A "parallel current constraint" is derived, that in combination with the Poisson equation allows one to select admissible equilibria of non-neutral plasmas in a Malmberg-Penning trap in the presence of a nonuniform and nonaxisymmetric magnetic field. Asymmetry-induced currents (analogous to the Pfirsch-Schlüter currents in Tokamaks) appearing in a non-neutral plasma ...

We report high-field magnetization and magnetostriction measurements on the rare-earth-metal tetraboride TbB4, in which the Tb moments form a Shastry-Sutherland lattice in the tetragonal basal plane. A number of magnetization plateaus appear when the magnetic field is perpendicular to the magnetic easy plane. We propose that the magnetization plateaus arise ...

We demonstrate a technique for imaging magnetic fields using velocity-selective two-photon resonances in a cold atom cloud. Freely expanding (85)Rb atoms released from a magneto-optical trap are exposed to a brief (approximately 1 ms), off-resonant, retro-reflected laser pulse in a lin-perp-lin configuration. Two-photon resonance between magnetic sublevels occurs only for ...

In this study we report on magnetic orientation of human sperms. Samples were taken from 17 donors. Normal human sperms became oriented with their long axis perpendicular to the magnetic field (1 T maximum). Total orientation was achieved with magnetic field of about 1 T, while for abnormal sperms the ...

This review article is a description of the present status of magnetic drug delivery systems (DDS). These are colloidal dispersions of composite nanoparticles consisting of a (polymeric or inorganic) biocompatible matrix and magnetic units, and designed to load and release therapeutic drugs. The matrix, together perhaps with adsorbed polymers or ...

An investigation of the magnetic properties of the cobalt(II) citrate cubane [C(NH 2) 3] 8{Co 4(cit) 4}.4H 2O reveals that the cluster is a new cobalt(II) single-molecule magnet, with an energy barrier to reorientation of the magnetization, Delta E/ k B = 21 K, and tau 0 = 8 x ...

MR experiments frequently rely on signal encoding by the application of magnetic fields that vary in both space and time. The accurate interpretation of the resulting signals often requires knowledge of the exact spatiotemporal field evolution during the experiment. To better fulfill this need, a new approach is presented that ...

In this work the 4-(trans- 4'-n -hexylcyclohexyl)-isothiocyanatobenzene (6CHBT) liquid crystal was doped with differently shaped magnetite nanoparticles. The structural changes were observed by capacitance measurements and showed significant influence of the shape and size of the magnetic particles on the magnetic Fréedericksz transition. For the volume concentration phi= 2 x ...

An isolated swine heart ventricle perfusion model was developed and used under physiologically relevant conditions to study implant assisted-magnetic drug targeting (IA-MDT). A stent coil was fabricated from a ferromagnetic SS 430 wire and used to capture 100-nm diameter magnetite particles that mimicked magnetic drug carrier particles (MDCPs). Four key ...

We present time-resolved x-ray images with 30 nm spatial and 70 ps temporal resolution, which reveal details of the spatially resolved magnetization evolution in nanoscale samples of various dimensions during reversible spin-torque switching processes. Our data in conjunction with micromagnetic simulations suggest a simple unified picture of magnetic switching based ...

Experimental investigation of reconnection in magnetized plasmas relies on accurate characterization of the evolving magnetic fields. In experimental configurations where the plasma dynamics are reproducible, magnetic data can be collected in multiple discharges and combined to provide spatially resolved profiles of the plasma dynamics. However, in experiments on spontaneous magnetic ...

We have studied the magnetic switching behavior of thin elliptical permalloy films with structural defects by micromagnetic simulations. The nonmagnetic void was found to tend to pin the adjacent magnetic moment, which alters the local equilibrium magnetization patterns and modifies the switching behavior of magnetization. In particular, for the case ...

Based on the elements that magnetic nanoparticles could heat in an alternating magnetic field, magnetic fluid hyperthermia occurred to inhibit tumor growth in vivo. However, biocompatibility of those fluids as well as the fluid-body interaction remains unclear. In this article, acute toxicity and irritation of the water-based dextran-coated magnetic fluid ...

Since its approval by the FDA in 2000, brain MR imaging at 3.0 T has been increasingly used in clinical practice. Theoretically, the signal-to-noise ratio (SNR) of a 3T MR scanner will be double that of a 1.5 T scanner. However, the relationship between the magnetic field used and the ...

Spiral scanning is a promising MRI method, but one limitation is that off-resonance effects can cause image blurring. Most current off-resonance correction methods for spiral imaging require an accurate field map, which is difficult to obtain in many applications. Automatic methods can perform off-resonance correction without acquiring a field map. ...

OBJECTIVE: To objectively evaluate workers' sensory symptoms and vestibular function after exposure to a strong, new generation 9.4-T Magnetic Resonance Imaging (MRI) scanner. METHOD: Six MRI employees underwent standardized electronystagmographic evaluation, postural testing, and caloric function at baseline evaluation, 30 minutes postexposure to 9.4 T static field and at a ...

