Recording of regional electrophysiological information by analysis of surface potentials to give a complete picture of the effects of the currents from the heart on the body surface. It has been applied to the diagnosis of old inferior myocardial infarction, localization of the bypass pathway in Wolff-Parkinson-White syndrome, recognition of ventricular hypertrophy, estimation of the size of a myocardial infarct, and the effects of different interventions designed to reduce infarct size. The limiting factor at present is the complexity of the recording and analysis, which requires 100 or more electrodes, sophisticated instrumentation, and dedicated personnel. (Braunwald, Heart Disease, 4th ed)
Recording of the moment-to-moment electromotive forces of the heart on a plane of the body surface delineated as a vector function of time.
Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.
An alkaloid found in the root of RAUWOLFIA SERPENTINA, among other plant sources. It is a class Ia antiarrhythmic agent that apparently acts by changing the shape and threshold of cardiac action potentials.
An impulse-conducting system composed of modified cardiac muscle, having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.

Clinical application of an integrated 3-phase mapping technique for localization of the site of origin of idiopathic ventricular tachycardia. (1/507)

BACKGROUND: Radiofrequency (RF) catheter ablation provides curative treatment for idiopathic ventricular tachycardia (VT). METHODS AND RESULTS: Nineteen consecutive patients with an idiopathic VT underwent RF catheter ablation. An integrated 3-phase mapping approach was used, consisting of the successive application of online 62-lead body surface QRS integral mapping, directed regional paced body surface QRS integral mapping, and local activation sequence mapping. Mapping phase 1 was localization of the segment of VT origin by comparing the VT QRS integral map with a database of mean paced QRS integral maps. Mapping phase 2 was body surface pace mapping during sinus rhythm in the segment localized in phase 1 until the site at which the paced QRS integral map matched the VT QRS integral map was identified (ie, VT exit site). Mapping phase 3 was local activation sequence mapping at the circumscribed area identified in phase 2 to identify the site with the earliest local endocardial activation (ie, site of VT origin). This site became the ablation target. Ten VTs were ablated in the right ventricular outflow tract, 2 at the basal LV septum, and 7 at the midapical posterior left ventricle. A high long-term ablation success (mean follow-up duration, 14+/-9 months) was achieved in 17 of the 19 patients (89%) with a low number of RF pulses (mean, 3.3+/-2.2 pulses per patient). CONCLUSIONS: This prospective study shows that integrated 3-phase mapping for localization of the site of origin of idiopathic VT offers efficient and accurate localization of the target site for RF catheter ablation.  (+info)

Ventricular excitation maps using tissue Doppler acceleration imaging: potential clinical application. (2/507)

OBJECTIVES: The purpose of this study is to validate the use of tissue Doppler acceleration imaging (TDAI) for evaluation of the onset of ventricular contraction in humans. BACKGROUND: Tissue Doppler acceleration imaging can display the distribution, direction and value of ventricular acceleration responses to myocardial contraction and electrical excitation. METHODS: Twenty normal volunteers underwent TDAI testing to determine the normal onset of ventricular acceleration. Two patients with paroxysmal supraventricular tachycardia and 30 patients with permanent pacemakers underwent introduction of esophageal and right ventricular pacing electrodes, respectively, and were studied to visualize the onset of pacer-induced ventricular acceleration. Eight patients with dual atrioventricular (AV) node and 20 patients with Wolff-Parkinson-White (WPW) syndrome underwent TDAI testing to localize the abnormal onset of ventricular acceleration, and the results were compared with those of intracardiac electrophysiology (ICEP) tests. RESULTS: The normal onset and the onset of dual AV node were localized at the upper interventricular septum (IVS) under the right coronary cusp within 25 ms before the beginning of the R wave in the electrocardiogram (ECG). In all patients in the pacing group, the location and timing of the onset conformed to the positions and timing of electrodes (100%). In patients with WPW syndrome, abnormal onset was localized to portions of the ventricular wall other than the upper IVS at the delta wave or within 25 ms after the delta wave in the ECG. The agreement was 90% (18 of 20) between the abnormal onset and the position of the accessory pathways determined by ICEP testing. CONCLUSIONS: These results suggest that TDAI is a useful noninvasive method that frequently is successful in visualizing the intramural site of origin of ventricular mechanical contraction.  (+info)

Dispersion of signal-averaged P wave duration on precordial body surface in patients with paroxysmal atrial fibrillation. (3/507)

AIMS: This study sought to investigate whether the spatial dispersion of signal-averaged P wave duration would be increased in patients with paroxysmal atrial fibrillation, by use of precordial mapping of the P wave signal-averaged ECG. METHODS AND RESULTS: The P wave signal-averaged ECG was recorded by the P wave-triggering method from 16 precordial leads in 55 patients with paroxysmal atrial fibrillation and 57 control subjects. As an index of the dispersion of signal-averaged P wave duration, we obtained the difference between the maximum and minimum in 16 recording sites. The dispersion was significantly greater in the patients with paroxysmal atrial fibrillation than the controls (26.6 +/- 9.5 vs 14.8 +/- 6.7 ms, P<0.0001). In 25 patients with symptomatic attacks of paroxysmal atrial fibrillation, the signal-averaged ECG was repeated 1 h after a single dose of orally administered pilsicainide, a new class Ic drug. These patients were prospectively followed-up for 10 +/- 11 months with pilsicainide. The rate of freedom from recurrence of paroxysmal atrial fibrillation attacks was significantly (P<0.0001) higher in patients with whom dispersion was decreased by the single dose (54%[7/13]) than in those in whom dispersion increased (8%[1/12]). CONCLUSION: Increased dispersion of signal-averaged P wave duration would play an important role in generating paroxysmal atrial fibrillation and would be useful in the prediction of drug efficacy to evaluate the change in dispersion by a single administration of pilsicainide.  (+info)

