eReport

April 2007

Probe to Detect Spread of Breast Cancer Co-Developed By UH Scientist

Physicist Audrius Brazdeikis, right, head of the Biomedical Imaging Group at the Texas Center for Superconductivity at the University of Houston, confers with London surgeon Dr. Michael Douek about a unique procedure for staging and treating breast cancer. UH and University College of London teams developed a probe to enable surgeons to better detect the spread of breast cancer, and Douek is conducting a clinical trial of the device in England.

Device to Locate Magnetic Nanoparticles in Lymph Nodes

High-temperature superconductors hold the key to a handheld tool for surgeons that promises to be more accurate, cost-effective and safer than existing methods for staging and treating various cancers, including breast cancer.

Audrius Brazdeikis, research assistant professor of physics in the College of Natural Sciences and Mathematics at the University of Houston and Quentin Pankhurst, a professor of physics from the University College of London (UCL), have developed a novel detection procedure combining nanotechnology and advanced magnetic sensing based on high-temperature superconductors. Their innovation will enable surgeons to more effectively locate the sentinel lymph node – the first lymph node to which a tumor’s metastasizing cancer cells will drain.

The researchers produced an ultrasensitive magnetic probe to detect minuscule magnetic fields in the body. The probe is a supersensitive magnetometer, an instrument used to track the presence of clinically introduced magnetic nanoparticles. During breast cancer surgery, a surgeon will inject a magnetic nanoparticle dye, already approved as an imaging contrast agent by the Food and Drug Administration, into the tumor or into tissues surrounding the tumor.

Receiving a $250,000 grant to be used from 2004 to 2006 from the United Kingdom Department of Trade and Industry under the UK-Texas Bioscience Collaboration Initiative, Brazdeikis and Pankhurst were required to show “proof of concept” by building a device and showing it worked. An ethics committee in the UK since has approved the detection procedure for a clinical trial of women undergoing breast cancer surgery at University College Hospital, London.

Dr. Michael Douek, a London surgeon who specializes in breast surgery and is a senior lecturer at UCL, is overseeing the trial and used the probe for the first time in surgery in December. Douek, who visited Houston recently in preparation for the testing, said that the ethics committee gave the hospital permission to use the probe in 10 surgeries and that after a review of those procedures, the number could increase to 100.

“We expect to start new clinical trials in Japan and Europe before the end of 2007,” said Brazdeikis. “Our technology will be extensively validated by different surgeons in various countries.”

Brazdeikis, who heads the Biomedical Imaging Group at the Texas Center for Superconductivity at UH (TcSUH), said a goal of the grant was to commercialize biomedical technology developed at universities through collaborative research. He and Pankhurst, deputy director of the London Centre for Nanotechnology, have formed a medical devices company, Endomagnetics, Inc, to bring their technology to the marketplace and patented the probe.

“The company plans to roll out the production of the technology in 2008,” said Brazdeikis. “We hope that in the next two to three years practice assisted with our new probe will become more widely adopted by surgeons.”

Endomagnetics also already has garnered recognition from such key world figures as England’s Prince Andrew, his country’s special representative for international trade and investment, who highlighted new technology developed by the nanotechnology industry at the Nano-TX ’06 conference in Dallas. He cited the UH-UCL collaboration and Endomagnetics’ as an “exciting example of the early stages of this kind of progress.”

“The partnership has resulted in a technology used to locate lymph nodes for the staging and treatment of various forms of cancer, including breast cancers and melanomas, and some of the more disfiguring and demoralizing forms of cancer,” he said, according to a transcript of his remarks.

“Although the technology has potential for use in the staging and treatment of other cancers, including lung and prostate cancer, the instrument needs to be customized for the type of surgery,” said Douek, who has advised the researchers from the beginning of the probe’s development. “We went through a whole series of different probes during the course of a year. I was interested in being part of the project because of my interest in magnetic resonance imaging. This is an extension of that technology.”

A surgeon holds the probe, which incorporates two sets of coils connected to a sensor. One set of coils magnetizes the magnetic particles and the second detects the magnetic response from those particles. The sensor, known as an HTS SQUID (or high-temperature superconducting quantum interference device) is located in a cryogenic vessel on a cart and is submerged in liquid nitrogen that cools the sensor to 77 K, equivalent to -320.5°F. The system uses custom-built electronics and software on a laptop computer to give the surgeon visual and audio feedback while tracking the magnetic nanoparticles in the body.

