Bioimaging Rocks

Nanoscopy at 40 nm resolution!

2008-06-03T13:10:00.002+08:00

Dear All

I will discuss a recent paper by Stefan Hell's group claiming a PSF fluorescence spot of 40 nm. Now they have started calling it "nanoscopy" instead of "microscopy" that I think is right terminology for the 21st century optical ~~micro~~nanoscopy.

Cheers

Shakil

Nature Methods - 5, 539 - 544 (2008)
Published online: 18 May 2008; | doi:10.1038/nmeth.1214

Spherical nanosized focal spot unravels the interior of cells

Roman Schmidt¹, Christian A Wurm¹, Stefan Jakobs¹, Johann Engelhardt², Alexander Egner¹ & Stefan W Hell^1,²

Journal Club, 5th March 2008

2008-03-04T12:20:00.002+08:00

It's journal club, again. I'll be discussing a paper previously sent to all of you yesterday. Enjoy what you can of it.

Journal Club on 27th Feb

2008-02-24T20:20:00.006+08:00

HILO Microscopy
Dear all,

I will be discussing about HILO microscopy which claims better resolution than fluorescence microscopy. It is based on a special illumination technique.

Date : 27th Feb
Time : 3pm onwards
Abstract : http://www.nature.com/nmeth/journal/v5/n2/abs/nmeth1171.html

Regards,
Naveen

Journal Club Roster

2008-02-21T14:23:00.002+08:00

Hi all,

The following is the final roster for this semester:

Jan 30 Wai Teng
Feb 13 Si Ke
Feb 20 Dr. Shakil
Feb 27 Naveen
Mar 5 Elijah
Mar 12 Shalin
Mar 19 Gong Wei
Mar 26 Shan Shan
Apr 2 Dr. Zheng

Please let me know one week in advance if you want to shift to another slot.

Best,
shan

Next Journal Club Meeting

2008-02-19T11:51:00.003+08:00

Dear Colleagues
I will discuss about Digital Holography and Scanning Optical Holography in our next Journal Club meeting.
Shakil

Nature Photonics Highlights

2008-01-21T11:09:00.000+08:00

Dear all,

Nature Photonics Magazine is opening up highlights articles from year 2007.

http://www.nature.com/nphoton/focus/1st_anniversary/index.html

Cheers,
shan

Regarding journal club schedule for new semester

2008-01-17T15:51:00.000+08:00

Dear all,

It seems that people are having some seminar or conference throughout next week - so we will cancel JC for next week and resume on 29th Jan (tue) 3pm at pantry area. Our schedule for journal clubs in this new sem will be temporarily on Tues afternoons unless there is further change.

The person leading next discussion will be Wai Teng.

Best regards,
SS

28/1/08 It seems that Wednesday is a better date.

5th International Symposium on Nanomanufacturing

2008-01-17T12:42:00.000+08:00

Dear all,

There is a conference on nanomanufacturing next week, and there are some interesting talks.
Here is the link:
http://isnm2008.org/

Best,
WT

Journal club 17, Jan, 2008

2008-01-15T16:03:00.000+08:00

Hi all,

Now it is a new semester and our Journal club begins again.
This week I will be presenting a paper on inverse problem and high resolution OCT.
The title of the paper is:

"Nonparaxial vector-field modeling of optical coherence tomography and interferometric synthetic aperture microscopy"

Date: 17, Jan
Time: 10.30am
Venue: pantry area

Best Wishes,
Gong Wei

8th European Light Microscopy Initiative Conference

2008-01-13T11:37:00.000+08:00

Dear Friends,
This conference seems to focus mainly on practical aspects and involves many workshops.
The conference is in May and the submissions are in January end. The website is: http://www.elmi08.unibas.ch/index.html. To get flavor of topics of interest look at last year's programme: http://www.york.ac.uk/depts/biol/tf/ELMI/programme.htm.

Cheers,
Shalin

CFP: Focus on Microscopy 2008

2008-01-13T10:45:00.001+08:00

Sorry Folks,
I didn't post this in time. The deadline is January 15 (This Tuesday). Following announcement came from confocal list.