Mapping and ablation of ventricular tachycardia with the aid of a non-contact mapping system. (4/507)

OBJECTIVE: Treatment of ventricular tachycardia (VT) in coronary heart disease has to date been limited to palliative treatment with drugs or implantable defibrillators. The results of curative treatment with catheter ablation have proved disappointing because the complexity of the VT mechanism makes identification of the substrate using conventional mapping techniques difficult. The use of a mapping technology that may address some of these issues, and thus make possible a cure for VT with catheter ablation, is reported. PATIENTS AND INTERVENTION: The non-contact system, consisting of a multielectrode array catheter (MEA) and a computer mapping system, was used to map VT in 24 patients. Twenty two patients had structural heart disease, the remainder having "normal" left ventricles with either fasicular tachycardia or left ventricular ectopic tachycardia. RESULTS: Exit sites were demonstrated in 80 of 81 VT morphologies by the non-contact system, and complete VT circuits were traced in 17. In another 37 morphologies of VT 36 (30)% (mean (SD)) of the diastolic interval was identified. Thirty eight VT morphologies were ablated using 154 radiofrequency energy applications. Successful ablation was achieved by 77% of radiofrequency within diastolic activation identified by the non-contact system and was significantly more likely to ablate VT than radiofrequency at the VT exit, or remote from diastolic activation. Over a mean follow up of 1.5 years, 14 patients have had no recurrence of VT and only two target VTs have recurred. Five patients have had recurrence of either slower non-sustained, undocumented or fast non-target VT. Five patients have died, one from tamponade from a pre-existing temporary pacing wire, and four from causes unrelated to the procedure. CONCLUSION: The non-contact system can safely be used to map and ablate haemodynamically stable VT with low VT recurrence rates. It is yet to be established whether this system may be applied with equal success to patients with haemodynamically unstable VT.  (+info)

Low-frequency component of body surface potential maps identifies patients at risk for ventricular tachycardia. (5/507)

AIMS: To investigate the ability of spectral features of signal-averaged body-surface potential maps in identifying post-infarction patients who are at risk of developing ventricular tachycardia. METHODS AND RESULTS: We recorded 120 lead body surface potential maps during sinus rhythm in 135 subjects (45 patients with healed myocardial infarction but no history of ventricular tachycardia, 45 patients with both healed myocardial infarction and at least one episode of sustained ventricular tachycardia, and 45 normal subjects) and analysed spectral features of body surface potential maps selected on the basis of isoharmonic maps for given bands of the frequency spectrum. We found that in the low-frequency band (1-11 Hertz), the group-mean power spectra of leads located at isoharmonic map maxima were significantly different (P<0.0001) between the two groups of myocardial infarction patients. We estimated that this single feature alone can prospectively identify myocardial infarction patients at risk for ventricular tachycardia with a predictive accuracy of 74+/-6%. CONCLUSION: Our results suggest that the bulk of diagnostic information associated with arrhythmogenicity resides in the low-frequency band of the power spectrum. This finding is at variance with the established notion that only the high-frequency component of signal-averaged electrocardiograms carries such information.  (+info)

Signal averaged electrocardiography of Japanese. (6/507)

Although studies show that the ventricular tachycardia and sudden cardiac deaths caused by ischemic heart diseases affect Japanese less than Westerners, predictive accuracy of the signal averaged ECG for ventricular tachycardia and sudden cardiac deaths are almost the same as the results for Westerners. The recent prognosis of ischemic heart diseases is showing improvements along with the development of re-perfusion therapy, which is changing the significance of the signal averaged ECG. Therefore a clinical use for signal averaged ECG should be discussed in cases of cardiomyopathy which cause sudden cardiac deaths and other heart diseases. So it is necessary to redetermine normal values of the signal averaged ECG parameters. In this article, the following was reviewed on the basis of our studies regarding the clinical significance of the signal averaged ECG of Japanese and normal signal averaged ECG values. (1) System and gender specific differences on signal averaged ECG of Japanese, (2) His-Purkinje system, pre-P deflection and atrial late potential on signal averaged ECG, (3) Ventricular late potentials of Japanese.  (+info)

Use of electroanatomic mapping to delineate transseptal atrial conduction in humans. (7/507)

BACKGROUND: Interaction between wave fronts in the right and left atrium may be important for maintenance of atrial fibrillation, but little is known about electrophysiological properties and preferential routes of transseptal conduction. METHODS AND RESULTS: Eighteen patients (age 44+/-12 years) without structural heart disease underwent right atrial electroanatomic mapping during pacing from the distal coronary sinus (CS) or the posterior left atrium. During distal CS pacing, 9 patients demonstrated a single transseptal breakthrough near the CS os, 1 patient in the high right atrium near the presumed insertion of Bachmann's bundle and 1 patient near the fossa ovalis. The mean activation time from stimulus to CS os was 48+/-15 ms compared with 86+/-15 ms to Bachmann's bundle insertion (P<0.01) and 59+/-23 ms to the fossa ovalis (P=NS and P<0.01, respectively). During left atrial pacing, the earliest right atrial activation was near Bachmann's bundle in 5 and near the fossa ovalis in 4 patients. The activation time from stimulus to CS os was 70+/-15 ms compared with 47+/-16 ms to Bachmann's bundle (P<0.01) and 59+/-25 ms to the fossa ovalis (P=NS). Whereas the total septal activation time was not significantly different during CS pacing compared with left atrial pacing (41+/-16 versus 33+/-17 ms), the total right atrial activation time was longer during CS pacing (117+/-49 versus 79+/-15 ms; P<0.05). CONCLUSIONS: Three distinct sites of early right atrial activation may be demonstrated during left atrial pacing. These sites are in accord with anatomic muscle bundles and may have relevance for maintenance of atrial flutter or fibrillation.  (+info)

