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In recent years, electroceuticals have been spotlighted as an emerging treatment for various severe chronic brain diseases, owing to their intrinsic advantage of electrical interaction with the brain, which is the most electrically active organ. However, the majority of research has verified only the short-term efficacy through acute studies in laboratory tests owing to the lack of a reliable miniaturized platform for long-term animal studies. The construction of a sufficient integrated system for such a platform is extremely difficult because it requires multi-disciplinary work using state-of-the-art technologies in a wide range of fields. In this study, we propose a complete system of an implantable platform for long-term preclinical brain studies. Our proposed system, the extra-cranial brain activator (ECBA), consists of a titanium-packaged implantable module and a helmet-type base station that powers the module wirelessly. The ECBA can also be controlled by a remote handheld device. Using the ECBA, we performed a long-term non-anesthetic study with multiple canine subjects, and the resulting PET-CT scans demonstrated remarkable enhancement in brain activity relating to memory and sensory skills. Furthermore, the histological analysis and high-temperature aging test confirmed the reliability of the system for up to 31 months. Hence, the proposed ECBA system is expected to lead a new paradigm of human neuromodulation studies in the near future.

Introduction Patients with repaired tetralogy of Fallot (rTF) and severe pulmonary regurgitation frequently progress to dilation and dysfunction of the right ventricle (RV). It has been documented in the literature that there is a correlation between the duration of the QRS in the surface electrocardiogram and the hemodynamic parameters of the RV of these patients, suggesting the presence of a mechanical-electrical interaction. Purpose To determine if there is an association between the contraction delay in certain areas of the RV measured in M-mode echocardiography and the delay in electrical activation measured in the electroanatomic map (EAM) of RV in patients with rTF. Methods Unicentric and observational study of all patients with rTF undergoing EAM, echocardiography with study of RV asynchrony and cardiac magnetic resonance imaging (MRI). Activation delay in the antero-basal area and in the RV outflow tract (RVOT) in the EAM were both analysed (Figure 1A). The shortening delay in the same areas in M-mode echocardiography was also evaluated (Figure 1B, C). MRI data regarding volume and ejection fraction was also collected. Results 64 patients were included (36.7±10.6 years, 65% men). The mean total activation time of the RV (RV-TAT) was 127.3±42.4 ms. Activation mapping showed a recurrent pattern with beginning in the interventricular septum and ending in RV antero-basal region and/or RVOT. A linear positive correlation was observed between RV-TAT and the activation delay in both regions analysed (ρ=0.60 and ρ=0.52, respectively; p Conclusions There is a mechanical-electrical interaction in the RV of patients with rTF, with a negative correlation between the activation delay and RVEF and between mechanical and electrical activation delay in specific anatomical regions (regional mechanical-electrical interaction). These results may guide future studies on resynchronization in this heart disease. Figure 1. EAM and echocardiographic measures Funding Acknowledgement Type of funding source: None

In this paper, the action that lead to an efficiently Targeted Drug Delivery through the process of internalization is studied. Although one can expects that the probability to reach a target is, however in praxis this might not be clean in the sense that the surface of nanoparticles composed by ions exerts electrical interaction with charged electrically compounds around. The action to internalize the nanoparticle acquires relevance when one expects either electrical attraction or repulsion between nanoparticle and tumor or target tissue. This paper tries to model this through the concept of overlapping wave functions. The results would indicate that quantum numbers might be critic at the action of internalization.

Sorption of iodine on Beishan granite was studied by batch method. Great difference exists in the sorption behaviors of I− and IO3−. Under acidic condition, the sorption of IO3− improves dramatically, and IO3− could partly convert to I−. However, the sorption of I− is close to zero at all studied pH. Humic acid can slight improve the sorption of IO3−, but greatly improve the sorption of I− in acidic condition. The postulated sorption mechanisms of IO3− are electrical interaction and followed by reduction.

