and/or frequency domains, and correlations are described in the literature for voluntary contractions. However, there are few studies about those correlations using mechanomyography (MMG response during functional electrical stimulation (FES elicited contractions in spinal cord injured subjects. This study aimed to determine the correlation between spectral and temporal MMG features during FES application to healthy (HV and spinal cord injured volunteers (SCIV. Methods: Twenty volunteers participated in the research divided in two groups: HV (N=10 and SCIV (N=10. The protocol consisted of four FES profiles transcutaneously applied to quadriceps femoris muscle via femoral nerve. Each application produced a sustained knee extension greater than 65º up to 2 min without adjusting FES intensity. The investigation involved the correlation between MMG signal root mean square (RMS and mean frequency (MF. Results: HV and SCIV indicated that MMGRMS and MMGMF variations were inversely related with -0.12 ≥ r ≥ -0.82. The dispersion between MMGMF and MMGRMS reached 0.50 ≤ r2 ≤ 0.64. Conclusion The increase in MMGRMS and the decrease in MMGMF may be explained by the motor units coherence during fatigue state or by motor neuron adaptation (habituation along FES application (without modification on parameters.

  1. Novel Walking Stability-Based Gait Recognition Method for Functional Electrical Stimulation System Control

    Institute of Scientific and Technical Information of China (English)

    MING Dong; WAN Baikun; HU Yong; WANG Yan; WANG Weijie; WU Yinghua; LU Dieji

    2007-01-01

    Gait recognition is the key question of functional electrical stimulation (FES) system control for paraplegic walking. A new risk-tendency-graph (RTG) method was proposed to recognize the stability information in FES-assisted walking gait. The main instrument was a specialized walker dynamometer system based on a multi-channel strain-gauge bridge network fixed on the walker frame. During walking process, this system collected the reaction forces between patient's upper extremities and walker and converted them into RTG morphologic curves of dynamic gait stability in temporal and spatial domains.To demonstrate the potential usefulness of RTG, preliminary clinical trials were done with paraplegic patients. The gait stability levels of two walking cases with 4- and 12-week FES training from one subject were quantified (0.43 and 0.19) from the results of temporal and spatial RTG. Relevant instable phases in gait cycle and dangerous inclinations of patient's body during walking process were also brought forward. In conclusion, the new RTG method is practical for distinguishing more useful gait stability information for FES system control.

  2. Gait phase detection from sciatic nerve recordings in functional electrical stimulation systems for foot drop correction.

    Science.gov (United States)

    Chu, Jun-Uk; Song, Kang-Il; Han, Sungmin; Lee, Soo Hyun; Kang, Ji Yoon; Hwang, Dosik; Suh, Jun-Kyo Francis; Choi, Kuiwon; Youn, Inchan

    2013-05-01

    Cutaneous afferent activities recorded by a nerve cuff electrode have been used to detect the stance phase in a functional electrical stimulation system for foot drop correction. However, the implantation procedure was difficult, as the cuff electrode had to be located on the distal branches of a multi-fascicular nerve to exclude muscle afferent and efferent activities. This paper proposes a new gait phase detection scheme that can be applied to a proximal nerve root that includes cutaneous afferent fibers as well as muscle afferent and efferent fibers. To test the feasibility of this scheme, electroneurogram (ENG) signals were measured from the rat sciatic nerve during treadmill walking at several speeds, and the signal properties of the sciatic nerve were analyzed for a comparison with kinematic data from the ankle joint. On the basis of these experiments, a wavelet packet transform was tested to define a feature vector from the sciatic ENG signals according to the gait phases. We also propose a Gaussian mixture model (GMM) classifier and investigate whether it could be used successfully to discriminate feature vectors into the stance and swing phases. In spite of no significant differences in the rectified bin-integrated values between the stance and swing phases, the sciatic ENG signals could be reliably classified using the proposed wavelet packet transform and GMM classification methods.

  3. Efficacy of EMG/bioimpedance-triggered functional electrical stimulation on swallowing performance

    Directory of Open Access Journals (Sweden)

    Corinna Schultheiss

    2016-08-01

    Full Text Available In order to support swallowing, the efficacy of functional electrical stimulation for different stimulation settings of the submental musculature has been investigated. The stimulation was administrated at rest and synchronously to voluntary initiated swallows. The onset of a swallow was detected in real-time by a combined electromyography/ bioimpedance measurement at the neck in order to trigger the stimulation. The amplitude and speed of larynx elevation caused by the FES has been assessed by the observed change in bioimpedance whereas a reduction of bioimpedance corresponds to an increase in larynx elevation. Study results from 40 healthy subjects revealed that 73% of the subjects achieved a larger and faster larynx elevation during swallowing with triggered FES and therefor a better protection of their airways. However, we also observed a decrease in larynx elevation compared to normal swallowing in 11 out of the 40 subjects what might not benefit from such a treatment. The largest improvement of larynx elevation and speed during swallowing could be achieved with three stimulation channels formed by four electrodes in the submental region.

  4. Early Poststroke Rehabilitation Using a Robotic Tilt-Table Stepper and Functional Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Alexey N. Kuznetsov

    2013-01-01

    Full Text Available Background. Stroke frequently leaves survivors with hemiparesis. To prevent persistent deficits, rehabilitation may be more effective if started early. Early training is often limited because of orthostatic reactions. Tilt-table stepping robots and functional electrical stimulation (FES may prevent these reactions. Objective. This controlled convenience sample study compares safety and feasibility of robotic tilt-table training plus FES (ROBO-FES and robotic tilt-table training (ROBO against tilt-table training alone (control. A preliminary assessment of efficacy is performed. Methods. Hemiparetic ischemic stroke survivors (age years, days after stroke were assigned to 30 days of ROBO-FES (, ROBO (, or control ( in addition to conventional physical therapy. Impedance cardiography and transcranial doppler sonography were performed before, during, and after training. Hemiparesis was assessed using the British Medical Research Council (MRC strength scale. Results. No serious adverse events occurred; 8 patients in the tilt-table group prematurely quit the study because of orthostatic reactions. Blood pressure and CBFV dipped % during robot training. In 52% of controls mean arterial pressure decreased by %. ROBO-FES increased leg strength by points, ROBO by more than control (, . CBFV increased in both robotic groups more than in controls (. Conclusions. Robotic tilt-table exercise with or without FES is safe and may be more effective in improving leg strength and cerebral blood flow than tilt table alone.

  5. Evaluation of Functional Electrical Stimulation to Assist Cycling in Four Adolescents with Spastic Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Ann Tokay Harrington

    2012-01-01

    Full Text Available Introduction. Adolescents with cerebral palsy (CP often have difficulty participating in exercise at intensities necessary to improve cardiovascular fitness. Functional electrical stimulation- (FES- assisted cycling is proposed as a form of exercise for adolescents with CP. The aims of this paper were to adapt methods and assess the feasibility of applying FES cycling technology in adolescents with CP, determine methods of performing cycling tests in adolescents with CP, and evaluate the immediate effects of FES assistance on cycling performance. Materials/Methods. Four participants (12–14 years old; GMFCS levels III-IV participated in a case-based pilot study of FES-assisted cycling in which bilateral quadriceps muscles were activated using surface electrodes. Cycling cadence, power output, and heart rate were collected. Results. FES-assisted cycling was well tolerated (n=4 and cases are presented demonstrating increased cadence (2–43 rpm, power output (19–70%, and heart rates (4-5% and decreased variability (8–13% in cycling performance when FES was applied, compared to volitional cycling without FES assistance. Some participants (n=2 required the use of an auxiliary hub motor for assistance. Conclusions. FES-assisted cycling is feasible for individuals with CP and may lead to immediate improvements in cycling performance. Future work will examine the potential for long-term fitness gains using this intervention.

  6. Improving respiration in patients with tetraplegia by functional electrical stimulation: an anatomical perspective.

    Science.gov (United States)

    Bell, Sarah; Shaw-Dunn, John; Gollee, Henrik; Allan, David B; Fraser, Matthew H; McLean, Alan N

    2007-08-01

    Patients with tetraplegia often have respiratory complications because of paralysis of the abdominal and intercostal muscles. Functional electrical stimulation (FES) has been used to improve breathing in these patients by applying surface stimulation to the abdominal muscles. We aimed to find the best nerves to stimulate directly to increase tidal volume and make cough more effective. Surface electrodes were placed on a patient's abdominal wall to find the optimum points for surface stimulation. These positions were plotted on a transparent sheet. The abdomino-intercostal nerves were dissected in five male dissecting room cadavers matched for size with the patient. The plastic sheet was then superimposed over each of the dissections to clarify the relationship between optimum surface stimulation points and the underlying nerves. Results show that the optimum surface stimulation points overlie the course of abdomino-intercostal nerves T9, 10, and 11. The success with selecting stimulation points associated with T9, 10, and 11 is probably because of the large mass of abdominal muscle supplied by these nerves. The constant position of the nerves below the ribs makes the intercostal space a possible site for direct stimulation of the abdomino-intercostal nerves.

  7. Effects of Dual-Channel Functional Electrical Stimulation on Gait Performance in Patients with Hemiparesis

    Directory of Open Access Journals (Sweden)

    Shmuel Springer

    2012-01-01

    Full Text Available The study objective was to assess the effect of functional electrical stimulation (FES applied to the peroneal nerve and thigh muscles on gait performance in subjects with hemiparesis. Participants were 45 subjects (age 57.8 ± 14.8 years with hemiparesis (5.37 ± 5.43 years since diagnosis demonstrating a foot-drop and impaired knee control. Thigh stimulation was applied either to the quadriceps or hamstrings muscles, depending on the dysfunction most affecting gait. Gait was assessed during a two-minute walk test with/without stimulation and with peroneal stimulation alone. A second assessment was conducted after six weeks of daily use. The addition of thigh muscles stimulation to peroneal stimulation significantly enhanced gait velocity measures at the initial and second evaluation. Gait symmetry was enhanced by the dual-channel stimulation only at the initial evaluation, and single-limb stance percentage only at the second assessment. For example, after six weeks, the two-minute gait speed with peroneal stimulation and with the dual channel was 0.66 ± 0.30 m/sec and 0.70 ± 0.31 m/sec, respectively (. In conclusion, dual-channel FES may enhance gait performance in subjects with hemiparesis more than peroneal FES alone.

  8. Volatility transmission and volatility impulse response functions in European electricity forward markets

    Energy Technology Data Exchange (ETDEWEB)

    Le Pen, Yannick [Institut d' Economie et de Management de Nantes - IAE, Universite de Nantes, Chemin de la Censive du Tertre, BP 52231, 44322 Nantes cedex 3 (France); Sevi, Benoit [Universite d' Angers (GRANEM), Faculte de Droit, Economie et Gestion, Universite d' Angers, 13 allee Francois Mitterrand, BP 13633, 49036 Angers cedex 01 (France)

    2010-07-15

    Using daily data from March 2001 to June 2005, we estimate a VAR-BEKK model and find evidence of return and volatility spillovers between the German, the Dutch and the British forward electricity markets. We apply Hafner and Herwartz [2006, Journal of International Money and Finance 25, 719-740] Volatility Impulse Response Function (VIRF) to quantify the impact of shock on expected conditional volatility. We observe that a shock has a high positive impact only if its size is large compared to the current level of volatility. The impact of shocks are usually not persistent, which may be a consequence of the non-storability of power. Finally, we estimate the density of the VIRF at different forecast horizons. These fitted distributions are asymmetric and show that large increases in expected conditional volatilities are possible even if their probability is low. These results have interesting implications for market participants whose risk management policy depends on option prices which themselves depend on the characteristics of volatility. (author)

  9. Torsional electric dipole moment functions calculated for HOOH and ClOOCl

    Science.gov (United States)

    McGrath, Mark P.

    2013-03-01

    The periodic torsional, electric dipole moment (EDM) functions μ(ϕ) = ∑m = 0pmcos (m + 1/2)ϕ, of the atmospherically significant molecules HOOH and ClOOCl, have been derived from calculations at the CCSD(T) (coupled-cluster singles and doubles model, plus a noniterative triples correction) level of electronic-structure theory with augmented, correlation-consistent basis sets extrapolated to the approximate complete basis set limit. The μ(ϕ) of HOOH, defined by {pm} = {3.0979, -0.0301, -0.0058} D, is used to calculate squared transition EDMs that compare well with those previously derived using the experimental torsional line intensities. The μ(ϕ) of ClOOCl, defined by μ(ϕ) = {1.1935, 0.1163, 0.1341, -0.0040, -0.0099} D, requires a longer Fourier expansion because, in the range of dihedral angles from the cis (ϕ = 0) to the trans (ϕ = π) transition structures, three inflection points are found for ClOOCl, but only one for HOOH. The permanent EDM calculated for HOOH, 1.754 D, is in close agreement with the value deduced from experiment. Compared to HOOH, the permanent EDM vector calculated for ClOOCl is directed analogously, but has a significantly smaller magnitude, 0.700 D.

  10. Volitional cycling augmented by functional electrical stimulation in hemiparetic adolescents: A case series study

    Directory of Open Access Journals (Sweden)

    Peri Elisabetta

    2013-01-01

    Full Text Available The aim of this work was to assess the feasibility of a treatment based on volitional cycling augmented by Functional Electrical Stimulation (FES on hemiparetic adolescents. Six chronic hemiparetic adolescents were included in a case series study. Patients underwent FES-cycling training combined with voluntary pedaling. The intervention consisted of 21 sessions lasting 30 minutes each. Patients were evaluated before, after training, and at a 3-month follow-up visit through clinical scales (Winter scale, observational gait scale, gross motor function measurement, Boyd test and Ashworth scale, a standard gait analysis and a voluntary pedaling test. Results were compared with an age-matched healthy control group (N=6. Two subjects withdrew the study before the completion of the intervention. Concerning the four remaining subjects, the clinical scales showed a slight level of disability already at baseline and no changes were observed after the intervention. In terms of walking ability, some significant improvements (Kruskal-Wallis test, p-value<0.05 were obtained after training in two out of four subjects: an increase of about 16% and 41% of the ankle range of motion and of about 18% and 33% of the ankle propelling power were achieved for two subjects, respectively. During pedaling, the work produced by the paretic leg while pulling the pedal significantly increased in 3 out of 4 subjects. In one subject a more symmetrical cycling movement was observed, whilst for another subject a significant improvement in terms of co-contraction between rectus femoris and biceps femoris was achieved. In conclusion, this study assessed the feasibility of FES-cycling training on hemiparetic adolescents, but did not provide evidences about the effectiveness of this intervention in improving motor recovery and walking ability. However, since only a small group of patients with a low level of disability was involved in the study, further investigations are needed to

  11. Functional electrical stimulation to the abdominal wall muscles synchronized with the expiratory flow does not induce muscle fatigue

    Science.gov (United States)

    Okuno, Yukako; Takahashi, Ryoichi; Sewa, Yoko; Ohse, Hirotaka; Imura, Shigeyuki; Tomita, Kazuhide

    2017-01-01

    [Purpose] Continuous electrical stimulation of abdominal wall muscles is known to induce mild muscle fatigue. However, it is not clear whether this is also true for functional electrical stimulation delivered only during the expiratory phase of breathing. This study aimed to examine whether or not intermittent electrical stimulation delivered to abdominal wall muscles induces muscle fatigue. [Subjects and Methods] The subjects were nine healthy adults. Abdominal electrical stimulation was applied for 1.5 seconds from the start of expiration and then turned off during inspiration. The electrodes were attached to both sides of the abdomen at the lower margin of the 12th rib. Abdominal electrical stimulation was delivered for 15 minutes with the subject in a seated position. Expiratory flow was measured during stimulus. Trunk flexor torque and electromyography activity were measured to evaluate abdominal muscle fatigue. [Results] The mean stimulation on/off ratio was 1:2.3. The declining rate of abdominal muscle torque was 61.1 ± 19.1% before stimulus and 56.5 ± 20.9% after stimulus, not significantly different. The declining rate of mean power frequency was 47.8 ± 11.7% before stimulus and 47.9 ± 10.2% after stimulus, not significantly different. [Conclusion] It was found that intermittent electrical stimulation to abdominal muscles synchronized with the expiratory would not induce muscle fatigue. PMID:28356636

  12. Functional electrical stimulation to the abdominal wall muscles synchronized with the expiratory flow does not induce muscle fatigue.

    Science.gov (United States)

    Okuno, Yukako; Takahashi, Ryoichi; Sewa, Yoko; Ohse, Hirotaka; Imura, Shigeyuki; Tomita, Kazuhide

    2017-03-01

    [Purpose] Continuous electrical stimulation of abdominal wall muscles is known to induce mild muscle fatigue. However, it is not clear whether this is also true for functional electrical stimulation delivered only during the expiratory phase of breathing. This study aimed to examine whether or not intermittent electrical stimulation delivered to abdominal wall muscles induces muscle fatigue. [Subjects and Methods] The subjects were nine healthy adults. Abdominal electrical stimulation was applied for 1.5 seconds from the start of expiration and then turned off during inspiration. The electrodes were attached to both sides of the abdomen at the lower margin of the 12th rib. Abdominal electrical stimulation was delivered for 15 minutes with the subject in a seated position. Expiratory flow was measured during stimulus. Trunk flexor torque and electromyography activity were measured to evaluate abdominal muscle fatigue. [Results] The mean stimulation on/off ratio was 1:2.3. The declining rate of abdominal muscle torque was 61.1 ± 19.1% before stimulus and 56.5 ± 20.9% after stimulus, not significantly different. The declining rate of mean power frequency was 47.8 ± 11.7% before stimulus and 47.9 ± 10.2% after stimulus, not significantly different. [Conclusion] It was found that intermittent electrical stimulation to abdominal muscles synchronized with the expiratory would not induce muscle fatigue.

  13. Conducting polymer scaffolds for electrical control of cellular functions (Conference Presentation)

    Science.gov (United States)

    Inal, Sahika; Wan, Alwin M.; Williams, Tiffany V.; Giannelis, Emmanuel P.; Fischbach-Teschl, Claudia; Gourdon, Delphine; Owens, Róisín. M.; Malliaras, George G.

    2016-09-01

    Considering the limited physiological relevance of 2D cell culture experiments, significant effort was devoted to the development of materials that could more accurately recreate the in vivo cellular microenvironment, and support 3D cell cultures in vitro. (1) One such class of materials is conducting polymers, which are promising due to their compliant mechanical properties, compatibility with biological systems, mixed electrical and ionic conductivity, and ability to form porous structures. (2) In this work, we report the fabrication of a single component, macroporous scaffold made from poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) via an ice-templating method. (3) PEDOT:PSS scaffolds offer tunable pore size, morphology and shape through facile changes in preparation conditions, and are capable of supporting 3D cell cultures due to their biocompatibility and tissue-like elasticity. Moreover, these materials are functional: they exhibit excellent electrochemical switching behavior and significantly lower impedance compared to films. Their electrochemical activity enables their use in the active channel of a state of the art diagnostic tool in the field of bioelectronics, i.e., the organic electrochemical transistor (OECT). The inclusion of cells within the porous architecture affects the impedance of the electrically-conducting polymer network and, thus, may be used as a method to quantify cell growth. The adhesion and pro-angiogenic secretions of mouse fibroblasts cultured within the scaffolds can be controlled by switching the electrochemical state of the polymer prior to cell-seeding. In summary, these smart materials hold promise not only as extracellular matrix-mimicking structures for cell culture, but also as high-performance bioelectronic tools for diagnostic and signaling applications. References [1] M. Holzwarth, P. X. Ma, Journal of Materials Chemistry, 21, 10243-10251 (2011). [2] L. H. Jimison, J. Rivnay, R. M. Owens, in Organic

  14. Electrical Grid Conditioning For First NPP Integration, a Systems Engineering Approach Incorporating Quality Function Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Pwani, Henry; James, J. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2013-10-15

    Nuclear power plant has a high potential to cause serious harm to environment as evidenced by effects of Fukushima and Chernobyl accidents. A reliable electrical power is required for a NPP to facilitate cooling after a shutdown. Failure of electrical power supply during shutdown increases core damage probability. Research shows that a total of 39% of LOOP related events in US are electrical grid centered. In Korea, 38% and 29% of all events that led to NPP shutdown at Hanul units 3-6 and at Hanbit units 3-6 respectively were electrical related. Electric grids for both operating and new NPPs must therefore be examined and upgraded for reliability improvement in order to enhance NPP safety.

  15. Effects of Electric Stimulations Applied during Absolute Refractory Period on Cardiac Function of Rabbits with Heart Failure

    Institute of Scientific and Technical Information of China (English)

    张海柱; 崔长琮; 胡大一

    2010-01-01

    The effects of electric currents applied during absolute refractory period(ARP) on the cardiac function of rabbits with heart failure due to myocardial infarction(MI),and the safety of this method were investigated.Thirty rabbits were randomly assigned equally to 3 groups:sham-operated group,LV-anterior wall cardiac contractility modulation(LV-CCM) group,and septum-CCM(S-CCM) group.A thoracotomy was performed on all the rabbits.Electric pulses were delivered during the ARP on the anterior wall of left ventr...

  16. Dynamics of completely unfolded and native proteins through solid-state nanopores as a function of electric driving force.

    Science.gov (United States)

    Oukhaled, Abdelghani; Cressiot, Benjamin; Bacri, Laurent; Pastoriza-Gallego, Manuela; Betton, Jean-Michel; Bourhis, Eric; Jede, Ralf; Gierak, Jacques; Auvray, Loïc; Pelta, Juan

    2011-05-24

    We report experimentally the dynamic properties of the entry and transport of unfolded and native proteins through a solid-state nanopore as a function of applied voltage, and we discuss the experimental data obtained as compared to theory. We show an exponential increase in the event frequency of current blockades and an exponential decrease in transport times as a function of the electric driving force. The normalized current blockage ratio remains constant or decreases for folded or unfolded proteins, respectively, as a function of the transmembrane potential. The unfolded protein is stretched under the electric driving force. The dwell time of native compact proteins in the pore is almost 1 order of magnitude longer than that of unfolded proteins, and the event frequency for both protein conformations is low. We discuss the possible phenomena hindering the transport of proteins through the pores, which could explain these anomalous dynamics, in particular, electro-osmotic counterflow and protein adsorption on the nanopore wall.

  17. Conducted electrical weapon incapacitation during a goal-directed task as a function of probe spread.

    Science.gov (United States)

    Ho, Jeffrey; Dawes, Donald; Miner, James; Kunz, Sebastian; Nelson, Rebecca; Sweeney, James

    2012-12-01

    Despite training and field experience that the location and spread between conducted electrical weapon (CEW) probes is important in establishing incapacitation, there have been no human studies which have systematically examined the relationships between probe spread and incapacitation. We have investigated this relationship with the TASER(®) X26. We have also developed and validated methodologies for prospective assessment of the effectiveness of CEWs in the incapacitation of highly motivated human subjects. Subjects (n = 30) had probes placed on the front or back with randomly varied spreads in accordance with recommended targeting zones. Subjects were motivated to complete the task of disabling the device or a dummy officer suspended ten feet away during the exposure while using a training knife. Subjects were rated on their progress toward goal success and on the extent of any incapacitation using two separate observer scoring panels: one consisting of experts in physiology and X26 technology, and another of veteran peace officers. Incapacitation by all measures was found to be a function of spread; generally increasing in effectiveness up to spreads between 9 and 12 in. There were notable differences between front and back exposures, with front exposures not leading to full incapacitation of the upper extremities regardless of probe spread. This is the first published study on a quantitative methodology for directly assessing the effectiveness of CEWs in human incapacitation. We have also validated and quantified for the first time in human subjects that establishing a minimal spread between X26 probes correlates to the extent of device effectiveness.

  18. Mechanical and electrical properties of functionalized graphene nanoribbon: A study of reactive molecular dynamic simulation and density functional tight-binding theory

    Energy Technology Data Exchange (ETDEWEB)

    Zaminpayma, Esmaeil, E-mail: zaminpayma@qiau.ac.ir [Physics Group, Qazvin Branch, Islamic Azad University, Qazvin (Iran, Islamic Republic of); Nayebi, Payman [Physics Department, Saveh Branch, Islamic Azad University, Saveh (Iran, Islamic Republic of)

    2015-02-15

    Graphene has novel electronic structure, such as unusual transport properties, high carrier mobility and excellent mechanical properties like high Young's modulus. These properties can be modified by many methods, such as functionalized with adding chemical groups, cutting graphene as a nanoribbon and Appling a stress along graphene. In this work, we studied the mechanical and electrical properties of functionalized graphene nanoribbon with –NH{sub 2}, –CH{sub 3}, –OH, –C{sub 5}H{sub 6} groups. In mechanical section, we calculated Young's modulus of functionalized graphene nanoribbon as a function of temperature by method of reactive molecular dynamic simulation. Our results show that Young's modulus decrease by increasing temperature. Also we studied the effect of functionalized groups on Young's modulus. We show that Young's modulus decreases by adding these groups. It is in the order of Y (nanoribbon)>Y (NH{sub 2})>Y (C{sub 6}H{sub 5})>Y (OH)>Y (CH{sub 3}). In electrical section, we calculated current–voltage curve for functionalized nanoribbon with density functional tight-binding method at two different 0% and 5% strain. We found for both strains, the functionalized groups decrease the electrical resistance of nanoribbon and increase its current. The relationship of the current is in the order of I(CH{sub 3}) >I(C{sub 5}H{sub 6}) >I(NH{sub 2}) >I(OH) >I (nanoribbon)

  19. Vertical electric field stimulated neural cell functionality on porous amorphous carbon electrodes.

    Science.gov (United States)

    Jain, Shilpee; Sharma, Ashutosh; Basu, Bikramjit

    2013-12-01

    We demonstrate the efficacy of amorphous macroporous carbon substrates as electrodes to support neuronal cell proliferation and differentiation in electric field mediated culture conditions. The electric field was applied perpendicular to carbon substrate electrode, while growing mouse neuroblastoma (N2a) cells in vitro. The placement of the second electrode outside of the cell culture medium allows the investigation of cell response to electric field without the concurrent complexities of submerged electrodes such as potentially toxic electrode reactions, electro-kinetic flows and charge transfer (electrical current) in the cell medium. The macroporous carbon electrodes are uniquely characterized by a higher specific charge storage capacity (0.2 mC/cm(2)) and low impedance (3.3 kΩ at 1 kHz). The optimal window of electric field stimulation for better cell viability and neurite outgrowth is established. When a uniform or a gradient electric field was applied perpendicular to the amorphous carbon substrate, it was found that the N2a cell viability and neurite length were higher at low electric field strengths (≤ 2.5 V/cm) compared to that measured without an applied field (0 V/cm). While the cell viability was assessed by two complementary biochemical assays (MTT and LDH), the differentiation was studied by indirect immunostaining. Overall, the results of the present study unambiguously establish the uniform/gradient vertical electric field based culture protocol to either enhance or to restrict neurite outgrowth respectively at lower or higher field strengths, when neuroblastoma cells are cultured on porous glassy carbon electrodes having a desired combination of electrochemical properties.

  20. Converting chemical energy into electricity through a functionally cooperating device with diving-surfacing cycles.

    Science.gov (United States)

    Song, Mengmeng; Cheng, Mengjiao; Ju, Guannan; Zhang, Yajun; Shi, Feng

    2014-11-05

    A smart device that can dive or surface in aqueous medium has been developed by combining a pH-responsive surface with acid-responsive magnesium. The diving-surfacing cycles can be used to convert chemical energy into electricity. During the diving-surfacing motion, the smart device cuts magnetic flux lines and produces a current, demonstrating that motional energy can be realized by consuming chemical energy of magnesium, thus producing electricity.

  1. Local changes of work function near rough features on Cu surfaces operated under high external electric field

    Energy Technology Data Exchange (ETDEWEB)

    Djurabekova, Flyura, E-mail: flyura.djurabekova@helsinki.fi; Ruzibaev, Avaz; Parviainen, Stefan [Helsinki Institute of Physics and Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 Helsinki (Finland); Holmström, Eero [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland); Department of Earth Sciences, Faculty of Maths and Physical Sciences, UCL Earth Sciences, Gower Street, London WC1E 6BT (United Kingdom); Hakala, Mikko [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland)

    2013-12-28

    Metal surfaces operated under high electric fields produce sparks even if they are held in ultra high vacuum. In spite of extensive research on the topic of vacuum arcs, the mystery of vacuum arc origin still remains unresolved. The indications that the sparking rates depend on the material motivate the research on surface response to extremely high external electric fields. In this work by means of density-functional theory calculations we analyze the redistribution of electron density on (100) Cu surfaces due to self-adatoms and in presence of high electric fields from −1 V/nm up to −2 V/nm (−1 to −2 GV/m, respectively). We also calculate the partial charge induced by the external field on a single adatom and a cluster of two adatoms in order to obtain reliable information on charge redistribution on surface atoms, which can serve as a benchmarking quantity for the assessment of the electric field effects on metal surfaces by means of molecular dynamics simulations. Furthermore, we investigate the modifications of work function around rough surface features, such as step edges and self-adatoms.

  2. Analysis of electricity distribution network operation business models and capitalization of control room functions with DMS

    Energy Technology Data Exchange (ETDEWEB)

    Tanskanen, A.

    2010-07-01

    Electricity distribution network operation (NO) models are challenged as they are expected to continue to undergo changes during the coming decades in the fairly developed and regulated Nordic electricity market. Network asset managers are to adapt to competitive technoeconomical business models regarding the operation of increasingly intelligent distribution networks. Factors driving the changes for new business models within network operation include: increased investments in distributed automation (DA), regulative frameworks for annual profit limits and quality through outage cost, increasing end-customer demands, climatic changes and increasing use of data system tools, such as Distribution Management System (DMS). The doctoral thesis addresses the questions a) whether there exist conditions and qualifications for competitive markets within electricity distribution network operation and b) if so, identification of limitations and required business mechanisms. This doctoral thesis aims to provide an analytical business framework, primarily for electric utilities, for evaluation and development purposes of dedicated network operation models to meet future market dynamics within network operation. In the thesis, the generic build-up of a business model has been addressed through the use of the strategic business hierarchy levels of mission, vision and strategy for definition of the strategic direction of the business followed by the planning, management and process execution levels of enterprise strategy execution. Research questions within electricity distribution network operation are addressed at the specified hierarchy levels. The results of the research represent interdisciplinary findings in the areas of electrical engineering and production economics. The main scientific contributions include further development of the extended transaction cost economics (TCE) for government decisions within electricity networks and validation of the usability of the

  3. Interaction of electrical stimulation and voluntary hand movement in SII and the cerebellum during simulated therapeutic functional electrical stimulation in healthy adults.

    Science.gov (United States)

    Iftime-Nielsen, Simona Denisia; Christensen, Mark Schram; Vingborg, Rune Jersin; Sinkjaer, Thomas; Roepstorff, Andreas; Grey, Michael James

    2012-01-01

    The therapeutic application of functional electrical stimulation (FES) has shown promising clinical results in the rehabilitation of post-stroke hemiplegia. It appears that the effect is optimal when the patterned electrical stimulation is used in close synchrony with voluntary movement, although the neural mechanisms that underlie the clinical successes reported with therapeutic FES are unknown. One possibility is that therapeutic FES takes advantage of the sensory consequences of an internal model. Here, we investigate fMRI cortical activity when FES is combined with voluntary effort (FESVOL) and we compare this activity to that produced when FES and voluntary activity (VOL) are performed alone. FESVOL revealed greater cerebellar activity compared with FES alone and reduced activity bilaterally in secondary somatosensory areas (SII) compared with VOL alone. Reduced activity was also observed for FESVOL compared with FES alone in the angular gyrus, middle frontal gyrus and inferior frontal gyrus. These findings indicate that during the VOL condition the cerebellum predicts the sensory consequences of the movement and this reduces the subsequent activation in SII. The decreased SII activity may reflect a better match between the internal model and the actual sensory feedback. The greater cerebellar activity coupled with reduced angular gyrus activity in FESVOL compared with FES suggests that the cortex may interpret sensory information during the FES condition as an error-like signal due to the lack of a voluntary component in the movement.

  4. Nanosecond pulsed platelet-rich plasma (nsPRP) improves mechanical and electrical cardiac function following myocardial reperfusion injury.

    Science.gov (United States)

    Hargrave, Barbara; Varghese, Frency; Barabutis, Nektarios; Catravas, John; Zemlin, Christian

    2016-02-01

    Ischemia and reperfusion (I/R) of the heart is associated with biochemical and ionic changes that result in cardiac contractile and electrical dysfunction. In rabbits, platelet-rich plasma activated using nanosecond pulsed electric fields (nsPRP) has been shown to improve left ventricular pumping. Here, we demonstrate that nsPRP causes a similar improvement in mouse left ventricular function. We also show that nsPRP injection recovers electrical activity even before reperfusion begins. To uncover the mechanism of nsPRP action, we studied whether the enhanced left ventricular function in nsPRP rabbit and mouse hearts was associated with increased expression of heat-shock proteins and altered mitochondrial function under conditions of oxidative stress. Mouse hearts underwent 30 min of global ischemia and 1 h of reperfusion in situ. Rabbit hearts underwent 30 min of ischemia in vivo and were reperfused for 14 days. Hearts treated with nsPRP expressed significantly higher levels of Hsp27 and Hsp70 compared to hearts treated with vehicle. Also, pretreatment of cultured H9c2 cells with nsPRP significantly enhanced the "spare respiratory capacity (SRC)" also referred to as "respiratory reserve capacity" and ATP production in response to the uncoupler FCCP. These results suggest a cardioprotective effect of nsPRP on the ischemic heart during reperfusion.

  5. Electrical stimulation as a treatment intervention to improve function, edema or pain following acute lateral ankle sprains: A systematic review.

    Science.gov (United States)

    Feger, Mark A; Goetschius, John; Love, Hailey; Saliba, Sue A; Hertel, Jay

    2015-11-01

    The purpose of this systematic review was to assess whether electrical stimulation (ES), when used in conjunction with a standard treatment, can reduce levels of functional impairment, edema, and pain compared to a standard treatment alone, in patients following a lateral ankle sprain. We searched PubMed, CINAHL, SportDiscus, and Medline (OVID) databases through June 2014 using the terms "ankle sprain or ankle sprains or ligament injury or ligamentous injury," and "electric stimulation or electric stimulation or electrotherapy." Our search identified four randomized control trials, of which, neuromuscular ES and high-voltage pulsed stimulation were the only two ES modalities utilized. Effect sizes and 95% confidence intervals (CI) were estimated using Cohen's d for comparison between treatment groups. Three of four effect sizes for function had 95% CI that crossed zero. Twenty-four of the thirty-two effect sizes for edema had 95% CI that crossed zero. All effect sizes for pain had 95% CI that crossed zero. Therefore, the use of ES is not recommended as a means to improve function, reduce edema, or decrease pain in the treatment of acute lateral ankle sprains.

  6. Updated greenhouse gas and criteria air pollutant emission factors and their probability distribution functions for electricity generating units

    Energy Technology Data Exchange (ETDEWEB)

    Cai, H.; Wang, M.; Elgowainy, A.; Han, J. (Energy Systems)

    2012-07-06

    Greenhouse gas (CO{sub 2}, CH{sub 4} and N{sub 2}O, hereinafter GHG) and criteria air pollutant (CO, NO{sub x}, VOC, PM{sub 10}, PM{sub 2.5} and SO{sub x}, hereinafter CAP) emission factors for various types of power plants burning various fuels with different technologies are important upstream parameters for estimating life-cycle emissions associated with alternative vehicle/fuel systems in the transportation sector, especially electric vehicles. The emission factors are typically expressed in grams of GHG or CAP per kWh of electricity generated by a specific power generation technology. This document describes our approach for updating and expanding GHG and CAP emission factors in the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model developed at Argonne National Laboratory (see Wang 1999 and the GREET website at http://greet.es.anl.gov/main) for various power generation technologies. These GHG and CAP emissions are used to estimate the impact of electricity use by stationary and transportation applications on their fuel-cycle emissions. The electricity generation mixes and the fuel shares attributable to various combustion technologies at the national, regional and state levels are also updated in this document. The energy conversion efficiencies of electric generating units (EGUs) by fuel type and combustion technology are calculated on the basis of the lower heating values of each fuel, to be consistent with the basis used in GREET for transportation fuels. On the basis of the updated GHG and CAP emission factors and energy efficiencies of EGUs, the probability distribution functions (PDFs), which are functions that describe the relative likelihood for the emission factors and energy efficiencies as random variables to take on a given value by the integral of their own probability distributions, are updated using best-fit statistical curves to characterize the uncertainties associated with GHG and CAP emissions in life

  7. The electric vehicle routing problem with non-linear charging functions

    OpenAIRE

    2015-01-01

    International audience; The use of electric vehicles (EVs) in freight and passenger transportation gives birth to a new family of vehicle routing problems (VRPs), the so-called electric VRPs (e-VRPs). As their name suggests, e-VRPs extend classical VRPs to account (mainly) for two constraining EV features: the short driving range and the long battery charging time. As a matter of fact, routes performed by EVs usually need to include time-consuming detours to charging stations. Most of the exi...

  8. Response of the Shockley surface state to an external electrical field: A density-functional theory study of Cu(111)

    Science.gov (United States)

    Berland, K.; Einstein, T. L.; Hyldgaard, P.

    2012-01-01

    The response of the Cu(111) Shockley surface state to an external electrical field is characterized by combining a density-functional theory calculation for a slab geometry with an analysis of the Kohn-Sham wave functions. Our analysis is facilitated by a decoupling of the Kohn-Sham states via a rotation in Hilbert space. We find that the surface state displays isotropic dispersion, quadratic until the Fermi wave vector but with a significant quartic contribution beyond. We calculate the shift in energetic position and effective mass of the surface state for an electrical field perpendicular to the Cu(111) surface; the response is linear over a broad range of field strengths. We find that charge transfer occurs beyond the outermost copper atoms and that accumulation of electrons is responsible for a quarter of the screening of the electrical field. This allows us to provide well converged determinations of the field-induced changes in the surface state for a moderate number of layers in the slab geometry.

  9. Response properties of AgCl and AgBr under an external static electric field: A density functional study

    Science.gov (United States)

    Praveen, C. S.; Kokalj, A.; Rérat, M.; Valant, M.

    2012-10-01

    Density functional theory has been applied to investigate the effect of electric field on the electronic properties of AgCl and AgBr crystals using a static electric field perturbation. A reduction in the band gap value and widening of the band widths are observed with increase in the macroscopic field value indicating a considerable red shift in the absorption spectrum of AgCl and AgBr in the presence of an external electric field. Further, dielectric properties and lattice vibrations at the gamma point are calculated with three different functionals using the CPKS and the Berry phase approach as implemented in CRYSTAL09 code. Finally, the breakdown strength of AgCl and AgBr crystal is evaluated using Callen's equation. In contrast to the case of alkali halides, it is found that the inclusion of the numerically calculated effective mass ratio into the Callen's equation considerably improves the agreement between the calculated dielectric strength and the available experimental datum.

  10. A New Method to Optimize Semiactive Hybrid Energy Storage System for Hybrid Electrical Vehicle by Using PE Function

    Directory of Open Access Journals (Sweden)

    Cong Zhang

    2015-01-01

    Full Text Available Although both battery and super-capacitor are important power sources for hybrid electric vehicles, there is no accurate configuration theory to match the above two kinds of power sources which have significantly different characteristics on energy and power storage for the goal of making good use of their individual features without size wasting. In this paper, a new performance is presented that is used for analysis and optimal design method of battery and super-capacitor for hybrid energy storage system of a parallel hybrid electrical vehicle. In order to achieve optimal design with less consumption, the power-energy function is applied to establish direct mathematical relationship between demand power and the performance. During matching process, firstly, three typical operating conditions are chosen as the basis of design; secondly, the energy and power capacity evaluation methods for the parameters of battery and super-capacitor in hybrid energy storage system are proposed; thirdly, the mass, volume, and cost of the system are optimized simultaneously by using power-energy function. As a result, there are significant advantages on mass, volume, and cost for the hybrid energy storage system with the matching method. Simulation results fit well with the results of analysis, which confirms that the optimized design can meet the demand of hybrid electric vehicle well.

  11. Changes in Work Function and Electrical Resistance of Pt Thin Films in the Presence of Hydrogen Gas

    Science.gov (United States)

    Tsukada, Keiji; Inoue, Hirotsugu; Katayama, Fumiya; Sakai, Kenji; Kiwa, Toshihiko

    2012-01-01

    The changes in the electrical properties, such as work function and resistance, of Pt thin films in the presence of hydrogen gas were studied. They were simultaneously measured with a flow-through cell at different concentrations of hydrogen gas in atmosphere containing gaseous nitrogen and that containing air. The resistance was measured by a four-terminal sensing method and the relative work function changes were measured using a field effect transistor. In both atmospheres, the resistance decreased as the concentration of hydrogen gas increased. This result was repeatable only in air because of the differences in the dynamic mechanism of increased density of electrical carriers inside the Pt film as a result of diffused H atoms. In the nitrogen atmosphere, the diffused H atoms were not easily released because of the surface barrier. On the other hand, oxygen gas reacted with H atoms at the surface and this reaction accelerated atom release into air. The work function showed repeatable responses in both atmospheres, but the response characteristics were different. The equilibrium reaction between the adsorption and desorption of hydrogen occurred at the surface in the nitrogen atmosphere, whereas the equilibrium reaction of hydrogen and oxygen to form water molecules occurred in air. The changes in work function and resistance in the presence of hydrogen were due to changes in dissociated hydrogen intensity in the bulk, as well as to the surface reactions.

  12. Equilibrium-point control of human elbow-joint movement under isometric environment by using multichannel functional electrical stimulation

    Directory of Open Access Journals (Sweden)

    Kazuhiro eMatsui

    2014-06-01

    Full Text Available Functional electrical stimulation (FES is considered an effective technique for aiding quadriplegic persons. However, the human musculoskeletal system has highly nonlinearity and redundancy. It is thus difficult to stably and accurately control limbs using FES. In this paper, we propose a simple FES method that is consistent with the motion-control mechanism observed in humans. We focus on joint motion by a pair of agonist-antagonist muscles of the musculoskeletal system, and define theelectrical agonist-antagonist muscle ratio (EAA ratio and electrical agonist-antagonist muscle activity (EAA activity in light of the agonist-antagonist muscle ratio and agonist-antagonist muscle activity, respectively, to extract the equilibrium point and joint stiffness from electromyography (EMG signals. These notions, the agonist-antagonist muscle ratio and agonist-antagonist muscle activity, are based on the hypothesis that the equilibrium point and stiffness of the agonist-antagonist motion system are controlled by the central nervous system. We derived the transfer function between the input EAA ratio and force output of the end-point. We performed some experiments in an isometric environment using six subjects. This transfer-function model is expressed as a cascade-coupled dead time element and a second-order system. High-speed, high-precision, smooth control of the hand force were achieved through the agonist-antagonist muscle stimulation pattern determined by this transfer function model.

  13. Optical and electrical properties of composites based on functional components of an electroluminescent layer

    Science.gov (United States)

    Avanesyan, V. T.; Rakina, A. V.; Sychov, M. M.; Vasina, E. S.

    2016-07-01

    Optical and electrical properties of cyanoethyl ether of polyvinyl alcohol with filling of barium titanate BaTiO3 modified by shungite carbon nanoparticles are studied. It is found that the modification affects the diffuse reflectance spectra and dispersion characteristics of the impedance components due to a change in the nature of interfacial interactions in the system. The values of the forbidden band width for various modifier and filler concentrations are determined.

  14. Direct electrical control of IgG conformation and functional activity at surfaces

    Science.gov (United States)

    Ghisellini, Paola; Caiazzo, Marialuisa; Alessandrini, Andrea; Eggenhöffner, Roberto; Vassalli, Massimo; Facci, Paolo

    2016-11-01

    We have devised a supramolecular edifice involving His-tagged protein A and antibodies to yield surface immobilized, uniformly oriented, IgG-type, antibody layers with Fab fragments exposed off an electrode surface. We demonstrate here that we can affect the conformation of IgGs, likely pushing/pulling electrostatically Fab fragments towards/from the electrode surface. A potential difference between electrode and solution acts on IgGs’ charged aminoacids modulating the accessibility of the specific recognition regions of Fab fragments by antigens in solution. Consequently, antibody-antigen affinity is affected by the sign of the applied potential: a positive potential enables an effective capture of antigens; a negative one pulls the fragments towards the electrode, where steric hindrance caused by neighboring molecules largely hampers the capture of antigens. Different experimental techniques (electrochemical quartz crystal microbalance, electrochemical impedance spectroscopy, fluorescence confocal microscopy and electrochemical atomic force spectroscopy) were used to evaluate binding kinetics, surface coverage, effect of the applied electric field on IgGs, and role of charged residues on the phenomenon described. These findings expand the concept of electrical control of biological reactions and can be used to gate electrically specific recognition reactions with impact in biosensors, bioactuators, smart biodevices, nanomedicine, and fundamental studies related to chemical reaction kinetics.

  15. The effects of ankle joint muscle strengthening and proprioceptive exercise programs accompanied by functional electrical stimulation on stroke patients' balance.

    Science.gov (United States)

    Kim, Kyunghoon; Lee, Sukmin; Kim, Donghoon; Kim, Kyou Sik

    2015-09-01

    [Purpose] The purpose of the present study was to examine the effects of ankle joint muscle strengthening and proprioceptive exercises accompanied by functional electrical stimulation on stroke patients' balance ability. [Methods] For six weeks beginning in April 2015, 22 stroke patients receiving physical therapy at K Hospital located in Gyeonggi-do were divided into a functional electrical stimulation (FES), ankle proprioceptive exercise and ankle joint muscle strengthening exercise group (FPS group) of 11 patients and an FES and stretching exercise group (FS group) of 11 patients. The stimulation and exercises were conducted for 30 min per day, five days per week for six weeks. Balance ability was measured using a BioRescue and the Berg balance scale, functional reach test, and the timed up-and-go test were also used as clinical evaluation indices. Repeated measures ANOVA was conducted to examine differences between before the exercises and at three and six weeks after beginning the exercises within each group, and the amounts of change between the two groups were compared. [Results] In the comparison within each group, both groups showed significant differences between before and after the experiment in all the tests and comparison between the groups showed that greater improvement was seen in all values in the FPS group. [Conclusion] In the present study, implementing FES and stretching exercises plus ankle joint muscle strengthening and proprioceptive exercises was more effective at improving stroke patients balance ability than implementing only FES and stretching exercises.

  16. Combined arm stretch positioning and neuromuscular electrical stimulation during rehabilitation does not improve range of motion, shoulder pain or function in patients after stroke : a randomised trial

    NARCIS (Netherlands)

    de Jong, Lex D.; Dijkstra, Pieter U.; Gerritsen, Johan; Geurts, Alexander C. H.; Postema, Klaas

    2013-01-01

    Question: Does static stretch positioning combined with simultaneous neuromuscular electrical stimulation (NMES) in the subacute phase after stroke have beneficial effects on basic arm body functions and activities? Design: Multicentre randomised trial with concealed allocation, assessor blinding, a

  17. Combined arm stretch positioning and neuromuscular electrical stimulation during rehabilitation does not improve range of motion, shoulder pain or function in patients after stroke: a randomised trial.

    NARCIS (Netherlands)

    Jong, L.D. de; Dijkstra, P.U.; Gerritsen, J.; Geurts, A.C.H.; Postema, K.

    2013-01-01

    QUESTION: Does static stretch positioning combined with simultaneous neuromuscular electrical stimulation (NMES) in the subacute phase after stroke have beneficial effects on basic arm body functions and activities? DESIGN: Multicentre randomised trial with concealed allocation, assessor blinding, a

  18. Exploring nanoscale electrical and electronic properties of organic and polymeric functional materials by atomic force microscopy based approaches.

    Science.gov (United States)

    Palermo, Vincenzo; Liscio, Andrea; Palma, Matteo; Surin, Mathieu; Lazzaroni, Roberto; Samorì, Paolo

    2007-08-28

    Beyond imaging, atomic force microscopy (AFM) based methodologies enable the quantitative investigation of a variety of physico-chemical properties of (multicomponent) materials with a spatial resolution of a few nanometers. This Feature Article is focused on two AFM modes, i.e. conducting and Kelvin probe force microscopies, which allow the study of electrical and electronic properties of organic thin films, respectively. These nanotools provide a wealth of information on (dynamic) characteristics of tailor-made functional architectures, opening pathways towards their technological application in electronics, catalysis and medicine.

  19. Road load simulator tests of the Gould phase 1 functional model silicon controlled rectifier ac motor controller for electric vehicles

    Science.gov (United States)

    Gourash, F.