Computer-assisted animation of atrial tachyarrhythmias recorded with a 64-electrode basket catheter. (8/507)

OBJECTIVES: The aim of this study was to assess the value of a new mapping technique based on computer-assisted animation of multielectrode basket catheter (BC) recordings in patients with atrial arrhythmias. BACKGROUND: The three-dimensional activation patterns of cardiac arrhythmias are not completely understood owing to limitations of conventional mapping techniques. METHODS: The study included 32 patients with atrial tachycardia (AT) and 38 patients with atrial flutter (AFL). A software program was developed to analyze the activation patterns based on 56 bipolar electrograms recorded with a 64-electrode BC deployed in the right atrium (RA). RESULTS: The total time needed for the animation of activation patterns of atrial arrhythmias was 5 +/- 0.8 min. In 22 patients with right AT, the animated maps revealed that arrhythmia was unifocal in 15 patients, multifocal in 2 patients, polymorphic in 4 patients and reentrant in 1 patient. In 10 patients with left AT, breakthroughs on the right side of the septum (2 in 8 patients and 1 in 2 patients) and a left-to-right activation of the RA were demonstrated. In patients with typical AF, the reentrant excitation was a broad activation front with preferential propagation around the tricuspid annulus. In patients with atypical AFL, the reentry circuit involved one of the venae cavae and a line of block located in the posterior wall. CONCLUSIONS: The computer-assisted animation of multiple electrograms recorded with a BC is a valuable mapping tool that delineates the three-dimensional activation patterns of various atrial arrhythmias. The technique is appropriate for complex, short-lived or unstable arrhythmias.  (+info)

Body Surface Potential Mapping (BSPM) is a non-invasive medical technique used to record and analyze the electrical activity of the heart from the surface of the body. It involves placing multiple electrodes on the skin of the chest, back, and limbs to measure the potential differences between these points during each heartbeat. This information is then used to create a detailed, visual representation of the electrical activation pattern of the heart, which can help in the diagnosis and evaluation of various cardiac disorders such as arrhythmias, myocardial infarction, and ventricular hypertrophy.

The BSPM technique provides high-resolution spatial and temporal information about the cardiac electrical activity, making it a valuable tool for both clinical and research purposes. It can help identify the origin and spread of abnormal electrical signals in the heart, which is crucial for determining appropriate treatment strategies. Overall, Body Surface Potential Mapping is an important diagnostic modality that offers unique insights into the electrical functioning of the heart.

Vectorcardiography (VCG) is a type of graphical recording that depicts the vector magnitude and direction of the electrical activity of the heart over time. It provides a three-dimensional view of the electrical activation pattern of the heart, as opposed to the one-dimensional view offered by a standard electrocardiogram (ECG).

In VCG, the electrical potentials are recorded using a special array of electrodes placed on the body surface. These potentials are then mathematically converted into vectors and plotted on a vector loop or a series of loops that represent different planes of the heart's electrical activity. The resulting tracing provides information about the magnitude, direction, and timing of the electrical activation of the heart, which can be helpful in diagnosing various cardiac arrhythmias, ischemic heart disease, and other cardiac conditions.

Overall, vectorcardiography offers a more detailed and comprehensive view of the heart's electrical activity than traditional ECG, making it a valuable tool in clinical cardiology.

Electrocardiography (ECG or EKG) is a medical procedure that records the electrical activity of the heart. It provides a graphic representation of the electrical changes that occur during each heartbeat. The resulting tracing, called an electrocardiogram, can reveal information about the heart's rate and rhythm, as well as any damage to its cells or abnormalities in its conduction system.

During an ECG, small electrodes are placed on the skin of the chest, arms, and legs. These electrodes detect the electrical signals produced by the heart and transmit them to a machine that amplifies and records them. The procedure is non-invasive, painless, and quick, usually taking only a few minutes.

ECGs are commonly used to diagnose and monitor various heart conditions, including arrhythmias, coronary artery disease, heart attacks, and electrolyte imbalances. They can also be used to evaluate the effectiveness of certain medications or treatments.

Ajmaline is a type of medication known as a Class I antiarrhythmic agent, which is used to treat certain types of abnormal heart rhythms. It works by blocking the sodium channels in the heart muscle, which helps to slow down the conduction of electrical signals within the heart and can help to restore a normal heart rhythm.

Ajmaline is typically administered intravenously (through a vein) in a hospital setting, as it acts quickly and its effects can be closely monitored by healthcare professionals. It may be used to diagnose certain types of heart rhythm disturbances or to treat acute episodes of arrhythmias that are not responding to other treatments.

