We examined whether a magnetic field comparable to one of the fields produced during MRI induced steady-state changes in brain electrical activity while the field was applied (called a presence effect to distinguish it from evoked potentials). The electroencephalogram was measured from standard scalp locations in the presence and absence ...

This paper describes a novel powerful noncontact actuation of a magnetically driven microtool (MMT), achieved by magnetization of the MMT and focusing of the magnetic field in a microfluidic chip for particle sorting. The following are the highlights of this study: (1) an MMT was successfully fabricated from a mixture ...

Functional magnetic resonance imaging (fMRI) was used to investigate the dose-response relationship (sham, 100, 200, 1000 microT) between a pulsed extremely low frequency magnetic field (ELFMF) and acute thermal pain on the dominant right hand. Forty-seven participants were recruited, and pulsed ELFMF was applied through the MRI gradient system using ...

The early history of the principal meeting in the field of biological NMR spectroscopy, the International Conference on Magnetic Resonance in Biological Systems (ICMRBS), is presented from the perspective of one of the founders.

Magnetic interactions in silica coated spherical nanoporous assemblies of CoFe(2)O(4) nanoparticles have been investigated by low temperature field dependent remanent magnetization (M(DCD) and M(IRM)) and magnetization relaxation measurements. The synthesis procedure leads to the formation of spherical aggregates of about 50-60 nm in diameter composed of hexagonal shaped nanocrystals with ...

Magnetic force microscopy (MFM) is a very powerful technique, which can potentially be used to detect and localize the magnetic fields arising from nanoscopic magnetic domains, such as magnetic nanoparticles. However, in order to achieve this, we must be able to use MFM to discriminate between magnetic forces arising from ...

In this study, effect of magnetic field on the activity of activated sludge in wastewater treatment was investigated. During the experiment, biodegradation duration, magnetic density, operating temperature and medium pH value were changed within the ranges from 0 to 60h, 0 to 500.0mT, 10.0 to 50.0 degrees C and 3.0 ...

The use of parahydrogen-induced polarization (PHIP) for signal enhancement in nuclear magnetic resonance spectroscopy (NMR) is well established. Recently, this method has been adopted to increase the sensitivity of magnetic resonance imaging (MRI). The transfer of non-thermal spin hyperpolarization--from parahydrogen to a heteronucleus--provides better contrast, thus enabling new imaging agents. ...

Low-temperature heat capacity and oriented single-crystal field-cooled and zero-field-cooled magnetization data for the single-molecule magnet [Ni(hmp)(dmb)Cl](4) are presented that indicate the presence of ferromagnetic ordering at approximately 300 mK, which has little effect on the magnetization relaxation rates.

This tutorial review summarizes the recent advances on the self assembly of magnetic nanoparticles into one-, two-, and three-dimensional architectures using synthetic polymers and biopolymers. The materials have unique stimuli-responsive behavior that emerge in response to internal and external magnetic fields. For example, magnetic fields can be used to elicit ...

Magnetic materials, such as ferrimagnetic and ferromagnetic nanoparticles and microparticles in the form of ferrofluids, can be advantageously used in micro-electro-mechanical systems (MEMS) and bioMEMS applications, as they possess several unique features that provide solutions for major microfluidic challenges. These materials come with a wide range of sizes, tunable magnetic ...

GoldMag (Fe3O4/Au) nanoparticles have the advantages of both magnetic response in an external magnetic field and the immobilization of molecules on their surface in a single step. The cytotoxicities of GoldMag nanoparticles and GoldMag nanoparticles loaded with doxorubicin (Dox-GoldMag) combined with an external magnetic field were tested in vitro on ...

PURPOSE: To evaluate the effect of 23-sodium ((23)Na) and 17-oxygen ((17)O) magnetic resonance imaging (MRI) at 9.4 (T) on vital signs and cognitive function of the human brain. MATERIALS AND METHODS: Vital sign and cognitive function measurements from healthy volunteers (N = 14) positioned outside and at isocenter of a ...

This paper proposes the possibility of spatially resolved MRI measurements undertaken inside metallic cells. MRI has been rarely usable inside conducting vessels due to the eddy currents in the walls caused by switching magnetic field gradients, which render most advanced MRI pulse sequences impossible. We propose magnetic field gradient waveform ...

Recent interest in the poroelastic behavior of tissues has led to the development of magnetic resonance poroelastography (MRPE) as an alternative to single-phase MR elastographic image reconstruction. In addition to the elastic parameters (i.e., Lamé's constants) commonly associated with magnetic resonance elastography (MRE), MRPE enables estimation of the time-harmonic pore-pressure ...

The diagnosis of MS is based on the revised McDonald criteria and is multidisciplinary. Both clinical and paraclinical measures are included. High-field magnetic resonance imaging (MRI) is becoming increasingly available and it is therefore necessary to clarify possible advantages of high-field MRI in MS. The aim of this paper was ...