    1984-02-01

    The test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator are presented. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

  20. Micro- and nanoscale electrical characterization of large-area graphene transferred to functional substrates

    Directory of Open Access Journals (Sweden)

    Gabriele Fisichella

    2013-04-01

    Full Text Available Chemical vapour deposition (CVD on catalytic metals is one of main approaches for high-quality graphene growth over large areas. However, a subsequent transfer step to an insulating substrate is required in order to use the graphene for electronic applications. This step can severely affect both the structural integrity and the electronic properties of the graphene membrane. In this paper, we investigated the morphological and electrical properties of CVD graphene transferred onto SiO2 and on a polymeric substrate (poly(ethylene-2,6-naphthalene dicarboxylate, briefly PEN, suitable for microelectronics and flexible electronics applications, respectively. The electrical properties (sheet resistance, mobility, carrier density of the transferred graphene as well as the specific contact resistance of metal contacts onto graphene were investigated by using properly designed test patterns. While a sheet resistance Rsh ≈ 1.7 kΩ/sq and a specific contact resistance ρc ≈ 15 kΩ·μm have been measured for graphene transferred onto SiO2, about 2.3× higher Rsh and about 8× higher ρc values were obtained for graphene on PEN. High-resolution current mapping by torsion resonant conductive atomic force microscopy (TRCAFM provided an insight into the nanoscale mechanisms responsible for the very high ρc in the case of graphene on PEN, showing a ca. 10× smaller “effective” area for current injection than in the case of graphene on SiO2.

  1. A microcontroller system for investigating the catch effect: functional electrical stimulation of the common peroneal nerve.

    Science.gov (United States)

    Hart, D J; Taylor, P N; Chappell, P H; Wood, D E

    2006-06-01

    Correction of drop foot in hemiplegic gait is achieved by electrical stimulation of the common peroneal nerve with a series of pulses at a fixed frequency. However, during normal gait, the electromyographic signals from the tibialis anterior muscle indicate that muscle force is not constant but varies during the swing phase. The application of double pulses for the correction of drop foot may enhance the gait by generating greater torque at the ankle and thereby increase the efficiency of the stimulation with reduced fatigue. A flexible controller has been designed around the Odstock Drop Foot Stimulator to deliver different profiles of pulses implementing doublets and optimum series. A peripheral interface controller (PIC) microcontroller with some external circuits has been designed and tested to accommodate six profiles. Preliminary results of the measurements from a normal subject seated in a multi-moment chair (an isometric torque measurement device) indicate that profiles containing doublets and optimum spaced pulses look favourable for clinical use.

  2. Quality Assurance and Functionality Tests on Electrical Components during the ATLAS IBL Production

    CERN Document Server

    Bassalat, A; The ATLAS collaboration

    2014-01-01

    During the shutdown of 2013-2014, for the enhancement of the current ATLAS Pixel Detector, a fourth layer (Insertable B Layer, IBL) is being built and will be installed between the innermost layer and a new beam pipe. A new generation of readout chip has been developed, and two different sensor designs, a rather conventional planar and a 3D design, have been bump bonded to the Front Ends. Additionally, new staves and module flex circuits have been developed. A production QA test bench was therefore established to test all production staves before integration with the new beam pipe. Quality assurance measurements under cleanroom conditions, including temperature and humidity control, are being performed on the individual components during the various production steps of the IBL; namely, connectivity tests, electrical tests and signal probing on individual parts and assembled subsystems. This paper discusses the pre-assembly QC procedures, the capabilities of the stave qualification setup, and recent results fr...

  3. Effect of pulsed electric fields assisted acetylation on morphological, structural and functional characteristics of potato starch.

    Science.gov (United States)

    Hong, Jing; Chen, Rujiao; Zeng, Xin-An; Han, Zhong

    2016-02-01

    Pulsed electric fields (PEF)-assisted acetylation of potato starch with different degree of substitution (DS) was prepared and effects of PEF strength, reaction time, starch concentration on DS were studied by response surface methodology. Results showed DS was increased from 0.054 (reaction time of 15 min) to 0.130 (reaction time of 60 min) as PEF strength increased from 3 to 5 kV/cm. External morphology revealed that acetylated starch with higher DS was aggravated more bulges and asperities. Fourier-transformed infrared spectroscopy confirmed the introduction of acetyl group through a band at 1730 cm(-1). The optimum sample (DS =0 .13) had lower retrogradation (39.1%), breakdown (155 BU) and setback value (149BU), while pasting temperature (62.2 °C) was slightly higher than non-PEF-assisted samples. These results demonstrated PEF treatment can be a potential and beneficial method for acetylation and achieve higher DS with shorter reaction time.

  4. Investigations of electrical and optical properties of functional TCO thin films

    Directory of Open Access Journals (Sweden)

    Domaradzki Jarosław

    2015-06-01

    Full Text Available Transparent conducting oxide (TCO films of indium-tin-oxide were evaporated on the surface of silicon wafers after phosphorous diffusion and on the reference glass substrates. The influence of deposition process parameters (electron beam current, oxygen flow and the substrate temperature on optical and electrical properties of evaporated thin films were investigated by means of resistivity measurements and optical spectrophotometry. The performance of prepared thin films was judged by calculated figure of merit and the best result was obtained for the sample deposited on the substrate heated to the 100 °C and then removed from the deposition chamber and annealed in an air for 5 minutes at 400 °C. Refractive index and extinction coefficient were evaluated based on measured transmission spectra and used for designing of antireflection coating for solar cell. The obtained results showed that prepared TCO thin films are promising as a part of counter electrode in crystalline silicon solar cell construction.

  5. Quality assurance and functionality tests on electrical components during the ATLAS IBL production

    Science.gov (United States)

    Bassalat, A.

    2014-01-01

    During the shutdown of 2013-2014, for the enhancement of the current ATLAS Pixel Detector, a fourth layer (Insertable B Layer, IBL) is being built and will be installed between the innermost layer and a new beam pipe. A new generation of readout chip has been developed, and two different sensor designs, a rather conventional planar and a 3D design, have been bump bonded to the Front Ends. Additionally, new staves and module flex circuits have been developed. A production QA test bench was therefore established to test all production staves before integration with the new beam pipe. Quality assurance measurements under cleanroom conditions, including temperature and humidity control, are being performed on the individual components during the various production steps of the IBL; namely, connectivity tests, electrical tests and signal probing on individual parts and assembled subsystems. This paper discusses the pre-assembly QC procedures, the capabilities of the stave qualification setup, and recent results from stave testing.

  6. Functional electrical stimulation based on a pelvis support robot for gait rehabilitation of hemiplegic patients after stroke.

    Science.gov (United States)

    Ye, Jing; Nakashima, Yasutaka; Zhang, Bo; Kobayashi, Yo; Fujie, Masakatsu G

    2014-01-01

    More and more stroke survivors are suffering from physical motor impairments. Current therapeutic interventions have various limits to the efficient recovery of normal motor function of the lower limbs. Therefore, we propose a novel gait rehabilitation system for hemiplegic patients after stroke. It integrates functional electrical stimulation (FES) with a pelvis-supporting robotic system. A corresponding relationship between the gait phase and the active lateral movement of the pelvis is first constructed from experiments on simulated hemiplegic patients. By estimating the gait phase from the lateral motion of the pelvis based on this relationship, the timing of FES sent to the muscles of the lower limbs can be automatically determined during a gait cycle. After experiments on simulated hemiplegic stroke survivors with the FES control algorithm, the proposed algorithm and the gait rehabilitation system are verified to be feasible and promising.

  7. Therapeutic effects of functional electrical stimulation on gait, motor recovery, and motor cortex in stroke survivors

    Directory of Open Access Journals (Sweden)

    C.V. Shendkar, MTech

    2015-06-01

    Conclusion: FES combined with physiotherapy induced better outcomes in the swing phase of the gait cycle, activation of the affected ankle dorsiflexor muscles and cortical function when compared with conventional physiotherapy alone.

  8. Tooth reorientation affects tooth function during prey processing and tooth ontogeny in the lesser electric ray, Narcine brasiliensis.

    Science.gov (United States)

    Dean, Mason N; Ramsay, Jason B; Schaefer, Justin T

    2008-01-01

    The dental anatomy of elasmobranch fishes (sharks, rays and relatives) creates a functional system that is more dynamic than that of mammalian dentition. Continuous dental replacement (where new teeth are moved rostrally to replace older ones) and indirect fibrous attachment of the dentition to the jaw allow teeth to reorient relative to the jaw over both long- and short-term scales, respectively. In this study, we examine the processing behavior and dental anatomy of the lesser electric ray Narcine brasiliensis (Olfers, 1831) to illustrate that the freedom of movement of elasmobranch dentition allows a functional flexibility that can be important for complex prey processing behaviors. From static manipulations of dissected jaws and observations of feeding events in live animals, we show that the teeth rotate during jaw protrusion, resulting in a secondary grasping mechanism that likely serves to hold prey while the buccal cavity is flushed free of sediment. The function of teeth is not always readily apparent from morphology; in addition to short-term reorientation, the long-term dental reorientation during replacement allows a given tooth to serve multiple functions during tooth ontogeny. Unlike teeth inside the mouth, the cusps of external teeth (on the portion of the tooth pad that extends past the occlusal plane) lay flat, such that the labial faces act as a functional battering surface, protecting the jaws during prey excavation.

  9. Synthesis, characterization and electrical study of new bis-fused tetrathiafulvalenecontains functional groups

    Directory of Open Access Journals (Sweden)

    Meriam Boumedjout

    2015-12-01

    Full Text Available New series of bis-fused tetrathiafulvalene contains functional groups was newly synthesized. The synthesis was carried out by using routes involving cross coupling, reduction, oxidation, and Wittig-type reactions. The identity of these new donors is confirmed by NMR1H, mass spectrometry, and elemental analysis. We have used the cyclic voltammetry in order to determine the character donors-π of these molecules and to verify the reversibility of the redox process involved. Molecular orbital diagram has been calculated using density-functional calculations. Charge transfer complexes with tetraflurotetracyano-quinodimethane (TCNQF4 were prepared by chemical redox reactions.

  10. Rehabilitation of hand in subacute tetraplegic patients based on brain computer interface and functional electrical stimulation: a randomised pilot study

    Science.gov (United States)

    Osuagwu, Bethel C. A.; Wallace, Leslie; Fraser, Mathew; Vuckovic, Aleksandra

    2016-12-01

    Objective. To compare neurological and functional outcomes between two groups of hospitalised patients with subacute tetraplegia. Approach. Seven patients received 20 sessions of brain computer interface (BCI) controlled functional electrical stimulation (FES) while five patients received the same number of sessions of passive FES for both hands. The neurological assessment measures were event related desynchronization (ERD) during movement attempt, Somatosensory evoked potential (SSEP) of the ulnar and median nerve; assessment of hand function involved the range of motion (ROM) of wrist and manual muscle test. Main results. Patients in both groups initially had intense ERD during movement attempt that was not restricted to the sensory-motor cortex. Following the treatment, ERD cortical activity restored towards the activity in able-bodied people in BCI-FES group only, remaining wide-spread in FES group. Likewise, SSEP returned in 3 patients in BCI-FES group, having no changes in FES group. The ROM of the wrist improved in both groups. Muscle strength significantly improved for both hands in BCI-FES group. For FES group, a significant improvement was noticed for right hand flexor muscles only. Significance. Combined BCI-FES therapy results in better neurological recovery and better improvement of muscle strength than FES alone. For spinal cord injured patients, BCI-FES should be considered as a therapeutic tool rather than solely a long-term assistive device for the restoration of a lost function.

  11. Robotics combined with electrical stimulation: hybrid support of arm and hand for functional training after stroke

    NARCIS (Netherlands)

    Westerveld, A.J.

    2014-01-01

    Reach, grasp and release is part of many functional movements. Graying of society leads to more stroke victims and fewer health care professionals. Technology might be a solution to support certain rehabilitation therapies in future health care. Robotic systems have been developed for support of arm

  12. Determination of the functional state of the fruits by parameters of the electric impedance

    Directory of Open Access Journals (Sweden)

    E. V. Guseva

    2014-04-01

    Full Text Available Introduction. To assess the freshness of various products are often used measuring impedance module. But due to the structure of plant foods diagnostic value should have exactly a complex component of impedance. Article tasked with developing criteria for assessing the functional state of the products subject to a comprehensive component of the impedance. Research methodology. To determine the functional status of the fruit were measured module and phase of impedance at the three frequencies of 20, 100 and 500 kHz. Criteria for recognition of functional status deter-mined by the dynamics of changes in the parameters of the complex impedance due to destructive processes caused by dehydration and putrefaction processes. Data processing and analysis. On the basis of experimental data obtained at three frequencies modeled frequency and phase response and their changes during losing of freshness and appear-ance of destructive processes. Discussion and conclusions. In fresh and stale fruit modulus and phase of the impedance at low and high frequencies have characteristic differences. But this is especially evident on the phase–frequency characteristic, which can be seen that the value of the phase with the loss of freshness at low frequency decreases and increases at high more than twice during one week. Therefore, to assess the functional state of fresh and stale products we suggest use phase portraits of phase response.

  13. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    OpenAIRE

    Carmel, Jason B; John eMartin

    2014-01-01

    The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST) – is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-d...

  14. The need for seasonal correction functions when calculating the annual electricity use of appliances based on shorter period measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bennich, Peter (Testlab, The Swedish Energy Agency, Eskilstuna (Sweden)); Oefverholm, Egil; Bjoern, Torgny (The Swedish Energy Agency, Eskilstuna (Sweden)); Norstedt, Inger (The Swedish Consumer Agency, Stockholm (Sweden))

    2011-07-01

    Along with the increasing number of smart electricity meters in the homes - both meters installed by the utilities and simpler ones installed by the household owners themselves - the interest in reliable methods for scaling up data measured during a limited time of the year to annual values, will most likely increase. For example, by measuring some specific loads for some time in a home, an inhabitant may assess possible annual savings when replacing old appliances with new ones. However, a straight forward scaling up calculation to annual values is not always appropriate. An obvious example is lighting, which displays a clear seasonal effect due to the difference in daylight: annual values based on measured summer data will strongly underestimate the annual consumption whereas winter data will lead to an overestimate. Another example going in the opposite direction is cold appliances, where the increase in ambient temperature during the summer increases the electricity consumption. This paper discusses an analysis of a set of appliances which nearly all display different seasonal effects. Apart from lighting and cold appliances, also washing machines, dish washers, TVs and PCs are analysed. Factors influencing the seasonality are discussed; either it is due to behaviour and/or technical parameters as well. Our analysis is based on 10 min measurements of appliances in 400 randomly selected households in Sweden. 40 households were measured during a full year and provided data for establishing seasonal correction functions. (See Appendix 1 for more details on the methodology.)

  15. A self-adaptive foot-drop corrector using functional electrical stimulation (FES) modulated by tibialis anterior electromyography (EMG) dataset.

    Science.gov (United States)

    Chen, Mo; Wu, Bian; Lou, Xinxin; Zhao, Ting; Li, Jianhua; Xu, Zhisheng; Hu, Xiaoling; Zheng, Xiaoxiang

    2013-02-01

    We developed a functional electrical stimulator for correcting the gait patterns of patients with foot-drop problem. The stimulating electrical pulses of the system are modulated to evoke contractions of the tibialis anterior muscle, by emulating the normal patterns. The modulation is adaptive, i.e. the system can predict the user's step frequency and the generated stimulation can match each step in real-time. In this study, step data from 11 young healthy volunteers were acquired, and five prediction algorithms were evaluated by the acquired data, including the average of Previous N steps (P-N), the Previous Nth step (P-Nth), General Regression Neural Network (GRNN), Autoregressive (AR) and Kalman filter (KF). The algorithm with the best efficiency-accuracy trade-off (P-N, when N=5) was implemented in the FES system. System evaluation results obtained from a post-stroke patient with foot-drop showed that the system of this study demonstrated better performance on gait pattern correction than the methods widely adopted in commercial products.

  16. Using CPE Function to Size Capacitor Storage for Electric Vehicles and Quantifying Battery Degradation during Different Driving Cycles

    Directory of Open Access Journals (Sweden)

    Cong Zhang

    2016-11-01

    Full Text Available Range anxiety and battery cycle life are two major factors which restrict the development of electric vehicles. Battery degradation can be reduced by adding supercapacitors to create a Hybrid Energy Storage System. This paper proposes a systematic approach to configure the hybrid energy storage system and quantifies the battery degradation for electric vehicles when using supercapacitors. A continuous power-energy function is proposed to establish supercapacitor size based on national household travel survey statistics. By analyzing continuous driving action in standard driving cycles and special driving phases (start up and acceleration, the supercapacitor size is calculated to provide a compromise between the capacitor size and battery degradation. Estimating the battery degradation after 10 years, the battery capacity loss value decreases 17.55% and 21.6%, respectively, under the urban dynamometer driving schedule and the US06. Furthermore, the battery lifespan of the continuous power-energy configured system is prolonged 28.62% and 31.39%, respectively, compared with the battery alone system.

  17. The effect of dispersion status with functionalized graphenes for electric double-layer capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.-R., E-mail: d98527015@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd, Taipei 10617, Taiwan (China); Department of Materials Science and Engineering, Feng Chia University, 100 Wen Hwa Rd, 407 Taichung, Taiwan (China); Chiu, K.-F. [Department of Materials Science and Engineering, Feng Chia University, 100 Wen Hwa Rd, 407 Taichung, Taiwan (China); Lin, H.C. [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd, Taipei 10617, Taiwan (China); Hsieh, C.-Y. [Enerage Inc., No. 5, Ligong 3rd Rd, Wujie Township, Yilan County 26841, Taiwan (China); Tsai, C.B. [Taiwan Textile Research Institute, No. 6, Chengtian Rd, Tucheng City, Taipei 23674, Taiwan (China); Chu, B.T.T. [Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, 8600 Dübendorf (Switzerland)

    2014-12-15

    Highlights: • MrGO/NMP can reduce the IR drops and R{sub ct} of the supercapacitors. • M-rGO can provide excellent plane-to-point conducting network. • M-rGO can effectively enhance high rate performance of supercapacitors. • M-rGO additive can deliver high capacity under high rate cycling. - Abstract: Graphene with oxygen (M-rGO and H-rGO) and nitrogen (N-rGO) related functional groups have been fabricated. Reduced graphenes including H-rGO, M-rGO and N-rGO were mixed with activated carbons as the composite electrodes and characterized for supercapacitors. The effects of the functional groups on graphenes as the conductive additive have been investigated. It was found that a suitable content of functional groups can improve the stability of dispersion, and therefore reduce the internal resistance (IR drop) and charge transfer resistance (R{sub ct}) resulting in higher rate capability. The supercapacitor with M-rGO and KS6 as additive at the activated carbon electrode can be operated at a rate as high as 6 A/g and exhibits a capacitance of 208 F/g, whereas the supercapacitor using only KS6 as additive shows a capacitance of only 107 F/g. The graphene contained supercapacitor has been cycled over 2000 times at 4 A/g with almost no capacitance fading.

  18. Electric dipole moment function of the X1 Sigma/+/ state of CO - Vibration-rotation matrix elements for transitions of gas laser and astrophysical interest

    Science.gov (United States)

    Chackerian, C., Jr.

    1976-01-01

    The electric dipole moment function of the ground electronic state of carbon monoxide has been determined by combining numerical solutions of the radial Schrodinger equation with absolute intensity data of vibration-rotation bands. The derived dipole moment function is used to calculate matrix elements of interest to stellar astronomy and of importance in the carbon monoxide laser.

  19. Brain-computer interface driven functional electrical stimulation system for overground walking in spinal cord injury participant.

    Science.gov (United States)

    King, Christine E; Wang, Po T; McCrimmon, Colin M; Chou, Cathy C Y; Do, An H; Nenadic, Zoran

    2014-01-01

    The current treatment for ambulation after spinal cord injury (SCI) is to substitute the lost behavior with a wheelchair; however, this can result in many co-morbidities. Thus, novel solutions for the restoration of walking, such as brain-computer interfaces (BCI) and functional electrical stimulation (FES) devices, have been sought. This study reports on the first electroencephalogram (EEG) based BCI-FES system for overground walking, and its performance assessment in an individual with paraplegia due to SCI. The results revealed that the participant was able to purposefully operate the system continuously in real time. If tested in a larger population of SCI individuals, this system may pave the way for the restoration of overground walking after SCI.

  20. Multi-functional Converter with Integrated Motor Control, Battery Charging and Active Module Balancing for Electric Vehicular Application

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Schaltz, Erik; Teodorescu, Remus

    2014-01-01

    , weight and volume in comparison with other Li-Ion based chemistries. The control of the energy flow has been done through a Modular Multilevel Converter (MMC), which has demonstrated advantages over 2 level converters in terms of efficiency, fault tolerant operation, flexible operation modes. It has been......In order to reduce the fuel consumption and the acoustical noise generated by refuse lorries, electrification of the waste compactor unit is a very promising solution. For the electrical energy storage Lithium-Sulfur (Li-S) battery technology has been selected with potential for reducing the cost...... used successfully in HVDC/FACTS and large drive applications. In this paper the use of MMC for a battery driven waste compactor unit addressed with integrated functionality including: motor driver, battery charge and active balancing is presented. The challenges addressed here are related to the design...

  1. Design and application of electric oil pump in automatic transmission for efficiency improvement and start–stop function

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-fang; DONG Peng; LIU Yang; XU Xiang-yang

    2016-01-01

    For the purpose of improving efficiency and realizing start–stop function, an electric oil pump (EOP) is integrated into an 8-speed automatic transmission (AT). A mathematical model is built to calculate the transmission power loss and the hydraulic system leakage. Based on this model, a flow-based control strategy is developed for EOP to satisfy the system flow requirement. This control strategy is verified through the forward driving simulation. The results indicate that there is a best combination for the size of mechanical oil pump (MOP) and EOP in terms of minimum energy consumption. In order to get a quick and smooth starting process, control strategies of the EOP and the on-coming clutch are proposed. The test environment on a prototype vehicle is built to verify the feasibility of the integrated EOP and its control strategies. The results show that the selected EOP can satisfy the flow requirement and a quick and smooth starting performance is achieved in the start–stop function. This research has a high value for the forward design of EOP in automatic transmissions with respect to efficiency improvement and start–stop function.

  2. Effects of preoperative neuromuscular electrical stimulation on quadriceps strength and functional recovery in total knee arthroplasty. A pilot study

    Directory of Open Access Journals (Sweden)

    O'Gorman Donal J

    2010-06-01

    Full Text Available Abstract Background Supervised preoperative muscle strengthening programmes (prehabilitation can improve recovery after total joint arthroplasty but are considered resource intensive. Neuromuscular electrical stimulation (NMES has been shown to improve quadriceps femoris muscle (QFM strength and clinical function in subjects with knee osteoarthritis (OA however it has not been previously investigated as a prehabilitation modality. Methods This pilot study assessed the compliance of a home-based, NMES prehabilitation programme in patients undergoing total knee arthroplasty (TKA. We evaluated its effect on preoperative and postoperative isometric quadriceps femoris muscle (QFM strength, QFM cross-sectional area (CSA and clinical function (subjective and objective. Seventeen subjects were recruited with 14 completing the study (NMES group n = 9; Control group n = 5. Results Overall compliance with the programme was excellent (99%. Preoperative QFM strength increased by 28% (p > 0.05 with associated gains in walk, stair-climb and chair-rise times (p 0.05 at 12 weeks postoperatively compared to baseline. There were only limited associations found between objective and subjective functional outcome instruments. Conclusions This pilot study has shown that preoperative NMES may improve recovery of quadriceps muscle strength and expedite a return to normal activities in patients undergoing TKA for OA. Recommendations for appropriate outcome instruments in future studies of prehabilitation in TKA have been provided.

  3. Upper-limb stroke rehabilitation using electrode-array based functional electrical stimulation with sensing and control innovations.

    Science.gov (United States)

    Kutlu, M; Freeman, C T; Hallewell, E; Hughes, A-M; Laila, D S

    2016-04-01

    Functional electrical stimulation (FES) has shown effectiveness in restoring upper-limb movement post-stroke when applied to assist participants' voluntary intention during repeated, motivating tasks. Recent clinical trials have used advanced controllers that precisely adjust FES to assist functional reach and grasp tasks with FES applied to three muscle groups, showing significant reduction in impairment. The system reported in this paper advances the state-of-the-art by: (1) integrating an FES electrode array on the forearm to assist complex hand and wrist gestures; (2) utilising non-contact depth cameras to accurately record the arm, hand and wrist position in 3D; and (3) employing an interactive touch table to present motivating virtual reality (VR) tasks. The system also uses iterative learning control (ILC), a model-based control strategy which adjusts the applied FES based on the tracking error recorded on previous task attempts. Feasibility of the system has been evaluated in experimental trials with 2 unimpaired participants and clinical trials with 4 hemiparetic, chronic stroke participants. The stroke participants attended 17, 1 hour training sessions in which they performed functional tasks, such as button pressing using the touch table and closing a drawer. Stroke participant results show that the joint angle error norm reduced by an average of 50.3% over 6 attempts at each task when assisted by FES.

  4. Single session of brief electrical stimulation immediately following crush injury enhances functional recovery of rat facial nerve

    Directory of Open Access Journals (Sweden)

    Eileen M. Foecking, PhD

    2012-04-01

    Full Text Available Peripheral nerve injuries lead to a variety of pathological conditions, including paresis or paralysis when the injury involves motor axons. We have been studying ways to enhance the regeneration of peripheral nerves using daily electrical stimulation (ES following a facial nerve crush injury. In our previous studies, ES was not initiated until 24 h after injury. The current experiment tested whether ES administered immediately following the crush injury would further decrease the time for complete recovery from facial paralysis. Rats received a unilateral facial nerve crush injury and an electrode was positioned on the nerve proximal to the crush site. Animals received daily 30 min sessions of ES for 1 d (day of injury only, 2 d, 4 d, 7 d, or daily until complete functional recovery. Untreated animals received no ES. Animals were observed daily for the return of facial function. Our findings demonstrated that one session of ES was as effective as daily stimulation at enhancing the recovery of most functional parameters. Therefore, the use of a single 30 min session of ES as a possible treatment strategy should be studied in human patients with paralysis as a result of acute nerve injuries.

  5. The Development of control system via Brain Computer Interface (BCI - Functional Electrical Stimulation (FES for paraplegic subject

    Directory of Open Access Journals (Sweden)

    K. A. A. Rahman

    2012-12-01

    Full Text Available Brain is known to be one of the powerful systems in human body because of its ability to give command and communicate throughout the body. The spinal cord is the pathway for impulses from the brain to the body as well as from the body to the brain. However, the bounty of this pathway could be lost due to spinal cord injury (SCI and that results in a loss of function especially mobility. A combination of Brain Computer Interface (BCI and Functional Electrical Stimulation (FES is among one of the technique to regain the mobility function of human body which will be the focused area of this research. In this study, Electroencephalography (EEG system will be used to capture the brain signal which will then drive the FES. A paraplegic subject will be involved in this study. The subject will be required to move the knee joint with involvement few muscle contraction. Overall, in this paper the combination of BCI-FES methods for development of rehabilitation system will be proposed. From this preliminary study, it can be summarized that the combination between BCI and FES potentially would provide a better rehabilitation system for SCI patient in comparison to the conventional FES system.

  6. Developmental changes in fact and source recall: Contributions from executive function and brain electrical activity

    Directory of Open Access Journals (Sweden)

    Vinaya Rajan

    2015-04-01

    Full Text Available Source memory involves recollecting the contextual details surrounding a memory episode. When source information is bound together, it makes a memory episodic in nature. Unfortunately, very little is known about the factors that contribute to its formation in early development. This study examined the development of source memory in middle childhood. Measures of executive function were examined as potential sources of variation in fact and source recall. Continuous electroencephalogram (EEG measures were collected during baseline and fact and source retrieval in order to examine memory-related changes in EEG power. Six and 8-year-old children were taught 10 novel facts from two different sources and recall for fact and source information was later tested. Older children were better on fact recall, but both ages were comparable on source recall. However, source recall performance was poor at both ages, suggesting that this ability continues to develop beyond middle childhood. Regression analyses revealed that executive function uniquely predicted variance in source recall performance. Task-related increases in theta power were observed at frontal, temporal and parietal electrode sites during fact and source retrieval. This investigation contributes to our understanding of age-related differences in source memory processing in middle childhood.

  7. High resolution functional photoacoustic computed tomography of the mouse brain during electrical stimulation

    Science.gov (United States)

    Avanaki, Mohammad R. N.; Xia, Jun; Wang, Lihong V.

    2013-03-01

    Photoacoustic computed tomography (PACT) is an emerging imaging technique which is based on the acoustic detection of optical absorption from tissue chromophores, such as oxy-hemoglobin and deoxy-hemoglobin. An important application of PACT is functional brain imaging of small animals. The conversion of light to acoustic waves allows PACT to provide high resolution images of cortical vasculatures through the intact scalp. Here, PACT was utilized to study the activated areas of the mouse brain during forepaw and hindpaw stimulations. Temporal PACT images were acquired enabling computation of hemodynamic changes during stimulation. The stimulations were performed by trains of pulses at different stimulation currents (between 0.1 to 2 mA) and pulse repetition rates (between 0.05 Hz to 0.01Hz). The response at somatosensory cortex-forelimb, and somatosensory cortex-hindlimb, were investigated. The Paxinos mouse brain atlas was used to confirm the activated regions. The study shows that PACT is a promising new technology that can be used to study brain functionality with high spatial resolution.

  8. A modular function architecture for adaptive and predictive energy management in hybrid electric vehicles; Eine modulare Funktionsarchitektur fuer adaptives und vorausschauendes Energiemanagement in Hybridfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, Andreas

    2009-10-27

    Due to the relatively low energy density of electrical energy storage devices, the control strategy of hybrid electric vehicles has to fulfil a variety of requirements in order to provide both, the availability of hybrid functions, and their efficient execution. Energy consuming functions such as electric drive or electric boost need a high amount of energy stored in the battery. On the other hand for the optimum use of the energy regeneration function a lower state of charge is preferable in order to enable storage of the kinetic energy of the vehicle in all situations, including upon deceleration from high speeds or downhill driving. These diverging requirements yield a conflict of objectives for the charging strategy of hybrid electric vehicles. This work proposes a way to overcome the restrictions on efficiency in hybrid electric vehicles without deteriorating overall driving performance by charging or discharging the traction battery, and by setting the energy management parametres according to the current and forthcoming driving situation. Specific charging and electric drive strategies are presented for various driving situations which are identified by sensors such as navigation systems, cameras or radar. Necessary sensor data fusion methods for driving situation identification are described and a modular function architecture for predictive energy management is derived that is plug-and-play compatible with a broad fleet of vehicles. In order to evaluate its potential, this work also focuses on the simulation of the energy functions and their implementation into an experimental vehicle. This allows measurements under real traffic conditions and a sensivity analysis of the main module interactions within the architecture. (orig.)

  9. Comparison of muscle functional electrical stimulation to conventional bicycle exercise on endothelium and functional status indices in patients with heart failure.

    Science.gov (United States)

    Deftereos, Spyridon; Giannopoulos, Georgios; Raisakis, Konstantinos; Kossyvakis, Charalampos; Kaoukis, Andreas; Driva, Metaxia; Pappas, Loukas; Panagopoulou, Vasiliki; Ntzouvara, Olga; Karavidas, Apostolos; Pyrgakis, Vlasios; Rentoukas, Ilias; Aggeli, Constadina; Stefanadis, Christodoulos

    2010-12-01

    The aim of this prospective, open-label, cohort study was to compare the effect of muscle functional electrical stimulation (FES) on endothelial function to that of conventional bicycle training. Eligible patients were those with New York Heart Association class II or III heart failure symptoms and ejection fractions ≤ 0.35. Two physical conditioning programs were delivered: FES of the muscles of the lower limbs and bicycle training, each lasting for 6 weeks, with a 6-week washout period between them. Brachial artery flow-mediated dilation (FMD) and other parameters were assessed before and after FES and the bicycle training program. FES resulted in a significant improvement in FMD, which increased from 5.9 ± 0.5% to 7.7 ± 0.5% (95% confidence interval for the difference 1.5% to 2.3%, p Bicycle training also resulted in a substantial improvement of endothelial function. FMD increased from 6.2 ± 0.4% to 9.2 ± 0.4% (95% confidence interval for the difference 2.5% to 3.5%, p bicycle exercise (95% confidence interval for the difference between the relative changes 1.2% to 30.5%, p = 0.034). This resulted in attaining a significantly higher FMD value after bicycle training compared to FES (9.2 ± 0.4% vs 7.7 ± 0.5%, p < 0.001). In conclusion, the effect of muscle FES in patients with heart failure on endothelial function, although not equivalent to that of conventional exercise, is substantial. Muscle FES protocols may prove very useful in the treatment of patients with heart failure who cannot or will not adhere to conventional exercise programs.

  10. Experimental Determination of the 1 Sigma(+) State Electric-Dipole-Moment Function of Carbon Monoxide up to a Large Internuclear Separation

    Science.gov (United States)

    Chackerian, C., Jr.; Farreng, R.; Guelachvili, G.; Rossetti, C.; Urban, W.

    1984-01-01

    Experimental intensity information is combined with numerically obtained vibrational wave functions in a nonlinear least squares fitting procedure to obtain the ground electronic state electric-dipole-moment function of carbon monoxide valid in the range of nuclear oscillation (0.87 to 1.01 A) of about the V = 38th vibrational level. Mechanical anharmonicity intensity factors, H, are computed from this function for delta V + = 1, 2, 3, with or = to 38.

  11. Measurement of the Electric and Magnetic Elastic Structure Functions of the Deuteron at Large Momentum Transfers

    Energy Technology Data Exchange (ETDEWEB)

    Riad Suleiman

    1999-10-01

    The deuteron elastic structure functions, A(Q{sup 2}) and B(Q{sup 2}), have been extracted from cross section measurements of elastic electron-deuteron scattering in coincidence using the Continuous Electron Beam Accelerator and Hall A Facilities of Jefferson Laboratory. Incident electrons were scattered off a high-power cryogenic deuterium target. Scattered electrons and recoil deuterons were detected in the two High Resolution Spectrometers of Hall A. A(Q{sup 2}) was extracted from forward angle cross section measurements in the squared four-momentum transfer range 0.684 ≤ Q{sup 2} ≤ 5.90 (GeV/c){sup 2}. B(Q{sup 2}) was determined by means of a Rosenbluth separation in the range 0.684 ≤ Q{sup 2} ≤ 1.325 (GeV/c){sup 2}. The data are compared to theoretical models based on the impulse approximation with the inclusion of meson-exchange currents and to predictions of quark dimensional scaling and perturbative quantum chromodynamics. The results are expected to provide insights into the transition from meson-nucleon to quark-gluon descriptions of the nuclear two-body system.

  12. Functional electrical stimulation: a MatLab based tool for designing stimulation patterns.

    Science.gov (United States)

    Dosen, Strahinja; Popović, Dejan B

    2006-01-01

    We developed user-friendly software that generates stimulation profiles by using user-customized model-based control of walking. The model is a multi-segment structure with pin and ball joints. A pair of an agonist and an antagonistic muscles acts at each joint. Each muscle is modeled by a three-compartment multiplicative model. The control is based on optimization that uses a cost function that minimizes the tracking error of the joint angles and levels of muscles activations. The inputs to the simulation are trajectories and user characteristic model parameters. The outputs of the simulation are levels of muscle activations vs. time. The software allows for interactive testing of various walking trajectories and model parameters since the simulation is integrated into a database of individuals and reference trajectories. The simulation was realized in the MatLab environment with multiple windows graphical user interface. Here we present an example: stimulation patterns for the shank-foot system that is applicable for walking control in hemiplegic individuals.

  13. Spatial and temporal heterogeneity of regional lung ventilation determined by electrical impedance tomography during pulmonary function testing.

    Science.gov (United States)

    Vogt, Barbara; Pulletz, Sven; Elke, Gunnar; Zhao, Zhanqi; Zabel, Peter; Weiler, Norbert; Frerichs, Inéz

    2012-10-01

    Electrical impedance tomography (EIT) is a functional imaging modality capable of tracing continuously regional pulmonary gas volume changes. The aim of our study was to determine if EIT was able to assess spatial and temporal heterogeneity of ventilation during pulmonary function testing in 14 young (37 ± 10 yr, mean age ± SD) and 12 elderly (71 ± 9 yr) subjects without lung disease and in 33 patients with chronic obstructive pulmonary disease (71 ± 9 yr). EIT and spirometry examinations were performed during tidal breathing and a forced vital capacity (FVC) maneuver preceded by full inspiration to total lung capacity. Regional inspiratory vital capacity (IVC); FVC; forced expiratory volume in 1 s (FEV(1)); FEV(1)/FVC; times required to expire 25%, 50%, 75%, and 90% of FVC (t(25), t(50), t(75), t(90)); and tidal volume (V(T)) were determined in 912 EIT image pixels in the chest cross section. Coefficients of variation (CV) were calculated from all pixel values of IVC, FVC, FEV(1), and V(T) to characterize the ventilation heterogeneity. The highest values were found in patients, and no differences existed between the healthy young and elderly subjects. Receiver-operating characteristics curves showed that CV of regional IVC, FVC, FEV(1), and V(T) discriminated the young and elderly subjects from the patients. Frequency distributions of pixel FEV(1)/FVC, t(25), t(50), t(75), and t(90) identified the highest ventilation heterogeneity in patients but distinguished also the healthy young from the elderly subjects. These results indicate that EIT may provide additional information during pulmonary function testing and identify pathologic and age-related spatial and temporal heterogeneity of regional lung function.

  14. The gravitational field and brain function

    Science.gov (United States)

    Mei, Lei; Zhou, Chuan-Dai; Lan, Jing-Quan; Wang, Zhi-Ging; Wu, Wen-Can; Xue, Xin-Min

    The frontal cortex is recognized as the highest adaptive control center of the human brain. The principle of the ``frontalization'' of human brain function offers new possibilities for brain research in space. There is evolutionary and experimental evidence indicating the validity of the principle, including it's role in nervous response to gravitational stimulation. The gravitational field is considered here as one of the more constant and comprehensive factors acting on brain evolution, which has undergone some successive crucial steps: ``encephalization'', ``corticalization'', ``lateralization'' and ``frontalization''. The dominating effects of electrical responses from the frontal cortex have been discovered 1) in experiments under gravitational stimulus; and 2) in processes potentially relating to gravitational adaptation, such as memory and learning, sensory information processing, motor programing, and brain state control. A brain research experiment during space flight is suggested to test the role of the frontal cortex in space adaptation and it's potentiality in brain control.

  15. Towards a functional topography of sensory gating areas: invasive P50 recording and electrical stimulation mapping in epilepsy surgery candidates.

    Science.gov (United States)

    Kurthen, Martin; Trautner, Peter; Rosburg, Timm; Grunwald, Thomas; Dietl, Thomas; Kühn, Kai-Uwe; Schaller, Carlo; Elger, Christian E; Urbach, Horst; Elisevich, Kost; Boutros, Nash N

    2007-07-15

    The filtering of sensory information, also referred to as "sensory gating", is impaired in various neuropsychiatric diseases. In the auditory domain, sensory gating is investigated mainly as a response decrease of the auditory evoked potential component P50 from one click to the second in a double-click paradigm. In order to relate deficient sensory gating to anatomy, it is essential to identify the cortical structures involved in the generation of P50. However, the exact cerebral topography of P50 gating remains largely unknown. In a group of 17 patients with drug-resistant focal epilepsy, P50 was recorded invasively via subdural electrodes, and the topography of functionally indispensable ("eloquent") cortices was obtained by electrical stimulation mapping. These eloquent areas were involved in language, motor, and sensory functions. P50 could be identified in 13 patients in either temporal (n=8) or midfrontal sites (n=5). There were six occurrences (in five patients) of overlap of sites with maximal P50 responses and eloquent areas. Those were auditory (n=1), supplementary sensorimotor (n=3), primary motor (n=1), and supplementary negative motor (n=1). Results suggest that the early stage of sensory gating already involves a top-down modulation of sensory input by frontal areas.

  16. Design and Control of a Multi-Functional Energy Recovery Power Accumulator Battery Pack Testing System for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Bo Long

    2014-03-01

    Full Text Available In this paper, aiming at the energy loss and harmonic problems in the conventional power accumulator battery pack testing system (PABPTS, an improved multi-functional energy recovery PABPTS (ERPABPTS for electric vehicles (EVs was proposed. The improved system has the functions of harmonic detection, suppression, reactive compensation and energy recovery. The ERPABPTS, which contains a bi-directional buck-boost direct current (DC-DC converter and a bi-directional alternating current (AC-DC converter with an inductor-capacitor-inductor (LCL type filter interfacing to the AC-grid, is proposed. System configuration and operation principle of the combined system are discussed first, then, the reactive compensation and harmonic suppression controller under balanced grid-voltage condition are presented. Design of a fourth order band-pass Butterworth filter for current harmonic detection is put forward, and the reactive compensator design procedure considering the non-linear load is also illustrated. The proposed scheme is implemented in a 175-kW prototype in the laboratory. Simulation and experimental results show that the combined configuration can effectively realize energy recovery for high accuracy current test requirement, meanwhile, can effectively achieve reactive compensation and current harmonic suppression.

  17. Propagation of Surface Waves in a Homogeneous Layer of Finite Thickness over an Initially Stressed Functionally Graded Magnetic-Electric-Elastic Half-Space

    Directory of Open Access Journals (Sweden)

    Li Li

    2015-03-01

    Full Text Available The propagation behaviour of Love wave in an initially stressed functionally graded magnetic-electric-elastic half-space carrying a homogeneous layer is investigated. The material parameters in the substrate are assumed to vary exponentially along the thickness direction only. The velocity equations of Love wave are derived on the electrically or magnetically open circuit and short circuit boundary conditions, based on the equations of motion of the graded magnetic-electric-elastic mate- rial with the initial stresses and the free traction boundary conditions of surface and the continuous boundary conditions of interface. The dispersive curves are obtained numerically and the influences of the initial stresses and the material gradient index on the dispersive curves are dis- cussed. The investigation provides a basis for the development of new functionally graded magneto-electro-elastic surface wave devices.

  18. Polarized fluorescence in an electric field: steady state and transient values for the fourth moment of the orientation function at arbitrary fields.

    Science.gov (United States)

    Sokerov, S; Weill, G

    1979-07-01

    Steady state and time dependent expressions for the field dependence of the fourth moment of the orientation function at arbitrary fields, which are requested for the interpretation of polarisation of fluorescence in an electric field, have been obtained for permanent and induced dipole orientation. Some general features of the results and some problems connected with their application are pointed out.

  19. Highly electrically conductive layered carbon derived from polydopamine and its functions in SnO2-based lithium ion battery anodes.

    Science.gov (United States)

    Kong, Junhua; Yee, Wu Aik; Yang, Liping; Wei, Yuefan; Phua, Si Lei; Ong, Hock Guan; Ang, Jia Ming; Li, Xu; Lu, Xuehong

    2012-10-25

    Thin carbonized polydopamine (C-PDA) coatings are found to have similar structures and electrical conductivities to those of multilayered graphene doped with heteroatoms. Greatly enhanced electrochemical properties are achieved with C-PDA-coated SnO(2) nanoparticles where the coating functions as a mechanical buffer layer and conducting bridge.

  20. Response of the Shockley surface state on Cu(111) to an external electrical field: A density-functional theory study

    Science.gov (United States)

    Berland, Kristian; Hyldgaard, Per; Einstein, T. L.

    2011-03-01

    We study the response of the Cu(111) Shockley surface state to an external electrical field E by combining a density-functional theory calculation for a finite slab geometry with an analysis of the Kohn-Sham wavefunctions to obtain a well-converged characterization. We find that the surface state displays isotropic dispersion, quadratic until the Fermi wave vector but with a significant quartic contribution beyond. We find that the shift in band minimum and effective mass depend linearly on E. Most change in electrostatic potential profile, and charge transfer occurs outside the outermost copper atoms, and most of the screening is due to bulk electrons. Our analysis is facilitated by a method used to decouple the Kohn-Sham states due to the finite slab geometry, using a rotation in Hilbert space. We discuss applications to tuning the Fermi wavelength and so the many patterns attributed to metallic surface states. Supported by (KB and PH) Swedish Vetenskapsrådet VR 621-2008-4346 and (TLE) NSF CHE 07-50334 & UMD MRSEC DMR 05-20471.

  1. Myoelectrically driven functional electrical stimulation may increase motor recovery of upper limb in poststroke subjects: A randomized controlled pilot study

    Directory of Open Access Journals (Sweden)

    Rune Thorsen, PhD, MScee

    2013-08-01

    Full Text Available The objective of this randomized controlled pilot study was to assess the feasibility and effectiveness of myoelectrically controlled functional electrical stimulation (MeCFES for rehabilitation of the upper limb in poststroke subjects. Eleven poststroke hemiparetic subjects with residual proximal control of the arm, but impaired volitional opening of the paretic hand, were enrolled and randomized into a treated and a control group. Subjects received 3 to 5 treatment sessions per week until totaling 25 sessions. In the experimental group, myoelectric activity from wrist and finger extensors was used to control stimulation of the same muscles. Patients treated with MeCFES (n = 5 had a significant (p = 0.04 and clinically important improvement in Action Research Arm Test score (median change 9 points, confirmed by an Individually Prioritized Problem Assessment self-evaluation score. This improvement was maintained at follow-up. The control group did not show a significant improvement (p = 0.13. The reduced sample size of participants, together with confounding factors such as spontaneous recovery, calls for larger studies to draw definite conclusions. However, the large and persistent treatment effect seen in our results indicate that MeCFES could play an important role as a clinical tool for stroke rehabilitation.

  2. Tuning the Electrical Memory Behavior from Nonvolatile to Volatile in Functional Copolyimides Bearing Varied Fluorene and Pyrene Moieties

    Science.gov (United States)

    Jia, Nanfang; Qi, Shengli; Tian, Guofeng; Wang, Xiaodong; Wu, Dezhen

    2017-04-01

    For producing polymer based electronics with good memory behavior, a series of functional copolyimides were designed and synthesized in this work by copolymerizing 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride (DSDA) with (9,9'-bis(4-aminophenyl)fluorene) (BAPF) and N, N-bis(4-aminophenyl) aminopyrene (DAPAP) diamines. The synthesized copolyimides DSDA/(DAPAP/BAPF) were denoted as coPI-DAPAP x ( x = 100, 50, 20, 10, 5, 1, 0), where x% represents the molar fraction of the DAPAP unit in the diamines. Characterization results indicate that the coPI-DAPAP x exhibits tunable electrical switching behaviors from write once read many times (WORM, nonvolatile, coPI-DAPAP100, coPI-DAPAP50, coPI-DAPAP20, coPI-DAPAP10) to the static random access memory (SRAM, volatile, coPI-DAPAP5, coPI-DAPAP1) with the variation of the DAPAP content. Optical and electrochemical characterization show gradually decreasing highest occupied molecular orbital levels and enlarged energy gap with the decrease of the DAPAP moiety, suggesting decreasing charge-transfer effect in the copolyimides, which can account for the observed WORM-SRAM memory conversion. Meanwhile, the charge transfer process was elucidated by quantum chemical calculation at B3LYP/6-31G(d) theory level. This work shows the effect of electron donor content on the memory behavior of polymer electronic materials.

  3. Tuning the Electrical Memory Behavior from Nonvolatile to Volatile in Functional Copolyimides Bearing Varied Fluorene and Pyrene Moieties

    Science.gov (United States)

    Jia, Nanfang; Qi, Shengli; Tian, Guofeng; Wang, Xiaodong; Wu, Dezhen

    2016-12-01

    For producing polymer based electronics with good memory behavior, a series of functional copolyimides were designed and synthesized in this work by copolymerizing 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride (DSDA) with (9,9'-bis(4-aminophenyl)fluorene) (BAPF) and N,N-bis(4-aminophenyl) aminopyrene (DAPAP) diamines. The synthesized copolyimides DSDA/(DAPAP/BAPF) were denoted as coPI-DAPAPx (x = 100, 50, 20, 10, 5, 1, 0), where x% represents the molar fraction of the DAPAP unit in the diamines. Characterization results indicate that the coPI-DAPAPx exhibits tunable electrical switching behaviors from write once read many times (WORM, nonvolatile, coPI-DAPAP100, coPI-DAPAP50, coPI-DAPAP20, coPI-DAPAP10) to the static random access memory (SRAM, volatile, coPI-DAPAP5, coPI-DAPAP1) with the variation of the DAPAP content. Optical and electrochemical characterization show gradually decreasing highest occupied molecular orbital levels and enlarged energy gap with the decrease of the DAPAP moiety, suggesting decreasing charge-transfer effect in the copolyimides, which can account for the observed WORM-SRAM memory conversion. Meanwhile, the charge transfer process was elucidated by quantum chemical calculation at B3LYP/6-31G(d) theory level. This work shows the effect of electron donor content on the memory behavior of polymer electronic materials.