Like all medications, ajmaline can have side effects, including dizziness, headache, nausea, and chest pain. It is important for patients to be closely monitored while taking this medication and to report any unusual symptoms to their healthcare provider. Ajmaline should only be used under the close supervision of a qualified healthcare professional.

The heart conduction system is a group of specialized cardiac muscle cells that generate and conduct electrical impulses to coordinate the contraction of the heart chambers. The main components of the heart conduction system include:

1. Sinoatrial (SA) node: Also known as the sinus node, it is located in the right atrium near the entrance of the superior vena cava and functions as the primary pacemaker of the heart. It sets the heart rate by generating electrical impulses at regular intervals.
2. Atrioventricular (AV) node: Located in the interatrial septum, near the opening of the coronary sinus, it serves as a relay station for electrical signals between the atria and ventricles. The AV node delays the transmission of impulses to allow the atria to contract before the ventricles.
3. Bundle of His: A bundle of specialized cardiac muscle fibers that conducts electrical impulses from the AV node to the ventricles. It divides into two main branches, the right and left bundle branches, which further divide into smaller Purkinje fibers.
4. Right and left bundle branches: These are extensions of the Bundle of His that transmit electrical impulses to the respective right and left ventricular myocardium. They consist of specialized conducting tissue with large diameters and minimal resistance, allowing for rapid conduction of electrical signals.
5. Purkinje fibers: Fine, branching fibers that arise from the bundle branches and spread throughout the ventricular myocardium. They are responsible for transmitting electrical impulses to the working cardiac muscle cells, triggering coordinated ventricular contraction.

In summary, the heart conduction system is a complex network of specialized muscle cells responsible for generating and conducting electrical signals that coordinate the contraction of the atria and ventricles, ensuring efficient blood flow throughout the body.