Non-productive adsorption of cellulase onto lignin restricted the movement of cellulase and also hindered the cellulase recycling in bioconversion of lignocellulose. In this study, effect of temperature and pH on adsorption and desorption of cellobiohydrolase (CBH) on lignin and its possible mechanism were discussed. It found that pH value and temperature influenced the adsorption and desorption behaviors of CBH on lignin. Different thermodynamic models suggested that the action between lignin and CBH was physical action. More CBH was adsorbed onto lignin, but lower initial adsorption velocity was detected at 50 °C comparing with 4 °C. Elevating pH value could improve desorption of cellulase from lignin. The changes of hydrophobicity and electric potential on protein surface may partially explain the impact of environmental conditions on the adsorption and desorption behaviors of CBH on lignin, and comparing to electrical interaction, the hydrophobicity may be the dominating factor influencing the behaviors.

Cardiac fibroblasts are widely represented in mammalian cardiac tissue. These cells are connected with cardiomyocytes by gap junctions and they have own changeable membrane potential, so that fibroblasts can influence cardiomyocyte electrical activity. This effect may be analyzed in mathematical models. Existing mathematical models of fibroblast-cardiomyocyte interaction allow anyone to study only electrical responses of the cardiomyocytes and fibroblasts to their electrical interaction. In our work we have considered the fibroblast influence on the cardiomyocytes mechanics. In numerical experiments we reveal significant changes in the cardiomyocyte action potential duration and force depending on the number of fibroblast connected with the cardiomyocyte.

Understanding how the brain process and store information is one of the most important quest in modern science. To this aim, in vitro neuronal models still represent a relevant approach, and a continuous improvement in the in-vitro methodologies for monitoring neurons electrical activity is in fact an important requirement. Moreover, with the advent of novel approaches in the development of in vitro 3D neuronal models, assessing the neural connectivity and monitoring the electrical activity in such complex cellular structures has lately become an important research objective that requires innovative platforms and fabrication approaches.In this preliminary work, we report on a customizable technique for developing 3D-vertical microelectrodes on standard planar MEAs in order to obtain system-on-a-chip platforms for neurophysiological applications. The proposed 3D-vertical microelectrodes are able to reliably record the electrical activity from different layers within a 3D neuronal culture, thus allowing a better understanding of the neurons electrical interaction at the three-dimensional level.

Background Tumor-treating fields (TTFs) have become an important, evidence-based modality in the treatment of glioblastoma (GBM). In patients requiring cardiac pacemakers, TTF therapy is complicated by theoretical concerns regarding possible electrical interaction between the devices. Case Description A 57-year-old man with past medical history of sick sinus syndrome requiring cardiac pacemaker implantation suffered an acute neurologic change associated with a left parieto-occipital lesion, which was found to be GBM. After completion of guideline-concordant chemoradiation, he chose to undergo TTF therapy. Because of the absence of cardiac symptoms and the theoretical risk of far-field sensing by the pacemaker of the TTF device (potentially resulting in pacemaker inhibition), the pacemaker was turned off before receiving TTF. Following TTF implementation, the patient responded well; he remains alive more than 25 months following his GBM diagnosis, exceeding the median 20.9-month survival of the recently completed phase III TTF randomized clinical trial for newly diagnosed GBM. Furthermore, he has exhibited neither cardiac morbidity nor adverse scalp reactions to TTF therapy. Conclusions The first reported case of successful TTF administration in a GBM patient with a previously implanted cardiac pacemaker may allay the concerns of neuro-oncologists, cardiologists, radiation oncologists, and all certified TTF prescribers regarding the applicability of TTF in suitable candidates with preexisting cardiac pacemakers. This case indicates that TTF therapy may be efficacious in patients with indwelling magnetic resonance image−conditional cardiac pacemakers turned to the off position and that physical removal of the pacemaker is not necessary before starting TTF.

Measurement tasks of modern micro- and nanometrology are posing a problem for current measurement instruments with decreasing structure sizes and rising aspect ratios. There is an open requirement for nanometre-resolving 3-D capable sensors and corresponding 3-D positioning systems to operate the sensors for 3-D measurements. A 3-D probing system based on electrical interaction is presented which is operated on a nanopositioning system type SIOS NMM-1. Furthermore, we demonstrate the progress and new possibilities for 3-D measurements with the nanopositioning and nanomeasurement machine NMM-1 and also with the application of a rotary kinematic chain. In addition new 3-D measurement routines for the NMM-1, also for micro-tactile probing systems as well as current plans, are shown.

