APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

18 Apr 2011

Volume 98, Issue 16, Articles (16xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 98, 163701 (2011); http://dx.doi.org/10.1063/1.3579156 (3 pages)

Thomas Jetzfellner, Amir Rosenthal, K.-H. Englmeier, Alexander Dima, Miguel Ángel Araque Caballero, Daniel Razansky, and Vasilis Ntziachristos
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Interpolated model-matrix optoacoustic tomography of the mouse brain

Thomas Jetzfellner, Amir Rosenthal, K.-H. Englmeier, Alexander Dima, Miguel Ángel Araque Caballero, Daniel Razansky, and Vasilis Ntziachristos

Appl. Phys. Lett. 98, 163701 (2011); http://dx.doi.org/10.1063/1.3579156 (3 pages) | Cited 2 times

Online Publication Date: 18 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Neuroscience investigations may significantly benefit from the availability of accurate imaging methods of brain parameters in small animals. In this letter, we investigate the imaging performance of the recently introduced interpolated model-matrix inversion (IMMI), in quantitative optoacoustic imaging of the mouse head. We compare the findings of the method against back-projection inversion methods that have more commonly been considered. We find that cross-sectional images of the mouse head accurately match anatomical structures seen on cryosliced head images serving as the gold standard. Moreover, superior imaging performance is found for IMMI compared to previously reported optoacoustic imaging of the mouse head.
Show PACS
87.63.L- Visual imaging
87.63.dh Ultrasonographic imaging
87.19.lh Optical imaging of neuronal activity
87.57.nf Reconstruction
02.60.Ed Interpolation; curve fitting

Label-free cell aggregate formation based on the magneto-Archimedes effect

Yoshitake Akiyama and Keisuke Morishima

Appl. Phys. Lett. 98, 163702 (2011); http://dx.doi.org/10.1063/1.3581883 (3 pages) | Cited 2 times

Online Publication Date: 19 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter demonstrates formation of cell aggregates by a label-free three-dimensional (3D) cell assembly method, which is based on the magneto-Archimedes effect. Gadolinium complex was added to the culturing medium to enhance the diamagnetic property of the cells, by which label-free magnetic manipulation became possible. Cytotoxicity of the gadolinium complex was confirmed to be sufficiently low for exposure less than one day. With this method, the cells aggregated into an egg-shape in about 20 min and became a spheroid in one day. These results suggest that this method is a promising approach to construct arbitrarily-shaped 3D tissues.
Show PACS
87.18.Ed Cell aggregation
87.85.Lf Tissue engineering
87.50.C- Static and low-frequency electric and magnetic fields effects
87.85.J- Biomaterials
Author Select

Microfluidic resonant waveguide grating biosensor system for whole cell sensing

Natalya Zaytseva, William Miller, Vasily Goral, Jerry Hepburn, and Ye Fang

Appl. Phys. Lett. 98, 163703 (2011); http://dx.doi.org/10.1063/1.3582611 (3 pages) | Cited 4 times

Online Publication Date: 19 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on a fluidic resonant waveguide grating (RWG) biosensor system that enables medium throughput measurements of cellular responses under microfluidics in a 32-well format. Dynamic mass redistribution assays under microfluidics differentiate the cross-desensitization process between the β2-adrenoceptor agonist epinephrine and the adenylate cyclase activator forskolin mediated signaling. This system opens new possibility to study cellular processes that are otherwise difficult to achieve using conventional RWG configurations.
Show PACS
87.80.Ek Mechanical and micromechanical techniques
87.17.-d Cell processes
87.14.ej Enzymes
Author Select

Feasibility of noninvasive cavitation-guided blood-brain barrier opening using focused ultrasound and microbubbles in nonhuman primates

Yao-Sheng Tung (童耀生), Fabrice Marquet, Tobias Teichert, Vincent Ferrera, and Elisa E. Konofagou

Appl. Phys. Lett. 98, 163704 (2011); http://dx.doi.org/10.1063/1.3580763 (3 pages) | Cited 2 times

