Magneto-Rheological (MR) fluid is a class of controllable smart material whose rheological properties may be rapidly varied by the application of a magnetic field. In this paper we focus on our MR fluid based haptic system providing accurate haptic feedback for needle insertion and syringe injection. We use the essential ...

In order to improve the spatial resolution achieved by magnetic force microscopy (MFM) technique and its derivatives, we employ here advanced MFM tips fabricated by means of focused ion beam (FIB) milling. The magnetic coating applied on these tips is a CoCr film of 10 nm thickness. The MFM measurements ...

While the role of magnetic cues for compass orientation has been confirmed in numerous animals, the mechanism of detection is still debated. Two hypotheses have been proposed, one based on a light dependent mechanism, apparently used by birds and another based on a "compass organelle" containing the iron oxide particles ...

Objective: Magnets are purported to aid wound healing despite a paucity of scientific evidence. The purpose of this study was to evaluate the effect of static magnetic fields on cutaneous wound healing in an animal model. The literature was reviewed to explore the historical and scientific basis of magnet therapy ...

With acceptance and utilization of chemical pesticides declining, some vegetable producers are turning to alternative methods to manage plant health issues. Compost tea (CT) has provided control of some foliar pathogens and may provide benefits beyond disease suppression. Despite an increasing body of popular and scientific literature focusing on CT ...

BACKGROUND: Magnetic retraction has potential advantages over existing direct physical retraction means (e.g., forceps) in terms of providing complete atraumatic retraction, avoiding tumour cell exfoliation as well as offering the possibility of noncontact retraction. This paper describes a pilot study of surface magnetic retraction of the gastric mucosa to facilitate ...

We investigate how an amoeba mechanically moves its own center of gravity using the model organism Physarum plasmodium. Time-dependent velocity fields of protoplasmic streaming over the whole plasmodia were measured with a particle image velocimetry program developed for this work. Combining these data with measurements of the simultaneous movements of ...

(1) The waterproof outer layer protecting some transdermal patches is composed of aluminium. This creates a risk of burns, especially when the patient is exposed to electric shocks or intense magnetic fields. (2) External electrical shocks delivered by a defibrillator for example can create electrical arcing between the electrode and ...

BACKGROUND: This paper presents a magnetic resonance (MR) compatible joystick for controlling a surgical robot arm. The surgical robot can be used to assist the surgeon in high precision neurosurgery tasks. Conventional joysticks cannot be used in magnetic resonance imaging (MRI) environments, because they generally contain ferromagnetic materials such as ...

Subpicosecond magnetization reversal is experimentally demonstrated by ultrafast heating of a ferrimagnet across its compensation points, under an applied magnetic field. While the reversal is initiated by crossing the magnetization compensation temperature, the short reversal time is related to the angular momentum compensation, where the dynamics of the system is ...

A study of the effects of small-angle specimen tilt on high-resolution annular dark field images was carried out for scanning transmission electron microscopes with uncorrected and aberration-corrected probes using multislice simulations. The results indicate that even in the cases of specimen tilts of the order of 1 degree a factor ...

PURPOSE: To determine if magnetic field exposure close to two clinical 1.5 T magnetic resonance imaging (MRI) scanners during image acquisition and when moving in the spatially-varying static magnetic field is compliant with European Union (EU) Directive 2004/40/EC (the Directive). MATERIALS AND METHODS: Using commercially available equipment we measured the ...

PURPOSE: To map the induced magnetic field gradients and estimate the magnetic force in the human head during magnetic resonance imaging at 4 Tesla (T). MATERIALS AND METHODS: The magnetic field distribution in the human head was measured using two gradient-echo experiments with different echo times. The phase of the ...

PURPOSE: To assess whether exposure to a 9.4 T static magnetic field during sodium imaging at 105.92 MHz affects human vital signs and cognitive function. MATERIALS AND METHODS: Measurements of human vital signs and cognitive ability made before and after exposure to a 9.4 T MR scanner and a mock ...

Magnetic micromanipulation using magnetic tweezers is a versatile biophysical technique and has been used for single-molecule unfolding, rheology measurements, and studies of force-regulated processes in living cells. This article describes an inexpensive magnetic tweezer setup for the application of precisely controlled forces up to 100 nN onto 5 microm magnetic ...

PURPOSE: To assess exposure of MR staff to static and time-varying gradient magnetic fields by direct measurement and questionnaire and to compare these to the action values and exposure limits stated in published guidance. MATERIALS AND METHODS: Instantaneous and time-averaged exposure to static magnetic fields were measured on clinical and ...

This paper describes a technique to control the navigation of traditional wireless endoscopic capsules and reports preliminary proof-of-concept investigations. These capsules are used for noninvasive explorations of the digestive tube. At present, their motion cannot be controlled and they proceed by means of the visceral peristalsis. In order to enable ...