“When breast cancer is diagnosed, and a tumor has been located, a critically important issue is whether the cancer has spread to other parts of the body – a process that occurs via the transport of metastatic cancer cells through the lymphatic system,” said Brazdeikis. “The surgeon looks for lymph nodes close to the cancer. They are not easy to find. The probe is a tool for the surgeon to use during the surgery to locate the sentinel lymph node.”

Existing practice calls for a breast cancer patient to receive two preoperative injections – a radioactive isotope and a blue dye, eight to 12 hours before surgery, frequently requiring hospitalization the night before the operation. Later, in the operating room, the surgeon uses a handheld gamma probe, aided by the visual observation of the dye, to locate the lymph node with the highest radioactivity.

“Surgeons have a very small window of opportunity to locate the lymphatic nodes that the cancer drains into,” Brazdeikis said. “Our technology offers unprecedented quality and value of care benefits to patients, doctors and hospital administrators over existing procedures.”

The UH-UCL technology allows a surgeon to administer one injection, the magnetic dye that takes only 10 to 15 minutes to work and eliminates the need for a nuclear medicine practitioner to inject the radioactive material. A patient thus may not have to be hospitalized while waiting, and the technology eliminates unnecessary patient and surgeon exposure to radioactivity.

“We introduce a paradigm-shifting new technology for the staging and treatment of breast and other forms of cancer,” Brazdeikis said. “It will be very appealing for surgeons to take this technology into their practice.”

Vacuumschmelze Presents A New Range Of Shielded Current Transformers

Hanau-based Vacuumschmelze GmbH & Co. KG presents a new family of current transformers designed specifically for use in IEC-standard electronic electricity meters. The new transformers also comply with an array of national standards for meters that are tamper-proof against manipulation attempts using external magnetic fields.

Electronic electricity meters are increasing in popularity all over the world. Free from mechanical wear and tear, they permit remote reading, are network-enabled and support multiple tariffs. However, rising energy costs are accompanied by an increase in the number of cases where meters of this type are subjected to manipulation. External magnetic fields can be used to influence the measuring circuit and reduce the power consumption registered. Although obtaining large permanent magnets with high magnetic induction was extremely difficult in the past, today such magnets are relatively widespread and easy to find via the Internet and other sources.

The current transformers in the new X151 range, which also features integrated shielding, are meters that are largely proof against manipulation attempts using DC magnetic fields of permanent magnets, which can generate air induction levels exceeding 300 mT. Integrated shielding has the benefit that shielding of the entire meter - a complex procedure involving high space requirements – is unnecessary, thus enabling compact meters to be designed that feature high immunity against external magnetic fields.

The basic design principle used in Vacuumshmelze current transformers itself offers the benefit of ultra-low sensitivity to magnetic alternating current fields, owing to their annular symmetry. The IEC Standard 62053-21 specifies the maximum permissible additional error for an electronic Class 1 meter as 2 percent at a test field strength of 0.5 mT in ambient air at normal operating frequency.

MMG Offers High Stability, Low-Loss Manganese-Zinc Ferrite Core Materials

P roviding power component manufacturers with a reliable source of magnetic materials, TT electronics MMG continues to offer high stability manganese-zinc ferrite core materials. Designated the F58 and P11 materials, they cover a frequency range from 10 kHz to 1 MHz.

“Even as other magnetics suppliers are discontinuing production of their less popular grades, including F58 and P11 equivalent materials, MMG continues to offer them,” said Brian Wiese, director of sales and marketing for MMG. “With our ongoing production, we are able to assure a stable source of supply to customers so they do not have to worry about availability in meeting their requirements. They can have the materials in four to six weeks.”

Both the F58 and P11 ferrites feature high stability, low TCRs and low loss factor, making them well suited for applications involving filter networks, proximity switches and gate drive transformers for switch mode power supplies.

The F58 material features a frequency range of 200 kHz to 1 MHz and an initial permeability of 750 when measured at 10 kHz and 0.1 mT (25ºC). With a frequency range from 10 kHz to 500 kHz, the P11 material features an initial permeability of 2,250 when measured at 10 kHz and 0.1 mT (25ºC).

