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Artykuły w czasopismach na temat "AC stimulation"
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Ma, Xiaofeng, i Nobuo Suga. "Augmentation of Plasticity of the Central Auditory System by the Basal Forebrain and/or Somatosensory Cortex". Journal of Neurophysiology 89, nr 1 (1.01.2003): 90–103. http://dx.doi.org/10.1152/jn.00968.2001.
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Auditory conditioning (associative learning) or focal electric stimulation of the primary auditory cortex (AC) evokes reorganization (plasticity) of the cochleotopic (frequency) map of the inferior colliculus (IC) as well as that of the AC. The reorganization results from shifts in the best frequencies (BFs) and frequency-tuning curves of single neurons. Since the importance of the cholinergic basal forebrain for cortical plasticity and the importance of the somatosensory cortex and the corticofugal auditory system for collicular and cortical plasticity have been demonstrated, Gao and Suga proposed a hypothesis that states that the AC and corticofugal system play an important role in evoking auditory collicular and cortical plasticity and that auditory and somatosensory signals from the cerebral cortex to the basal forebrain play an important role in augmenting collicular and cortical plasticity. To test their hypothesis, we studied whether the amount and the duration of plasticity of both collicular and cortical neurons evoked by electric stimulation of the AC or by acoustic stimulation were increased by electric stimulation of the basal forebrain and/or the somatosensory cortex. In adult big brown bats ( Eptesicus fuscus), we made the following major findings. 1) Collicular and cortical plasticity evoked by electric stimulation of the AC is augmented by electric stimulation of the basal forebrain. The amount of augmentation is larger for cortical plasticity than for collicular plasticity. 2) Collicular and cortical plasticity evoked by AC stimulation is augmented by somatosensory cortical stimulation mimicking fear conditioning. The amount of augmentation is larger for cortical plasticity than for collicular plasticity. 3) Collicular and cortical plasticity evoked by both AC and basal forebrain stimulations is further augmented by somatosensory cortical stimulation. 4) A lesion of the basal forebrain tends to reduce collicular and cortical plasticity evoked by AC stimulation. The reduction is small and statistically insignificant for collicular plasticity but significant for cortical plasticity. 5) The lesion of the basal forebrain eliminates the augmentation of collicular and cortical plasticity that otherwise would be evoked by somatosensory cortical stimulation. 6) Collicular and cortical plasticity evoked by repetitive acoustic stimuli is augmented by basal forebrain and/or somatosensory cortical stimulation. However, the lesion of the basal forebrain eliminates the augmentation of collicular and cortical plasticity that otherwise would be evoked by somatosensory cortical stimulation. These findings support the hypothesis proposed by Gao and Suga.
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KNISLEY, STEPHEN B. "Exploring Cardiac Response to AC Stimulation". Journal of Cardiovascular Electrophysiology 12, nr 10 (październik 2001): 1185–86. http://dx.doi.org/10.1046/j.1540-8167.2001.01185.x.
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Su, Chen-Ying, Tzan Fang i Hsu-Wei Fang. "Effects of Electrostatic Field on Osteoblast Cells for Bone Regeneration Applications". BioMed Research International 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/7124817.
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Many external stimulations have been shown to promote bone regeneration. The effects of an alternating current (AC) electrostatic field, one of external stimulations, generated from a device with high voltage and low current output on human osteoblastic cell line have been investigated in this study. We investigated how human osteoblasts responded to an AC electrostatic field, and the output parameters were set as 1 kV and 160 μA. Our results showed that, under such condition, the AC electrostatic field had a downregulation effect on the production ability of alkaline phosphatase and type 1 collagen expression. However, the expression of osteocalcin gene was elevated on the end of EFID treatment suggesting that AC electrostatic field might be a potential stimulation for accelerating the differentiation of osteoblastic cells.