The V(TCNE){x}, x approximately 2 is an organic-based amorphous ferrimagnet, whose magnetic behavior is significantly affected in the low field regime by the random magnetic anisotropy. It was determined that this material has thermally reversible persistent change in both magnetization and conductivity driven by the optical excitation. Here, we report ...

A Dove prism and an anamorphic prism pair are investigated in negative index imaging systems. An equilateral triangular prism with refractive index of -1 operates as a negative index Dove prism that inverts as well as images the incident field. A negative index anamorphic prism pair acts as a negative ...

We report a detection method for C-reactive protein (CRP) based on competitive immunoassay using magnetic nanoparticles under magnetic fields. Functional magnetic nanoparticles were prepared and conjugated with anti-CRP for immunoassay. Magnetic nanoparticles labeled with anti-CRP were flowed through a separation channel to form depositions for selective capture of CRP under ...

The construction and achievement of the first signal on a cryogenic Fourier-transform ion cyclotron resonance mass spectrometer (FTICR-MS) are reported here, demonstrating proof-of-concept of this new instrument design. Building the FTICR cell into the cold bore of a superconducting magnet provided advantages over conventional warm bore design. At 4.2 K, ...

Single-phased powder BiCrO(3) sample was prepared at 6 GPa and 1653 K. Its magnetic properties were investigated by dc/ac magnetization, magnetic relaxation, and specific heat measurements. Four anomalies of magnetic origin were found near 40, 75, 109, and 111 K. The long-range antiferromagnetic order with weak ferromagnetism occurs at T(N) ...

OBJECTIVES: Analysis of form and function relationships with tumour-mediated dislocations and deformations of the optic chiasm. MATERIALS AND METHODS: Results of magnetic resonance tomography and two forms of quantitative, computerized perimetry were contrasted in 31 patients with pituitary adenomata impinging on the chiasm, prior to treatment. RESULTS: Perimetric abnormalities ranged ...

The focus of this report was to test the performance of a novel piezoelectric motor under high magnetic field strength conditions and to investigate its potential applications in small animal magnetic resonance imaging (MRI). The device is made entirely of nonferrous materials and consists of four piezoelectric ceramic plates connected ...

OBJECTIVE: To assess how magnetic fields (MFs), with or without concurrent radio frequency (RF), influence chondrocytes and knee joint repair, we applied an MF strength via magnetic resonance imaging (MRI) slightly greater than the frequently used dosage in the clinics and examined the effects of these treatments in vitro on ...

A magnetically actuated MEMS scanner with a microfabricated ferromagnetic nickel platform and thermosetting polydimethylsiloxane (PDMS) microlens is demonstrated. The device is driven by an external AC magnetic field, eliminating chip circuitry and thermal deformation from joule heating. The resonant frequency of 215.2 Hz and scanning angle of 23 of the ...

AIMS: To examine usage of the first CT scanner installed in a UK field hospital, BMH Shaibah, over a 13 month period. METHODS: All request forms and reports for the first 100 studies were analysed retrospectively. RESULTS: An average of 7.7 scans per month was performed. Trauma was the most ...

By applying dephasing gradients, local magnetic field inhomogeneitiescan selectively visualized with positive contrast, such as those created by magnetically labeled cells. This is known as "white-marker imaging." In white-marker imaging, subvoxel signal variations are also visualized as a result of partial volume (PV) effects and may compromise the identification of ...

This observational field study used intermittent still photography to examine the distribution of motor laterality in images of two African grazing quadruped species: plains zebras (Equus burchellii) and impalas (Aepyceros melampus). Zebra images (n=708) had a laterality index of -6.21 and a Z-score of -1.65 (p=.098). Impala images (n=318) had ...

Magnetic elastica with spontaneous magnetization and superparamagnetic properties are considered. Obtained solutions illustrate the characteristic transformations of their shapes as spontaneous magnetization increases. Solutions are selected on the basis of the stability analysis and results of numerical simulations. A different mechanism of the magnetic relaxation in suspension of ferromagnetic filaments ...

The approach to the diagnosis and management of glaucoma has undergone considerable changes in recent years. Current concepts of glaucoma diagnosis focus on structural assessment and structure-function correlation, and relies less on the finding of visual field abnormalities. In turn, contemporary approaches to management have also changed and revolve around ...

The high frequency of the radiofrequency (RF) fields used in high field magnetic resonance imaging (MRI) results in electromagnetic field variations that can cause local regions to have a large specific absorption rate (SAR) and/or a low excitation. In this study, we evaluated the use of a B1 shimming technique ...

A portable separator has been developed to quantitatively separate blood-borne magnetic spheres in potentially high-flow regimes for the human detoxification purpose. In the separator design, an array of biocompatible capillary tubing and magnetizable wires is immersed in an external magnetic field that is generated by two permanent magnets. The wires ...

Although the focus of attention on data degradation during simultaneous MRI/EEG recording has to date largely been upon EEG artefacts, the presence of the conducting wires and electrodes of the EEG recording system also causes some degradation of MRI data quality. This may result from magnetic susceptibility effects which lead ...