Kavuru, Madhav S.; Vesselle, Hubert; Thomas, Cecil W. (1987). Advances in Body Surface Potential Mapping (BSPM) Instrumentation ... It also does not truly represent the center-of-heart potential due to the body parts the signals travel through. Leads I, II ... Electrodes are the actual conductive pads attached to the body surface. Any pair of electrodes can measure the electrical ... Both branches conduct action potentials at about 1 m/s. Interestingly, however, the action potential starts traveling down the ...
Interferometric Synthetic Aperture Radar (InSAR) can generate maps of surface deformation or elevation, using satellite radar ... In addition to a wide variety of commercial projects, they have a significant involvement with national and European bodies ... Offshore, NPA's Global Offshore Seep Project uses SAR data to detect oil seepage from potential reservoirs. ... NPA Satellite Mapping is the longest-established satellite mapping specialist in Europe, with expertise in geoscience ...
Sample types have included: surface and underground grab samples, surface and underground drill core samples, drill sludge ... In 1893, Map #27 by the Geological Survey Department was produced by E.R. Faribault to illustrate a report commissioned by the ... This comparison indicates that a potential for a larger deposits exists on Orex's property. Two different approaches to ... 1.19 to 2.42 g/t Main Ore Body: 19,500,000 tonnes @ 0.75 to 3.37 g/t West Goldbrook Area: 8,614,817 tonnes @ 0.53 to 0.84 g/t ...
Open-pit mines are used when deposits of commercially useful ore or rocks are found near the surface. It is applied to ore or ... It is important to consider the grade and economic value of the ore in the potential pit. Open-pit mines that produce building ... This is done through drilling of probe holes in the ground, then plotting each hole location on a map. The information gained ... through the holes with provide an idea of the vertical extent of the ore's body. This vertical information is then used to pit ...
... body surface potential mapping MeSH E01.370.405.245 - electroencephalography MeSH E01.370.405.245.100 - alpha rhythm MeSH ... body surface potential mapping MeSH E01.370.370.380.240.230 - electrocardiography, ambulatory MeSH E01.370.370.380.240.850 - ... body surface potential mapping MeSH E01.370.370.380.245 - electrophysiologic techniques, cardiac MeSH E01.370.370.380.250 - ... body surface potential mapping MeSH E01.370.405.240.230 - electrocardiography, ambulatory MeSH E01.370.405.240.850 - ...
... surface water-bodies, wetlands, coastal land use, ground-water targets, urban land use etc. have provided the basis for ... Assessing deforestation Mapping urban areas for planning purposes Delineating ocean areas with higher fish catch potential and ... The agency has executed several projects under National mapping missions wherein mapping and inventory of forests, wastelands, ... Mapping of forests and grasslands. Monitoring of forest encroachment and shifting cultivation Forest fire surveillance. Mapping ...
According to isoseismal maps. intensity VIII was felt in a narrow area near the epicenter. Isoseismal maps with intensity ... The tremor triggered numerous surface fissures on flat grounds spewing sand and water out of it. Multiple ground failures and ... The continental collision zone is seismically active with the potential to generate large earthquakes. The events happening ... one being 6.0 on the moment magnitude scale and the other is a 5.6 on the body-wave magnitude scale. It was assigned a maximum ...
Accordingly, the gravitational forces from the two massive bodies are in the same ratio as the masses of the two bodies, and so ... L2 is in deep space far away from any planetary surface and hence the thermal, micrometeoroid, and atomic oxygen environments ... Planned missions include the Interstellar Mapping and Acceleration Probe(IMAP), Aditya-L1 Mission and the NEO Surveyor. Sun- ... as in the effective potential contour plot above, they are nonetheless stable. The reason for the stability is a second-order ...
Areas PV and S2 both map the body surface. Functional neuroimaging in humans has revealed that in areas PV and S2 the face is ... using evoked potentials and electrical stimulation. Experiments involving ablation of the second somatosensory cortex in ... Individual neurons in areas PV and S2 receive input from wide areas of the body surface (they have large "receptive fields"), ... Areas S2 in the left and right hemispheres are densely interconnected, and stimulation on one side of the body will activate ...
... or a downhole tool lowered into a borehole which transects a body of mineralization. These methods can map out sulphide bodies ... Surface EM methods are based mostly on Transient EM methods using surface loops with a surface receiver, ... They are used to map the subsurface distribution of stratigraphy and its structure which can be used to delineate potential ... Reflection seismology and seismic refraction to map the surface structure of a region. Geodesy and gravity techniques, ...
This is a type of specialized brain and body scan used to map neural activity in the brain or spinal cord of humans or other ... It can also record signal from all regions of the brain, unlike EEG/MEG, which are biased toward the cortical surface. But fMRI ... The local field potential, which includes both post-neuron-synaptic activity and internal neuron processing, better predicts ... As this proportion fell, a map of blood flow in the brain was seen in the MRI. They verified this by placing test tubes with ...
Pressure in a static body of water increases proportionally to the depth below the surface of the water. The surfaces of ... This means that gravitational potential energy on a contour map is proportional to altitude. On a contour map, the two- ... The gravity potential is the gravitational potential energy per unit mass. In electrostatics the electric potential is the ... An example is the (nearly) uniform gravitational field near the Earth's surface. It has a potential energy U = m g h {\ ...
... facilitating its organic emergence from the white surface. Paul Ardenne described the marked paper as "both the surface of ... Jill O'Bryan: Mapping Resonances. Santa Fe, NM: Center for Contemporary Arts and Radius Books, 2017. Speer, Adriana. "Grounded ... "Penetrating layers of flesh: Carving in/out the bodies of Orlan and Medusa, Artaud and Marsyas," Women & Performance: a journal ... they allude to both drought and the potential for replenishment. In 2015, O'Bryan was commissioned by The Phillips Collection ...
... waves of spontaneous action potentials arise from the retinal ganglion cells and sweep across the retinal surface in the first ... Brain mapping can show how an animal's brain changes throughout its lifetime. As of 2021, scientists mapped and compared the ... Neural induction is often studied in Xenopus embryos since they have a simple body plan and there are good markers to ... They are thought to instruct the formation of two sensory maps- the retinotopic map and eye-specific segregation. Retinotopic ...