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Ma, Xiaofeng, i Nobuo Suga. "Plasticity of Bat's Central Auditory System Evoked by Focal Electric Stimulation of Auditory and/or Somatosensory Cortices". Journal of Neurophysiology 85, nr 3 (1.03.2001): 1078–87. http://dx.doi.org/10.1152/jn.2001.85.3.1078.
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Recent findings indicate that the corticofugal system would play an important role in cortical plasticity as well as collicular plasticity. To understand the role of the corticofugal system in plasticity, therefore, we studied the amount and the time course of plasticity in the inferior colliculus (IC) and auditory cortex (AC) evoked by focal electrical stimulation of the AC and also the effect of electrical stimulation of the somatosensory cortex on the plasticity evoked by the stimulation of the AC. In adult big brown bats ( Eptesicus fuscus), we made the following major findings. 1) Electric stimulation of the AC evokes best frequency (BF) shifts, i.e., shifts in frequency-response curves of collicular and cortical neurons. These BF shifts start to occur within 2 min, reach a maximum (or plateau) at 30 min, and then recover ∼180 min after a 30-min-long stimulus session. When the stimulus session is lengthened from 30 to 90 min, the plateau lasts ∼60 min, but BF shifts recover ∼180 min after the session. 2) The electric stimulation of the somatosensory cortex delivered immediately after that of the AC, as in fear conditioning, evokes a dramatic lengthening of the recovery period of the cortical BF shifts but not that of the collicular BF shift. The electric stimulation of the somatosensory cortex delivered before that of the AC, as in backward conditioning, has no effect on the collicular and cortical BF shifts. 3) Electric stimulation of the AC evokes BF shifts not only in the ipsilateral IC and AC but also in the contralateral IC and AC. BF shifts are smaller in amount and shorter in recovery time for contralateral collicular and cortical neurons than for ipsilateral ones. Our findings support the hypothesis that the AC and the corticofugal system have an intrinsic mechanism for reorganization of the IC and AC, that the reorganization is highly specific to a value of an acoustic parameter (frequency), and that the reorganization is augmented by excitation of nonauditory sensory cortex that makes the acoustic stimulus behaviorally relevant to the animal through associative learning.
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Chaudhry, A., i J. G. Granneman. "Effect of hypothyroidism on adenylyl cyclase activity and subtype gene expression in brown adipose tissue". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 273, nr 2 (1.08.1997): R762—R767. http://dx.doi.org/10.1152/ajpregu.1997.273.2.r762.
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Brown adipose tissue (BAT) expresses several adenylyl cyclase (AC) subtypes, and adrenergic stimulation selectively upregulates AC-III gene expression. Previous studies have described synergistic interactions between the sympathetic nervous system (SNS) and 3,5,3'-triiodothyronine (T3) on the regulation of gene expression in BAT. Because adrenergic stimulation also increases the activity of BAT type II thyroxine 5'-deiodinase (DII) and local T3 generation is important for many functional responses in BAT, we examined the effects of thyroid hormone status on the expression of various AC subtypes. Hypothyroidism selectively increased AC-III mRNA levels in BAT but not in white adipose tissue. Of the other subtypes examined, hypothyroidism did not alter AC-VI mRNA levels and slightly reduced AC-IX mRNA levels in BAT. The increase in AC-III expression was paralleled by an increase in forskolin-stimulated AC activity in BAT membranes. Sympathetic denervation of BAT abolished the increase in both AC activity and AC-III mRNA expression produced by hypothyroidism, but did not affect the expression of other subtypes. Surgical denervation also prevented the induction of AC-III in the cold-stressed euthyroid rat, but injections of T3 failed to alter AC-III expression in intact or denervated BAT. Our results indicate that T3 does not directly affect expression of AC-III. Rather, hypothyroidism increases BAT AC-III expression indirectly via an increase in sympathetic stimulation. Furthermore, our results strongly indicate that the increase in AC activity in hypothyroid BAT is due to increased expression of AC-III.
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Ward, Alex R. "Electrical Stimulation Using Kilohertz-Frequency Alternating Current". Physical Therapy 89, nr 2 (1.02.2009): 181–90. http://dx.doi.org/10.2522/ptj.20080060.
