Advanced Electron Microscopy - Science topic

Is this Correct That I can reduce Distrotions to Ideally zero and reduce noise upto a limit but no completly zero? right ,In digital communication

The TEM data that I received is in .EMD (electron microscopy dataset) format, how do I extract/visualize the data, which software should I use?

Hello there!

I would like to prepare sucrose solutions with different densities to purify proteins (sucrose gradients, sucrose cushions, etc). In order to do so, I would like to know the density of a sucrose solution at a given concentration and temperature (assume constant 25 ºC). I have been looking through diverse online resources but have not found anything that clearly correlates sucrose density with its concentration.

Any idea?

Thanks

Does different microscope measure different width(e.g. x, y and z rather than x only) of a particular device having only x width at the same objective?

I will be cryo-fixing a variety of plant species (woody eudicots) for ultrastructure studies via transmission electron microscopy. Previously, I have used standard chemical fixation techniques, which have not provided optimal morphology preservation. Given that cryo-fixation may be better suited for preservation and eliminating artifacts, I am interested in maximizing leaf sucrose content (sucrose serves as a cryo-protectant) in order to minimize crystal formation.

In the past, my lab has left plants in our dark room overnight (16 hours) to allow for starch degradation. My thought is that degradation of starch for chemical fixation is ideal, as starch decreases fixation penetration efficiency and time. In the context of cryo-fixing, I would guess that maximizing starch content is ideal as this will allow for faster freezing.

Any thoughts or suggestions on minimizing artifacts with cryo-fixing plant tissues would be greatly appreciated!

I operate JEOL JSM 7001F. I always found it hard to get good quality images while studying glass substrate (and other non-conductable substrates) samples due to charge accumulation.

Now there's a task for me to get image of 50-70 nm particles on a glass substrate, which seems impossible if i dont use disposition of metal on a surface. Could you please share tips and tricks how you deal with such substrates?

Today I found an interesting paper by G. Poelz (retired from Hamburg University) which suggests that electrons have wave character, see http://arxiv.org/pdf/1206.0620.pdf. Basically he describes an electron model based on the solution of the wave equation in spherical coordinates (see Appendix 6.2 in his paper). This would need the use of spherical Bessel functions of the first kind (see for instance: http://mathworld.wolfram.com/SphericalBesselFunctionoftheFirstKind.html).

Interestingly, I found that George Shpenkov also uses a similar method to describe not only electrons but other atoms as well, based on the solution of the wave equation in spherical coordinates. See his page at this www.researchgate.net or at http://shpenkov.janmax.com. Shpenkov asserts that his method is different from the electron cloud model based on the Schrodinger equation.

While of course this kind of electron model may be different from the standard picture, it seems to be able to fulfill Louis de Broglie's vision in his Nobel lecture: Wave nature of electrons. (see http://www.nobelprize.org/nobel_prizes/physics/laureates/1929/broglie-lecture.pdf)

So do you think it is possible to find an exact electron model based on the solution of the wave equation in spherical coordinates?

Dear colleagues,

I defended my Ph.D. thesis in October 2016 and now I am looking for a postdoctoral position in microscopy (AFM, TEM, SEM) and biophysics of microorganisms (especially, viruses, I like them :)).

My CV is attached. If there is an open position in your lab, please, write me.

Best regards,

Denis  

Dear colleagues,

Preparation of blocks for FIB-SEM tomography is a little tricky process. Which design do you prefer and which technique and tricks use in the preparation?

I make the blocks like this one, do you have better ideas?

Cheers,

Denis

CBED (convergent beam electron diffraction) is known as one of the most sensitive techniques for local lattice parameter determination using electrons. I have no doubts regarding the precision of this technique, but as far as I understand CBED the most important input is the electron energ since from this the electron wavelength and, thus, the lattice parameter will be derived. In other words, to me it seems that the accuracy is more restricted by the believe of the high voltage shown by the TEM, not even mention the local sample heating. If this is right: How accurate is CBED? If somebody is writing 4.466873261 Å...down to which decimal place this number is credible?

Looking through the literature, there are many slightly different techniques for fixing biological specimens using different pre-post fixatives, mainly paraformaldehyde, gluteraldehyde, cacodylate and osmium tetroxide followed by critical point drying but all of the papers use slightly different concentrations with little justification as to why. If anyone has access to a solid protocol for this it would be greatly appreciated.

Hello,

I was looking at a couple of histological slides from a book. I was wondering if anyone knew how to determine whether a slide is from the pituitary gland just from looking at the features of the image and nothing else.

Thank you,

Timon S

Relative dislocation density using the approach of Hirsch et al.

Dislocation Density, ρ = (β²)/(9.b²)

b = Burgers Vector, and

β = Integrated Breadth (computed numerically from XRD profile data)

Let us take the example of SiC 4H (004)s reflection and the use of XRD rocking curve analysis.

How should I figure out b, Burgers Vector?

Models of enzyme complexes not yet developed on the basis of other imaging techniques (e.g.X-ray) may be of interest in studies on enzyme function.

I have been reading about EH for sometime and do not understand why an elliptical illumination is used in this case.

I got two results which are totally different when applying EDX SEM at two different directions perpendicular on each other for an aluminum metal. What 's the interpretation for such result?

I am using UASB reactors for the treatment of landfill leachate in a laboratory scale study. I would like to take the Scanning Electron Microscopy image of the granules developed in the UASB. Can anyone help me how to prepare the sample for the SEM Imaging.

Many thanks in advance

I am trying to TEM image extracellular vesicles. I would like to know if it is possible to use formvar carbon coated grids for extracellular vesicle imaging without glow discharge or any other special treatment to make it more hydrophilic? What are the options for coating except for Poly-L-Lysine?

Thanks

I performed TEM analysis for my bacteriohage.repetitively I got only salts images how to avoid the presence of salts during TEM analysis.

Hello, I would like to start with EAD. Which zoom/Magnification Indication do I need? What is your model of microscope? In the future I would

start with SSR recording, is the microscope for EAD enough for SSR?

Thank you

In slice and view applications of FIB/SEM dual beam systems, which software has a high quality 3D reconstructed volume image? 

Hello,

I am trying to do Scanning Block Face Electron Microscopy of my rat hippocampal slice culture samples. The protocol is supposed to stain membranes (3 x Osmium Tetroxide, then Lead, then Uranium, then dehydration and DURCUPAN resin infiltration) but the cells do not look like cells and the sample seems to be very frangible (the surface is not smooth after you cut it). 

And there are just bubbles everywhere.

Can you help me? Why it happens?

Gosia

What is the method for preparation of diatom cells for SEM imaging?

To get a very precise EBSD analysis, I need to have a perfect adjustments in the SEM to be able to detect small objects in high magnifications. For that a very good Beam/Source alignment is necessary.

I just want to ensure that what I am doing usually is correct (in JSM 7001F):

Source Alignment, PC18, then OL stig.

Beam Alignment, PC8, then OL stig.

I do this for any Acc. Voltage that I use. To do Source and Beam alignment, after Wobbling, I just adjust X,Y knobs until the image does not move.

Is the procedure correct? anybody has other experience? Because I sometimes do not get the sharpness I expect.

I read somewhere that for Source alignment you should not care about image movement and just adjust the X,Y knobs to get the brightest image, and then adjust the movement by Beam alignment.

I am trying to take photos of H&E stained tissue with a monochrome Nikon microscope camera, and I can't seem to choose the right filter to apply to the image. I am using NIS Elements software. I would like to know does anyone have any suggestions if there is a pre-set H&E channel I am missing.