We identify the interaction between nanoparticle and surface of material in the presence of an electric field. For theoretical calculation, we use the dyadic green function that includes with the method of image dipoles to analyze electrical interaction. We find that the electric field and the interaction potential which depend on the dielectric constant and surface roughness of material. Our numerical results demonstrate the electric field and the interaction potential which corresponds to the Van der Waals interaction and can be used to determine charges distribution on nanoparticle and surface of material.

Cochlear implants are devices which are surgically inserted into the internal ear, partially restoring hearing to people with profound deafness. Alternatives to improve levels of auditory perception are to increase the number of channels or frequency bands, that would need to increase the number of electrodes or electrode pairs per channel. Monopolar Virtual Channel (MPVC) stimulation mode increases the number of channels without increasing the number of electrodes using current steering. With this stimulation mode what still happens is interaction between the virtual channels, so some people who have these implants have not reported a striking improvement. In the present work, parameters of this electrical stimulation mode are modeled and evaluated. The results suggested that the maximal stimulation current can be determined so that no electrical interaction will occur between adjacent channels. If the stimulation current is higher than the calculated value, electrical interactions will occur between adjacent channels.

As an important part of the traction power supply system, the working state of catenary system is crucial to the train’s safe operation in high-speed railway. Since the complex mechanical and electrical interaction exists between pantograph and catenary system, the failure rate of catenary system is always high. Therefore, it is very necessary to detect and monitor the working state of the catenary fittings and eliminate the safety-threatening conditions in time.

Pantograph is a kind of current collecting device from the contact line to the locomotive. Due to the complex mechanical and electrical interaction between pantograph and catenary, the pantograph’s failure rate is always very high. Through the real-time monitoring for the pantograph state, the faults of pantograph can be found and the catenary state can also be judged in time, which is very beneficial to the repairmen and maintenance of pantograph and catenary. Because the pantograph works in an open environment for a long time and is affected by temperature, light, air pollution and other environmental factors influence, there are many kinds of faults.

Problems associated with the calculation of thermodynamic parameters of adsorption from solutions onto fiber surfaces were discussed. The chemical affinity of the adsorbate to textile fibers was determined. A method for calculating the chemical affinity that avoids the effect of uncertainties associated with neglect of intermolecular forces and electrical interaction in the adsorbed layer and in solution was proposed.

Much research on microbubbles and their drag reduction effect has been reported. However, few studies have focused on nanobubbles, which have sub-micrometer size. Mixtures of surfactants and polymers are known to reduce drag, but their use is limited because of environmental concerns. In this research, nanobubble mixtures for water and glycerol were passed through several sizes of micro-orifices and capillaries, and the resultant pressure drops, as compared with water and glycerol, were evaluated. For a small orifice (⩽50 μm) and capillary (⩽70 μm), the experimentally observed pressure drop was less than that for water. This phenomenon is considered in terms of interface behavior and attributed to the electrical interaction between an electric double layer and nanobubbles. The results of the present research suggest that the addition of nanobubbles to a liquid results in excellent drag reduction.

Chemical and electrical interaction within and between cells is well established. Just the opposite is true about cellular interactions via other physical fields. The most probable candidate for an other form of cellular interaction is the electromagnetic field. We review theories and experiments on how cells can generate and detect electromagnetic fields generally, and if the cell-generated electromagnetic field can mediate cellular interactions. We do not limit here ourselves to specialized electro-excitable cells. Rather we describe physical processes that are of a more general nature and probably present in almost every type of living cell. The spectral range included is broad; from kHz to the visible part of the electromagnetic spectrum. We show that there is a rather large number of theories on how cells can generate and detect electromagnetic fields and discuss experimental evidence on electromagnetic cellular interactions in the modern scientific literature. Although small, it is continuously accumulating.