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Transcutaneous electrical stimulation using kilohertz-frequency alternating current (AC) became popular in the 1950s with the introduction of “interferential currents,” promoted as a means of producing depth-efficient stimulation of nerve and muscle. Later, “Russian current” was adopted as a means of muscle strengthening. This article reviews some clinically relevant, laboratory-based studies that offer an insight into the mechanism of action of kilohertz-frequency AC. It provides some answers to the question: “What are the optimal stimulus parameters for eliciting forceful, yet comfortable, electrically induced muscle contractions?” It is concluded that the stimulation parameters commonly used clinically (Russian and interferential currents) are suboptimal for achieving their stated goals and that greater benefit would be obtained using short-duration (2–4 millisecond), rectangular bursts of kilohertz-frequency AC with a frequency chosen to maximize the desired outcome.
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Raymaekers, S., Z. Van Duppen, K. Demyttenaere, L. Luyten, L. Gabriels, B. Nuttin i C. Bervoets. "Deep brain stimulation and anterior capsulotomy: The question of autonomy". European Psychiatry 41, S1 (kwiecień 2017): S323. http://dx.doi.org/10.1016/j.eurpsy.2017.02.249.
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IntroductionIn carefully selected treatment-refractory patients with obsessive compulsive disorder (OCD), deep brain stimulation (DBS) or anterior capsulotomy (AC) might be considered as a possible treatment. However, the direct intervention in the brain can raise questions about autonomy. Do patients still feel like they are in control of their actions when their behavior is changed by a surgical intervention?Objective/aimsTo examine in both AC and DBS patients whether these intervention influenced perception of autonomy. We aimed to discover any differences in these perceptions when comparing AC and DBS patients.MethodsWe conducted semi-structured interviews with AC and DBS patients. Interviews were recorded digitally and transcribed verbatim. We analyzed interviews in an iterative process based on grounded theory principles.ResultsWe interviewed 10 DBS patients and 6 AC patients. Sense of agency (the awareness that one is the author of his/her own actions) did not seem to be diminished by AC or DBS. However, especially DBS patients are aware of their dependency on a device for their well-being. Another important theme is authenticity (in how far patients perceive their actions and thoughts as matching their self-concept). Feelings of authenticity can be disturbed especially in cases of induced hypomania (for DBS) or apathy (for AC). OCD itself also has an impact on autonomy as patients describe a lack of freedom due to their disorder.ConclusionDespite extensive changes in emotions, behavior and even personal identity after DBS or AC surgery, perceived autonomy was not greatly altered in these OCD patients.Disclosure of interestMedtronic provided grants for research, education, and traveling to B. Nuttin and L. Gabriëls, who hold the Medtronic Chair for Stereotactic Neurosurgery in Psychiatric Disorders at KU Leuven. S. Raymaekers is supported by this Chair. B. Nuttin co-owns a patent on DBS in OCD.
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Ma, Xiaofeng, i Nobuo Suga. "Lateral Inhibition for Center-Surround Reorganization of the Frequency Map of Bat Auditory Cortex". Journal of Neurophysiology 92, nr 6 (grudzień 2004): 3192–99. http://dx.doi.org/10.1152/jn.00301.2004.