---------------------------------------------------------------------------------
FOCUS ON MICROSCOPY 2008 - Osaka, Awaji Island, Japan - April 13-16, 2008
----------------------------------------------------------------------------------

21th International Conference on 3D Image Processing in Microscopy
20th International Conference on Confocal Microscopy

Dear Colleagues,

January 15, 2008, the deadline for abstract submission for the Osaka, Awaji Island FOM2008 conference, is nearing. Please submit your abstract by that date.

Abstracts for oral and poster presentations can now be submitted preferably through the conference website: http://www.FocusOnMicroscopy.org where also the conference registration has opened and hotel booking information is available.

The program for the conference will be finalized and available on our website on Feb. 6, 2008. Authors will be informed individually by E-mail on the placement of their contribution in the program.

After the successful FOM2007 conference held in Valencia in April last year, the next conference: Focus on Microscopy 2008 will take place in Osaka, Awaji Island, Japan from Sunday, April 13 to Wednesday, April 16, 2008. As the next in a series of unique interdisciplinary meetings on advanced multidimensional light microscopy and image processing, the conference will be hosted by the University of Osaka.

Focus on Microscopy 2008 is the continuation of a yearly, well attended conference series presenting the latest innovations in optical microscopy and their application in biology, medicine and the material sciences. Key subjects for the conference are the theory and practice of 3D optical imaging, related 3D image processing, together with reporting on the ever increasing spatial resolutions and sophisticated imaging modes coming available in sectioning microscopy.

The conference series is in addition known for covering the rapid development of advanced fluorescence labeling techniques for the confocal and multi-photon 3D imaging of -live- biological specimens. Laser light in combination with 3D microscopy is starting to play an increasingly important role as a tool at sub-micrometer scales in cell biology for dissection and isolation of structures of interest for subsequent analysis.

Important dates:
Deadline for the submission of abstracts: January 15, 2008
Acceptance of contributions, draft program: February 6, 2008
Deadline for early registration: February 26, 2008

We would like to welcome you to Osaka, Awaji Island for the FOM2008
conference and exhibition. To stay informed about the conference please
leave your name and email at: http://www.FocusOnMicroscopy.org/stayinformed

On behalf of the organising committee,

- Satoshi Kawata and Katsumasa Fujita, Department of Applied Physics, Osaka University, RIKEN, Wako City, Japan
E-mail: fom2008@ap.eng.osaka-u.ac.jp
- Fred Brakenhoff, Swammerdam Institute for Life Sciences, University of Amsterdam, The Netherlands
--
E-mail: info2008@FocusOnMicroscopy.org
Web: www.FocusOnMicroscopy.org

Break of JC for Dec holidays

2007-12-12T15:37:00.000+08:00

Dear all,

It is almost the end of the year and thanks for the good efforts of participating in this journal club in the past few months. Let's take a break and resume next year!

Cheers,
Shan

An interesting paper about -ive refractive index

2007-12-06T19:50:00.001+08:00

Lately, we have been discussing about the so called negative refractive index materials (Meta Materials!), an example of which is a super-lens. I found this paper in the Arxiv web site, that negates the whole idea of -ive refraction. Some of you might find it interesting.
Cheers
Shakil

http://arxiv.org/abs/0712.0605v1

"Correct Definition of the Poynting Vector in Electrically and Magnetically Polarizable Medium Reveals that Negative Refraction is Impossible"

Author: V. A. Markel

journal club 29 Nov 2007

2007-12-03T11:42:00.001+08:00

Hi all,

For our journal club this thursday (29/11 10.30am pantry),
let's have a discussion on the attached paper, which is related to the other paper I chose the last time.

Thanks,
Wai Teng

Journal club on 22 Nov 2007

2007-11-20T11:11:00.000+08:00

Hi all,

It is a new cycle of Journal club again – this week I will be presenting on work that I did during Perth attachment.

“Exploring Fourier Holography for Phase Imaging Applications”

Date: 22 Nov
Time: 10.30am
Venue: pantry area

The location is tentative, maybe I can book the little discussion room in division office but not sure now, and will email again if there is an update.