Aim To evaluate the magnetic properties of the Ex-PRESS stainless steel glaucoma drainage device during MRI. Design Experimental study. Methods The Ex-PRESS glaucoma drainage device (316L stainless steel) was examined for magnetic field interactions under standard 1.5, 3.0, and 4.7 T MRI scanning protocols. Testing included measurements of translational and rotational ...

This article represents the effects on actin filaments attached to magnetic nanoparticles when exposed to low-intensity magnetic field. In this approach, streptavidin functionalized magnetic nanoparticles were used to demonstrate the alignment of actin filament under external magnetic field of 22mT. To check the directionality of myosin on magnetically aligned actin ...

We investigate the possibility of using magnetorheological polydimethylsiloxane (MR-PDMS) spheres as micro-optical resonators. In particular, the effect of a magnetic field on the whispering gallery modes (WGM) of these resonators is studied. The applied field induces mechanical deformation, causing shifts in the WGM. The microspheres are made of PDMS with ...

This paper proposes a modified Chan-Vese model to segment levator ani muscles from axial magnetic resonance (MR) images. Intensity variances of the foreground and the background are used as the main segmentation clues. As in most cases the boundary of the rectum can be successfully segmented in axial MR images, ...

Magnetic nanoparticles for therapy and diagnosis are at the leading edge of the rapidly developing field of bionanotechnology. In this study, we have theoretically studied motion of magnetic nano- as well as micro-particles in the field of cylindrical Halbach array of permanent magnets. Magnetic flux density was modeled as magnetostatic ...

The magneto resistance (MR) of polyacetylene nanofibers is reviewed in this tutorial review. Earlier MR results on film types of polyacetylene and other conducting polymers are summarized first and then recent progress on the synthesis and characterization of conducting polymer nanofibers and tubes are surveyed. The studies on the dispersion ...

Magnetic polymer particles have been used in a wide variety of applications ranging from targeting and separation to diagnostics and imaging. Current synthesis methods have limited these particles to spherical or deformations of spherical morphologies. In this paper, we report the use of stop flow lithography to produce magnetic hydrogel ...

HYPOTHESIS: Is the human ossicular chain stabile enough to withstand the torque of a Vibrant Soundbridge middle ear hearing implant in the magnetic field of a 1.5 T magnetic resonance imaging (MRI) system? BACKGROUND: The Vibrant Soundbridge is a semi-implantable hearing device in which a tiny electromechanical transducer, called floating ...

BACKGROUND AND STUDY AIMS: The use of magnetic fields to control operative devices has been recently described in endoluminal and transluminal surgical applications. The exponential decrease of magnetic field strength with distance has major implications for precision of the remote control. We aimed to assess the feasibility and functionality of ...

We describe and demonstrate a system to generate hyperpolarized water in the 0.35 T fringe field of a clinical 1.5 T whole-body magnetic resonance imaging (MRI) magnet. Once generated, the hyperpolarized water is quickly and continuously transferred from the 0.35 T fringe to the 1.5 T center field of the ...

ECGs are currently acquired during magnetic resonance examinations. This "hostile" environment highly distorts ECG signals, due to the high-static magnetic field, RF pulses and fast switching magnetic gradients. Specific signal processing is then required since the ECG signal is used for image synchronization with heart activity (or triggering) and for ...

In migratory passerine birds, strong magnetic pulses are thought to be diagnostic of the remagnetization of iron minerals in a putative sensory system contained in the beak. Previous evidence suggests that while such a magnetic pulse affects the orientation of migratory birds in orientation cages, no effect was present when ...

Ballistic quantum wires are exposed to longitudinal profiles of perpendicular magnetic fields composed of a spike and a homogeneous part. An asymmetric magnetoconductance peak as a function of the homogeneous magnetic field is found, comprising quantized conductance steps in the interval where the homogeneous magnetic field and the magnetic barrier ...

BACKGROUND: Awake craniotomy and electrophysiologic mapping (EPM) is an established technique to facilitate the resection of near eloquent cortex. Intraoperative magnetic resonance imaging (iMRI) is increasingly used to aid in the resection of intracranial lesions. Standard draping protocols in high-field iMRI units make awake craniotomies challenging, and only two groups ...

PURPOSE: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the ...

PURPOSE: To assess potential cognitive deficits under the influence of static magnetic fields at various field strengths some studies already exist. These studies were not focused on attention as the most vulnerable cognitive function. Additionally, mostly no magnetic resonance imaging (MRI) sequences were performed. MATERIALS AND METHODS: In all, 25 ...

PURPOSE: To investigate residual magnetization at different locations in the MRI suite at several time points prior, during and after field-rampdown with the goal to determine if the MRI suites could be reused in a clinical environment after the field-rampdown of MR scanners of different field strengths. MATERIALS AND METHODS: ...

