Patents


William Bennett, Peter Celliers, Luiz Da Silva, Michael Glinsky, Richard London, Duncan Maitland, Dennis Matthews, Peter Krulevich, and Abraham Lee
Opto-Acoustic Transducer for Medical Applications
U.S. Patent 5,944,687
August 31, 1999
An optically activated transducer for generating acoustic vibrations in a biological medium. The transducer is located at the end of an optical fiber, which may be located within a catheter. Energy for operating the transducer is provided optically by laser light transmitted through the optical fiber to the transducer. Pulsed laser light is absorbed in the working fluid of the transducer to generate a thermal pressure and consequent adiabatic expansion of the transducer head such that it does work against the ambient medium. The transducer returns to its original state by a process of thermal cooling. The motion of the transducer within the ambient medium couples acoustic energy into the medium. By pulsing the laser at a high repetition rate (continuous wave to 100 kilohertz), an ultrasonic radiation field can be established locally in the medium. This method of producing ultrasonic vibrations can be used in vivo for the treatment of stroke-related conditions in humans, particularly for dissolving thrombi. The catheter may also incorporate antithrombolytic drug treatments as an adjunct therapy, and it may be operated in conjunction with ultrasonic detection equipment for imaging and feedback control.

Frank J. Weber and Eberhard A. Spiller
Cleaning Process for EUV Optical Substrates
U.S. Patent 5,958,143
September 28, 1999
A cleaning process for surfaces with demanding cleanliness requirements, such as extreme ultraviolet (EUV) optical substrates. Proper cleaning of optical substrates prior to applying reflective coatings thereon is critical in the fabrication of the reflective optics used in EUV lithographic systems. The cleaning process involves ultrasonic cleaning in acetone, methanol, and a pH-neutral soap, such as FL-70, followed by rinsing in deionized water and drying with dry filtered nitrogen in conjunction with a spin rinse.


John W. Kury and Brian L. Anderson
Explosive Simulants for Testing Explosive Detection Systems
U.S. Patent 5,958,299
September 28, 1999
Explosives simulants that include nonexplosive components that facilitate testing of equipment designed to remotely detect explosives. The simulants are nonexplosive, nonhazardous materials that can be safely handled without any significant precautions. The simulants imitate real explosives in terms of mass density, effective atomic number, x-ray transmission properties, and physical form, including moldable plastics and emulsions/gels.


Paul R. Coronado
Method for Making Monolithic Metal Oxide Aerogels
U.S. Patent 5,958,363
September 28, 1999
A method for producing transparent, monolithic metal oxide aerogels of varying densities by preparing separately and then reacting a metal alkoxide solution with a catalyst solution. The resulting hydrolyzed-condensed colloidal solution is gelled, and the wet gel is contained within a sealed but gas-permeable containment vessel during supercritical extraction of the solvent. The containment vessel is enclosed within an aqueous atmosphere that is above the supercritical temperature and pressure of the solvent of the metal alkoxide solution.


Claude Montcalm, Daniel G. Stearns, and Stephen P. Vernon
Passivating Overcoat Bilayer for Multilayer Reflective Coatings for Extreme Ultraviolet Lithography
U.S. Patent 5,958,605
September 28, 1999
A passivating overcoat bilayer for multilayer reflective coatings for extreme ultraviolet (EUV) or soft x-ray applications to prevent oxidation and corrosion of the multilayer coating, thereby improving the EUV optical performance. The overcoat bilayer is composed of a layer of silicon or beryllium underneath at least one top layer of an elemental or a compound material that resists oxidation and corrosion. Materials for the top layer include carbon, palladium, carbides, borides, nitrides, and oxides. The thicknesses of the two layers that make up the overcoat bilayer are optimized to produce the highest reflectance at the wavelength range of operation. Protective overcoat systems composed of three or more layers are also possible.


Michael D. Perry, Paul S. Banks, Brent C. Stuart, and Scott N. Fochs
Aberration-Free, All-Reflective Laser Pulse Stretcher
U.S. Patent 5,906,016
September 28, 1999
An all-reflective pulse stretcher for laser systems employing chirped-pulse amplification enables on-axis use of the focusing mirror, thus allowing ease of use, significantly decreased sensitivity to alignment, and near aberration-free performance. By using a new type of diffraction grating that contains a mirror incorporated into the grating, the stretcher contains only three elements: (1) the grating, (2) a spherical and parabolic focusing mirror, and (3) a flat mirror. Addition of a fourth component, a retroreflector, enables multiple passes of the same stretcher, resulting in stretching ratios beyond the current state of the art in a simple compact design. The pulse stretcher has been used to stretch pulses from 20 femtoseconds to over 600 picoseconds (a stretching ratio in excess of 30,000).



Awards


A poster presentation created by a team of Livermore biomedical scientists recently garnered top honors at the California Breast Cancer Research Symposium in Los Angeles. The scientists are Kristen Kulp (lead author), Mark Knize, Mike Malfatti, Cyndy Salmon, and Jim Felton.
The poster, which focused on diet and how individuals differ in their susceptibility to breast cancer, won the Cornelius L. Hopper Scientific Achievement Award. Presented for the poster with the "Highest Impact on Breast Cancer," the Hopper award recognizes the University of California's recently retired Vice President for Health Affairs.
The Livermore scientists' poster analyzed the link between the presence of certain metabolites-the excretion products of carcinogens-and an individual's susceptibility to breast cancer. Specifically, the Livermore team examined whether the speed at which people excrete the metabolites and the relative amounts are related to the risk of developing breast cancer.
During their study, the Livermore researchers became the first scientists to develop a technique using mass spectrometry to detect phenylimidazo pyridine (PhIP) metabolites in human urine.

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