A new type of collagen mimetic peptide, (PKG) n (POG)2n (DOG) n , with charged-domain ends had been designed and successfully prepared in this work, which self-assembled into collagen-like triple helices homotrimers. The collagen-like homotrimers underwent higher level of self-assembly via static electrical interaction between positive and negative domains. Transmission electron microscope (TEM) examinations showed three typical morphologies of homotrimer assembly, which were defined as film, bicontinuous and fibril morphology in this paper. The film was formed in the initial stage and gradually transformed to bicontinuous or fibril morphology to improve stability of the assemblies or decrease surface energy. Furthermore, mechanism of assembly process was proposed based on TEM observations and theoretical analyses of packing equation.

*** *** Mixtures of surfactants and polymers are known to reduce drag, but their use is limited because of environmental concerns. In this study, surfactant/nanobubble mixtures were passed through several sizes of micro-orifices, and the resultant pressure drops, as compared with water and only surfactant solution, were evaluated. For anionic surfactant/ nanobubble mixtures, the experimentally observed pressure drop was less than that for water. However, it was found that the pressure drop was greater than that for only anionic surfactant solution. In the case of non-ionic and cationic surfactants, the experimental results of mixed nanobubble liquids were less than those for water and only surfactant solution. This phenomenon is considered in terms of interface behavior and attributed to the electrical interaction between an electric double layer and nanobubbles.

Electrical coupling between cardiomyocytes is important in synchronous beating and normal heart functions. Cardiomyocytes are also electrically coupled to non-cardiomyocytes. The electrical interactions between cardiomyocytes and non-cardiomyocytes, or those between separated cardiomyocytes, are important for normal heart function because abnormalities of the coupling and variation of the cell population induce pathological heart functions and arrhythmias. In this study the three-dimensional time course of the electrical interaction between two rat neonatal cardiomyocyte sheets separated by non-cardiomyocyte sheets was analysed by a multiple-electrode extracellular recording system. The two cardiomyocyte sheets separated by a single- or double-layered mouse fibroblast NIH3T3 cell sheet coupled electrically at 113 ± 28 or 287 ± 87 min after layering, respectively. The time course of the electrical coupling, when the single-layer NIH3T3 cell sheet was inserted, is similar to that of a layered cardiomyocyte sheet. Immunocytological analysis and dye transfer assay suggested the formation of gap junctions at heterocellular junctions of cardiomyocytes and NIH3T3 cells. On the other hand, when a double-layered NIH3T3 cell sheet was inserted, an incomplete electrical coupling of two cardiomyocyte sheets, including a conduction delay, was observed. The electrical coupling of cardiomyocyte sheets was completely blocked (conduction block) by insertion of a triple-layered NIH3T3 cell sheet, a communication-defective HeLa cell sheet or a Ca2+-antagonist LaCl3-treated cell sheet. These electrophysiological analyses of heterogeneously stacked cell sheets might provide insights into complex electrical conduction systems that resemble those of native or damaged heart and transplanted tissues. Copyright © 2009 John Wiley & Sons, Ltd.

cited By 18; International audience; Carbon multi-walled nanotubes (MWCNTs) may have several dangerous effects on different cell systems, but the mechanisms responsible for their cytotoxicity are not well known yet. At present, very little is known about the electrical interactions between nanomaterials and cells. We aimed to verify whether MWCNT electrical properties could affect the so called "charge-sensitive" cell parameters, interacting with cellular electrical activity. Human macrophages were challenged with two fully characterised MWCNT samples, one tested as-prepared (MWCNT), the other one purified (by annealing at 2400 °C) and better electro-conductive (a-MWCNT). Our findings show that a-MWCNTs are less cytotoxic but possess a higher inflammatory potential, as compared to MWCNTs. Moreover, only annealed and better conductive MWCNTs affect significantly the mitochondrial membrane polarity, the intracellular pH and the reorganisation of cytoskeleton actin filaments, cell functions strictly dependent on electro-chemical mechanisms. Based on our results, there is evidence for electro-chemical interactions taking place between cell membranes and electro-conductive MWCNTs. Such a specific behaviour could have wide-range applications in the biomedical field, not only concerning those cellular systems (neuronal and bone cells) sensitive to electrical stimuli, but also other cell systems.

