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This page shows you the 20 most read items in the past 30 days within this specialty in the MedWorm directory.

Analysis of couch position tolerance limits to detect mistakes in patient setup.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This work investigates the use of the tolerance limits on the treatment couch position to detect mistakes in patient positioning and warn users of possible treatment errors. Computer controlled radiotherapy systems use the position of the treatment couch as a surrogate for patient position and a tolerance limit is applied against a planned position. When the couch is out of tolerance a warning is sent to a user to indicate a possible mistake in setup. A tight tolerance may catch all positioning mistakes while as the same time sending too many warnings; while a loose tolerance will not catch all mistakes. We develop a s...
Source: Journal of Applied Clinical Medical Physics - November 20, 2009 Category: Physics Authors: Hadley SW, Lam KL, Balter JM Tags: J Appl Clin Med Phys Source Type: journals

Microscopic origin of bipolar resistive switching of nanoscale titanium oxide thin filmsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We report a direct observation of the microscopic origin of the bipolar resistive switching behavior in nanoscale titanium oxide films. Through a high-resolution transmission electron microscopy, an analytical transmission electron microscopy technique using energy-filtering transmission electron mi ... [Appl. Phys. Lett. 95, 162108 (2009)] published Wed Oct 21, 2009. (Source: Applied Physics Letters)
Source: Applied Physics Letters - October 22, 2009 Category: Physics Source Type: journals

Anthrax investigation still yielding surprising findingsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
NatureNews: The deadly bacterial spores mailed to victims in the US anthrax attacks, scientists say, share a chemical 'fingerprint' that is not found in bacteria from the flask linked to Bruce Ivins, the biodefence researcher implicated in the crime. At a biodefence meeting on 24 February in Baltimore, Maryland, Joseph Michael, a materials scientist at Sandia National Laboratories in Albuquerque, New Mexico, presented analyses of three letters sent to the New York Post and to the offices of Senators Tom Daschle and Patrick Leahy. Spores from two of those show a distinct chemical signature that includes silicon, oxygen, ir...
Source: Physics Today News Picks - February 26, 2009 Category: Physics Authors: Physics Today Source Type: news

Bipolar resistive switching in individual AuNiOAu segmented nanowiresEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Edward D. Herderick, Kongara M. Reddy, Rachel N. Sample, Thomas I. Draskovic, and Nitin P. Padture Evidence for bipolar resistive switching is reported in individual metal-oxide-metal (MOM) nanowires in the system AuNiOAu, and a plausible mechanism for the same is presented. The MOM nanowire architecture may be well suited for much needed fundamental studies of resistive switching because it prov ... [Appl. Phys. Lett. 95, 203505 (2009)] published Tue Nov 17, 2009. (Source: Applied Physics Letters)
Source: Applied Physics Letters - November 19, 2009 Category: Physics Source Type: journals

Solar decathlon competition comes to WashingtonEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Physics Today: The next generation of energy efficient houses appeared in Washington this week as part of the Department of Energy's 2009 solar decathlon competition (pdf). The competition, held on the Washington Mall, judged 20 homes based on aesthetics, functionality and energy measurements. The University of Minnesota's 565 sq. ft solar home called ICON cost half a million dollars to build and came 5th in the competition. Student's have to design in factors such as is there enough solar thermal hot water for the big and small dishwashers in the kitchen and the clothes washer in a cabinet next to the small bathroom?...
Source: Physics Today News Picks - October 14, 2009 Category: Physics Authors: Physics Today Source Type: news

Influence of nanocrystal size on dielectric functions of Si nanocrystals embedded in SiO matrixEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Rong-Jun Zhang, Yi-Ming Chen, Wei-Jie Lu, Qing-Yuan Cai, Yu-Xiang Zheng et al. The complex dielectric functions of Si-nanocrystals (nc-Si) with different sizes embedded in SiO matrix synthesized by SiO/SiO superlattice approach is obtained by spectroscopic ellipsometry. The MaxwellGarnett effective medium approximation and the Lorentz oscillator model are employed in the spect ... [Appl. Phys. Lett. 95, 161109 (2009)] published Fri Oct 23, 2009. (Source: Applied Physics Letters)
Source: Applied Physics Letters - October 24, 2009 Category: Physics Source Type: journals