  4. Effect of adjusting pulse durations of functional electrical stimulation cycling on energy expenditure and fatigue after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Ashraf S. Gorgey, MPT, PhD, FACSM

    2015-02-01

    Full Text Available The purpose of the current study was to determine the effects of three different pulse durations (200, 350, and 500 microseconds [P200, P350, and P500, respectively] on oxygen uptake, cycling performance, and energy expenditure (EE percentage of fatigue of the knee extensor muscle group immediately and 48 to 72 h after cycling in persons with spinal cord injury (SCI. A convenience sample of 10 individuals with motor complete SCI participated in a repeated-measures design using a functional electrical stimulation (FES cycle ergometer over a 3 wk period. There was no difference among the three FES protocols on relative oxygen uptake or cycling EE. Delta EE between exercise and rest was 42% greater in both P500 and P350 than in P200 (p = 0.07, whereas recovery oxygen uptake was 23% greater in P350 than in P200 (p = 0.03. There was no difference in the outcomes of the three pulse durations on muscle fatigue. Knee extensor torque significantly decreased immediately after (p < 0.001 and 48 to 72 h after (p < 0.001 FES leg cycling. Lengthening pulse duration did not affect submaximal or relative oxygen uptake or EE, total EE, and time to fatigue. Greater recovery oxygen updake and delta EE were noted in P350 and P500 compared with P200. An acute bout of FES leg cycling resulted in torque reduction that did not fully recover 48 to 72 h after cycling.

  5. Current distribution in skeletal muscle activated by functional electrical stimulation: image-series formulation and isometric recruitment curve.

    Science.gov (United States)

    Livshitz, L M; Einziger, P D; Mizrahi, J

    2000-01-01

    The present work develops an analytical model that allows one to estimate the current distribution within the whole muscle and the resulting isometric recruitment curve (IRC). The quasistatic current distribution, expressed as an image series, i.e., a collection of properly weighted and shifted point-source responses, outlines an extension for more than three layers of the classical image theory in conductive plane-stratified media. Evaluation of the current distribution via the image series expansions requires substantially less computational time than the standard integral representation. The expansions use a unique recursive representation for Green's function, that is a generic characteristic of the stratification. This approach permits one to verify which of the tissue electrical properties are responsible for the current density distribution within the muscle, and how significant their combinations are. In addition, the model permits one to study the effect of different electrode placement on the shape and the magnitude of the potential distribution. A simple IRC model was used for parameter estimation and model verification by comparison with experimentally obtained isometric recruitment curves. Sensitivity of the model to different parameters such as conductivity of the tissues and activation threshold was verified. The resulting model demonstrated characteristic features that were similar to those of experimentally obtained data. The model also quantitatively confirmed the differences existing between surface (transcutaneous) and implanted (percutaneous) electrode stimulation.

  6. Effects of oculo-motor exercise, functional electrical stimulation and proprioceptive neuromuscular stimulation on visual perception of spatial neglect patients.

    Science.gov (United States)

    Park, Si-Eun; Oh, Dae-Sik; Moon, Sang-Hyun

    2016-04-01

    [Purpose] The purpose of this study was to identify the effects of oculo-motor exercise, functional electrical stimulation (FES), and proprioceptive neuromuscular facilitation (PNF) on the visual perception of spatial neglect patients. [Subjects and Methods] The subjects were randomly allocated to 3 groups: an oculo-motor exercise (OME) group, a FES with oculo-motor exercise (FOME) group, and a PNF with oculo-motor exercise (POME) group. The line bisection test (LBT), motor free visual test (MVPT), and Catherine Bergego Scale (CBS) were used to measure visual perception. These were performed 5 times per week for 6 weeks. [Results] The OME group and POME group showed significant improvements according to the LBT and MVPT results, but the FOME group showed no significant improvement. According to the CBS, all 3 groups showed significant improvements. The OME and POME groups showed improvement over the FOME group in the LBT and MVPT. However, there was no significant difference among the three groups according to the CBS. [Conclusion] These results indicate that oculo-motor exercise and PNF with oculo-motor exercise had more positive effects than FES with oculo-motor exercise on the visual perception of spatial neglect patients.

  7. Structural and functional integration between dorsal and ventral language streams as revealed by blunt dissection and direct electrical stimulation.

    Science.gov (United States)

    Sarubbo, Silvio; De Benedictis, Alessandro; Merler, Stefano; Mandonnet, Emmanuel; Barbareschi, Mattia; Dallabona, Monica; Chioffi, Franco; Duffau, Hugues

    2016-11-01

    The most accepted framework of language processing includes a dorsal phonological and a ventral semantic pathway, connecting a wide network of distributed cortical hubs. However, the cortico-subcortical connectivity and the reciprocal anatomical relationships of this dual-stream system are not completely clarified. We performed an original blunt microdissection of 10 hemispheres with the exposition of locoregional short fibers and six long-range fascicles involved in language elaboration. Special attention was addressed to the analysis of termination sites and anatomical relationships between long- and short-range fascicles. We correlated these anatomical findings with a topographical analysis of 93 functional responses located at the terminal sites of the language bundles, collected by direct electrical stimulation in 108 right-handers. The locations of phonological and semantic paraphasias, verbal apraxia, speech arrest, pure anomia, and alexia were statistically analyzed, and the respective barycenters were computed in the MNI space. We found that terminations of main language bundles and functional responses have a wider distribution in respect to the classical definition of language territories. Our analysis showed that dorsal and ventral streams have a similar anatomical layer organization. These pathways are parallel and relatively segregated over their subcortical course while their terminal fibers are strictly overlapped at the cortical level. Finally, the anatomical features of the U-fibers suggested a role of locoregional integration between the phonological, semantic, and executive subnetworks of language, in particular within the inferoventral frontal lobe and the temporoparietal junction, which revealed to be the main criss-cross regions between the dorsal and ventral pathways. Hum Brain Mapp 37:3858-3872, 2016. © 2016 Wiley Periodicals, Inc.

  8. Medical criteria for active physical therapy. Physician guidelines for patient participation in a program of functional electrical rehabilitation.

    Science.gov (United States)

    Phillips, C A

    1987-10-01

    Medical guidelines are presented by which the physician may evaluate a patient for participation in a program of active physical therapy (A.P.T.). A.P.T. system modalities are introduced and defined as: a) isokinetic leg trainer, b) stationary bicycle ergometer, c) outdoor exercise bicycle, and d) Functional Electrical Stimulation (F.E.S.)--Orthosis for ambulation. The physiological responses to these F.E.S. exercise modalities are reviewed. Initial and interim patient evaluations are discussed. The initial patient evaluation includes a history, physical examination, lab tests, and a report summary, all of which culminate in an F.E.S. exercise prescription. The interim patient evaluation is performed for continuation-termination purposes as well as to progress the patient through the various F.E.S. exercise modalities. Specific F.E.S. exercise progression criteria are summarized. The medical criteria are presented with respect to both patient participation in the F.E.S. exercise program and patient monitoring during the exercise itself. Specific medical criteria for patient participation in A.P.T. are organized around eight functional categories: a) level of neurological injury, b) muscular system, c) skeletal system, subdivided into bone criteria and joint criteria, d) cardiovascular system, e) respiratory system, f) urogenital system, g) cutaneous system, and h) psychological system. The medical criteria for patient monitoring during F.E.S. exercise are discussed with respect to: a) cardiovascular monitoring, b) objective patient monitoring, and c) F.E.S. exercise system monitoring. The article concludes with a discussion of informed consent when applied to an emerging treatment modality.

  9. Static electric multipole susceptibilities of the relativistic hydrogen-like atom in the ground state: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Szmytkowski, Radosław

    2016-01-01

    The ground state of the Dirac one-electron atom, placed in a weak, static electric field of definite $2^{L}$-polarity, is studied within the framework of the first-order perturbation theory. The Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30 (1997) 825, erratum: 30 (1997) 2747] is used to derive closed-form analytical expressions for various far-field and near-nucleus static electric multipole susceptibilities of the atom. The far-field multipole susceptibilities --- the polarizabilities $\\alpha_{L}$, electric-to-magnetic cross-susceptibilities $\\alpha_{\\mathrm{E}L\\to\\mathrm{M}(L\\mp1)}$ and electric-to-toroidal-magnetic cross-susceptibilities $\\alpha_{\\mathrm{E}L\\to\\mathrm{T}L}$ --- are found to be expressible in terms of one or two non-terminating generalized hypergeometric functions ${}_{3}F_{2}$ with the unit argument. Counterpart formulas for the near-nucleus multipole susceptibilities --- the electric nuclear shielding constants $\\sigma_{\\mathrm{E}L\\to\\m...

  10. Automated Linear Function Submission-Based Double Auction as Bottom-up Real-Time Pricing in a Regional Prosumers’ Electricity Network

    Directory of Open Access Journals (Sweden)

    Tadahiro Taniguchi

    2015-07-01

    Full Text Available A linear function submission-based double auction (LFS-DA mechanism for a regional electricity network is proposed in this paper. Each agent in the network is equipped with a battery and a generator. Each agent simultaneously becomes a producer and consumer of electricity, i.e., a prosumer, and trades electricity in the regional market at a variable price. In the LFS-DA, each agent uses linear demand and supply functions when they submit bids and asks to an auctioneer in the regional market. The LFS-DA can achieve an exact balance between electricity demand and supply for each time slot throughout the learning phase and was shown capable of solving the primal problem of maximizing the social welfare of the network without any central price setter, e.g., a utility or a large electricity company, in contrast with conventional real-time pricing (RTP. This paper presents a clarification of the relationship between the RTP algorithm derived on the basis of a dual decomposition framework and LFS-DA. Specifically, we proved that the changes in the price profile of the LFS-DA mechanism are equal to those achieved by the RTP mechanism derived from the dual decomposition framework, except for a constant factor.

  11. A functional magnetic resonance imaging study of human brain in pain-related areas induced by electrical stimulation with different intensities

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    2010-01-01

    Full Text Available Background: Pain-related studies have mainly been performed through traditional methods, which lack the rigorous analysis of anatomical locations. Functional magnetic resonance imaging (fMRI is a noninvasive method detecting neural activity, and has the ability to precisely locate related activations in vivo. Moreover, few studies have used painful stimulation of changed intensity to investigate relevant functioning nuclei in the human brain. Aim: This study mainly focused on the pain-related activations induced by electrical stimulation with different intensities using fMRI. Furthermore, the electrophysiological characteristics of different pain-susceptible-neurons were analyzed to construct the pain modulatory network, which was corresponding to painful stimulus of changed intensity. Materials and Methods: Twelve volunteers underwent functional scanning receiving different electrical stimulation. The data were collected and analyzed to generate the corresponding functional activation maps and response time curves related to pain. Results: The common activations were mainly located in several specific regions, including the secondary somatosensory cortex (SII, insula, anterior cingulate cortex (ACC, thalamus, and other cerebral regions. Moreover, innocuous electrical stimulation primarily activated the lateral portions of SII and thalamus, as well as the posterior insula, anterior ACC, whereas noxious electrical stimulation primarily activated the medial portions of SII and thalamus, as well as the anterior insula, the posterior ACC, with larger extensions and greater intensities. Conclusion: Several specified cerebral regions displayed different response patterns during electrical stimulation by means of fMRI, which implied that the corresponding pain-susceptible-neurons might process specific aspects of pain. Elucidation of functions on pain-related regions will help to understand the delicate pain modulation of human brain.

  12. Regularized focusing inversion of time-lapse electrical resistivity data: an approach to parametrize the minimum gradient support functional

    Science.gov (United States)

    Nguyen, Frédéric; Hermans, Thomas

    2015-04-01

    Inversion of time-lapse resistivity data allows obtaining 'snapshots' of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or tracer tests. Based on these snapshots, one can infer qualitative information on the location and morphology of changes occurring in the subsurface but also quantitative estimates on the degree of changes in certain property such as temperature or total dissolved solid content. Analysis of these changes can provide direct insight into flow and transport and associated processes and controlling parameters. However, the reliability of the analysis is dependent on survey geometry, measurement schemes, data error, and regularization. Survey design parameters may be optimized prior to the monitoring survey. Regularization, on the other hand, may be chosen depending on available information collected during the monitoring. Common approaches consider smoothing model changes both in space and time but it is often needed to obtain a sharp temporal anomaly, for example in fractured aquifers. We here propose to use the alternative regularization approach based on minimum gradient support (MGS) (Zhdanov, 2002) for time-lapse surveys which will focus the changes in tomograms snapshots. MGS will limit the occurrences of changes in electrical resistivity but will also restrict the variations of these changes inside the different zones. A commonly encountered difficulty by practitioners in this type of regularization is the choice of an additional parameter, the so-called β, required to define the MGS functional. To the best of our knowledge, there is no commonly accepted or standard methodology to optimize the MGS parameter β. The inversion algorithm used in this study is CRTomo (Kemna 2000). It uses a Gauss-Newton scheme to iteratively minimize an objective function which consists of a data misfit functional and a model constraint functional. A univariate line search is performed

  13. Study on the electric conduction function of carbon black and carbon fiber diphasic electrically conductive concrete%炭黑碳纤维复相导电混凝土的导电性能研究

    Institute of Scientific and Technical Information of China (English)

    卢珍; 吴献; 杨昆

    2014-01-01

    It aimed at the research on the electric conduction function carbon black and carbon fiber diphasic electrically conductive concrete,and analyse the change of resistivity.The methodology adopted as theoretical basis and experimental basis can be used in deicing or snow-melting in future.Carbon black and carbon fiber as the electric conduction is used to improve the electric conduction function of concrete.Conduct the experiment of the electric conduction function of carbon black and carbon fiber diphasic electrically conductive con-crete.The effect of temperature,humidity and plus voltage on resistivity of carbon black and carbon fiber diphasic electricall conductive concrete was analysed.When environment chang,the electric conduction function of concrete will chang too.As the rise of temperature the experimental results showed that the resistivity of carbon black and carbon fiber diphasic electrically conductive concrete will reduct in a certain degree.The resistivity in dry state was higher than the state of wet. As the rise of plus voltage the resistivity of carbon black and car-bon fiber diphasic electrically conductive concrete will reduct in a certain degree.When the voltage is to a certain number ,the resistivity trend to be stabile.%研究了炭黑碳纤维复相导电混凝土的导电性能,分析了导电混凝土的电阻率变化,为实际应用于道路融雪化冰提供理论依据与试验依据。利用纳米导电炭黑和碳纤维作为导电相来改善混凝土的导电性能,进行炭黑碳纤维复相导电混凝土的导电性能试验,分析环境温度、干湿度和外加电压对炭黑碳纤维导电混凝土电阻率的影响。导电混凝土的电阻率受温度、湿度和外加电压的影响,当环境条件发生变化时,导电混凝土的导电性能也会发生变化。炭黑碳纤维复相导电混凝土的电阻率随着温度的升高出现一定程度的减小;干燥状态下的电阻率高于潮湿

  14. Functional electrical stimulation mediated by iterative learning control and 3D robotics reduces motor impairment in chronic stroke

    Directory of Open Access Journals (Sweden)

    Meadmore Katie L

    2012-06-01

    Full Text Available Abstract Background Novel stroke rehabilitation techniques that employ electrical stimulation (ES and robotic technologies are effective in reducing upper limb impairments. ES is most effective when it is applied to support the patients’ voluntary effort; however, current systems fail to fully exploit this connection. This study builds on previous work using advanced ES controllers, and aims to investigate the feasibility of Stimulation Assistance through Iterative Learning (SAIL, a novel upper limb stroke rehabilitation system which utilises robotic support, ES, and voluntary effort. Methods Five hemiparetic, chronic stroke participants with impaired upper limb function attended 18, 1 hour intervention sessions. Participants completed virtual reality tracking tasks whereby they moved their impaired arm to follow a slowly moving sphere along a specified trajectory. To do this, the participants’ arm was supported by a robot. ES, mediated by advanced iterative learning control (ILC algorithms, was applied to the triceps and anterior deltoid muscles. Each movement was repeated 6 times and ILC adjusted the amount of stimulation applied on each trial to improve accuracy and maximise voluntary effort. Participants completed clinical assessments (Fugl-Meyer, Action Research Arm Test at baseline and post-intervention, as well as unassisted tracking tasks at the beginning and end of each intervention session. Data were analysed using t-tests and linear regression. Results From baseline to post-intervention, Fugl-Meyer scores improved, assisted and unassisted tracking performance improved, and the amount of ES required to assist tracking reduced. Conclusions The concept of minimising support from ES using ILC algorithms was demonstrated. The positive results are promising with respect to reducing upper limb impairments following stroke, however, a larger study is required to confirm this.

  15. Band Gap Modulation of Bilayer MoS2 Under Strain Engineering and Electric Field: A Density Functional Theory

    Science.gov (United States)

    Nguyen, Chuong V.; Hieu, Nguyen N.; Ilyasov, Victor V.

    2016-08-01

    In this work, we investigate band-gap tuning in bilayer MoS2 by an external electric field and by applied biaxial strain. Our calculations show that the band gaps of bilayer MoS2 can be tuned by the perpendicular electric field or biaxial strain. The band gaps of bilayer MoS2 decrease with increasing applied electric field or biaxial strain. When the electric field was introduced, electronic levels are split due to the separation of the valence sub-band and the conduction sub-band states. Our calculations also show that the change in the band gap of bilayer MoS2 is due to the separation of electronic levels by electric field via the Stark effect. At the electric field E_{Field} = 5.5 V/nm or biaxial strain ɛ = 15%, bilayer MoS2 becomes metallic. The semiconductor-metal phase transition in bilayer MoS2 plays an important role in its application for nanodevices.

  16. Three-dimensional analytical solution for a transversely isotropic functionally graded piezoelectric circular plate subject to a uniform electric potential difference

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper studies the problem of a functionally graded piezoelectric circular plate subjected to a uniform electric potential difference between the upper and lower surfaces. By assuming the generalized displacements in appropriate forms,five differential equations governing the generalized displacement functions are derived from the equilibrium equations. These displacement functions are then obtained in an explicit form,which still involve four undetermined integral constants,through a step-by-step integration which properly incorporates the boundary conditions at the upper and lower surfaces. The boundary conditions at the cylindrical surface are then used to determine the integral constants. Hence,three-dimen sional analytical solutions for electrically loaded functionally graded piezoelectric circular plates with free or simply-supported edge are completely determined. These solutions can account for an arbitrary material variation along the thickness,and thus can be readily degenerated into those for a homogenous plate. A numerical example is finally given to show the validity of the analysis,and the effect of material inhomogeneity on the elastic and electric fields is discussed.

  17. Functional electrical stimulation increases neural stem/progenitor cell proliferation and neurogenesis in the subventricular zone of rats with stroke

    Institute of Scientific and Technical Information of China (English)

    LIU Hui-hua; XIANG Yun; YAN Tie-bin; TAN Zhi-mei; LI Sheng-huo; HE Xiao-kuo

    2013-01-01

    Background Functional electrical stimulation (FES) is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis.In this study,we investigated whether postischemic FES could improve functional outcomes and modulate neurogenesis in the subventricular zone (SVZ) after focal cerebral ischemia.Methods Adult male Sprague-Dawley rats with permanent middle cerebral artery occlusion (MCAO) were randomly assigned to the control group,the placebo stimulation group,and the FES group.The rats in each group were further assigned to one of four therapeutic periods (1,3,7,or 14 days).FES was delivered 48 hours after the MCAO procedure and divided into two 10-minute sessions on each day of treatment with a 10-minute rest between them.Two intraperitoneal injections of bromodeoxyuridine (BrdU) were given 4 hours apart every day beginning 48 hours after the MCAO.Neurogenesis was evaluated by immunofluorescence staining.Wnt-3 which is strongly implicated in the proliferation and differentiation of neural stem cells (NSCs) was investigated by Western blotting analysis.The data wera subjected to oneway analysis of variance (ANOVA),followed by a Tukey/Kramer or Dunnett post hoc test.Results FES significantly increased the number of BrdU-positive cells and BrdU/glial flbrillary acidic protein doublepositive neural progenitor cells in the SVZ on days 7 and 14 of the treatment (P <0.05).The number of BrdU/doublecortin (DCX) double-positive migrating neuroblast cells in the ipsilateral SVZ on day 14 of the FES treatment group ((522.77±33.32) cells/mm2) was significantly increased compared with the control group ((262.58±35.11) cells/mm2,P <0.05) and the placebo group ((266.17±47.98) cells/mm2,P <0.05).However,only a few BrdU/neuron-specific nuclear protein-positive cells were observed by day 14 of the treatment.At day 7,Wnt-3 was upregulated in the ipsilateral SVZs of the rats receiving

  18. Appearance of perfect amorphous linear bulk polyethylene under applied electric field and the analysis by radial distribution function and direct tunneling effect.

    Science.gov (United States)

    Zhang, Rong; Bin, Yuezhen; Yang, Wenxiao; Fan, Shaoyan; Matsuo, Masaru

    2014-02-27

    Without melting flow, linear ultrahigh molecular weight polyethylene (UHMWPE) provided X-ray intensity curve from only amorphous halo at 129.0 °C (surface temperature, Ts arisen by Joule heat) lower than the conventionally known melting point 145.5 °C on applying electric field to UHMWPE-nickel-coated carbon fiber (NiCF) composite. Such surprising phenomenon was analyzed by simultaneous measurements of X-ray intensity, electric current, and Ts as a function of time. The calculated radial distribution function revealed the amorphous structure with disordered chain arrangement. The appearance of such amorphous phase was arisen by the phenomenon that the transferring electrons between overlapped adjacent NiCFs by tunneling effect struck together with X-ray photons and some of the transferring electron flown out from the gap to UHMWPE matrix collided against carbon atoms of UHMWPE. The impact by the collision caused disordering chain arrangement in crystal grains.

  19. Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    Science.gov (United States)

    Stefańska, Patrycja

    2016-02-01

    We consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength B of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30, 825 (1997), 10.1088/0953-4075/30/4/007; J. Phys. B 30, 2747 (1997), 10.1088/0953-4075/30/11/023], We derive a closed-form expression for the electric quadrupole moment induced in the atom in an arbitrary discrete energy eigenstate. The result, which has the form of a double finite sum involving the generalized hypergeometric functions 3F2 of the unit argument, agrees with the earlier relativistic formula for that quantity, obtained by us for the ground state of the atom.

  20. Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Stefańska, Patrycja

    2016-01-01

    We consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength B of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30, 825 (1997); 30, 2747(E) (1997)], we derive a closed-form expression for the electric quadrupole moment induced in the atom in an arbitrary discrete energy eigenstate. The result, which has the form of a double finite sum involving the generalized hypergeometric functions 3F2 of the unit argument, agrees with the earlier relativistic formula for that quantity, obtained by us for the ground state of the atom.

  1. Electric Machine Analysis, Control and Verification for Mechatronics Motion Control Applications, Using New MATLAB Built-in Function and Simulink Model

    Directory of Open Access Journals (Sweden)

    Farhan A. Salem

    2014-05-01

    Full Text Available This paper proposes a new, simple and user–friendly MATLAB built-in function, mathematical and Simulink models, to be used to early identify system level problems, to ensure that all design requirements are met, and, generally, to simplify Mechatronics motion control design process including; performance analysis and verification of a given electric DC machine, proper controller selection and verification for desired output speed or angle.

  2. Facile synthesis of polypyrrole functionalized nickel foam with catalytic activity comparable to Pt for the poly-generation of hydrogen and electricity

    Science.gov (United States)

    Tang, Tiantian; Li, Kan; Shen, Zhemin; Sun, Tonghua; Wang, Yalin; Jia, Jinping

    2016-01-01

    Polypyrrole functionalized nickel foam is facilely prepared through the potentiostatic electrodeposition. The PPy-functionalized Ni foam functions as a hydrogen-evolution cathode in a rotating disk photocatalytic fuel cell, in which hydrogen energy and electric power are generated by consuming organic wastes. The PPy-functionalized Ni foam cathode exhibits stable catalytic activities after thirteen continuous runs. Compared with net or plate structure, the Ni foam with a unique three-dimensional reticulate structure is conducive to the electrodeposition of PPy. Compared with Pt-group electrode, PPy-coated Ni foam shows a satisfactory catalytic performance for the H2 evolution. The combination of PPy and Ni forms a synergistic effect for the rapid trapping and removal of proton from solution and the catalytic reduction of proton to hydrogen. The PPy-functionalized Ni foam could be applied in photocatalytic and photoelectrochemical generation of H2. In all, we report a low cost, high efficient and earth abundant PPy-functionalized Ni foam with a satisfactory catalytic activities comparable to Pt for the practical application of poly-generation of hydrogen and electricity.

  3. Effects of Robot-assisted Gait Training Combined with Functional Electrical Stimulation on Recovery of Locomotor Mobility in Chronic Stroke Patients: A Randomized Controlled Trial.

    Science.gov (United States)

    Bae, Young-Hyeon; Ko, Young Jun; Chang, Won Hyuk; Lee, Ju Hyeok; Lee, Kyeong Bong; Park, Yoo Jung; Ha, Hyun Geun; Kim, Yun-Hee

    2014-12-01

    [Purpose] The purpose of the present study was to investigate the effects of robot-assisted gait training combined with functional electrical stimulation on locomotor recovery in patients with chronic stroke. [Subjects] The 20 subjects were randomly assigned into either an experimental group (n = 10) that received a combination of robot-assisted gait training and functional electrical stimulation on the ankle dorsiflexor of the affected side or a control group (n = 10) that received robot-assisted gait training only. [Methods] Both groups received the respective therapies for 30 min/day, 3 days/week for 5 weeks. The outcome was measured using the Modified Motor Assessment Scale (MMAS), Timed Up-and-Go Test (TUG), Berg Balance Scale (BBS), and gait parameters through gait analysis (Vicon 370 motion analysis system, Oxford Metrics Ltd., Oxford, UK). All the variables were measured before and after training. [Results] Step length and maximal knee extension were significantly greater than those before training in the experimental group only. Maximal Knee flexion showed a significant difference between the experimental and control groups. The MMAS, BBS, and TUG scores improved significantly after training compared with before training in both groups. [Conclusion] We suggest that the combination of robot-assisted gait training and functional electrical stimulation encourages patients to actively participate in training because it facilitates locomotor recovery without the risk of adverse effects.

  4. Curie temperature of Co-doped TiO2 as functions of carrier density and Co content evaluated from electrical transport and magnetization at low temperature regime

    Directory of Open Access Journals (Sweden)

    Thantip S. Krasienapibal

    2016-05-01

    Full Text Available Curie temperature (TC of anatase Co-doped TiO2 epitaxial thin films was systematically investigated as functions of carrier density (n and Co content (x by electrical transport and magnetization measurements at low temperature regime. The estimated TC from both measurements showed similar TC. For x = 0.03, 0.05, and 0.07, non-monotonic TC vs. n relations were observed, whereas TC was monotonically increasing function of n for x = 0.10. Possible mechanism of high TC ferromagnetism for this compound was discussed.

  5. Comparison of the Effect of Exercise Therapy with Transcutaneous Electrical Nerve Stimulation on Improvement of Pain and Function in Patients with Patellofemoral Pain Syndrome

    Directory of Open Access Journals (Sweden)

    A Akbari

    2008-04-01

    Full Text Available ABSTRACT: Introduction & Objective: One of the most common disorders of the knee joint in adult is patellofemoral pain syndrome. Sometimes it becomes chronic and causes activity limitation. This study aimed to compare the efficacy of exercise therapy with Transcutaneous Electrical Nerve Stimulation on improvement of pain intensity, knee function, muscle atrophy and range of knee flexion. Materials & Methods: This double-blind, randomized clinical trial was carried out in Zahedan Razmejo-Moghadam Physiotherapy Clinic, in 2007. Thirty-two patients with patellofemoral pain syndrome were recruited through simple non-probability sampling. Subjects were randomly assigned to one of the equal groups, exercise therapy (including hip, knee, and leg muscles strengthening and stretching exercises or electrical stimulation group. Before and after intervention, we assessed pain through Visual Analog Scale (VAS (ordinal, function (ordinal with Knee Injury and Osteoarthritis Outcome Score (KOOS, thigh circumference with tape measure (centimeter and range of knee flexion with goniometer (degree. A 10 session treatment program, three sessions per week and one hour per session was performed for both groups. Independent t-test or Mann-Whitney U and paired t-test or Wilcoxon were used for comparison between the pretreatment and post treatment results between groups and within groups, in SPSS software, respectively. Results: The mean total score of knee function increased from 100.53±19.25 to 130.87±18.25 in the electrical stimulation group and from 107.67±22.69 to 131.47±15.11 in the exercise therapy group (p=0.001. The mean score of knee function subscales including symptoms, pain, functional limitation, recreational activity, and life style improved in both groups (p<0.05. The pain score and range of knee flexion improved in both groups (p<0.05. After treatment, range of knee flexion significantly increased in the exercise group compared with the electrical

  6. Potential of M-Wave Elicited by Double Pulse for Muscle Fatigue Evaluation in Intermittent Muscle Activation by Functional Electrical Stimulation for Motor Rehabilitation

    Directory of Open Access Journals (Sweden)

    Naoto Miura

    2016-01-01

    Full Text Available Clinical studies on application of functional electrical stimulation (FES to motor rehabilitation have been increasing. However, muscle fatigue appears early in the course of repetitive movement production training by FES. Although M-wave variables were suggested to be reliable indices of muscle fatigue in long lasting constant electrical stimulation under the isometric condition, the ability of M-wave needs more studies under intermittent stimulation condition, because the intervals between electrical stimulations help recovery of muscle activation level. In this paper, M-waves elicited by double pulses were examined in muscle fatigue evaluation during repetitive movements considering rehabilitation training with surface electrical stimulation. M-waves were measured under the two conditions of repetitive stimulation: knee extension force production under the isometric condition and the dynamic movement condition by knee joint angle control. Amplitude of M-wave elicited by the 2nd pulse of a double pulse decreased during muscle fatigue in both measurement conditions, while the change in M-waves elicited by single pulses in a stimulation burst was not relevant to muscle fatigue in repeated activation with stimulation interval of 1 s. Fatigue index obtained from M-waves elicited by 2nd pulses was suggested to provide good estimation of muscle fatigue during repetitive movements with FES.

  7. From the intrinsic properties to the functional role of a neuron phenotype: an example from electric fish during signal trade-off.

    Science.gov (United States)

    Nogueira, Javier; Caputi, Angel A

    2013-07-01

    This review deals with the question: what is the relationship between the properties of a neuron and the role that the neuron plays within a given neural circuit? Answering this kind of question requires collecting evidence from multiple neuron phenotypes and comparing the role of each type in circuits that perform well-defined computational tasks. The focus here is on the spherical neurons in the electrosensory lobe of the electric fish Gymnotus omarorum. They belong to the one-spike-onset phenotype expressed at the early stages of signal processing in various sensory modalities and diverse taxa. First, we refer to the one-spike neuron intrinsic properties, their foundation on a low-threshold K(+) conductance, and the potential roles of this phenotype in different circuits within a comparative framework. Second, we present a brief description of the active electric sense of weakly electric fish and the particularities of spherical one-spike-onset neurons in the electrosensory lobe of G. omarorum. Third, we introduce one of the specific tasks in which these neurons are involved: the trade-off between self- and allo-generated signals. Fourth, we discuss recent evidence indicating a still-undescribed role for the one-spike phenotype. This role deals with the blockage of the pathway after being activated by the self-generated electric organ discharge and how this blockage favors self-generated electrosensory information in the context of allo-generated interference. Based on comparative analysis we conclude that one-spike-onset neurons may play several functional roles in animal sensory behavior. There are specific adaptations of the neuron's 'response function' to the circuit and task. Conversely, the way in which a task is accomplished depends on the intrinsic properties of the neurons involved. In short, the role of a neuron within a circuit depends on the neuron and its functional context.

  8. Modelling motor cortex stimulation for chronic pain control. electrical potential field, activating functions and responses of simple nerve fibre models

    NARCIS (Netherlands)

    Manola, L.; Roelofsen, B.H.; Holsheimer, J.; Marani, E.; Geelen, J.A.G.

    2005-01-01

    This computer modelling study on motor cortex stimulation (MCS) introduced a motor cortex model, developed to calculate the imposed electrical potential field characteristics and the initial response of simple fibre models to stimulation of the precentral gyrus by an epidural electrode, as applied i

  9. Design of a 32-Channel EEG System for Brain Control Interface Applications

    Directory of Open Access Journals (Sweden)

    Ching-Sung Wang

    2012-01-01

    Full Text Available This study integrates the hardware circuit design and the development support of the software interface to achieve a 32-channel EEG system for BCI applications. Since the EEG signals of human bodies are generally very weak, in addition to preventing noise interference, it also requires avoiding the waveform distortion as well as waveform offset and so on; therefore, the design of a preamplifier with high common-mode rejection ratio and high signal-to-noise ratio is very important. Moreover, the friction between the electrode pads and the skin as well as the design of dual power supply will generate DC bias which affects the measurement signals. For this reason, this study specially designs an improved single-power AC-coupled circuit, which effectively reduces the DC bias and improves the error caused by the effects of part errors. At the same time, the digital way is applied to design the adjustable amplification and filter function, which can design for different EEG frequency bands. For the analog circuit, a frequency band will be taken out through the filtering circuit and then the digital filtering design will be used to adjust the extracted frequency band for the target frequency band, combining with MATLAB to design man-machine interface for displaying brain wave. Finally the measured signals are compared to the traditional 32-channel EEG signals. In addition to meeting the IFCN standards, the system design also conducted measurement verification in the standard EEG isolation room in order to demonstrate the accuracy and reliability of this system design.

  10. 直接脑控机器人接口技术%Direct Brain-controlled Robot Interface Technology

    Institute of Scientific and Technical Information of China (English)

    伏云发; 王越超; 李洪谊; 徐保磊; 李永程

    2012-01-01

    直接脑控机器人接口(Brain-controlled robot interface,BCRI)是一种新型的人-机器人接口技术,是脑-机器接口/脑-计算机接口 (Brain-machine interface,BMI/Brain-computer interface,BCI)在机器人控制领域的重要应用和研究方向.研究者相继在Nature、Science和其他重要国际期刊上报道了相关的实验研究和开发,目前已成为国际前沿研究热点.本文主要围绕BCRI中的控制策略、BMI/BCI模块与机器人多层控制模块的适应和融合、BCRI中的脑信号自适应分类算法以及人、BMI/BCI模块和机器人控制系统的三边自适应展开论述,分析了目前的研究情况、存在的局限和面临的若干重要问题,指出进一步的研究思路和方向.%Direct brain-controlled robot interface (BCRI) is a new type human-robot interface which is an important research and development direction for brain-machine interface (BMI) / brain-computer interface (BCI) in the robot control field. Many experimental researches and developments for BCRI were reported by Nature, Science and other important international journals and it has become an international frontier research hotspot. The paper mainly discussed the control strategies for BCRI, the adaptation and fusion between BMI/BCI module and robot multilayer control architecture module, the adaptive classification algorithms for brain signal used in BCRI and the trilateral adaptation among human, BMI/BCI module and robot control system. The current situation and limitation for BCRI and some important problems faced by BCRI were analyzed and the further research ideas and directions were also pointed out.

  11. Achieving high performance electric field induced strain: a rational design of hyperbranched aromatic polyamide functionalized graphene-polyurethane dielectric elastomer composites.

    Science.gov (United States)

    Chen, Tian; Qiu, Jinhao; Zhu, Kongjun; Li, Jinhuan; Wang, Jingwen; Li, Shuqin; Wang, Xiaoliang

    2015-03-26

    Dielectric elastomers have great potentials as flexible actuators in micro-electromechanical systems (MEMS) due to their large deformation, light weight, mechanical compliancy, and low cost. The low dielectric constant of these elastomers requires a rather high voltage electric field, which has greatly limited their applications. In this work, a diaphragm-type flexible microactuator comprising a hyperbranched aromatic polyamide functionalized graphene (HAPFG) filler embedded into the polyurethane (PU) dielectric elastomer matrix is described. The rational designed HAPFG sheets exhibits uniform dispersion in PU matrix and strong adhesion with the matrix by hydrogen-bond coupling. Consequently, the HAPFG-PU composites possess high dielectric performance and low loss modulus. The effect of hyperbranched aromatic polyamide functionalized graphene on high voltage electric field induced strain was experimentally investigated using the Fotonic sensor. The high electric field response of the composite was discussed by applying different kinds of alternating-current field. In addition, a comparison of the breakdown strength between the HAPFG-PU composite and the pure PU was carried out.

  12. A NEW MODEL AND IMPROVED CABLE FUNCTION FOR REPRESENTING THE ACTIVATING PERIPHERAL NERVES BY A TRANSVERSE ELECTRIC FIELD DURING MAGNETIC STIMULATION

    Institute of Scientific and Technical Information of China (English)

    Yu Hui; Zheng Chongxun; Wang Haiyan; Wang Yi

    2005-01-01

    Objective Previous studies of peripheral nerves activation during magnetic stimulation have focused almost exclusively on the cause of high external parallel electric field along the nerves, whereas the effect of the transverse component has been ignored. In the present paper, the classical cable function is modified to represent the excitation of peripheral nerves stimulated by a transverse electric field during magnetic stimulation. Methods Responses of the Ranvier nodes to a transverse-field are thoroughly investigated by mathematic simulation. Results The simulation demonstrates that the excitation results from the net inward current driven by an external field. Based on a two-stage process, a novel model is introduced to describe peripheral nerves stimulated by a transverse-field. Based on the new model, the classical cable function is modified. Conclusion Using this modified cable equation, the excitation threshold of peripheral nerves in a transverse field during MS is obtained. The modified cable equation can be used to represent the response of peripheral nerves by an arbitrary electric field.

  13. 3D Modelling and monitoring of denervated muscle under Functional Electrical Stimulation treatment and associated bone structural changes

    Directory of Open Access Journals (Sweden)

    Paolo Gargiulo

    2011-03-01

    Full Text Available A novel clinical rehabilitation method for patients who have permanent and non recoverable muscle denervation in the legs was developed in the frame of the European Project RISE. The technique is based on FES and the project results shows, in these severely disabled patients, restoration of muscle tissue and function. This study propose novel methods based on image processing technique and medical modelling to monitor growth in denervated muscle treated with FES. Geometrical and structural changes in muscle and bone are studied and modelled. Secondary effects on the bone mineral density produced by the stimulation treatment and due the elicited muscle contraction are also investigated. The restoration process in DDM is an important object of discussion since there isn’t yet a complete understanding of the mechanisms regulating growth in denervated muscle. This study approaches the problem from a macroscopic point of view, developing 3-dimensional models of the whole stimulated muscles and following changes in volume, geometry and density very accurately. The method is based on the acquisition of high resolution Spiral CT scans from patients who have long-term flaccid paraplegia and the use of special image processing tools allowing tissue discriminations and muscle segmentation. Three patients were measured at different points of time during 4 years of electrical stimulation treatment. In this study is quantitatively demonstrated the influences of FES treatment on the different quadriceps bellies. The rectus femoris muscle is positioned in the middle of the quadriceps and responds (in general better to stimulation. In a patient with abundant adipose tissue surrounding the quadriceps, rectus femoris almost doubled the volume during the FES treatment while in the other bellies the changes measured were minimal. The analysis of the density shows clearly a restoration of the muscular structure in the growing muscle. The remarkable increase of

  14. Funktionelle elektrische Stimulation bei Schwäche der Vorfußhebung // Functional electrical Stimulation and drop foot

    Directory of Open Access Journals (Sweden)

    Pinter MM

    2016-01-01

    Full Text Available Drop foot is a common problem following neurological conditions such as stroke, multiple sclerosis, brain injury and incomplete spinal cord injury, consisting in the inability to lift the foot in the swing phase of the gait cycle. Since dropped foot is frequently associated with spasticity and more complex movement problems affecting the whole person, it can result in tripping and falling.br Functional electrical Stimulation (FES devices are designed to address this problem. The peroneal nerve is stimulated using surface electrodes at its most superficial position in its course, where it passes over the head of the fibula bone. The peroneal nerve stimulation induces activity in the tibialis anterior and peroneous longus muscles, causing dorsiflexion and eversion of the foot. The stimulation is synchronised to the gait using a pressure sensitive heel switch. When weight is taken from the switch, stimulation is given. FES results in an economisation of gait and an improvement of walking speed and walking distance.br Recently, an implantable 4-channel drop foot stimulator with independent electrode adjustment resulting in a more specific stimulation showed an improvement of walking speed and a restoration of gait in patients with stroke. The therapeutic effect might be improved compared with surface stimulation. p bKurzfassung:/b Die Schwäche der Vorfußhebung ist ein weit verbreitetes Problem bei neurologischen Erkrankungen wie Schlaganfall, Multiple Sklerose, Schädelhirntrauma und inkomplettem Querschnittsyndrom und führt zu einer insuffizienten Hebung des Vorfußes in der Schwungphase des Gangzyklus. Vielfach ist die Schwäche der Vorfußhebung assoziert mit Spastizität und komplexeren motorischen Problemen, dies führt zu gehäuftem Stolpern und Stürzen.br Die funktionelle elektrische Stimulation (FES ist eine Therapiemodalität zur Korrektur dieses motorischen Problems. Der N. peronaeus wird mittels Oberflächenelektroden, platziert am

  15. Structural and Functional Effect of an Oscillating Electric Field on the Dopamine-D3 Receptor: A Molecular Dynamics Simulation Study

    Science.gov (United States)

    Fallah, Zohreh; Jamali, Yousef; Rafii-Tabar, Hashem

    2016-01-01

    Dopamine as a neurotransmitter plays a critical role in the functioning of the central nervous system. The structure of D3 receptor as a member of class A G-protein coupled receptors (GPCRs) has been reported. We used MD simulation to investigate the effect of an oscillating electric field, with frequencies in the range 0.6–800 GHz applied along the z-direction, on the dopamine-D3R complex. The simulations showed that at some frequencies, the application of an external oscillating electric field along the z-direction has a considerable effect on the dopamine-D3R. However, there is no enough evidence for prediction of changes in specific frequency, implying that there is no order in changes. Computing the correlation coefficient parameter showed that increasing the field frequency can weaken the interaction between dopamine and D3R and may decrease the Arg128{3.50}-Glu324{6.30} distance. Because of high stability of α helices along the z-direction, applying an oscillating electric field in this direction with an amplitude 10-time higher did not have a considerable effect. However, applying the oscillating field at the frequency of 0.6 GHz along other directions, such as X-Y and Y-Z planes, could change the energy between the dopamine and the D3R, and the number of internal hydrogen bonds of the protein. This can be due to the effect of the direction of the electric field vis-à-vis the ligands orientation and the interaction of the oscillating electric field with the dipole moment of the protein. PMID:27832207

  16. Intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation for preservation of facial nerve function in patients with large acoustic neuroma

    Institute of Scientific and Technical Information of China (English)

    LIU Bai-yun; TIAN Yong-ji; LIU Wen; LIU Shu-ling; QIAO Hui; ZHANG Jun-ting; JIA Gui-jun

    2007-01-01

    Background Although various monitoring techniques have been used routinely in the treatment of the lesions in the skull base, iatrogenic facial paresis or paralysis remains a significant clinical problem. The aim of this study was to investigate the effect of intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation on preservation of facial nerve function.Method From January to November 2005, 19 patients with large acoustic neuroma were treated using intraoperative facial motor evoked potentials monitoring with transcranial electrical stimulation (TCEMEP) for preservation of facial nerve function. The relationship between the decrease of MEP amplitude after tumor removal and the postoperative function of the facial nerve was analyzed.Results MEP amplitude decreased more than 75% in 11 patients, of which 6 presented significant facial paralysis (H-B grade 3), and 5 had mild facial paralysis (H-B grade 2). In the other 8 patients, whose MEP amplitude decreased less than 75%, 1 experienced significant facial paralysis, 5 had mild facial paralysis, and 2 were normal.Conclusions Intraoperative TCEMEP can be used to predict postoperative function of the facial nerve. The decreased MEP amplitude above 75 % is an alarm point for possible severe facial paralysis.

  17. A comparison of density functional theory and coupled cluster methods for the calculation of electric dipole polarizability gradients of methane

    DEFF Research Database (Denmark)

    Paidarová, Ivana; Sauer, Stephan P. A.

    2012-01-01

    We have compared the performance of density functional theory (DFT) using five different exchange-correlation functionals with four coupled cluster theory based wave function methods in the calculation of geometrical derivatives of the polarizability tensor of methane. The polarizability gradient...

  18. Hybrid neuroprosthesis for the upper limb: combining brain-controlled neuromuscular stimulation with a multi-joint arm exoskeleton

    Directory of Open Access Journals (Sweden)

    Florian Grimm

    2016-08-01

    Full Text Available Brain-machine interface-controlled (BMI neurofeedback training aims to modulate cortical physiology and is applied during neurorehabilitation to increase the responsiveness of the brain to subsequent physiotherapy. In a parallel line of research, robotic exoskeletons are used in goal-oriented rehabilitation exercises for patients with severe motor impairment to extend their range of motion and the intensity of training. Furthermore, neuromuscular electrical stimulation (NMES is applied in neurologically impaired patients to restore muscle strength by closing the sensorimotor loop. In this proof-of-principle study, we explored an integrated approach for providing assistance as needed to amplify the task-related range of motion and the movement-related brain modulation during rehabilitation exercises of severely impaired patients. For this purpose, we combined these three approaches (BMI, NMES, and exoskeleton in an integrated neuroprosthesis and studied the feasibility of this device in seven severely affected chronic stroke patients who performed wrist flexion and extension exercises while receiving feedback via a virtual environment. They were assisted by a gravity-compensating, seven degree-of-freedom exoskeleton which was attached to the paretic arm. Neuromuscular electrical stimulation was applied to the wrist extensor and flexor muscles during the exercises and was controlled by a hybrid BMI based on both sensorimotor cortical desynchronization (ERD and electromyography (EMG activity. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e. induced no overt support. The hybrid BMI controlled the stimulation significantly better than the offline analyzed ERD (p=0.028 or EMG (p=0.021 modality alone. Neuromuscular stimulation could be well integrated into the exoskeleton-based training and amplified both the task-related range of motion (p=0.009 and the movement-related brain modulation (p=0

  19. Inspiratory Muscle Training and Functional Electrical Stimulation for Treatment of Heart Failure With Preserved Ejection Fraction: Rationale and Study Design of a Prospective Randomized Controlled Trial.

    Science.gov (United States)

    Palau, Patricia; Domínguez, Eloy; López, Laura; Heredia, Raquel; González, Jessika; Ramón, Jose María; Serra, Pilar; Santas, Enrique; Bodi, Vicente; Sanchis, Juan; Chorro, Francisco J; Núñez, Julio

    2016-08-01

    Heart failure with preserved ejection fraction (HFpEF) has become the most prevalent form of heart failure in developed countries. Regrettably, there is no evidence-based effective therapy for HFpEF. We seek to evaluate whether inspiratory muscle training, functional electrical stimulation, or a combination of both can improve exercise capacity as well as left ventricular diastolic function, biomarker profile, quality of life (QoL), and prognosis in patients with HFpEF. A total of 60 stable symptomatic patients with HFpEF (New York Heart Association class II-III/IV) will be randomized (1:1:1:1) to receive a 12-week program of inspiratory muscle training, functional electrical stimulation, a combination of both, or standard care alone. The primary endpoint of the study is change in peak exercise oxygen uptake; secondary endpoints are changes in QoL, echocardiogram parameters, and prognostic biomarkers. As of March 21, 2016, thirty patients have been enrolled. Searching for novel therapies that improve QoL and autonomy in the elderly with HFpEF has become a health care priority. We believe that this study will add important knowledge about the potential utility of 2 simple and feasible physical interventions for the treatment of advanced HFpEF.

  20. Mirror therapy combined with biofeedback functional electrical stimulation for motor recovery of upper extremities after stroke: a pilot randomized controlled trial.

    Science.gov (United States)

    Kim, Jung Hee; Lee, Byoung-Hee

    2015-06-01

    The objective of this study was to evaluate the effects of mirror therapy in combination with biofeedback functional electrical stimulation (BF-FES) on motor recovery of the upper extremities after stroke. Twenty-nine patients who suffered a stroke > 6 months prior participated in this study and were randomly allocated to three groups. The BF-FES + mirror therapy and FES + mirror therapy groups practiced training for 5 × 30 min sessions over a 4-week period. The control group received a conventional physical therapy program. The following clinical tools were used to assess motor recovery of the upper extremities: electrical muscle tester, electrogoniometer, dual-inclinometer, electrodynamometer, the Box and Block Test (BBT) and Jabsen Taylor Hand Function Test (JHFT), the Functional Independence Measure, the Modified Ashworth Scale, and the Stroke Specific Quality of Life (SSQOL) assessment. The BF-FES + mirror therapy group showed significant improvement in wrist extension as revealed by the Manual Muscle Test and Range of Motion (p therapy group showed significant improvement in the BBT, JTHT, and SSQOL compared with the FES + mirror therapy group and control group (p therapy induced motor recovery and improved quality of life. These results suggest that mirror therapy, in combination with BF-FES, is feasible and effective for motor recovery of the upper extremities after stroke.