The increase in the use of magnetic resonance imaging (MRI) for diagnostic use in companion animals has increased the demand for anesthesia support in a strong magnetic environment. In many instances, this may necessitate anesthesia being provided by individuals that are unfamiliar with MRI and the hazards associated with it. ...

Functional MRI has become an important tool of researchers and clinicians who seek to understand patterns of neuronal activation that accompany sensory and cognitive processes. However, the interpretation of fMRI images rests on assumptions about the relationship between neuronal firing and hemodynamic response that are not firmly grounded in rigorous ...

The purpose of this study was to provide a detailed anatomical description of the soft-tissue structures of the head of normal rabbits using low-field magnetic resonance imaging (MRI). The cadaver heads of six domestic rabbits and one dwarf rabbit were used to perform transverse, sagittal and dorsal 2.5-mm-thick T1-weighted images. ...

Artifacts in MR(Magnetic Resonance) images of oral cavity produced from non-magnetic metal restorations was verified by measuring the image of index finger and a cylinder of fat test piece with a type 4 gold alloy ring using a compact MRI equipment. In the images of finger, portion around the ring ...

The viability and a number of morphological properties of in situ astrocytes of rat spinal cord cultures including changes in surface area and migration of both cell body and nucleus were investigated at magnetic field intensities comparable to those currently used for magnetic resonance imaging. Viability of rat spinal astrocytes ...

Although nuclear magnetic resonance in low fields around or below the Earth's magnetic field is almost as old as nuclear magnetic resonance itself, the recent years have experienced a revival of this technique that is opposed to the common trend towards higher and higher fields. The background of this development ...

We report a novel aspect of the competition and coexistence between magnetism and superconductivity in the high-T(c) cuprate La(2-x)Sr(x)CuO4 (La214). With a modest magnetic field applied H parallel c axis, we monitored the infrared signature of pair tunneling between the CuO2 planes and discovered the complete suppression of interlayer coupling ...

Experimental data up to 7.0 T show that the blood oxygenation level-dependent (BOLD) signal of functional magnetic resonance imaging (fMRI) increases with higher magnetic field strength. Although several studies at 11.7 T report higher BOLD signal compared with studies at 7.0 T, no direct comparison at these two field strengths ...

Recent developments in high-field magnetic resonance imaging technology have led to improved contrast and resolution and are opening up new possibilities for the study of human brain anatomy. In particular, techniques sensitized to magnetic susceptibility contrast provide particular advantages at high field that have allowed visualization of brain structures that ...

Starting from general results of magnetostatics, we give fundamental considerations on the design and characterization of permanent magnets for NMR based on harmonic analysis and symmetry. We then propose a simple geometry that takes advantage of some of these considerations and discuss the practical aspects of the assembly of a ...

We present a solid state magnetic field imaging technique using a two-dimensional array of spins in diamond. The magnetic sensing spin array is made of nitrogen vacancy (NV) centers created at shallow depths. Their optical response is used for measuring external magnetic fields in close proximity. Optically detected magnetic resonance ...

The field of neuroimaging witnessed remarkable progress in the post-World War II era, resulting in tremendous benefits for healthcare today. One such important milestone was the development of the computerized axial tomography (CAT) scan. This state of the art technique has paved the way for modern diagnostic imaging like magnetic ...

PURPOSE: One of the recently published concepts that combine the soft-tissue imaging capabilities of MRI with external beam radiotherapy involves the rigid coupling of a linac with a rotating biplanar low-field MR imaging system. While such a system would prevent possible image distortion resulting from relative motion between the magnet ...

The viability of the microbes Saccharomyces cerevisiae, Bacillus circulans, Escherichia coli, Micrococcus luteus, Pseudomonas fluorescens, Salmonella enteritidis, Serratia marcescens, and Staphylococcus aureus was tested under static magnetic field exposure up to 24 h in either a homogeneous (159.2 +/- 13.4 mT) or three types of inhomogeneous static magnetic fields: (i) ...

We have developed and tested two types of novel dielectric resonators for simultaneous recording of electron paramagnetic resonance (EPR) spectra from two to four samples. The resonator of the first type contains two holes, and the other resonator contains four holes for introduction of the samples. Also, the resonator structure ...

To map the distribution of the magnetic force induced in the human head during magnetic resonance imaging (MRI) at 4 T for a large group of healthy volunteers. The magnetic field distribution in the head of 100 men and 18 women was mapped using phase mapping techniques. Statistical parametric mapping ...

AIMS: The number of low-field (<0.5 T) magnetic resonance (MR) scanners installed worldwide is increasing due to a favourable cost and safety profile and improved patient comfort using an open-scanner design. Therefore, the aim of our study was to evaluate a strategy for the safe performance of magnetic resonance imaging ...