Turning a cellphone into a microscopeEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
NYTimes.com: Microscopes are invaluable tools to identify blood and other cells when screening for diseases like anemia, tuberculosis, and malaria. But they are also bulky and expensive. Now an engineer, using software that he developed and about $10 worth of off-the-shelf hardware, has adapted cellphones to substitute for microscopes. (Source: Physics Today News Picks)
Source: Physics Today News Picks - November 9, 2009 Category: Physics Authors: Physics Today Source Type: news

Why so few East German Max Planck directors?Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Science: When the Max Planck Society planted institutes across the former East Germany, it recruited scientists from around the world for its ambitious project. But only two out of more than 60 directors in the newly founded institutes were recruited from the East itself. Today, the society has 267 active directors; only five grew up on the eastern side of the divided Germany. And only one started a career before 1989. Those statistics are a sign of the mixed blessings that reunification brought for East German scientists. For many, especially the younger ones, it was a great opportunity. But others were set adrift wh...
Source: Physics Today News Picks - November 6, 2009 Category: Physics Authors: Physics Today Source Type: news

Turning a cell phone into a microscopeEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
NYTimes.com: Microscopes are invaluable tools to identify blood and other cells when screening for diseases like anemia, tuberculosis, and malaria. But they are also bulky and expensive. Now an engineer, using software that he developed and about $10 worth of off-the-shelf hardware, has adapted cell phones to substitute for microscopes. (Source: Physics Today News Picks)
Source: Physics Today News Picks - November 9, 2009 Category: Physics Authors: Physics Today Source Type: news

The Stasi spies in scienceEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Nature: In 1992, three years after the fall of the Berlin Wall, a spy walked into the US embassy in Warsaw and offered to sell the CIA the real and code names of all intelligence agents from the HVA (Hauptverwaltung Aufklärung)—the foreign department of the Stasi, the East German Ministry for State Security. The CIA bought the highly sensitive information for a mere US$75,000. The spoils—released to the Berlin Stasi archive and made available to history professor Kristie Macrakis at the Georgia Institute of Technology in Atlanta in 2005—have the potential to alter popular perceptions of the activities o...
Source: Physics Today News Picks - September 30, 2009 Category: Physics Authors: Physics Today Source Type: news

Laser creates record-breaking protonsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
High-energy protons could yield compact source for cancer therapy (Source: PhysicsWeb News)
Source: PhysicsWeb News - November 9, 2009 Category: Physics Source Type: news

Cancer mortality among German aircrew: second follow-up.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Aircrew members are exposed to cosmic radiation and other specific occupational factors. In a previous analysis of a large cohort of German aircrew, no increase in cancer mortality or dose-related effects was observed. In the present study, the follow-up of this cohort of 6,017 cockpit and 20,757 cabin crew members was extended by 6 years to 2003. Among male cockpit crew, the resulting all-cancer standardized mortality ratio (SMR) (n = 127) is 0.6 (95% CI 0.5-0.8), while for brain tumors it is 2.1 (95% CI 1.0-3.9). The cancer risk is significantly raised (RR = 2.2, 95% CI 1.2-4.1) among cockpit crew members employed 30...
Source: Radiation and Environmental Biophysics - October 15, 2009 Category: Physics Authors: Zeeb H, Hammer GP, Langner I, Schafft T, Bennack S, Blettner M Tags: Radiat Environ Biophys Source Type: journals

Dust charging effects on test charge potential in a multi-ion dusty plasmaEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
S. Ali The DebyeHuckel and oscillatory wake potentials caused by a test charge are studied in a multi-ion dusty plasma, whose constituents are the Boltzmann distributed electrons and light positive ions, the heavy mobile negative ions, and static but charge fluctuating dust particles. For this purpose, flu ... [Phys. Plasmas 16, 113706 (2009)] published Wed Nov 18, 2009. (Source: Physics of Plasmas)
Source: Physics of Plasmas - November 19, 2009 Category: Physics Source Type: journals