The training effect and asymmetry in exchange-coupled polycrystalline CoO/Co bilayers with in-plane magnetization has been investigated. This system is selected for its large training effect and initial asymmetry of the magnetic hysteresis after field cooling, which is removed after training. Applying an in-plane magnetic field perpendicular to the cooling field ...

In this paper we present electromagnetic (EM) analysis of the unloaded slotted-tube resonator (STR) with a circular cross section, using the finite element method (FEM) and method of moments (MoM) in two dimensions. This analysis allows the determination of the primary parameters: [L] and [C] matrices, optimization of the field ...

This article illustrates changes in the underlying physics concepts related to increasing the main magnetic field from 1.5T to 3T. The effects of these changes on tissue constants and practical hardware limitations is discussed as they affect scan time, quality, and contrast. Changes in susceptibility artifacts, chemical shift artifacts, and ...

Soon after its introduction in 1991, MR cholangiopancreatography has become an established diagnostic tool for the evaluation of the pancreaticobiliary ductal system at a field strength of 1.5T. It remains unclear whether MR cholangiopancreatography performed at 3T will benefit from the higher magnetic field strength or whether a field strength ...

BACKGROUND: The recent use of high and ultra-high magnetic field (MF) systems (3.0 T and above) have raised concerns about biologic effects and safety. Sensory symptoms (magnetophosphenes, dizziness/vertigo, headaches, metallic taste, pain changes, and cognitive effects) have been reported. We monitored 1023 consecutive outpatients undergoing MRI after recent introduction of ...

The effects of a magnetic force on magnetic particles linked by cysteamine to a silver colloid plate were analyzed with surface-enhanced Raman scattering spectroscopy. Cysteamine molecules were stretched by a force exerted on the magnetic particles with the external magnetic field gradients generated by two Nd-Fe-B magnets. The spectra showed ...

Scanning nonlinear magnetic microscopy (SNMM) is introduced as a new microscopic technique for measurement of the distribution of magnetization. The technique is based on the detection of inductance variation in a magnetic material under application of an external alternating magnetic field. The measured inductance thus reflects the nonlinear magnetic response ...

Large orthopedic external fixation clamps and related components were evaluated for force, torque, and heating response when subjected to the strong electromagnetic fields of magnetic-resonance (MR) imaging devices. Forces induced by a 3-Tesla (T) MR scanner were compiled for newly designed nonmagnetic clamps and older clamps that contained ferromagnetic components. ...

A 33-year-old man reported an 18 months history of a progressive right eyelid swelling, a sensation of eye pain and headaches. He noted a visual discomfort. Physical examination showed right eyelid edema, without skin lesion. The patient's acuity was unchanged from the baseline; neither exophthalmia nor deficit in the visual ...

This paper reports on the manipulation of magnetic nanoparticles between microfluidic channels by the application of an external magnet. Two orthogonal channels were prepared using standard PDMS techniques with pressure-driven flow used to deliver the mobile phase. To study the ability to control magnetic nanoparticles within micrometer-sized channels, Fe2O3, MnFe2O4, ...

Magnetic sponge-like hydrogels (ferrosponges) were fabricated by using an in-situ synthesis of magnetic nanoparticles (MNPs) in the presence of various concentrations of gelatin. The resulting ferrosponges show an interconnected nanopore structure which serves as a reservoir to accommodate therapeutic drugs and the nanoporous networks demonstrate magnetic sensitive behavior under the ...

The ThinPrep Imaging System (TIS) is an automated system that assists cytotechnologists in the primary screening of ThinPrep liquid based cervical samples. Between June 1, 2004, and April 1, 2005, four experienced cytotechnologists participated in the study in which the duration of the screening procedure was timed for each of ...

The aim of this study was to investigate the effects of a high-strength magnetic field produced by a magnetic resonance imaging (MRI) apparatus on oxidative stress. The effects of a 1.5 T static magnetic field on the total antioxidant capacity (TAC), total oxidant status (TOS) and oxidative stress index (OSI) ...

A new technique for measurement of magnetic properties of materials is demonstrated. It can be used for the measurement of thin magnetic films during their chemical modification. The resonance frequency of a quartz crystal microbalance (QCM) with conducting polymer (polyaniline) suspension in poly(ethylene glycol) was observed to increase with increasing ...

Perineural spread is a common growth pattern of head and neck malignancies. Recognizing this pattern by imaging is important for two reasons: 1) it may be the only evidence of malignancy; and 2) its presence in conjunction with a mass converts management from surgical resection to radiation or chemotherapy. High ...

We study a nonlinear quenching of turbulent magnetic diffusion and effective drift velocity of large-scale magnetic field in a developed two-dimensional MHD turbulence at large magnetic Reynolds numbers. We show that transport of the mean-square magnetic potential strongly changes quenching of turbulent magnetic diffusion. In particularly, the catastrophic quenching of ...