A sensory space can also map into a particular region on an animal's body. For example, it could be a hair in the cochlea or a ... Receptive fields can positively or negatively alter the membrane potential with or without affecting the rate of action ... through the bidimensional skin surface, being a receptive field for touch perception. ... and the body (Extrastriate body area). However, more recent research has suggested that the fusiform face area is specialised ...
Iron occurrences were observed during initial geological mapping of the area in the mid thirties but the economical potential ... Sixteen ore bodies extending for up to 3 km and 100m thick. Amenable to open pitting. Coal resource nearby suitable for blast ... The oxidised ores, extending up to 130m below ground surface, consist mainly of magnetite, martite and hydrogoethite. Two other ... The regional geology was mapped at 1:50 000 while the Hajigak deposit was mapped at 1:10 000. Focusing on the western area of ...
The probe has made a 3-D map of the Moon's surface and has provided some of the first images of Apollo equipment left on the ... To this end, a detailed mapping program identifies safe landing sites, locates potential resources on the Moon, characterizes ... Stardust intercepted comet Tempel 1 on February 15, 2011, a small Solar System body previously visited by Deep Impact on July 4 ... It was intended to help select landing sites for the Apollo program by mapping the Moon's surface. The program produced the ...
Groundwater flow directions can be determined from potentiometric surface maps of water levels in wells and springs. Aquifer ... Discontinuous sand bodies at the base of the McMurray Formation in the Athabasca Oil Sands region of northeastern Alberta, ... The criteria proposed by this approach attempt to encapsulate and measure all potential variables that play a role in defining ... Aquifers occur from near-surface to deeper than 9,000 metres (30,000 ft). Those closer to the surface are not only more likely ...
The residual Bouguer potential is contributed by the mantle. The undulation of the crust-mantle boundary, or the Moho surface, ... A separate free-air gravity anomaly map, Bouguer gravity anomaly map and a map of crustal thickness were produced along with ... Simply, if Mars is assumed to be a static perfectly spherical body of radius RM, provided that there is only one satellite ... Maps produced have included free-air gravity anomaly, Bouguer gravity anomaly, and crustal thickness. In some areas of Mars ...
The satellites use radar signals that are able to map a body of water based on the amount of disturbance on the surface from ... CSN uses images from a number of satellites in order to alert member states of potential oil spills. CSN offers near-real-time ... This allows the satellites to map and locate an accumulation of oil. Not only are these satellites able to map oil slicks, but ... When the oil is present on the water's surface, it creates a glassy area free of ripples. SAR satellites send radar signals ...
EMG measures action potentials, called Motor Unit Action Potentials (MUAPs), created during muscle contraction. A few common ... However, data from MEG and MRI can be combined to create images that approximately map the estimated location of the natural ... There are many processes that occur in the body which produce electrical signals that can be detected. Depending on the ... In the diagnostic role, surface EMG is a very informative method used to obtain relevant quantitative characteristics.[citation ...
Sparks often indicate the presence of a high voltage, or "potential field". The higher the voltage; the farther a spark can ... This plasma is heated to temperatures often greater than the surface of the Sun, and can cause small, localized burns. ... Conductive liquids, gels or ointments are often used when applying electrodes to a person's body, preventing sparks from ... Kryzhanovsky, L. N. (1989). "Mapping the history of electricity". Scientometrics. 17 (1-2): 165-170. doi:10.1007/BF02017730. ...
These points of contact can then be turned into a three-dimensional ellipsis, producing a surface map of the object. In hand ... The relationship between these two is described through a contact model, which is a set of the potential points of contact ... A robot hand interacts with static and deformable objects, described with soft-body dynamics. Sometimes, additional tools has ... can be used to produce a surface map or contact model of the object being grasped. For a robot to autonomously grasp an object ...
Other conservation efforts include habitat restoration, mapping of potential future habitats in Europe, expanded research, ... Rana latastei may attain a head-body length of 7.5 cm (3.0 in). Females tend to be slightly larger than males. Most frogs have ... Females lay eggs in a single, compact clump within 50 cm of the water surface, typically within 2 to 15 days of mating. Only ... Adults are found closer to bodies of water during the breeding season between February and April, and are more commonly found ...
In a rhizome, "culture spreads like the surface of a body of water, spreading towards available spaces or trickling downwards ... "map and not a tracing". They elaborate in the same section, "What distinguishes the map from the tracing is that it is entirely ... as the water is charged with pressure and potential to always seek its equilibrium, and thereby establish smooth space." ... Rather than narrativize history and culture, the rhizome presents history and culture as a map or wide array of attractions and ...
The chronaxie values for mammalian ventricles at body temperature range from 0.5 ms (human) to 2.0 to 4.1 ms (dog); this is an ... An electrode is inserted into the muscle of interest, which is then stimulated using surface current. Chronaxie values increase ... Data reported in the literature use either motor response as the physiological threshold in humans or action potential ... Data derived from micro-electrode stimulation and physiological mapping of sensory thalamus are scarce. The two stimulation ...
Seymour, Mona (2019). "Map of North American Veganic Farms". www.arcgis.com. Retrieved 2021-01-04. "2019 Organic Survey". www. ... Animal free agriculture has the potential to prevent illnesses like influenza from spreading. Experts agree that most strains ... and nitrogen from these wastes is converted into ammonia and nitrates which leach into ground and surface water causing ... network organizations as well as certification bodies that certify farms according to the Biocyclic Vegan Standard. There is a ...
... of bodies of water in the Canadian High Arctic to Holocene climate change and to potential paleolake regions on the surface of ... The work is supported by the Ocean Exploration Trust, as part of an initiative of Robert Ballard to explore and map the deep ... Shea, Rachel Hartigan (18 October 2013). "Discoverer of the Titanic Is Mapping Underwater America". National Geographic. ... extreme landscapes like volcanoes and Arctic deserts serve as physical or operational substitutes for various planetary bodies ...
... "build a series of projects that map the surfaces of rocky worlds and explore the atmospheres of planets and small bodies the ... leveraging its advantages against student time constraints and potential bandwidth limitations. Gay's work on Exploring the ... mapping and characterization of surface features using visual data provided by NASA missions. Crater counting is described as " ... "a valuable exercise, but it's hard to automate." Surface features, such as the size and degradation of craters, are identified ...