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Repetitive acoustic stimulation, auditory fear conditioning, and focal electric stimulation of the auditory cortex (AC) each evoke the reorganization of the central auditory system. Our current study of the big brown bat indicates that focal electric stimulation of the AC evokes center-surround reorganization of the frequency map of the AC. In the center, the neuron's best frequencies (BFs), together with their frequency–tuning curves, shift toward the BFs of electrically stimulated cortical neurons (centripetal BF shifts). In the surround, BFs shift away from the stimulated cortical BF (centrifugal BF shifts). Centripetal BF shifts are much larger than centrifugal BF shifts. An antagonist (bicuculline methiodide) of inhibitory synaptic transmitter receptors changes centrifugal BF shifts into centripetal BF shifts, whereas its agonist (muscimol) changes centripetal BF shifts into centrifugal BF shifts. This reorganization of the AC thus depends on a balance between facilitation and inhibition evoked by focal cortical electric stimulation. Unlike neurons in the AC of the big brown bat, neurons in the Doppler-shifted constant-frequency (DSCF) area of the AC of the mustached bat are highly specialized for fine-frequency analysis and show almost exclusively centrifugal BF shifts for focal electric stimulation of the DSCF area. Our current data indicate that in the highly specialized area, lateral inhibition is strong compared with the less-specialized area and that the specialized and nonspecialized areas both share the same inhibitory mechanism for centrifugal BF shifts.
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Kiritsy, Michael. "Burst Stimulation Could Be the Next Generation of Spinal Cord Stimulation". Topics in Pain Management 31, nr 11 (czerwiec 2016): 8–9. http://dx.doi.org/10.1097/01.tpm.0000484123.86649.ac.
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Surikova, Ekaterina Igorevna, Elena Frantsiyants, Irina A. Goroshinskaya, Yulia A. Pogorelova, Valeria A. Bandovkina, Irina Valerevna Neskubina, Andrey A. Maslov i in. "Does signet-ring cell carcinoma of the stomach (SRCC) need stimulation of neoangiogenesis?" Journal of Clinical Oncology 36, nr 4_suppl (1.02.2018): 33. http://dx.doi.org/10.1200/jco.2018.36.4_suppl.33.
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33 Background: Tumor neoangiogenesis is a complex coordinated process involving various regulatory molecules. Vascular endothelial growth factors, in particular VEGF-A, are important effectors. A multipotent TGF-β1 cytokine can modulate stromal angiogenesis reactions promoting the tumor growth. Our purpose was to study the function of the system of pro-angiogenic cytokines in tissues of stomach tumors of various histological types - adenocarcinoma (AC) and signet-ring cell carcinoma (SRCC). Methods: The concentrations of VEGF-A, VEGF-R1 and TGF-β1 were studied by ELISA in tumors, peritumoral zone and resection line tissues of gastric cancer patients without preoperative therapy: 15 patients with AC (T2-4N0-2M0, G2-G3, 50-84 years) and 10 patients with SRCC, comparable by sex, age and prevalence of cancer process. Results: Levels of VEGF-A, VEGF-R1 and TGF-β1 in the resection line tissues of AC and SRCC did not differ significantly. VEGF-A in AC tumor tissues exceeded significantly the levels in the resection line (by 2.3 times) and in the peritumoral zone (by 1.8 times). VEGF-A in SRCC tumor tissue did not differ significantly from the levels in the corresponding tissues of the resection line and peritumoral zone, but it was 2.6 times lower than in AC tumor tissues. VEGF-R1 levels in AC and SRCC were similar. TGF-β1 in AC tumor tissues was 3.2 and 2.6 times higher than in the resection line and peritumoral zone, respectively. TGF-β1 in SRCC tumor tissues did not differ from the levels in the peritumoral zone and in healthy tissues; TGF-β1 in tumor tissues was 3.2 times lower in SRCC than in AC. Conclusions: SRCC tumor tissues have significantly lower levels of pro-angiogenic VEGF-А and TGF-β1 cytokines, compared to AC tissues, which can indicate that SRCC has no need to form its own vasculature. It is probably associated with the biological characteristic of this histotype of gastric cancer - diffuse growth pattern, in contrast to the solid structure of AC.
Rozprawy doktorskie na temat "AC stimulation"
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Ly, Mai Thanh Graduate School of Biomedical Engineering Faculty of Engineering UNSW. "Electrical stimulation of cells involved in wound healing". Publisher:University of New South Wales. Graduate School of Biomedical Engineering, 2008. http://handle.unsw.edu.au/1959.4/41523.