Magnetoacoustic tomography with magnetic induction (MAT-MI) is a technique for imaging electrical conductivity in tissue. A time-varying magnetic field induces currents that interact with a static magnetic field to produce a Lorentz force, initiating ultrasonic waves. The goal of this communication is to examine the effect of anisotropy during MAT-MI.

Interventional, "loopless antenna" MRI detectors are currently limited to 1.5 T. This study investigates whether loopless antennae offer signal-to-noise ratio (SNR) and field-of-view (FOV) advantages at higher fields, and whether device heating can be controlled within safe limits. The absolute SNR performance of loopless antennae from 0.5 to 5 T ...

We have demonstrated the capability of scanning magnetoresistance microscope (SMRM) to be used for quantitative current measurements. The SMRM is a magnetic microscope that is based on an atomic force microscope (AFM) and simultaneously measures the localized surface magnetic field distribution and surface topography. The proposed SMRM employs an in-house ...

This is the second part of a two-part series on the clinical applications of high-field-strength (3.0-T) magnetic resonance (MR) imaging and spectroscopy. In this part, the current level of evidence regarding the use of higher magnetic field strengths for cardiac imaging techniques (including the assessment of cardiac anatomy and function), ...

We present a simple modification for thermoelectrically cooled photomultiplier tube (PMT) assemblies that eliminates the magnetic interference between the peltier element and the PMT. An active compensation is accomplished by forming current loops of the wires of the peltier element and placing them in such a way that they eliminate ...

There are concerns about workers repeatedly exposed to magnetic fields exceeding regulatory limits with respect to modern magnetic resonance imaging (MRI). As a result, there is need for an ambulatory magnetic field dosimeter capable of measuring these fields in and around an MRI scanner in order to evaluate the regulatory ...

Transformer stations in apartment buildings may offer a possibility to conduct epidemiological studies that involve high exposure to extremely low frequency magnetic fields (MF), avoid selection bias and minimize confounding factors. To validate exposure assessment based on transformer stations, measurements were performed in thirty buildings in three Finnish cities. In ...

We suggest, based on the principle of causality and for a material exhibiting adjacent absorptive and gain resonances, that there can be an intervening frequency where perfect imaging is in theory possible. At this frequency, both the dielectric constant and the permeability are negative, leading to a negative refractive index, ...

BACKGROUND: Commercial transcranial magnetic stimulators are massive and may be difficult to transport for lecture and teaching purposes OBJECTIVE: To design and construct a portable, battery-powered magnetic stimulator of the lowest possible mass for use in demonstrations and simple measurements RESULTS: The functioning battery-powered single-pulse system is relatively inexpensive, weighs ...

Electrogastrograms (EGGs) produced from gastric electrical activity (GEA) are used as a non-invasive method to aid in the assessment of a subject's gastric condition. It has been documented that recordings of the magnetic activity generated from GEA are more reliable. Typically, with magnetic measurements of GEA, only activity perpendicular to ...

The magnetic method has been previously utilized to concentrate Plasmodium-infected erythrocytes without any significant influence on the viability of the parasite. We attempted, in this study, to concentrate and synchronize cultivated P. falciparum via the magnetic method. The results of this study showed that the magnetic method effectively synchronized and ...

An increasing number of magnetic resonance whole-body units operating at field strengths of 3T and beyond are currently installed in research institutions as well as clinical facilities. This review wants to describe the changes in physical properties at higher field strength and the resulting implications for clinical and experimental examinations ...

In the year 2002, magnetic field strength of more than 2 T was cleared for clinical patient care. Since then, an increasing number of magnetic resonance (MR) systems operating at a field strength of 3.0 T (and higher) have been installed worldwide. This article is the first of a two-part ...

Cardiac magnetic resonance imaging (CMRI) at high magnetic field (3 Tesla) is rapidly evolving with many promising results. However, the challenges of field inhomogeneities and specific absorption rate limitations need to be addressed before reaping the benefits of high magnetic field for CMRI. This review focuses on the methods to ...

Toward realizing the performance of functional and versatile dental magnetic attachments in the third generation required for individual prosthesis, it is important to control retentive characteristics of the attachments. For this purpose, three new types of magnetic attachment, i.e., split-pole type with a slant magnetization, modified split-pole type, and cylinder ...

Herein, we describe the presenting symptoms, history, ophthalmic examination, visual fields and brain magnetic resonance imaging of a patient who developed left homonymous hemianopia due to right occipital lobe hemorrhage after ingestion of sildenafil citrate (Novagra Forte). To the best of our knowledge, association of homonymous hemianopia with sildenafil usage ...

We elucidate a mechanism for obtaining polar behavior in magnetic perovskites based on A-site disorder and demonstrate this mechanism by density functional calculations for the double perovskite (La,Lu)MnNiO6 with Lu concentrations at and below 50%. We show that this material combines polar behavior and ferromagnetism. The mechanism is quite general ...