The F58 and P11 ferrite materials are available in standard RM and pot core geometries, while the F58 material is also available in toroidal core configuration. Additional shapes are available upon request.

Lead time for the custom ferrite materials ranges from stock to 4 to 6 weeks.

Magnesy Baildon Ltd is a Polish company with over 55 years of experience of Alnico magnets production. In the last two years the company invested in technology, that was invented by its high qualified engineers. This innovative technology allows to product Alnico rods up to 300 mm long without shrinkage cavity. The dimensions of rods that can be manufactured using this new method are: ø3, ø4, ø5, ø6, ø7 mm.

The company looks for business partners from all over the world to establish stable cooperation on the field of delivering the longest Alnico rods. We invite you to visit the company website: http://www.magnesy.com.pl

Demagnetization Simulator Provides Design Optimization Tool for Permanent Magnet

Vector Fields' DEMAG electromagnetic modeling software provides a powerful tool for simulating permanent magnet characteristics.

Components and Equipment

Vector Fields has released a 3-D version of its electromagnetic modeling software for simulating permanent magnet characteristics. Believed to be unique, the package offers a powerful dedicated tool for developers of magnetic components and a very broad range of electrical and other equipment.

Called DEMAG, the solver allows designers to optimize equipment designs by accurately simulating both the magnetization process and the subsequent demagnetization effects that might be encountered.

Permanent magnets are usually magnetized in a fixture comprising an electromagnet driven by a capacitor discharge circuit, iron former and the un-magnetized material. DEMAG can be used to model complete processes like this, including the capacitor discharging into the electromagnet, eddy currents induced in the formers and magnets and non-linear saturation of the materials.

Cut-away view of a magnetizing fixture designed to produce a 6-pole permanent magnet, with skewed magnetization to reduce cogging torque, produced using Vector Fields' DEMAG software.

This is critical as many large scale users, particularly of ferrites, create the finished magnets during equipment production, often after they are assembled into the final product. By being able to accurately simulate the real-world characteristics created by such processes, including the effects of eddy currents on magnetic distribution in the component for example, users have a powerful design optimization tool.

The solver includes the ability to model the recoil behavior of magnets, and further demagnetization as a function of field and temperature history, factors that can have a significant impact on the service performance of devices.

DEMAG represents permanent magnet materials by interpolation from actual measured BH (magnetic induction, and applied field) characteristics, and can be configured to simulate any magnetic material. Rather than using a theoretical magnetization distribution, the true distribution is calculated from the properties of the magnetizing fixture. The performance of permanent magnets is therefore predicted with great accuracy.

DEMAG runs as a module within Vector Fields’ Opera computer aided engineering (CAE) package. The CAE software provides a complete 3-D design-model-optimize toolchain to speed the design of components and systems incorporating electromagnetic materials.

Simulation showing the magnitude of the radial component of magnetization on a 6-pole permanent magnet, produced using Vector Fields' DEMAG software.

Once the calculated magnetization of the model is available, it can then be used in all other Opera modules - such as solvers for the design of rotating machines or linear actuators - to study and optimize the performance of the overall equipment itself.

This allows designers to simulate and study the effects of service factors such as fault currents and high operating temperatures, for example. Elevated temperatures in particular can be a particular problem when trying to employ advanced magnetic materials such as neodymium iron boron.

austriamicrosystems Launches the AS5140H – the First Qualified 10-bit Magnetic Rotary Encoder with Ambient Temperature up to

austriamicrosystems has expanded its magnetic rotary encoder family with the AS5140H 10-bit encoder. The innovative rotary encoder IC is fully qualified to AEC-Q100 and designed for applications in an ambient temperature range up to 150°C.

With a resolution of 0.35°, the AS5140H can recognize 1,024 positions within one 360° turn, accessible with either a serial or a PWM (Pulse-Width Modulation) interface. In addition, there are three differently programmable incremental outputs available to the user; one of these delivers a three-phase commutation signal for brushless DC motors.

Several features of the AS5140H, including user-specific zero programming, a diagnostic function for correct positioning of the magnet, or the ability to recognize interruptions to the power supply, are already standard in austriamicrosystems’ encoder product family. In addition, a "daisy chain" mode has been added in the AS5140H, so that position data can be read serially over a two-wire bus.