Electrical interaction of Engine Cooling Fan (ECF) with Heat Exchanger would strongly influence the electromagnetic behavior, and hence the EMC test results. Motivation and Objective for extensive and exhaustive component-level Electro-Magnetic Compliance (EMC) tests relies on close correlation and harmony between the vehicle-level and component-level test results. In fact, comprehensive component-level tests are presumed to indicate that most stringent possible vehicle-level Electro-Magnetic Interference (EMI) scenario is exercised in order to relieve expensive vehicle-level tests. This paper examines a component-level test scenario for an ECF according to OEM approved EMC test-plan mandating non-conductive air-flow load, thus resulting in AM band (0.53 MHz – 1.7 MHz) radiated emission deviations. Radiated Emissions (RE) deviations root-cause studies and troubleshooting indicates Amplitude Modulated (AM) band radiated emission compliance would result when a grounded metallic heat-exchanger is used.

Electro-thermal analysis of Si CMOS is performed. In order to have a higher degree of integration, the distance between two MOSFETs in CMOS structure must be decreased. But decreasing the distance between two MOSFETs results in an electrical interaction. In this research, we examine the interaction mechanism between n-type MOSFET and p-type MOSFET in Si CMOS in transient state. Numerical results show that the reason of the interaction between two MOSFET in CMOS is the forward bias at the pn junction with the substrate and that the timing of interaction becomes earlier and the leakage current increases as the distance between two MOSFET decreases. Furthermore, we investigate that the timing of interaction becomes later and the drain current decreases as the temperature of CMOS increases.

Background— The growing population with Fontan operation surviving into adulthood has significant morbidity and mortality rates from recurrent atrial tachyarrhythmias. We hypothesized that the structural characteristics and electrical behavior of atria may differ in these patients compared with those without arrhythmias. Methods and Results— We studied 33 consecutive patients (age, 25.4±9.5 years) with Fontan circulation, of whom 19 had a history of documented sustained atrial tachyarrhythmias. We analyzed their clinical and investigational data, including echocardiographic assessment of atrial dimensions and surface 12-lead ECG measurement of the P-wave duration and its dispersion between leads. Twenty age- and sex-matched healthy control subjects were also studied. First, patients who had the Fontan procedure overall had longer P-wave duration (144±33 versus 100±7 ms, P P P P P =0.01). Third, both P-wave duration and dispersion were significantly correlated to right atrial dimension within the Fontan group ( r =0.55, P =0.002, and r =0.56, P =0.002, respectively). Conclusions— Patients with atrial tachyarrhythmias late after Fontan operation have longer P-wave duration and P-wave dispersion and larger right atrial dimension than those without the arrhythmias; these abnormalities are interrelated. This observation represents an atrial mechano-electrical remodeling phenomenon in parallel to an increase in arrhythmia propensity in this vulnerable population and warrants further investigation.

The electrical interaction between two planar, parallel dissimilar surfaces, which may have different charged conditions arising from different ion-adsorption mechanisms, in an arbitrary electrolytic solution is investigated theoretically. The electrical interaction force and the interaction energy between these surfaces are evaluated, and analytical expressions for various charged conditions under the Debye-Huckel condition are derived. In general, assuming constant surface potential and assuming constant surface charge density lead respectively to the lower and the upper bounds in the electrical interaction energy between two surfaces. We show that assuming a linear relation between surface potential and surface charge density under the Debye-Huckel condition, as is often done in the literature, is appropriate for two planar parallel surfaces only but becomes inadequate for other orientations or nonplanar surfaces. The present approach does not have this limitation.

The complexity of the pattern of electrical activity of neural ensembles is due to the interaction of their elements. The interaction is associated with the presence of functional contacts between neurons. Since the time of Charles Sherrington, zones of contacts have been called “synapses.” Depending on the manner of conducting signals, synapses are divided into two types: electrical and chemical. The synapse of the former type is the zone of direct electrical interaction of the neurons. In this area of the membrane, neurons are in contact with each other, and currents are associated with the gradient of the potentials.

