What is a self intensity test in STD NMR?

Some papers report performing a "STD self intensity" test to check the aggregation of compounds in STD NMR. Can anyone please elaborate how such a test is performed?

07 August 2019 6,832 2 View

What is the correct equation to use when weighing the different chemical shifts of 1H and 15N nuclei in SOFAST HMQC spectra?

I read in the attached paper the equation for HSQC spectra (equation 8). What about HMQC? I cannot find a reference online. Thanks!

04 May 2019 9,770 2 View

After my TEV cleavage site I have a remaining 'am' sequence. Where does this come from?

I am purifying a protein with a his tag. The TEV cleavage site I read is composed of ENLYFQG, and this G remains after cleavage. What I found to also remain is an 'am'. It is before the first...

09 October 2017 1,393 2 View

No title

I have lysed my e. coli cells (after adding protease inhibitors to the lysis buffer) and freezed the lysate. I then unfroze with the intent of purifying my protein , however due to column...

06 July 2017 4,359 7 View

Has anyone tried to add IPTG to auto inducing media like ZYM? Did you notice an increase in protien expression or is it pointless?

I express using BL21 DE3 e-coli cells and use the ZYM 5052 media. Some colleagues who also use this media have suggested adding IPTG to increase the protein expression. Would that make any sense...

06 July 2017 6,309 3 View

Effect of 1000 folds antibiotic addition to e. coli culture media?

I usually add 100ug/ml of kanamycin to my ZYM culture media. I accidently in a moment of fatigue added the entire 100mg/ml stock to one of my batches! What effect will this have on the cell growth...

07 August 2016 4,940 3 View

My DNA plasmid purification yielded a 260/280 ratio of 2.15. Why?

After following the exact protocol of the NucleoSpin Plasmid purification kit, I measured the concentration to find the 260/280 ratio 2.15! Any idea what could have gone wrong and how can I fix this?

04 May 2016 2,767 4 View

Can I re-induce protein expression after storage at 4 degrees Celsius?

I was expressing protein in E coli cells at 37 degrees and the OD was 1. I had to store the culture over 3 nights, so I stored it at 4 degrees to prevent over expression. After the 3 nights I...

04 May 2016 3,099 4 View

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

MGL tools

20 June 2021 0 0 View

i have some problem with chtMultiRegionSimpleFoam

--> FOAM FATAL ERROR: Maximum number of iterations exceeded From function Foam::scalar Foam::species::thermo::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar) const) const [with Thermo = Foam::hConstThermo >; Type = Foam::sensibleEnthalpy; Foam::scalar = double; Foam::species::thermo = Foam::species::thermo >, Foam::sensibleEnthalpy>] in file /home/ubuntu/OpenFOAM/OpenFOAM-4.1/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 66. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::calculate() at ??:? #3 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::correct() at ??:? #4 ? at ??:? #5 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #6 ? at ??:?

24 March 2021 0 0 View

How two melting peaks in DSC of polypropylene can be merged into one crystallization peak?

The figure shows DSC cooling (blue) and 2nd heating (green) curves (step: 10 K/min) for a commercial sample supplied as Atactic Polypropylene (APP). The heating curve illustrates two major...

03 March 2021 5,857 3 View

Resistor definition in Piezoelectric bimorph with ANSYS workbench

Hello, good day! I am trying to simulate similar bimorph piezoelectric harvester with below commands. However, the output power doesn't change with resistor value. Please help to find the reason. ET,10,CIRCU94,0 !SET UP RESISTOR R,1,100000 !RESISTANCE VALUE TYPE,10 !SET ELEMENT TYPE E,1,2 !CREATE RESISTOR BETWEEN NODES 1 AND 2 Thanks in advance Regards,

02 March 2021 0 0 View

Arena simulation - how do i model the following model in ARENA (see description) (new to ARENA)?

Hello, I'm fairly new to ARENA and I have the following problem: I have two queues in which, in each queue, a different order type arrives (both having an arrival rate of exponential 10). Order...

02 March 2021 2,431 3 View

How to repeat an operation on an atom selection for multiple times in PyMol?

Hi, I am trying to construct a multi-layer fibril structure from a single layer in PyMol by translating the layer along the fibril axis. For now, I am able to use the Translate command in PyMol...

02 March 2021 4,569 4 View

Why Austenite grains in steel show much more twinning than ferrite grains?

It is oftentimes said to be a distinctive metallographic trait that differentiates a fully austenitic and a fully felly ferritic steel without etching that might distinguish between two. Why...

02 March 2021 728 2 View

Why might my GFP tag be dissociating from my plasmid after transfection?

I have a set of stably transfected cell lines all transfected with plasmids containing GFP tags on the C terminus. During a western blot using anti-GFP antibody, one of my plasmids has dissociated...

01 March 2021 9,310 4 View