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Edge Phantom Measures Sharpness of X-Ray Detectors

The corrected digital image can be used to enable computer-assisted diagnosis.Digital radiography makes use of Xray detectors that yield a radiographic image of the object or patient between the X-ray source and the detector. Tools have been developed to assess the image quality characteristics of radiation images. One tool is an edge phantom, placed between source and detector, to assess the sharpness of the radiation image obtained. The edge-like, spatial step-response of the system resulting from a sudden change in irradiation level, invoked by the phantom, can be used to calculate the modulation transfer function (MTF) in a particular direction. In this way, the sharpness of the detector can be assessed.

Posted in: Briefs, MDB, Briefs, Bio-Medical, Diagnostics, Medical, Calibration, Measurements, Imaging and visualization, Security systems, Medical equipment and supplies, Radiation

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Paracellular Drug Delivery Through Baker’s Yeast Microcapsules

The yeast has the ability to open up the junctions between cells to aid drug delivery. Oral mucosal drug delivery is an alternative method of systemic drug delivery that offers several advantages over both injectable and enteral methods. Since the oral mucosa is highly vascularised, drugs that are absorbed through the oral mucosa directly enter the systemic circulation, bypassing the gastrointestinal tract and first-pass metabolism in the liver. This avoids some of the problems typically experienced with traditional oral medication like analgesics that have to be absorbed by the lining of the stomach or the intestine, either of which they can irritate.

Posted in: Briefs, MDB, Briefs, Bio-Medical, Drug Delivery, Medical, Anatomy, Medical, health, and wellness, Pharmaceuticals

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Vibrating Quartz Sensor Characterizes Liquid Samples

This technology eliminates the need to run multiple tests to obtain a sample profile. A novel analytical technology characterizes liquids for healthcare applications. As a drop of liquid evaporates on a vibrating quartz sensor, it undergoes distinctive phase changes representing the unique chemical and physical characteristics of the sample. This unique “fingerprint” represents information that is not readily available from any combination of analytical methods currently in use.

Posted in: Briefs, MDB, Briefs, Bio-Medical, Medical, Patient Monitoring, Sensors, Sensors and actuators, Fluids and secretions, Vibration, Test equipment and instrumentation

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Reducing Field Distortion in Magnetic Resonance Imaging

An unconventional magnetic-field configuration would be used in SQUID MRI. A concept for a magnetic resonance imaging (MRI) system that would utilize a relatively weak magnetic field provides for several design features that differ significantly from the corresponding features of conventional MRI systems. Notable among these features are a magnetic- field configuration that reduces (relative to the conventional configuration) distortion and blurring of the image, the use of a superconducting quantum interference device (SQUID) magnetometer as the detector, and an imaging procedure suited for the unconventional field configuration and sensor.

Posted in: Briefs, MDB, TSP, Briefs, TSP, Bio-Medical, Diagnostics, Medical

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EPR Imaging at a Few Megahertz Using SQUID Detectors

This frequency range is better for imaging of humans and large animals.An apparatus being developed for electron paramagnetic resonance (EPR) imaging operates in the resonance- frequency range of about 1 to 2 MHz — well below the microwave frequencies used in conventional EPR. Until now, in order to obtain sufficient signal-to-noise radios (SNRs) in conventional EPR, it has been necessary to place both detectors and objects to be imaged inside resonant microwave cavities.

Posted in: Briefs, MDB, Briefs, Bio-Medical, Diagnostics, Medical

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A Constant-Force Resistive Exercise Unit

A constant-force resistive exercise unit (CFREU) has been invented for use in both normal gravitational and microgravitational environments. In comparison with a typical conventional exercise machine, this CFREU weighs less and is less bulky: Whereas weight plates and associated bulky supporting structures are used to generate resistive forces in typical conventional exercise machines, they are not used in this CFREU. Instead, resistive forces are generated in this CFREU by relatively compact, lightweight mechanisms based on constant-torque springs wound on drums. Each such mechanism is contained in a module, denoted a resistive pack, that includes a shaft for making a torque connection to a cable drum. During a stroke of resistive exercise, the cable is withdrawn from the cable drum against the torque exerted by the resistance pack.

Posted in: Briefs, MDB, Briefs, Bio-Medical, Medical, Rehabilitation & Physical Therapy

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Fluorogenic Cell-Based Biosensors for Monitoring Microbes

Fluorogenic cell-based sensor systems for detecting microbes (especially pathogenic ones) and some toxins and allergens are undergoing development. These systems harness the natural signaltransduction and amplification cascades that occur in mast cells upon activation with antigens. These systems include (1) fluidic biochips for automated containment of samples, reagents, and wastes and (2) sensitive, compact fluorometers for monitoring the fluorescent responses of mast cells engineered to contain fluorescent dyes. It should be possible to observe responses within minutes of adding immune complexes. The systems have been shown to work when utilizing either immunoglobulin E (IgE) antibodies or traditionally generated rat antibodies — a promising result in that it indicates that the systems could be developed to detect many target microbes. Chimeric IgE antibodies and rat immunoglobulin G (IgG) antibodies could be genetically engineered for recognizing biological and chemical warfare agents and airborne and food-borne allergens. Genetic engineering efforts thus far have yielded (1) CD14 chimeric antibodies that recognize both Gram-positive and Gram-negative bacteria and bind to the surfaces of mast cells, eliciting a degranulation response and (2) rat IgG2a antibodies that act similarly in response to low levels of canine parvovirus.

Posted in: Briefs, MDB, Briefs, Bio-Medical, Medical, Sensors

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