Quantitative characterization of turbid media using pressure contrast acousto-optic imagingEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
An acousto-optic imaging technique suitable for the local and quantitative determination of subsurface optical properties in turbid media is presented. Acousto-optic signals elicited by ultrasound pulses at two different peak pressures in turbid media are detected by using ... (Source: Optics Letters)
Source: Optics Letters - September 14, 2009 Category: Physics Authors: Puxiang LaiRonald A. RoyTodd W. Murray Source Type: journals

The dynamics of a non-equilibrium bubble near bio-materials.Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In many medical treatments oscillating (non-equilibrium) bubbles appear. They can be the result of high-intensity-focused ultrasound, laser treatments or shock wave lithotripsy for example. The physics of such oscillating bubbles is often not very well understood. This is especially so if the bubbles are oscillating near (soft) bio-materials. It is well known that bubbles oscillating near (hard) materials have a tendency to form a high speed jet directed towards the material during the collapse phase of the bubble. It is equally well studied that bubbles near a free interface (air) tend to collapse with a jet directed ...
Source: Physics in Medicine and Biology - October 8, 2009 Category: Physics Authors: Ohl SW, Klaseboer E, Khoo BC Tags: Phys Med Biol Source Type: journals

Photoacoustic guidance of high intensity focused ultrasound with selective optical contrasts and time-reversalEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Arik R. Funke, Jean-Francois Aubry, Mathias Fink, Albert-Claude Boccara, and Emmanuel Bossy The authors present a method of focusing high intensity ultrasound by time-reversing the photoacoustic response of an optically selective target in a nonselective background. The target's photoacoustic response was isolated from the background by subtracting the photoacoustic waveforms obtained at d ... [Appl. Phys. Lett. 94, 054102 (2009)] published Tue Feb 3, 2009. (Source: Applied Physics Letters)
Source: Applied Physics Letters - February 4, 2009 Category: Physics Source Type: journals

Dynamics of microbubble generation and trapping by self-focused femtosecond laser pulsesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Kun Yang, Yun Zhou, Qiushi Ren, Jing Yong Ye, and Cheri X. Deng Different from conventional optical tweezers used for trapping high refractive index micron-sized particles, bubble generation and trapping by femtosecond laser offer a unique strategy to manipulate microbubbles. Using high frequency ultrasound imaging and fast-frame optical video microscopy, we obt ... [Appl. Phys. Lett. 95, 051107 (2009)] published Thu Aug 6, 2009. (Source: Applied Physics Letters)
Source: Applied Physics Letters - August 7, 2009 Category: Physics Source Type: journals

Ultrasound-modulated optical imaging using a high-power pulsed laser and a double-pass confocal Fabry-Perot interferometerEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We report the use of short ultrasonic bursts and high-peak-power laser pulses to detect absorbing objects in thick scattering media (SMs). The detection of ultrasound-tagged photons is performed with a double-pass confocal Fabry-Perot interferometer. Photons shifted by the fundamental and harmonic ... (Source: Optics Letters)
Source: Optics Letters - October 30, 2009 Category: Physics Authors: Guy RousseauAlain BlouinJean-Pierre Monchalin Source Type: journals

IV Euro-Asian Symposium “Trends in MAGnetism”: Nanospintronics. EASTMAG-2010Email this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Conference: 28 Jun 2010 - 2 Jul 2010, Ekaterinburg, Russian Federation. Organized by Institute of Metal Physics, Ural Branch of the Russian Academy of Sciences . (Source: PhysicsWeb Events)
Source: PhysicsWeb Events - November 9, 2009 Category: Physics Source Type: events

Two-dimensional nanosecond electric field mapping based on cell electropermeabilizationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Nanosecond, megavolt-per-meter electric pulses cause permeabilization of cells to small molecules, programmed cell death (apoptosis) in tumor cells, and are under evaluation as a treatment for skin cancer. We use nanoelectroporation and fluorescence imaging to construct two-dimensional maps of the electric field associated with delivery of 15 ns, 10 kV pulses to monolayers of the human prostate cancer cell line PC3 from three different electrode configurations: single-needle, five-needle, and flat-cut coaxial cable. Influx of the normally impermeant fluorescent dye YO-PRO-1 serves as a sensitive indicator of membrane perme...
Source: PMC Biophysics - November 11, 2009 Category: Physics Authors: Meng-Tse ChenChunqi JiangP. Thomas VernierYu-Hsuan WuMartin Gundersen Source Type: journals