  1. State of charge estimation of Li-ion batteries in an electric vehicle based on a radial-basis-function neural network

    Institute of Scientific and Technical Information of China (English)

    Bi Jun; Shao Sai; Guan Wei; Wang Lu

    2012-01-01

    The on-line estimation of the state of charge (SOC) of the batteries is important for the reliable running of the pure electric vehicle in practice.Because a nonlinear feature exists in the batteries and the radial-basis-function neural network (RBF NN) has good characteristics to solve the nonlinear problem,a practical method for the SOC estimation of batteries based on the RBF NN with a small number of input variables and a simplified structure is proposed.Firstly,in this paper,the model of on-line SOC estimation with the RBF NN is set.Secondly,four important factors for estimating the SOC are confirmed based on the contribution analysis method,which simplifies the input variables of the RBF NN and enhances the real-time performance of estimation.Finally,the pure electric buses with LiFePO4Li-ion batteries running during the period of the 2010 Shanghai World Expo are considered as the experimental object.The performance of the SOC estimation is validated and evaluated by the battery data from the electric vehicle.

  2. Electricity generation and bivalent copper reduction as a function of operation time and cathode electrode material in microbial fuel cells

    Science.gov (United States)

    Wu, Dan; Huang, Liping; Quan, Xie; Li Puma, Gianluca

    2016-03-01

    The performance of carbon rod (CR), titanium sheet (TS), stainless steel woven mesh (SSM) and copper sheet (CS) cathode materials are investigated in microbial fuel cells (MFCs) for simultaneous electricity generation and Cu(II) reduction, in multiple batch cycle operations. After 12 cycles, the MFC with CR exhibits 55% reduction in the maximum power density and 76% increase in Cu(II) removal. In contrast, the TS and SSM cathodes at cycle 12 show maximum power densities of 1.7 (TS) and 3.4 (SSM) times, and Cu(II) removal of 1.2 (TS) and 1.3 (SSM) times higher than those observed during the first cycle. Diffusional resistance in the TS and SSM cathodes is found to appreciably decrease over time due to the copper deposition. In contrast to CR, TS and SSM, the cathode made with CS is heavily corroded in the first cycle, exhibiting significant reduction in both the maximum power density and Cu(II) removal at cycle 2, after which the performance stabilizes. These results demonstrate that the initial deposition of copper on the cathodes of MFCs is crucial for efficient and continuous Cu(II) reduction and electricity generation over prolonged time. This effect is closely associated with the nature of the cathode material. Among the materials examined, the SSM is the most effective and inexpensive cathode for practical use in MFCs.

  3. Electrical percolation threshold of cementitious composites possessing self-sensing functionality incorporating different carbon-based materials

    Science.gov (United States)

    Al-Dahawi, Ali; Haroon Sarwary, Mohammad; Öztürk, Oğuzhan; Yıldırım, Gürkan; Akın, Arife; Şahmaran, Mustafa; Lachemi, Mohamed

    2016-10-01

    An experimental study was carried out to understand the electrical percolation thresholds of different carbon-based nano- and micro-scale materials in cementitious composites. Multi-walled carbon nanotubes (CNTs), graphene nanoplatelets (GNPs) and carbon black (CB) were selected as the nano-scale materials, while 6 and 12 mm long carbon fibers (CF6 and CF12) were used as the micro-scale carbon-based materials. After determining the percolation thresholds of different electrical conductive materials, mechanical properties and piezoresistive properties of specimens produced with the abovementioned conductive materials at percolation threshold were investigated under uniaxial compressive loading. Results demonstrate that regardless of initial curing age, the percolation thresholds of CNT, GNP, CB and CFs in ECC mortar specimens were around 0.55%, 2.00%, 2.00% and 1.00%, respectively. Including different carbon-based conductive materials did not harm compressive strength results; on the contrary, it improved overall values. All cementitious composites produced with carbon-based materials, with the exception of the control mixtures, exhibited piezoresistive behavior under compression, which is crucial for sensing capability. It is believed that incorporating the sensing attribute into cementitious composites will enhance benefits for sustainable civil infrastructures.

  4. Restoring the consistency with the contact density theorem of a classical density functional theory of ions at a planar electrical double layer.

    Science.gov (United States)

    Gillespie, Dirk

    2014-11-01

    Classical density functional theory (DFT) of fluids is a fast and efficient theory to compute the structure of the electrical double layer in the primitive model of ions where ions are modeled as charged, hard spheres in a background dielectric. While the hard-core repulsive component of this ion-ion interaction can be accurately computed using well-established DFTs, the electrostatic component is less accurate. Moreover, many electrostatic functionals fail to satisfy a basic theorem, the contact density theorem, that relates the bulk pressure, surface charge, and ion densities at their distances of closest approach for ions in equilibrium at a smooth, hard, planar wall. One popular electrostatic functional that fails to satisfy the contact density theorem is a perturbation approach developed by Kierlik and Rosinberg [Phys. Rev. A 44, 5025 (1991)PLRAAN1050-294710.1103/PhysRevA.44.5025] and Rosenfeld [J. Chem. Phys. 98, 8126 (1993)JCPSA60021-960610.1063/1.464569], where the full free-energy functional is Taylor-expanded around a bulk (homogeneous) reference fluid. Here, it is shown that this functional fails to satisfy the contact density theorem because it also fails to satisfy the known low-density limit. When the functional is corrected to satisfy this limit, a corrected bulk pressure is derived and it is shown that with this pressure both the contact density theorem and the Gibbs adsorption theorem are satisfied.

  5. Hybrid Neuroprosthesis for the Upper Limb: Combining Brain-Controlled Neuromuscular Stimulation with a Multi-Joint Arm Exoskeleton.

    Science.gov (United States)

    Grimm, Florian; Walter, Armin; Spüler, Martin; Naros, Georgios; Rosenstiel, Wolfgang; Gharabaghi, Alireza

    2016-01-01

    Brain-machine interface-controlled (BMI) neurofeedback training aims to modulate cortical physiology and is applied during neurorehabilitation to increase the responsiveness of the brain to subsequent physiotherapy. In a parallel line of research, robotic exoskeletons are used in goal-oriented rehabilitation exercises for patients with severe motor impairment to extend their range of motion (ROM) and the intensity of training. Furthermore, neuromuscular electrical stimulation (NMES) is applied in neurologically impaired patients to restore muscle strength by closing the sensorimotor loop. In this proof-of-principle study, we explored an integrated approach for providing assistance as needed to amplify the task-related ROM and the movement-related brain modulation during rehabilitation exercises of severely impaired patients. For this purpose, we combined these three approaches (BMI, NMES, and exoskeleton) in an integrated neuroprosthesis and studied the feasibility of this device in seven severely affected chronic stroke patients who performed wrist flexion and extension exercises while receiving feedback via a virtual environment. They were assisted by a gravity-compensating, seven degree-of-freedom exoskeleton which was attached to the paretic arm. NMES was applied to the wrist extensor and flexor muscles during the exercises and was controlled by a hybrid BMI based on both sensorimotor cortical desynchronization (ERD) and electromyography (EMG) activity. The stimulation intensity was individualized for each targeted muscle and remained subthreshold, i.e., induced no overt support. The hybrid BMI controlled the stimulation significantly better than the offline analyzed ERD (p = 0.028) or EMG (p = 0.021) modality alone. Neuromuscular stimulation could be well integrated into the exoskeleton-based training and amplified both the task-related ROM (p = 0.009) and the movement-related brain modulation (p = 0.019). Combining a hybrid BMI with neuromuscular stimulation

  6. Gastric potential difference measurements. The gastric mucosal integrity and function studied with a new method for measurement of the electric potential difference across the stomach wall

    DEFF Research Database (Denmark)

    Højgaard, L

    1991-01-01

    be reduced by allopurinol pretreatment, possibly due to the inhibition of oxygen-derived free radical formation. Gastric PD and pH were measured in volunteers and duodenal ulcer patients during Stroop's color word conflict test, in which mental stress causes sympathetic activation. A PD reduction and a p......H increase were found along with stress induction, thereby indicating an influence of mental stress on stomach mucosal function. It is concluded that gastric PD measurement may be useful in ulcer pathogenetic research, and a sufficient gastric mucosal blood flow is stressed as being important for the mucosal......PD--the electric potential difference across the gastric mucosa--is a variable used to describe the gastric mucosal integrity and function. A new, reliable, and easily applied method for gastric PD measurements corrected for the disturbing liquid junction potentials between gastric juice and the PD...

  7. Clinical usefulness of brain-computer interface-controlled functional electrical stimulation for improving brain activity in children with spastic cerebral palsy: a pilot randomized controlled trial

    Science.gov (United States)

    Kim, Tae-Woo; Lee, Byoung-Hee

    2016-01-01

    [Purpose] Evaluating the effect of brain-computer interface (BCI)-based functional electrical stimulation (FES) training on brain activity in children with spastic cerebral palsy (CP) was the aim of this study. [Subjects and Methods] Subjects were randomized into a BCI-FES group (n=9) and a functional electrical stimulation (FES) control group (n=9). Subjects in the BCI-FES group received wrist and hand extension training with FES for 30 minutes per day, 5 times per week for 6 weeks under the BCI-based program. The FES group received wrist and hand extension training with FES for the same amount of time. Sensorimotor rhythms (SMR) and middle beta waves (M-beta) were measured in frontopolar regions 1 and 2 (Fp1, Fp2) to determine the effects of BCI-FES training. [Results] Significant improvements in the SMR and M-beta of Fp1 and Fp2 were seen in the BCI-FES group. In contrast, significant improvement was only seen in the SMR and M-beta of Fp2 in the control group. [Conclusion] The results of the present study suggest that BCI-controlled FES training may be helpful in improving brain activity in patients with cerebral palsy and may be applied as effectively as traditional FES training. PMID:27799677

  8. Effectiveness of Functional Electrical Stimulation in Improving Clinical Outcomes in the Upper Arm following Stroke: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Amir K. Vafadar

    2015-01-01

    Full Text Available Background. Different therapeutic methods are being used to prevent or decrease long-term impairments of the upper arm in stroke patients. Functional electrical stimulation (FES is one of these methods, which aims to stimulate the nerves of the weakened muscles so that the resulting muscle contractions resemble those of a functional task. Objectives. The objective of this study was to review the evidence for the effect of FES on (1 shoulder subluxation, (2 pain, and (3 upper arm motor function in stroke patients, when added to conventional therapy. Methods. From the 727 retrieved articles, 10 (9 RCTs, 1 quasi-RCT were selected for final analysis and were rated based on the PEDro (Physiotherapy Evidence Database scores and the Sackett’s levels of evidence. A meta-analysis was performed for all three considered outcomes. Results. The results of the meta-analyses showed a significant difference in shoulder subluxation in experimental groups compared to control groups, only if FES was applied early after stroke. No effects were found on pain or motor function outcomes. Conclusion. FES can be used to prevent or reduce shoulder subluxation early after stroke. However, it should not be used to reduce pain or improve upper arm motor function after stroke.

  9. Electricity Customers

    Science.gov (United States)

    This page discusses key sectors and how they use electricity. Residential, commercial, and industrial customers each account for roughly one-third of the nation’s electricity use. The transportation sector also accounts for a small fraction of electricity.

  10. Functional electrical stimulation cycling does not improve mobility in people with acquired brain injury and its effects on strength are unclear: a randomised trial

    Directory of Open Access Journals (Sweden)

    Davide G de Sousa

    2016-10-01

    Full Text Available Question: Does 4 weeks of active functional electrical stimulation (FES cycling in addition to usual care improve mobility and strength more than usual care alone in people with a sub-acute acquired brain injury caused by stroke or trauma? Design: Multi centre, randomised, controlled trial. Participants: Forty patients from three Sydney hospitals with recently acquired brain injury and a mean composite strength score in the affected lower limb of 7 (SD 5 out of 20 points. Intervention: Participants in the experimental group received an incremental, progressive, FES cycling program five times a week over a 4-week period. All participants received usual care. Outcome measures: Outcome measures were taken at baseline and at 4 weeks. Primary outcomes were mobility and strength of the knee extensors of the affected lower limb. Mobility was measured with three mobility items of the Functional Independence Measure and strength was measured with a hand-held dynamometer. Secondary outcomes were strength of the knee extensors of the unaffected lower limb, strength of key muscles of the affected lower limb and spasticity of the affected plantar flexors. Results: All but one participant completed the study. The mean between-group differences for mobility and strength of the knee extensors of the affected lower limb were –0.3/21 points (95% CI –3.2 to 2.7 and 7.5 Nm (95% CI –5.1 to 20.2, where positive values favoured the experimental group. The only secondary outcome that suggested a possible treatment effect was strength of key muscles of the affected lower limb with a mean between-group difference of 3.0/20 points (95% CI 1.3 to 4.8. Conclusion: Functional electrical stimulation cycling does not improve mobility in people with acquired brain injury and its effects on strength are unclear. Trial registration: ACTRN12612001163897. [de Sousa DG, Harvey LA, Dorsch S, Leung J, Harris W (2016 Functional electrical stimulation cycling does not improve

  11. Comment on "Ion distribution function in a plasma with uniform electric field" [Phys. Plasmas 19, 113703 (2012)].

    Science.gov (United States)

    Mustafaev, Alex; Sukhomlinov, Vladimir; Timofeev, Nikolay

    2016-08-01

    The comparison between experimental data of ion distribution function at the parent gas plasma obtained by the authors and results of calculations presented by Lampe et al. are considered. It is shown that the experimental and calculated angular distributions of ions in the case at least of argon differ considerably. The analysis of Lampe et al. assumptions showed that the main reasons of these discrepancies were the assumptions of ion distribution function independence on field orientation and independence of charge exchange cross-section on the relative velocity of ion and atom.

  12. Early application of percutaneous neuromuscular electric stimulation in interfering motor function of limbs and difference in temperature of axilla of patients with ischemic stroke

    Institute of Scientific and Technical Information of China (English)

    Zhenhui Jiang; Siyi Yin; Na Bi; Xiang He; Fang Qu

    2006-01-01

    BACKGROUND: Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke.OBJECTIVE: To observe the effect of percutaneous neuromuscular electric stimulation (PNES) on difference in temperature of axilla and analyze the relationship between function of limbs and difference in temperature of axilla.DESIGN: Randomized grouping and controlled observation.SETTING: Department of Neurology, General Hospital of Shenyang Military Area Command of Chinese PLA.PARTICIPANTS: Sixty patients with ischemic stroke were selected from Neurological Department of General Hospital of Shenyang Military Area Command of Chinese PLA from January to June 2003. All cases were diagnosed with clinical diagnosis criteria of ischemic stroke established by the Fourth Chinese Classification of Cerebrovasular Disease and CT examination and received neuromuscular electric stimulation (NES). Patients were randomly divided into control group and treatment group with 30 in each group.METHODS: Control group: Patients received routinely neurological therapy. Treatment group: Except routine therapy, patients suffered from NES at 48 hours after hospitalization. NMT-91 NES equipment was used to stimulated injured limbs with Iow frequency once 30 minutes a day in total of 10 times a course, especially extensor muscle of upper limb and flexor muscle of lower limb. Prescription of hemiplegia was internally decided by equipment with the output frequency of 200 Hz. Intensity of electric output could cause muscle contraction.The therapy needed two or three courses. Temperature of bilateral axilla was measured every day to calculate the difference with the formula of (temperature of axilla on the injured side - temperature of axilla on the healthy side). Motor function of limbs was measured with FugI-Meyer Motor Assessment (FMA) during hospitalization and at 2 and 4 hours after hospitalization. Among 90 points, upper and lower limb function was 54

  13. Direct electric current treatment modifies mitochondrial function and lipid body content in the A549 cancer cell line.

    Science.gov (United States)

    Holandino, Carla; Teixeira, Cesar Augusto Antunes; de Oliveira, Felipe Alves Gomes; Barbosa, Gleyce Moreno; Siqueira, Camila Monteiro; Messeder, Douglas Jardim; de Aguiar, Fernanda Silva; da Veiga, Venicio Feo; Girard-Dias, Wendell; Miranda, Kildare; Galina, Antonio; Capella, Marcia Alves Marques; Morales, Marcelo Marcos

    2016-10-01

    Electrochemical therapy (EChT) entails treatment of solid tumors with direct electric current (DC). This work evaluated the specific effects of anodic flow generated by DC on biochemical and metabolic features of the A549 human lung cancer cell line. Apoptosis was evaluated on the basis of caspase-3 activity and mitochondrial transmembrane potential dissipation. Cell morphology was analyzed using transmission electron microscopy, and lipid droplets were studied through morphometric analysis and X-ray qualitative elemental microanalysis. High-resolution respirometry was used to assess mitochondrial respiratory parameters. Results indicated A549 viability decreased in a dose-dependent manner with a prominent drop between 18 and 24h after treatment (p<0.001), together with a two-fold increase in caspase-3 activity. AF-treatment induced a significantly increase (p<0.01) in the cell number with disrupted mitochondrial transmembrane potential. Furthermore, treated cells demonstrated important ultrastructural mitochondria damage and a three-fold increase in the cytoplasmic lipid bodies' number, quantified by morphometrical analyses. Conversely, 24h after treatment, the cells presented a two-fold increase of residual oxygen consumption, accounting for 45.3% of basal oxygen consumption. These results show remarkable alterations promoted by anodic flow on human lung cancer cells which are possibly involved with the antitumoral effects of EChT.

  14. Effects of ultraviolet irradiation, pulsed electric field, hot water and ethanol vapours treatment on functional properties of mung bean sprouts.

    Science.gov (United States)

    Goyal, Ankit; Siddiqui, Saleem; Upadhyay, Neelam; Soni, Jyoti

    2014-04-01

    The present investigation was conducted with the objective to study the effects of various treatments and storage conditions on ascorbic acid, total phenols, antioxidant activity and polyphenol oxidase activity of mung bean sprouts. The sprouts subjected to various treatments viz., pulsed electric field (PEF) (10,000 V for 10 s), hot water dip (HWD) (50 °C for 2 min), ethanol vapours (1 h) and UV-Irradiation (10 kJm(-2) in laminar flow chamber for 1 h); and then stored at room (25 ± 1 °C) and low (7 ± 1 °C) temperature conditions. The sprouts were analyzed regularly at 24 h interval till end of shelf life. Different treatments given to sprouts resulted in differential effect on various parameters. The ascorbic acid, total phenols and antioxidant activity were highest in ethanol vapours treated sprouts. There was a general decrease in polyphenol oxidase activity by various treatments. During storage ascorbic acid, total phenols and antioxidant activity of sprouts first increased and then decreased significantly, however, for polyphenol oxidase activity a progressive increase with increase in storage period was observed. The trends were similar at room and low temperature storage conditions. Thus, it can be concluded that the ethanol vapours significantly improved the ascorbic acid content, total phenols and antioxidant activity of mung bean sprouts, both at room as well as low temperature conditions of storage.

  15. Multiplexed Electrochemical Immunoassay of Phosphorylated Proteins Based on Enzyme-Functionalized Gold Nanorod Labels and Electric Field-Driven Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Du, Dan; Wang, Jun; Lu, Donglai; Dohnalkova, Alice; Lin, Yuehe

    2011-09-09

    A multiplexed electrochemical immunoassay integrating enzyme amplification and electric field-driven strategy was developed for fast and sensitive quantification of phosphorylated p53 at Ser392 (phospho-p53 392), Ser15 (phospho-p53 15), Ser46 (phospho-p53 46) and total p53 simultaneously. The disposable sensor array has four spatially separated working electrodes and each of them is modified with different capture antibody, which enables simultaneous immunoassay to be conducted without cross-talk between adjacent electrodes. The enhanced sensitivity was achieved by multi-enzymes amplification strategy using gold nanorods (AuNRs) as nanocarrier for co-immobilization of horseradish peroxidase (HRP) and detection antibody (Ab2) at high ratio of HRP/Ab2, which produced an amplified electrocatalytic response by the reduction of HRP oxidized thionine in the presence of hydrogen peroxide. The immunoreaction processes were accelerated by applying +0.4 V for 3 min and then -0.2 V for 1.5 min, thus the whole sandwich immunoreactions could be completed in less than 5 min. The disposable immunosensor array shows excellent promise for clinical screening of phosphorylated proteins and convenient point-of-care diagnostics.

  16. Differential cellular FGF-2 upregulation in the rat facial nucleus following axotomy, functional electrical stimulation and corticosterone: a possible therapeutic target to Bell's palsy

    Directory of Open Access Journals (Sweden)

    Oliveira Gabriela P

    2010-11-01

    Full Text Available Abstract Background The etiology of Bell's palsy can vary but anterograde axonal degeneration may delay spontaneous functional recovery leading the necessity of therapeutic interventions. Corticotherapy and/or complementary rehabilitation interventions have been employed. Thus the natural history of the disease reports to a neurotrophic resistance of adult facial motoneurons leading a favorable evolution however the related molecular mechanisms that might be therapeutically addressed in the resistant cases are not known. Fibroblast growth factor-2 (FGF-2 pathway signaling is a potential candidate for therapeutic development because its role on wound repair and autocrine/paracrine trophic mechanisms in the lesioned nervous system. Methods Adult rats received unilateral facial nerve crush, transection with amputation of nerve branches, or sham operation. Other group of unlesioned rats received a daily functional electrical stimulation in the levator labii superioris muscle (1 mA, 30 Hz, square wave or systemic corticosterone (10 mgkg-1. Animals were sacrificed seven days later. Results Crush and transection lesions promoted no changes in the number of neurons but increased the neurofilament in the neuronal neuropil of axotomized facial nuclei. Axotomy also elevated the number of GFAP astrocytes (143% after crush; 277% after transection and nuclear FGF-2 (57% after transection in astrocytes (confirmed by two-color immunoperoxidase in the ipsilateral facial nucleus. Image analysis reveled that a seven days functional electrical stimulation or corticosterone led to elevations of FGF-2 in the cytoplasm of neurons and in the nucleus of reactive astrocytes, respectively, without astrocytic reaction. Conclusion FGF-2 may exert paracrine/autocrine trophic actions in the facial nucleus and may be relevant as a therapeutic target to Bell's palsy.

  17. APPLICATION OF TRANSCUTANEOUS ELECTRICAL STIMULATION ON LOWER LIMB ACUPOINTS AS AN IMPORTANT ADJUNCTIVE TOOL IN STROKE REHABILITATION PROGRAM & ITS EFFECTS ON SPASTICITY AND FUNCTIONAL ABILITY

    Directory of Open Access Journals (Sweden)

    Chandan Kumar

    2013-08-01

    Full Text Available Background: There is increasing evidence of neural plastic changes associated with specific training that isgoal-directed and requires special attention with practice. Sensory input by Transcutaneous electrical stimulation(TENS on acupoints and task related training (TRT induces recovery of lower limb function in patients afterstroke. There are very few studies which show the effectiveness and importance of sensory stimulation throughacupoints, therefore the purpose of the current study is to evaluate the effectiveness of TENS on acupointswhen applied with other rehabilitation program on reducing spasticity and improving lower limb function insubjects after sub-acute stroke. Materials and Methods: Thirty subjects with sub-acute stroke of either sideincluding both male and female participated in randomised clinical trial. Both group received TRT along withconventional physiotherapy program. TENS on acupoints was given in subjects of experimental group alongwith TRT and conventional program to evaluate the effectiveness of TENS. Measurement of spasticity was doneby Modified Ashworth Scale (MAS, functional ability was measured by Dynamic Gait index (DGI and Timed up& Go (TUG test. All the measurements were done before and after 5 weeks intervention. Result: A significantreduction in spasticity measured by MAS (p=0.03 and relevant improvement in functional ability measured byDGI (p=0.03 and TUG (p=0.04 were observed in experimental group after five weeks intervention.Conclusion: Present study provides an evidence to support the use of TENS on acupoints as an adjunctive toolwith task related training and other rehabilitation program.

  18. Thermal dilepton rate and electrical conductivity: An analysis of vector current correlation functions in quenched lattice QCD

    CERN Document Server

    Ding, H -T; Kaczmarek, O; Karsch, F; Laermann, E; Soeldner, W

    2010-01-01

    We calculate the vector current correlation function for light valence quarks in the deconfined phase of QCD. The calculations have been performed in quenched lattice QCD at T=1.45 Tc for four values of the lattice cut-off on lattices up to size 128^3x48. This allows to perform a continuum extrapolation of the correlation function in the Euclidean time interval tau*T -in [0.2, 0.5], which extends to the largest temporal separations possible at finite temperature, to better than 1% accuracy. In this interval, at the value of the temperature investigated, we find that the vector correlation function never deviates from the free correlator for massless quarks by more than 9%. We also determine the first two non-vanishing thermal moments of the vector meson spectral function. The second thermal moment deviates by less than 7% from the free value. With these constraints, we then proceed to extract information on the spectral representation of the vector correlator and discuss resulting consequences for the electri...

  19. Produksi Functionally Graded Material (FGM dari Hydroxyapatite-Serat Sutra untuk Aplikasi di Bidang Biomaterial dengan Teknik Pulse Electric Current Sintering

    Directory of Open Access Journals (Sweden)

    Tjokorda Gde Tirta Nindhia

    2006-01-01

    Full Text Available This research is intended to produce functionally graded material (FGM of Hydroxyapatite (Hap-silk fibroin by pulse electric current sintering in facing the need in biomaterial application. The sample is created with 4 layers with the thickness for each layer is 0,625 mm, so that the total samples thickness become 2.5mm, with diameter 15 mm. The carbon die is used to compact the sample. The composition of lower layer is 100% silk fibroin, after that 90% silk fibroin +10% Hap, third layer was 80% silk fibroin + 20%Hap, and 70% silk fibroin +30% Hap for the upper layer. The properties of the FGM product was characterized by optical microscope and scanning electron microscope (SEM, three point bend with single-edge beam fracture toughness test (KIC. The grade of the FGM material is proven by using electron probe micro analyzer (EPMA. The value of fracture toughness is 0.45 MPa.m1/2. The sample still can support the load after maximum load is reached. Optical micrograph and SEM, and result from EPMA indicate that the Hap-silk fibroin FGM can be produce perfectly by using the method that is introduced in this research. Abstract in Bahasa Indonesia : Penelitian ini bertujuan memproduksi functionally graded material (FGM dari hydroxyapatite (Hap-serat sutra, melalui teknik pulse electric current sintering untuk memenuhi tantangan kebutuhan akan bahan jenis ini untuk digunakan dibidang biomaterial. Benda uji terdiri dari 4 lapis dengan ketebalan sama untuk tiap lapisnya sehingga tebal total menjadi 2.5 mm dengan diameter 15 mm. Komposisi lapisan paling bawah adalah 100% serat sutra, setelah itu 90% serat sutra + 10% Hap. Lapisan ketiga dengan komposisi 80% serat sutra + 20% Hap, dan 70% serat sutra + 30% Hap untuk lapisan paling atas. Perilaku produk FGM ini dikarakterisasikan dengan mikroskop optik, mikroskop electron, uji ketangguhan retak three point bend with single-edge. Gradasi (grade dari FGM dibuktikan dengan electron probe micro analyzer (EPMA

  20. Static and Modal Analysis of Multi-function Electric Vehicle Frame%多功能电动车车架静态及模态分析

    Institute of Scientific and Technical Information of China (English)

    万国睿; 琚立颖; 龙海洋

    2016-01-01

    将数字模型导入ANSYS中,利用ANSYS/Workbench对多功能电动车车底架进行工况下静力和模态分析,验证车架的力学性能符合设计要求,并提出了改进意见,为唐山电动汽车重点实验室研制多功能电动车提供参考和理论依据。此外,还通过划分网格实验初步验证网格尺寸与模型对车架有限元计算结果的影响。%Frame is the mounting base of the multi-function electric vehicle ,bearing complicated force and tosional moment .The performance of vehicle is related to the frame directly .Based on ANSYS the large-scale finite element analysis software ,the static analysis and modal analysis of the frame under working condition were conducted .The results showed the mechanical properties of the frame could meet the design requirement .Valuable suggestions were taken by Tangshan Electric Vehicle Key Laboratory .The influence of meshing on the calculation results in finite element analysis was verified preliminarily .

  1. The Effect of NeuroMuscular Electrical Stimulation on Quadriceps Strength and Knee Function in Professional Soccer Players: Return to Sport after ACL Reconstruction

    Directory of Open Access Journals (Sweden)

    J. Taradaj

    2013-01-01

    Full Text Available The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction on the quadriceps muscle. The 80 participants (NMES = 40, control = 40 received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz three times daily (3 hours of break between treatments, 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months were applied. The results of this study show that NMES (in presented parameters in experiment is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741.

  2. The effect of neuromuscular electrical stimulation on quadriceps strength and knee function in professional soccer players: return to sport after ACL reconstruction.

    Science.gov (United States)

    Taradaj, J; Halski, T; Kucharzewski, M; Walewicz, K; Smykla, A; Ozon, M; Slupska, L; Dymarek, R; Ptaszkowski, K; Rajfur, J; Pasternok, M

    2013-01-01

    The aim of this study was to assess the clinical efficacy and safety of NMES program applied in male soccer players (after ACL reconstruction) on the quadriceps muscle. The 80 participants (NMES = 40, control = 40) received an exercise program, including three sessions weekly. The individuals in NMES group additionally received neuromuscular electrical stimulation procedures on both right and left quadriceps (biphasic symmetric rectangular pulses, frequency of impulses: 2500 Hz, and train of pulses frequency: 50 Hz) three times daily (3 hours of break between treatments), 3 days a week, for one month. The tensometry, muscle circumference, and goniometry pendulum test (follow-up after 1 and 3 months) were applied. The results of this study show that NMES (in presented parameters in experiment) is useful for strengthening the quadriceps muscle in soccer athletes. There is an evidence of the benefit of the NMES in restoring quadriceps muscle mass and strength of soccer players. In our study the neuromuscular electrical stimulation appeared to be safe for biomechanics of knee joint. The pathological changes in knee function were not observed. This trial is registered with Australian and New Zealand Clinical Trials Registry ACTRN12613001168741.

  3. Effects of Rare-Earth La2O3 Addition on Microstructures and Electrical Properties of SrTiO3 Varistor-Capacitor Dual Functional Ceramics

    Institute of Scientific and Technical Information of China (English)

    Ji Huiming; Li Cuixia; Meng Hui; Gan Guoyou; Yan Jikang

    2005-01-01

    The effects of rare-earth La2O3 addition on microstructures and electrical properties of SrTiO3 ceramics were investigated. Semiconductor SrTiO3-based voltage-sensing and dielectric dual functional ceramics was prepared by a single step sintering technology in this study, and the effects of the content of La2O3 on characteristics of the product were discussed in terms of microstructures and electrical properties of materials. The results show that SrTiO3-based ceramics doped with La2O3 exhibits more homogeneous grain distribution, greater grain size, and excellent voltage sensing and dielectric characteristics than those without La2O3 doping. The samples doped with 1.1% La2O3 were sintered at 1420 ℃ in N2+C weak reducing atmosphere. The average grain size of the samples doped with La2O3 is 40 μm, the breakdown voltage of 19.7 V*mm-1, the nonlinear exponent of 7.2, and dielectric constant of 22500. The results reveal that final products are suitable to use in low operating voltage.

  4. Monitoring muscle metabolic indexes by time-domain near-infrared spectroscopy during knee flex-extension induced by functional electrical stimulation

    Science.gov (United States)

    Ferrante, Simona; Contini, Davide; Spinelli, Lorenzo; Pedrocchi, Alessandra; Torricelli, Alessandro; Molteni, Franco; Ferrigno, Giancarlo; Cubeddu, Rinaldo

    2009-07-01

    A noninvasive methodology, combining functional electrical stimulation and time-domain near-infrared spectroscopy (TD-NIRS), is developed to verify whether stroke-altered muscular metabolism on postacute patients. Seven healthy subjects and nine postacute stroke patients undergo a protocol of knee flex-extension induced by quadricep electrical stimulation. During the protocol, TD-NIRS measurements are performed on both rectus femoris to investigate whether significant differences arise between able-bodied and stroke subjects and between patients' paretic and healthy legs. During baseline, metabolic parameters do not show any significant differences among subjects. During stimulation, paretic limbs produce a knee angle significantly lower than healthy legs. During recovery, patients' healthy limbs show a metabolic behavior correlated to able-bodied subjects. Instead, the correlation between the metabolic behavior of the paretic and able-bodied legs allows the definition of two patients' subgroups: one highly correlated (R>0.87) and the other uncorrelated (Rmuscle, but the metabolic dysfunction seems to be local and unilateral. It is crucial to enlarge the sample size of the two subgroups before making these preliminary results a general finding.

  5. A density functional study of (17)O, (14)N and (2)H electric field gradient tensors in the real crystalline structure of alpha-glycine.

    Science.gov (United States)

    Behzadi, Hadi; Hadipour, Nasser L; Mirzaei, Mahmoud

    2007-01-01

    A density functional theory (DFT) study was carried out to calculate (17)O, (14)N and (2)H electric field gradient (EFG) tensors in accurate neutron diffraction structures of alpha-glycine at 288 and 427 K. B3LYP is the used method and 6-311+G(*) and 6-311++G(**) are the basis sets in the calculations of EFG tensors at the sites of (17)O, (14)N and (2)H nuclei in the monomer and the octameric cluster of alpha-glycine at two temperatures. Quadrupole coupling constants and asymmetry parameters are the converted parameters of calculated EFG tensors to experimentally measurable ones. The calculated results of monomer and the target molecule in octameric cluster reveal that hydrogen-bonding interactions play an important role in the crystalline structure of alpha-glycine where the results of the target molecule in octameric cluster are in good agreement with the experiments.

  6. Effects of transcutaneous electrical nerve stimulation on pain, walking function, respiratory muscle strength and vital capacity in kidney donors: a protocol of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Galli Thiago Tafarel

    2013-01-01

    Full Text Available Abstract Background Pain is a negative factor in the recovery process of postoperative patients, causing pulmonary alterations and complications and affecting functional capacity. Thus, it is plausible to introduce transcutaneous electrical nerve stimulation (TENS for pain relief to subsequently reduce complications caused by this pain in the postoperative period. The objective of this paper is to assess the effects of TENS on pain, walking function, respiratory muscle strength and vital capacity in kidney donors. Methods/design Seventy-four patients will be randomly allocated into 2 groups: active TENS or placebo TENS. All patients will be assessed for pain intensity, walk function (Iowa Gait Test, respiratory muscle strength (maximal inspiratory pressure and maximal expiratory pressure and vital capacity before and after the TENS application. The data will be collected by an assessor who is blinded to the group allocation. Discussion This study is the first to examine the effects of TENS in this population. TENS during the postoperative period may result in pain relief and improvements in pulmonary tests and mobility, thus leading to an improved quality of life and further promoting organ donation. Trial registration Registro Brasileiro de Ensaios Clinicos (ReBEC, number RBR-8xtkjp.

  7. Functional morphology of jaw trabeculation in the lesser electric ray Narcine brasiliensis, with comments on the evolution of structural support in the Batoidea.

    Science.gov (United States)

    Dean, Mason N; Huber, Daniel R; Nance, Holly A

    2006-10-01

    The design of minimum-weight structures that retain their integrity under dynamic loading regimes has long challenged engineers. One solution to this problem found in both human and biological design is the optimization of weight and strength by hollowing a structure and replacing its inner core with supportive struts. In animals, this design is observed in sand dollar test, avian beak, and the cancellous bone of tetrapod limbs. Additionally, within the elasmobranch fishes, mineralized trabeculae (struts) have been reported in the jaws of durophagous myliobatid stingrays (Elasmobranchii: Batoidea), but were believed to be absent in basal members of the batoid clade. This study, however, presents an additional case of batoid trabeculation in the lesser electric ray, Narcine brasiliensis (Torpediniformes). The trabeculae in these species likely play different functional roles. Stingrays use their reinforced jaws to crush bivalves, yet N. brasiliensis feeds by ballistically protruding its jaws into the sediment to capture polychaetes. In N. brasiliensis, trabeculae are localized to areas likely to experience the highest load: the quadratomandibular jaw joints, hyomandibular-cranial joint, and the thinnest sections of the jaws immediately lateral to the symphyses. However, the supports perform different functions dependent on location. In regions where the jaws are loaded transversely (as in durophagous rays), "load leading" trabeculae distribute compressive forces from the cortex through the lumen of the jaws. In the parasymphyseal regions of the jaws, "truss" trabeculae form cross-braces perpendicular to the long axes of the jaws. At peak protrusion, the jaw arch is medially compressed and the jaw loaded axially such that these trabeculae are positioned to resist buckling associated with excavation forces. "Truss" trabeculae function to maintain the second moment of area in the thinnest regions of the jaws, illustrating a novel function for batoid trabeculation. Thus

  8. The course and the anatomo-functional relationships of the optic radiation: a combined study with 'post mortem' dissections and 'in vivo' direct electrical mapping.

    Science.gov (United States)

    Sarubbo, Silvio; De Benedictis, Alessandro; Milani, Paola; Paradiso, Beatrice; Barbareschi, Mattia; Rozzanigo, Umbero; Colarusso, Enzo; Tugnoli, Valeria; Farneti, Marco; Granieri, Enrico; Duffau, Hugues; Chioffi, Franco

    2015-01-01

    Even if different dissection, tractographic and connectivity studies provided pure anatomical evidences about the optic radiations (ORs), descriptions of both the anatomical structure and the anatomo-functional relationships of the ORs with the adjacent bundles were not reported. We propose a detailed anatomical and functional study with 'post mortem' dissections and 'in vivo' direct electrical stimulation (DES) of the OR, demonstrating also the relationships with the adjacent eloquent bundles in a neurosurgical 'connectomic' perspective. Six human hemispheres (three left, three right) were dissected after a modified Klingler's preparation. The anatomy of the white matter was analysed according to systematic and topographical surgical perspectives. The anatomical results were correlated to the functional responses collected during three resections of tumours guided by cortico-subcortical DES during awake procedures. We identified two groups of fibres forming the OR. The superior component runs along the lateral wall of the occipital horn, the trigone and the supero-medial wall of the temporal horn. The inferior component covers inferiorly the occipital horn and the trigone, the lateral wall of the temporal horn and arches antero-medially to form the Meyer's Loop. The inferior fronto-occipital fascicle (IFOF) covers completely the superior OR along its entire course, as confirmed by the subcortical DES. The inferior longitudinal fascicle runs in a postero-anterior and inferior direction, covering the superior OR posteriorly and the inferior OR anteriorly. The IFOF identification allows the preservation of the superior OR in the anterior temporal resection, avoiding post-operative complete hemianopia. The identification of the superior OR during the posterior temporal, inferior parietal and occipital resections leads to the preservation of the IFOF and of the eloquent functions it subserves. The accurate knowledge of the OR course and the relationships with the

  9. 脑控:基于脑-机接口的人机融合控制%Brain Control: Human-computer Integration Control Based on Brain-computer Interface

    Institute of Scientific and Technical Information of China (English)

    王行愚; 金晶; 张宇; 王蓓

    2013-01-01

    近年来,一类被称之为脑控的新型控制系统发展迅速,这是一种基于脑-机接口(Brain-computer interface,BCI)的人机融合控制系统,也是一种基于人的意念和思维的控制系统.脑控系统己被成功应用于残疾人的生活辅助、中风病人和损伤肢体的康复训练、操作员状态的实时监控、游戏娱乐和智能家居等广泛的领域.本文在简要介绍了脑控的研究背景、基本原理、系统结构和发展概况的基础上,着重对脑电信号(Electroencephalogram,EEG)模式、控制信号转换算法和应用系统研究等主要问题的研究现状,进行了较为详细的论述和分析,并探讨了进一步研究的方向和思路.最后对脑控的未来发展方向和应用前景进行了分析和展望.%Recently, a new system called brain control system has been developed rapidly. Brain control system is a human-computer integration control system based on brain-computer interface (BCI), which relies on human's ideas and thinking. Brain control system has been successfully applied in wide fields, assisting disabled patients daily life, training patients with stroke or limb injury, monitoring the status of human operator, as well as entertainment and smart house etc. In this paper, the background, basic principle, system structure and developments are firstly introduced briefly. The current research status focusing on the problems of electroencephalogram (EEG) signal pattern, control signal transfer algorithm and system application is summarized and analyzed in detail. The further research direction and thoughts are discussed. Finally, the future development of brain control is analyzed and prospects are given.

  10. 临床偏瘫病人早期上肢功能性电刺激屈肌和伸肌与伸肌功能性电刺激的比较%Clinical patients with hemiplegia early upper limb functional electrical stimulationflexor and extensor compared with extensor functional electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    杨一帆; 姚敬宇; 莫天才; 杨维维

    2015-01-01

    objective to patients with hemiplegia early upper limb functional electrical stimulation fiexor and extensor was compared with the extensor functional electrical stimulation.Methods acute onset in patients with hemiplegia, hemiplegic side body let in phase delay of 20 patients with hemiplegia patients at random points in the control group (n = 10) and observation group (n = 10), the control group to maintain nerve functional electrical stimulation upper limb muscle of wrist and the reach anconeus and function of routine rehabilitation training, observation group nerve functional electrical stimulation upper limbfiexor muscle of wrist and elbow fiexion with fiexor muscle tension change stimulation wrist, elbow muscle group.Before and 3 weeks after treatment with modified ashworth (Mas), concise fugl - Meyer evaluation form, out of assessment.results after treatment, no obvious difference was found between two groups of Mas, concise fugl - Meyer exercise evaluation form, out the assessment, the observation group statistically significant meaningful (P < 0.05).conclusion early fiexor functional electrical stimulation out instead of extensor muscle tension stimulation, for upper hand function in patients with hemiplegia rehabilitation and separatist movements appear faster.%目的:早期偏瘫病人上肢功能性电刺激屈肌和伸肌与伸肌功能性电刺激的比较。方法急性期发病偏瘫患者,偏瘫侧肢体任处于迟缓期的偏瘫病人20例,随机分对照组(n=10)和观察组(n=10),对照组维持神经功能性电刺激上肢伸腕肌及伸肘肌和常规康复功能训练,观察组神经功能电刺激上肢屈腕肌及屈肘肌随着屈肌张力改变刺激伸腕、伸肘肌群。治疗前及治疗3周后采用改良ashworth(Mas)、简明fugl-Meyer运动评定表、Brunnstrom进行评定。结果治疗后,两组Mas无明显差异,简明fugl-Meyer运动评定表、Brunnstrom运动评定观察组有统计学差异,有意义(P<0

  11. Wide-pulse electrical stimulation to an intrinsic foot muscle induces acute functional changes in forefoot-rearfoot coupling behaviour during walking.

    Science.gov (United States)

    James, D C; Chesters, T; Sumners, D P; Cook, D P; Green, D A; Mileva, K N

    2013-05-01

    Interventions for strengthening intrinsic foot muscles may be beneficial for rehabilitation from overuse injuries. In this study the acute effects of high-frequency, low-intensity wide-pulse electrical stimulation (WPS) over an intrinsic muscle on subsequent foot function during walking was assessed in healthy participants. WPS was delivered to the m. abductor hallucis (m.AH) of the non-dominant foot during relaxed standing. 3-dimensional forefoot (FF)--rearfoot (RF) coordination was quantified with a vector coding technique within separate periods of the stance phase to study WPS functional effects on foot motion. 4 types of coordinative strategies between the FF and RF were interpreted and compared PRE-to-POST-WPS for both the experimental and control feet. Bilateral electromyography (EMG) from m.AH was analysed during the intervention period for evidence of acute neuromuscular adaptation. The results showed that WPS significantly modulated FF-RF coordination during mid-stance, indicative of a more stable foot. Specifically, a statistically significant increase in FF eversion with concomitant RF inversion in the frontal plane and RF-dominated adduction in the transverse plane was observed. Subject-specific increases in post-stimulus m.AH EMG activation were observed but this was not reflected in an overall group effect. It is concluded that the structural integrity of the foot during walking is enhanced following an acute session of WPS and that this mechanical effect is most likely due to stimulation induced post-tetanic potentiation of synaptic transmission.

  12. 3-D electrical resistivity structure based on geomagnetic transfer functions exploring the features of arc magmatism beneath Kyushu, Southwest Japan Arc

    Science.gov (United States)

    Hata, Maki; Uyeshima, Makoto; Handa, Shun; Shimoizumi, Masashi; Tanaka, Yoshikazu; Hashimoto, Takeshi; Kagiyama, Tsuneomi; Utada, Hisashi; Munekane, Hiroshi; Ichiki, Masahiro; Fuji-ta, Kiyoshi

    2017-01-01

    Our 3-D electrical resistivity model clearly detects particular subsurface features for magmatism associated with subduction of the Philippine Sea Plate (PSP) in three regions: a southern and a northern volcanic region, and a nonvolcanic region on the island of Kyushu. We apply 3-D inversion analyses for geomagnetic transfer function data of a short-period band, in combination with results of a previous 3-D model that was determined by using Network-Magnetotelluric response function data of a longer-period band as an initial model in the present inversion to improve resolution at shallow depths; specifically, a two-stage inversion is used instead of a joint inversion. In contrast to the previous model, the presented model clearly reveals a conductive block on the back-arc side of Kirishima volcano at shallow depths of 50 km; the block is associated with hydrothermal fluids and hydrothermal alteration zones related to the formation of epithermal gold deposits. A second feature revealed by the model is another conductive block regarded as upwelling fluids, extending from the upper surface of the PSP in the mantle under Kirishima volcano in the southern volcanic region. Third, a resistive crustal layer, which confines the conductive block in the mantle, is distributed beneath the nonvolcanic region. Fourth, our model reveals a significant resistive block, which extends below the continental Moho at the fore-arc side of the volcanic front and extends into the nonvolcanic region in central Kyushu.

  13. Neuro-fuzzy decoding of sensory information from ensembles of simultaneously recorded dorsal root ganglion neurons for functional electrical stimulation applications

    Science.gov (United States)

    Rigosa, J.; Weber, D. J.; Prochazka, A.; Stein, R. B.; Micera, S.

    2011-08-01

    Functional electrical stimulation (FES) is used to improve motor function after injury to the central nervous system. Some FES systems use artificial sensors to switch between finite control states. To optimize FES control of the complex behavior of the musculo-skeletal system in activities of daily life, it is highly desirable to implement feedback control. In theory, sensory neural signals could provide the required control signals. Recent studies have demonstrated the feasibility of deriving limb-state estimates from the firing rates of primary afferent neurons recorded in dorsal root ganglia (DRG). These studies used multiple linear regression (MLR) methods to generate estimates of limb position and velocity based on a weighted sum of firing rates in an ensemble of simultaneously recorded DRG neurons. The aim of this study was to test whether the use of a neuro-fuzzy (NF) algorithm (the generalized dynamic fuzzy neural networks (GD-FNN)) could improve the performance, robustness and ability to generalize from training to test sets compared to the MLR technique. NF and MLR decoding methods were applied to ensemble DRG recordings obtained during passive and active limb movements in anesthetized and freely moving cats. The GD-FNN model provided more accurate estimates of limb state and generalized better to novel movement patterns. Future efforts will focus on implementing these neural recording and decoding methods in real time to provide closed-loop control of FES using the information extracted from sensory neurons.

  14. Thermal conductivity and Kapitza resistance of cyanate ester epoxy mix and tri-functional epoxy electrical insulations at superfluid helium temperature

    CERN Document Server

    Pietrowicz, S; Jones, S; Canfer, S; Baudouy, B

    2012-01-01

    In the framework of the European Union FP7 project EuCARD, two composite insulation systems made of cyanate ester epoxy mix and tri-functional epoxy (TGPAP-DETDA) with S-glass fiber have been thermally tested as possible candidates to be the electrical insulation of 13 T Nb3Sn high field magnets under development for this program. Since it is expected to be operated in pressurized superfluid helium at 1.9 K and 1 atm, the thermal conductivity and the Kapitza resistance are the most important input parameters for the thermal design of this type of magnet and have been determined in this study. For determining these thermal properties, three sheets of each material with different thicknesses varying from 245 μm to 598 μm have been tested in steady-state condition in the temperature range of 1.6 K - 2.0 K. The thermal conductivity for the tri-functional epoxy (TGPAP-DETDA) epoxy resin insulation is found to be k=[(34.2±5.5).T-(16.4±8.2)]×10-3 Wm-1K-1 and for the cyanate ester epoxy k=[(26.8±4.8).T- (9.6±5...

  15. Electric Power

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ China Council for the Promotion of International Trade Electric Power Industry Office (CCPIT Electric Power), one of the pro-fessional industrial branches of China Council for the Promotion of International Trade (CCPIT), was established in 2006.

  16. Effects of Action Observational Training Plus Brain-Computer Interface-Based Functional Electrical Stimulation on Paretic Arm Motor Recovery in Patient with Stroke: A Randomized Controlled Trial.