Using the Lagrangian formalism we attempt to calculate the interaction energy between the two bodies, nonconnected and connected, in a linear lattice. The obtained results show that the interaction is dependent on the dispersion relation ω (q). On this basis we calculate the binding energy of an ionic lattice and we have found a good agreement with experimental data.

The role of electrical interaction in wound healing has been recognized for nearly half of the last century. Based on the notion that wound healing may be facilitated by using electrical stimulation (referred to as electrotherapy), numerous animal model studies and clinical trials have been carried out to establish the effectiveness of electrotherapy. In spite of the concentrated effort, however, electrotherapy has not been approved by the U.S. FDA and remains poorly understood. Elucidation of the molecular and cellular mechanisms mediating facilitated wound healing is likely required, before rational electrotherapy can be devised and successfully implemented. Over the past six years, we have performed a series of in vitro experiments designed to identify the mechanisms mediating the cellular effects induced by exogenous application of electrical stimulation. The purpose of this review is to provide a description for such mechanisms (i.e., electrocoupling mechanisms) and to formulate an integrated model for these coupling mechanisms.

The electrical interaction between a particle and a boundary in an electrolyte solution is of both fundamental and practical significance. We consider the case of a spheroid, which can be nonrigid,...

The interaction between a colloidal particle and a surface plays an important role in various interfacial phenomena in both industrial and biological processes. Previous efforts are mainly based upon a point-charge model where the effect of the sizes of all the charged species is neglected. Here, we consider the case where a particle is covered by an ion-penetrable charged membrane, which mimics a biological entity, by taking this effect into account. We show that the sizes of the charged species are in the estimation of the electrical interaction force between particle and surface; the general trend of the result obtained is consistent with the experimental observations reported in the literature. The effects of the following key factors on the energy barrier for the particle−surface interaction are examined: the surface potential, the fixed charge density and the thickness of membrane layer, and the sizes of charged species.

The acidic internal pH environment, initial burst release and lack of targeting property are main limitations of poly(lactide-co-glycolide) (PLGA) nanoparticles for carrying proteins. In this study, ϵ-polylysine (ϵ-PL) was used as an anti-acidic agent and a protein protectant to prepare PLGA nanoparticles for the protein delivery. To obtain the liver-targeting capability, lactosylated PLGA (Lac-PLGA) was synthesized by conjugation of lactose acid to PLGA at both ends, and then used to prepare nanoparticles containing ϵ-PL by the nanoprecipitation method. Bovine serumal bumin (BSA), a negatively charged protein, was efficiently loaded into Lac-PLGA/ϵ-PL nanoparticles and exhibited significant decreased burst release in vitro, sustained release in the blood and increased liver distribution in mice after intravenous injections. The enhanced stability of BSA was due to its electrical interaction with ϵ-PL and the neutralized internal environment of nanoparticles. In conclusion, Lac-PLGA/ϵ-PL nanoparticle system can be used as a promising carrier for the negatively charged proteins.

The understanding of intermolecular electrical response is considered from the standpoint of both interaction energetics and property changes and from evaluation by ab initio calculations and by modeling. The objective of such understanding is to use property changes as better and better probes of behavior associated with intermolecular interaction and to design the most effective potential models for simulation of large molecular aggregations. The inherent transferability of electrical properties and the cooperativity of the complete electrical interaction is advantageous in connecting small cluster behavior with condensed phase behavior.

The electrical interaction of a system containing multiple, charged, rigid spherical particles of arbitrary orientation and size is analyzed theoretically. The equation governing the spatial variation of electrical potential is solved by a boundary integral method, and the electrical free energy of the system under consideration is evaluated. Several approximate analytical expressions for the electrical free energy are presented. We show that pairwise addition will, in general, overestimate the electrical free energy, except that when the electrical double layer around a particle is thin, it is approximately correct. Since the electrolyte concentration at which coagulation occurs is usually high, the classic analysis based on the interaction between two particles is representative of a system containing multiple particles and leads to reasonable results.