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Problem investigated: Chronic wounds are not only a major burden to the patient arising from general pain and discomfort but also generate economic costs to both these individuals and the health care system. Various electrical stimulation regimes have been employed to study the effects of electrical stimulation on wound healing both in vivo and in vitro. In was hypothesised that electrical stimulation using various waveforms can modulate cell function, particularly cell migration. The aim of this thesis was to study the effects of electrical stimulation on cellular migration, in particular endothelial cells and fibroblasts, key cell types involved in wound healing. The impact of collagen matrix on cell migration was also assessed. Methods: Cells were seeded on either glass or collagen I substrate and stimulated with various electrical regimes via platinum electrodes connected to a constant current source. Cell migration was accessed by manual tracking of cell nuclei over a period of 3 hours from digital time-lapse images acquired during stimulation. Data from cell tracking were analysed for directional migration, migration rates and mean square displacement. Results: No directional cell migration for both endothelial cells and fibroblasts were observed when stimulated with either alternating or biphasic currents. However, surface substrate had impacted on cell motility with opposite effects being observed for the two cell types. Endothelial cells tended to migrate at a faster rate on collagen I substrate than on glass, compared with fibroblasts, which displayed a slower rate of migration on collagen I substrate. Significant changes in mean square displacement of biphasic current stimulated cells on collagen I substrate compared to unstimulated cells were also observed. Conclusion: This thesis has illustrated cell migration can be modulated by electrical stimulation, in particular asymmetric biphasic current. It has also been demonstrated surface substrate can impact cell migration.
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Kumar, Pragya Jai. "Effects of AC Stimulation on Chick DRG Neurite Growth, Density and Directionality". University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1376578750.
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Maslin, Michael Robin Daniel. "Plasticity, hemispheric asymmetries and the neural representation of sound". Thesis, University of Manchester, 2011. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:106396.
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The mature central nervous system (CNS) has the capacity to reorganise when there is a change in sensory input. However, studies using the N1 cortical auditory evoked potential, or its magnetic homolog N1m, have not consistently demonstrated evidence of plasticity in adults with late onset unilateral deafness. In addition, little is known about the time course of experience-related plasticity in adults with unilateral deafness. The aim of the studies described in this thesis was to investigate plasticity in adults with unilateral deafness, using N1 auditory evoked potentials. Deafness occurred as a result of surgery for the removal of an acoustic neuroma. The stimuli were 500-Hz and 4-kHz tones presented monaurally to the intact ear, and the data were analysed using global field power and dipole source analysis. In the first study (Chapter 3), hemispheric asymmetries in the N1 response were measured in a group of 24 normally hearing adults at presentation levels of 40, 60 and 80 dB sensation level (SL). The results revealed that the mean hemispheric asymmetry was greater for the 4-kHz stimulus but there was no significant effect of presentation level. In addition, the results revealed that the magnitude of hemispheric asymmetry depended on the ear of stimulation; a trend for larger asymmetries was observed following stimulation of the left ear. The results of the study provide confidence that the methodology is suitable for measuring hemispheric asymmetries in individuals with unilateral deafness. The effect of stimulus level is important since this will vary in plasticity studies involving individuals with late onset unilateral deafness due to their pure tone sensitivity thresholds. Clarifying the effect of stimulus frequency in normally hearing adults is important since the effect of stimulus frequency on plasticity following unilateral deafness has not been reported previously.In the second study (Chapter 4), N1 responses were measured in 19 adults with unilateral deafness (10 and 9 right- and left-sided deafness respectively). Stimuli were typically presented at 60 dB SL. The results revealed that there was significantly greater mean activity and a shift towards reduced hemispheric asymmetries compared with 19 audiogram-matched controls. Similar changes were apparent after both right- and left-sided deafness, and for both 500-Hz and 4-kHz stimuli. Therefore the results reveal evidence of experience-related plasticity that mirrors the findings reported in animal models. The reduced hemispheric asymmetries were reflected in the dipole source model used in this thesis by changes in dipole strength, location and orientation. These findings may explain the inconsistencies reported in previous studies that have used N1 or N1m, where dipole location and orientation have not always been taken into adequate consideration.In the third study (Chapter 5), longitudinal measurements were made in six adults just prior to the onset of complete unilateral deafness, and at 1-, 3- and 6-months after the onset (4 right-sided and 2 left-sided deafness respectively). The results from the second study were further analysed by splitting the data into two groups: nine participants with <2 years deafness and 10 with ≥2 year's deafness. The results from the longitudinal data revealed that there was a significant difference in mean activity across the four conditions. For both stimulus types an increase in mean activity occurred after the onset of deafness, and hemispheric asymmetries were reduced. The biggest changes occurred within 1-month, although further increases were noted in some individuals with ≥2 year's duration of deafness. Changes that continue over this period of time suggest different physiological mechanisms for plasticity within the human central auditory system.