Online Publication Date: 20 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In vivo transcranial and noninvasive cavitation detection with blood-brain barrier (BBB) opening in nonhuman primates is hereby reported. The BBB in monkeys was opened transcranically using focused ultrasound (FUS) in conjunction with microbubbles. A passive cavitation detector, confocal with the FUS transducer, was used to identify and monitor the bubble behavior. During sonication, the cavitation spectrum, which was found to be region-, pressure-, and bubble-dependent, provided real-time feedback regarding the opening occurrence and its properties. These findings demonstrate feasibility of transcranial, cavitation-guided BBB opening using FUS and microbubbles in noninvasive human applications.
Show PACS
87.63.D- Ultrasonography
87.19.um Blood-brain barrier
87.85.Ox Biomedical instrumentation and transducers, including micro-electro-mechanical systems (MEMS)

Optical trapping of synaptic vesicles in neurons

Chie Hosokawa, Suguru N. Kudoh, Ai Kiyohara, and Takahisa Taguchi

Appl. Phys. Lett. 98, 163705 (2011); http://dx.doi.org/10.1063/1.3579191 (3 pages) | Cited 2 times

Online Publication Date: 21 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate intracellular manipulation of synaptic vesicles in living neurons by optical trapping. When an infrared trapping laser is focused on synapses of a neuronal cell labeled with a fluorescent endocytic marker, fluorescence is observed at the focal spot. The fluorescence spectrum is attributed to fluorescent dye in the synaptic vesicles, indicating excitation by two-photon absorption of the trapping laser. The fluorescence intensity increases gradually within ∼ 100 s of laser irradiation, suggesting that trapping force causes vesicles assembly at the focus. Our method can be applied to manipulate synaptic transmission of a particular neuron in a neuronal network.
Show PACS
87.80.Cc Optical trapping
87.64.kv Fluorescence
87.19.lg Synapses: chemical and electrical (gap junctions)
87.17.-d Cell processes
42.62.Be Biological and medical applications
87.80.Dj Spectroscopies

Thermophotonic radar imaging: An emissivity-normalized modality with advantages over phase lock-in thermography

Nima Tabatabaei, Andreas Mandelis, and Bennett T. Amaechi

Appl. Phys. Lett. 98, 163706 (2011); http://dx.doi.org/10.1063/1.3582243 (3 pages) | Cited 3 times

Online Publication Date: 21 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
One major problem of frequency-domain photothermal radiometry, or alternatively in two-dimensional lock-in thermography, is the compromise one has to make between dynamic range (probing depth) and depth resolution. The thermal-wave radar incorporates chirped excitation through matched filtering to maintain good resolution and depth range inside a sample. This letter experimentally demonstrates the advantages of chirped modulation and introduces a thermophotonic modality of thermal-wave radar based on an emissivity-normalized, higher-dynamic-range contrast parameter known as cross-correlation phase. Finally, comparisons made on a biological (dental) sample show potential applications of the method.
Show PACS
84.40.Xb Telemetry: remote control, remote sensing; radar
84.40.Ua Telecommunications: signal transmission and processing; communication satellites

Longitudinal variations in the Poisson’s ratio of collagen fibrils

Marco P. E. Wenger and Patrick Mesquida

Appl. Phys. Lett. 98, 163707 (2011); http://dx.doi.org/10.1063/1.3567784 (3 pages) | Cited 1 time

Online Publication Date: 21 April 2011

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Atomic force microscopy imaging was used to determine the behavior of the D-banding geometry of collagen fibrils upon stretching in air under ambient conditions. The fibrils were strained by attaching them on a stretchable foil, the strain being monitored by the D-banding spacing and height. It was found that stretching fibrils increases the D-banding spacing and decreases the D-banding height. A simple, continuum mechanics model based on classical elasticity theory suggests that the gap has a smaller Poisson’s ratio than the overlap region.
Show PACS
87.19.rd Elastic properties
87.64.Dz Scanning tunneling and atomic force microscopy
02.40.-k Geometry, differential geometry, and topology
87.10.Pq Elasticity theory
87.14.em Fibrils (amyloids, collagen, etc.)
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close