In addition, it will map the surface to study features that may point to tectonic activity due to a subsurface ocean. Although ... A potential biosignature is a phenomenon that may have been produced by life, but for which alternate abiotic origins may also ... body fossils, casts), biofabrics (including microbial mats), diagnostic organic molecules, isotopic signatures, evidence of ... On Mars, surface oxidants and UV radiation will have altered or destroyed organic molecules at or near the surface. One issue ...
Minimal configuration of body surface potential mapping for discrimination of left versus right dominant frequencies during ... Keywords: atrial fibrillation; body surface potential mapping; dominant frequency; electrocardiography; lead distribution. ... with body surface potential mapping (BSPM) systems. This study quantifies the accuracy of dominant frequency (DF) measurements ... DF activity was analyzed on the surface potentials for the nine leads configurations, and the noninvasive measures were ...
... of the brain causes the spinal cord and peripheral muscles to produce neuroelectrical signals known as motor evoked potentials ... this allows stereotactic mapping of the motor cortex. MEPs are recorded with surface electrodes, which are placed over small ... The hand-held part is freely movable so that it can be placed over any part of the body. The investigator holds the stimulating ... Motor evoked potentials (MEPs) usually are recorded with surface electrodes in target muscles. Coaxial needle electrodes can be ...
Kavuru, Madhav S.; Vesselle, Hubert; Thomas, Cecil W. (1987). Advances in Body Surface Potential Mapping (BSPM) Instrumentation ... It also does not truly represent the center-of-heart potential due to the body parts the signals travel through. Leads I, II ... Electrodes are the actual conductive pads attached to the body surface. Any pair of electrodes can measure the electrical ... Both branches conduct action potentials at about 1 m/s. Interestingly, however, the action potential starts traveling down the ...
Body surface potential mapping, Computational cardiac electrophysiology, Inverse potential mapping, MRI-conditional pacemaker ... MRI can be used in combination with body surface potential mapping (BSPM) in a non-invasive inverse potential mapping (IPM) ... In non-invasive IPM, epicardial potentials are reconstructed from recorded body surface potentials (BSP). In order to ... Non-invasive focus localization, right ventricular epicardial potential mapping in patients with an MRI-conditional pacemaker ...
The map shows the ecological status or potential of surface water bodies based on their quality elements status value. The ... The WISE Water Framework Directive Quality Elements map contains information from the 2nd River Basin Management Plans (RBMPs) ... the surface water bodies (water body category, ecological status or potential and chemical status), the groundwater bodies ( ... The map shows the ecological status or potential of surface water bodies based on their quality elements status value. The ...
2017). Noninvasive personalization of a cardiac electrophysiology model from body surface potential mapping. IEEE Trans. Biomed ... Surface-based fluid cavities and fluid exchanges were used to model blood flow (ABAQUS Analysis Users Guide). ... A pressure load was applied to the LV surface to simulate diastole, whereas the contraction of the LV muscles caused systole. ... This boundary condition prevents rigid body rotation, but allows inflations and contractions of the annulus. The nodes of the ...
Frontiers in non-invasive cardiac mapping: future implications for arrhythmia treatment - Minerva Cardioangiologica 2018 ... Electrocardiographic mapping (ECM) is a noninvasive technique using body surface potentials and CT geometry to reconstruct ... Panoramic mapping of ventricular fibrillation (VF) is helping to develop a better understanding of its physiology, with future ... Frontiers in non-invasive cardiac mapping: future implications for arrhythmia treatment. Antonio FRONTERA 1, 2 ✉, Ghassen ...
Outcome Prediction for Paroxysmal Atrial Fibrillation Using Trajectories of Activation From Body Surface Potential Maps Author( ... Detection of focal source and arrhythmogenic substrate from body surface potentials to guide atrial fibrillation ablation ... In-silico pace-mapping using a detailed whole torso model and implanted electronic device electrograms for more efficient ...
For near-surface anomalies, potential fields are typically measured in traverses or gridded surveys at the surface. For both ... Typically the gradients, as opposed to the actual potential differences are mapped. Equipotential lines (contours with the same ... It is also effective in locating isolated bodies that may be either geological or cultural in origin. Some researchers have ... 4. Spontaneous-Potential (SP):. The spontaneous-potential or self-potential method utilizes two electrodes located on the ...
This technology allows hydrographers to map the velocity profile of water bodies from surface to bottom. During a flood, this ... These are not just pieces of equipment; they are the sentinels that stand between us and potential disaster. Investing in ... The vertical beam on an ADVM sends a series of pulses and waits for a reflection from the waters surface. The instrument ... When rain falls, water runs across the Earths surface-rather than being absorbed-and picks up debris from the fire, resulting ...
BODY SURFACE POTENTIAL MAPPING IN HYPERTENSIVE RAT DURING VENTRICULAR DEPOLARIZATION. Suslonova O.V., Smirnova S.L., ... PARTICULARS OF AN ANATOMICAL STRUCTURE OF ELEMENTS OF MORPHOLOGY OF AN OCCULUSAL SURFACE OF THE LATERAL TEETH ON THE MAXILLA OF ... DEVELOPMENT OF TEACHERS PROFESSIONALISM IN THE GENERAL EDUCATION SYSTEM BY USING EDUCATIONAL POTENTIAL OF THE INFORMAL ...
19] Using vectorcardiograms and body surface potential maps, investigators were able to show that depolarization abnormalities ... and body surface potential maps during ajmaline provocation. J Am Coll Cardiol. 2010 Feb 23. 55(8):789-97. [QxMD MEDLINE Link] ... This is thought to be due to an increased contribution of the transient outward current (Ito) to the action potential waveform ... However, such an examination is necessary to exclude other potential cardiac causes of syncope or cardiac arrest in an ...
Visual Sophistication through Texture Mapping. Physically Derived Shading Models. Beneath the Surface ... Rigid-Body Dynamics. How Rigid-Body Dynamics are Created. Potential Problems. Other Issues ... Lens Mapping for VFX; Native Stereo; Real-Time VFX and Camera Tracking; Shot/Element Pulls and Delivery to VFX; Techvis; VFX ...
This includes the Earth, where oceans and polar ice coverage prevent similar high-resolution mapping of the rocky surfaces ... LRO has provided us the best global mapping of the shape of any planetary body in the Solar System. ... As a capstone to their lessons, the astronauts were tasked with identifying areas of interest for potential landings from a ... lunar surface roughness, and has begun generation of a high-resolution 3D map of the Moon. u003cstrongu003eCredits: NASA/ ...