    Science.gov (United States)

    Kim, TaeHoon; Kim, SeongSik; Lee, ByoungHee

    2016-03-01

    The purpose of this study was to investigate whether action observational training (AOT) plus brain-computer interface-based functional electrical stimulation (BCI-FES) has a positive influence on motor recovery of paretic upper extremity in patients with stroke. This was a hospital-based, randomized controlled trial with a blinded assessor. Thirty patients with a first-time stroke were randomly allocated to one of two groups: the BCI-FES group (n = 15) and the control group (n = 15). The BCI-FES group administered to AOT plus BCI-FES on the paretic upper extremity five times per week during 4 weeks while both groups received conventional therapy. The primary outcomes were the Fugl-Meyer Assessment of the Upper Extremity, Motor Activity Log (MAL), Modified Barthel Index and range of motion of paretic arm. A blinded assessor evaluated the outcomes at baseline and 4 weeks. All baseline outcomes did not differ significantly between the two groups. After 4 weeks, the Fugl-Meyer Assessment of the Upper Extremity sub-items (total, shoulder and wrist), MAL (MAL-Activity of Use and Quality of Movement), Modified Barthel Index and wrist flexion range of motion were significantly higher in the BCI-FES group (p stroke rehabilitation. The limitations of the study are that subjects had a certain limited level of upper arm function, and the sample size was comparatively small; hence, it is recommended that future large-scale trials should consider stratified and lager populations according to upper arm function.

  17. Efficacy of functional electrical stimulation on the lower limb function and walking ability of hemiplegic stroke patients%功能性电刺激对偏瘫患者下肢功能及步态的影响

    Institute of Scientific and Technical Information of China (English)

    许佳; 胡世红; 凌晴; 何嫱; 陈丽丹; 陈庆珍

    2015-01-01

    目的:观察功能性电刺激对脑卒中偏瘫患者下肢运动功能及步态的影响。方法:60例脑卒中偏瘫患者分成观察组和对照组,每组30例。对照组采用常规康复训练方法,观察组在此基础上增加佩戴步态诱发功能电刺激仪的步态训练,每次20min ,每周5次,持续8周。于治疗前后采用下肢Fugl‐Meyer运动功能评分(FMA)、功能性步行能力分级(FAC )及足印分析法对2组患者进行评定。结果:治疗8周后,2组患者下肢 FM A评分、FAC分级及患侧的平均步长、步宽及步速均较治疗前显著提高(P<0.05),且观察组更高于对照组(P<0.05)。结论:使用功能性电刺激进行步态训练后可进一步改善脑卒中偏瘫患者的下肢运动功能,提高步行能力。%Objective:To investigate the efficacy of functional electrical stimulation on the lower limb motor func‐tion and walking ability of hemiplegic stroke patients .Methods:Sixty hemiplegic stroke patients were randomly di‐vided into a treatment group and a control group (n=30 each) .Both groups were treated with routine rehabilita‐tion ,but the treatment group also undertook gait training with gait triggered functional electrical stimulation .The training was carried out 20 min every day ,5 days every week for 8 weeks .All patients were assessed with the Fugl‐Meyer lower limb assessment (FMA) ,functional ambulation category (FAC) classification and footprint analysis pretreatment and 8 weeks post‐treatment .Results:Eight weeks post‐treatment ,the FMA motor function ,FAC classification and the average values of step length ,stride width and velocity at the affected side in both two groups were significantly increased as compared with those pretreatment ,more significantly in the treatment group than in the control group (P<0 .05) .Conclusions:Gait training with functional electrical stimulation combined with routine rehabilitation training

  18. 3D false color computed tomography for diagnosis and follow-up of permanent denervated human muscles submitted to home-based Functional Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Ugo Carraro

    2015-03-01

    Full Text Available This report outlines the use of a customized false-color 3D computed tomography (CT protocol for the imaging of the rectus femoris of spinal cord injury (SCI patients suffering from complete and permanent denervation, as characterized by complete Conus and Cauda Equina syndrome. This muscle imaging method elicits the progression of the syndrome from initial atrophy to eventual degeneration, as well as the extent to which patients' quadriceps could be recovered during four years of home-based functional electrical stimulation (h-b FES. Patients were pre-selected from several European hospitals and functionally tested by, and enrolled in the EU Commission Shared Cost Project RISE (Contract n. QLG5-CT-2001-02191 at the Department of Physical Medicine, Wilhelminenspital, Vienna, Austria. Denervated muscles were electrically stimulated using a custom-designed stimulator, large surface electrodes, and customized progressive stimulation settings. Spiral CT images and specialized computational tools were used to isolate the rectus femoris muscle and produce 3D and 2D reconstructions of the denervated muscles. The cross sections of the muscles were determined by 2D Color CT, while muscle volumes were reconstructed by 3D Color CT. Shape, volume, and density changes were measured over the entirety of each rectus femoris muscle. Changes in tissue composition within the muscle were visualized by associating different colors to specified Hounsfield unit (HU values for fat, (yellow: [-200; -10], loose connective tissue or atrophic muscle, (cyan: [-9; 40], and normal muscle, fascia and tendons included, (red: [41; 200]. The results from this analysis are presented as the average HU values within the rectus femoris muscle reconstruction, as well as the percentage of these tissues with respect to the total muscle volume. Results from this study demonstrate that h-b FES induces a compliance-dependent recovery of muscle volume and size of muscle fibers, as

  19. Electric drives

    CERN Document Server

    Boldea, Ion

    2005-01-01

    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  20. Electrical contracting

    CERN Document Server

    Neidle, Michael

    2013-01-01

    Electrical Contracting, Second Edition is a nine-chapter text guide for the greater efficiency in planning and completing installations for the design, installation and control of electrical contracts. This book starts with a general overview of the efficient cabling and techniques that must be employed for safe wiring design, as well as the cost estimation of the complete electrical contract. The subsequent chapters are devoted to other electrical contracting requirements, including electronic motor control, lighting, and electricity tariffs. A chapter focuses on the IEE Wiring Regulations an

  1. Static balance and function in children with cerebral palsy submitted to neuromuscular block and neuromuscular electrical stimulation: Study protocol for prospective, randomized, controlled trial

    Directory of Open Access Journals (Sweden)

    Kazon Soráia

    2012-05-01

    Full Text Available Abstract Background The use of botulinum toxin A (BT-A for the treatment of lower limb spasticity is common in children with cerebral palsy (CP. Following the administration of BT-A, physical therapy plays a fundamental role in potentiating the functionality of the child. The balance deficit found in children with CP is mainly caused by muscle imbalance (spastic agonist and weak antagonist. Neuromuscular electrical stimulation (NMES is a promising therapeutic modality for muscle strengthening in this population. The aim of the present study is to describe a protocol for a study aimed at analyzing the effects of NMES on dorsiflexors combined with physical therapy on static and functional balance in children with CP submitted to BT- A. Methods/Design Protocol for a prospective, randomized, controlled trial with a blinded evaluator. Eligible participants will be children with cerebral palsy (Levels I, II and III of the Gross Motor Function Classification System between five and 12 years of age, with independent gait with or without a gait-assistance device. All participants will receive BT-A in the lower limbs (triceps surae. The children will then be randomly allocated for either treatment with motor physical therapy combined with NMES on the tibialis anterior or motor physical therapy alone. The participants will be evaluated on three occasions: 1 one week prior to the administration of BT-A; 2 one week after the administration of BT-A; and 3 four months after the administration of BT-A (end of intervention. Spasticity will be assessed by the Modified Ashworth Scale and Modified Tardieu Scale. Static balance will be assessed using the Medicapteurs Fusyo pressure platform and functional balance will be assessed using the Berg Balance Scale. Discussion The aim of this protocol study is to describe the methodology of a randomized, controlled, clinical trial comparing the effect of motor physical therapy combined with NMES on the tibialis anterior

  2. Electric vehicles

    Science.gov (United States)

    1990-03-01

    Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. These concepts are discussed.

  3. Electric turbocompound control system

    Energy Technology Data Exchange (ETDEWEB)

    Algrain, Marcelo C. (Dunlap, IL)

    2007-02-13

    Turbocompound systems can be used to affect engine operation using the energy in exhaust gas that is driving the available turbocharger. A first electrical device acts as a generator in response to turbocharger rotation. A second electrical device acts as a motor to put mechanical power into the engine, typically at the crankshaft. Apparatus, systems, steps, and methods are described to control the generator and motor operations to control the amount of power being recovered. This can control engine operation closer to desirable parameters for given engine-related operating conditions compared to actual. The electrical devices can also operate in "reverse," going between motor and generator functions. This permits the electrical device associated with the crankshaft to drive the electrical device associated with the turbocharger as a motor, overcoming deficient engine operating conditions such as associated with turbocharger lag.

  4. Real time stagger of electric network advanced analysis functions of a modern control center; Escalonamento em tempo real das funcoes avancadas de analise de rede eletrica de um moderno centro de controle

    Energy Technology Data Exchange (ETDEWEB)

    Zagari, Eduardo Nicola Ferraz

    1996-02-01

    This work presents two models for implementation of staggers for network analysis functions in real time for a control center. The methodology is described. Tests were performed in a electric power system of Campinas region, Sao Paulo sate - Southeast Brazil. Results are presented.

  5. Closed-loop afferent electrical stimulation for recovery of hand function in individuals with motor incomplete spinal injury: early clinical results.

    Science.gov (United States)

    Schildt, Christopher J; Thomas, Sarah H; Powell, Elizabeth S; Sawaki, Lumy; Sunderam, Sridhar

    2016-08-01

    Afferent electrical stimulation is known to augment the effect of rehabilitative therapy through use-dependent cortical plasticity. Experiments pairing transcranial magnetic stimulation (TMS) with peripheral nerve stimulation (PNS) have shown a timing-dependent effect on motor evoked potential (MEP) amplitude suggesting that PNS applied in closed-loop (CL) mode could augment this effect through positive reinforcement. We present early results from a clinical trial in which an EEG brain-machine interface (BMI) was used to apply PNS to two subjects in response to motor intent detected from sensorimotor cortex in a cue-driven hand grip task. Both subjects had stable incomplete cervical spinal cord injury (SCI) with impaired upper limb function commensurate with the injury level. Twelve sessions of CL-PNS applied over a 4-6 week period yielded results suggesting improved hand grip strength and increased task-related modulation of the EEG in one hand of both subjects, and increased TMS-measured motor map area in one. These observations suggest that rehabilitation using such interactive therapies could benefit affected individuals.

  6. Inflammation-mediating cytokine response to acute handcycling exercise with/without functional electrical stimulation-evoked lower-limb cycling

    Directory of Open Access Journals (Sweden)

    Thomas A. W. Paulson, MSc

    2014-07-01

    Full Text Available This feasibility study compared the plasma inflammation-mediating cytokine response to an acute bout of handcycling (HC with and without the addition of functional electrical stimulation (FES-evoked lower-limb cycling. On two separate occasions, five recreationally active, community-based participants with motor complete paraplegia (thoracic 5–7 performed 30 min HC and hybrid exercise (HYB at a fixed power output. Venous blood samples were collected at rest, immediately postexercise, 1 h postexercise (post+1 and 2 h postexercise (post+2. Plasma interleukin (IL-6, IL-10, IL-1 receptor antagonist (IL-1ra, adrenaline, and cortisol concentrations were determined via enzyme-linked immunoassay. Plasma IL-6 concentrations were significantly (p 0.05 increase in IL-6 was observed at post+1 in HC, with concentrations significantly higher in HYB at post+2 (p < 0.02. Plasma IL-1ra was unaffected in both trials. Although not reaching statistical significance (p = 0.15, a ~1-fold increase in IL-10 concentration was seen in HYB at post+2. In contrast, increases in adrenaline (p < 0.04 and cortisol (p = 0.08 were observed immediately postexercise in HC and HYB. Initial findings suggest paralyzed skeletal muscle releases IL-6 in response to FES-evoked contractions. HYB may provide a greater anti-inflammatory potential in individuals with a thoracic spinal cord injury compared with HC alone.

  7. Evoked EMG versus Muscle Torque during Fatiguing Functional Electrical Stimulation-Evoked Muscle Contractions and Short-Term Recovery in Individuals with Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    Eduardo H. Estigoni

    2014-12-01

    Full Text Available This study investigated whether the relationship between muscle torque and m-waves remained constant after short recovery periods, between repeated intervals of isometric muscle contractions induced by functional electrical stimulation (FES. Eight subjects with spinal cord injury (SCI were recruited for the study. All subjects had their quadriceps muscles group stimulated during three sessions of isometric contractions separated by 5 min of recovery. The evoked-electromyographic (eEMG signals, as well as the produced torque, were synchronously acquired during the contractions and during short FES bursts applied during the recovery intervals. All analysed m-wave variables changed progressively throughout the three contractions, even though the same muscle torque was generated. The peak to peak amplitude (PtpA, and the m-wave area (Area were significantly increased, while the time between the stimulus artefact and the positive peak (PosT were substantially reduced when the muscles became fatigued. In addition, all m-wave variables recovered faster and to a greater extent than did torque after the recovery intervals. We concluded that rapid recovery intervals between FES-evoked exercise sessions can radically interfere in the use of m-waves as a proxy for torque estimation in individuals with SCI. This needs to be further investigated, in addition to seeking a better understanding of the mechanisms of muscle fatigue and recovery.

  8. Solvent primitive model of an electric double layer in slit-like pores: microscopic structure, adsorption and capacitance from a density functional approach

    Directory of Open Access Journals (Sweden)

    O. Pizio

    2014-06-01

    Full Text Available We investigate the electric double layer formed between charged walls of a slit-like pore and a solvent primitive model (SPM for electrolyte solution. The recently developed version of the weighted density functional approach for electrostatic interparticle interaction is applied to the study of the density profiles, adsorption and selectivity of adsorption of ions and solvent species. Our principal focus, however, is in the dependence of differential capacitance on the applied voltage, on the electrode and on the pore width. We discuss the properties of the model with respect to the behavior of a primitive model, i.e., in the absence of a hard-sphere solvent. We observed that the differential capacitance of the SPM on the applied electrostatic potential has the camel-like shape unless the ion fraction is high. Moreover, it is documented that the dependence of differential capacitance of the SPM on the pore width is oscillatory, which is in close similarity to the primitive model.

  9. The electric double layer at a rutile TiO₂ water interface modelled using density functional theory based molecular dynamics simulation.

    Science.gov (United States)

    Cheng, J; Sprik, M

    2014-06-18

    A fully atomistic model of a compact electric double layer at the rutile TiO2(1 1 0)-water interface is constructed by adding protons to bridging oxygens or removing them from H2O molecules adsorbed on terminal metal cation sites. The surface charge is compensated by F(-) or Na(+) counter ions in outer as well as inner sphere coordination. For each of the protonation states the energy of the TiO2 conduction band minimum is determined relative to the standard hydrogen electrode by computing the free energy for the combined insertion of an electron in the solid and a proton in solution away from the double layer using density functional theory based molecular dynamics methods. Interpreted as electrode potentials, this gives an estimate of the capacitance which is compared to the capacitance obtained from the difference in the average electrostatic potentials in the solid and aqueous phase. When aligned at the point of zero charge these two methods lead to almost identical potential-charge profiles. We find that inner sphere complexes have a slightly larger capacitance (0.4 F m(-2)) compared to outer sphere complexes (0.3 F m(-2)).

  10. Combined application of low-intensity pulsed ultrasound and functional electrical stimulation accelerates bone-tendon junction healing in a rabbit model.

    Science.gov (United States)

    Hu, Jianzhong; Qu, Jin; Xu, Daqi; Zhang, Tao; Qin, Ling; Lu, Hongbin

    2014-02-01

    The objective of this study was to elucidate the combined use of low-intensity pulsed ultrasound (LIPUS) and functional electrical stimulation (FES) on patella-patellar tendon (PPT) junction healing using a partial patellectomy model in rabbits. LIPUS was delivered continuously starting day 3 postoperative until week 6. FES was applied on quadriceps muscles to induce tensile force to the repaired PPT junction 5 days per week for 6 weeks since week 7 postoperatively. Forty rabbits with partial patellectomy were randomly divided into four groups: control, LIPUS alone, FES alone, and LIPUS + FES groups. At week 12, the PPT complexes were harvested for histology, radiographs, peripheral quantitative computed tomography, and biomechanical testing. There was better remodeling of newly formed bone and fibrocartilage zone in the three treatment groups compared with the control group. LIPUS and/or FES treatments significantly increased the area and bone mineral content of new bone. The failure load and ultimate strength of PPT complex were also highly improved in the three treatment groups. More new bone formed and higher tensile properties were showed in the LIPUS + FES group compared with the LIPUS or FES alone groups. Early LIPUS treatment and later FES treatment showed the additive effects of accelerating PPT junction healing.

  11. Synthesis and electrical characterization of low-temperature thermal-cured epoxy resin/functionalized silica hybrid-thin films for application as gate dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Na, Moonkyong, E-mail: nmk@keri.re.kr [HVDC Research Division, Korea Electrotechnology Research Institute, Changwon, 642-120 (Korea, Republic of); System on Chip Chemical Process Research Center, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 790-784 (Korea, Republic of); Kang, Young Taec [Creative and Fundamental Research Division, Korea Electrotechnology Research Institute, Changwon, 642-120 (Korea, Republic of); Department of Polymer Science and Engineering, Pusan National University, Busan, 609-735 (Korea, Republic of); Kim, Sang Cheol [HVDC Research Division, Korea Electrotechnology Research Institute, Changwon, 642-120 (Korea, Republic of); Kim, Eun Dong [Creative and Fundamental Research Division, Korea Electrotechnology Research Institute, Changwon, 642-120 (Korea, Republic of)

    2013-07-31

    Thermal-cured hybrid materials were synthesized from homogenous hybrid sols of epoxy resins and organoalkoxysilane-functionalized silica. The chemical structures of raw materials and obtained hybrid materials were characterized using Fourier transform infrared spectroscopy. The thermal resistance of the hybrids was enhanced by hybridization. The interaction between epoxy matrix and the silica particles, which caused hydrogen bonding and van der Waals force was strengthened by organoalkoxysilane. The degradation temperature of the hybrids was improved by approximately 30 °C over that of the parent epoxy material. The hybrid materials were formed into uniformly coated thin films of about 50 nm-thick using a spin coater. An optimum mixing ratio was used to form smooth-surfaced hybrid films. The electrical property of the hybrid film was characterized, and the leakage current was found to be well below 10{sup −6} A cm{sup −2}. - Highlights: • Preparation of thermal-curable hybrid materials using epoxy resin and silica. • The thermal stability was enhanced through hybridization. • The insulation property of hybrid film was investigated as gate dielectrics.

  12. Invited commentary on comparison of robotics, functional electrical stimulation, and motor learning methods for treatment of persistent upper extremity dysfunction after stroke: a randomized controlled trial.

    Science.gov (United States)

    Kwakkel, Gert; van Wegen, Erwin E; Meskers, Carel M

    2015-06-01

    In this issue of Archives of Physical Medicine and Rehabilitation, Jessica McCabe and colleagues report findings from their methodologically sound, dose-matched clinical trial in 39 patients beyond 6 months poststroke. In this phase II trial, the effects of 60 treatment sessions, each involving 3.5 hours of intensive practice plus either 1.5 hours of functional electrical stimulation (FES) or a shoulder-arm robotic therapy, were compared with 5 hours of intensive daily practice alone. Although no significant between-group differences were found on the primary outcome measure of Arm Motor Ability Test and the secondary outcome measure of Fugl-Meyer Arm motor score, 10% to 15% within-group therapeutic gains were on the Arm Motor Ability Test and Fugl-Meyer Arm. These gains are clinically meaningful for patients with stroke. However, the underlying mechanisms that drive these improvements remain poorly understood. The approximately $1000 cost reduction per patient calculated for the use of motor learning (ML) methods alone or combined with FES, compared with the combination of ML and shoulder-arm robotics, further emphasizes the need for cost considerations when making clinical decisions about selecting the most appropriate therapy for the upper paretic limb in patients with chronic stroke.

  13. Nanosecond pulse electric field activation of platelet-rich plasma reduces myocardial infarct size and improves left ventricular mechanical function in the rabbit heart.

    Science.gov (United States)

    Hargrave, Barbara; Li, Francis

    2012-12-01

    In the current study, we used the novel, nonchemical method of nanosecond pulsed electric fields (nsPEF) to investigate the efficiency of a protocol involving the in vivo treatment of the ischemic and reperfused heart and heart cells in culture with platelet-rich plasma (PRP). Associated with the restoration of blood flow to the ischemic tissue is a phenomenon referred to as "ischemic reperfusion injury." Clinically a type of reperfusion injury occurs during coronary bypass surgery once blood perfusion to the heart is restarted. Although the restoration of oxygen to ischemic myocardial cells is critical for tissue survival, reperfusion causes myocardial oxidative stress, attributable in part to the increased production of reactive oxygen species (ROS). Enhanced ROS production is associated with mitochondrial damage. Adult female New Zealand white rabbits were anesthetized and a left thoracotomy performed to expose the heart. The distal segment of the left anterior descending coronary artery was occluded for 15 minutes and then released so reperfusion of the tissue could occur. PRP (.21 mg/heart) or saline was injected into the ischemic area of the myocardium. Mechanical function of the left ventricle was analyzed using a Millar catheter attached to a Micro-Med Analysis System. H9c2 cells in culture were treated with 1 mL of nsPEF activated PRP (1.05 mg/flask) for 24 hours before analysis for ROS production or mitochondrial depolarization damage). The left ventricle contracted and relaxed faster and infarct size was reduced in hearts treated with PRP compared with saline. ROS production and mitochondrial depolarization were reduced in H9c2 cells treated with PRP and stimulated with hydrogen peroxide. These results provide evidence that nsPEFs can successfully be used to prepare PRP and that the PRP is functional in heart protection possibly by reducing ROS generation and stabilizing the mitochondria of the ischemic/reperfused heart.

  14. Hard x-ray photoemission and density functional theory study of the internal electric field in SrTiO3/LaAlO3 oxide heterostructures

    Science.gov (United States)

    Slooten, E.; Zhong, Zhicheng; Molegraaf, H. J. A.; Eerkes, P. D.; de Jong, S.; Massee, F.; van Heumen, E.; Kruize, M. K.; Wenderich, S.; Kleibeuker, J. E.; Gorgoi, M.; Hilgenkamp, H.; Brinkman, A.; Huijben, M.; Rijnders, G.; Blank, D. H. A.; Koster, G.; Kelly, P. J.; Golden, M. S.

    2013-02-01

    A combined experimental and theoretical investigation of the electronic structure of the archetypal oxide heterointerface system LaAlO3 on SrTiO3 is presented. High-resolution, hard x-ray photoemission is used to uncover the occupation of Ti 3d states and the relative energetic alignment—and hence internal electric fields—within the LaAlO3 layer. First, the Ti 2p core-level spectra clearly show occupation of Ti 3d states already for two unit cells of LaAlO3. Second, the LaAlO3 core levels were seen to shift to lower binding energy as the LaAlO3 overlayer thickness, n, was increased, agreeing with the expectations from the canonical electron transfer model for the emergence of conductivity at the interface. However, not only is the energy offset of only ˜300 meV between n=2 (insulating interface) and n=6 (metallic interface) an order of magnitude smaller than the simple expectation, but it is also clearly not the sum of a series of unit-cell-by-unit-cell shifts within the LaAlO3 block. Both of these facts argue against the simple charge-transfer picture involving a cumulative shift of the LaAlO3 valence bands above the SrTiO3 conduction bands, resulting in charge transfer only for n≥4. We discuss effects which could frustrate this elegant and simple charge-transfer model, concluding that although it cannot be ruled out, photodoping by the x-ray beam is unlikely to be the cause of the observed behavior. Turning to the theoretical data, our density functional simulations show that the presence of oxygen vacancies at the LaAlO3 surface at the 25% level reverses the direction of the internal field in the LaAlO3. Therefore, taking the experimental and theoretical results together, a consistent picture emerges for real-life samples in which nature does not wait until n=4 and already for n=2 mechanisms other than internal-electric-field-driven electron transfer from idealized LaAlO3 to near-interfacial states in the SrTiO3 substrate are active in heading off the

  15. Facile Exfoliation and Noncovalent Superacid Functionalization of Boron Nitride Nanosheets and Their Use for Highly Thermally Conductive and Electrically Insulating Polymer Nanocomposites.

    Science.gov (United States)

    Morishita, Takuya; Okamoto, Hirotaka

    2016-10-12

    There is an increasing demand for highly thermally conductive and electrically insulating polymer materials for next-generation electronic devices, power systems, and communication equipment. Boron nitride nanosheets (BNNSs) are insulating materials with extremely high thermal conductivity. However, BNNSs suffer from the lack of facile and low-cost methods for producing large volumes of BNNSs, and extremely low through-plane thermal conductivities of BNNS/polymer composites as compared to the in-plane thermal conductivities. Herein, highly soluble, noncovalently functionalized boron nitride nanosheets (NF-BNNSs) with chlorosulfonic acid (CSA) were prepared by extremely facile and low-cost direct exfoliation of hexagonal boron nitrides (h-BNs), and acted as excellent nanofillers for dramatically improving both in- and through-plane thermal conductivities of insulating polymers. CSA is a cheap and versatile superacid with a large production volume. CSA showed strong physical adsorption on h-BN surfaces, giving few-layered NF-BNNSs in high yields (up to ∼25%). The crystallinity of the NF-BNNS was perfectly maintained even after CSA treatment. The physical adsorption of CSAs imparted high solubility for BNNSs in various organic solvents, yielding NF-BNNS uniformly dispersed-thermoplastic polymer composite films through a simple wet-process using predispersed NF-BNNS solutions. Random dispersion of NF-BNNSs in thermoplastic polymer films dramatically enhanced both the in- and through-plane thermal conductivities (>10 W m(-1) K(-1)). The through-plane thermal conductivity of the NF-BNNS/polybutylene terephthalate (PBT) composite films was much greater (up to 11.0 W m(-1) K(-1)) than those previously reported for BNNS/thermoplastic polymer composites (≤2.6 W m(-1) K(-1)). These results are also due to an increase of interactions between the BNNS and polymer matrices, caused by physical adsorption of CSAs on BNNS surfaces. Moreover, the volume resistivity of the NF

  16. Atmospheric electricity

    CERN Document Server

    Chalmers, J Alan

    1957-01-01

    Atmospheric Electricity brings together numerous studies on various aspects of atmospheric electricity. This book is composed of 13 chapters that cover the main problems in the field, including the maintenance of the negative charge on the earth and the origin of the charges in thunderstorms. After a brief overview of the historical developments of atmospheric electricity, this book goes on dealing with the general principles, results, methods, and the MKS system of the field. The succeeding chapters are devoted to some aspects of electricity in the atmosphere, such as the occurrence and d

  17. Electrical stator

    Science.gov (United States)

    Fanning, Alan W.; Olich, Eugene E.

    1994-01-01

    An electrical stator of an electromagnetic pump includes first and second spaced apart coils each having input and output terminals for carrying electrical current. An elongate electrical connector extends between the first and second coils and has first and second opposite ends. The connector ends include respective slots receiving therein respective ones of the coil terminals to define respective first and second joints. Each of the joints includes a braze filler fixedly joining the connector ends to the respective coil terminals for carrying electrical current therethrough.

  18. 功能性电刺激对痉挛型双瘫型脑瘫患儿运动功能的影响%Effects of functional electrical stimulation on motor function in children with spastic diplegia

    Institute of Scientific and Technical Information of China (English)

    谢闽达; 许晶莉

    2013-01-01

    目的:探讨功能性电刺激对痉挛型双瘫型脑瘫患儿运动功能的影响。方法:选择痉挛型双瘫型脑瘫患儿共60例,将全部患儿随机分为治疗组与对照组,每组各30例,对照组采用常规综合康复治疗,治疗组在此基础上增加功能性电刺激治疗。刺激部位:胫骨前肌、股四头肌、臀大肌。2组患儿均持续治疗1个疗程,在康复治疗前及治疗后均进行粗大运动功能测试量表( gross motor function measure scale ,GMFM)检测徒手肌力法( manual muscle testing ,MMT)测试。结果:康复治疗后,治疗组肌力提高总有效率为83.33%。对照组肌力提高总有效率为66.67%,2组肌力比较有显著性差异(P<0.05);治疗后,2组GMFM总分均显著高于治疗前(P<0.01),治疗组GMFM总分显著高于对照组(P<0.05)。结论:功能性电刺激有助于改善脑瘫患儿的运动功能。%Objective: To investigate the effects of functional electrical stimulation ( FES) on motor function in children with spastic diplegia.Methods:60 children with spastic diplegia were randomly divided into treatment group ( n=30 ) and control group(n=30).All patients received combined therapy,while the treatment group was added with FES.The surface electrodes were applied on the anterior tibialis,quadriceps and gluteus maximus.The treatment was performed for 3 months and the meas-urements of gross motor function measure scale( GMFM) and manual muscle testing( MMT) were made before and after the reha-bilitation training for both groups.Results: The total effective rate of strength improvements in the treatment group was 83. 33%,which was 66.67% in the control group.There was significant difference between the two groups(P <0.05).It was found that the total of GMFM increased significantly after 3 months in both groups(P<0.01) and it was significantly higher in the treatment group than in the control group ( P<0 .05

  19. The Newnes guide to home electrics

    CERN Document Server

    Burdett, Geoffrey

    2013-01-01

    Home Electrics, Second Edition provides a do-it-yourself (DIY) guide to residential electric systems. The book is comprised of 15 chapters that cover the different aspects of home electrics. The topics covered in the text include electrical installation, rewiring, power circuits, electrical hardware, electrical repairs, tools, and safety. The book also discusses a specific area or function of home electronics, such as lighting system, lamps, electric cookers, and outdoor electrical extension. The book will be of great use to individuals interested in learning how to conduct proper home electri

  20. Bipedal gait experiment for functional electrical stimulation%服务于功能性电刺激的双足步态实验

    Institute of Scientific and Technical Information of China (English)

    王颖; 张定国

    2012-01-01

    BACKGROUND: Functional electrical stimulation (FES) uses electrical pulse of low level to stimulate the peripheral nerve of muscles in order to restore the motor functions, and it has already achieved clinical success in area of paraplegic walking. However, the patterns of FES are inflexible, unstable and hard to operate for the end-users at present.OBJECTIVE: To study the synergistic action of the muscles involved in walking movements for simplifying the design of FES control patterns based on gait analysis and to make the subjects perform expected involuntary walking movements using FES.METHODS: According to the characteristics of bipedal walking, a method of gait research was proposed based on measurement and analysis of joint angle and electromyography signal. It served for FES system design, which generated the desired stimulation patterns for muscle groups of lower limbs, and realized the corresponding collaborative activation of the muscle groups.RESULTS AND CONCLUSION: Satisfactory involuntary walking of a healthy subject without self-control was realized using the FES method proposed. The results from the experiment had verified the feasibility of FES in lower limb rehabilitation. It sheds light on more complex FES control methods, and provides experimental support for clinical study on paralyzed patients in future.%背景:功能性电刺激利用低频弱电流脉冲刺激失去神经控制的肌肉已经在截瘫行走的临床应用中取得了小范围成功,但现有的电刺激模式存在不灵活、不易操作、且稳定性不高的缺点.目的:基于步态分析方法,研究涉及到步行动作的各肌肉群的协同动作关系,将肌肉电刺激模式简化为无需患者操作的规律性控制策略,并验证该策略在功能性电刺激实验中的有效性.方法:针对双足步行的特点,提出一种基于关节角变化趋势及肌电信号强度变化的步态研究方法,旨在服务于功能性电刺激的设计,为下肢肌肉

  1. Electric machine

    Science.gov (United States)

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  2. Investigation on the Evolution of Structural, Electrical and Transmitting Properties of Aluminium Doped Zinc Oxide Thin Film as a function of substrate temperature

    Science.gov (United States)

    Devasia, Sebin; Athma, P. V.; Jose, Anumol; Anila, E. I.

    2016-09-01

    Improved electrical conductivity of aluminium doped zinc oxide (AZO) thin films deposited by chemical spray pyrolysis method at various substrate temperatures is reported. Detailed investigation on the structural, electrical and optical properties were carried out using XRD, four point probe and UV-Vis-NIR measurements. The films deposited at 450 °C shows better conductivity and transparency as compared to the films grown at lower temperatures. Electrical conductivity, determined using four point probe measurements, is 6.271 × 102 μcm with an average transmittance of 70 % in the visible and IR region.

  3. Home-Based Functional Electrical Stimulation for Long-Term Denervated Human Muscle: History, Basics, Results and Perspectives of the Vienna Rehabilitation Strategy

    Science.gov (United States)

    Kern, Helmut

    2014-01-01

    We will here discuss the following points related to Home-based Functional Electrical Stimulation (h-b FES) as treatment for patients with permanently denervated muscles in their legs: 1. Upper (UMN) and lower motor neuron (LMN) damage to the lower spinal cord; 2. Muscle atrophy/hypertrophy versus processes of degeneration, regeneration, and recovery; 3. Recovery of twitch- and tetanic-contractility by h-b FES; 4. Clinical effects of h-b FES using the protocol of the “Vienna School”; 5. Limitations and perspectives. Arguments in favor of using the Vienna protocol include: 1. Increased muscle size in both legs; 2. Improved tetanic force production after 3-5 months of percutaneous stimulation using long stimulus pulses (> 100 msec) of high amplitude (> 80 mAmp), tolerated only in patients with no pain sensibility; 3. Histological and electron microscopic evidence that two years of h-b FES return muscle fibers to a state typical of two weeks denervated muscles with respect to atrophy, disrupted myofibrillar structure, and disorganized Excitation-Contraction Coupling (E-CC) structures; 4. The excitability never recovers to that typical of normal or reinnervated muscles where pulses less than 1 msec in duration and 25 mAmp in intensity excite axons and thereby muscle fibres. It is important to motivate these patients for chronic stimulation throughout life, preferably standing up against the load of the body weight rather than sitting. Only younger and low weight patients can expect to be able to stand-up and do some steps more or less independently. Some patients like to maintain the h-b FES training for decades. Limitations of the procedure are obvious, in part related to the use of multiple, large surface electrodes and the amount of time patients are willing to use for such muscle training. PMID:26913127

  4. European transition to a low carbon electricity system using a mix of variable renewable energies: carbon saving trajectories as functions of production and storage capacity.

    Science.gov (United States)

    Francois, Baptiste; Creutin, Jean-Dominique

    2016-04-01

    Today, most of the produced energy is generated from fossil energy sources (i.e. coal, petroleum). As a result, the energy sector is still the main source of greenhouse gas in the atmosphere. For limiting greenhouse gas emission, a transition from fossil to renewable energy is required, increasing gradually the fraction energy coming from variable renewable energy (i.e. solar power, wind power and run-of-the river hydropower, hereafter denoted as VRE). VRE penetration, i.e. the percentage of demand satisfied by variable renewables assuming no storage capacity, is hampered by their variable and un-controllable features. Many studies show that combining different VRE over space smoothes their variability and increases their global penetration by a better match of demand fluctuations. When the demand is not fully supplied by the VRE generation, backup generation is required from stored energy (mostly from dams) or fossil sources, the latter being associated with high greenhouse gas emission. Thus the VRE penetration is a direct indicator of carbon savings and basically depends on the VRE installed capacity, its mix features, and on the installed storage capacity. In this study we analyze the European transition to a low carbon electricity system. Over a selection of representative regions we analyze carbon saving trajectories as functions of VRE production and storage capacities for different scenarios mixing one to three VRE with non-renewables. We show substantial differences between trajectories when the mix of sources is far from the local optimums, when the storage capacity evolves. We bring new elements of reflection about the effect of transport grid features from local independent systems to a European "copper plate". This work is part of the FP7 project COMPLEX (Knowledge based climate mitigation systems for a low carbon economy; Project FP7-ENV-2012 number: 308601; http://www.complex.ac.uk/).

  5. Effect of the 5-HT(1A) partial agonist buspirone on regional brain electrical activity in man: a functional neuroimaging study using low-resolution electromagnetic tomography (LORETA).

    Science.gov (United States)

    Anderer, P; Saletu, B; Pascual-Marqui, R D

    2000-12-04

    In a double-blind, placebo-controlled study, the effects of 20 mg buspirone - a 5-HT(1A) partial agonist - on regional electrical generators within the human brain were investigated utilizing three-dimensional EEG tomography. Nineteen-channel vigilance-controlled EEG recordings were carried out in 20 healthy subjects before and 1, 2, 4, 6 and 8 h after drug intake. Low-resolution electromagnetic tomography (LORETA; Key Institute for Brain-Mind Research, software: http://www.keyinst.unizh.ch) was computed from spectrally analyzed EEG data, and differences between drug- and placebo-induced changes were displayed as statistical parametric maps. Data were registered to the Talairach-Tournoux human brain atlas available as a digitized MRI (McConnell Brain Imaging Centre: http://www.bic.mni.mcgill.ca). At the pharmacodynamic peak (1st hour), buspirone increased theta and decreased fast alpha and beta sources. Areas of theta increase were mainly the left temporo-occipito-parietal and left prefrontal cortices, which is consistent with PET studies on buspirone-induced decreases in regional cerebral blood flow and fenfluramine-induced serotonin activation demonstrated by changes in regional cerebral glucose metabolism. In later hours (8th hour) with lower buspirone plasma levels, delta, theta, slow alpha and fast beta decreased, predominantly in the prefrontal and anterior limbic lobe. Whereas the results of the 1st hour speak for a slight CNS sedation (more in the sense of relaxation), those obtained in the 8th hour indicate activation. Thus, LORETA may provide useful and direct information on drug-induced changes in central nervous system function in man.

  6. Home-based Functional Electrical Stimulation for long-term denervated human muscle: History, basics, results and perspectives of the Vienna Rehabilitation Strategy

    Directory of Open Access Journals (Sweden)

    Helmut Kern

    2014-03-01

    Full Text Available We will here discuss the following points related to Home-based Functional Electrical Stimulation (h-b FES as treatment for patients with permanently denervated muscles in their legs: 1. Upper (UMN and lower motor neuron (LMN damage to the lower spinal cord; 2. Muscle atrophy/hypertrophy versus processes of degeneration, regeneration, and recovery; 3. Recovery of twitch- and tetanic-contractility by h-b FES; 4. Clinical effects of h-b FES using the protocol of the “Vienna School”; 5. Limitations and perspectives. Arguments in favor of using the Vienna protocol include: 1. Increased muscle size in both legs; 2. Improved tetanic force production after 3-5 months of percutaneous stimulation using long stimulus pulses (> 100 msec of high amplitude (> 80 mAmp, tolerated only in patients with no pain sensibility; 3. Histological and electron microscopic evidence that two years of h-b FES return muscle fibers to a state typical of two weeks denervated muscles with respect to atrophy, disrupted myofibrillar structure, and disorganized Excitation-Contraction Coupling (E-CC structures; 4. The excitability never recovers to that typical of normal or reinnervated muscles where pulses less than 1 msec in duration and 25 mAmp in intensity excite axons and thereby muscle fibres. It is important to motivate these patients for chronic stimulation throughout life, preferably standing up against the load of the body weight rather than sitting. Only younger and low weight patients can expect to be able to stand-up and do some steps more or less independently. Some patients like to maintain the h-b FES training for decades. Limitations of the procedure are obvious, in part related to the use of multiple, large surface electrodes and the amount of time patients are willing to use for such muscle training.

  7. Use of anisotropic modelling in electrical impedance tomography: description of method and preliminary assessment of utility in imaging brain function in the adult human head.

    Science.gov (United States)

    Abascal, Juan-Felipe P J; Arridge, Simon R; Atkinson, David; Horesh, Raya; Fabrizi, Lorenzo; De Lucia, Marzia; Horesh, Lior; Bayford, Richard H; Holder, David S

    2008-11-01

    Electrical Impedance Tomography (EIT) is an imaging method which enables a volume conductivity map of a subject to be produced from multiple impedance measurements. It has the potential to become a portable non-invasive imaging technique of particular use in imaging brain function. Accurate numerical forward models may be used to improve image reconstruction but, until now, have employed an assumption of isotropic tissue conductivity. This may be expected to introduce inaccuracy, as body tissues, especially those such as white matter and the skull in head imaging, are highly anisotropic. The purpose of this study was, for the first time, to develop a method for incorporating anisotropy in a forward numerical model for EIT of the head and assess the resulting improvement in image quality in the case of linear reconstruction of one example of the human head. A realistic Finite Element Model (FEM) of an adult human head with segments for the scalp, skull, CSF, and brain was produced from a structural MRI. Anisotropy of the brain was estimated from a diffusion tensor-MRI of the same subject and anisotropy of the skull was approximated from the structural information. A method for incorporation of anisotropy in the forward model and its use in image reconstruction was produced. The improvement in reconstructed image quality was assessed in computer simulation by producing forward data, and then linear reconstruction using a sensitivity matrix approach. The mean boundary data difference between anisotropic and isotropic forward models for a reference conductivity was 50%. Use of the correct anisotropic FEM in image reconstruction, as opposed to an isotropic one, corrected an error of 24 mm in imaging a 10% conductivity decrease located in the hippocampus, improved localisation for conductivity changes deep in the brain and due to epilepsy by 4-17 mm, and, overall, led to a substantial improvement on image quality. This suggests that incorporation of anisotropy in

  8. Effects of brain-derived neurotrophic factor (BDNF) and electrical stimulation on survival and function of cochlear spiral ganglion neurons in deafened, developing cats.

    Science.gov (United States)

    Leake, Patricia A; Stakhovskaya, Olga; Hetherington, Alexander; Rebscher, Stephen J; Bonham, Ben

    2013-04-01

    Both neurotrophic support and neural activity are required for normal postnatal development and survival of cochlear spiral ganglion (SG) neurons. Previous studies in neonatally deafened cats demonstrated that electrical stimulation (ES) from a cochlear implant can promote improved SG survival but does not completely prevent progressive neural degeneration. Neurotrophic agents combined with an implant may further improve neural survival. Short-term studies in rodents have shown that brain-derived neurotrophic factor (BDNF) promotes SG survival after deafness and may be additive to trophic effects of stimulation. Our recent study in neonatally deafened cats provided the first evidence of BDNF neurotrophic effects in the developing auditory system over a prolonged duration Leake et al. (J Comp Neurol 519:1526-1545, 2011). Ten weeks of intracochlear BDNF infusion starting at 4 weeks of age elicited significant improvement in SG survival and larger soma size compared to contralateral. In the present study, the same deafening and BDNF infusion procedures were combined with several months of ES from an implant. After combined BDNF + ES, a highly significant increase in SG numerical density (>50 % improvement re: contralateral) was observed, which was significantly greater than the neurotrophic effect seen with ES-only over comparable durations. Combined BDNF + ES also resulted in a higher density of myelinated radial nerve fibers within the osseous spiral lamina. However, substantial ectopic and disorganized sprouting of these fibers into the scala tympani also occurred, which may be deleterious to implant function. EABR thresholds improved (re: initial thresholds at time of implantation) on the chronically stimulated channels of the implant. Terminal electrophysiological studies recording in the inferior colliculus (IC) revealed that the basic cochleotopic organization was intact in the midbrain in all studied groups. In deafened controls or after ES-only, lower IC

  9. 电刺激对脑梗死大鼠运动功能和Rho激酶表达的影响%Effects of electric stimulation on motor function and the expression of Rho kinase following cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    陈涛; 张秀清; 唐吉友

    2010-01-01

    目的 探讨单侧与双侧电刺激对脑梗死大鼠肢体运动功能和Rho激酶表达的影响.方法 采用线栓法制作Sprague-Dawley大鼠大脑中动脉永久性闭塞模型,将造模成功且存活的脑梗死大鼠分为假手术组、对照组、单侧电刺激组、双侧电刺激组(各36只),假手术组、对照组自然恢复,单、双侧电刺激组接受电刺激治疗.利用平衡木试验(BWT)观察造模后第3天、第7天、第14天和第21天各组大鼠运动功能恢复情况,同时采用免疫组化染色法检测脑梗死灶周边区Rho激酶的表达水平,采用2,3,5-氯化三苯基四氮唑(TTC)染色法检测脑梗死灶体积的变化.结果 第7,14,21天,电刺激组大鼠BWT评分明显高于对照组(P0.05),第21天脑梗死灶体积显著缩小(P0.05).结论 早期电刺激能够促进脑梗死大鼠运动功能的恢复,并且促进脑梗死灶体积缩小,双侧电刺激疗效优于单侧电刺激,其机制可能与下调脑梗死灶周边区Rho激酶的表达有关.%Objective To investigate the effects of electric stimulation on motor function and expression of Rho kinase following cerebral infarction in rats. Methods Acute cerebral infarction was modeled in adult male Sprague-Dawley ( SD) rats using the permanent middle cerebral artery occlusion ( PMCAO) technique. The rats were randomly divided into sham operation, control, unilateral electric stimulation and bilateral electric stimulation groups ( each group had 36 rats). Electric stimulation was applied to the paralyzed ( unilateral or bilateral) limbs in the last two groups. Motor function recovery and the expression of Rho kinase were examined using a beam walking test ( BWT) and immunohistochemistry respectively at the 3rd, 7th, 14th and 21st day after stimulation. In addition, the cerebral infarction volume was also determined by 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining at different time points. Results Motor function improved significantly in the

  10. Functional electrical stimulation as a safe and effective treatment for equine epaxial muscle spasms: Clinical evaluations and histochemical morphometry of mitochondria in muscle biopsies

    Directory of Open Access Journals (Sweden)

    Barbara Ravara

    2015-03-01

    Full Text Available Functional Electrical Stimulation (FES has been used extensively over several decades to reverse muscle atrophy during rehabilitation for spinal cord injury patients. The benefits of the technology are being expanded into other areas, and FES has been recently utilized for injury rehabilitation and performance enhancement in horses. Six retired horses (age from 10 to 17 yrs that had been previously used mainly for dressage riding were selected for this study. Clinical evaluation found epaxial muscle spasms in all horses with minimal to no pelvic extension when manually palpated. FES treatments were performed on the sacral/lumbar region 3 times per week for a period of 8 weeks, obtaining a total of 22 treatments per horse. The Modified Ashworth Scale for grading muscle spasms found a one grade improvement after approximately four FES treatments, indicating improved functional movement of the sacral/lumbar region, supporting the evidence by clinical palpations that a reduction in epaxial muscle spasms occurred. Skeletal muscle biopsies Pre and Post FES treatments were obtained from the longissimus lumborum muscle. Cryosections were stained with a Hemotoxylin-Eosin (H-E, and nicotinamide adenine dinucleotide tetrazolium reductase reaction (NADH-TR. The eventual size change of the muscle fibers were evaluated by morphometry in the H-E and NADH-TR stained cryosections, while in the NADH-TR slides the histochemical density and distribution of mitochondria were also determined. The main results of the morphometric analyses were: 1 As expected for the type of FES treatment used in this study, only a couple of horses showed significant increases in mean muscle fiber size when Pre- vs Post-FES biopsies were compared; 2 In the older horses, there were sparse (or many in one horse very atrophic and angulated muscle fibers in both Pre- and Post-FES samples, whose attributes and distribution suggests that they were denervated due to a distal neuropathy; 3 The

  11. Neuromuscular electrical stimulation and dietary interventions to reduce oxidative stress in a secondary progressive multiple sclerosis patient leads to marked gains in function: a case report

    OpenAIRE

    2009-01-01

    Neuromuscular electrical stimulation has been used to aid musculoskeletal recovery. Excessive oxidative stress and excitoxicity are implicated in secondary progressive multiple sclerosis. A 52-year-old white female with SPMS had been scooter- and cane-dependent for 4 years. She requested and received a trial of neuromuscular electrical stimulation. Two months after initiating NMES the patient adopted several nutritional interventions to lower oxidative stress and excito-toxicity. During the f...

  12. Electric fields and electrical insulation

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson

    2002-01-01

    The adoption of a field-theoretical approach to problems arising in the framework of electrical insulation is discussed with reference to six main topics, which have been addressed over the last 30 years. These include uniform field electrodes, Green's differential equation, electrode surface......, it is amply demonstrated that such an approach can lead to significant progress in many areas of electrical insulation....

  13. Electrical Conductivity.

    Science.gov (United States)

    Hershey, David R.; Sand, Susan

    1993-01-01

    Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)

  14. Electricity derivatives

    CERN Document Server

    Aïd, René

    2015-01-01

    Offering a concise but complete survey of the common features of the microstructure of electricity markets, this book describes the state of the art in the different proposed electricity price models for pricing derivatives and in the numerical methods used to price and hedge the most prominent derivatives in electricity markets, namely power plants and swings. The mathematical content of the book has intentionally been made light in order to concentrate on the main subject matter, avoiding fastidious computations. Wherever possible, the models are illustrated by diagrams. The book should allow prospective researchers in the field of electricity derivatives to focus on the actual difficulties associated with the subject. It should also offer a brief but exhaustive overview of the latest techniques used by financial engineers in energy utilities and energy trading desks.