Regards,
Shan

Journal club - Nov 15 2007

2007-11-13T13:18:00.000+08:00

Title: Polarizatio-sensitive full-field optical coherence tomography
Gael Moneron,1 Albert-Claude Boccara,1 and Arnaud Dubois2,*

citation: OPTICS LETTERS / Vol. 32, No. 14 / July 15, 2007
Abstract: We present a polarization-sensitive full-field optical coherence tomography system that can produce highresolution images of the linear retardance and reflectivity properties of biological media. En face images can be delivered at a frame rate of 3.5 Hz by combination of interferometric images acquired by two CCD cameras in an interference microscope illuminated with a tungsten halogen lamp. Isotropic spatial resolution of 1.0 um achieved. The technique is demonstrated on ex vivo muscle tissues.
Date: Nov 15 2007
Venue: Division pantry area

Journal Club - Mapping polymer birefringence in three-dimensions using a polarizing microscope with oblique illumination

2007-11-05T20:20:00.000+08:00

Dear All,

I am going to discuss following interesting paper that talks about measuring 3D distribution of birefringence in the sample. It is interesting in its own right as a basic technique and seems to be a good method of visualizing microtubules during mitosis without any label .

Mapping polymer birefringence in three-dimensions using a polarizing microscope with oblique illumination
Michael Shribak and Rudolf Oldenbourg
Marine Biological Laboratory, Woods Hole, MA 02543, USA

ABSTRACT

We have been developing a polarized light microscope with liquid crystal universal compensator and circular polarizer (the LC-PolScope) for recording images, which are independent of the orientation of birefringent objects. Separate images show the retardance and the slow axis azimuth distributions of the in-plane birefringence of the focused region in the specimen. However the measured (apparent) retardance still depends on the angle between the crystal optic axis and the axis of the illuminating beam of light. If the illuminating beam is close to parallel to the optic axis the measured retardance value decreases dramatically and becomes zero when the two axes are parallel. The description of birefringent objects oriented in 3-dimensional space requires the introduction of two additional parameters: the principal retardance and the inclination angle. Together with the azimuth angle they completely characterize the birefringence properties of a specimen, assuming the specimen has a uniaxial optical indicatrix. We devised a new technique for measuring the three birefringence parameters without moving the specimen. For exploring the out-of-plane birefringence the new instrument which is based on the LC-PolScope technique contains an additional spatial light modulator, implemented here as a liquid crystal mask. The mask is located in the aperture plane of the condenser lens. Partial occlusion of the condenser aperture changes the direction of the central ray of the cone of light converging on the specimen. So we can obtain the retardance and azimuth images using different sets of illumination rays. For experimental verification we used a biological object called an aster. An aster consists of nearly parallel arrays of microtubules, a stiff biopolymer, radiating from a common organizing center called a centrosome. The object is spherically symmetric, and its 3 dimensional distribution of birefringence orientation can be predicted. Experimental results have shown the developed polarizing microscope can successfully be used for imaging and measuring three-dimensional orientation of birefringent objects.

Date: November 07, 2007 (Wednesday)
Time: 10.30 am
Venue: E3A, Level-7 Pantry area.

A molecular ruler based on plasmon coupling of single gold and silver nanoparticles

2007-10-30T17:36:00.000+08:00

Carsten Sönnichsen1, 3, Björn M Reinhard2, 3, Jan Liphardt2 & A Paul Alivisatos1

1 Department of Chemistry, University of California, Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
2 Department of Physics, University of California, Berkeley and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.

Förster Resonance Energy Transfer has served as a molecular ruler that reports conformational changes and intramolecular distances of single biomolecules. However, such rulers suffer from low and fluctuating signal intensities, limited observation time due to photobleaching, and an upper distance limit of approx10 nm. Noble metal nanoparticles have plasmon resonances in the visible range and do not blink or bleach. They have been employed as alternative probes to overcome the limitations of organic fluorophores, and the coupling of plasmons in nearby particles has been exploited to detect particle aggregation by a distinct color change in bulk experiments. Here we demonstrate that plasmon coupling can be used to monitor distances between single pairs of gold and silver nanoparticles. We followed the directed assembly of gold and silver nanoparticle dimers in real time and studied the kinetics of single DNA hybridization events. These 'plasmon rulers' allowed us to continuously monitor separations of up to 70 nm for >3,000 s.