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Kohli, Siddharth. "Closed-loop transcranial electrical stimulation : novel techniques for integrating electroencephalography and real-time adjustments of a.c. stimulation". Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/closedloop-transcranial-electrical-stimulation-novel-techniques-for-integrating-electroencephalography-and-realtime-adjustments-of-ac-stimulation(8058dac2-60a0-47e7-803a-8630a734305d).html.
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The goal of this thesis is to design methods and techniques for closed-loop transcranial Electric Stimulation (tES) based on feedback from ongoing neural activity. tES is a popular Non-Invasive Brain Stimulation (NIBS) approach and has been shown to modulate ongoing brain activity to affect behaviour. The application of these methods has major implications in both understanding the anatomy & function of the brain, and development of therapies for non-pharmacological intervention in mental health disorders. A review of existing brain imaging techniques compatible with tES shows that electroencephalography (EEG) is the most suitable method to pair with tES to design the closed-loop stimulation interface. Furthermore, of the different forms of tES, transcranial Alternating Current Stimulation (tACS) is the ideal method to use for closed-loop stimulation due to its ability to modulate ongoing neural activity in a phase specific manner. However, most studies have been limited to exploring changes in EEG before and after stimulation due to the presence of stimulation artifacts in the EEG data. A characterisation of these artifacts and a review of existing methods will identify the shortcomings of current practices. Thus, two novel algorithms for tACS artifact removal are be presented. Further, methods to judge the performance of such algorithms are currently limited and thus, new techniques to comprehensively test and verify these algorithms are presented, including the use of a novel phantom head model. A proof of concept for assessment of EEG activity during tACS is presented using novel methods that allow monitoring working memory during stimulation, via successful classification of data during two different tasks. This presents a novel technique to both verify artifact removal and also monitor ongoing neural activity during stimulation. Finally, an interface that executes the developed techniques in real-time was built. This toolbox is subsequently capable of providing closed-loop feedback to adjust tACS parameters based on ongoing EEG activity. It was designed to be as independent of hardware as possible, making it easy for other researchers to employ this toolbox in different labs across the world. This will allow for easier repeatability of methods in the field of tES research, which is a known issue. In summary, the novel techniques presented in this thesis are key steps towards development of closed-loop tACS as a tool for personalised, nonpharmacological therapy in mental health disorders.
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Michou, Emilia. "Mechanisms and therapeutic application of neurostimulation in the treatment of dysphagia after stroke". Thesis, University of Manchester, 2010. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:136896.
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"Long-lasting AC stimulation of myocardial tissue". Tulane University, 2002.