The characteristics of the phase retardations and the invariability against the incident angles are investigated when light enters the rectangular holes with different sizes perforated on metallic film. A kind of metallic structure with a great potential in imaging is brought forward. The finite difference time domain (FDTD) method and ...

We report that organic semiconductors such as alpha-sexithiophene (alpha-6T) have magnetoresistance (MR) with unexpected sign changes; depending on applied voltage, temperature, and layer thickness, the resistance may either increase or decrease upon application of a small magnetic field (<100 mT). We propose that MR and the inversion of MR are ...

Patent literature describes "conditioning" techniques which employ organic vapours to recrystallise amorphous regions in micronised particles, with the aim of improving their processability and physico-chemical stability. This report describes a preliminary study investigating the efficacy of PhaseImaging atomic force microscopy (AFM) for the investigation of such processes. AFM phase images ...

Surface based geometries of microfabricated wires or patterned magnetic films can be used to magnetically trap and manipulate ultracold neutral atoms or Bose-Einstein condensates. We investigate the magnetic properties of such atom chips using a scanning magnetoresistive (MR) microscope with high spatial resolution and high field sensitivity. By comparing MR ...

Magnetic nanoparticles, which exhibit a variety of unique magnetic phenomena that are drastically different from those of their bulk counterparts, are garnering significant interest since these properties can be advantageous for utilization in a variety of applications ranging from storage media for magnetic memory devices to probes and vectors in ...

The use of magnetic force microscopy (MFM) to detect probe-sample interactions from superparamagnetic nanoparticles in vitro in ambient atmospheric conditions is reported here. By using both magnetic and nonmagnetic probes in dynamic lift-mode imaging and by controlling the direction and magnitude of the external magnetic field applied to the samples, ...

In this paper, a method is proposed for detecting blood vessels in pathological retina images. In the proposed method, blood vessel-like objects are extracted using the Laplacian operator and noisy objects are pruned according to the centerlines, which are detected using the normalized gradient vector field. The method has been ...

For the first time in nuclear magnetic resonance (NMR) magnet development, a magnet configuration comprising an insert wound with high-temperature superconductor (HTS) and a background-field magnet wound with low-temperature superconductor (LTS) has been proven viable for NMR magnets. This new LTS/HTS magnet configuration opens the way for development of 1 ...

Several institutes are currently working on the development of a radiotherapy treatment system with online MR imaging (MRI) modality. The main difference between their designs is the magnetic field strength of the MRI system. While we have chosen a 1.5 Tesla (T) magnetic field strength, the Cross Cancer Institute in ...

Based on measurements of soft x-ray magnetic diffraction under in situ applied electric field, we report on significant manipulation and exciting of commensurate magnetic order in multiferroic ErMn2O5. The induced magnetic scattering intensity arises at the commensurate magnetic Bragg position whereas the initial magnetic signal almost persists. We demonstrate the ...

BACKGROUND: Until very recently mantle field radiotherapy remained the gold standard for the treatment of favorable early-stage Hodgkin's lymphoma. The classic mantle includes all the major lymph nodes above the diaphragm and extends from the inferior portion of the mandible to the level of the insertion of the diaphragm. AIMS: ...

Segmentation of fat suppressed dynamic contrast enhanced MRI (DCE-MRI) image data can pose significant problems because of the inherently poor signal-to-noise ratio (SNR) and intensity variations due to the bias field. Segmentation methods such as balloon snakes, while able to operate in a poor SNR environment, are sensitive to variations ...

Permanent magnets may interfere with the function of cardiac pacemakers and implantable cardioverter-defibrillators (ICDs). Neodymium-iron-boron (NdFeB) magnets have become widely available in recent years and are incorporated in various articles of daily life. We conducted an in-vitro study to evaluate the ability of NdFeB magnets for home and office use ...

The first vertical compact torus (CT) injection experiment has been performed in the Saskatchewan Torus Modified (STOR-M) tokamak [Nucl. Fusion 46, 104 (2006)]. To increase the kinetic energy density of the injected CTs for deeper penetration, the University of Saskatchewan Compact Torus Injector (USCTI) was further modified by attaching a ...

A 27-year-old male presented with recurrent abdominal pain and high volume hematochezia despite undergoing extensive testing and a right hemicolectomy 3 years prior for a linear bleeding ulceration in the ascending colon. Studies at the University of Michigan included esophagogastroduodenoscopy (EGD), colonoscopy and video capsule endoscopy (VCE), revealing an arteriovenous ...

We developed an original dielectric-equivalent gel (Japanese Patent Application ID: P2004-236876A, February 6, 2003) pad that could improve inhomogeneous images caused primarily by B(1) homogeneity on a high-tesla magnetic resonance (MR) system. Made easily from various ingredients, our gel could reduce interference from radiofrequency waves at an object's surface and ...

We report a case of acute appendagitis in a patient who presented initially with typical features of acute appendicitis. The diagnosis of acute appendagitis was made on pathognomonic signs on computed tomography (CT) scan. Abdominal pain is a common surgical emergency. CT is not always done if there are clear ...