This a more application based work but quite interesting. A very simple application of a complex phenomenon.

Date : 1st Nov '07
Time: 10:30 am - 11:30 am
Venue: E3A, 7th Floor Lounge

Comsol User Conference 2007

2007-10-29T20:08:00.000+08:00

Please find sign-up info for following workshop info of Comsol Physics by clicking above.

The workshop is held on 15 Nov 2007

Microscopy at 29 nm optical resolution

2007-10-22T17:42:00.001+08:00

Dear Bioimaging People
Hello

Here is an interesting paper to discuss that I believe may generate some ideas. It is about Stimulated Emission Depletion (STED) fluorescence microscopy, invented by Stefen Hell's group in Germany, and has apparently removed the barriers of classical diffraction limit in optical resolution. In this paper they are claiming a resolution of 29 nm ( who needs near-field microscopy like NSOM or other scanning probe techniques now!). Anyway, let's talk about it on 25th.

Cheers

Shakil

Citation: "STED microscopy with continuous wave beams", Katrin I. Willig, Benjamin Harke, Rebecca Medda and Stefan W. Hell, Nature Methods 21 October, 2007.
Published online at http://www.nature.com/naturemethods

http://www.nature.com.libproxy1.nus.edu.sg/nmeth/journal/vaop/ncurrent/pdf/nmeth1108.pdf

Journal Club Oct 17 10.30am

2007-10-15T17:30:00.000+08:00

Sub–Diffraction-Limited Optical Imaging with a Silver Superlens
Nicholas Fang, Hyesog Lee, Cheng Sun, Xiang Zhang

Science, Vol. 308, 534-537 (2005)

Recent theory has predicted a superlens that is capable of producing sub–
diffraction-limited images. This superlens would allow the recovery of evanescent
waves in an image via the excitation of surface plasmons. Using silver as a natural
optical superlens, we demonstrated sub–diffraction-limited imaging with 60-
nanometer half-pitch resolution, or one-sixth of the illumination wavelength. By
proper design of the working wavelength and the thickness of silver that allows
access to a broad spectrum of subwavelength features, we also showed that
arbitrary nanostructures can be imaged with good fidelity. The optical superlens
promises exciting avenues to nanoscale optical imaging and ultrasmall optoelectronic
devices.

WITec Workshop at NTU.

2007-10-12T10:24:00.001+08:00

Hi friends,
Sorry i am a bit late in posting this announcement. There is an optics related workshop being held in NTU on 18th Oct. The details are as follows:

Combining Confocal Raman, High Resolution Optical and Scanning Probe Microscopy.

With application in the field of material science, pharmaceutics, life science, semiconductors and nanotechnology.

On the 18^th of October 2007 at NTU School of Material Science and Engineering, Polymer Lab.

Further details is in the flyer attached to this email.

Limited places is available so if you are interested, please register early to avoid disappointment.

Best regards,

Shawn

Extrad Instrumentation

371 Beach Road, #02-32 Keypoint

Singapore 199597

Tel: +65 6296 6908 Fax: +65 6296 6906

Hp: 9026 5667

Journal club schedule

2007-10-11T13:56:00.000+08:00

Journal Club Oct 11 07 10.30am

2007-10-09T15:19:00.000+08:00

Paper Details:

Nat Methods. 2007 Sep;4(9):717-9. Epub 2007 Aug 12.

Tomographic phase microscopy.

Choi W, Fang-Yen C, Badizadegan K, Oh S, Lue N, Dasari RR, Feld MS.

G.R. Harrison Spectroscopy Laboratory, 77 Massachusetts Avenue 6-014, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

We report a technique for quantitative three-dimensional (3D) mapping of refractive index in live cells and tissues using a phase-shifting laser interferometric microscope with variable illumination angle. We demonstrate tomographic imaging of cells and multicellular organisms, and time-dependent changes in cell structure. Our results will permit quantitative characterization of specimen-induced aberrations in high-resolution microscopy and have multiple applications in tissue light scattering.

Discussion leader: Shan
Time: Oct 11 10.30am
Venue: Div pantry area

first to post

2007-10-09T12:11:00.000+08:00

Hi welcome all! Hope this will be an enriching place for all of us.