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Fibrillation, the life-threatening loss of cardiac output that occurs through a severe disruption in the normal propagation of the electrical wavefront responsible for triggering regular contraction of the heart, is treated through timely delivery of strong electrical shocks, termed defibrillation. While the clinical procedure is performed with direct current (DC) waveforms, recent experimental studies have shown that long-lasting alternating current (AC) waveforms can defibrillate the heart via novel mechanisms, such as entrainment and sustained depolarization. The purpose of this research is, through the use of computational models, to explore the mechanisms by which long-lasting AC shocks affect cardiac tissue and elucidate the role of entrainment and sustained depolarization in defibrillation The first phase of the study explores the affects of long-lasting AC stimuli on cardiac tissue in diastole (at rest), which insures that the tissue response is not obscured by the pre-shock state of the myocardium. Simulations are performed using models of single cardiac cells and sections of myocardial tissue, to determine important mechanisms at both the cell membrane and multicellular level. Entrainment and sustained depolarization are observed on both spatial levels; these responses are effected through both the simultaneous activation and resetting of individual ionic membrane channels, and the interaction between the regions of shock-induced virtual electrode polarization (VEP) during the shock. The conditions that give rise to various types of phase-locking of the transmembrane potential to the stimulus are also explored The second phase of the study focuses on the role that entrainment and sustained depolarization play in defibrillation by long-lasting AC shocks. In this study, long-lasting AC stimulus is applied to a computational model of cardiac architecture and fiber geometry based on the canine ventricles, in which a stable scroll wave has been induced. This study demonstrates that tissue entrainment by long-lasting high frequency shocks results in strong post-shock VEP, which result in higher defibrillation efficacy Results of this study elucidate the ability of long-lasting AC waveforms to entrain cardiac tissue, and illustrate the mechanisms by which depolarization is sustained during the shock. The study also reveals the frequency-dependent role of entrainment in successful cardioversion using long-lasting AC shocks. This study of long-lasting AC waveforms and their ability to defibrillate cardiac tissue contributes to the body of knowledge of defibrillation and explores mechanisms that could be further employed in the development of more efficient AC defibrillation protocolsacase@tulane.edu
Streszczenia konferencji na temat "AC stimulation"
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Haeffele, Benjamin D., i Robert J. Butera. "Modifying the Hodgkin-Huxley Model for High Frequency AC Stimulation". W 2007 3rd International IEEE/EMBS Conference on Neural Engineering. IEEE, 2007. http://dx.doi.org/10.1109/cne.2007.369731.
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Joseph, Laveeta, i Robert J. Butera. "Conduction Block in Unmyelinated Nerves Using High Frequency AC Stimulation". W 2007 3rd International IEEE/EMBS Conference on Neural Engineering. IEEE, 2007. http://dx.doi.org/10.1109/cne.2007.369738.
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Nitsch, K., T. Sobanski, K. Wisniewski i B. Licznerski. "AC response measurements of semiconductor gas sensors for temperature shift stimulation". W 26th International Spring Seminar on Electronics Technology: Integrated Management of Electronic Materials Production, 2003. IEEE, 2003. http://dx.doi.org/10.1109/isse.2003.1260558.
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Joseph, Laveeta, Benjamin D. Haeffele i Robert J. Butera. "Conduction block induced by high frequency AC stimulation in unmyelinated nerves". W 2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2007. http://dx.doi.org/10.1109/iembs.2007.4352641.
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Sakiyama, Ryota, Kazuya Matsumoto, Koji Yamamoto, Yusuke Morita i Eiji Nakamachi. "Development of AC Magnetic Field Stimulation Bio-Reactor for Three-Dimensional Culture of PC12 Cells". W ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70878.
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Recently, the electromagnetic stimulation method to enhance a nerve axonal extension has been attracting a great attention in the nerve regeneration. In this study, we design and fabricate a new 3D bio-reactor, which can implement uniform AC magnetic field (ACMF) stimulation on PC12 cells. We observe the morphology of PC12 cells using the multi photon microscope and evaluate effectiveness of uniform ACMF stimulation of the nerve axonal extension and the neural network generation. Firstly, a uniform ACMF stimulation bio-reactor was designed by using the pole piece structure. We searched an optimum structure using the magnetic field finite element analyses to obtain a uniform magnetic flux density in the culture region. Secondly, a chamber for 3D culture of PC12 cells was fabricated. PC12 cells were disseminated into a collagen gel which poured in the chamber. We evaluated the effects of uniform ACMF stimulation to enhance the nerve axonal extension. In our bio-reactor, an increase in axonal extension length and number of dendrites was observed under ACMF stimulation after 7 days culture. Finally, it was concluded that our uniform ACMF stimulation bio-reactor is an effective tool for the nerve axonal extension and the neural network generation.