“With the first high temperature-qualified high accuracy magnetic rotary encoder, we present another significant innovation to the market. Qualified to function in an ambient temperature of up to 150 °C , the AS5140H is ideally suitable for the harsh conditions in automotive applications“, said Bernhard Czar, Automotive Marketing Director at austriamicrosystems. “The AS5140H is a premium device within austriamicrosystems’ industry-leading rotary encoder family which we will continue to expand with additional products for difficult and rugged environments .”

Due to an integrated voltage regulator the AS5140H operates at either 3.3 V or 5 V. Despite the wide ambient temperature range, no additional temperature compensation and calibration of the device is required. The AS5140H is available in a lead-free SSOP-16 package. Samples are available immediately.

Advanced Magnetics Announces Settlement of Lawsuit with Cytogen Corporation
Advanced Magnetics, Inc. has settled its lawsuit with Cytogen Corp. Both parties have agreed to dismiss the lawsuit and drop all claims against each other. Under the terms of the settlement agreement, Advanced Magnetics and Cytogen agreed to terminate both the license and marketing agreement and the supply agreement between the parties, effective immediately.

With the termination of its agreements with Cytogen, Advanced Magnetics has re-acquired US marketing rights to Combidex, Advanced Magnetics' investigational functional molecular imaging agent for use in conjunction with magnetic resonance imaging to aid in the differentiation of cancerous from normal lymph nodes, as well as the US marketing rights to ferumoxytol for oncology imaging applications. Under the terms of the settlement agreement, Advanced Magnetics will pay Cytogen a lump sum payment of $4 million in cash and release to Cytogen the 50,000 shares of Cytogen common stock currently being held in escrow under the terms of the original license and marketing agreement.

“We are very pleased to have reached an amicable settlement with Cytogen and to have re-acquired the US marketing rights to Combidex,” said Brian J.G. Pereira, chief executive officer and president of Advanced Magnetics. “We look forward to advancing our development programs for both ferumoxytol as an intravenous iron replacement therapeutic and Combidex as an imaging agent in the months ahead.”

Ferumoxytol, the company's key product candidate, is in Phase III multi- center clinical trials for use as an iron replacement therapeutic in chronic kidney disease patients, whether or not on dialysis.

Combidex, the company's other product under development, is an investigational functional molecular imaging agent consisting of iron oxide nanoparticles for use in conjunction with magnetic resonance imaging to aid in the differentiation of cancerous from normal lymph nodes.

MTS Systems Corp., Sensors Division has unveiled the first phase of its world-wide website redesign, which features a common layout and functionality across all regional Sensors Division websites. The site adds secure value-added information access for customers, including a product generator.

MTS Sensors Division’s new website design creates a global look and feel with the use of top and left-hand navigation menus, which make the site easy to use while retaining quick access to information and downloads. Content is customized for each region, maintaining the local business culture of each major geographical region.

The new MTS Sensors website also provides customers with value-added information access through a secure site that features a new online product generator. The new tool is powered by 3D PartStream.NET from SolidWorks Corp. and enables customers to access an interactive online 3D part catalog. With the product generator, customers can build a product, view it, then download 2D or 3D computer-aided design (CAD) drawings of the product in virtually any format currently used by CAD systems worldwide. The product generator also provides a part number and allows the customer to directly request a quote with the click of a button. The first products available for the generator are the Temposonics Model R-Series linear-position sensors; remaining product lines will be added throughout the next few months.

“The new website design reinforces our worldwide capabilities for product design and development, sales and technical support, and manufacturing, helping us build and solidify the MTS brand globally,” said Drew Smedley, director of Global Marketing for MTS Sensors. “Creating the secure portion of the website helps us deliver new value-added services for our customers and provide them access to a greater range of support material.”

The first phase of the launch includes the Americas, Europe (available in German and English), and Asia (Japanese) regional sites. Italian, Spanish and Chinese language translations will follow in the coming months.

The 2007 Magnetics Conference took place April 4-5 in Chicago, Ill. and featured more than 30 technical presentations from today's foremost leaders in magnetic applications, materials and technology.

For those of you who were unable to attend but wish to stay up-to-date on the most recent industry advancements, the conference proceedings, attendee list and exhibitor information is all available on CD-ROM.

For more information about ordering the Conference CD, contact Heather Krier at heatherk@infowebcom.com.

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