  15. Distinctive Steady-State Heart Rate and Blood Pressure Responses to Passive Robotic Leg Exercise and Functional Electrical Stimulation During Head-up Tilt

    Directory of Open Access Journals (Sweden)

    Amirehsan Sarabadani Tafreshi

    2016-12-01

    Full Text Available Tilt tables enable early mobilization of patients by providing verticalization. But there is a high risk of orthostatic hypotension provoked by verticalization, especially after neurological diseases such as spinal cord injury. Robot-assisted tilt tables might be an alternative as they add passive robotic leg exercise (PE that can be enhanced with functional electrical stimulation (FES to the verticalization, thus reducing the risk of orthostatic hypotension. We hypothesized that the influence of PE on the cardiovascular system during verticalization depends on the verticalization angle, and FES strengthens the PE influence. To test our hypotheses, we investigated the PE effects on the cardiovascular parameters heart rate (HR, and systolic and diastolic blood pressures (sBP, dBP at different angles of verticalization in a healthy population. Ten healthy subjects on a robot-assisted tilt table underwent four different study protocols while HR, sBP and dBP were measured: (1 head-up tilt to 60° and 71° without PE; (2 PE at 20°, 40°, and 60° of head-up tilt; (3 PE while constant FES intensity was applied to the leg muscles, at 20°, 40°, and 60° of head-up tilt; (4 PE with variation of the applied FES intensity at 0°, 20°, 40°, and 60° of head-up tilt. Linear mixed models were used to model changes in HR, sBP, and dBP responses. The models show that: (1 head-up tilt alone resulted in statistically significant increases in HR and dBP, but no change in sBP. (2 PE during head-up tilt resulted in statistically significant changes in HR, sBP, and dBP, but not at each angle and not always in the same direction (i.e., increase or decrease of cardiovascular parameters. Neither adding (3 FES at constant intensity to PE nor (4 variation of FES intensity during PE had any statistically significant effects on the cardiovascular parameters.The effect of PE on the cardiovascular system during head-up tilt is strongly dependent on the verticalization

  16. Effectiveness of bisphosphonate analogues and functional electrical stimulation on attenuating post-injury osteoporosis in spinal cord injury patients- a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Ke-Vin Chang

    Full Text Available BACKGROUND: Various pharmacologic and non-pharmacologic approaches have been applied to reduce sublesional bone loss after spinal cord injury (SCI, and the results are inconsistent across the studies. The objective of this meta-analysis was to investigate whether the two most-studied interventions, bisphosphonate analogues and functional electrical stimulation (FES, could effectively decrease bone mineral density (BMD attenuation and/or restore lost BMD in the SCI population. METHODS: Randomized controlled trials, quasi-experimental studies, and prospective follow-up studies employing bisphosphonates or FES to treat post-SCI osteoporosis were identified in PubMed and Scopus. The primary outcome was the percentage of BMD change from baseline measured by dual-energy X-ray absorptiometry (DEXA or computed tomography (CT. Data were extracted from four points: the 3rd, 6th, 12th, and 18th month after intervention. RESULTS: A total of 19 studies were included in the analysis and involved 364 patients and 14 healthy individuals. Acute SCI participants treated with bisphosphonate therapy demonstrated a trend toward less bone loss than participants who received placebos or usual care. A significant difference in BMD decline was noted between both groups at the 3rd and 12th month post-medication. The subgroup analysis failed to show the superiority of intravenous bisphosphonate over oral administration. Regarding FES training, chronic SCI patients had 5.96% (95% CI, 2.08% to 9.84%, 7.21% (95%CI, 1.79% to 12.62%, and 9.56% (95% CI, 2.86% to 16.26% increases in BMD at the 3rd, 6th, and 12th months post-treatment, respectively. The studies employing FES ≥ 5 days per week were likely to have better effectiveness than studies using FES ≤ 3 days per week. CONCLUSIONS: Our meta-analysis indicated bisphosphonate administration early following SCI effectively attenuated sublesional bone loss. FES intervention for chronic SCI patients could significantly

  17. Electric behavior of functional glasses based on TeO{sub 2}; Comportamiento electrico de vidrios funcionales con base en TeO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Terny, S.; Rubia, M. a. de la; Barolin, S.; Alonso, R. E.; Frutos, J. de; Frechero, M. A.

    2014-02-01

    In this paper we study the structural and electrical behavior of glass-ceramic material of general formula: xMgO (1-x) (0.5V{sub 2}O{sub 5}.0.5MoO{sub 3})2TeO{sub 2} (0{<=} x{<=}0.9) through measurements of density, molar volume, oxygen packing density (OPD), differential scanning calorimetry (DSC) and Raman spectroscopy: electric behavior was studied by impedance spectroscopy. We found that magnesium cation induces the growth of slightly crystallized areas inside the material. Those nanocrystallizations were detected to a greater extent by atomic force microscopy (AFM) and in lesser extent by X-ray diffraction (XRD). Regarding the electrical measurements, it can be established that magnesium cation does not act as good ionic conductor in this material. (Author)

  18. Habitual functional electrical stimulation therapy improves gait kinematics and walking performance, but not patient-reported functional outcomes, of people with multiple sclerosis who present with foot-drop.

    Directory of Open Access Journals (Sweden)

    Marietta L van der Linden

    Full Text Available BACKGROUND: People with Multiple Sclerosis (pwMS often experience a disturbed gait function such as foot-drop. The objective of this pilot study was to investigate the medium term effects of using Functional Electrical Stimulation (FES to treat foot-drop over a period 12 weeks on gait and patient reported outcomes of pwMS. METHODS AND FINDINGS: Nine pwMS aged 35 to 64 (2 males, 7 females were assessed on four occasions; four weeks before baseline, at baseline and after six weeks and twelve weeks of FES use. Joint kinematics and performance on the 10 meter and 2 minute walk tests (10WT, 2 minWT were assessed with and without FES. Participants also completed the MS walking Scale (MSWS, MS impact scale (MSIS29, Fatigue Severity Score (FSS and wore an activity monitor for seven days after each assessment. Compared to unassisted walking, FES resulted in statistically significant improvements in peak dorsiflexion in swing (p = 0.006, 10MWT (p = 0.006 and 2 minWT (p = 0.002. Effect sizes for the training effect, defined as the change from unassisted walking at baseline to that at 12 weeks, indicated improved ankle angle at initial contact (2.6°, 95% CI -1° to 4°, d = 0.78, and a decrease in perceived exertion over the 2 min walking tests (-1.2 points, 95% CI -5.7 to 3.4, d = -0.86. Five participants exceeded the Minimally Detectable Change (MDC for a training effect on the 10mWT, but only two did so for the 2 minWT. No effects of the use of FES for 12 weeks were found for MSWS, MSIS29, FSS or step count. CONCLUSION: Although FES to treat foot-drop appears to offer the potential for a medium term training effect on ankle kinematics and walking speed, this was not reflected in the patient reported outcomes. This observed lack of relationship between objective walking performance and patient reported outcomes warrants further investigation. TRIAL REGISTRATION: ClinicalTrials.gov NCT01977287.

  19. Functional

    Directory of Open Access Journals (Sweden)

    Fedoua Gandia

    2014-07-01

    Full Text Available The study was carried out to investigate the effects of inhaled Mg alone and associated with F in the treatment of bronchial hyperresponsiveness. 43 male Wistar rats were randomly divided into four groups and exposed to inhaled NaCl 0.9%, MeCh, MgSO4 and MgF2. Pulmonary changes were assessed by means of functional tests and quantitative histological examination of lungs and trachea. Results revealed that delivery of inhaled Mg associated with F led to a significant decrease of total lung resistance better than inhaled Mg alone (p < 0.05. Histological examinations illustrated that inhaled Mg associated with F markedly suppressed muscular hypertrophy (p = 0.034 and bronchoconstriction (p = 0.006 in MeCh treated rats better than inhaled Mg alone. No histological changes were found in the trachea. This study showed that inhaled Mg associated with F attenuated the main principle of the central components of changes in MeCh provoked experimental asthma better than inhaled Mg alone, potentially providing a new therapeutic approach against asthma.

  20. Towards the hybrid organic semiconductor fet (hosfet) : electrical and electrochemical characterization of functionalized and unfunctionalized, covalently bound organic monolayers on silicon surfaces

    NARCIS (Netherlands)

    Faber, Erik Jouwert

    2006-01-01

    Since their introduction in 1993 the class of covalently bound organic monolayers on oxide free silicon surfaces have found their way to multiple application fields such as passivation layers in solar cells, masking layers in lithographic processing, insulating films in hybrid moleculesilicon electr

  1. Bond length and electric current oscillation of long linear carbon chains: Density functional theory, MpB model, and quantum spin transport studies

    Energy Technology Data Exchange (ETDEWEB)

    Oeiras, R. Y.; Silva, E. Z. da [Institute of Physics “Gleb Wataghin”, University of Campinas-Unicamp, 13083-859 Campinas, SP (Brazil)

    2014-04-07

    Carbon linear atomic chains attached to graphene have experimentally been produced. Motivated by these results, we study the nature of the carbon bonds in these nanowires and how it affects their electrical properties. In the present study we investigate chains with different numbers of atoms and we observe that nanowires with odd number of atoms present a distinct behavior than the ones with even numbers. Using graphene nanoribbons as leads, we identify differences in the quantum transport of the chains with the consequence that even and odd numbered chains have low and high electrical conduction, respectively. We also noted a dependence of current with the wire size. We study this unexpected behavior using a combination of first principles calculations and simple models based on chemical bond theory. From our studies, the electrons of carbon nanowires present a quasi-free electron behavior and this explains qualitatively the high electrical conduction and the bond lengths with unexpected values for the case of odd nanowires. Our study also allows the understanding of the electric conduction dependence with the number of atoms and their parity in the chain. In the case of odd number chains a proposed π-bond (MpB) model describes unsaturated carbons that introduce a mobile π-bond that changes dramatically the structure and transport properties of these wires. Our results indicate that the nature of bonds plays the main role in the oscillation of quantum electrical conduction for chains with even and odd number of atoms and also that nanowires bonded to graphene nanoribbons behave as a quasi-free electron system, suggesting that this behavior is general and it could also remain if the chains are bonded to other materials.

  2. Bond length and electric current oscillation of long linear carbon chains: Density functional theory, MpB model, and quantum spin transport studies

    Science.gov (United States)

    Oeiras, R. Y.; da Silva, E. Z.

    2014-04-01

    Carbon linear atomic chains attached to graphene have experimentally been produced. Motivated by these results, we study the nature of the carbon bonds in these nanowires and how it affects their electrical properties. In the present study we investigate chains with different numbers of atoms and we observe that nanowires with odd number of atoms present a distinct behavior than the ones with even numbers. Using graphene nanoribbons as leads, we identify differences in the quantum transport of the chains with the consequence that even and odd numbered chains have low and high electrical conduction, respectively. We also noted a dependence of current with the wire size. We study this unexpected behavior using a combination of first principles calculations and simple models based on chemical bond theory. From our studies, the electrons of carbon nanowires present a quasi-free electron behavior and this explains qualitatively the high electrical conduction and the bond lengths with unexpected values for the case of odd nanowires. Our study also allows the understanding of the electric conduction dependence with the number of atoms and their parity in the chain. In the case of odd number chains a proposed π-bond (MpB) model describes unsaturated carbons that introduce a mobile π-bond that changes dramatically the structure and transport properties of these wires. Our results indicate that the nature of bonds plays the main role in the oscillation of quantum electrical conduction for chains with even and odd number of atoms and also that nanowires bonded to graphene nanoribbons behave as a quasi-free electron system, suggesting that this behavior is general and it could also remain if the chains are bonded to other materials.

  3. electric vehicle

    Directory of Open Access Journals (Sweden)

    W. R. Lee

    1999-01-01

    Full Text Available A major problem facing battery-powered electric vehicles is in their batteries: weight and charge capacity. Thus, a battery-powered electric vehicle only has a short driving range. To travel for a longer distance, the batteries are required to be recharged frequently. In this paper, we construct a model for a battery-powered electric vehicle, in which driving strategy is to be obtained such that the total travelling time between two locations is minimized. The problem is formulated as an optimization problem with switching times and speed as decision variables. This is an unconventional optimization problem. However, by using the control parametrization enhancing technique (CPET, it is shown that this unconventional optimization is equivalent to a conventional optimal parameter selection problem. Numerical examples are solved using the proposed method.

  4. 不同微场分布函数对Stark加宽和频移的影响%The Stark Broadening and Stark Shift with Different Electric Microfield Distribution Functions

    Institute of Scientific and Technical Information of China (English)

    冉俊霞; 李霞; 张少朋; 董丽芳

    2009-01-01

    The Stark broadening and Stark shift were described with different electric microfield distribution functions. These microfield distribution functions include Holtsmark, Neutral Point, Nearest-Neighbor and Mayer model microfield distribution function. The Stark profiles with four microfield distribution functions were studied and the Stark broadening and Stark shift were obtained from the Stark profiles to study the influence of different electric microfield distribution functions on Stark broade-ning and Stark shift. The results show that the influence of different electric microfield distribution functions on Stark broadening and Stark shift increases with the plasma ions impact parameter with the same electrons impact broadening parameter. With the increase in the plasma electrons impact parameter the influence of different electric microfield distribution functions increases with the same ion impact broadening parameter. Especially, the influence of Mayer model electric microfield distribution function is very distinct when the ion impact broadening parameter is larger. It is illuminated that the plasma ions intense impact has great influence on the spectral line profile. It is very important for the plasma diagnosis to select appropriate electric microfield distri-bution function. The results have important reference for the plasma diagnosis.%分别采用Holtsmark,Neutral Point,Nearest-Neighbor和Mayer模犁微场分布函数对Stark线型进行了研究,进而得到相应微场函数下的Stark加宽和频移,研究了4种不同的微场分布函数对Stark加宽和频移的影响.研究结果表明,在电子加宽参数不变时,4种微场分布函数对stark加宽和频移的影响随离子加宽参数的增加而增加;在离子加宽参数不变时,4种微场分布甬数对Stark加宽和频移的影响随电子加宽参数的增加而增加;特别是,当离子加宽参数较大时,Mayer模型微场分布函数对Stark加宽和频移的影响异常明显.

  5. Practical electrical engineering

    CERN Document Server

    N Makarov, Sergey; Bitar, Stephen J

    2016-01-01

    This textbook provides comprehensive, in-depth coverage of the fundamental concepts of electrical and computer engineering. It is written from an engineering perspective, with special emphasis on circuit functionality and applications. Reliance on higher-level mathematics and physics, or theoretical proofs has been intentionally limited in order to prioritize the practical aspects of electrical engineering. This text is therefore suitable for a number of introductory circuit courses for other majors such as robotics, mechanical, biomedical, aerospace, civil, architecture, petroleum, and industrial engineering. The authors’ primary goal is to teach the aspiring engineering student all fundamental tools needed to understand, analyze and design a wide range of practical circuits and systems. Their secondary goal is to provide a comprehensive reference, for both major and non-major students as well as practicing engineers. Provides a self-contained, fundamental textbook on electric circuits and basic electronic...

  6. Efficacy Observation on Functional Electrical Stimulation Combined with Rehabilitation Training for Hemiplegic after Stroke%功能性电刺激联合康复训练治疗脑卒中偏瘫疗效观察

    Institute of Scientific and Technical Information of China (English)

    任海; 何永红

    2013-01-01

    Objective: To investigate the efficacy of treating hemiplegic by functional electrical stimulation combined with rehabilitation training. Methods:60 cases of patients were randomly divided into experiment group and control group, on the basis of conventional rehabilitation training, the control adopted the conventional ambulation training, while the experiment group adopted functional electrical stimulation, and compared the effi-cacy of two groups. Results:The improvement of MMT, TUG, 10MWT and Barthel index in experiment group were all better than those in control group (P<0.05). Conclusion:The treatment of functional electrical stimulation combined with rehabilitation training has a great effect on motor func-tion recovery of patients with hemiplegic after stroke, which has a high application value.%  目的:探讨功能性电刺激联合康复训练对脑卒中偏瘫的康复效果。方法:将60例患者随机分为实验组和对照组,对照组在常规恢复性训练基础上增加常规步行训练,实验组则增加功能性电刺激步行训练,比较两组临床疗效。结果:实验组MMT、TUG、10MWT及Barthel指数改善程度均优于对照组(P<0.05)。结论:功能性电刺激联合康复训练对脑卒中偏瘫患者的运动功能恢复效果显著,具有较高的应用价值。

  7. 电针联合生物反馈治疗功能性大便失禁临床观察%The Clinical Observation of Electric Acupuncture Combined With Biofeedback Therapy for Patients With Functional Encopresis

    Institute of Scientific and Technical Information of China (English)

    鲁丹

    2015-01-01

    Objective The study was performed to observe the clinical curative effect of the electric acupuncture combined with biofeedback therapy treatment functional encopresis. Methods 62 patients with functional encopresis were voluntarily divided into two groups: treatment group (32 cases) and control group(30 cases).The treatment group was exposed to the electric acupuncture combined with biofeedback therapy. Patients in the control group only receiced the biofeedback therapy. To observe symptom change of functional encopresis.Results The total effective rate of the two group was 76.67% and 96.88% respectively. The treatment group is better than the control group.Conclusion The electric acupuncture combined with biofeedback therapy plays a positive role in treating functional encopresis.%目的:观察电针联合生物反馈治疗功能性大便失禁的临床疗效。方法患者自愿选择分为治疗组32例与对照组30例,治疗组采用电针联合生物反馈治疗,对照组采用生物反馈治疗,观察大便失禁改善情况。结果治疗组总有效率96.88%,对照组热总有效率76.67%,治疗组优于对照组(P<0.05)。结论电针联合生物反馈治疗功能行大便失禁疗效显著。

  8. High saving potentials and functional enhancements. Diesel-electric hybrid drives in mobile engines; Hohe Einsparpotenziale und funktionale Erweiterungen. Dieselelektrische Hybridantriebe in mobilen Arbeitsmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Dietel, Harald [Sensor-Technik Wiedemann (STW), Kaufbeuren (Germany); Kuhn, Michael; Hemscheidt, Michael [Kaessbohrer, Laupheim (Germany)

    2009-07-01

    With increasing environmental awareness as well as rising fuel prices, the issue of energy efficiency has come into the focus of public interest. Hybrid drives are an interesting option, usually in the form of passenger cars with a spark ignition engine and (at least) one electric motor in a single powertrain involving significant saving potentials and energy resources. Electrification of vehicles offers furtheron possibilities, which conventional systems can't arrive. (orig./GL)

  9. Electrical, Magnetic, and Optical Measurement Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides tools necessary for electrical, magnetic, and optical characterization of bulk and thin-film materials. This includes the ability to determine the...

  10. 7 CFR 1700.28 - Electric Program.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Electric Program. 1700.28 Section 1700.28 Agriculture... GENERAL INFORMATION Agency Organization and Functions § 1700.28 Electric Program. RUS, through the Electric Program, makes loans and loan guarantees for rural electrification and the furnishing of...

  11. Electric Propulsion

    Science.gov (United States)

    Baggett, R.

    2004-11-01

    Next Generation Electric Propulsion (NGEP) technology development tasks are working towards advancing solar-powered electric propulsion systems and components to levels ready for transition to flight systems. Current tasks within NGEP include NASA's Evolutionary Xenon Thruster (NEXT), Carbon Based Ion Optics (CBIO), NSTAR Extended Life Test (ELT) and low-power Hall Effect thrusters. The growing number of solar electric propulsion options provides reduced cost and flexibility to capture a wide range of Solar System exploration missions. Benefits of electric propulsion systems over state-of-the-art chemical systems include increased launch windows, which reduce mission risk; increased deliverable payload mass for more science; and a reduction in launch vehicle size-- all of which increase the opportunities for New Frontiers and Discovery class missions. The Dawn Discovery mission makes use of electric propulsion for sequential rendezvous with two large asteroids (Vesta then Ceres), something not possible using chemical propulsion. NEXT components and thruster system under development have NSTAR heritage with significant increases in maximum power and Isp along with deep throttling capability to accommodate changes in input power over the mission trajectory. NEXT will produce engineering model system components that will be validated (through qualification-level and integrated system testing) and ready for transition to flight system development. NEXT offers Discovery, New Frontiers, Mars Exploration and outer-planet missions a larger deliverable payload mass and a smaller launch vehicle size. CBIO addresses the need to further extend ion thruster lifetime by using low erosion carbon-based materials. Testing of 30-cm Carbon-Carbon and Pyrolytic graphite grids using a lab model NSTAR thruster are complete. In addition, JPL completed a 1000 hr. life test on 30-cm Carbon-Carbon grids. The NSTAR ELT was a life time qualification test started in 1999 with a goal of 88 kg

  12. Electricity unplugged

    Science.gov (United States)

    Karalis, Aristeidis

    2009-02-01

    The judge was driving back late one cold winter night. Entering the garage, the battery-charging indicator in his wirelessly powered electric car came on. "Home at last," crossed his mind. He swiped his personal smartcard on the front-door detector to be let in. He heard a "charging" beep from his mobile phone. The blinking cursor on the half-finished e-mail on the laptop had been waiting all day on the side table. He picked the computer up and walked towards his desk. "Good evening, your honour. Your wirelessly heated robe," said the butler-robot as it approached from the kitchen. Putting on the electric garment, he sat on the medical desk chair. His artificial heart was now beating faster.

  13. Electric monopoly

    Energy Technology Data Exchange (ETDEWEB)

    Norton, C.

    1981-09-14

    A controversial proposal to deregulate a major part of the electric utility industry could transform how electric power is produced. The proposal involves one-third of US energy consumption and violates the classic economic theory that tightly regulated natural monopolies serve society's needs best. Supporters of the proposal suggest that free-market competition may now be valid because new technologies and new power-supply sources can introduce innovation and efficiency into cost control. Many states, for example, allow utilities to pass capital costs through to their users. Alternative energy sources could include small hydro, wind power, and industrial cogeneration. Opponents, who question whether there really is a free market in energy production, suggest better regulation to protect consumers. Some of the opposition will come from utilities wanting to keep their captive markets. (DCK)

  14. Surface functionalization of BiFeO3: A pathway for the enhancement of dielectric and electrical properties of poly(methyl methacrylate)-BiFeO3 composite films

    Science.gov (United States)

    Mishra, Mukesh Kumar; Moharana, Srikanta; Behera, Banarji; Mahaling, Ram Naresh

    2017-03-01

    A novel two-phase composite film is prepared by the solvent casting method employing poly(methyl methacrylate) (PMMA) as polymer matrix and bismuth ferrite (BFO) as ceramic filler. The surfaces of BFO are functionalized by proper hydroxylating agents to activate their chemical nature. The structural analysis of the composite films confirms that the composites made up of functionalized BFO (BFO-OH) have a distorted rhombohedral structure. The morphological analysis shows that BFO-OH particles are equally distributed over the polymer matrix. The -OH functionality of BFO-OH is confirmed by FTIR. The dielectric and electrical studies at a frequency range from 100 Hz to 1 MHz reveal that PMMA-(BFO-OH) composites have enhanced dielectric constant as well as electrical conductivities, much higher than that of unmodified composites. According to the ferroelectric measurement result, the hydroxylated composite film shows a superior ferroelectric behavior than that of the unmodified one, with a remanent polarization (2 P r) of 2.764 μC/cm2.

  15. The Schema Features and Aesthetic Functions of the Foreign Language Teaching with Electric Audio-visual Aids%外语电化教学的图式特征与美育功能

    Institute of Scientific and Technical Information of China (English)

    齐欣

    2015-01-01

    外语电化教学对传统外语教学模式提出挑战的同时,其自身也面临着诸多的挑战,需要更多的理论支撑和功能研究。基于图式理论和美育教育,对外语电化教学图式特征及其隐性、感性、个性三种美育功能的创新审视,进一步丰富了外语电化教学的理论基础,并强调了其美育功能实现的必要性。%While the foreign language teaching with electric audio-visual aids brings about challenges to the traditional language teaching,it is also faced with many challenges,and more studies on its theoretical basis and functions are encouraged. On the basis of Schema Theory and aesthetic education,this paper makes an innovative examination of the schema features of foreign language teaching with electric audio-visual aids and its implicit,emotional,and personalized aesthetic functions,further enriches its theoretical basis and emphasizes the necessity of achieving its aesthetic functions.

  16. Electric Car

    Science.gov (United States)

    1977-01-01

    NASA's Lewis Research Center undertook research toward a practical, economical battery with higher energy density. Borrowing from space satellite battery technology, Lewis came up with a nickel-zinc battery that promises longer life and twice the range of the lead-acid counterpart. Lewis researchers fabricated a prototype battery and installed it in an Otis P-500 electric utility van, using only the battery space already available and allowing battery weight equal to that of the va's conventional lead-acid battery

  17. On the performance of long-range-corrected density functional theory and reduced-size polarized LPol-n basis sets in computations of electric dipole (hyper)polarizabilities of π-conjugated molecules.

    Science.gov (United States)

    Baranowska-Łączkowska, Angelika; Bartkowiak, Wojciech; Góra, Robert W; Pawłowski, Filip; Zaleśny, Robert

    2013-04-05

    Static longitudinal electric dipole (hyper)polarizabilities are calculated for six medium-sized π-conjugated organic molecules using recently developed LPol-n basis set family to assess their performance. Dunning's correlation-consistent basis sets of triple-ζ quality combined with MP2 method and supported by CCSD(T)/aug-cc-pVDZ results are used to obtain the reference values of analyzed properties. The same reference is used to analyze (hyper)polarizabilities predicted by selected exchange-correlation functionals, particularly those asymptotically corrected.

  18. Analysis of biofeedback electrical stimulation combined with vaginal dumbbell on the recovery of postpartum pelvic muscle function%生物反馈电刺激结合阴道哑铃的临床效果浅析

    Institute of Scientific and Technical Information of China (English)

    于爱萍; 闫晓蓉; 王海燕

    2013-01-01

    Objective To assess the effect of biofeedback electrical stimulation combined with Vaginal dumbbell on the recovery of postpartum pelvic muscle function. Methods 122 cases of primiparous women after spontanecus delivery were selected in our hospital from June to September in 2012,who received 42-day recheck by the pelvic floor muscle strength of primary screening at the pelvic of 0 to 3. Then they were randomly divided into investigation group(62 cases) and control group (60 cases).Investigation group applied the low-frequency electrical stimulation combined with biofeedback with vaginal dumbbell. The control group used the low-frequency joint electrical stimulation biofeedback combined with shrinking anal exercises. Pelvic floor muscle strength recovery were compared between 2 groups of Patients after the treatment. Results The pelvic floor muscle strength in two groups of patients recoveried and improved at different level of 0 to 3 was significantly lower than the control group, the difference was statistically significant (P  生物反馈电刺激联合阴道哑铃在产后盆底康复中的治疗效果优于生物反馈电刺激配合单纯缩肛练习,值得临床推广。

  19. Corrosion Protection of Electrically Conductive Surfaces

    OpenAIRE

    Jian Song; Liangliang Wang; Andre Zibart; Christian Koch

    2012-01-01

    The basic function of the electrically conductive surface of electrical contacts is electrical conduction. The electrical conductivity of contact materials can be largely reduced by corrosion and in order to avoid corrosion, protective coatings must be used. Another phenomenon that leads to increasing contact resistance is fretting corrosion. Fretting corrosion is the degradation mechanism of surface material, which causes increasing contact resistance. Fretting corrosion occurs when there is...

  20. Optical and Electrical Properties of Nanostructured Metallic Electrical Contacts

    CERN Document Server

    Toranzos, Victor J; Mochán, W Luis; Zerbino, Jorge O

    2016-01-01

    We study the optical and electrical properties of silver films with a graded thickness obtained through metallic evaporation in vacuum on a tilted substrate to evaluate their use as semitransparent electrical contacts. We measure their ellipsometric coefficients, optical transmissions and electrical conductivity for different widths, and we employ an efficient recursive method to calculate their macroscopic dielectric function, their optical properties and their microscopic electric fields. The topology of very thin films corresponds to disconnected islands, while very wide films are simply connected. For intermediate widths the film becomes semicontinuous, multiply connected, and its microscopic electric field develops hotspots at optical resonances which appear near the percolation threshold of the conducting phase, yielding large ohmic losses that increase the absorptance above that of a corresponding homogeneous film. Optimizing the thickness of the film to maximize its transmittance above the percolation...

  1. A girl with tuberous sclerosis complex presenting with severe epilepsy and electrical status epilepticus during sleep, and with high-functioning autism and mutism.

    Science.gov (United States)

    Pacheva, Iliyana; Panov, Georgi; Gillberg, Christopher; Neville, Brian

    2014-06-01

    Most patients with tuberous sclerosis complex (TSC) suffer from epilepsy, and many have cognitive and behavioral problems like severe intellectual disability, autism, and hyperactivity. Only rare patients with TSC and autism have a normal intelligence quotient. We report a 13-year-old girl with definite TSC who had early-onset severe epilepsy, autistic behavior, and moderate developmental delay. By school age, however, she had normal intelligence; her intelligence quotient was at least 70 based on a Stanford-Binet test that she refused to complete. She showed good reading, writing, and language comprehension skills, and the special abilities of hyperlexia, hypermnesia, and hypercalculia. However, she did not speak. Criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, and her Childhood Autism Rating Scale score of 36 indicated mild to moderate autism. She had severe electroencephalographic abnormalities: hypsarrhythmia, multifocal or generalized epileptiform discharges, and electrical status epilepticus during sleep, with a continuous left temporal focus. Magnetic resonance imaging showed many cortical tubers in all brain lobes, and subependymal nodules. We discuss possible explanations for her lack of speech. Considered as speech apraxia, her mutism could be either a symptom of her TSC or a component of her autism. Another possibility is that long-lasting electrical status epilepticus during sleep led to her autistic behavior and language arrest. Still another possibility is that a disinhibited mammalian target of rapamycin (mTOR) pathway was at the root of all of her neuropsychiatric symptoms.

  2. Climate Action Benefits: Electricity

    Science.gov (United States)

    This page provides background on the relationship between electricity and climate change and describes what the CIRA Electricity analyses cover. It provides links to the subsectors Electricity Demand and Electricity Supply.

  3. Solar Electricity

    Science.gov (United States)

    1988-01-01

    ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

  4. Effects of the South American psychoactive beverage ayahuasca on regional brain electrical activity in humans: a functional neuroimaging study using low-resolution electromagnetic tomography.

    Science.gov (United States)

    Riba, Jordi; Anderer, Peter; Jané, Francesc; Saletu, Bernd; Barbanoj, Manel J

    2004-01-01

    Ayahuasca, a South American psychotropic plant tea obtained from Banisteriopsis caapi and Psychotria viridis, combines monoamine oxidase-inhibiting beta-carboline alkaloids with N,N-dimethyltryptamine (DMT), a psychedelic agent showing 5-HT(2A) agonist activity. In a clinical research setting, ayahuasca has demonstrated a combined stimulatory and psychedelic effect profile, as measured by subjective effect self-assessment instruments and dose-dependent changes in spontaneous brain electrical activity, which parallel the time course of subjective effects. In the present study, the spatial distribution of ayahuasca-induced changes in brain electrical activity was investigated by means of low-resolution electromagnetic tomography (LORETA). Electroencephalography recordings were obtained from 18 volunteers after the administration of a dose of encapsulated freeze-dried ayahuasca containing 0.85 mg DMT/kg body weight and placebo. The intracerebral power density distribution was computed with LORETA from spectrally analyzed data, and subjective effects were measured by means of the Hallucinogen Rating Scale (HRS). Statistically significant differences compared to placebo were observed for LORETA power 60 and 90 min after dosing, together with increases in all six scales of the HRS. Ayahuasca decreased power density in the alpha-2, delta, theta and beta-1 frequency bands. Power decreases in the delta, alpha-2 and beta-1 bands were found predominantly over the temporo-parieto-occipital junction, whereas theta power was reduced in the temporomedial cortex and in frontomedial regions. The present results suggest the involvement of unimodal and heteromodal association cortex and limbic structures in the psychological effects elicited by ayahuasca.

  5. Application of Functional Electrical Stimulation and Brain Computer Interface in Medicine%功能性电刺激与脑机接口在医学中的应用

    Institute of Scientific and Technical Information of China (English)

    隋宝石; 万柏坤

    2011-01-01

    To review the application of functional electrical stimulation (FES) on treatment of motor dysfunction and dysphagia induced by brain or spinal cord injury, and introduce the application of brain computer interface in modern medicine and the progress of BCI-based FES. The results show that BCI, FES and BCI-based FES are good prospect of new technology in modern rehabilitation engineering area.%本文回顾了功能性电刺激(Functional Electrical Stimulation,FES)在治疗脑损伤和脊髓损伤所造成的运动功能和吞咽障碍方面的应用;总结了脑机接口(Brain Computer Interface,BCI)技术在现代医学中的应用以及基于BCI的FES的研究现状.结果 显示,BCI、FES及二者相结合技术在现代康复工程领域中是极具应用前景的新技术.

  6. Design of an electric energy meter with fault monitoring and remote reporting error function%一种具有故障监测及远程报错功能的电能表设计

    Institute of Scientific and Technical Information of China (English)

    沈庆; 瞿遂春; 邱爱兵

    2016-01-01

    文中针对目前市场上单相电子式电能表发生故障不易监测的问题,设计了一种具有自动故障监测及远程报错功能的电能表。本设计采用高精度单相电能计量芯片 ADE7755采集用户所使用的电量,采用高可靠性的RS485传输协议进行数据传输,使用高性能的单片机 STC89C52来作为整个电能采集、故障检测、数据传输电路的控制核心。构建了整个电能计量电路的组成框图、单相电能测量电路图以及软件流程图,最后对样机进行了试验,对试验结果进行了分析,实验结果表明该电能计量电路具有较高的监测精度。%In this paper, we design a power meter with automatic fault monitoring and remote report and error function in the current market. This design using high-precision single-phase electric power measurement chip ADE7755 collection of user and the high reliability of RS485 communication protocol for data transmission, using high performance microcontroller STC89C52 as the electric energy acquisition, fault detection and data transmission circuit control of the core. Construction of the whole electric energy metering circuit composition block diagram, single-phase electric can measuring circuit diagram and software flow chart. Finally, the prototype tests are carried out on the test results were analyzed. The experimental results show that the electric energy metering circuit has high monitoring precision.

  7. 信号式功能性电刺激对脑卒中患者认知功能的影响%Effects of Instructional Functional Electrical Stimulation on Cognitive Deficit in Patients with Stroke

    Institute of Scientific and Technical Information of China (English)

    张安静; 田威; 李丽; 白玉龙; 胡永善; 吴毅; 姜鹭春; 路微波; 徐一鸣; 朱秉

    2011-01-01

    目的:探讨信号式功能性电刺激对脑卒中患者认知功能的影响.方法:脑卒中偏瘫患者34例,分为A组8例、B组8例、C组7例及D组11例,分别配合给予信号式功能性电刺激、国产低频电刺激、肌电反馈电刺激及操作同A组,但无电刺激输出.于治疗前、治疗后20 d时用简易精神评定量表(MMSE)及功能综合评定量表(FCA)的认知部分对各组患者进行精神状态及认知功能评定.结果:经过20 d的治疗,A、C组FCA认知部分和MMSE评分与治疗前及B、D组比较均有明显提高(P<0.05);A组与C组治疗前后的差值比较差异无统计学意义.B、D组与治疗前及治疗后2组间差值比较均差异无统计学意义.结论:信号式功能性电刺激与肌电反馈电刺激治疗均可促进脑卒中患者受损的神经功能恢复,改善情绪障碍,提高认知功能.%Objective: To explore the effects of instructional functional electrical stimulation (IFES) on the cognitive deficit in patients with stroke.Methods: Thirty-four patients with stroke were randomly divided into four groups as follows: the IFES group, the traditional electrical stimulation (TES) group, the electromyogram-triggered neuromuscular stimulation (ETNS) group and the no electrical stimulation group.All the subjects received the same rehabilitation training and internal medicine treatment.Besides, the patients in IFES, TES and ETNS groups were given a 20-day program of electrical stimulation to the extensor muscles of wrist (20 min/day, 5 days a week) via surface electrodes.All subjects were assessed with the cognitive part of the functional comprehensive assessment (FCA) and the mini-mental state examination (MMSE) before and at the 20th day after treatment.Results: No significant differences were found in every rating scale among the groups at the recruitment.After treatment for 20 days, every group made progress in some extent, especially in the IFES group and the ETNS group (P<0.05).On the

  8. Electrically driven optical metamaterials

    Science.gov (United States)

    Le-van, Quynh; Le Roux, Xavier; Aassime, Abdelhanin; Degiron, Aloyse

    2016-06-01

    The advent of metamaterials more than 15 years ago has offered extraordinary new ways of manipulating electromagnetic waves. Yet, progress in this field has been unequal across the electromagnetic spectrum, especially when it comes to finding applications for such artificial media. Optical metamaterials, in particular, are less compatible with active functionalities than their counterparts developed at lower frequencies. One crucial roadblock in the path to devices is the fact that active optical metamaterials are so far controlled by light rather than electricity, preventing them from being integrated in larger electronic systems. Here we introduce electroluminescent metamaterials based on metal nano-inclusions hybridized with colloidal quantum dots. We show that each of these miniature blocks can be individually tuned to exhibit independent optoelectronic properties (both in terms of electrical characteristics, polarization, colour and brightness), illustrate their capabilities by weaving complex light-emitting surfaces and finally discuss their potential for displays and sensors.

  9. Electrically driven optical metamaterials.

    Science.gov (United States)

    Le-Van, Quynh; Le Roux, Xavier; Aassime, Abdelhanin; Degiron, Aloyse

    2016-06-22

    The advent of metamaterials more than 15 years ago has offered extraordinary new ways of manipulating electromagnetic waves. Yet, progress in this field has been unequal across the electromagnetic spectrum, especially when it comes to finding applications for such artificial media. Optical metamaterials, in particular, are less compatible with active functionalities than their counterparts developed at lower frequencies. One crucial roadblock in the path to devices is the fact that active optical metamaterials are so far controlled by light rather than electricity, preventing them from being integrated in larger electronic systems. Here we introduce electroluminescent metamaterials based on metal nano-inclusions hybridized with colloidal quantum dots. We show that each of these miniature blocks can be individually tuned to exhibit independent optoelectronic properties (both in terms of electrical characteristics, polarization, colour and brightness), illustrate their capabilities by weaving complex light-emitting surfaces and finally discuss their potential for displays and sensors.

  10. Decentralized adaptive robust control based on sliding mode and nonlinear compensator for the control of ankle movement using functional electrical stimulation of agonist-antagonist muscles

    Science.gov (United States)

    Kobravi, Hamid-Reza; Erfanian, Abbas

    2009-08-01

    A decentralized control methodology is designed for the control of ankle dorsiflexion and plantarflexion in paraplegic subjects with electrical stimulation of tibialis anterior and calf muscles. Each muscle joint is considered as a subsystem and individual controllers are designed for each subsystem. Each controller operates solely on its associated subsystem, with no exchange of information between the subsystems. The interactions between the subsystems are taken as external disturbances for each isolated subsystem. In order to achieve robustness with respect to external disturbances, unmodeled dynamics, model uncertainty and time-varying properties of muscle-joint dynamics, a robust control framework is proposed which is based on the synergistic combination of an adaptive nonlinear compensator with a sliding mode control and is referred to as an adaptive robust control. Extensive simulations and experiments on healthy and paraplegic subjects were performed to demonstrate the robustness against the time-varying properties of muscle-joint dynamics, day-to-day variations, subject-to-subject variations, fast convergence, stability and tracking accuracy of the proposed method. The results indicate that the decentralized robust control provides excellent tracking control for different reference trajectories and can generate control signals to compensate the muscle fatigue and reject the external disturbance. Moreover, the controller is able to automatically regulate the interaction between agonist and antagonist muscles under different conditions of operating without any preprogrammed antagonist activities.

  11. Regulation of the Deposition Morphology of Inkjet-Printed Crystalline Materials via Polydopamine Functional Coatings for Highly Uniform and Electrically Conductive Patterns.

    Science.gov (United States)

    Liu, Liang; Ma, Siyuan; Pei, Yunheng; Xiong, Xiao; Sivakumar, Preeth; Singler, Timothy J

    2016-08-24

    We report a method to achieve highly uniform inkjet-printed silver nitrate (AgNO3) and a reactive silver precursor patterns on rigid and flexible substrates functionalized with polydopamine (PDA) coatings. The printed AgNO3 patterns on PDA-coated substrates (glass and polyethylene terephthalate (PET)) exhibit a narrow thickness distribution ranging between 0.9 and 1 μm in the line transverse direction and uniform deposition profiles in the line axial direction. The deposited reactive silver precursor patterns on PDA-functionalized substrates also show "dome-shaped" morphology without "edge-thickened" structure due to "coffee-stain" effect. We posit that the highly uniform functional ink deposits formed on PDA-coated substrates are attributable to the strong binding interaction between the abundant catecholamine moieties at the PDA surface and the metallic silver cations (Ag(+) or Ag(NH3)(2+)) in the solutal inks. During printing of the ink rivulet and solvent evaporation, the substrate-liquid ink (S-L) interface is enriched with the silver-based cations and a solidification at the S/L interface is induced. The preferential solidification initiated at the S-L interface is further verified by the in situ visualization of the dynamic solidification process during solvent evaporation, and results suggest an enhanced crystal nucleation and growth localized at the S-L interface on PDA functionalized substrates. This interfacial interaction mediates solute transport in the liquid phase, resulting in the controlled enrichment of solute at the S-L interface and mitigated solute precipitation in both the contact line region and the liquid ink-vapor (L-V) interface due to evaporation. This mediated transport contributes to the final uniform solid deposition for both types of ink systems. This technique provides a complementary strategy for achieving highly uniform inkjet-printed crystalline structures, and can serve as an innovative foundation for high-precision additive

  12. Electric field distribution of electron emitter surfaces

    Science.gov (United States)

    Tagawa, M.; Takenobu, S.; Ohmae, N.; Umeno, M.

    1987-03-01

    The electric field distribution of a tungsten field emitter surface and a LaB6 thermionic emitter surface has been studied. The computer simulation of electric field distribution on the emitter surface was carried out with a charge simulation method. The electric field distribution of the LaB6 thermionic emitter was experimentally evaluated by the Schottky plot. Two independent equations are necessary for obtaining local electric field and work function; the Fowler-Nordheim equation and the equation of total energy distribution of emitted electron being used to evaluate the electric field distribution of the tungsten field emitter. The experimental results agreed with the computer simulation.

  13. Electric Vehicle Charging Modeling

    OpenAIRE

    Grahn, Pia

    2014-01-01

    With an electrified passenger transportation fleet, carbon dioxide emissions could be reduced significantly depending on the electric power production mix. Increased electric power consumption due to electric vehicle charging demands of electric vehicle fleets may be met by increased amount of renewable power production in the electrical systems. With electric vehicle fleets in the transportation system there is a need for establishing an electric vehicle charging infrastructure that distribu...

  14. The therapeutic effects of functional electrical stimulation in female urinary incontinence%功能性电刺激治疗63例女性尿失禁患者的疗效观察

    Institute of Scientific and Technical Information of China (English)

    刘康; 陈安强

    2008-01-01

    Objective To investigate the therapeutic effectiveness of functional electrical stimulation in the treatment of female urinary incontinence. Methods Sixty-three female patients with urinary incontinence were recruited and treated with functional electrical stimulation delivered by specially-designed vaginal electrodes for 15 to 20 minutes once daily,3 times a week for 8 weeks.Subjective feelings and a urination dairy were recorded to assess the effect of the treatment. Results Daily urinations and residual volumes decreased,and feelings of urgency were alleviated after treatment,while the voiding volume and control of urine flow were significantly improved.No significant side effects were observed. Conclusion Functional electrical stimulation is significantly effective in treating female urinary incontinence.%目的 观察神经功能性电刺激治疗女性尿失禁患者的疗效.方法 共选取63例女性尿失禁患者,采用AM800型神经功能重建工作站系统对其进行功能性电刺激,连续进行8周电刺激.于治疗前、治疗1周、6周及8周时采用主观感觉、排尿日记、护垫测试、B超检查、尿动力学检查等进行疗效评定.结果 上述63例女性患者经相应治疗后,其各项疗效指标均有不同程度改善,与治疗前比较,差异均有统计学意义(P<0.05);并且在治疗过程中均未发现明显不良反应.结论 神经功能性电刺激对尿失禁患者具有显著疗效,值得临床推广、应用.

  15. Density functional theory investigation of hydrogen bonding effects on the oxygen, nitrogen and hydrogen electric field gradient and chemical shielding tensors of anhydrous chitosan crystalline structure.

    Science.gov (United States)

    Esrafili, Mehdi D; Elmi, Fatemeh; Hadipour, Nasser L

    2007-02-08

    A systematic computational investigation was carried out to characterize the 17O, 14N and 2H electric field gradient, EFG, as well as 17O, 15N, 13C and 1H chemical shielding tensors in the anhydrous chitosan crystalline structure. To include the hydrogen-bonding effects in the calculations, the most probable interacting molecules with the target molecule in the crystalline phase were considered through a hexameric cluster. The computations were performed with the B3LYP method and 6-311++G(d,p) and 6-31++G(d,p) standard basis sets using the Gaussian 98 suite of programs. Calculated EFG and chemical shielding tensors were used to evaluate the 17O, 14N and 2H nuclear quadrupole resonance, NQR, and 17O, 15N, 13C and 1H nuclear magnetic resonance, NMR, parameters in the hexameric cluster, which are in good agreement with the available experimental data. The difference between the calculated NQR and NMR parameters of the monomer and hexamer cluster shows how much hydrogen bonding interactions affect the EFG and chemical shielding tensors of each nucleus. These results indicate that both O(3)-H(33)...O(5-3) and N-H(22)...O(6-4) hydrogen bonding have a major influence on NQR and NMR parameters. Also, the quantum chemical calculations indicate that the intra- and intermolecular hydrogen bonding interactions play an essential role in determining the relative orientation of EFG and chemical shielding principal components in the molecular frame axes.

  16. Topics on electricity trade

    Energy Technology Data Exchange (ETDEWEB)

    Skytte, K.

    2001-07-01

    being unable to fulfil the commitments made on the spot market. The disclosed cost of using the regulating power market is a quadratic function of the amount of regulation. This asymmetric cost may encourage bidders with fluctuating production to be more strategic in their way of bidding on the spot market. By using such strategies the extra costs (for e.g. wind power) needed to counter unpredictable fluctuations may be limited. The fourth paper applies the findings in the previous paper to show how a supplier with a 'controllable' production will make strategic bids on the power exchange - in this case a heat pump. The fifth paper discusses the design of the regulating power market and what the choice of design means for suppliers with fluctuating production, e.g. wind turbines. It is found that not only does the accuracy of the wind prediction influence the use of the power exchange, but the structure of the power exchange itself may also play an important role. Several studies of the northern European electricity liberalisation have concluded that developments of a liberalised electricity market and cross border trade can be of benefit for the consumers and bring along a global environmental improvement. All these studies have assumed that a perfect competitive electricity market can be obtained. A number of imperfections, which inevitably will arise, have not been taken into account, - at least in the transition period. These imperfections can be technical, economic or tradition-bound, but may have political characteristics as well. The sixth paper in this thesis surveys those market imperfections which are most likely to appear. Market imperfections can, for example, have structural or political characteristics that imply non-optimal competitive behaviour, e.g., the means to achieve political goals may hinder the desirable effects of the liberalisation. This can, for example, come from the creation of suitable arrangements for survival and enlargement of

  17. Electricity supply contracts: Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, G.; Vezzoni, M.; Grassani, E. (Sistemi Integrati per il Risparmio Energetico, Pavia (Italy) Necchi Compressori, Pavia (Italy))

    1991-10-01

    This paper presents a computer program, ACEE (Electrical Energy Consumption Analysis), developed to assist industrial firms in Italy to determine their electrical power consumption, optimize it through production process interventions, and then utilize the results to draft up optimum electricity supply contracts with ENEL (Italian National Electricity Board). The program also allows the user to properly budget future allocations for electricity costs.

  18. Effects of neuromuscular electrical stimulation and aerobic exercise training on arterial stiffness and autonomic functions in patients with chronic heart failure.

    Science.gov (United States)

    Dobšák, Petr; Tomandl, Josef; Spinarova, Lenka; Vitovec, Jiri; Dusek, Ladislav; Novakova, Marie; Jarkovsky, Jiri; Krejci, Jan; Hude, Petr; Honek, Tomáš; Siegelova, Jarmila; Homolka, Pavel

    2012-10-01

    Neuromuscular electrical stimulation (NMES) of leg muscles has been introduced in clinical practice as a rehabilitation (RHB) method in patients with chronic heart failure (CHF); however, the role of NMES on the reduction of arterial stiffness and autonomic disbalance in these patients has not yet been studied. Sixty-one patients with stable CHF (mean age 58.9 [2.1] years; mean ejection fraction 31 [4.2]%, New York Heart Association II-III) were randomly assigned into two groups. Patients in (i) exercise training group (ET; n = 30) underwent 12 weeks of bicycle ET (3 × 40 min/week); (ii) group NMES (n = 31) performed 12 weeks of NMES of quadriceps and calf muscles (frequency 10 Hz, mode "20 s on-20 s off," intensity 60 mA), 2 × 60 min/day. Noninvasive assessment of arterial stiffness was done using the cardio-ankle vascular index (CAVI). CAVI and heart rate variability (HRV) and ·VO(2peak) were evaluated before and after RHB program. Both types of RHB reduced significantly CAVI (ET from 9.6 [0.2] to 8.9 [0.2], P < 0.012; NMES from 9.3 [0.2] to 8.7 [0.2], P < 0.013), increased high frequency (HF) component of HRV (+65.6%; P = 0.001) and decreased ratio of low frequency (LF) component with HF component (LF/HF ratio) in group ET (-39.8%; P < 0.001). Changes of HRV parameters in group NMES were not significant; however, a marked tendency to autonomic stabilization was present. Both types of RHB led also to significant increase of ·VO(2peak) (ET from 18.7 [0.7] to 20.8 [0.7] mL/kg/min, P < 0.004; NMES from 17.3 [0.7] to 19.0 [0.7] mL/kg/min, P < 0.001). ET or NMES has been shown to improve significantly arterial stiffness and to stabilize autonomic balance.