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Ryzhii, Maxim, i Elena Ryzhii. "Simulation of the Effect of AC stimulation on Atrioventricular Node with Nonlinear Model". W 2020 11th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO). IEEE, 2020. http://dx.doi.org/10.1109/esgco49734.2020.9158159.
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Kanayama, Jumpei, Ibuki Nomura, Noriki Mochizuki, Takafumi Koike i Sousuke Nakamura. "Basic Evaluation of Carbonate Stimulus Amplification and Taste Change Using AC Electric Stimulation". W 2021 IEEE/SICE International Symposium on System Integration (SII). IEEE, 2021. http://dx.doi.org/10.1109/ieeeconf49454.2021.9382782.
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Asan, Ahmet S., i Mesut Sahin. "Modulation of Multiunit Spike Activity by Transcranial AC Stimulation (tACS) in the Rat Cerebellar Cortex". W 2019 41st Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 2019. http://dx.doi.org/10.1109/embc.2019.8856830.
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Matsumoto, Kazuya, Yusuke Morita i Eiji Nakamachi. "Development of Hybrid Electromagnetic and Mechanical Stimulation System for Enhancement of Nerve Axonal Extension". W ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65593.
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Recently, the electromagnetic and mechanical stimulation have been recognized as the effective extracellular environmental factor to enhance the defected peripheral nerve tissue regeneration. We designed and fabricated a bioreactor device, which can load the uniform AC magnetic field (ACMF) and the uniform tensile strain to stimulate PC12 nerve cell. For ACMF stimulation system, we used the pole piece structure to enable the uniform ACMF and in-situ microscopic observation. We confirmed the uniformity of magnetic field in the experiments. Further, the uniform strain in the stretch stimulation device was confirmed, even a slightly deviation from the designed strain was observed. It was a negligible small error. Next, we validated the effectiveness of PC12 axonal extension enhancement by two stimulation methodologies, ACMF and the cyclic stretch, under individual and combined stimulation conditions. ACMF showed a best enhancement effect on axonal extension, such as 70 μm at 96 h culture period, which rate is larger than the case of control. On the other hand, the stretch stimulation caused the exfoliation of cells. Hybrid stimulation succeeded to inhibit the exfoliation. However, the extensional rate was less than the case of ACMF. These results can be used to fabricate a bioreactor of nerve cell regeneration.
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Javier, Jeffrey, Taylor Hurdle, Sammie Fernandez i Kari Van Vliet. "Practical Dynamic Laser Stimulation Techniques for Complex Analog and Mixed Signal IC Failure Analysis". W ISTFA 2017. ASM International, 2017. http://dx.doi.org/10.31399/asm.cp.istfa2017p0390.
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Abstract The increasing electrical design and physical complexity of semiconductor devices, especially in the analog and mixed signal (AMS) applications, directly influences the development and evolution of fault isolation techniques. One of these techniques is Dynamic Laser Stimulation (DLS) which is widely used in the industry for effective identification of subtle failure mechanisms and soft defects especially for AC signal-related failures [1, 2]. However, for analysis of some complex AMS IC failure modes, the tool’s standard setup may not always be compatible with the biasing requirements of the device. For example, the setup would typically require expensive and intricate test systems (i.e. Automatic test equipment (ATE), SCAN tester, etc.) to be interfaced with the DLS tool for the analysis to be feasible and successful [3, 4]. This paper presents simple and practical techniques to implement DLS without the need for an expensive test support system. These techniques were applied in three different FA cases involving AMS ICs with complex and temperature-dependent failure modes. The results of subsequent analysis indicated success in isolating the exact defect sites.