Figure 2: The active site and map of potential surface. The GA-LS method was adopted to perform the molecular docking. The ... that was generated by resorting to multi body molecular dynamics simulations, was downloading from the PDB bank server [PDB ... We expected potential H-bond acceptor sites formed by the carbonyl groups. We promoted two carbonyl groups in the newly ... The grid maps of docking studies were computed using the AutoGrid4 included in the Autodock4 distribution. Grid center was ...
Water samples are collected in boreholes and surface water bodies in areas surrounding mining areas, and analysed for ... Geotechnical Hazard mapping House affected by the Pahl Fault. Operation of Rock and Soil Mechanics Laboratory. Products. * Maps ... Monitoring and assessment of risk potential of abandoned mines.. Contribution to coastal management, urban and land use ... Contamination mapping and Land Use Planning- Tsumeb. *Findings by the GSN indicated high As and other metals such as Cu, Pb, Cd ...
Map showing distance from site to closest residence or potential future residence. Help identify population potentially ... Locations of major surface water bodies. Understand climatic and geologic conditions. Site boundaries. Fenced areas. Delineate ... Identify conduits for and barriers to potential contaminant transport. *Pinpoint land use near the site (distances to ...
These synergies offer promising potential for multi-sensor analysis of Arctic-Boreal surface water bodies. In total, 3167 km2 ... and our mapped water bodies followed power-law distributions, but only for water bodies greater than 0.34 (±0.13) km2 in area. ... mapping using high-resolution imagery remains the most accurate way to estimate the abundance of small surface water bodies. We ... Detected water body sizes range from 0.00004 km2 (40 m2) to 15 km2. Power-law extrapolations are commonly used to estimate the ...
... surface water bodies, locations where materials are exposed to precipitation, locations where major spills or leaks identified ... a. Site map. The site map shall document:. (1) An outline of the drainage area of each stormwater outfall that are within the ... or maintenance that has a significant effect on the discharge or the potential for the discharge of pollutants to surface ... Flows with a potential for causing erosion shall be identified.. b. Inventory of exposed materials. A list of the industrial ...
High-resolution satellite images reveal 22% as high erosion-prone and 5% as very high. GIS modeling successfully maps soil ... Identify potential soil erosion areas in Mustang, Nepal using remote sensing and GIS techniques. ... and water quality problems in nearby surface water bodies, from the plains to the mountain areas in Nepal. The goal of this ... Sharma, A. (2010) Integrating Terrain and Vegetation Indices for Identifying Potential Soil Erosion Risk Area. GeoSpatial ...
Body surface mapping system (Active Two, MK2, Biosemi, the Netherlands) with 128 electrodes records body surface potentials at ... measurement system is designed to measure potential differences on the human body surface. For body surface mapping ... including body surface potentials mapping, intracardiac electrograms, surface ECG, blood pressure signals, and more. ... Torso geometry reconstruction and body surface electrode localization using three-dimensional photography. J Electrocardiol. ...
... body) growth. Small body size, on the other hand, allows for greater access to benthic shelter and the potential utilization of ... modified snouts that allow for greater feeding efficiency on the surface, or enlarged eyes that promote detection of potential ... www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/marine-ecology ... Different body sizes confer distinct advantages. Large body size is favorable for species that swim in the water column. Large ...
Pepsis elegans could conveniently use the spiders burrow as a nest without having to excavate one from the ground surface and ... Pepsis elegans females from various localities had dried mud on the forewings and body inferring they were underground in moist ... The genus Ummidia and P. elegans have nearly identical geographic location maps and occur in the same habitat. ... Potential host spider for P. elegans may include cork-lid trapdoor spiders in the genus Ummidia Thorell, especially U. audouini ...
Maps of gravity and magnetic basement, deep and near surface structural lineaments were mapped. Euler deconvolution, first and ... Recently we located near the cinder cone "La Polvora" the presence of two intrusive bodies whose trajectory forms a NW ... Title: Investigation with Regard to Mineralogical-Gemological, Geochemical and Mining Potential of Diagenetic Gemmy Opal (Sio2 ... As an economic mining potential, blackish-mottled, gem quality, multi-colored opal (SiO2 + nH2O) (microcrystalline quartz ...
... based on calculating surface maps from pdb models and colouring maps based on charge potentials of each residue. Initial SecM ... The model was rigid-body fit into each cryo-EM map in Chimera and then refined manually (residue by residue) in Coot. The SecM ... Electrostatic potential maps for ribosome exit tunnel, FLN6 NC and FLN5 structures were calculated using Chimera 34, ... The PDB model was rigid body fit into sharpened cryo-EM maps in UCSF Chimera 34 and subsequently refined iteratively using ...
... surface water bodies and water courses.. Fig. 6 Recreation Potential in Poznań ... The Recreation Potential map was cross-tabulated with the Recreation Opportunity map, which includes presence of recreational ... the Poznań City Lab assessed the Recreation Potential in the city. The Recreation Potential map (Fig. 6) takes into account ... Based on the Recreation Opportunity Spectrum map, potential areas for greening under urban regeneration action have been ...
... they can be readily identified with high-resolution torso ECG mapping. ... Identifying patients at risk of such abnormalities by use of body surface electrical measures is controversial. We investigated ... Animals, Arrhythmias, Cardiac, Body Surface Potential Mapping, Electrocardiography, Heart Ventricles, Kinetics, Myocardial ... Identifying patients at risk of such abnormalities by use of body surface electrical measures is controversial. We investigated ...
Potential maps displayed electrical potentials at all locations on the heart surface at any time within the map interval. A ... The mapping process involved the fitting of a multi-electrode vest to capture electrical signals from the body surface of study ... Mean ventricular potential maps. QRS potential propagation according to anatomical regions in patients with CA (A) and controls ... 8 Activation maps captured the time of the steepest slope of each electrical potential measured on the cardiac surface. ...
Working outside of salmonid habitat (see map).. *Returning effluent (water) from the mining activity back to the water body or ... This permit includes the requirements you must follow in order to discharge water to surface water bodies, like lakes or ... Determine if you are within a mining potential use area (see map) ... View the Potential Use Areas Map. *Learn more about what is ... Mining potential use area*. Allowed with NPDES permit and HPA permit. Allowed - HPA permit or Gold and Fish pamphlet coverage. ...

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