  19. Large electric-potential bias in an EDO-TTF tetramer as a major mechanism of charge ordering observed in its PF6 salt: A density functional theory study

    Science.gov (United States)

    Iwano, Kaoru; Shimoi, Yukihiro

    2008-02-01

    Based on density functional theory, we investigate the electronic structures of an organic molecular solid, (EDO-TTF)2PF6 (EDO-TTF=ethylendioxy-tetrathiafulvalene) , which is known to have a so-called charge-ordered state below a critical temperature. While it has been thought that the origins of the charge ordering are molecular deformations, we find that an electric potential bias within a tetramer of EDO-TTF molecules is close to 1eV , originating from long-range Coulombic interactions with surrounding molecules, and that it is essential in reproducing the actual degree of charge ordering. We also calculate optical conductivity spectra and find a good consistency with experimental results.

  20. Leaking electricity in domestic appliances

    Energy Technology Data Exchange (ETDEWEB)

    Meier, Alan; Rosen, Karen

    1999-05-01

    Many types of home electronic equipment draw electric power when switched off or not performing their principal functions. Standby power use (or ''leaking electricity'') for most appliances ranges from 1 - 20 watts. Even though standby use of each device is small, the combined standby power use of all appliances in a home can easily exceed 50 watts. Leaking electricity is already responsible for 5 to 10 percent of residential electricity use in the United States and over 10 percent in Japan. An increasing number of white goods also have standby power requirements. There is a growing international effort to limit standby power to around one watt per device. New and existing technologies are available to meet this target at little or no extra cost.

  1. In Situ TEM Electrical Measurements

    DEFF Research Database (Denmark)

    Canepa, Silvia; Alam, Sardar Bilal; Ngo, Duc-The

    2016-01-01

    Transmission electron microscopy (TEM) offers high spatial and temporal resolution that provides unique information for understanding the function and properties of nanostructures on their characteristic length scales. Under controlled environmental conditions and with the ability to dynamically...... influence the sample by external stimuli, e.g. through electrical connections, the TEM becomes a powerful laboratory for performing quantitative real time in situ experiments. Such TEM setups enable the characterization of nanostructures and nanodevices under working conditions, thereby providing a deeper...... materials and devices with the specimen being contacted by electrical, mechanical or other means, with emphasis on in situ electrical measurements performed in a gaseous or liquid environment. We will describe the challenges and prospects of electrical characterization of devices and processes induced...

  2. The course and the anatomo-functional relationships of the optic radiation: a combined study with ‘post mortem’ dissections and ‘in vivo’ direct electrical mapping

    Science.gov (United States)

    Sarubbo, Silvio; De Benedictis, Alessandro; Milani, Paola; Paradiso, Beatrice; Barbareschi, Mattia; Rozzanigo, Umbero; Colarusso, Enzo; Tugnoli, Valeria; Farneti, Marco; Granieri, Enrico; Duffau, Hugues; Chioffi, Franco

    2015-01-01

    Even if different dissection, tractographic and connectivity studies provided pure anatomical evidences about the optic radiations (ORs), descriptions of both the anatomical structure and the anatomo-functional relationships of the ORs with the adjacent bundles were not reported. We propose a detailed anatomical and functional study with ‘post mortem’ dissections and ‘in vivo’ direct electrical stimulation (DES) of the OR, demonstrating also the relationships with the adjacent eloquent bundles in a neurosurgical ‘connectomic’ perspective. Six human hemispheres (three left, three right) were dissected after a modified Klingler's preparation. The anatomy of the white matter was analysed according to systematic and topographical surgical perspectives. The anatomical results were correlated to the functional responses collected during three resections of tumours guided by cortico-subcortical DES during awake procedures. We identified two groups of fibres forming the OR. The superior component runs along the lateral wall of the occipital horn, the trigone and the supero-medial wall of the temporal horn. The inferior component covers inferiorly the occipital horn and the trigone, the lateral wall of the temporal horn and arches antero-medially to form the Meyer's Loop. The inferior fronto-occipital fascicle (IFOF) covers completely the superior OR along its entire course, as confirmed by the subcortical DES. The inferior longitudinal fascicle runs in a postero-anterior and inferior direction, covering the superior OR posteriorly and the inferior OR anteriorly. The IFOF identification allows the preservation of the superior OR in the anterior temporal resection, avoiding post-operative complete hemianopia. The identification of the superior OR during the posterior temporal, inferior parietal and occipital resections leads to the preservation of the IFOF and of the eloquent functions it subserves. The accurate knowledge of the OR course and the relationships

  3. Corrosion Protection of Electrically Conductive Surfaces

    Directory of Open Access Journals (Sweden)

    Jian Song

    2012-11-01

    Full Text Available The basic function of the electrically conductive surface of electrical contacts is electrical conduction. The electrical conductivity of contact materials can be largely reduced by corrosion and in order to avoid corrosion, protective coatings must be used. Another phenomenon that leads to increasing contact resistance is fretting corrosion. Fretting corrosion is the degradation mechanism of surface material, which causes increasing contact resistance. Fretting corrosion occurs when there is a relative movement between electrical contacts with surfaces of ignoble metal. Avoiding fretting corrosion is therefore extremely challenging in electronic devices with pluggable electrical connections. Gold is one of the most commonly used noble plating materials for high performance electrical contacts because of its high corrosion resistance and its good and stable electrical behavior. The authors have investigated different ways to minimize the consumption of gold for electrical contacts and to improve the performance of gold plating. Other plating materials often used for corrosion protection of electrically conductive surfaces are tin, nickel, silver and palladium. This paper will deal with properties and new research results of different plating materials in addition to other means used for corrosion protection of electrically conductive surfaces and the testing of corrosion resistance of electrically conductive surfaces.

  4. Electric and Hybrid Electric Vehicle Technologies

    Science.gov (United States)

    2007-11-02

    electric vehicles .10 In 1994, BART chose the bid submitted by U.S. Electricar to provide 45 converted Geo Prisms and to be the turnkey operator. However...Declining to Sign Contracts Rank (1 = highest) => 1 2 3 4 Cost too much per month (10) 6 2 1 1 Want to buy , not lease, an electric vehicle (4) 2 1...District DEFENSE ADVANCED RESEARCH PROJECTS AGENCY ELECTRIC AND HYBRID ELECTRIC VEHICLE TECHNOLOGIES COOPERATIVE AGREEMENT MDA972-93-1-0027 QUARTERLY

  5. The Electric Car Challenge.

    Science.gov (United States)

    Diehl, Brian E.

    1997-01-01

    Describes the Electric Car Challenge during which students applied methods of construction to build lightweight, strong vehicles that were powered by electricity. The activity required problem solving, sheet metal work, electricity, design, and construction skills. (JOW)

  6. Analysis of the electrical characteristics of Zn/ZnSe/n-Si/Au-Sb structure fabricated using SILAR method as a function of temperature

    Energy Technology Data Exchange (ETDEWEB)

    Guezeldir, B. [Department of Physics, Faculty of Sciences, University of Atatuerk, 25240 Erzurum (Turkey); Saglam, M., E-mail: msaglam@atauni.edu.t [Department of Physics, Faculty of Sciences, University of Atatuerk, 25240 Erzurum (Turkey); Ates, A. [Department of Physics, Faculty of Sciences, University of Atatuerk, 25240 Erzurum (Turkey)

    2010-09-10

    The Successive Ionic Layer Adsorption and Reaction (SILAR) method has been used to deposit ZnSe thin film onto Si substrate to obtain the Zn/ZnSe/n-Si/Au-Sb sandwich structure. The X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) methods are used to investigate the structural and morphological properties of films. The XRD and SEM studies reveal that the films are covered well on Si substrate and have good polycrystalline structure and crystalline levels. The current-voltage (I-V) and capacitance-voltage (C-V) characteristics of this structure have been investigated as a function of the temperature (80-300 K) with 20 K steps. The ideality factor (n) and zero-bias barrier height ({Phi}{sub b0}) value which obtained from I-V curves were found to be strongly temperature dependent. While {Phi}{sub b0} increases with increasing temperature, n decreases. This behavior of the {Phi}{sub b0} and n can be attributed to barrier inhomogeneities at the metal-semiconductor (M-S) interface. The temperature dependence of the I-V characteristics of the Zn/ZnSe/n-Si/Au-Sb structure can reveal the existence of a double Gaussian distribution. The mean barrier height and the Richardson constant values are obtained as 0.925 eV and 1.140 eV, 130 A/cm{sup 2} K{sup 2} and 127 A/cm{sup 2} K{sup 2}, from the modified Richardson plot, respectively. Furthermore, the barrier height and carrier concentration are calculated from reverse bias C{sup -2}-V measurements at 200 kHz frequency as a function of the temperature.

  7. Electrical engineer's reference book

    CERN Document Server

    Laughton, M A

    1985-01-01

    Electrical Engineer's Reference Book, Fourteenth Edition focuses on electrical engineering. The book first discusses units, mathematics, and physical quantities, including the international unit system, physical properties, and electricity. The text also looks at network and control systems analysis. The book examines materials used in electrical engineering. Topics include conducting materials, superconductors, silicon, insulating materials, electrical steels, and soft irons and relay steels. The text underscores electrical metrology and instrumentation, steam-generating plants, turbines

  8. Electrical safety guidelines

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The Electrical Safety Guidelines prescribes the DOE safety standards for DOE field offices or facilities involved in the use of electrical energy. It has been prepared to provide a uniform set of electrical safety standards and guidance for DOE installations in order to affect a reduction or elimination of risks associated with the use of electrical energy. The objectives of these guidelines are to enhance electrical safety awareness and mitigate electrical hazards to employees, the public, and the environment.

  9. DOE handbook electrical safety

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    Electrical Safety Handbook presents the Department of Energy (DOE) safety standards for DOE field offices or facilities involved in the use of electrical energy. It has been prepared to provide a uniform set of electrical safety guidance and information for DOE installations to effect a reduction or elimination of risks associated with the use of electrical energy. The objectives of this handbook are to enhance electrical safety awareness and mitigate electrical hazards to employees, the public, and the environment.

  10. ELECTRIC MOTOR CARS.

    Science.gov (United States)

    PASSENGER VEHICLES , ELECTRIC MOTORS), FEASIBILITY STUDIES, BATTERY COMPONENTS, ELECTRIC BATTERIES, FUEL CELLS, ENERGY CONVERSION, NUCLEAR ENERGY, THERMIONIC CONVERTERS , THERMOELECTRICITY, POWER EQUIPMENT, COSTS

  11. Optical and electrical properties of nanostructured metallic electrical contacts

    Science.gov (United States)

    Toranzos, Victor J.; Ortiz, Guillermo P.; Mochán, W. Luis; Zerbino, Jorge O.

    2017-01-01

    We study the optical and electrical properties of silver films with a graded thickness obtained through metallic evaporation in vacuum on a tilted substrate to evaluate their use as semitransparent electrical contacts. We measure their ellipsometric coefficients, optical transmissions and electrical conductivity for different widths, and we employ an efficient recursive method to calculate their macroscopic dielectric function, their optical properties and their microscopic electric fields. The topology of very thin films corresponds to disconnected islands, while very wide films are simply connected. For intermediate widths the film becomes semicontinuous, multiply connected, and its microscopic electric field develops hotspots at optical resonances which appear near the percolation threshold of the conducting phase, yielding large ohmic losses that increase the absorptance above that of a corresponding homogeneous film. Optimizing the thickness of the film to maximize its transmittance above the percolation threshold of the conductive phase we obtained a film with transmittance T  =  0.41 and a sheet resistance Rs\\text{max}≈ 2.7 Ω . We also analyze the observed emission frequency shift of porous silicon electroluminescent devices when Ag films are used as solid electrical contacts in replacement of electrolytic ones.

  12. Review on Automotive Power Generation System on Plug-in Hybrid Electric Vehicles & Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Leong Yap Wee

    2016-01-01

    Full Text Available Regenerative braking is a function to recharge power bank on the Plug-in electric vehicles (PHEV and electric vehicles (EV. The weakness of this system is, it can only perform its function when the vehicle is slowing down or by stepping the brake foot pedal. In other words, the electricity recharging system is inconsistent, non-continuous and geography dependent. To overcome the weakness of the regenerative braking system, it is suggested that to apply another generator which is going to be parallel with the regenerative braking system so that continuous charging can be achieved. Since the ironless electricity generator has a less counter electromotive force (CEMF comparing to an ironcored electricity generator and no cogging torque. Applying the ironless electricity generator parallel to the regenerative braking system is seen one of the options which creates sustainable charging system compared to cored electricity generator.

  13. Uncertainty contribution of a wind turbine to the electric field of a DVOR antenna as a function of wind direction and rotor position

    Science.gov (United States)

    Sandmann, Sergei; Garbe, Heyno

    2016-09-01

    The presence of a wind turbine (WT) has the potential to distort electromagnetic fields emitted by terrestrial radio navigation aids. In this paper especially the field distortion of a Doppler Very High Frequency Omnidirectional Radio Range (DVOR) surveillance navigation system is investigated as a function of wind direction and rotor position. Therefor, the field distribution of a DVOR is simulated in the surrounding of a WT for 104 combinations of the angles of wind direction and rotor position. Furthermore, these calculations are executed for two different rotor diameters and 10 steps of distance between DVOR and WT in the range of 10 km. Based on the calculated data a method to estimate the maximum field distortion is developed. It is shown that the presented method allows to approximate the worst case field distortion with the results of two general simulation setups. Eliminating the need of simulating all possible geometric constellations of the WT this method hereby offers the benefit of significantly reduced simulation effort.

  14. Dynamics of an electric dipole moment in a stochastic electric field.

    Science.gov (United States)

    Band, Y B

    2013-08-01

    The mean-field dynamics of an electric dipole moment in a deterministic and a fluctuating electric field is solved to obtain the average over fluctuations of the dipole moment and the angular momentum as a function of time for a Gaussian white-noise stochastic electric field. The components of the average electric dipole moment and the average angular momentum along the deterministic electric-field direction do not decay to zero, despite fluctuations in all three components of the electric field. This is in contrast to the decay of the average over fluctuations of a magnetic moment in a stochastic magnetic field with Gaussian white noise in all three components. The components of the average electric dipole moment and the average angular momentum perpendicular to the deterministic electric-field direction oscillate with time but decay to zero, and their variance grows with time.

  15. Integrating The Non-Electrical Worker Into The Electrical Safety Program

    Energy Technology Data Exchange (ETDEWEB)

    Mills, T. David; McAlhaney, John H.

    2012-08-17

    The intent of this paper is to demonstrate an electrical safety program that incorporates all workers into the program, not just the electrical workers. It is largely in response to a paper presented at the 2012 ESW by Lanny Floyd entitled "Facilitating Application of Electrical Safety Best Practices to "Other" Workers" which requested all attendees to review their electrical safety program to assure that non-electrical workers were protected as well as electrical workers. The referenced paper indicated that roughly 50% of electrical incidents involve workers whose primary function is not electrical in nature. It also encouraged all to "address electrical safety for all workers and not just workers whose job responsibilities involve working on or near energized electrical circuits." In this paper, a program which includes specific briefings to non-electrical workers as well as to workers who may need to perform their normal activities in proximity to energized electrical conductors is presented. The program uses a targeted approach to specific areas such as welding, excavating, rigging, chart reading, switching, cord and plug equipment and several other general areas to point out hazards that may exist and how to avoid them. NFPA 70E-2004 was incorporated into the program several years ago and with it the need to include the "other" workers became apparent. The site experience over the years supports the assertion that about half of the electrical incidents involve non-electrical workers and this prompted us to develop specific briefings to enhance the knowledge of the non-electrical worker regarding safe electrical practices. The promotion of "May is Electrical Safety Month" and the development of informative presentations which are delivered to the general site population as well as electrical workers have greatly improved the hazards awareness status of the general worker on site.

  16. 辅以功能电刺激的实时步态训练与反馈分析系统%Real-time Gait Training System with Embedded Functional Electrical Stimulation

    Institute of Scientific and Technical Information of China (English)

    顾琳燕; 阮兆明; 贾桂锋; 夏静; 裘利坚; 吴长旺; 金肖青; 宁钢民

    2015-01-01

    To solve the problem that mostly gait analysis is independent from the treatment, this work proposes a system that integrates the functions of gait training and assessment for foot drop treatment. The system uses a set of sensors to col ect gait parameters and designes multi-mode functional electrical stimulators as actuator. Body area network technology is introduced to coordinate the data communication and execution of the sensors and stimulators, synchronize the gait analysis and foot drop treatment. Bluetooth 4.0 is applied to low the power consumption of the system. The system realizes the synchronization of treatment and gait analysis. It is able to acquire and analyze the dynamic parameters of ankle, knee and hip in real-time, and treat patients by guiding functional electrical stimulation delivery to the specific body locations of patients.%该文研究设计了同步实现足下垂患者步态训练和康复评估的综合系统,以解决目前存在的足下垂治疗与步态分析分离的不足。系统采用多传感器采集各运动部位的参数,并设计了多重模式的功能性电刺激装置,引入了体域网技术协调传感器和刺激器的数据通讯及控制,同步实现步态实时分析与足下垂治疗。体域网应用了蓝牙4.0技术以降低系统功耗。系统实现了治疗与评估的同步,能够实时采集并分析训练时踝、膝、髋等部位运动参数,并同时对患病部位进行功能性电刺激治疗。

  17. Development of brain computer interface technology and its application prospect in brain control animals%脑-机接口技术发展现状及脑控动物应用前景

    Institute of Scientific and Technical Information of China (English)

    孙中磊; 刘英富; 涂悦; 杨凯; 程远驰; 刚琳; 陈旭义; 陈锋

    2016-01-01

    The study of brain-machine interfaces ( BMI) based on humans or animals is expected to improve the living conditions of patients with brain injury, nervous system disease and limb movement disorders.Considerable progress has been made over the past ten years, which is gradually being used to address the long-term and stability issues of BMIs technology.The result of study on safety and security of BMIs has led to the appearance of brain control animals.In this paper, the development of BMI technology and the application prospects of brain control animals are reviewed.%通过基于人或动物的脑机接口技术( brain-machine interfaces,BMI)的研究,有望改善脑损伤、神经系统疾病及肢体运动障碍等患者的生活状态。在过去10年中BMI已取得了相当大的进展,正在逐步解决技术的长期性、稳定性的相关问题。其中BMI在安全、安保方面的研究成果当属“脑控动物”的出现。该文就BMI技术发展现状及“脑控动物”应用前景展开综述。

  18. General Relativity in Electrical Engineering

    OpenAIRE

    Leonhardt, Ulf; Philbin, Thomas G.

    2006-01-01

    In electrical engineering metamaterials have been developed that offer unprecedented control over electromagnetic fields. Here we show that general relativity lends the theoretical tools for designing devices made of such versatile materials. Given a desired device function, the theory describes the electromagnetic properties that turn this function into fact. We consider media that facilitate space-time transformations and include negative refraction. Our theory unifies the concepts operatin...

  19. Analysis and Research on the Function Demand of the Prefecture-county Integrated Electricity Measuring System%电能量计量系统地县一体功能需求分析与研究

    Institute of Scientific and Technical Information of China (English)

    巫志平

    2014-01-01

    Electricity metering system is an automation system for the collection and statistics of substation power supply and demand. It not only provides real-time data for the production, operation monitoring and analysis system but also supports massive data for the forefront research on big data management and cloud computing applications. The completed power system consists of energy meter, collector, communication channels and electricity measuring main station system which is the heart of the system. The prefecture-county integrated electricity measuring system is currently promoted in the grid system. The system functional requirements is designed in the operation and maintenance mode of the prefecture-county integrated, including the web browser interface, report generation, data error correction and requirement analysis on the lack of interaction with distribution system.For this, complex needs of data processing can be adapted increasingly while system maintenance workloads can be reduced.%电能量计量系统是用来采集和统计变电站电力电量供需状况的自动化系统,不仅为生产、运营监控分析系统提供实时数据,还可以为正处于前沿研究的大数据管理、云计算应用提供海量数据支撑。完整的电能量系统由电能表、采集器、通信通道、电能量计量主站系统构成,主站系统处于核心地位。目前,电网系统内正推广建设地县一体电量系统。探讨在地县一体运行维护模式下,对系统功能需求进行设计,包括Web界面浏览、报表生成、数据纠错及与营配系统交互功能不足进行需求分析,在减轻系统维护工作量的同时适应日益复杂的数据处理需求。

  20. Eletroestimulação seletiva mantem estrutura e função do tibial anterior desnervado de ratos Structure and function of denervated tibialis anteriores are maintained by electrical stimulation in rats

    Directory of Open Access Journals (Sweden)

    Juliana de Tillio Polônio

    2010-01-01

    Full Text Available OBJETIVO: A eletroestimulação para tratamento de músculos desnervados deve ser aplicada através do tratamento seletivo. Este estudo avaliou o efeito da eletroestimulação seletiva do músculo desnervado sobre sua estrutura e função. MÉTODOS: Foram utilizados cinqüenta ratos Wistar distribuídos em controle, desnervado estimulado e desnervado não-estimulado. Após avaliação eletrodiagnóstica de estímulo pré-desnervação, os animais sofreram desnervação proximal completa do músculo tibial anterior unilateral. Houve reavaliação semanal para adaptação dos parâmetros de tratamento seletivo, aplicado três vezes por semana. Os animais foram mortos após 7, 14, 28 e 56 dias do pós-cirúrgico. Foram realizados procedimentos histoquímicos e estudos morfológicos e morfométricos. RESULTADOS: Os animais desnervados estimulados não apresentaram contratura da articulação do tornozelo e não houve automutilações nas patas. Alterações significativas nas áreas das fibras musculares tipo IIB (desnervados estimulados aos 7 dias e tipo IIA e híbridas (desnervados estimulados 28 e 56 dias indicaram menor atrofia. Transição do tipos de fibras musculares foi significativa, indicando uma manutenção do padrão funcional do músculo tibial anterior nos períodos de 7 e 14 dias. CONCLUSÃO: Conclui-se que houve manutenção temporária da estrutura e função do músculo tibial anterior desnervado através da eletroestimulação seletiva.OBJECTIVE: Electrical stimulation for treatment of denervated muscles should be implemented by selective treatment. This study evaluated the effect of selective electrical stimulation on the structure and function of denervated muscle. METHODS: Fifty Wistar mice were allocated to control, stimulated denervated and non-stimulated denervated groups. Following an electrodiagnostic evaluation, the animals underwent complete unilateral denervation of the proximal anterior tibialis muscle. Weekly re

  1. Electrical installations technology

    CERN Document Server

    Whitfield, J F

    1968-01-01

    Electrical Installations Technology covers the syllabus of the City and Guilds of London Institute course No. 51, the "Electricians B Certificate”. This book is composed of 15 chapters that deal with basic electrical science and electrical installations. The introductory chapters discuss the fundamentals and basic electrical principles, including the concept of mechanics, heat, magnetic fields, electric currents, power, and energy. These chapters also explore the atomic theory of electric current and the electric circuit, conductors, and insulators. The subsequent chapter focuses on the chemis

  2. Effect of gait triggered functional electrical stimulation on foot drop patients after stroke%步态诱发功能性电刺激对脑卒中足下垂患者的疗效观察

    Institute of Scientific and Technical Information of China (English)

    刘翠华; 张盘德; 容小川; 周惠嫦; 陈丽珊; 林楚克; 李桂恩; 武士龙

    2011-01-01

    , XFT-2001P neuromuscular locator was used to find sensitive position, then the negative electrode was placed on sensitive position (common peroneal nerve) and the positive electrode was placed on the suitable position (tibialis anterior muscle). Walking function was evaluated before treatment, 1 week after treatment and 2 weeks after treatment.Result: After 2 weeks treatment, daring walking with low-frequency electrical pulse stimulator walking speed, transfer ability, up and down stairs ability improved immediately and the physiological cost consumption of foot drop patients after stroke reduced(P<0.05-0.001). Conclusion: Low-frequency electrical pulse stimulator could improve walking function of affected low limbs offoot drop patients after stroke. Walking speed, transfer ability, up and down stairs ability improved significantly and physiological consumption reduced significantly during walking with the stimulator. The stimulator had no ob-viaus side effect and it was considered to be a safe and effective training equipment.

  3. Electric circuit theory applied electricity and electronics

    CERN Document Server

    Yorke, R

    1981-01-01

    Electric Circuit Theory provides a concise coverage of the framework of electrical engineering. Comprised of six chapters, this book emphasizes the physical process of electrical engineering rather than abstract mathematics. Chapter 1 deals with files, circuits, and parameters, while Chapter 2 covers the natural and forced response of simple circuit. Chapter 3 talks about the sinusoidal steady state, and Chapter 4 discusses the circuit analysis. The fifth chapter tackles frequency response of networks, and the last chapter covers polyphase systems. This book will be of great help to electrical

  4. Electricity market 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-01

    The electricity markets in the Nordic countries have undergone major changes since the electricity market reform work was started in the early 1990s. Sweden, Norway and Finland have had a common electricity market since 1996. The work of also reforming the Danish electricity market was begun in the year 2000. The objective of the electricity market reform is to introduce increased competition, to give the consumers greater freedom of choice and also, by open and expanded trade in electricity, create the conditions for efficient pricing. The Swedish National Energy Administration is the supervisory authority as specified in the Electricity Act, and one of the tasks entrusted to it by the Government is to follow developments on the electricity market and to regularly compile and report current market information. The purpose of the 'Electricity market 2001' publication is to meet the need for generalized and readily accessible information on the conditions on the Nordic market. Iceland is not included in the description. The publication also includes summaries of information from recent years concerning electricity generation and utilization in the Nordic countries, the structure of the electricity market from the players' perspective, trade in electricity in the Nordic countries and in Northern Europe, electricity prices in the Nordic and other countries, and the impact of the electricity sector on the environment. The publication contains data on electricity generation and use during the past years, structure of the electricity market, trade in electricity in the Nordic countries and northern Europe, electricity prices in the Nordic countries and other countries as well as impact of electricity generation system on the environment.

  5. Topics on electricity trade

    Energy Technology Data Exchange (ETDEWEB)

    Skytte, K.

    2001-07-01

    being unable to fulfil the commitments made on the spot market. The disclosed cost of using the regulating power market is a quadratic function of the amount of regulation. This asymmetric cost may encourage bidders with fluctuating production to be more strategic in their way of bidding on the spot market. By using such strategies the extra costs (for e.g. wind power) needed to counter unpredictable fluctuations may be limited. The fourth paper applies the findings in the previous paper to show how a supplier with a 'controllable' production will make strategic bids on the power exchange - in this case a heat pump. The fifth paper discusses the design of the regulating power market and what the choice of design means for suppliers with fluctuating production, e.g. wind turbines. It is found that not only does the accuracy of the wind prediction influence the use of the power exchange, but the structure of the power exchange itself may also play an important role. Several studies of the northern European electricity liberalisation have concluded that developments of a liberalised electricity market and cross border trade can be of benefit for the consumers and bring along a global environmental improvement. All these studies have assumed that a perfect competitive electricity market can be obtained. A number of imperfections, which inevitably will arise, have not been taken into account, - at least in the transition period. These imperfections can be technical, economic or tradition-bound, but may have political characteristics as well. The sixth paper in this thesis surveys those market imperfections which are most likely to appear. Market imperfections can, for example, have structural or political characteristics that imply non-optimal competitive behaviour, e.g., the means to achieve political goals may hinder the desirable effects of the liberalisation. This can, for example, come from the creation of suitable arrangements for survival and enlargement of

  6. Point Electric Stimulation and Children's Amblyopia

    Institute of Scientific and Technical Information of China (English)

    YAN Xing-ke; CHU Hui-ju; WANG Fu-chun; YANG Bo; GAO Yang; HAN Chou-ping

    2007-01-01

    To observe the therapeutic efficacy of electric stimulation on points for children's amblyopia.Method:Ninety children amblyopia cases with ametropia upon correction were randomized into three groups:point electric stimulation,comprehensive conventional therapy and integrative therapy of the above two.And then visual function changes of kids in the three groups were observed.Results:Among the above three therapies,the recovery rates of point electric stimulation,comprehensive conventional therapy and integrative therapy of the two were 83.9%,82.6%and 94.25 respectively,showing no significant difierence(P>0.05) among the three groups.Conclusion:Point electric stimulation has similar action with comprehensive conventional therapy in the treatment of children's amblyopia,and the combination of the two therapies has better effect,indicating point electric stimulation can speed up recovery of visual function of kids with amblyopia.

  7. Research of Brain-Controlled Wheelchair Obstacle Avoidance System Based on Ultrasonic Sensor%基于超声波传感器的脑控轮椅避障系统的研究

    Institute of Scientific and Technical Information of China (English)

    刘甜; 李远清; 王洪涛; 胡友盼

    2012-01-01

    A method of obstacle avoidance is proposed aimed at the phenomenon of collision accident likely caused by the non-stationary nature of the electroencephalogram (EEG) signals while the users steer the brain-controlled wheelchair. Multi-channel ultrasonic sensors obstacle avoidance system and a feedback interface used for obstacle avoidance alert are also designed. The prompt messages displayed on the feedback interface will assist the users to make effective obstacle avoidance decisions. If the wheelchair can't avoid obstacle successfully when the users apply their EEG signals to steer the wheelchair autonomously, the system will send messages to stop the wheelchair immediately to avoid collision with obstacles, which ensures the personal safety of the wheelchair users. The experimental results of brain - controlled wheelchair show that when the safety area critical value and the emergency stop distance critical value of the front and back are respectively set as 500 millimeters, 400 millimeters and 200 millimeters, the obstacle avoidance system with good stability and strong real -time property can meet the needs of brain -controlled wheelchair users' safety navigation.%针对脑控轮椅行驶时因用户脑电信号的不稳定性可能引起碰撞事故发生的现象,提出了一种避障方法,并设计了多路超声波传感器避障系统及避障提示反馈界面;反馈界面上实时显示的提示信息将辅助用户做出有效的避障决策;当用户采用脑电自主控制轮椅运行时,若无法成功避障,则该避障系统立即启动紧急停车功能以避免与障碍物发生碰撞,保证了脑控轮椅用户的人身安全;实验结果表明:当把安全区域临界值、前后及左右紧急停车距离临界值分别设置为500mm、400mm和200mm时,该超声波传感器避障系统稳定性好、实时性强,能够满足脑控轮椅的用户安全导航的需要.

  8. The Nordic financial electricity market

    Energy Technology Data Exchange (ETDEWEB)

    2010-11-15

    NordREG is a cooperation of the Nordic energy regulators. The mission is to actively promote legal and institutional framework and conditions necessary for developing the Nordic and European electricity markets. The financial market is an important market for market participants to mitigate their risks. By providing tools for risk management, the financial market contributes to the efficient functioning of both wholesale and end-user markets. NordREG decided during 2009 to undertake a study on the Nordic financial electricity market. The aim of the report is to consider whether any improvements can be made to further increase the efficiency of the Nordic financial electricity market in order to secure an optimal price setting in the wholesale and the end-user markets

  9. Electrical breakdown in tissue electroporation.

    Science.gov (United States)

    Guenther, Enric; Klein, Nina; Mikus, Paul; Stehling, Michael K; Rubinsky, Boris

    2015-11-27

    Electroporation, the permeabilization of the cell membrane by brief, high electric fields, has become an important technology in medicine for diverse application ranging from gene transfection to tissue ablation. There is ample anecdotal evidence that the clinical application of electroporation is often associated with loud sounds and extremely high currents that exceed the devices design limit after which the devices cease to function. The goal of this paper is to elucidate and quantify the biophysical and biochemical basis for this phenomenon. Using an experimental design that includes clinical data, a tissue phantom, sound, optical, ultrasound and MRI measurements, we show that the phenomenon is caused by electrical breakdown across ionized electrolysis produced gases near the electrodes. The breakdown occurs primarily near the cathode. Electrical breakdown during electroporation is a biophysical phenomenon of substantial importance to the outcome of clinical applications. It was ignored, until now.

  10. Effect of fastigial nucleus electric stimulation on executive function of patients with cerebral infarction%小脑顶核电刺激对脑梗死患者脑执行功能的影响

    Institute of Scientific and Technical Information of China (English)

    隆昱洲; 雷进; 罗丽华; 刘姚; 尚正良

    2012-01-01

    目的 探讨小脑顶核电刺激对脑梗死患者治疗前后脑执行功能的影响.方法 脑梗死患者270例,随机分成治疗组和对照组,各135例,均接受常规药物治疗,治疗组在此基础上加用小脑顶核电刺激,于治疗前和治疗后2周、3个月进行威斯康星卡片分类测验(WCST)、Strop色词测验、连线测验、词语流畅性测验.结果 治疗后2周,治疗组和对照组WCST分类次数、错误数、持续性错误数、非持续性错误数及Stroop色词测验的耗时数、正确数和连线测验A、语词流畅性均较治疗前有改善(P均<0.05);治疗后3个月,对照组在WCST分类次数、持续性错误数和Stroop色词测验的耗时数、正确数及连线测验、词语流畅性测验较治疗后2周下降(P均<0.01),治疗组在WCST持续性错误数、非持续性错误数和Stroop色词测验的耗时数、连线测验A较2周末时有改善(P均<0.05),其他测验无明显改善(P>0.05).结论 电刺激小脑顶核能改善脑梗死患者的脑执行功能.%Objective To investigate the effect of fastigial nucleus electric stimulation on executive function of patients with cerebral infarction. Methods A total of 270 patients with cerebral infarction were divided into treatment group and control group, with 135 cases in each, and treated with routine treatment. The treatment group was given fastigial nucleus electric stimulation. All patients were evaluated with Wisconsin card sorting test( WCST) , Stroop color word test (SCWT) , trail making test A, verbal fluency test before treatments and 2 weeks,3 months after treatments. Results At 2 weeks after treatment, WCST grade, SCWT, trail making test A, verbal fluency test of treatment groups and control group were significantly improved compared with beginning of treatment ( all P 0.05). Conclusion Executive function of patients with cerebral infarction can be increased by treatment of electric stimulaion on cerebellar fastigial nucleus.

  11. Seismic reliability assessment of electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, A. [Stanford Univ., CA (United States); Bouabid, J. [Risk Management Solutions, Menlo Park, CA (United States)

    1995-12-31

    This paper presents a methodology for the seismic risk assessment of electric power systems. In evaluating damage and loss of functionality to the electric power components, fragility curves and restoration functions are used. These vulnerability parameters are extracted from the GIS-based regional loss estimation methodology being developed for the US. Observed damage in electric power components during the Northridge earthquake is used to benchmark the methodology. The damage predicted using these vulnerability parameters is found to be in good agreement with the damage observed during the earthquake.

  12. Electric and magnetic dipole shielding constants for the ground state of the relativistic hydrogen-like atom: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Stefańska, Patrycja

    2011-01-01

    The Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30 (1997) 825; erratum 30 (1997) 2747] is exploited to derive closed-form expressions for electric ($\\sigma_{\\mathrm{E}}$) and magnetic ($\\sigma_{\\mathrm{M}}$) dipole shielding constants for the ground state of the relativistic hydrogen-like atom with a point-like and spinless nucleus of charge $Ze$. It is found that $\\sigma_{\\mathrm{E}}=Z^{-1}$ (as it should be) and $$\\sigma_{\\mathrm{M}}=-(2Z\\alpha^{2}/27)(4\\gamma_{1}^{3}+6\\gamma_{1}^{2}-7\\gamma_{1}-12) /[\\gamma_{1}(\\gamma_{1}+1)(2\\gamma_{1}-1)],$$ where $\\gamma_{1}=\\sqrt{1-(Z\\alpha)^{2}}$ ($\\alpha$ is the fine-structure constant). This expression for $\\sigma_{\\mathrm{M}}$ agrees with earlier findings of several other authors, obtained with the use of other analytical techniques, and is elementary compared to an alternative one presented recently by Cheng \\emph{et al.} [J. Chem. Phys. 130 (2009) 144102], which involves an infinite series of ratios of the Euler'...

  13. An investigation of hydrogen-bonding effects on the nitrogen and hydrogen electric field gradient and chemical shielding tensors in the 9-methyladenine real crystalline structure: a density functional theory study.

    Science.gov (United States)

    Mirzaei, Mahmoud; Hadipour, Nasser L

    2006-04-13

    Hydrogen-bonding effects in the real crystalline structure of 9-methyladenine, 9-MA, were studied using calculated electric field gradient, EFG, and chemical shielding, CS, tensors for nitrogen and hydrogen nuclei via density functional theory. The calculations were carried out at the B3LYP and B3PW91 levels with the 6-311++G basis set via the Gaussian 98 package. Nuclear quadrupole coupling constants, C(Q), and asymmetry parameters, eta(Q), are reported for (14)N and (2)H. The chemical shielding anisotropy, Deltasigma, and chemical shielding isotropy, sigma(iso), are also reported for (15)N and (1)H. The difference between the calculated parameters of the monomer and heptameric layer-like cluster 9-MA shows how much H-bonding interactions affect the EFG and CS tensors of each nucleus. This result indicates that N(10) (imino nitrogen) has a major role in H-bonding interactions, whereas that of N(9) is negligible. There is good agreement between the present calculated parameters and reported experimental data. Although some discrepancies were observed, this could be attributed to the different conditions which were applied for calculation and the experiments.

  14. Non-invasive neuromuscular electrical stimulation in patients with central nervous system lesions: an educational review.

    Science.gov (United States)

    Schuhfried, Othmar; Crevenna, Richard; Fialka-Moser, Veronika; Paternostro-Sluga, Tatjana

    2012-02-01

    The aim of this educational review is to provide an overview of the clinical application of transcutaneous electrical stimulation of the extremities in patients with upper motor neurone lesions. In general two methods of electrical stimulation can be distinguished: (i) therapeutic electrical stimulation, and (ii) functional electrical stimulation. Therapeutic electrical stimulation improves neuromuscular functional condition by strengthening muscles, increasing motor control, reducing spasticity, decreasing pain and increasing range of motion. Transcutaneous electrical stimulation may be used for neuromuscular electrical stimulation inducing repetitive muscle contraction, electromyography-triggered neuromuscular electrical stimulation, position-triggered electrical stimulation and subsensory or sensory transcutaneous electric stimulation. Functional electrical stimulation provokes muscle contraction and thereby produces a functionally useful movement during stimulation. In patients with spinal cord injuries or stroke, electrical upper limb neuroprostheses are applied to enhance upper limb and hand function, and electrical lower limb neuroprostheses are applied for restoration of standing and walking. For example, a dropped foot stimulator is used to trigger ankle dorsiflexion to restore gait function. A review of the literature and clinical experience of the use of therapeutic electrical stimulation as well as of functional electrical stimulation in combination with botulinum toxin, exercise therapy and/or splinting are presented. Although the evidence is limited we conclude that neuromuscular electrical stimulation in patients with central nervous system lesions can be an effective modality to improve function, and that combination with other treatments has an additive therapeutic effect.

  15. Hemichannel composition and electrical synaptic transmission: molecular diversity and its implications for electrical rectification.

    Science.gov (United States)

    Palacios-Prado, Nicolás; Huetteroth, Wolf; Pereda, Alberto E

    2014-01-01

    Unapposed hemichannels (HCs) formed by hexamers of gap junction proteins are now known to be involved in various cellular processes under both physiological and pathological conditions. On the other hand, less is known regarding how differences in the molecular composition of HCs impact electrical synaptic transmission between neurons when they form intercellular heterotypic gap junctions (GJs). Here we review data indicating that molecular differences between apposed HCs at electrical synapses are generally associated with rectification of electrical transmission. Furthermore, this association has been observed at both innexin and connexin (Cx) based electrical synapses. We discuss the possible molecular mechanisms underlying electrical rectification, as well as the potential contribution of intracellular soluble factors to this phenomenon. We conclude that asymmetries in molecular composition and sensitivity to cellular factors of each contributing hemichannel can profoundly influence the transmission of electrical signals, endowing electrical synapses with more complex functional properties.

  16. Agent和供给函数均衡模型在电力市场竞价中的应用及对比分析%Application and Comparison of Agent and Supply Function Equilibrium Models in Electricity Market Auction

    Institute of Scientific and Technical Information of China (English)

    曾鸣; 王玉萍; 王蕾; 薛松; 何彦英

    2014-01-01

    在考虑期货市场和日常市场极值的基础上构建 agent模型和供给函数均衡( supply function equilibrium ,SFE)模型,并针对模型的预测准确程度进行对比分析。以某城市电网中的4个典型工作日为例进行算例分析,结果表明在非用电高峰时段,agent模型对于价格水平和波动性的预测能力较强,而SFE模型可以更准确地预测非高峰时段的电价。%The advancement in power system reform promotes an increasingly competitive electricity mar-ket .Under such an environment , based on competitors and personal situation ,power generation companies have developed reasonable and effective bidding strategies to maximize profits .By considering extreme val-ue of the future market and the daily market , an agent model and supply function equilibrium ( SFE) mod-el are built .Then, the prediction accuracy obtained by the models is compared .With a numerical example of four typical days in a regional grid of some cities , it is shown that , in the non-peak hours , the agent model has a strong forecasting ability of the price level and volatility , while the SFE model can more accu-rately predict off-peak price level .

  17. Electrical conductivity of chondritic meteorites

    Science.gov (United States)

    Duba, AL; Didwall, E. M.; Burke, G. J.; Sonett, C. P.

    1987-01-01

    The electrical conductivity of samples of the Murchison and Allende carbonaceous chondrites is 4 to 6 orders of magnitude greater than rock forming minerals such as olivine for temperatures up to 700 C. The remarkably high electrical conductivity of these meteorites is attributed to carbon at the grain boundaries. Much of this carbon is produced by pyrolyzation of hydrocarbons at temperatures in excess of 150 C. As the temperature increases, light hydrocarbons are driven off and a carbon-rich residue or char migrates to the grain boundaries enhancing electrical conductivity. Assuming that carbon was present at the grain boundaries in the material which comprised the meteorite parent bodies, the electrical heating of such bodies was calculated as a function of body size and solar distance during a hypothetical T-Tauri phase of the sun. Input conductivity data for the meteorite parent body were the present carbonaceous chondrite values for temperatures up to 840 C and the electrical conductivity values for olivine above 840 C.

  18. Electrical installation calculations advanced

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for advanced electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practiceA step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3For apprentices and electrical installatio

  19. Electrical machines diagnosis

    CERN Document Server

    Trigeassou, Jean-Claude

    2013-01-01

    Monitoring and diagnosis of electrical machine faults is a scientific and economic issue which is motivated by objectives for reliability and serviceability in electrical drives.This book provides a survey of the techniques used to detect the faults occurring in electrical drives: electrical, thermal and mechanical faults of the electrical machine, faults of the static converter and faults of the energy storage unit.Diagnosis of faults occurring in electrical drives is an essential part of a global monitoring system used to improve reliability and serviceability. This diagnosis is perf

  20. Curative effect observation of electrical stimulation to cerebellar fastigial nucleus on nerve function recovery of cerebral infarction patients%电刺激小脑顶核对脑梗死患者神经功能恢复的疗效观察

    Institute of Scientific and Technical Information of China (English)

    彭昌鼎; 孙鸣; 王昌铭; 吉国泰; 姬向丽

    2002-01-01

    Objective To observe curative effect of electrical stimulation cerebellar fastigial nucleus on nerve function recovery of cerebral infarction patients.Method The patients were treated with electrical stimulation cerebellar fastigial nucleus except for routine drugs,the electrode were placed on the bilateral mastoid processes,giving pulse electric current for forty minutes two times per day,for a 10 day couse treatment.The parameter was set at model 1,frequency was 131% ~ 136% and intensity was 70% ~ 90% .Result Total effective rate of therapeutic group and control group were 91.7% and 71.4% separately.χ 2=4.860(P< 0.05).The nerver function defect score was manifestly decreased.There was a significant difference between the therapeutic group and control group,and between before and after treatment in therapeutic group(P< 0.01).Conclusion The experiment suggested that the treatment of cerebral infarction by drugs except adding electrical stimulation of cerebellar fastigial nucleus is better than by drugs along.The electrical stimulation of cerebellar fastigial nucleus has obvious protective effect.It can promote recovery of cerebral infarction.

  1. Electricity market 2000

    Energy Technology Data Exchange (ETDEWEB)

    Korsfeldt, T.; Petsala, B.

    2000-08-01

    The electricity markets in the Nordic countries have undergone major changes since the electricity market reform work was started in the early 1990s. Sweden, Norway and Finland have a common electricity market since 1996.The work of also reforming the Danish electricity market was begun in the year 2000. The objective of the electricity market reform is to introduce increased competition,to give the consumers greater freedom of choice and also, by open and expanded trade in electricity, create the conditions for efficient pricing. The Swedish National Energy Administration is the supervisory authority as specified in the Electricity Act, and one of the tasks entrusted to it by the Government is to follow developments on the electricity market and to regularly compile and report current market information. The purpose of the present publication is to meet the need for generalized and readily accessible information on the conditions on the Nordic markets.The publication includes summaries of information from recent years concerning electricity generation and utilization in the Nordic countries, the structure of the electricity market from the players' perspective trade in electricity in the Nordic countries and in Northern Europe, electricity prices in the Nordic and other countries, and the impact of the electricity sector on the environment.

  2. 电刺激阴茎海绵体神经测定大鼠勃起功能的方法探讨%Measuring erectile function in rats through electrical stimulation of the cavernous nerve

    Institute of Scientific and Technical Information of China (English)

    王先进; 沈周俊; 张敏光; 钟山; 张存明; 朱照伟

    2012-01-01

    目的:探讨电刺激阴茎海绵体神经(CN)测定大鼠勃起功能的方法.方法:选择4月龄雄性SD大鼠20只,体质量(425±25)g.左颈总动脉内插管,直接法持续监测大鼠平均动脉压(MAP);左侧海绵体内插管测定阴茎海绵体内压(ICP);前列腺右侧叶前外侧表面暴露右侧CN,通过电刺激CN诱发阴茎勃起.电刺激参数为:5V,2 ms,25 Hz,每次刺激持续1 min,间隔5 min重复电刺激,共刺激3次.电刺激CN前的(ICP/MAP)×100(rR)代表阴茎海绵体的静息状态;电刺激CN后的(ICP最大值/MAP)×100(bR)代表阴茎海绵体的勃起状态或大鼠的基础勃起功能;bR/rR代表阴茎勃起后ICP的增高程度.结果:电刺激CN使ICP明显升高,MAP变化不大,表明电刺激可有效诱发勃起.ICP、MAP、rR、bR、bR/rR等各项指标3次重复测定之间的差异均无统计学意义(均P>0.05),表明电刺激法结果稳定.rR、bR和bR/rR总的平均值分别为(12.00±2.62)%、(67.68±11.28)%和(5.85±1.80).结论:电刺激阴茎CN测定大鼠勃起功能的方法稳定易重复,能够客观准确地评估阴茎的勃起程度,是研究阴茎勃起功能的重要技术,值得在国内推广.%Objective:To investigate the feasibility of measuring erectile function in rats through the electrical stimulation of the cavernous nerve(CN).Methods: Twenty 4-month-old male SD rats( weight,425 ± 25 g) were used in our study.The erectile response was expressed as a ratio of intracavernous pressure(ICP)and mean arterial pressure(MAP) ,(ICP/MAP) × 100,during electrostimulation of the right CN.The electrical-stimulation parameters were 5 V,2 ms,25 Hz,and 1 min for each stimulation and once again every 5 minutes.Before electrostimulation,the(ICP/MAP) ×100 (abbr,rR) represents resting state of penis.After electrostimulation,the(ICPmax/ MAP) × l00(abbr,bR)represents fundamentally erectile state of penis.bR/rR stands for the increased degree of ICP induced by electrostimulation

  3. Identification of potential locations of electric vehicle supply equipment

    Science.gov (United States)

    Brooker, R. Paul; Qin, Nan

    2015-12-01

    Proper placement of electric vehicle supply equipment (charging stations) requires an understanding of vehicle usage patterns. Using data from the National Household Travel Survey on vehicle mileage and destination patterns, analyses were performed to determine electric vehicles' charging needs, as a function of battery size and state of charge. This paper compares electric vehicle charging needs with Department of Energy electric vehicle charging data from real-world charging infrastructure. By combining the electric vehicles charging needs with charging data from real-world applications, locations with high electric vehicle charging likelihood are identified.

  4. Home Electrical Safety Checklist

    Science.gov (United States)

    ... in kitchens, bathrooms, and other areas where the risk of electric shock is higher. Consider having GFCIs installed in ... life. By installing GFCIs, you are reducing your risk of electric shock. AFCIs are special circuit breakers that detect ...

  5. Electricity and Man (Rev.)

    Energy Technology Data Exchange (ETDEWEB)

    Asimov, Isaac

    1974-01-01

    Our whole industrial civilization depends upon cheap energy streaking out in all directions and under fingertip controls—and that would be very difficult without electric current. It would take enormous ingenuity to find substitutes. If all electricity were shut off, then all electronic devices would be dead. Electric lights would darken. Aluminum would become a rare metal. All factories would have to develop power sources on the spot and would have to switch to primitive, mechanical controls. Every house and every farm would have to give up items we have come to take for granted—not only electric lights, but electric irons, electric toasters, electric water pumps, electric control of furnaces, and so on.

  6. Mimicking muscle activity with electrical stimulation

    Science.gov (United States)

    Johnson, Lise A.; Fuglevand, Andrew J.

    2011-02-01

    Functional electrical stimulation is a rehabilitation technology that can restore some degree of motor function in individuals who have sustained a spinal cord injury or stroke. One way to identify the spatio-temporal patterns of muscle stimulation needed to elicit complex upper limb movements is to use electromyographic (EMG) activity recorded from able-bodied subjects as a template for electrical stimulation. However, this requires a transfer function to convert the recorded (or predicted) EMG signals into an appropriate pattern of electrical stimulation. Here we develop a generalized transfer function that maps EMG activity into a stimulation pattern that modulates muscle output by varying both the pulse frequency and the pulse amplitude. We show that the stimulation patterns produced by this transfer function mimic the active state measured by EMG insofar as they reproduce with good fidelity the complex patterns of joint torque and joint displacement.

  7. Electric Vehicle Propulsion System

    OpenAIRE

    2014-01-01

    Electric vehicles are being considered as one of the pillar of eco-friendly solutions to overcome the problem of global pollution and radiations due to greenhouse gases. Present thesis work reports the improvement in overall performance of the propulsion system of an electric vehicle by improving autonomy and torque-speed characteristic. Electric vehicle propulsion system consists of supply and traction system, and are coordinated by the monitoring & control system. Case of light electric veh...

  8. Electric Field Imaging Project

    Science.gov (United States)

    Wilcutt, Terrence; Hughitt, Brian; Burke, Eric; Generazio, Edward

    2016-01-01

    NDE historically has focused technology development in propagating wave phenomena with little attention to the field of electrostatics and emanating electric fields. This work is intended to bring electrostatic imaging to the forefront of new inspection technologies, and new technologies in general. The specific goals are to specify the electric potential and electric field including the electric field spatial components emanating from, to, and throughout volumes containing objects or in free space.

  9. Blink restoration by the functional electrical stimulation in unilateral facial nerve palsy rabbits%功能性电刺激恢复周围性面神经麻痹兔眨眼功能的研究

    Institute of Scientific and Technical Information of China (English)

    薛玉斌; 冯国栋; 丁秀勇; 赵杨; 崔婷婷; 高志强

    2014-01-01

    兔的双侧同步眨眼.%Objective Tocompare the effects of different waveforms and parameters of electrical stimulation to elicit a blink,and construct a functional electrical stimulation (FES) system to restore synchronous blink in unilateral facial nerve palsy (FNP).Methods Firstly,twenty-four rabbits were surgically induced unilateral FNP and were divided into three groups,who received square,sine and triangle pulse wareforms,respectirely.Both the healthy and the paralysis eyelids of the rabbits received pulse train stimulation to produce a blink in both eyes.For each rabbit,twenty-seven combinations of frequencies (25 Hz,50 Hz and 100 Hz) and nine pulse widths (1-9 ms) were stimulated.The threshold amplitude and electric charge to elicit a blink was compared between different waveforms and different parameters.Secondly,a FES system was constructed to treat six surgically induced unilateral FNP rabbit chosen in the twenty-four rabbits,it consisted by an electromyogram (EMG) amplifier module which record the EMG of the healthy muscle,and a stimulator which received the EMG input and output a pulse train stimulation when triggered by the EMG.Results When the carrier frequency of the pulse train was 25 Hz,it was not able to induce a smooth blink.However,when the carrier frequencies were 50 Hz and 100 Hz,a smooth blink could be induced.The voltage required by 100 Hz was lower than 50 Hz,but it cost more electric charge.The amplitude that square waveforms required was far lower than sine and triangle,but the electric charge between the three waveforms was similar.Synchronous blink could be restored in the six unilateral FNP rabbits with the FES system.Conclusions To elicit a blink,square pulse train delivered in 50 Hz is a preferable option.The motion of the healthy eyelids as a source of information for stimulation of the paralyzed sides can restore the synchronous blink in unilateral FNP rabbits.

  10. Schneider Electric sozdajot set

    Index Scriptorium Estoniae

    2003-01-01

    Maailma juhtiv elektriseadmete müüja Schneider Electric ühendab oma ettevõtted Balti- ja Põhjamaades uude divisjoni, mille nimeks saab Schneider Nordic Baltic. Eestis luuakse AS Schneider Electric Eesti, mis seni tegutses AS-i Lexel Electric nime all

  11. Electricity Serves Our Community.

    Science.gov (United States)

    Rakow, Steven J., Ed.

    1992-01-01

    Features a color poster entitled "Electricity Serves Our Community" and describes how the poster can be used to help teach about energy, electricity concepts, and types of electrical generation. Explains how teachers can obtain other resources such as posters, lesson plans, and kits from the National Energy Foundation. (PR)

  12. Electric Current Solves Mazes

    Science.gov (United States)

    Ayrinhac, Simon

    2014-01-01

    We present in this work a demonstration of the maze-solving problem with electricity. Electric current flowing in a maze as a printed circuit produces Joule heating and the right way is instantaneously revealed with infrared thermal imaging. The basic properties of electric current can be discussed in this context, with this challenging question:…

  13. Electric field analysis

    CERN Document Server

    Chakravorti, Sivaji

    2015-01-01

    This book prepares newcomers to dive into the realm of electric field analysis. The book details why one should perform electric field analysis and what are its practical implications. It emphasizes both the fundamentals and modern computational methods of electric machines. The book covers practical applications of the numerical methods in high voltage equipment, including transmission lines, power transformers, cables, and gas insulated systems.

  14. Electrical Power Converter

    NARCIS (Netherlands)

    Ferreira, J.A.

    2014-01-01

    Electrical power converter for converting electrical power of a power source connected or connectable at an input to electrical DC-power at an output, wherein between the input and the output a first circuit of submodules is provided, wherein said first circuit of submodules and the power source for

  15. Institutionalising Green Electricity

    NARCIS (Netherlands)

    Hofman, P.

    2004-01-01

    Both energy companies and consumers have embraced green electricity as a concept in which electricity produced by renewable energy sources is separately marketed and priced from conventionally generated electricity based on fossil or nuclear sources. After its introduction in 1995 by an energy distr

  16. Future Electricity Markets

    DEFF Research Database (Denmark)

    Pinson, Pierre

    2015-01-01

    The changing face of energy production in Europe necessitates a rethink in the way that electricity markets are structured. The ‘5s’ (Future Electricity Markets) project is a multi-disciplinary project that is looking to challenge the current approach to the design and operation of electricity...

  17. Fundamentals of electrical drives

    CERN Document Server

    Veltman, André; De Doncker, Rik W

    2007-01-01

    Provides a comprehensive introduction to various aspects of electrical drive systems. This volume provides a presentation of dynamic generic models that cover all major electrical machine types and modulation/control components of a drive as well as dynamic and steady state analysis of transformers and electrical machines.

  18. The Electric Vehicle Development

    DEFF Research Database (Denmark)

    Wang, Jingyu; Yingqi, Liu; Kokko, Ari

    2014-01-01

    in three aspects-city environment, government and stakeholders. Then the paper discusses the promotion ways and role of government and consumer. Finally, the paper offers some suggestions to promote electric vehicles in China: focusing on feasibility and adaptability of electric vehicles, playing...... government`s leading role, improving low-awareness and acceptance of electric vehicles and focusing on user requirements....

  19. Electric glass capturing markets

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, K.; Wikstroem, T.

    1996-11-01

    Electric glass has found its place on the construction market. In public buildings, electrically heatable windows are becoming the leading option for large glass walls. Studies on detached houses, both new and renovated, show that floor heating combined with electrically heatable windowpanes is the best choice with respect to resident`s comfort. (orig.)

  20. Electric Vehicle Technician

    Science.gov (United States)

    Moore, Pam

    2011-01-01

    With President Obama's goal to have one million electric vehicles (EV) on the road by 2015, the electric vehicle technician should have a promising and busy future. "The job force in the car industry is ramping up for a revitalized green car industry," according to Greencareersguide.com. An electric vehicle technician will safely troubleshoot and…

  1. STUNNING : Electrical Stunning

    NARCIS (Netherlands)

    Lambooij, B.

    2014-01-01

    Electrical stunning is used all over the world to render animals, including poultry, unconscious before slaughter that lasts until exsanguination results in death. The basic physiological principle of electrical stunning is to administer sufficient electric current through the head of an animal so t

  2. Effect of gait triggered functional electrical stimulation on incomplete spinal cord injury patients%步态诱发功能性电刺激对不完全性脊髓损伤患者的疗效观察

    Institute of Scientific and Technical Information of China (English)

    谢映; 朱文新; 李玲; 吴汨霞; 张鹏程; 李洋

    2013-01-01

    Objective: To observe the effect of gait triggered functional electrical stimulation on incomplete spinal cord in-jury(SCI). Method: Forty patients with incomplete SCI after fractures of thoracolumbar segment were randomly divided into two groups: the treatment group(20cases) and the control group (20cases). Based on routine medical treatment and rehabilitation therapy, patients of treatment group received functional electrical stimulation(FES) on common perone-al nerve and tibia]is anterior muscle of affected side by using XFT-2001 10w-frequency electrical pulse stimulator, and at the same time 15-20min walking training, twice a day, 5-6d per week,4 weeks in total. Scores of FIM,10m maximum walking speed and tibialis anterior muscle motor evoked potential(MED) latency were evaluated before treatment, 2 weeks after treatment and 4 weeks after treatment. Tibialis anterior muscular strength was compared before treatment and 4 weeks after treatment. Result: After 2 weeks treatment, scores of FIM, 10m maximum walking speed and tibialis anterior muscle MEP latency in both groups had not significant difference (P> 0.05) 0 After 4 weeks treatment, It was shown that the scores of FIM and 10m maximum walking speed increased after treatment(P<0.01, P<0.05), tibialis anterior muscle latency shortened (P<0.01), tibialis anterior muscular strength enhanced (P<0.05) compared with control group. Conclusion: FES could improve walking function of incomplete SCI patient. MEP examination could provide objective and quantitative basis for judging the motor functional status of spinal cord. FES was considered to be a safe and effective training method.%目的:观察步态诱发功能性电刺激治疗不完全性脊髓损伤患者的疗效.方法:对40例不完全性脊髓损伤的患者,随机分为两组,对照组进行常规药物治疗、康复治疗,治疗组除常规药物治疗、康复治疗,每天佩戴步态诱发功能性电刺激进行患侧腓总神经、胫前

  3. Polymers for electricity and electronics materials, properties, and applications

    CERN Document Server

    Drobny, Jiri George

    2011-01-01

    The comprehensive, practical book that explores the principles, properties, and applications of electrical polymers The electrical properties of polymers present almost limitless possibilities for industrial research and development, and this book provides an in-depth look at these remarkable molecules. In addition to traditional applications in insulating materials, wires, and cables, electrical polymers are increasingly being used in a range of emerging technologies. Presenting a comprehensive overview of how electrical polymers function and how they can be applied in the elec

  4. The Future of Electricity Resource Planning

    Energy Technology Data Exchange (ETDEWEB)

    Kahrl, Fredrich [Energy and Environmental Economics, Inc., San Francisco, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lavin, Luke [Energy and Environmental Economics, Inc., San Francisco, CA (United States); Ryan, Nancy [Energy and Environmental Economics, Inc., San Francisco, CA (United States); Olsen, Arne [Energy and Environmental Economics, Inc., San Francisco, CA (United States); Schwartz, Lisa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-09-14

    Electricity resource planning is the process of identifying longer-term investments to meet electricity reliability requirements and public policy goals at a reasonable cost. Resource planning processes provide a forum for regulators, electric utilities, and electricity industry stakeholders to evaluate the economic, environmental, and social benefits and costs of different investment options. By facilitating a discussion on future goals, challenges and strategies, resource planning processes often play an important role in shaping utility business decisions. Resource planning emerged more than three decades ago in an era of transition, where declining electricity demand and rising costs spurred fundamental changes in electricity industry regulation and structure. Despite significant changes in the industry, resource planning continues to play an important role in supporting investment decision making. Over the next two decades, the electricity industry will again undergo a period of transition, driven by technological change, shifting customer preferences and public policy goals. This transition will bring about a gradual paradigm shift in resource planning, requiring changes in scope, approaches and methods. Even as it changes, resource planning will continue to be a central feature of the electricity industry. Its functions — ensuring the reliability of high voltage (“bulk”) power systems, enabling oversight of regulated utilities and facilitating low-cost compliance with public policy goals — are likely to grow in importance as the electricity industry enters a new period of technological, economic and regulatory change. This report examines the future of electricity resource planning in the context of a changing electricity industry. The report examines emerging issues and evolving practices in five key areas that will shape the future of resource planning: (1) central-scale generation, (2) distributed generation, (3) demand-side resources, (4

  5. Os efeitos da estimulação elétrica funcional na assimetria cortical inter-hemisférica The effects of functional electrical stimulation on cortical interhemispheric asymmetry

    Directory of Open Access Journals (Sweden)

    Letícia Ecard

    2007-09-01

    Full Text Available O objetivo do presente estudo foi avaliar os efeitos da estimulação elétrica funcional na assimetria cortical inter-hemisférica. Para tal, simultaneamente ao registro da atividade eletroencefalográfica, realizou-se eletroestimulação no antebraço direito para estimulação da extensão do indicador. A amostra consistiu de 45 sujeitos randomizados em 3 grupos de 15 sujeitos cada: grupo controle (submetido a 24 blocos de estimulação com intensidade de corrente zero, grupo 1 (24 blocos e grupo 2 (36 blocos. A assimetria entre os pares de eletrodos F3-F4, C3-C4 e P3-P4 foi analisada ao longo dos grupos através de uma Anova. Os resultados apontaram para uma interação grupo x eletrodo e uma tendência de diminuição da assimetria inter-hemisférica após a eletroestimulação.The aim of the present study was to assess the effects of functional electrical stimulation (FES on cortical interhemispheric asymmetry. Electrostimulation was performed on the right forearm to stimulate the extension of the index finger. EEG activity was recorded simultaneously. The sample included 45 subjects randomly divided into 3 groups of 15 subjects each: control group (submitted to 24 blocks of stimulation at a null intensity current, group 1 (24 blocks and group 2 (36 blocks. Interhemispheric asymmetry between F3-F4, C3-C4 and P3-P4 was analyzed through an Anova. Results pointed out to a group x electrode interaction and a general tendency of asymmetry decrease after stimulation.

  6. Alterações na coerência cortical inter-hemisférica produzidas pela estimulação elétrica funcional (FES Changes in cortical interhemispheric coherence produced by functional electrical stimulation (FES

    Directory of Open Access Journals (Sweden)

    Letícia Ecard

    2007-06-01

    Full Text Available O presente estudo teve como objetivo observar alterações corticais produzidas pela estimulação elétrica funcional (FES, através da eletrencefalografia quantitativa (EEGq. Simultaneamente à captação do sinal eletrencefalográfico, realizou-se uma eletroestimulação no antebraço direito para estimulaç��o da extensão do indicador. A amostra consistiu de 45 sujeitos randomizados em 3 grupos de 15. O grupo controle foi submetido a 24 blocos de estimulação com intensidade de corrente zero. O grupo 1 foi submetido a 24 blocos e o grupo 2 a 36 blocos. A coerência entre os pares de eletrodos F3-F4, C3-C4 e P3-P4 foi analisada ao longo dos grupos através de avaliação estatística. Os resultados apontaram para um aumento da coerência inter-hemisférica após a eletroestimulação.The aim of the present study was to observe cortical alterations produced by functional electrical stimulation (FES, through quantitative electroencephalography (qEEG. Electrostimulation was performed on the right forearm to stimulate the extension of the index finger. EEG activity was recorded simultaneously. The sample consisted of 45 subjects randomly divided into 3 groups of 15 subjects each. The control group was submitted to 24 blocks of stimulation at a current intensity of zero. Group 1 was submitted to 24 blocks and group 2 to 36 blocks. Interhemispheric coherence between F3-F4, C3-C4 and P3-P4 was assessed through a statistical analysis. Results pointed out to increased coherence values after stimulation.

  7. Electrical installation calculations basic

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo

  8. Pragmatic electrical engineering fundamentals

    CERN Document Server

    Eccles, William

    2011-01-01

    Pragmatic Electrical Engineering: Fundamentals introduces the fundamentals of the energy-delivery part of electrical systems. It begins with a study of basic electrical circuits and then focuses on electrical power. Three-phase power systems, transformers, induction motors, and magnetics are the major topics.All of the material in the text is illustrated with completely-worked examples to guide the student to a better understanding of the topics. This short lecture book will be of use at any level of engineering, not just electrical. Its goal is to provide the practicing engineer with a practi

  9. Managing electrical safety

    CERN Document Server

    Wiggins, James H, Jr

    2001-01-01

    Managing Electrical Safety provides an overview of electric basics, hazards, and established standards that enables you to understand the hazards you are likely to encounter in your workplace. Focusing on typical industrial environments-which utilize voltages much higher than household or office circuits-the author identifies the eight key components of an electrical safety program and examines each using a model safety management process. You'll learn how to identify electrical hazards, how to prescribe necessary electrical Personal Protective Equipment, how to ensure that equipment is de-ene

  10. Electricity information 2012

    CERN Document Server

    2012-01-01

    Electricity Information provides a comprehensive review of historical and current market trends in the OECD electricity sector, including 2011 preliminary data. An Introduction, notes, definitions and auxiliary information are provided in Part I. Part II of the publication provides an overview of the world electricity developments in 2010 covering world electricity and heat production, input fuel mix, supply and consumption, and electricity imports and exports. A greater focus is given to the 34 OECD countries with more detailed information covering production, installed capacity, input energy

  11. Electric wiring domestic

    CERN Document Server

    Coker, A J

    1992-01-01

    Electric Wiring: Domestic, Tenth Edition, is a clear and reliable guide to the practical aspects of domestic electric wiring. Intended for electrical contractors, installation engineers, wiremen and students, its aim is to provide essential up to date information on modern methods and materials in a simple, clear, and concise manner. The main changes in this edition are those necessary to bring the work into line with the 16th Edition of the Regulations for Electrical Installations issued by the Institution of Electrical Engineers. The book begins by introducing the basic features of domestic

  12. The electricity industry perspective

    Energy Technology Data Exchange (ETDEWEB)

    Orchison, K. [Electricity Supply Association of Australia Ltd., Sydney, NSW (Australia)

    1996-12-31

    A revolution has been sweeping through the electricity supply business in Australia in the past decade and especially in the past five years. Electricity suppliers were early adherents to the pursuit of economic reform, beginning a drive towards greater efficiency in the mid-1980s and accelerating the process as government, pushed in turn by industry and commerce, took up pursuit of competitive energy markets, including radical restructuring of the State-owned utility organizations. The aim of this paper is to provide an overview of the electricity supply business. It include an outline of the major challenges confronting the electricity supply business in Australia, particularly as a result of the introduction of competitive markets in electricity and natural gas. Deregulation will see the providers of electricity and gas reposition themselves as organizations able to supply the total energy needs of customers. A de-regulated electricity market also offers cogeneration plants new opportunities to sell surplus electricity to generators, distribution businesses or directly to customers. The major frontiers facing the electricity supply business in Australia is seen to be that of productively channelling change. How this is handled has substantial implications for those who purchase electricity, suppliers of fuel to electricity generators or rivals in the marketplace. (author).

  13. Electricity as Transportation ``Fuel''

    Science.gov (United States)

    Tamor, Michael

    2013-04-01

    The personal automobile is a surprisingly efficient device, but its place in a sustainable transportation future hinges on its ability use a sustainable fuel. While electricity is widely expected to be such a ``fuel,'' the viability of electric vehicles rests on the validity of three assumptions. First, that the emissions from generation will be significantly lower than those from competing chemical fuels whether `renewable' or fossil. Second, that advances in battery technology will deliver adequate range and durability at an affordable cost. Third, that most customers will accept any functional limitations intrinsic to electrochemical energy storage. While the first two are subjects of active research and vigorous policy debate, the third is treated virtually as a given. Popular statements to the effect that ``because 70% of all daily travel is accomplished in less than 100 miles, mass deployment of 100 mile EVs will electrify 70% of all travel'' are based on collections of one-day travel reports such as the National Household Travel Survey, and so effectively ignore the complexities of individual needs. We have analyzed the day-to-day variations of individual vehicle usage in multiple regions and draw very different conclusions. Most significant is that limited EV range results in a level of inconvenience that is likely to be unacceptable to the vast majority of vehicle owners, and for those who would accept that inconvenience, battery costs must be absurdly low to achieve any economic payback. In contrast, the plug-in hybrid (PHEV) does not suffer range limitations and delivers economic payback for most users at realistic battery costs. More importantly, these findings appear to be universal in developed nations, with labor market population density being a powerful predictor of personal vehicle usage. This ``scalable city'' hypothesis may prove to a powerful predictor of the evolution of transportation in the large cities of the developing world.

  14. Economics of electricity

    Science.gov (United States)

    Erdmann, G.

    2015-08-01

    The following text is an introduction into the economic theory of electricity supply and demand. The basic approach of economics has to reflect the physical peculiarities of electric power that is based on the directed movement of electrons from the minus pole to the plus pole of a voltage source. The regular grid supply of electricity is characterized by a largely constant frequency and voltage. Thus, from a physical point of view electricity is a homogeneous product. But from an economic point of view, electricity is not homogeneous. Wholesale electricity prices show significant fluctuations over time and between regions, because this product is not storable (in relevant quantities) and there may be bottlenecks in the transmission and distribution grids. The associated non-homogeneity is the starting point of the economic analysis of electricity markets.

  15. Quantum, Photo-Electric Single Capacitor Paradox

    CERN Document Server

    Kapor, Darko

    2009-01-01

    In this work single capacitor paradox (a variation of the remarkable two capacitor paradox) is considered in a new, quantum discrete form. Simply speaking we consider well-known usual, photoelectric effect experimental device, i.e. photo electric cell, where cathode and anode are equivalently charged but non-connected. It, obviously, represents a capacitor that initially, i.e. before action of the photons with individual energy equivalent to work function, holds corresponding energy of the electrical fields between cathode and anode. Further, we direct quantum discretely photons, one by one, toward cathode where according to photo-electrical effect electrons discretely, one by one, will be emitted and directed toward anode. It causes discrete discharge of the cell, i.e. capacitor and discrete decrease of the electrical field. Finally, total discharge of the cell, i.e. capacitor, and total disappearance of the electrical field and its energy will occur. Given, seemingly paradoxical, capacitor total energy loss...

  16. Chirping response of weakly electric knife fish (Apteronotus leptorhynchus) to low-frequency electric signals and to heterospecific electric fish.

    Science.gov (United States)

    Dunlap, K D; DiBenedictis, B T; Banever, S R

    2010-07-01

    Brown ghost knife fish (Apteronotus leptorhynchus) can briefly increase their electric organ discharge (EOD) frequency to produce electrocommunication signals termed chirps. The chirp rate increases when fish are presented with conspecific fish or high-frequency (700-1100 Hz) electric signals that mimic conspecific fish. We examined whether A. leptorhynchus also chirps in response to artificial low-frequency electric signals and to heterospecific electric fish whose EOD contains low-frequency components. Fish chirped at rates above background when presented with low-frequency (10-300 Hz) sine-wave stimuli; at 30 and 150 Hz, the threshold amplitude for response was 1 mV cm(-1). Low-frequency (30 Hz) stimuli also potentiated the chirp response to high-frequency ( approximately 900 Hz) stimuli. Fish increased their chirp rate when presented with two heterospecific electric fish, Sternopygus macrurus and Brachyhypopomus gauderio, but did not respond to the presence of the non-electric fish Carassius auratus. Fish chirped to low-frequency (150 Hz) signals that mimic those of S. macrurus and to EOD playbacks of B. gauderio. The response to the B. gauderio playback was reduced when the low-frequency component (electric signals of heterospecific electric fish, and the low-frequency components of heterospecific EODs significantly influence chirp rate. These results raise the possibility that chirps function to communicate to conspecifics about the presence of a heterospecific fish or to communicate directly to heterospecific fish.

  17. Electric-bicycle propulsion power

    Energy Technology Data Exchange (ETDEWEB)

    Oman, H.; Morchin, W.C. [Electro-Bicycle, Inc., Auburn, WA (United States); Jamerson, F.E. [Electric Battery Bicycle Co., Naples, FL (United States)

    1995-12-31

    In a human-powered hybrid electric vehicle (HPHEV) the travel distance available from a single battery charge can be lengthened with power from another source, the cyclist`s leg muscles. In a battery-powered electric bicycle the propulsion power goes mostly into overcoming aerodynamic drag. For example, at 18 km per hour (11 miles per hour) this drag represents 200 watts at the tire-to-road interface for a typical cyclist`s shape and clothing. Today`s typical electrical bicycle is propelled by a high-speed dc motor which is powered from a lead-acid battery. The combined efficiency of the motor and its speed-reducing gears is 50 to 65 percent. In this paper we calculate available travel distances, as a function of speed, grade, and the battery energy-content as measured in watt-hours per kg. We show the effect of battery cost and charge/discharge cycle-life on travel cost in terms of cents per kilometer travelled. Designs used in today`s electric bicycles are illustrated.

  18. 小脑顶核电刺激对脑梗死患者认知功能的影响%Effect of fastigial nucleus electric stimulation on cognitive function of patients with cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    隆昱洲; 雷进; 罗丽华; 尚正良; 刘姚

    2013-01-01

    目的:探讨小脑顶核电刺激对脑梗死患者认知功能的影响.方法:脑梗死患者270例,随机分成治疗组和对照组各135例,均接受常规药物治疗,治疗组在此基础上加用小脑顶核电刺激,于治疗前和治疗后2周、3个月、6个月进行MoCA量表、威斯康星卡片分类测验(WCST)、Stroop色词测验(SCWT)、连线测验、语词流畅性测验、数字广度分测验、符号-数字分测验评定.结果:治疗后2周,两组在各项认知测验方面均较治疗前有改善,差异有统计学意义,治疗组分数较对照组提高更明显.治疗后3个月,治疗组在连线测验、SCWT测验耗时数方面均较治疗后2周有改善,差异有统计学意义,而在其余各项认知测验分数较2周时有改善,但差异无统计学意义.对照组在各项认知测验分数方面与治疗后2周相比,均有下降,差异有统计学意义.治疗后6个月,治疗组各项认知测验与治疗后3个月相比,差异无统计学意义,而对照组在各项认知测验分数均有下降,差异有统计学意义.治疗后2周、3个月、6个月两组间各项认知测验评分比较,存在差异,治疗组的评分好于对照组.结论:电刺激小脑顶核能改善脑梗死患者的认知功能.%Objective To investigate the effect of fastigial nucleus electric stimulation on cognitive function of patients with cerebral infarction. Methods 270 patients with cerebral infarction were divided into treatment and control group, and all be treated with routine treatment. The treatment group was given fastigial nucleus electric stimulation. All the patients were evaluated with Montreal Cognitive Assessment (MoCA), Wisconsin card sorting test (WCST), Stroop color word test (SCWT), trail making test A, verbal fluency test, digit span, symbols-digital test before treatments, 2 weeks, 3 months and 6 months after treatments. Results 2 weeks after treatment, various cognitive test grades significantly improved in treatment

  19. 经皮神经电刺激联合膀胱功能再训练对神经源性膀胱功能恢复的影响%Influence of percutaneous nerve electrical stimulation in combination with bladder function retraining on function recovery of patients with neurogenic bladder

    Institute of Scientific and Technical Information of China (English)

    鄢茵; 管细红; 童华章

    2016-01-01

    Objective:To probe into the influence of percutaneous nerve electrical stimulation in combination with bladder function retraining on function recovery of patients with neurogenic bladder.Methods:A total of 86 ca-ses of patients with neurogenic bladder after spinal cord injury were selected as the research objects and were randomly divided into observation group and control group,43 cases in each.The patients in control group were given conventional bladder function retraining,besides that the patients in observation group received percutane-ous nerve electrical stimulation for two months.The residual urine volume,bladder capacity and complications in both groups of patients were compared before and after the intervention.Results:After the intervention,the bladder capacity in patients in observation group was greater than that in control group,residual urine volume was less than that in control group,the difference was statistically significant (P<0.05);the incidences of urina-ry tract infection,bladder stones and hydronephrosis in observation group were lower than that in control group,and there were statistically significant differences between both groups (P <0.05).Conclusion:Percuta-neous nerve electrical stimulation in combination with bladder function retraining could effectively increase blad-der capacity,reduce the residual urine volume and the incidence of complications.%[目的]探讨经皮神经电刺激联合膀胱功能再训练对神经源性膀胱功能恢复的影响。[方法]选择86例脊髓损伤后神经源性膀胱病人为研究对象,随机分为观察组和对照组各43例。对照组给予常规膀胱功能再训练,观察组在此基础上给予2个月的经皮神经电刺激治疗。观察比较两组病人干预前后膀胱容量、残余尿量以及并发症发生情况。[结果]干预后,观察组病人膀胱容量大于对照组,残余尿量少于对照组,差异具有统计学意义(P <0.05);观察组病人尿路感

  20. Market Monitoring and Analysis: Electricity Sector

    Directory of Open Access Journals (Sweden)

    Helga Zogolli

    2015-10-01

    Full Text Available EU electricity liberalisation remains an essential energy reform programme, in scale in any other major region of the world. While other regions of the world have seen major pauses to their energy market reforms (most notably in the United States, the EU in the form of the European Commission, continues to press ahead. Electricity market power in Albania is in a difficult situation as a consequence of the lack of the adequate home-brew electricity resources and the great dependency from the hydro resources, inadequacy of the interconnections capacity with the neighbouring networks of electricity power, the considerable technical and economic barriers, and the difficult financials.In countries where no “official” power pool has been set up, different kinds of privates’ entities, e.g. generators, distributors, traders, large consumers, stock exchanges, system operator etc. or a combination of them, have promoted the creation of PX-s. The idea is that because electricity is a homogeneous product, standardized contracts can be traded on organized marketplaces. Since such an initiative was not forbidden by any law or by the European Directives many project have emerged in response to different motivations.This process in Europe, known as the liberalization process, has had a wide impact on the European electricity industry.Electricity market liberalisation is the opening of the market to competition; the extension of vertical unbundling of transmission and distribution from the generation and retailing; and the introduction of an independent regulator.The focus of this project is an analysis of the role of electricity PX-s in the recently liberalized electricity markets of Europe. In the context of creating “a” competitive electricity market at a European level, the key questions considered are the functioning of these PX-s with respect to electricity characteristics, market design and regulatory framework. Keywords: Energy,‘Placing on

  1. Study on influence of helicobacter pylori infection on gastric electrical parameters in functional dyspepsia%幽门螺杆菌感染影响功能性消化不良胃电参数探讨

    Institute of Scientific and Technical Information of China (English)

    周慧明; 沈磊

    2015-01-01

    Objective To investigated the influence of helicobacter pylori (HP) infection on gastric electrical parameters in functional dyspepsia (FD) .Methods The patients with FD from January 2011 to December 2012 were selected and divided into the HP positive group and the HP negative group .50 healthy persons undergoing physical examination were selected as the healthy control group .The adverse symptoms and surface electrogastrogram were examined and the data were analyzed .Results The HP negative groups was lower than the HP positive group in the aspects of abdominal pain ,belching ,vomiting ,regurgitation ,early satiety and heartburn (P < 0 .05) ;relative to the healthy control group ,T% ,B% ,N% ,DF and DP before and after meal in the HP positive group and DF ,DP and N%in the HP negative group had statistically significant differences (P< 0 .05) ;relative to the HP negative groups ,B% , N% ,DF and DP before and after meal in the HP positive group had statistically significant differences (P < 0 .05) . Conclusion HP infection could aggravate the adverse symptoms and lead to the gastric electric rhythm disorders in FD patients .%目的:探讨幽门螺杆菌感染对功能性消化不良胃电参数的影响。方法选取该院2011年1月至2012年12月收治的功能性消化不良患者,分为幽门螺杆菌阳性组和幽门螺杆菌阴性组,另选取该院门诊体检的健康者50例作为健康对照组,分别检测各组患者的不良症状和体表胃电图,分析数据。结果幽门螺杆菌阴性组在腹痛、暖气、呕吐、反流、早饱和烧心低于幽门螺杆菌阳性组(P<0.05);相对于健康对照组,幽门螺杆菌阳性组在餐前后正常胃电慢波百分比(N%)、餐后胃动过缓百分比(B%)、餐前后胃动过速百分比(T %)、主频(DF)、主功率(DP)和幽门螺杆菌阴性组在餐后 N%、DF 、DP 均差异有统计学意义(P<0.05);相对于幽门螺杆菌阴性组

  2. 功能性电刺激结合智能运动对脑卒中偏瘫患者运动功能的影响%Functional electrical stimulation combined with intelligent motion effects on motor function of hemiplegic pa-tients with cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    耿尚勇; 李月春; 李峰

    2014-01-01

    目的:应用功能性电刺激结合智能运动治疗脑卒中偏瘫患者,并观察其疗效,探讨脑卒中患者康复治疗的新方法。方法入选我院神经科经头颅C T或头颅M RI检查证实的脑卒中偏瘫患者110例,随机分为4组,所有患者均给予神经内科常规治疗及基础康复。A组加用功能性电刺激仪智能运动进行同步智能运动训炼;B组单用功能性电刺激,C组单用智能运动系统进行肢体运动,D组常规康复治疗。康复6周,治疗前后采用 Fugl-Meyer运动功能量表(FMA)、Berg平衡量表(BBS)、Barthel指数评定(BI)进行评定。结果4组治疗后FMA、BBS、BI评分比较差异均有统计学意义(P<0.05);治疗后A组评分与其他3组相比,差异有统计学意义(P<0.05),说明A组功能改善最显著;B组、C组治疗后与D组相比差异有统计学意义(P<0.05),说明B组、C组治疗较D组有效,功能改善较D组明显,但治疗后B组、C组组间对比差异无统计学意义( P>0.05)。结论在基础康复治疗上进行功能性电刺激结合智能运动系统训练,对脑卒中患者偏瘫会产生积极影响,对患者上下肢运动功能,平衡能力,均有积极改善作用,最终改善了脑卒中偏瘫患者的日常生活能力,提高患者生存和生活质量,明显优于单纯基础康复及基础康复加功能性电刺激或单纯智能运动,为脑卒中偏瘫患者康复提供了新方法。%Objective To observe the efficacy of functional electrical stimulation combined with intelligent motion on motor function of hemiplegic patients with cerebral infarction , and to explore new methods for rehabilitation in stroke pa-tients.Methods One hundred and ten cerebral apoplexy patients with hemiplegia confirmed by CT or head MRI admitted to our hospital had been chosen and divided into 4 groups ,who were all given general treatment and infrastructure rehabilitation

  3. Electric power monthly

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    The Energy Information Administration (EIA) prepares the Electric Power Monthly (EPM) for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. This publication provides monthly statistics for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source, consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead.

  4. Thermoacoustic magnetohydrodynamic electrical generator

    Science.gov (United States)

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1986-01-01

    A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1,000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.

  5. Electrical system architecture

    Science.gov (United States)

    Algrain, Marcelo C.; Johnson, Kris W.; Akasam, Sivaprasad; Hoff, Brian D.

    2008-07-15

    An electrical system for a vehicle includes a first power source generating a first voltage level, the first power source being in electrical communication with a first bus. A second power source generates a second voltage level greater than the first voltage level, the second power source being in electrical communication with a second bus. A starter generator may be configured to provide power to at least one of the first bus and the second bus, and at least one additional power source may be configured to provide power to at least one of the first bus and the second bus. The electrical system also includes at least one power consumer in electrical communication with the first bus and at least one power consumer in electrical communication with the second bus.

  6. 功能神经导航引导下的直接电刺激术在功能区肿瘤手术神经功能保护中的应用%Application of navigation-assisted direct electrical stimulation in protection of neurologic function in tumor surgery located at functional areas

    Institute of Scientific and Technical Information of China (English)

    钟平; 姚一; 江建东; 张小斌; 高志莹; 王逢鹏; 张卿云; 高登科

    2015-01-01

    目的 探讨功能神经导航引导下的直接电刺激术(DES)在功能区肿瘤手术神经功能保护中的应用.方法 厦门大学附属成功医院神经医学中心自2012年12月至2014年月10月在功能区肿瘤切除术中将双极刺激电极连接神经导航系统,在功能神经导航引导下行DES识别定位功能区并指导切除肿瘤10例,回顾性分析患者的疗效、手术前后语言和运动功能的变化.结果 10例肿瘤中全切7例,次全切3例;术中准确识别定位8例(80%)患者的相关功能区,其中识别皮质运动功能区4例,皮质下运动传导束6例,定位皮质下语言传导束1例;术后3例患者出现运动功能轻度下降,经康复锻炼后1例恢复至术前水平.无致残性运动功能障碍发生;术前存在语言功能障碍的4例患者术后仅1例出现语言功能轻度下降,另外3例获得一定程度的改善,其余患者术后语言功能均无影响.结论 功能神经导航引导下的DES可显著降低功能区肿瘤手术后神经功能障碍的发生率,改善患者生活质量.%Objective To explore the application of navigation-assisted direct electrical stimulation (DES) in the protection of neurologic function in surgery of tumors located at functional areas.Methods Ten patients with brain tumors at the functional areas,admitted to our hospital firom December 2012 to October 2014,were chosen;they were performed navigation-assisted DES using bipolar stimulating electrodes connected neuronavigation system.Preoperative motor function evaluated by Fugl-Meyer scale and verbal function evaluated by Western Aphasia Battery were underway.The motor and language functions and tumor resection rate were analyzed and compared before and after surgery.Results Total resection was achieved in 7 patients and subtotal resection in 3 patients.Accurate identification of related functional areas was successful in 8 patients (80%) in the operation,including 4 of the cortical motor function

  7. Electrical and electronic principles

    CERN Document Server

    Knight, S A

    1991-01-01

    Electrical and Electronic Principles, 2, Second Edition covers the syllabus requirements of BTEC Unit U86/329, including the principles of control systems and elements of data transmission. The book first tackles series and parallel circuits, electrical networks, and capacitors and capacitance. Discussions focus on flux density, electric force, permittivity, Kirchhoff's laws, superposition theorem, arrangement of resistors, internal resistance, and powers in a circuit. The text then takes a look at capacitors in circuit, magnetism and magnetization, electromagnetic induction, and alternating v

  8. Principles of electrical safety

    CERN Document Server

    Sutherland, Peter E

    2015-01-01

    Principles of Electrical Safety discusses current issues in electrical safety, which are accompanied by series' of practical applications that can be used by practicing professionals, graduate students, and researchers. .  Provides extensive introductions to important topics in electrical safety Comprehensive overview of inductance, resistance, and capacitance as applied to the human body Serves as a preparatory guide for today's practicing engineers

  9. Essays on electricity theft

    Science.gov (United States)

    Steadman, Keva Ullanda

    Electricity theft is a relatively unknown crime with high economic costs. In this dissertation, I try to identify the factors that motivate persons to steal electricity. First, I use a panel dataset of 97 countries spanning the five year period 2003--2007 to estimate a model that describes the effect of the unemployment rate, GDP per capita, male population and urbanization on theft, robbery and homicide rates. The results are consistent with previous empirical work on crime and economic opportunity. The second and main contribution of this paper is to estimate the same model using distribution loss as a proxy for electricity theft. The results show that the unemployment rate, a key explanatory economic factor for crime, cannot explain variation in electricity theft, although there is some evidence, albeit weak, supporting correlation in rich countries. Therefore, policies that target the reduction of property crime through a reduction in unemployment will have no effect on electricity theft. The third contribution relates to the role that political institutions play in the incentives to steal electricity. After control for socioeconomic factors, I find that there is no relationship between political governance indicators and electricity theft. In the second and third chapters, I compare the United States, a high income, low electricity theft country with Jamaica, a middle income, high electricity theft country. The effect of unemployment on electricity theft mirrors the results found in the first chapter. In the United States, electricity theft is affected by changes in economic conditions but in Jamaica, it is not. These results suggest that the state of institutions plays a role in how social norms are determined. Poor countries will be more likely than rich countries to have weak institutions with social norms that encourage electricity theft.

  10. Surface electrical properties experiment

    Science.gov (United States)

    Simmons, Gene; Strangway, David; Annan, Peter; Baker, Richard G.; Bannister, Lawrence; Brown, Raymon; Cooper, William; Cubley, Dean; deBettencourt, Joseph; England, Anthony W.; Groener, John; Kong, Jin-Au; LaTorraca, Gerald; Meyer, James; Nanda, Ved; Redman, David; Rossiter, James; Tsang, Leung; Urner, Joseph; Watts, Raymond

    1973-01-01

    The surface electrical properties (SEP) experiment was used to explore the subsurface material of the Apollo 17 landing site by means of electromagnetic radiation. The experiment was designed to detect electrical layering, discrete scattering bodies, and the possible presence of water. From the analysis of the data, it was expected that values of the electrical properties (dielectric constant and loss tangent) of lunar material in situ would be obtained.

  11. Bioprinting: Functional droplet networks

    Science.gov (United States)

    Durmus, Naside Gozde; Tasoglu, Savas; Demirci, Utkan

    2013-06-01

    Tissue-mimicking printed networks of droplets separated by lipid bilayers that can be functionalized with membrane proteins are able to spontaneously fold and transmit electrical currents along predefined paths.

  12. Carbon footprint of the Danish electricity transmission and distribution systems

    DEFF Research Database (Denmark)

    Turconi, Roberto; Astrup, Thomas Fruergaard

    &D) will likely grow. Several studies are available on renewable energy technologies, but only a few on transmission of electricity, and none on its distribution. This study provides life cycle inventory data for electricity distribution networks, and a life cycle GHG accounting of the Danish T&D networks....... The purpose was to evaluate the potential importance of environmental impacts associated with T&D in current and future electricity systems. Including the emissions from electricity T&D is needed to provide a full carbon footprint of electricity systems, and is essential to properly assess the environmental...... consequences of potential changes in an electricity system. So far, the basis for such assessments has not been available. The functional unit of this study was the delivery of one kWh of electricity in Denmark. The 2010 Danish electricity T&D networks were modeled, including power lines, transformers...

  13. Electrical installations and regulations

    CERN Document Server

    Whitfield, J F

    1966-01-01

    Electrical Installations and Regulations focuses on the regulations that apply to electrical installations and the reasons for them. Topics covered range from electrical science to alternating and direct current supplies, as well as equipment for providing protection against excess current. Cables, wiring systems, and final subcircuits are also considered, along with earthing, discharge lighting, and testing and inspection.Comprised of 12 chapters, this book begins with an overview of electrical installation work, traits of a good electrician, and the regulations governing installations. The r

  14. Electrically conductive cellulose composite

    Science.gov (United States)

    Evans, Barbara R.; O'Neill, Hugh M.; Woodward, Jonathan

    2010-05-04

    An electrically conductive cellulose composite includes a cellulose matrix and an electrically conductive carbonaceous material incorporated into the cellulose matrix. The electrical conductivity of the cellulose composite is at least 10 .mu.S/cm at 25.degree. C. The composite can be made by incorporating the electrically conductive carbonaceous material into a culture medium with a cellulose-producing organism, such as Gluconoacetobacter hansenii. The composites can be used to form electrodes, such as for use in membrane electrode assemblies for fuel cells.

  15. Sustainable Use of Electricity

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen

    1998-01-01

    An overview is presented of the need for keeping electricity consumption low, including a suggested definition of sustainable development. Specific attention is devoted to present and future electricity production´s contribution to the environmental problems. Prognoses are shown from before any...... analyses of the demand side indicated a need for such analyses. A model of the energy chain from primary energy to energy services is presented. Electricity consumption pattern are discussed. The vast options for saving electricity through more efficent end-use technologies are presented, and the barriers...

  16. Fire protection electrical engineering

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jung Min

    2000-03-15

    This book concentrates of electricity with current, voltage, power, ohms law, access of resistance, electrolytic analysis and battery, static on frictional electricity and electrostatic induction, coulomb's law, Gauss's law, condenser and capacity, magmatism on magnetic field and magnetic line of force, magnetic circuit, electromagnetic force, electromotive current, basic alternating current circuit, circuit network analysis, three-phase current, non-sinusoidal alternating current, transient phenomena, semiconductor, electric measurement on measurement over resistance, power, power rate and circuit tester, automatic control on introduction, term, classification, foundation of sequence control, logic circuit and basic logic circuit and electric equipment.

  17. Electric power annual 1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-06

    The Electric Power Annual presents a summary of electric utility statistics at national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts and the general public with historical data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. ``The US Electric Power Industry at a Glance`` section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; retail sales; revenue; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms.

  18. Semiconductor Electrical Measurements Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Semiconductor Electrical Measurements Laboratory is a research laboratory which complements the Optical Measurements Laboratory. The laboratory provides for Hall...

  19. Electrical applications 2

    CERN Document Server

    Tyler, David W

    1998-01-01

    Electrical Applications 2 covers the BTEC NII level objectives in Electrical Applications U86/330. To understand the applications, a knowledge of the underlying principles is needed and these are covered briefly in the text. Key topics discussed are: the transmission and distribution of electrical energy; safety and regulations; tariffs and power factor correction; materials and their applications in the electrical industry; transformers; DC machines; illumination; and fuse protection. Included in each chapter are worked examples which should be carefully worked through before progressing to t

  20. 基于正常行走模式的功能性电刺激对脑卒中恢复期患者行走功能的影响%Effects of functional electrical stimulation based on normal gait pattern on walking function in subjects with recovery of stroke

    Institute of Scientific and Technical Information of China (English)

    谭志梅; 姜文文; 燕铁斌; 吴伟; 宋荣

    2016-01-01

    目的 观察基于正常行走模式的功能性电刺激(FES)对脑卒中恢复期患者行走功能的影响.方法 选取2010年12月至2013年1月,在中山大学孙逸仙纪念医院及广东省中医院康复科住院的脑卒中患者,将符合入选标准的58例脑卒中恢复期患者分层后,应用Minimize计算机软件按2∶1∶1随机分为四通道FES组(n=29)、单通道FES组(n=15)、安慰电刺激组(n=14).3组患者常规治疗相同,四通道组给予基于正常行走模式的四通道FES治疗,单通道组给予单通道FES治疗,安慰电刺激组电刺激治疗与四通道组相同,但治疗时无电流输出.治疗每天1次,每次30 min,每周5次,共3周.患者分别在治疗前、治疗3周后接受下列评定:Fugl-Meyer运动评定中的下肢部分(FMA)、Berg平衡量表(BBS)、10m步行速度、表面肌电图检测步行中下肢主动肌/拮抗肌协同收缩率(CI)、改良Barthel指数(MBI).结果 治疗3周后,四通道组FMA、BBS、10 m步行速度分别由治疗前(23.0±2.2)、(31±71)和(0.23±0.10)分提高至(28.4±1.5)、(42±6)和(0.43±0.09)分;单通道组分别由治疗前(21.9±3.4)、(31±6)和(0.24±0.09)分提高至(26.6±1.8)、(38±5)和(0.34±0.08)分,安慰电刺激组分别由治疗前(23.6±3.0)、(33±5)和(0.25±0.09)分提高至(26.0±2.4)、(36±4)和(0.29±0.08)分,3组患者的FMA、BBS、10 m步行速度评分较治疗前均明显提高(P<0.05),且四通道组评分明显高于单通道组和安慰电刺激组(P<0.05).3组的MBI评分也明显提高,但组间比较未见明显差异(P>0.05).表面肌电图检测发现,3组患者患侧股四头肌/腘绳肌的CI均明显下降,与单通道组和安慰电刺激组比较,四通道组的CI下降幅度尤为明显(P<0.05).结论 基于正常行走模式的FES可显著改善脑卒中恢复期患者下肢的行走功能.%Objective To observe the effects of functional electrical stimulation (FES) based on normal gait pattern on walking function